Copy in libbacktrace from gcc

This copies in libbacktrace from the gcc repository as it was in the
commit 62e420293a293608f383d9b9c7f2debd666e9fc9.  GDB is going to
start using this library soon.

A dependency between GDB and libbacktrace has already been added to
the top level Makefile, so, after this commit, when building GDB,
libbacktrace will be built first.  However, libbacktrace is not yet
linked into GDB, or used by GDB in any way.

It is possible to stop libbacktrace being built by configuring the
tree with --disable-libbacktrace.

This commit does NOT update src-release.sh, that will be done in the
next commit, this commit ONLY imports libbacktrace from gcc.  This
means that if you try to make a release of GDB from exactly this
commit then the release tar file will not include libbacktrace.
However, as libbacktrace is an optional dependency this is fine.

libbacktrace/ChangeLog.jit

@@ -0,0 +1,14 @@
+2014-09-24  David Malcolm  <dmalcolm@redhat.com>
+
+	* ChangeLog.jit: Add copyright footer.
+
+2013-10-03  David Malcolm  <dmalcolm@redhat.com>
+
+	* configure.ac: Add --enable-host-shared.
+	* configure: Regenerate.
+
+Copyright (C) 2013-2014 Free Software Foundation, Inc.
+
+Copying and distribution of this file, with or without modification,
+are permitted in any medium without royalty provided the copyright
+notice and this notice are preserved.

libbacktrace/Makefile.am

@@ -0,0 +1,586 @@
+# Makefile.am -- Backtrace Makefile.
+# Copyright (C) 2012-2021 Free Software Foundation, Inc.
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+
+#     (1) Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+
+#     (2) Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+
+#     (3) The name of the author may not be used to
+#     endorse or promote products derived from this software without
+#     specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+ACLOCAL_AMFLAGS = -I .. -I ../config
+
+AM_CPPFLAGS = -I $(top_srcdir)/../include -I $(top_srcdir)/../libgcc \
+	-I ../libgcc
+
+AM_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) $(PIC_FLAG) $(CET_HOST_FLAGS)
+
+noinst_LTLIBRARIES = libbacktrace.la
+
+libbacktrace_la_SOURCES = \
+	backtrace.h \
+	atomic.c \
+	dwarf.c \
+	fileline.c \
+	internal.h \
+	posix.c \
+	print.c \
+	sort.c \
+	state.c
+
+BACKTRACE_FILES = \
+	backtrace.c \
+	simple.c \
+	nounwind.c
+
+FORMAT_FILES = \
+	elf.c \
+	macho.c \
+	pecoff.c \
+	unknown.c \
+	xcoff.c
+
+VIEW_FILES = \
+	read.c \
+	mmapio.c
+
+ALLOC_FILES = \
+	alloc.c \
+	mmap.c
+
+EXTRA_libbacktrace_la_SOURCES = \
+	$(BACKTRACE_FILES) \
+	$(FORMAT_FILES) \
+	$(VIEW_FILES) \
+	$(ALLOC_FILES)
+
+libbacktrace_la_LIBADD = \
+	$(BACKTRACE_FILE) \
+	$(FORMAT_FILE) \
+	$(VIEW_FILE) \
+	$(ALLOC_FILE)
+
+libbacktrace_la_DEPENDENCIES = $(libbacktrace_la_LIBADD)
+
+# Testsuite.
+
+# Add a test to this variable if you want it to be built.
+check_PROGRAMS =
+
+# Add a test to this variable if you want it to be run.
+TESTS =
+
+# Add a test to this variable if you want it to be built and run.
+BUILDTESTS =
+
+# Add a file to this variable if you want it to be built for testing.
+check_DATA =
+
+# Flags to use when compiling test programs.
+libbacktrace_TEST_CFLAGS = $(EXTRA_FLAGS) $(WARN_FLAGS) -g
+
+if USE_DSYMUTIL
+
+%.dSYM: %
+	$(DSYMUTIL) $<
+
+endif USE_DSYMUTIL
+
+if NATIVE
+check_LTLIBRARIES = libbacktrace_alloc.la
+
+libbacktrace_alloc_la_SOURCES = $(libbacktrace_la_SOURCES)
+libbacktrace_alloc_la_LIBADD = $(BACKTRACE_FILE) $(FORMAT_FILE) read.lo alloc.lo
+
+libbacktrace_alloc_la_DEPENDENCIES = $(libbacktrace_alloc_la_LIBADD)
+
+check_LTLIBRARIES += libbacktrace_noformat.la
+
+libbacktrace_noformat_la_SOURCES = $(libbacktrace_la_SOURCES)
+libbacktrace_noformat_la_LIBADD = $(BACKTRACE_FILE) $(VIEW_FILE) $(ALLOC_FILE)
+
+libbacktrace_noformat_la_DEPENDENCIES = $(libbacktrace_noformat_la_LIBADD)
+
+if HAVE_ELF
+if HAVE_OBJCOPY_DEBUGLINK
+
+TEST_BUILD_ID_DIR=$(abs_builddir)/usr/lib/debug/.build-id/
+
+check_LTLIBRARIES += libbacktrace_elf_for_test.la
+
+libbacktrace_elf_for_test_la_SOURCES = $(libbacktrace_la_SOURCES)
+libbacktrace_elf_for_test_la_LIBADD = $(BACKTRACE_FILE) elf_for_test.lo \
+	$(VIEW_FILE) $(ALLOC_FILE)
+
+elf_for_test.c: elf.c
+	SEARCH='^#define SYSTEM_BUILD_ID_DIR.*$$'; \
+	REPLACE="#define SYSTEM_BUILD_ID_DIR \"$(TEST_BUILD_ID_DIR)\""; \
+	$(SED) "s%$$SEARCH%$$REPLACE%" \
+		$< \
+		> $@.tmp
+	mv $@.tmp $@
+
+endif HAVE_OBJCOPY_DEBUGLINK
+endif HAVE_ELF
+
+elf_%.c: elf.c
+	SEARCH='#error "Unknown BACKTRACE_ELF_SIZE"'; \
+	REPLACE='#undef BACKTRACE_ELF_SIZE\
+	#define BACKTRACE_ELF_SIZE'; \
+	$(SED) "s/^$$SEARCH\$$/$$REPLACE $*/" \
+		$< \
+		> $@.tmp
+	mv $@.tmp $@
+
+xcoff_%.c: xcoff.c
+	SEARCH='#error "Unknown BACKTRACE_XCOFF_SIZE"'; \
+	REPLACE='#undef BACKTRACE_XCOFF_SIZE\
+	#define BACKTRACE_XCOFF_SIZE'; \
+	$(SED) "s/^$$SEARCH\$$/$$REPLACE $*/" \
+		$< \
+		> $@.tmp
+	mv $@.tmp $@
+
+test_elf_32_SOURCES = test_format.c testlib.c
+test_elf_32_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+test_elf_32_LDADD = libbacktrace_noformat.la elf_32.lo
+
+BUILDTESTS += test_elf_32
+
+test_elf_64_SOURCES = test_format.c testlib.c
+test_elf_64_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+test_elf_64_LDADD = libbacktrace_noformat.la elf_64.lo
+
+BUILDTESTS += test_elf_64
+
+test_macho_SOURCES = test_format.c testlib.c
+test_macho_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+test_macho_LDADD = libbacktrace_noformat.la macho.lo
+
+BUILDTESTS += test_macho
+
+test_xcoff_32_SOURCES = test_format.c testlib.c
+test_xcoff_32_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+test_xcoff_32_LDADD = libbacktrace_noformat.la xcoff_32.lo
+
+BUILDTESTS += test_xcoff_32
+
+test_xcoff_64_SOURCES = test_format.c testlib.c
+test_xcoff_64_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+test_xcoff_64_LDADD = libbacktrace_noformat.la xcoff_64.lo
+
+BUILDTESTS += test_xcoff_64
+
+test_pecoff_SOURCES = test_format.c testlib.c
+test_pecoff_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+test_pecoff_LDADD = libbacktrace_noformat.la pecoff.lo
+
+BUILDTESTS += test_pecoff
+
+test_unknown_SOURCES = test_format.c testlib.c
+test_unknown_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+test_unknown_LDADD = libbacktrace_noformat.la unknown.lo
+
+BUILDTESTS += test_unknown
+
+unittest_SOURCES = unittest.c testlib.c
+unittest_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+unittest_LDADD = libbacktrace.la
+
+BUILDTESTS += unittest
+
+unittest_alloc_SOURCES = $(unittest_SOURCES)
+unittest_alloc_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+unittest_alloc_LDADD = libbacktrace_alloc.la
+
+BUILDTESTS += unittest_alloc
+
+check_LTLIBRARIES += libbacktrace_instrumented_alloc.la
+
+libbacktrace_instrumented_alloc_la_SOURCES = $(libbacktrace_la_SOURCES)
+libbacktrace_instrumented_alloc_la_LIBADD = $(BACKTRACE_FILE) $(FORMAT_FILE) \
+	read.lo instrumented_alloc.lo
+
+libbacktrace_instrumented_alloc_la_DEPENDENCIES = \
+	$(libbacktrace_instrumented_alloc_la_LIBADD)
+
+instrumented_alloc.lo: alloc.c
+
+allocfail_SOURCES = allocfail.c testlib.c
+allocfail_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+allocfail_LDADD = libbacktrace_instrumented_alloc.la
+
+check_PROGRAMS += allocfail
+
+allocfail.sh: allocfail
+
+TESTS += allocfail.sh
+
+if USE_DSYMUTIL
+check_DATA += allocfail.dSYM
+endif USE_DSYMUTIL
+
+if HAVE_ELF
+if HAVE_OBJCOPY_DEBUGLINK
+
+b2test_SOURCES = $(btest_SOURCES)
+b2test_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+b2test_LDFLAGS = -Wl,--build-id
+b2test_LDADD = libbacktrace_elf_for_test.la
+
+check_PROGRAMS += b2test
+TESTS += b2test_buildid
+
+if HAVE_DWZ
+
+b3test_SOURCES = $(btest_SOURCES)
+b3test_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+b3test_LDFLAGS = -Wl,--build-id
+b3test_LDADD = libbacktrace_elf_for_test.la
+
+check_PROGRAMS += b3test
+TESTS += b3test_dwz_buildid
+
+endif HAVE_DWZ
+
+endif HAVE_OBJCOPY_DEBUGLINK
+endif HAVE_ELF
+
+btest_SOURCES = btest.c testlib.c
+btest_CFLAGS = $(libbacktrace_TEST_CFLAGS) -O
+btest_LDADD = libbacktrace.la
+
+BUILDTESTS += btest
+
+if USE_DSYMUTIL
+check_DATA += btest.dSYM
+endif USE_DSYMUTIL
+
+if HAVE_ELF
+
+btest_lto_SOURCES = btest.c testlib.c
+btest_lto_CFLAGS = $(libbacktrace_TEST_CFLAGS) -O -flto
+btest_lto_LDADD = libbacktrace.la
+
+BUILDTESTS += btest_lto
+
+endif HAVE_ELF
+
+btest_alloc_SOURCES = $(btest_SOURCES)
+btest_alloc_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+btest_alloc_LDADD = libbacktrace_alloc.la
+
+BUILDTESTS += btest_alloc
+
+if USE_DSYMUTIL
+check_DATA += btest_alloc.dSYM
+endif USE_DSYMUTIL
+
+if HAVE_DWZ
+
+%_dwz: %
+	rm -f $@ $@_common.debug
+	cp $< $@_1
+	cp $< $@_2
+	if $(DWZ) -m $@_common.debug $@_1 $@_2; then \
+	  rm -f $@_2; \
+	  mv $@_1 $@; \
+	else \
+	  echo "Ignoring dwz errors, assuming that test passes"; \
+	  cp $< $@; \
+	fi
+
+TESTS += btest_dwz
+
+if HAVE_OBJCOPY_DEBUGLINK
+
+TESTS += btest_dwz_gnudebuglink
+
+endif HAVE_OBJCOPY_DEBUGLINK
+
+endif HAVE_DWZ
+
+stest_SOURCES = stest.c
+stest_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+stest_LDADD = libbacktrace.la
+
+BUILDTESTS += stest
+
+if USE_DSYMUTIL
+check_DATA += stest.dSYM
+endif USE_DSYMUTIL
+
+stest_alloc_SOURCES = $(stest_SOURCES)
+stest_alloc_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+stest_alloc_LDADD = libbacktrace_alloc.la
+
+BUILDTESTS += stest_alloc
+
+if USE_DSYMUTIL
+check_DATA += stest_alloc.dSYM
+endif USE_DSYMUTIL
+
+if HAVE_ELF
+
+ztest_SOURCES = ztest.c testlib.c
+ztest_CFLAGS = $(libbacktrace_TEST_CFLAGS) -DSRCDIR=\"$(srcdir)\"
+ztest_LDADD = libbacktrace.la
+ztest_alloc_LDADD = libbacktrace_alloc.la
+
+if HAVE_ZLIB
+ztest_LDADD += -lz
+ztest_alloc_LDADD += -lz
+endif
+ztest_LDADD += $(CLOCK_GETTIME_LINK)
+ztest_alloc_LDADD += $(CLOCK_GETTIME_LINK)
+
+BUILDTESTS += ztest
+
+ztest_alloc_SOURCES = $(ztest_SOURCES)
+ztest_alloc_CFLAGS = $(ztest_CFLAGS)
+
+BUILDTESTS += ztest_alloc
+
+endif HAVE_ELF
+
+edtest_SOURCES = edtest.c edtest2_build.c testlib.c
+edtest_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+edtest_LDADD = libbacktrace.la
+
+BUILDTESTS += edtest
+
+if USE_DSYMUTIL
+check_DATA += edtest.dSYM
+endif USE_DSYMUTIL
+
+edtest_alloc_SOURCES = $(edtest_SOURCES)
+edtest_alloc_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+edtest_alloc_LDADD = libbacktrace_alloc.la
+
+if USE_DSYMUTIL
+check_DATA += edtest_alloc.dSYM
+endif USE_DSYMUTIL
+
+BUILDTESTS += edtest_alloc
+
+edtest2_build.c: gen_edtest2_build; @true
+gen_edtest2_build: $(srcdir)/edtest2.c
+	cat $(srcdir)/edtest2.c > tmp-edtest2_build.c
+	$(SHELL) $(srcdir)/../move-if-change tmp-edtest2_build.c edtest2_build.c
+	echo timestamp > $@
+
+if HAVE_PTHREAD
+
+BUILDTESTS += ttest
+
+ttest_SOURCES = ttest.c testlib.c
+ttest_CFLAGS = $(libbacktrace_TEST_CFLAGS) -pthread
+ttest_LDADD = libbacktrace.la
+
+if USE_DSYMUTIL
+check_DATA += ttest.dSYM
+endif USE_DSYMUTIL
+
+BUILDTESTS += ttest_alloc
+
+ttest_alloc_SOURCES = $(ttest_SOURCES)
+ttest_alloc_CFLAGS = $(ttest_CFLAGS)
+ttest_alloc_LDADD = libbacktrace_alloc.la
+
+if USE_DSYMUTIL
+check_DATA += ttest_alloc.dSYM
+endif USE_DSYMUTIL
+
+endif HAVE_PTHREAD
+
+if HAVE_OBJCOPY_DEBUGLINK
+
+TESTS += btest_gnudebuglink
+
+%_gnudebuglink: %
+	$(OBJCOPY) --only-keep-debug $< $@.debug
+	$(OBJCOPY) --strip-debug --add-gnu-debuglink=$@.debug $< $@
+
+endif HAVE_OBJCOPY_DEBUGLINK
+
+%_buildid: %
+	./install-debuginfo-for-buildid.sh \
+	  "$(TEST_BUILD_ID_DIR)" \
+	  $<
+	$(OBJCOPY) --strip-debug $< $@
+
+if HAVE_COMPRESSED_DEBUG
+
+ctestg_SOURCES = btest.c testlib.c
+ctestg_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+ctestg_LDFLAGS = -Wl,--compress-debug-sections=zlib-gnu
+ctestg_LDADD = libbacktrace.la
+
+ctesta_SOURCES = btest.c testlib.c
+ctesta_CFLAGS = $(libbacktrace_TEST_CFLAGS)
+ctesta_LDFLAGS = -Wl,--compress-debug-sections=zlib-gabi
+ctesta_LDADD = libbacktrace.la
+
+BUILDTESTS += ctestg ctesta
+
+ctestg_alloc_SOURCES = $(ctestg_SOURCES)
+ctestg_alloc_CFLAGS = $(ctestg_CFLAGS)
+ctestg_alloc_LDFLAGS = $(ctestg_LDFLAGS)
+ctestg_alloc_LDADD = libbacktrace_alloc.la
+
+ctesta_alloc_SOURCES = $(ctesta_SOURCES)
+ctesta_alloc_CFLAGS = $(ctesta_CFLAGS)
+ctesta_alloc_LDFLAGS = $(ctesta_LDFLAGS)
+ctesta_alloc_LDADD = libbacktrace_alloc.la
+
+BUILDTESTS += ctestg_alloc ctesta_alloc
+
+endif
+
+if HAVE_DWARF5
+
+dwarf5_SOURCES = btest.c testlib.c
+dwarf5_CFLAGS = $(libbacktrace_TEST_CFLAGS) -gdwarf-5
+dwarf5_LDADD = libbacktrace.la
+
+BUILDTESTS += dwarf5
+
+if USE_DSYMUTIL
+check_DATA += dwarf5.dSYM
+endif USE_DSYMUTIL
+
+dwarf5_alloc_SOURCES = $(dwarf5_SOURCES)
+dwarf5_alloc_CFLAGS = $(dwarf5_CFLAGS)
+dwarf5_alloc_LDADD = libbacktrace_alloc.la
+
+BUILDTESTS += dwarf5_alloc
+
+if USE_DSYMUTIL
+check_DATA += dwarf5_alloc.dSYM
+endif USE_DSYMUTIL
+
+endif
+
+mtest_SOURCES = mtest.c testlib.c
+mtest_CFLAGS = $(libbacktrace_TEST_CFLAGS) -O
+mtest_LDADD = libbacktrace.la
+
+BUILDTESTS += mtest
+
+if USE_DSYMUTIL
+check_DATA += mtest.dSYM
+endif USE_DSYMUTIL
+
+if HAVE_MINIDEBUG
+
+TESTS += mtest_minidebug
+
+%_minidebug: %
+	$(NM) -D $< -P --defined-only | $(AWK) '{ print $$1 }' | sort > $<.dsyms
+	$(NM) $< -P --defined-only | $(AWK) '{ if ($$2 == "T" || $$2 == "t" || $$2 == "D") print $$1 }' | sort > $<.fsyms
+	$(COMM) -13 $<.dsyms $<.fsyms > $<.keepsyms
+	$(OBJCOPY) --only-keep-debug $< $<.dbg
+	$(OBJCOPY) -S --remove-section .gdb_index --remove-section .comment --keep-symbols=$<.keepsyms $<.dbg $<.mdbg
+	$(OBJCOPY) --strip-all --remove-section ..comment $< $<.strip
+	rm -f $<.mdbg.xz
+	$(XZ) $<.mdbg
+	$(OBJCOPY) --add-section .gnu_debugdata=$<.mdbg.xz $<.strip
+	mv $<.strip $@
+
+endif HAVE_MINIDEBUG
+
+endif NATIVE
+
+if HAVE_ELF
+
+xztest_SOURCES = xztest.c testlib.c
+xztest_CFLAGS = $(libbacktrace_TEST_CFLAGS) -DSRCDIR=\"$(srcdir)\"
+xztest_LDADD = libbacktrace.la
+
+xztest_alloc_SOURCES = $(xztest_SOURCES)
+xztest_alloc_CFLAGS = $(xztest_CFLAGS)
+xztest_alloc_LDADD = libbacktrace_alloc.la
+
+if HAVE_LIBLZMA
+xztest_LDADD += -llzma
+xztest_alloc_LDADD += -llzma
+endif
+
+xztest_LDADD += $(CLOCK_GETTIME_LINK)
+xztest_alloc_LDADD += $(CLOCK_GETTIME_LINK)
+
+BUILDTESTS += xztest xztest_alloc
+
+endif HAVE_ELF
+
+check_PROGRAMS += $(BUILDTESTS)
+
+TESTS += $(BUILDTESTS)
+
+CLEANFILES = \
+	$(TESTS) *.debug elf_for_test.c edtest2_build.c gen_edtest2_build \
+	*.dsyms *.fsyms *.keepsyms *.dbg *.mdbg *.mdbg.xz *.strip
+
+clean-local:
+	-rm -rf usr
+
+# We can't use automake's automatic dependency tracking, because it
+# breaks when using bootstrap-lean.  Automatic dependency tracking
+# with GCC bootstrap will cause some of the objects to depend on
+# header files in prev-gcc/include, e.g., stddef.h and stdarg.h.  When
+# using bootstrap-lean, prev-gcc is removed after each stage.  When
+# running "make install", those header files will be gone, causing the
+# library to be rebuilt at install time.  That may not succeed.
+
+# These manual dependencies do not include dependencies on unwind.h,
+# even though that is part of GCC, because where to find it depends on
+# whether we are being built as a host library or a target library.
+
+INCDIR = $(top_srcdir)/../include
+alloc.lo: config.h backtrace.h internal.h
+backtrace.lo: config.h backtrace.h internal.h
+btest.lo: $(INCDIR)/filenames.h backtrace.h backtrace-supported.h
+dwarf.lo: config.h $(INCDIR)/dwarf2.h $(INCDIR)/dwarf2.def \
+	$(INCDIR)/filenames.h backtrace.h internal.h
+elf.lo: config.h backtrace.h internal.h
+fileline.lo: config.h backtrace.h internal.h
+macho.lo: config.h backtrace.h internal.h
+mmap.lo: config.h backtrace.h internal.h
+mmapio.lo: config.h backtrace.h internal.h
+mtest.lo: backtrace.h backtrace-supported.h
+nounwind.lo: config.h internal.h
+pecoff.lo: config.h backtrace.h internal.h
+posix.lo: config.h backtrace.h internal.h
+print.lo: config.h backtrace.h internal.h
+read.lo: config.h backtrace.h internal.h
+simple.lo: config.h backtrace.h internal.h
+sort.lo: config.h backtrace.h internal.h
+stest.lo: config.h backtrace.h internal.h
+state.lo: config.h backtrace.h backtrace-supported.h internal.h
+unknown.lo: config.h backtrace.h internal.h
+xcoff.lo: config.h backtrace.h internal.h
+xztest.lo: config.h backtrace.h backtrace-supported.h internal.h testlib.h
+ztest.lo: config.h backtrace.h backtrace-supported.h internal.h testlib.h
+
+include $(top_srcdir)/../multilib.am

libbacktrace/README

@@ -0,0 +1,23 @@
+The libbacktrace library
+Initially written by Ian Lance Taylor <iant@google.com>
+
+The libbacktrace library may be linked into a program or library and
+used to produce symbolic backtraces.  Sample uses would be to print a
+detailed backtrace when an error occurs or to gather detailed
+profiling information.
+
+The libbacktrace library is provided under a BSD license.  See the
+source files for the exact license text.
+
+The public functions are declared and documented in the header file
+backtrace.h, which should be #include'd by a user of the library.
+
+Building libbacktrace will generate a file backtrace-supported.h,
+which a user of the library may use to determine whether backtraces
+will work.  See the source file backtrace-supported.h.in for the
+macros that it defines.
+
+As of September 2012, libbacktrace only supports ELF executables with
+DWARF debugging information.  The library is written to make it
+straightforward to add support for other object file and debugging
+formats.

libbacktrace/aclocal.m4

@@ -0,0 +1,867 @@
+# generated automatically by aclocal 1.15.1 -*- Autoconf -*-
+
+# Copyright (C) 1996-2017 Free Software Foundation, Inc.
+
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
+# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+# PARTICULAR PURPOSE.
+
+m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
+m4_ifndef([AC_AUTOCONF_VERSION],
+  [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
+m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.69],,
+[m4_warning([this file was generated for autoconf 2.69.
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+To do so, use the procedure documented by the package, typically 'autoreconf'.])])
+
+# Copyright (C) 2002-2017 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# AM_AUTOMAKE_VERSION(VERSION)
+# ----------------------------
+# Automake X.Y traces this macro to ensure aclocal.m4 has been
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+AC_DEFUN([AM_AUTOMAKE_VERSION],
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+# _AM_AUTOCONF_VERSION(VERSION)
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+m4_define([_AM_AUTOCONF_VERSION], [])
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+# AM_SET_CURRENT_AUTOMAKE_VERSION
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+
+# AM_AUX_DIR_EXPAND                                         -*- Autoconf -*-
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+# Copyright (C) 2001-2017 Free Software Foundation, Inc.
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+# with or without modifications, as long as this notice is preserved.
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+# For projects using AC_CONFIG_AUX_DIR([foo]), Autoconf sets
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+
+# AM_CONDITIONAL                                            -*- Autoconf -*-
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+# Copyright (C) 1997-2017 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
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+# AM_CONDITIONAL(NAME, SHELL-CONDITION)
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+fi])])
+
+# Do all the work for Automake.                             -*- Autoconf -*-
+
+# Copyright (C) 1996-2017 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
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+# This macro actually does too much.  Some checks are only needed if
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+# AM_INIT_AUTOMAKE(PACKAGE, VERSION, [NO-DEFINE])
+# AM_INIT_AUTOMAKE([OPTIONS])
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+You can download and install GNU coreutils to get an 'rm' implementation
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+If you want to complete the configuration process using your problematic
+'rm' anyway, export the environment variable ACCEPT_INFERIOR_RM_PROGRAM
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+    AC_MSG_ERROR([Your 'rm' program is bad, sorry.])
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+# Copyright (C) 2001-2017 Free Software Foundation, Inc.
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+# Add --enable-maintainer-mode option to configure.         -*- Autoconf -*-
+# From Jim Meyering
+
+# Copyright (C) 1996-2017 Free Software Foundation, Inc.
+#
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+# gives unlimited permission to copy and/or distribute it,
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+# AM_MAINTAINER_MODE([DEFAULT-MODE])
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+# Copyright (C) 1997-2017 Free Software Foundation, Inc.
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+# Helper functions for option handling.                     -*- Autoconf -*-
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+# Copyright (C) 2001-2017 Free Software Foundation, Inc.
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+# Copyright (C) 1999-2017 Free Software Foundation, Inc.
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+am_lf='
+'
+case `pwd` in
+  *[[\\\"\#\$\&\'\`$am_lf]]*)
+    AC_MSG_ERROR([unsafe absolute working directory name]);;
+esac
+case $srcdir in
+  *[[\\\"\#\$\&\'\`$am_lf\ \	]]*)
+    AC_MSG_ERROR([unsafe srcdir value: '$srcdir']);;
+esac
+
+# Do 'set' in a subshell so we don't clobber the current shell's
+# arguments.  Must try -L first in case configure is actually a
+# symlink; some systems play weird games with the mod time of symlinks
+# (eg FreeBSD returns the mod time of the symlink's containing
+# directory).
+if (
+   am_has_slept=no
+   for am_try in 1 2; do
+     echo "timestamp, slept: $am_has_slept" > conftest.file
+     set X `ls -Lt "$srcdir/configure" conftest.file 2> /dev/null`
+     if test "$[*]" = "X"; then
+	# -L didn't work.
+	set X `ls -t "$srcdir/configure" conftest.file`
+     fi
+     if test "$[*]" != "X $srcdir/configure conftest.file" \
+	&& test "$[*]" != "X conftest.file $srcdir/configure"; then
+
+	# If neither matched, then we have a broken ls.  This can happen
+	# if, for instance, CONFIG_SHELL is bash and it inherits a
+	# broken ls alias from the environment.  This has actually
+	# happened.  Such a system could not be considered "sane".
+	AC_MSG_ERROR([ls -t appears to fail.  Make sure there is not a broken
+  alias in your environment])
+     fi
+     if test "$[2]" = conftest.file || test $am_try -eq 2; then
+       break
+     fi
+     # Just in case.
+     sleep 1
+     am_has_slept=yes
+   done
+   test "$[2]" = conftest.file
+   )
+then
+   # Ok.
+   :
+else
+   AC_MSG_ERROR([newly created file is older than distributed files!
+Check your system clock])
+fi
+AC_MSG_RESULT([yes])
+# If we didn't sleep, we still need to ensure time stamps of config.status and
+# generated files are strictly newer.
+am_sleep_pid=
+if grep 'slept: no' conftest.file >/dev/null 2>&1; then
+  ( sleep 1 ) &
+  am_sleep_pid=$!
+fi
+AC_CONFIG_COMMANDS_PRE(
+  [AC_MSG_CHECKING([that generated files are newer than configure])
+   if test -n "$am_sleep_pid"; then
+     # Hide warnings about reused PIDs.
+     wait $am_sleep_pid 2>/dev/null
+   fi
+   AC_MSG_RESULT([done])])
+rm -f conftest.file
+])
+
+# Copyright (C) 2009-2017 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# AM_SILENT_RULES([DEFAULT])
+# --------------------------
+# Enable less verbose build rules; with the default set to DEFAULT
+# ("yes" being less verbose, "no" or empty being verbose).
+AC_DEFUN([AM_SILENT_RULES],
+[AC_ARG_ENABLE([silent-rules], [dnl
+AS_HELP_STRING(
+  [--enable-silent-rules],
+  [less verbose build output (undo: "make V=1")])
+AS_HELP_STRING(
+  [--disable-silent-rules],
+  [verbose build output (undo: "make V=0")])dnl
+])
+case $enable_silent_rules in @%:@ (((
+  yes) AM_DEFAULT_VERBOSITY=0;;
+   no) AM_DEFAULT_VERBOSITY=1;;
+    *) AM_DEFAULT_VERBOSITY=m4_if([$1], [yes], [0], [1]);;
+esac
+dnl
+dnl A few 'make' implementations (e.g., NonStop OS and NextStep)
+dnl do not support nested variable expansions.
+dnl See automake bug#9928 and bug#10237.
+am_make=${MAKE-make}
+AC_CACHE_CHECK([whether $am_make supports nested variables],
+   [am_cv_make_support_nested_variables],
+   [if AS_ECHO([['TRUE=$(BAR$(V))
+BAR0=false
+BAR1=true
+V=1
+am__doit:
+	@$(TRUE)
+.PHONY: am__doit']]) | $am_make -f - >/dev/null 2>&1; then
+  am_cv_make_support_nested_variables=yes
+else
+  am_cv_make_support_nested_variables=no
+fi])
+if test $am_cv_make_support_nested_variables = yes; then
+  dnl Using '$V' instead of '$(V)' breaks IRIX make.
+  AM_V='$(V)'
+  AM_DEFAULT_V='$(AM_DEFAULT_VERBOSITY)'
+else
+  AM_V=$AM_DEFAULT_VERBOSITY
+  AM_DEFAULT_V=$AM_DEFAULT_VERBOSITY
+fi
+AC_SUBST([AM_V])dnl
+AM_SUBST_NOTMAKE([AM_V])dnl
+AC_SUBST([AM_DEFAULT_V])dnl
+AM_SUBST_NOTMAKE([AM_DEFAULT_V])dnl
+AC_SUBST([AM_DEFAULT_VERBOSITY])dnl
+AM_BACKSLASH='\'
+AC_SUBST([AM_BACKSLASH])dnl
+_AM_SUBST_NOTMAKE([AM_BACKSLASH])dnl
+])
+
+# Copyright (C) 2001-2017 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# AM_PROG_INSTALL_STRIP
+# ---------------------
+# One issue with vendor 'install' (even GNU) is that you can't
+# specify the program used to strip binaries.  This is especially
+# annoying in cross-compiling environments, where the build's strip
+# is unlikely to handle the host's binaries.
+# Fortunately install-sh will honor a STRIPPROG variable, so we
+# always use install-sh in "make install-strip", and initialize
+# STRIPPROG with the value of the STRIP variable (set by the user).
+AC_DEFUN([AM_PROG_INSTALL_STRIP],
+[AC_REQUIRE([AM_PROG_INSTALL_SH])dnl
+# Installed binaries are usually stripped using 'strip' when the user
+# run "make install-strip".  However 'strip' might not be the right
+# tool to use in cross-compilation environments, therefore Automake
+# will honor the 'STRIP' environment variable to overrule this program.
+dnl Don't test for $cross_compiling = yes, because it might be 'maybe'.
+if test "$cross_compiling" != no; then
+  AC_CHECK_TOOL([STRIP], [strip], :)
+fi
+INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
+AC_SUBST([INSTALL_STRIP_PROGRAM])])
+
+# Copyright (C) 2006-2017 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# _AM_SUBST_NOTMAKE(VARIABLE)
+# ---------------------------
+# Prevent Automake from outputting VARIABLE = @VARIABLE@ in Makefile.in.
+# This macro is traced by Automake.
+AC_DEFUN([_AM_SUBST_NOTMAKE])
+
+# AM_SUBST_NOTMAKE(VARIABLE)
+# --------------------------
+# Public sister of _AM_SUBST_NOTMAKE.
+AC_DEFUN([AM_SUBST_NOTMAKE], [_AM_SUBST_NOTMAKE($@)])
+
+# Check how to create a tarball.                            -*- Autoconf -*-
+
+# Copyright (C) 2004-2017 Free Software Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# _AM_PROG_TAR(FORMAT)
+# --------------------
+# Check how to create a tarball in format FORMAT.
+# FORMAT should be one of 'v7', 'ustar', or 'pax'.
+#
+# Substitute a variable $(am__tar) that is a command
+# writing to stdout a FORMAT-tarball containing the directory
+# $tardir.
+#     tardir=directory && $(am__tar) > result.tar
+#
+# Substitute a variable $(am__untar) that extract such
+# a tarball read from stdin.
+#     $(am__untar) < result.tar
+#
+AC_DEFUN([_AM_PROG_TAR],
+[# Always define AMTAR for backward compatibility.  Yes, it's still used
+# in the wild :-(  We should find a proper way to deprecate it ...
+AC_SUBST([AMTAR], ['$${TAR-tar}'])
+
+# We'll loop over all known methods to create a tar archive until one works.
+_am_tools='gnutar m4_if([$1], [ustar], [plaintar]) pax cpio none'
+
+m4_if([$1], [v7],
+  [am__tar='$${TAR-tar} chof - "$$tardir"' am__untar='$${TAR-tar} xf -'],
+
+  [m4_case([$1],
+    [ustar],
+     [# The POSIX 1988 'ustar' format is defined with fixed-size fields.
+      # There is notably a 21 bits limit for the UID and the GID.  In fact,
+      # the 'pax' utility can hang on bigger UID/GID (see automake bug#8343
+      # and bug#13588).
+      am_max_uid=2097151 # 2^21 - 1
+      am_max_gid=$am_max_uid
+      # The $UID and $GID variables are not portable, so we need to resort
+      # to the POSIX-mandated id(1) utility.  Errors in the 'id' calls
+      # below are definitely unexpected, so allow the users to see them
+      # (that is, avoid stderr redirection).
+      am_uid=`id -u || echo unknown`
+      am_gid=`id -g || echo unknown`
+      AC_MSG_CHECKING([whether UID '$am_uid' is supported by ustar format])
+      if test $am_uid -le $am_max_uid; then
+         AC_MSG_RESULT([yes])
+      else
+         AC_MSG_RESULT([no])
+         _am_tools=none
+      fi
+      AC_MSG_CHECKING([whether GID '$am_gid' is supported by ustar format])
+      if test $am_gid -le $am_max_gid; then
+         AC_MSG_RESULT([yes])
+      else
+        AC_MSG_RESULT([no])
+        _am_tools=none
+      fi],
+
+  [pax],
+    [],
+
+  [m4_fatal([Unknown tar format])])
+
+  AC_MSG_CHECKING([how to create a $1 tar archive])
+
+  # Go ahead even if we have the value already cached.  We do so because we
+  # need to set the values for the 'am__tar' and 'am__untar' variables.
+  _am_tools=${am_cv_prog_tar_$1-$_am_tools}
+
+  for _am_tool in $_am_tools; do
+    case $_am_tool in
+    gnutar)
+      for _am_tar in tar gnutar gtar; do
+        AM_RUN_LOG([$_am_tar --version]) && break
+      done
+      am__tar="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) -chf - "'"$$tardir"'
+      am__tar_="$_am_tar --format=m4_if([$1], [pax], [posix], [$1]) -chf - "'"$tardir"'
+      am__untar="$_am_tar -xf -"
+      ;;
+    plaintar)
+      # Must skip GNU tar: if it does not support --format= it doesn't create
+      # ustar tarball either.
+      (tar --version) >/dev/null 2>&1 && continue
+      am__tar='tar chf - "$$tardir"'
+      am__tar_='tar chf - "$tardir"'
+      am__untar='tar xf -'
+      ;;
+    pax)
+      am__tar='pax -L -x $1 -w "$$tardir"'
+      am__tar_='pax -L -x $1 -w "$tardir"'
+      am__untar='pax -r'
+      ;;
+    cpio)
+      am__tar='find "$$tardir" -print | cpio -o -H $1 -L'
+      am__tar_='find "$tardir" -print | cpio -o -H $1 -L'
+      am__untar='cpio -i -H $1 -d'
+      ;;
+    none)
+      am__tar=false
+      am__tar_=false
+      am__untar=false
+      ;;
+    esac
+
+    # If the value was cached, stop now.  We just wanted to have am__tar
+    # and am__untar set.
+    test -n "${am_cv_prog_tar_$1}" && break
+
+    # tar/untar a dummy directory, and stop if the command works.
+    rm -rf conftest.dir
+    mkdir conftest.dir
+    echo GrepMe > conftest.dir/file
+    AM_RUN_LOG([tardir=conftest.dir && eval $am__tar_ >conftest.tar])
+    rm -rf conftest.dir
+    if test -s conftest.tar; then
+      AM_RUN_LOG([$am__untar <conftest.tar])
+      AM_RUN_LOG([cat conftest.dir/file])
+      grep GrepMe conftest.dir/file >/dev/null 2>&1 && break
+    fi
+  done
+  rm -rf conftest.dir
+
+  AC_CACHE_VAL([am_cv_prog_tar_$1], [am_cv_prog_tar_$1=$_am_tool])
+  AC_MSG_RESULT([$am_cv_prog_tar_$1])])
+
+AC_SUBST([am__tar])
+AC_SUBST([am__untar])
+]) # _AM_PROG_TAR
+
+m4_include([../config/cet.m4])
+m4_include([../config/enable.m4])
+m4_include([../config/lead-dot.m4])
+m4_include([../config/multi.m4])
+m4_include([../config/override.m4])
+m4_include([../config/stdint.m4])
+m4_include([../config/unwind_ipinfo.m4])
+m4_include([../config/warnings.m4])
+m4_include([../libtool.m4])
+m4_include([../ltoptions.m4])
+m4_include([../ltsugar.m4])
+m4_include([../ltversion.m4])
+m4_include([../lt~obsolete.m4])

libbacktrace/alloc.c

@@ -0,0 +1,167 @@
+/* alloc.c -- Memory allocation without mmap.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+/* Allocation routines to use on systems that do not support anonymous
+   mmap.  This implementation just uses malloc, which means that the
+   backtrace functions may not be safely invoked from a signal
+   handler.  */
+
+/* Allocate memory like malloc.  If ERROR_CALLBACK is NULL, don't
+   report an error.  */
+
+void *
+backtrace_alloc (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		 size_t size, backtrace_error_callback error_callback,
+		 void *data)
+{
+  void *ret;
+
+  ret = malloc (size);
+  if (ret == NULL)
+    {
+      if (error_callback)
+	error_callback (data, "malloc", errno);
+    }
+  return ret;
+}
+
+/* Free memory.  */
+
+void
+backtrace_free (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		void *p, size_t size ATTRIBUTE_UNUSED,
+		backtrace_error_callback error_callback ATTRIBUTE_UNUSED,
+		void *data ATTRIBUTE_UNUSED)
+{
+  free (p);
+}
+
+/* Grow VEC by SIZE bytes.  */
+
+void *
+backtrace_vector_grow (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		       size_t size, backtrace_error_callback error_callback,
+		       void *data, struct backtrace_vector *vec)
+{
+  void *ret;
+
+  if (size > vec->alc)
+    {
+      size_t alc;
+      void *base;
+
+      if (vec->size == 0)
+	alc = 32 * size;
+      else if (vec->size >= 4096)
+	alc = vec->size + 4096;
+      else
+	alc = 2 * vec->size;
+
+      if (alc < vec->size + size)
+	alc = vec->size + size;
+
+      base = realloc (vec->base, alc);
+      if (base == NULL)
+	{
+	  error_callback (data, "realloc", errno);
+	  return NULL;
+	}
+
+      vec->base = base;
+      vec->alc = alc - vec->size;
+    }
+
+  ret = (char *) vec->base + vec->size;
+  vec->size += size;
+  vec->alc -= size;
+  return ret;
+}
+
+/* Finish the current allocation on VEC.  */
+
+void *
+backtrace_vector_finish (struct backtrace_state *state,
+			 struct backtrace_vector *vec,
+			 backtrace_error_callback error_callback,
+			 void *data)
+{
+  void *ret;
+
+  /* With this allocator we call realloc in backtrace_vector_grow,
+     which means we can't easily reuse the memory here.  So just
+     release it.  */
+  if (!backtrace_vector_release (state, vec, error_callback, data))
+    return NULL;
+  ret = vec->base;
+  vec->base = NULL;
+  vec->size = 0;
+  vec->alc = 0;
+  return ret;
+}
+
+/* Release any extra space allocated for VEC.  */
+
+int
+backtrace_vector_release (struct backtrace_state *state ATTRIBUTE_UNUSED,
+			  struct backtrace_vector *vec,
+			  backtrace_error_callback error_callback,
+			  void *data)
+{
+  vec->alc = 0;
+
+  if (vec->size == 0)
+    {
+      /* As of C17, realloc with size 0 is marked as an obsolescent feature, use
+	 free instead.  */
+      free (vec->base);
+      vec->base = NULL;
+      return 1;
+    }
+
+  vec->base = realloc (vec->base, vec->size);
+  if (vec->base == NULL)
+    {
+      error_callback (data, "realloc", errno);
+      return 0;
+    }
+
+  return 1;
+}

libbacktrace/allocfail.c

@@ -0,0 +1,136 @@
+/* allocfail.c -- Test for libbacktrace library
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "filenames.h"
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "testlib.h"
+
+extern uint64_t get_nr_allocs (void);
+extern void set_fail_at_alloc (uint64_t);
+extern int at_fail_alloc_p (void);
+
+static int test1 (void) __attribute__ ((noinline, unused));
+static int f2 (int) __attribute__ ((noinline));
+static int f3 (int, int) __attribute__ ((noinline));
+
+static unsigned callback_errors = 0;
+
+static void
+error_callback_full (void *vdata ATTRIBUTE_UNUSED,
+		     const char *msg ATTRIBUTE_UNUSED,
+		     int errnum ATTRIBUTE_UNUSED)
+{
+  if (at_fail_alloc_p ())
+    {
+      set_fail_at_alloc (0);
+      return;
+    }
+
+  callback_errors++;
+}
+
+static int
+callback_full (void *vdata ATTRIBUTE_UNUSED, uintptr_t pc ATTRIBUTE_UNUSED,
+	      const char *filename ATTRIBUTE_UNUSED,
+	      int lineno ATTRIBUTE_UNUSED,
+	      const char *function ATTRIBUTE_UNUSED)
+{
+
+  return 0;
+}
+
+static int
+test1 (void)
+{
+  return f2 (__LINE__) + 1;
+}
+
+static int
+f2 (int f1line)
+{
+  return f3 (f1line, __LINE__) + 2;
+}
+
+static int
+f3 (int f1line ATTRIBUTE_UNUSED, int f2line ATTRIBUTE_UNUSED)
+{
+  int i;
+
+  i = backtrace_full (state, 0, callback_full, error_callback_full, NULL);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test1: unexpected return value %d\n", i);
+      ++failures;
+    }
+
+  if (callback_errors)
+      ++failures;
+
+  return failures;
+}
+
+/* Run all the tests.  */
+
+int
+main (int argc, char **argv)
+{
+  uint64_t fail_at = 0;
+
+  if (argc == 2)
+    {
+      fail_at = atoi (argv[1]);
+      set_fail_at_alloc (fail_at);
+    }
+
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_full, NULL);
+  if (state == NULL)
+    exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+
+#if BACKTRACE_SUPPORTED
+  test1 ();
+#endif
+
+  if (argc == 1)
+    fprintf (stderr, "%llu\n", (long long unsigned) get_nr_allocs ());
+
+  exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/allocfail.sh

@@ -0,0 +1,104 @@
+#!/bin/sh
+
+# allocfail.sh -- Test for libbacktrace library.
+# Copyright (C) 2018-2021 Free Software Foundation, Inc.
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+
+#     (1) Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+
+#     (2) Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+
+#     (3) The name of the author may not be used to
+#     endorse or promote products derived from this software without
+#     specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+set -e
+
+if [ ! -f ./allocfail ]; then
+    # Hard failure.
+    exit 99
+fi
+
+allocs=$(./allocfail 2>&1)
+if [ "$allocs" = "" ]; then
+    # Hard failure.
+    exit 99
+fi
+
+# This generates the following output:
+# ...
+# $ allocfail.sh
+# allocs: 80495
+# Status changed to 0 at 1
+# Status changed to 1 at 3
+# Status changed to 0 at 11
+# Status changed to 1 at 12
+# Status changed to 0 at 845
+# ...
+#
+# We have status 0 for an allocation failure at:
+# - 1 because backtrace_create_state handles failure robustly
+# - 2 because the fail switches backtrace_full to !can_alloc mode.
+# - 11 because failure of elf_open_debugfile_by_buildid does not generate an
+#   error callback beyond the one for the allocation failure itself.
+
+echo "allocs: $allocs"
+
+step=1
+i=1
+passes=0
+prev_status=-1
+while [ $i -le $allocs ]; do
+    if ./allocfail $i >/dev/null 2>&1; status=$?; then
+	true
+    fi
+    if [ $status -gt 1 ]; then
+	echo "Unallowed fail found: $i"
+	# Failure.
+	exit 1
+    fi
+
+    # The test-case would run too long if we would excercise all allocs.
+    # So, run with step 1 initially, and increase the step once we have 10
+    # subsequent passes, and drop back to step 1 once we encounter another
+    # failure.  This takes ~2.6 seconds on an i7-6600U CPU @ 2.60GHz.
+    if [ $status -eq 0 ]; then
+	passes=$(($passes + 1))
+	if [ $passes -ge 10 ]; then
+	    step=$((step * 10))
+	    passes=0
+	fi
+    elif [ $status -eq 1 ]; then
+	passes=0
+	step=1
+    fi
+
+    if [ $status -ne $prev_status ]; then
+	echo "Status changed to $status at $i"
+    fi
+    prev_status=$status
+
+    i=$(($i + $step))
+done
+
+# Success.
+exit 0

libbacktrace/atomic.c

@@ -0,0 +1,113 @@
+/* atomic.c -- Support for atomic functions if not present.
+   Copyright (C) 2013-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+#include "internal.h"
+
+/* This file holds implementations of the atomic functions that are
+   used if the host compiler has the sync functions but not the atomic
+   functions, as is true of versions of GCC before 4.7.  */
+
+#if !defined (HAVE_ATOMIC_FUNCTIONS) && defined (HAVE_SYNC_FUNCTIONS)
+
+/* Do an atomic load of a pointer.  */
+
+void *
+backtrace_atomic_load_pointer (void *arg)
+{
+  void **pp;
+  void *p;
+
+  pp = (void **) arg;
+  p = *pp;
+  while (!__sync_bool_compare_and_swap (pp, p, p))
+    p = *pp;
+  return p;
+}
+
+/* Do an atomic load of an int.  */
+
+int
+backtrace_atomic_load_int (int *p)
+{
+  int i;
+
+  i = *p;
+  while (!__sync_bool_compare_and_swap (p, i, i))
+    i = *p;
+  return i;
+}
+
+/* Do an atomic store of a pointer.  */
+
+void
+backtrace_atomic_store_pointer (void *arg, void *p)
+{
+  void **pp;
+  void *old;
+
+  pp = (void **) arg;
+  old = *pp;
+  while (!__sync_bool_compare_and_swap (pp, old, p))
+    old = *pp;
+}
+
+/* Do an atomic store of a size_t value.  */
+
+void
+backtrace_atomic_store_size_t (size_t *p, size_t v)
+{
+  size_t old;
+
+  old = *p;
+  while (!__sync_bool_compare_and_swap (p, old, v))
+    old = *p;
+}
+
+/* Do an atomic store of a int value.  */
+
+void
+backtrace_atomic_store_int (int *p, int v)
+{
+  size_t old;
+
+  old = *p;
+  while (!__sync_bool_compare_and_swap (p, old, v))
+    old = *p;
+}
+
+#endif

libbacktrace/backtrace-supported.h.in

@@ -0,0 +1,66 @@
+/* backtrace-supported.h.in -- Whether stack backtrace is supported.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* The file backtrace-supported.h.in is used by configure to generate
+   the file backtrace-supported.h.  The file backtrace-supported.h may
+   be #include'd to see whether the backtrace library will be able to
+   get a backtrace and produce symbolic information.  */
+
+
+/* BACKTRACE_SUPPORTED will be #define'd as 1 if the backtrace library
+   should work, 0 if it will not.  Libraries may #include this to make
+   other arrangements.  */
+
+#define BACKTRACE_SUPPORTED @BACKTRACE_SUPPORTED@
+
+/* BACKTRACE_USES_MALLOC will be #define'd as 1 if the backtrace
+   library will call malloc as it works, 0 if it will call mmap
+   instead.  This may be used to determine whether it is safe to call
+   the backtrace functions from a signal handler.  In general this
+   only applies to calls like backtrace and backtrace_pcinfo.  It does
+   not apply to backtrace_simple, which never calls malloc.  It does
+   not apply to backtrace_print, which always calls fprintf and
+   therefore malloc.  */
+
+#define BACKTRACE_USES_MALLOC @BACKTRACE_USES_MALLOC@
+
+/* BACKTRACE_SUPPORTS_THREADS will be #define'd as 1 if the backtrace
+   library is configured with threading support, 0 if not.  If this is
+   0, the threaded parameter to backtrace_create_state must be passed
+   as 0.  */
+
+#define BACKTRACE_SUPPORTS_THREADS @BACKTRACE_SUPPORTS_THREADS@
+
+/* BACKTRACE_SUPPORTS_DATA will be #defined'd as 1 if the backtrace_syminfo
+   will work for variables.  It will always work for functions.  */
+
+#define BACKTRACE_SUPPORTS_DATA @BACKTRACE_SUPPORTS_DATA@

libbacktrace/backtrace.c

@@ -0,0 +1,129 @@
+/* backtrace.c -- Entry point for stack backtrace library.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <sys/types.h>
+
+#include "unwind.h"
+#include "backtrace.h"
+#include "internal.h"
+
+/* The main backtrace_full routine.  */
+
+/* Data passed through _Unwind_Backtrace.  */
+
+struct backtrace_data
+{
+  /* Number of frames to skip.  */
+  int skip;
+  /* Library state.  */
+  struct backtrace_state *state;
+  /* Callback routine.  */
+  backtrace_full_callback callback;
+  /* Error callback routine.  */
+  backtrace_error_callback error_callback;
+  /* Data to pass to callback routines.  */
+  void *data;
+  /* Value to return from backtrace_full.  */
+  int ret;
+  /* Whether there is any memory available.  */
+  int can_alloc;
+};
+
+/* Unwind library callback routine.  This is passed to
+   _Unwind_Backtrace.  */
+
+static _Unwind_Reason_Code
+unwind (struct _Unwind_Context *context, void *vdata)
+{
+  struct backtrace_data *bdata = (struct backtrace_data *) vdata;
+  uintptr_t pc;
+  int ip_before_insn = 0;
+
+#ifdef HAVE_GETIPINFO
+  pc = _Unwind_GetIPInfo (context, &ip_before_insn);
+#else
+  pc = _Unwind_GetIP (context);
+#endif
+
+  if (bdata->skip > 0)
+    {
+      --bdata->skip;
+      return _URC_NO_REASON;
+    }
+
+  if (!ip_before_insn)
+    --pc;
+
+  if (!bdata->can_alloc)
+    bdata->ret = bdata->callback (bdata->data, pc, NULL, 0, NULL);
+  else
+    bdata->ret = backtrace_pcinfo (bdata->state, pc, bdata->callback,
+				   bdata->error_callback, bdata->data);
+  if (bdata->ret != 0)
+    return _URC_END_OF_STACK;
+
+  return _URC_NO_REASON;
+}
+
+/* Get a stack backtrace.  */
+
+int __attribute__((noinline))
+backtrace_full (struct backtrace_state *state, int skip,
+		backtrace_full_callback callback,
+		backtrace_error_callback error_callback, void *data)
+{
+  struct backtrace_data bdata;
+  void *p;
+
+  bdata.skip = skip + 1;
+  bdata.state = state;
+  bdata.callback = callback;
+  bdata.error_callback = error_callback;
+  bdata.data = data;
+  bdata.ret = 0;
+
+  /* If we can't allocate any memory at all, don't try to produce
+     file/line information.  */
+  p = backtrace_alloc (state, 4096, NULL, NULL);
+  if (p == NULL)
+    bdata.can_alloc = 0;
+  else
+    {
+      backtrace_free (state, p, 4096, NULL, NULL);
+      bdata.can_alloc = 1;
+    }
+
+  _Unwind_Backtrace (unwind, &bdata);
+  return bdata.ret;
+}

libbacktrace/backtrace.h

@@ -0,0 +1,206 @@
+/* backtrace.h -- Public header file for stack backtrace library.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#ifndef BACKTRACE_H
+#define BACKTRACE_H
+
+#include <stddef.h>
+#include <stdio.h>
+
+/* We want to get a definition for uintptr_t, but we still care about
+   systems that don't have <stdint.h>.  */
+#if defined(__GLIBC__) && __GLIBC__ >= 2
+
+#include <stdint.h>
+
+#elif defined(HAVE_STDINT_H)
+
+#include <stdint.h>
+
+#else
+
+/* Systems that don't have <stdint.h> must provide gstdint.h, e.g.,
+   from GCC_HEADER_STDINT in configure.ac.  */
+#include "gstdint.h"
+
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* The backtrace state.  This struct is intentionally not defined in
+   the public interface.  */
+
+struct backtrace_state;
+
+/* The type of the error callback argument to backtrace functions.
+   This function, if not NULL, will be called for certain error cases.
+   The DATA argument is passed to the function that calls this one.
+   The MSG argument is an error message.  The ERRNUM argument, if
+   greater than 0, holds an errno value.  The MSG buffer may become
+   invalid after this function returns.
+
+   As a special case, the ERRNUM argument will be passed as -1 if no
+   debug info can be found for the executable, or if the debug info
+   exists but has an unsupported version, but the function requires
+   debug info (e.g., backtrace_full, backtrace_pcinfo).  The MSG in
+   this case will be something along the lines of "no debug info".
+   Similarly, ERRNUM will be passed as -1 if there is no symbol table,
+   but the function requires a symbol table (e.g., backtrace_syminfo).
+   This may be used as a signal that some other approach should be
+   tried.  */
+
+typedef void (*backtrace_error_callback) (void *data, const char *msg,
+					  int errnum);
+
+/* Create state information for the backtrace routines.  This must be
+   called before any of the other routines, and its return value must
+   be passed to all of the other routines.  FILENAME is the path name
+   of the executable file; if it is NULL the library will try
+   system-specific path names.  If not NULL, FILENAME must point to a
+   permanent buffer.  If THREADED is non-zero the state may be
+   accessed by multiple threads simultaneously, and the library will
+   use appropriate atomic operations.  If THREADED is zero the state
+   may only be accessed by one thread at a time.  This returns a state
+   pointer on success, NULL on error.  If an error occurs, this will
+   call the ERROR_CALLBACK routine.
+
+   Calling this function allocates resources that cannot be freed.
+   There is no backtrace_free_state function.  The state is used to
+   cache information that is expensive to recompute.  Programs are
+   expected to call this function at most once and to save the return
+   value for all later calls to backtrace functions.  */
+
+extern struct backtrace_state *backtrace_create_state (
+    const char *filename, int threaded,
+    backtrace_error_callback error_callback, void *data);
+
+/* The type of the callback argument to the backtrace_full function.
+   DATA is the argument passed to backtrace_full.  PC is the program
+   counter.  FILENAME is the name of the file containing PC, or NULL
+   if not available.  LINENO is the line number in FILENAME containing
+   PC, or 0 if not available.  FUNCTION is the name of the function
+   containing PC, or NULL if not available.  This should return 0 to
+   continuing tracing.  The FILENAME and FUNCTION buffers may become
+   invalid after this function returns.  */
+
+typedef int (*backtrace_full_callback) (void *data, uintptr_t pc,
+					const char *filename, int lineno,
+					const char *function);
+
+/* Get a full stack backtrace.  SKIP is the number of frames to skip;
+   passing 0 will start the trace with the function calling
+   backtrace_full.  DATA is passed to the callback routine.  If any
+   call to CALLBACK returns a non-zero value, the stack backtrace
+   stops, and backtrace returns that value; this may be used to limit
+   the number of stack frames desired.  If all calls to CALLBACK
+   return 0, backtrace returns 0.  The backtrace_full function will
+   make at least one call to either CALLBACK or ERROR_CALLBACK.  This
+   function requires debug info for the executable.  */
+
+extern int backtrace_full (struct backtrace_state *state, int skip,
+			   backtrace_full_callback callback,
+			   backtrace_error_callback error_callback,
+			   void *data);
+
+/* The type of the callback argument to the backtrace_simple function.
+   DATA is the argument passed to simple_backtrace.  PC is the program
+   counter.  This should return 0 to continue tracing.  */
+
+typedef int (*backtrace_simple_callback) (void *data, uintptr_t pc);
+
+/* Get a simple backtrace.  SKIP is the number of frames to skip, as
+   in backtrace.  DATA is passed to the callback routine.  If any call
+   to CALLBACK returns a non-zero value, the stack backtrace stops,
+   and backtrace_simple returns that value.  Otherwise
+   backtrace_simple returns 0.  The backtrace_simple function will
+   make at least one call to either CALLBACK or ERROR_CALLBACK.  This
+   function does not require any debug info for the executable.  */
+
+extern int backtrace_simple (struct backtrace_state *state, int skip,
+			     backtrace_simple_callback callback,
+			     backtrace_error_callback error_callback,
+			     void *data);
+
+/* Print the current backtrace in a user readable format to a FILE.
+   SKIP is the number of frames to skip, as in backtrace_full.  Any
+   error messages are printed to stderr.  This function requires debug
+   info for the executable.  */
+
+extern void backtrace_print (struct backtrace_state *state, int skip, FILE *);
+
+/* Given PC, a program counter in the current program, call the
+   callback function with filename, line number, and function name
+   information.  This will normally call the callback function exactly
+   once.  However, if the PC happens to describe an inlined call, and
+   the debugging information contains the necessary information, then
+   this may call the callback function multiple times.  This will make
+   at least one call to either CALLBACK or ERROR_CALLBACK.  This
+   returns the first non-zero value returned by CALLBACK, or 0.  */
+
+extern int backtrace_pcinfo (struct backtrace_state *state, uintptr_t pc,
+			     backtrace_full_callback callback,
+			     backtrace_error_callback error_callback,
+			     void *data);
+
+/* The type of the callback argument to backtrace_syminfo.  DATA and
+   PC are the arguments passed to backtrace_syminfo.  SYMNAME is the
+   name of the symbol for the corresponding code.  SYMVAL is the
+   value and SYMSIZE is the size of the symbol.  SYMNAME will be NULL
+   if no error occurred but the symbol could not be found.  */
+
+typedef void (*backtrace_syminfo_callback) (void *data, uintptr_t pc,
+					    const char *symname,
+					    uintptr_t symval,
+					    uintptr_t symsize);
+
+/* Given ADDR, an address or program counter in the current program,
+   call the callback information with the symbol name and value
+   describing the function or variable in which ADDR may be found.
+   This will call either CALLBACK or ERROR_CALLBACK exactly once.
+   This returns 1 on success, 0 on failure.  This function requires
+   the symbol table but does not require the debug info.  Note that if
+   the symbol table is present but ADDR could not be found in the
+   table, CALLBACK will be called with a NULL SYMNAME argument.
+   Returns 1 on success, 0 on error.  */
+
+extern int backtrace_syminfo (struct backtrace_state *state, uintptr_t addr,
+			      backtrace_syminfo_callback callback,
+			      backtrace_error_callback error_callback,
+			      void *data);
+
+#ifdef __cplusplus
+} /* End extern "C".  */
+#endif
+
+#endif

libbacktrace/btest.c

@@ -0,0 +1,501 @@
+/* btest.c -- Test for libbacktrace library
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* This program tests the externally visible interfaces of the
+   libbacktrace library.  */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "filenames.h"
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "testlib.h"
+
+/* Test the backtrace function with non-inlined functions.  */
+
+static int test1 (void) __attribute__ ((noinline, noclone, unused));
+static int f2 (int) __attribute__ ((noinline, noclone));
+static int f3 (int, int) __attribute__ ((noinline, noclone));
+
+static int
+test1 (void)
+{
+  /* Returning a value here and elsewhere avoids a tailcall which
+     would mess up the backtrace.  */
+  return f2 (__LINE__) + 1;
+}
+
+static int
+f2 (int f1line)
+{
+  return f3 (f1line, __LINE__) + 2;
+}
+
+static int
+f3 (int f1line, int f2line)
+{
+  struct info all[20];
+  struct bdata data;
+  int f3line;
+  int i;
+
+  data.all = &all[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_full (state, 0, callback_one, error_callback_one, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test1: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (data.index < 3)
+    {
+      fprintf (stderr,
+	       "test1: not enough frames; got %zu, expected at least 3\n",
+	       data.index);
+      data.failed = 1;
+    }
+
+  check ("test1", 0, all, f3line, "f3", "btest.c", &data.failed);
+  check ("test1", 1, all, f2line, "f2", "btest.c", &data.failed);
+  check ("test1", 2, all, f1line, "test1", "btest.c", &data.failed);
+
+  printf ("%s: backtrace_full noinline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Test the backtrace function with inlined functions.  */
+
+static inline int test2 (void) __attribute__ ((always_inline, unused));
+static inline int f12 (int) __attribute__ ((always_inline));
+static inline int f13 (int, int) __attribute__ ((always_inline));
+
+static inline int
+test2 (void)
+{
+  return f12 (__LINE__) + 1;
+}
+
+static inline int
+f12 (int f1line)
+{
+  return f13 (f1line, __LINE__) + 2;
+}
+
+static inline int
+f13 (int f1line, int f2line)
+{
+  struct info all[20];
+  struct bdata data;
+  int f3line;
+  int i;
+
+  data.all = &all[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_full (state, 0, callback_one, error_callback_one, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test2: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  check ("test2", 0, all, f3line, "f13", "btest.c", &data.failed);
+  check ("test2", 1, all, f2line, "f12", "btest.c", &data.failed);
+  check ("test2", 2, all, f1line, "test2", "btest.c", &data.failed);
+
+  printf ("%s: backtrace_full inline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Test the backtrace_simple function with non-inlined functions.  */
+
+static int test3 (void) __attribute__ ((noinline, noclone, unused));
+static int f22 (int) __attribute__ ((noinline, noclone));
+static int f23 (int, int) __attribute__ ((noinline, noclone));
+
+static int
+test3 (void)
+{
+  return f22 (__LINE__) + 1;
+}
+
+static int
+f22 (int f1line)
+{
+  return f23 (f1line, __LINE__) + 2;
+}
+
+static int
+f23 (int f1line, int f2line)
+{
+  uintptr_t addrs[20];
+  struct sdata data;
+  int f3line;
+  int i;
+
+  data.addrs = &addrs[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_simple (state, 0, callback_two, error_callback_two, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test3: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (!data.failed)
+    {
+      struct info all[20];
+      struct bdata bdata;
+      int j;
+
+      bdata.all = &all[0];
+      bdata.index = 0;
+      bdata.max = 20;
+      bdata.failed = 0;
+
+      for (j = 0; j < 3; ++j)
+	{
+	  i = backtrace_pcinfo (state, addrs[j], callback_one,
+				error_callback_one, &bdata);
+	  if (i != 0)
+	    {
+	      fprintf (stderr,
+		       ("test3: unexpected return value "
+			"from backtrace_pcinfo %d\n"),
+		       i);
+	      bdata.failed = 1;
+	    }
+	  if (!bdata.failed && bdata.index != (size_t) (j + 1))
+	    {
+	      fprintf (stderr,
+		       ("wrong number of calls from backtrace_pcinfo "
+			"got %u expected %d\n"),
+		       (unsigned int) bdata.index, j + 1);
+	      bdata.failed = 1;
+	    }
+	}
+
+      check ("test3", 0, all, f3line, "f23", "btest.c", &bdata.failed);
+      check ("test3", 1, all, f2line, "f22", "btest.c", &bdata.failed);
+      check ("test3", 2, all, f1line, "test3", "btest.c", &bdata.failed);
+
+      if (bdata.failed)
+	data.failed = 1;
+
+      for (j = 0; j < 3; ++j)
+	{
+	  struct symdata symdata;
+
+	  symdata.name = NULL;
+	  symdata.val = 0;
+	  symdata.size = 0;
+	  symdata.failed = 0;
+
+	  i = backtrace_syminfo (state, addrs[j], callback_three,
+				 error_callback_three, &symdata);
+	  if (i == 0)
+	    {
+	      fprintf (stderr,
+		       ("test3: [%d]: unexpected return value "
+			"from backtrace_syminfo %d\n"),
+		       j, i);
+	      symdata.failed = 1;
+	    }
+
+	  if (!symdata.failed)
+	    {
+	      const char *expected;
+
+	      switch (j)
+		{
+		case 0:
+		  expected = "f23";
+		  break;
+		case 1:
+		  expected = "f22";
+		  break;
+		case 2:
+		  expected = "test3";
+		  break;
+		default:
+		  assert (0);
+		}
+
+	      if (symdata.name == NULL)
+		{
+		  fprintf (stderr, "test3: [%d]: NULL syminfo name\n", j);
+		  symdata.failed = 1;
+		}
+	      /* Use strncmp, not strcmp, because GCC might create a
+		 clone.  */
+	      else if (strncmp (symdata.name, expected, strlen (expected))
+		       != 0)
+		{
+		  fprintf (stderr,
+			   ("test3: [%d]: unexpected syminfo name "
+			    "got %s expected %s\n"),
+			   j, symdata.name, expected);
+		  symdata.failed = 1;
+		}
+	    }
+
+	  if (symdata.failed)
+	    data.failed = 1;
+	}
+    }
+
+  printf ("%s: backtrace_simple noinline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Test the backtrace_simple function with inlined functions.  */
+
+static inline int test4 (void) __attribute__ ((always_inline, unused));
+static inline int f32 (int) __attribute__ ((always_inline));
+static inline int f33 (int, int) __attribute__ ((always_inline));
+
+static inline int
+test4 (void)
+{
+  return f32 (__LINE__) + 1;
+}
+
+static inline int
+f32 (int f1line)
+{
+  return f33 (f1line, __LINE__) + 2;
+}
+
+static inline int
+f33 (int f1line, int f2line)
+{
+  uintptr_t addrs[20];
+  struct sdata data;
+  int f3line;
+  int i;
+
+  data.addrs = &addrs[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_simple (state, 0, callback_two, error_callback_two, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test3: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (!data.failed)
+    {
+      struct info all[20];
+      struct bdata bdata;
+
+      bdata.all = &all[0];
+      bdata.index = 0;
+      bdata.max = 20;
+      bdata.failed = 0;
+
+      i = backtrace_pcinfo (state, addrs[0], callback_one, error_callback_one,
+			    &bdata);
+      if (i != 0)
+	{
+	  fprintf (stderr,
+		   ("test4: unexpected return value "
+		    "from backtrace_pcinfo %d\n"),
+		   i);
+	  bdata.failed = 1;
+	}
+
+      check ("test4", 0, all, f3line, "f33", "btest.c", &bdata.failed);
+      check ("test4", 1, all, f2line, "f32", "btest.c", &bdata.failed);
+      check ("test4", 2, all, f1line, "test4", "btest.c", &bdata.failed);
+
+      if (bdata.failed)
+	data.failed = 1;
+    }
+
+  printf ("%s: backtrace_simple inline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+static int test5 (void) __attribute__ ((unused));
+
+int global = 1;
+
+static int
+test5 (void)
+{
+  struct symdata symdata;
+  int i;
+  uintptr_t addr = (uintptr_t) &global;
+
+  if (sizeof (global) > 1)
+    addr += 1;
+
+  symdata.name = NULL;
+  symdata.val = 0;
+  symdata.size = 0;
+  symdata.failed = 0;
+
+  i = backtrace_syminfo (state, addr, callback_three,
+			 error_callback_three, &symdata);
+  if (i == 0)
+    {
+      fprintf (stderr,
+	       "test5: unexpected return value from backtrace_syminfo %d\n",
+	       i);
+      symdata.failed = 1;
+    }
+
+  if (!symdata.failed)
+    {
+      if (symdata.name == NULL)
+	{
+	  fprintf (stderr, "test5: NULL syminfo name\n");
+	  symdata.failed = 1;
+	}
+      else if (!(strncmp (symdata.name, "global", 6) == 0
+		 && (symdata.name[6] == '\0'|| symdata.name[6] == '.')))
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo name got %s expected %s\n",
+		   symdata.name, "global");
+	  symdata.failed = 1;
+	}
+      else if (symdata.val != (uintptr_t) &global)
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo value got %lx expected %lx\n",
+		   (unsigned long) symdata.val,
+		   (unsigned long) (uintptr_t) &global);
+	  symdata.failed = 1;
+	}
+      else if (symdata.size != sizeof (global))
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo size got %lx expected %lx\n",
+		   (unsigned long) symdata.size,
+		   (unsigned long) sizeof (global));
+	  symdata.failed = 1;
+	}
+    }
+
+  printf ("%s: backtrace_syminfo variable\n",
+	  symdata.failed ? "FAIL" : "PASS");
+
+  if (symdata.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Check that are no files left open.  */
+
+static void
+check_open_files (void)
+{
+  int i;
+
+  for (i = 3; i < 10; i++)
+    {
+      if (close (i) == 0)
+	{
+	  fprintf (stderr,
+		   "ERROR: descriptor %d still open after tests complete\n",
+		   i);
+	  ++failures;
+	}
+    }
+}
+
+/* Run all the tests.  */
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+#if BACKTRACE_SUPPORTED
+  test1 ();
+  test2 ();
+  test3 ();
+  test4 ();
+#if BACKTRACE_SUPPORTS_DATA
+  test5 ();
+#endif
+#endif
+
+  check_open_files ();
+
+  exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/config.h.in

@@ -0,0 +1,184 @@
+/* config.h.in.  Generated from configure.ac by autoheader.  */
+
+/* ELF size: 32 or 64 */
+#undef BACKTRACE_ELF_SIZE
+
+/* XCOFF size: 32 or 64 */
+#undef BACKTRACE_XCOFF_SIZE
+
+/* Define to 1 if you have the __atomic functions */
+#undef HAVE_ATOMIC_FUNCTIONS
+
+/* Define to 1 if you have the `clock_gettime' function. */
+#undef HAVE_CLOCK_GETTIME
+
+/* Define to 1 if you have the declaration of `getpagesize', and to 0 if you
+   don't. */
+#undef HAVE_DECL_GETPAGESIZE
+
+/* Define to 1 if you have the declaration of `strnlen', and to 0 if you
+   don't. */
+#undef HAVE_DECL_STRNLEN
+
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#undef HAVE_DLFCN_H
+
+/* Define if dl_iterate_phdr is available. */
+#undef HAVE_DL_ITERATE_PHDR
+
+/* Define to 1 if you have the fcntl function */
+#undef HAVE_FCNTL
+
+/* Define if getexecname is available. */
+#undef HAVE_GETEXECNAME
+
+/* Define if _Unwind_GetIPInfo is available. */
+#undef HAVE_GETIPINFO
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#undef HAVE_INTTYPES_H
+
+/* Define to 1 if you have KERN_PROC and KERN_PROC_PATHNAME in <sys/sysctl.h>.
+   */
+#undef HAVE_KERN_PROC
+
+/* Define to 1 if you have KERN_PROCARGS and KERN_PROC_PATHNAME in
+   <sys/sysctl.h>. */
+#undef HAVE_KERN_PROC_ARGS
+
+/* Define if -llzma is available. */
+#undef HAVE_LIBLZMA
+
+/* Define to 1 if you have the <link.h> header file. */
+#undef HAVE_LINK_H
+
+/* Define if AIX loadquery is available. */
+#undef HAVE_LOADQUERY
+
+/* Define to 1 if you have the `lstat' function. */
+#undef HAVE_LSTAT
+
+/* Define to 1 if you have the <mach-o/dyld.h> header file. */
+#undef HAVE_MACH_O_DYLD_H
+
+/* Define to 1 if you have the <memory.h> header file. */
+#undef HAVE_MEMORY_H
+
+/* Define to 1 if you have the `readlink' function. */
+#undef HAVE_READLINK
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#undef HAVE_STDINT_H
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#undef HAVE_STDLIB_H
+
+/* Define to 1 if you have the <strings.h> header file. */
+#undef HAVE_STRINGS_H
+
+/* Define to 1 if you have the <string.h> header file. */
+#undef HAVE_STRING_H
+
+/* Define to 1 if you have the __sync functions */
+#undef HAVE_SYNC_FUNCTIONS
+
+/* Define to 1 if you have the <sys/ldr.h> header file. */
+#undef HAVE_SYS_LDR_H
+
+/* Define to 1 if you have the <sys/mman.h> header file. */
+#undef HAVE_SYS_MMAN_H
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#undef HAVE_SYS_STAT_H
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#undef HAVE_SYS_TYPES_H
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#undef HAVE_UNISTD_H
+
+/* Define if -lz is available. */
+#undef HAVE_ZLIB
+
+/* Define to the sub-directory in which libtool stores uninstalled libraries.
+   */
+#undef LT_OBJDIR
+
+/* Define to the address where bug reports for this package should be sent. */
+#undef PACKAGE_BUGREPORT
+
+/* Define to the full name of this package. */
+#undef PACKAGE_NAME
+
+/* Define to the full name and version of this package. */
+#undef PACKAGE_STRING
+
+/* Define to the one symbol short name of this package. */
+#undef PACKAGE_TARNAME
+
+/* Define to the home page for this package. */
+#undef PACKAGE_URL
+
+/* Define to the version of this package. */
+#undef PACKAGE_VERSION
+
+/* The size of `char', as computed by sizeof. */
+#undef SIZEOF_CHAR
+
+/* The size of `int', as computed by sizeof. */
+#undef SIZEOF_INT
+
+/* The size of `long', as computed by sizeof. */
+#undef SIZEOF_LONG
+
+/* The size of `short', as computed by sizeof. */
+#undef SIZEOF_SHORT
+
+/* The size of `void *', as computed by sizeof. */
+#undef SIZEOF_VOID_P
+
+/* Define to 1 if you have the ANSI C header files. */
+#undef STDC_HEADERS
+
+/* Enable extensions on AIX 3, Interix.  */
+#ifndef _ALL_SOURCE
+# undef _ALL_SOURCE
+#endif
+/* Enable GNU extensions on systems that have them.  */
+#ifndef _GNU_SOURCE
+# undef _GNU_SOURCE
+#endif
+/* Enable threading extensions on Solaris.  */
+#ifndef _POSIX_PTHREAD_SEMANTICS
+# undef _POSIX_PTHREAD_SEMANTICS
+#endif
+/* Enable extensions on HP NonStop.  */
+#ifndef _TANDEM_SOURCE
+# undef _TANDEM_SOURCE
+#endif
+/* Enable general extensions on Solaris.  */
+#ifndef __EXTENSIONS__
+# undef __EXTENSIONS__
+#endif
+
+
+/* Enable large inode numbers on Mac OS X 10.5.  */
+#ifndef _DARWIN_USE_64_BIT_INODE
+# define _DARWIN_USE_64_BIT_INODE 1
+#endif
+
+/* Number of bits in a file offset, on hosts where this is settable. */
+#undef _FILE_OFFSET_BITS
+
+/* Define for large files, on AIX-style hosts. */
+#undef _LARGE_FILES
+
+/* Define to 1 if on MINIX. */
+#undef _MINIX
+
+/* Define to 2 if the system does not provide POSIX.1 features except with
+   this defined. */
+#undef _POSIX_1_SOURCE
+
+/* Define to 1 if you need to in order for `stat' and other things to work. */
+#undef _POSIX_SOURCE

libbacktrace/configure.ac

@@ -0,0 +1,581 @@
+# configure.ac -- Backtrace configure script.
+# Copyright (C) 2012-2021 Free Software Foundation, Inc.
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+
+#     (1) Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+
+#     (2) Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+
+#     (3) The name of the author may not be used to
+#     endorse or promote products derived from this software without
+#     specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+AC_INIT(package-unused, version-unused,, libbacktrace)
+AC_CONFIG_SRCDIR(backtrace.h)
+AC_CONFIG_HEADER(config.h)
+
+if test -n "${with_target_subdir}"; then
+  AM_ENABLE_MULTILIB(, ..)
+fi
+
+AC_CANONICAL_SYSTEM
+target_alias=${target_alias-$host_alias}
+
+AC_USE_SYSTEM_EXTENSIONS
+
+libtool_VERSION=1:0:0
+AC_SUBST(libtool_VERSION)
+
+# 1.11.1: Require that version of automake.
+# foreign: Don't require README, INSTALL, NEWS, etc.
+# no-define: Don't define PACKAGE and VERSION.
+# no-dependencies: Don't generate automatic dependencies.
+#    (because it breaks when using bootstrap-lean, since some of the
+#    headers are gone at "make install" time).
+# -Wall: Issue all automake warnings.
+# -Wno-portability: Don't warn about constructs supported by GNU make.
+#    (because GCC requires GNU make anyhow).
+AM_INIT_AUTOMAKE([1.11.1 foreign no-dist no-define no-dependencies -Wall -Wno-portability])
+
+AM_MAINTAINER_MODE
+
+AC_ARG_WITH(target-subdir,
+[  --with-target-subdir=SUBDIR      Configuring in a subdirectory for target])
+
+# We must force CC to /not/ be precious variables; otherwise
+# the wrong, non-multilib-adjusted value will be used in multilibs.
+# As a side effect, we have to subst CFLAGS ourselves.
+m4_rename([_AC_ARG_VAR_PRECIOUS],[backtrace_PRECIOUS])
+m4_define([_AC_ARG_VAR_PRECIOUS],[])
+AC_PROG_CC
+m4_rename_force([backtrace_PRECIOUS],[_AC_ARG_VAR_PRECIOUS])
+
+AC_SUBST(CFLAGS)
+
+AC_PROG_RANLIB
+
+AC_PROG_AWK
+case "$AWK" in
+"") AC_MSG_ERROR([can't build without awk]) ;;
+esac
+
+AC_CHECK_PROG(DWZ, dwz, dwz)
+AM_CONDITIONAL(HAVE_DWZ, test "$DWZ" != "")
+
+LT_INIT
+AM_PROG_LIBTOOL
+
+AC_SYS_LARGEFILE
+
+backtrace_supported=yes
+
+if test -n "${with_target_subdir}"; then
+  # We are compiling a GCC library.  We can assume that the unwind
+  # library exists.
+  BACKTRACE_FILE="backtrace.lo simple.lo"
+else
+  AC_CHECK_HEADER([unwind.h],
+    [AC_CHECK_FUNC([_Unwind_Backtrace],
+	           [BACKTRACE_FILE="backtrace.lo simple.lo"],
+		   [BACKTRACE_FILE="nounwind.lo"
+                    backtrace_supported=no])],
+    [BACKTRACE_FILE="nounwind.lo"
+     backtrace_supported=no])
+fi
+AC_SUBST(BACKTRACE_FILE)
+
+EXTRA_FLAGS=
+if test -n "${with_target_subdir}"; then
+  EXTRA_FLAGS="-funwind-tables -frandom-seed=\$@"
+else
+  AC_CACHE_CHECK([for -funwind-tables option],
+    [libbacktrace_cv_c_unwind_tables],
+    [CFLAGS_hold="$CFLAGS"
+     CFLAGS="$CFLAGS -funwind-tables"
+     AC_COMPILE_IFELSE(
+       [AC_LANG_PROGRAM([static int f() { return 0; }], [return f();])],
+       [libbacktrace_cv_c_unwind_tables=yes],
+       [libbacktrace_cv_c_unwind_tables=no])
+     CFLAGS="$CFLAGS_hold"])
+  if test "$libbacktrace_cv_c_unwind_tables" = "yes"; then
+    EXTRA_FLAGS=-funwind-tables
+  fi
+  AC_CACHE_CHECK([for -frandom-seed=string option],
+    [libbacktrace_cv_c_random_seed_string],
+    [CFLAGS_hold="$CFLAGS"
+     CFLAGS="$CFLAGS -frandom-seed=conftest.lo"
+     AC_COMPILE_IFELSE(
+       [AC_LANG_PROGRAM([], [return 0;])],
+       [libbacktrace_cv_c_random_seed_string=yes],
+       [libbacktrace_cv_c_random_seed_string=no])
+     CFLAGS="$CFLAGS_hold"])
+  if test "$libbacktrace_cv_c_random_seed_string" = "yes"; then
+    EXTRA_FLAGS="$EXTRA_FLAGS -frandom-seed=\$@"
+  fi
+fi
+
+if test -n "${with_target_subdir}"; then
+  # Add CET specific flags is Intel CET is enabled.
+  GCC_CET_FLAGS(CET_FLAGS)
+  EXTRA_FLAGS="$EXTRA_FLAGS $CET_FLAGS"
+fi
+AC_SUBST(EXTRA_FLAGS)
+
+ACX_PROG_CC_WARNING_OPTS([-W -Wall -Wwrite-strings -Wstrict-prototypes \
+			  -Wmissing-prototypes -Wold-style-definition \
+			  -Wmissing-format-attribute -Wcast-qual],
+			  [WARN_FLAGS])
+
+if test -n "${with_target_subdir}"; then
+  WARN_FLAGS="$WARN_FLAGS -Werror"
+fi
+
+AC_SUBST(WARN_FLAGS)
+
+if test -n "${with_target_subdir}"; then
+  GCC_CHECK_UNWIND_GETIPINFO
+else
+  ac_save_CFFLAGS="$CFLAGS"
+  CFLAGS="$CFLAGS -Werror-implicit-function-declaration"
+  AC_MSG_CHECKING([for _Unwind_GetIPInfo])
+  AC_LINK_IFELSE(
+    [AC_LANG_PROGRAM(
+       [#include "unwind.h"
+	struct _Unwind_Context *context;
+	int ip_before_insn = 0;],
+	[return _Unwind_GetIPInfo (context, &ip_before_insn);])],
+	[have_unwind_getipinfo=yes], [have_unwind_getipinfo=no])
+  CFLAGS="$ac_save_CFLAGS"
+  AC_MSG_RESULT([$have_unwind_getipinfo])
+  if test "$have_unwind_getipinfo" = "yes"; then
+    AC_DEFINE(HAVE_GETIPINFO, 1, [Define if _Unwind_GetIPInfo is available.])
+  fi
+fi
+
+# Enable --enable-host-shared.
+AC_ARG_ENABLE(host-shared,
+[AS_HELP_STRING([--enable-host-shared],
+		[build host code as shared libraries])],
+[PIC_FLAG=-fPIC], [PIC_FLAG=])
+AC_SUBST(PIC_FLAG)
+
+# Enable Intel CET on Intel CET enabled host if jit is enabled.
+GCC_CET_HOST_FLAGS(CET_HOST_FLAGS)
+case x$enable_languages in
+*jit*)
+  ;;
+*)
+  CET_HOST_FLAGS=
+  ;;
+esac
+AC_SUBST(CET_HOST_FLAGS)
+
+# Test for __sync support.
+AC_CACHE_CHECK([__sync extensions],
+[libbacktrace_cv_sys_sync],
+[if test -n "${with_target_subdir}"; then
+   case "${host}" in
+   hppa*-*-hpux*) libbacktrace_cv_sys_sync=no ;;
+   *) libbacktrace_cv_sys_sync=yes ;;
+   esac
+ else
+   AC_LINK_IFELSE(
+     [AC_LANG_PROGRAM([int i;],
+                      [__sync_bool_compare_and_swap (&i, i, i);
+                       __sync_lock_test_and_set (&i, 1);
+                       __sync_lock_release (&i);])],
+     [libbacktrace_cv_sys_sync=yes],
+     [libbacktrace_cv_sys_sync=no])
+ fi])
+BACKTRACE_SUPPORTS_THREADS=0
+if test "$libbacktrace_cv_sys_sync" = "yes"; then
+  BACKTRACE_SUPPORTS_THREADS=1
+  AC_DEFINE([HAVE_SYNC_FUNCTIONS], 1,
+	    [Define to 1 if you have the __sync functions])
+fi
+AC_SUBST(BACKTRACE_SUPPORTS_THREADS)
+
+# Test for __atomic support.
+AC_CACHE_CHECK([__atomic extensions],
+[libbacktrace_cv_sys_atomic],
+[if test -n "${with_target_subdir}"; then
+   libbacktrace_cv_sys_atomic=yes
+ else
+   AC_LINK_IFELSE(
+     [AC_LANG_PROGRAM([int i;],
+     		      [__atomic_load_n (&i, __ATOMIC_ACQUIRE);
+		       __atomic_store_n (&i, 1, __ATOMIC_RELEASE);])],
+     [libbacktrace_cv_sys_atomic=yes],
+     [libbacktrace_cv_sys_atomic=no])
+ fi])
+if test "$libbacktrace_cv_sys_atomic" = "yes"; then
+  AC_DEFINE([HAVE_ATOMIC_FUNCTIONS], 1,
+	    [Define to 1 if you have the __atomic functions])
+fi
+
+# The library needs to be able to read the executable itself.  Compile
+# a file to determine the executable format.  The awk script
+# filetype.awk prints out the file type.
+AC_CACHE_CHECK([output filetype],
+[libbacktrace_cv_sys_filetype],
+[filetype=
+AC_COMPILE_IFELSE(
+  [AC_LANG_PROGRAM([int i;], [int j;])],
+  [filetype=`${AWK} -f $srcdir/filetype.awk conftest.$ac_objext`],
+  [AC_MSG_FAILURE([compiler failed])])
+libbacktrace_cv_sys_filetype=$filetype])
+
+# Match the file type to decide what files to compile.
+FORMAT_FILE=
+backtrace_supports_data=yes
+case "$libbacktrace_cv_sys_filetype" in
+elf*) FORMAT_FILE="elf.lo" ;;
+macho) FORMAT_FILE="macho.lo" ;;
+pecoff) FORMAT_FILE="pecoff.lo"
+        backtrace_supports_data=no
+	;;
+xcoff*) FORMAT_FILE="xcoff.lo"
+        backtrace_supports_data=no
+        ;;
+*) AC_MSG_WARN([could not determine output file type])
+   FORMAT_FILE="unknown.lo"
+   backtrace_supported=no
+   ;;
+esac
+AC_SUBST(FORMAT_FILE)
+
+# ELF defines.
+elfsize=
+case "$libbacktrace_cv_sys_filetype" in
+elf32) elfsize=32 ;;
+elf64) elfsize=64 ;;
+*)     elfsize=unused
+esac
+AC_DEFINE_UNQUOTED([BACKTRACE_ELF_SIZE], [$elfsize], [ELF size: 32 or 64])
+AM_CONDITIONAL(HAVE_ELF, test "$FORMAT_FILE" = "elf.lo")
+
+# XCOFF defines.
+xcoffsize=
+case "$libbacktrace_cv_sys_filetype" in
+xcoff32) xcoffsize=32 ;;
+xcoff64) xcoffsize=64 ;;
+*)       xcoffsize=unused
+esac
+AC_DEFINE_UNQUOTED([BACKTRACE_XCOFF_SIZE], [$xcoffsize], [XCOFF size: 32 or 64])
+
+BACKTRACE_SUPPORTED=0
+if test "$backtrace_supported" = "yes"; then
+  BACKTRACE_SUPPORTED=1
+fi
+AC_SUBST(BACKTRACE_SUPPORTED)
+
+BACKTRACE_SUPPORTS_DATA=0
+if test "$backtrace_supports_data" = "yes"; then
+  BACKTRACE_SUPPORTS_DATA=1
+fi
+AC_SUBST(BACKTRACE_SUPPORTS_DATA)
+
+GCC_HEADER_STDINT(gstdint.h)
+
+AC_CHECK_HEADERS(sys/mman.h)
+if test "$ac_cv_header_sys_mman_h" = "no"; then
+  have_mmap=no
+else
+  if test -n "${with_target_subdir}"; then
+    # When built as a GCC target library, we can't do a link test.  We
+    # simply assume that if we have mman.h, we have mmap.
+    have_mmap=yes
+    case "${host}" in
+    *-*-msdosdjgpp)
+        # DJGPP has sys/man.h, but no mmap
+	have_mmap=no ;;
+    esac
+  else
+    AC_CHECK_FUNC(mmap, [have_mmap=yes], [have_mmap=no])
+  fi
+fi
+if test "$have_mmap" = "no"; then
+  VIEW_FILE=read.lo
+  ALLOC_FILE=alloc.lo
+else
+  VIEW_FILE=mmapio.lo
+  AC_PREPROC_IFELSE([AC_LANG_SOURCE([
+#include <sys/mman.h>
+#if !defined(MAP_ANONYMOUS) && !defined(MAP_ANON)
+  #error no MAP_ANONYMOUS
+#endif
+])], [ALLOC_FILE=mmap.lo], [ALLOC_FILE=alloc.lo])
+fi
+AC_SUBST(VIEW_FILE)
+AC_SUBST(ALLOC_FILE)
+
+BACKTRACE_USES_MALLOC=0
+if test "$ALLOC_FILE" = "alloc.lo"; then
+  BACKTRACE_USES_MALLOC=1
+fi
+AC_SUBST(BACKTRACE_USES_MALLOC)
+
+# Check for dl_iterate_phdr.
+AC_CHECK_HEADERS(link.h)
+if test "$ac_cv_header_link_h" = "no"; then
+  have_dl_iterate_phdr=no
+else
+  if test -n "${with_target_subdir}"; then
+    # When built as a GCC target library, we can't do a link test.
+    AC_EGREP_HEADER([dl_iterate_phdr], [link.h], [have_dl_iterate_phdr=yes],
+		    [have_dl_iterate_phdr=no])
+  else
+    AC_CHECK_FUNC([dl_iterate_phdr], [have_dl_iterate_phdr=yes],
+		  [have_dl_iterate_phdr=no])
+  fi
+fi
+if test "$have_dl_iterate_phdr" = "yes"; then
+  AC_DEFINE(HAVE_DL_ITERATE_PHDR, 1, [Define if dl_iterate_phdr is available.])
+fi
+
+# Check for header file for Mach-O image functions.
+AC_CHECK_HEADERS(mach-o/dyld.h)
+
+# Check for loadquery.
+AC_CHECK_HEADERS(sys/ldr.h)
+if test "$ac_cv_header_sys_ldr_h" = "no"; then
+  have_loadquery=no
+else
+  if test -n "${with_target_subdir}"; then
+    # When built as a GCC target library, we can't do a link test.
+    AC_EGREP_HEADER([loadquery], [sys/ldr.h], [have_loadquery=yes],
+		    [have_loadquery=no])
+  else
+    AC_CHECK_FUNC([loadquery], [have_loadquery=yes],
+		  [have_loadquery=no])
+  fi
+fi
+if test "$have_loadquery" = "yes"; then
+  AC_DEFINE(HAVE_LOADQUERY, 1, [Define if AIX loadquery is available.])
+fi
+
+# Check for the fcntl function.
+if test -n "${with_target_subdir}"; then
+   case "${host}" in
+   *-*-mingw*) have_fcntl=no ;;
+   *) have_fcntl=yes ;;
+   esac
+else
+  AC_CHECK_FUNC(fcntl, [have_fcntl=yes], [have_fcntl=no])
+fi
+if test "$have_fcntl" = "yes"; then
+  AC_DEFINE([HAVE_FCNTL], 1,
+	    [Define to 1 if you have the fcntl function])
+fi
+
+AC_CHECK_DECLS([strnlen, getpagesize])
+AC_CHECK_FUNCS(lstat readlink)
+
+# Check for getexecname function.
+if test -n "${with_target_subdir}"; then
+   case "${host}" in
+   *-*-solaris2*) have_getexecname=yes ;;
+   *) have_getexecname=no ;;
+   esac
+else
+  AC_CHECK_FUNC(getexecname, [have_getexecname=yes], [have_getexecname=no])
+fi
+if test "$have_getexecname" = "yes"; then
+  AC_DEFINE(HAVE_GETEXECNAME, 1, [Define if getexecname is available.])
+fi
+
+# Check for sysctl definitions.
+
+AC_CACHE_CHECK([for KERN_PROC],
+[libbacktrace_cv_proc],
+[AC_COMPILE_IFELSE(
+  [AC_LANG_PROGRAM([
+#include <sys/types.h>
+#include <sys/sysctl.h>
+], [int mib0 = CTL_KERN; int mib1 = KERN_PROC; int mib2 = KERN_PROC_PATHNAME;])],
+  [libbacktrace_cv_proc=yes],
+  [libbacktrace_cv_proc=no])])
+if test "$libbacktrace_cv_proc" = "yes"; then
+  AC_DEFINE([HAVE_KERN_PROC], 1,
+            [Define to 1 if you have KERN_PROC and KERN_PROC_PATHNAME in <sys/sysctl.h>.])
+fi
+
+AC_CACHE_CHECK([for KERN_PROG_ARGS],
+[libbacktrace_cv_procargs],
+[AC_COMPILE_IFELSE(
+  [AC_LANG_PROGRAM([
+#include <sys/types.h>
+#include <sys/sysctl.h>
+], [int mib0 = CTL_KERN; int mib1 = KERN_PROC_ARGS; int mib2 = KERN_PROC_PATHNAME;])],
+  [libbacktrace_cv_procargs=yes],
+  [libbacktrace_cv_procargs=no])])
+if test "$libbacktrace_cv_procargs" = "yes"; then
+  AC_DEFINE([HAVE_KERN_PROC_ARGS], 1,
+            [Define to 1 if you have KERN_PROCARGS and KERN_PROC_PATHNAME in <sys/sysctl.h>.])
+fi
+
+# Check for the clock_gettime function.
+AC_CHECK_FUNCS(clock_gettime)
+clock_gettime_link=
+# At least for glibc, clock_gettime is in librt.  But don't
+# pull that in if it still doesn't give us the function we want.  This
+# test is copied from libgomp, and modified to not link in -lrt as
+# we're using this for test timing only.
+if test "$ac_cv_func_clock_gettime" = no; then
+  AC_CHECK_LIB(rt, clock_gettime,
+    [CLOCK_GETTIME_LINK=-lrt
+     AC_DEFINE(HAVE_CLOCK_GETTIME, 1,
+	       [Define to 1 if you have the `clock_gettime' function.])])
+fi
+AC_SUBST(CLOCK_GETTIME_LINK)
+
+dnl Test whether the compiler supports the -pthread option.
+AC_CACHE_CHECK([whether -pthread is supported],
+[libgo_cv_lib_pthread],
+[CFLAGS_hold=$CFLAGS
+CFLAGS="$CFLAGS -pthread"
+AC_COMPILE_IFELSE([AC_LANG_SOURCE([int i;])],
+[libgo_cv_lib_pthread=yes],
+[libgo_cv_lib_pthread=no])
+CFLAGS=$CFLAGS_hold])
+PTHREAD_CFLAGS=
+if test "$libgo_cv_lib_pthread" = yes; then
+  PTHREAD_CFLAGS=-pthread
+fi
+AC_SUBST(PTHREAD_CFLAGS)
+
+AM_CONDITIONAL(HAVE_PTHREAD, test "$libgo_cv_lib_pthread" = yes)
+
+dnl Test whether the compiler and the linker support the -gdwarf-5 option.
+AC_CACHE_CHECK([whether -gdwarf-5 is supported],
+[libbacktrace_cv_lib_dwarf5],
+[CFLAGS_hold=$CFLAGS
+CFLAGS="$CFLAGS -gdwarf-5"
+AC_LINK_IFELSE([AC_LANG_PROGRAM([int i;], [return 0;])],
+[libbacktrace_cv_lib_dwarf5=yes],
+[libbacktrace_cv_lib_dwarf5=no])
+CFLAGS=$CFLAGS_hold])
+AM_CONDITIONAL(HAVE_DWARF5, test "$libbacktrace_cv_lib_dwarf5" = yes)
+
+AC_CHECK_LIB([z], [compress],
+    [AC_DEFINE(HAVE_ZLIB, 1, [Define if -lz is available.])])
+AM_CONDITIONAL(HAVE_ZLIB, test "$ac_cv_lib_z_compress" = yes)
+
+dnl Test whether the linker supports the --compress_debug_sections option.
+AC_CACHE_CHECK([whether --compress-debug-sections is supported],
+[libgo_cv_ld_compress],
+[LDFLAGS_hold=$LDFLAGS
+LDFLAGS="$LDFLAGS -Wl,--compress-debug-sections=zlib-gnu"
+AC_LINK_IFELSE([AC_LANG_PROGRAM(,)],
+[libgo_cv_ld_compress=yes],
+[libgo_cv_ld_compress=no])
+LDFLAGS=$LDFLAGS_hold])
+AM_CONDITIONAL(HAVE_COMPRESSED_DEBUG, test "$libgo_cv_ld_compress" = yes)
+
+AC_ARG_VAR(OBJCOPY, [location of objcopy])
+AC_CHECK_PROG(OBJCOPY, objcopy, objcopy,)
+AC_CHECK_PROG(READELF, readelf, readelf)
+AC_CACHE_CHECK([whether objcopy supports debuglink],
+[libbacktrace_cv_objcopy_debuglink],
+[if test -n "${with_target_subdir}"; then
+  libbacktrace_cv_objcopy_debuglink=no
+elif ! test -n "${OBJCOPY}"; then
+  libbacktrace_cv_objcopy_debuglink=no
+elif ${OBJCOPY} --help | fgrep add-gnu-debuglink >/dev/null 2>&1; then
+  libbacktrace_cv_objcopy_debuglink=yes
+else
+  libbacktrace_cv_objcopy_debuglink=no
+fi])
+AM_CONDITIONAL(HAVE_OBJCOPY_DEBUGLINK, test "$libbacktrace_cv_objcopy_debuglink" = yes)
+
+AC_ARG_VAR(DSYMUTIL, [location of dsymutil])
+AC_CHECK_PROG(DSYMUTIL, dsymutil, dsymutil)
+AM_CONDITIONAL(USE_DSYMUTIL, test -n "${DSYMUTIL}" -a "$FORMAT_FILE" = "macho.lo")
+
+AC_ARG_VAR(NM, [location of nm])
+AC_CHECK_PROG(NM, nm, nm)
+
+AC_CHECK_PROG(XZ, xz, xz)
+AM_CONDITIONAL(HAVE_XZ, test "$XZ" != "")
+AC_CHECK_PROG(COMM, comm, comm)
+AM_CONDITIONAL(HAVE_COMM, test "$COMM" != "")
+
+AM_CONDITIONAL(HAVE_MINIDEBUG,
+  test "${with_target_subdir}" = "" -a "$FORMAT_FILE" = "elf.lo" -a "${OBJCOPY}" != "" -a "${NM}" != "" -a "${XZ}" != "" -a "${COMM}" != "")
+
+AC_CHECK_LIB([lzma], [lzma_auto_decoder],
+    [AC_DEFINE(HAVE_LIBLZMA, 1, [Define if -llzma is available.])])
+AM_CONDITIONAL(HAVE_LIBLZMA, test "$ac_cv_lib_lzma_lzma_auto_decoder" = yes)
+
+AC_CACHE_CHECK([whether tests can run],
+  [libbacktrace_cv_sys_native],
+  [AC_RUN_IFELSE([AC_LANG_PROGRAM([], [return 0;])],
+     [libbacktrace_cv_sys_native=yes],
+     [libbacktrace_cv_sys_native=no],
+     [libbacktrace_cv_sys_native=no])])
+AM_CONDITIONAL(NATIVE, test "$libbacktrace_cv_sys_native" = "yes")
+
+if test "${multilib}" = "yes"; then
+  multilib_arg="--enable-multilib"
+else
+  multilib_arg=
+fi
+
+AC_CONFIG_FILES(Makefile backtrace-supported.h)
+AC_CONFIG_FILES(install-debuginfo-for-buildid.sh, chmod +x install-debuginfo-for-buildid.sh)
+
+# We need multilib support, but only if configuring for the target.
+AC_CONFIG_COMMANDS([default],
+[if test -n "$CONFIG_FILES"; then
+   if test -n "${with_target_subdir}"; then
+     # Multilibs need MULTISUBDIR defined correctly in certain makefiles so
+     # that multilib installs will end up installed in the correct place.
+     # The testsuite needs it for multilib-aware ABI baseline files.
+     # To work around this not being passed down from config-ml.in ->
+     # srcdir/Makefile.am -> srcdir/{src,libsupc++,...}/Makefile.am, manually
+     # append it here.  Only modify Makefiles that have just been created.
+     #
+     # Also, get rid of this simulated-VPATH thing that automake does.
+     cat > vpsed << \_EOF
+  s!`test -f '$<' || echo '$(srcdir)/'`!!
+_EOF
+     for i in $SUBDIRS; do
+      case $CONFIG_FILES in
+       *${i}/Makefile*)
+	 #echo "Adding MULTISUBDIR to $i/Makefile"
+	 sed -f vpsed $i/Makefile > tmp
+	 grep '^MULTISUBDIR =' Makefile >> tmp
+	 mv tmp $i/Makefile
+	 ;;
+      esac
+     done
+     rm vpsed
+   fi
+ fi
+],
+[
+# Variables needed in config.status (file generation) which aren't already
+# passed by autoconf.
+SUBDIRS="$SUBDIRS"
+])
+
+AC_OUTPUT

libbacktrace/edtest.c

@@ -0,0 +1,120 @@
+/* edtest.c -- Test for libbacktrace storage allocation stress handling
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+#include "internal.h"
+
+#include "testlib.h"
+
+static int test1 (void) __attribute__ ((noinline, noclone, unused));
+extern int f2 (int);
+extern int f3 (int, int);
+
+static int
+test1 (void)
+{
+  /* Returning a value here and elsewhere avoids a tailcall which
+     would mess up the backtrace.  */
+  return f2 (__LINE__) + 1;
+}
+
+int
+f3 (int f1line, int f2line)
+{
+  struct info all[20];
+  struct bdata data;
+  int f3line;
+  int i;
+
+  data.all = &all[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_full (state, 0, callback_one, error_callback_one, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test1: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (data.index < 3)
+    {
+      fprintf (stderr,
+               "test1: not enough frames; got %zu, expected at least 3\n",
+               data.index);
+      data.failed = 1;
+    }
+
+  check ("test1", 0, all, f3line, "f3", "edtest.c", &data.failed);
+  check ("test1", 1, all, f2line, "f2", "edtest2_build.c", &data.failed);
+  check ("test1", 2, all, f1line, "test1", "edtest.c", &data.failed);
+
+  printf ("%s: backtrace_full alloc stress\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED)
+{
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+                                  error_callback_create, NULL);
+
+  // Grab the storage allocation lock prior to doing anything interesting.
+  // The intent here is to insure that the backtrace_alloc code is forced
+  // to always call mmap() for new memory as opposed to reusing previously
+  // allocated memory from the free list. Doing things this way helps
+  // simulate what you might see in a multithreaded program in which there
+  // are racing calls to the allocator.
+  struct backtrace_state *state_internal =
+      (struct backtrace_state *) state;
+  state_internal->lock_alloc = 1;
+
+  // Kick off the test
+  test1();
+
+  exit (failures > 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/edtest2.c

@@ -0,0 +1,43 @@
+/* edtest2.c -- Test for libbacktrace storage allocation stress handling (p2)
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* This file intentionally written without any #include's
+ */
+
+extern int f3(int, int);
+extern int f2(int);
+
+int f2(int x)
+{
+  /* Returning a value here and elsewhere avoids a tailcall which
+     would mess up the backtrace.  */
+  return f3(x, __LINE__) + 3;
+}

libbacktrace/fileline.c

@@ -0,0 +1,346 @@
+/* fileline.c -- Get file and line number information in a backtrace.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#if defined (HAVE_KERN_PROC_ARGS) || defined (HAVE_KERN_PROC)
+#include <sys/sysctl.h>
+#endif
+
+#ifdef HAVE_MACH_O_DYLD_H
+#include <mach-o/dyld.h>
+#endif
+
+#include "backtrace.h"
+#include "internal.h"
+
+#ifndef HAVE_GETEXECNAME
+#define getexecname() NULL
+#endif
+
+#if !defined (HAVE_KERN_PROC_ARGS) && !defined (HAVE_KERN_PROC)
+
+#define sysctl_exec_name1(state, error_callback, data) NULL
+#define sysctl_exec_name2(state, error_callback, data) NULL
+
+#else /* defined (HAVE_KERN_PROC_ARGS) || |defined (HAVE_KERN_PROC) */
+
+static char *
+sysctl_exec_name (struct backtrace_state *state,
+		  int mib0, int mib1, int mib2, int mib3,
+		  backtrace_error_callback error_callback, void *data)
+{
+  int mib[4];
+  size_t len;
+  char *name;
+  size_t rlen;
+
+  mib[0] = mib0;
+  mib[1] = mib1;
+  mib[2] = mib2;
+  mib[3] = mib3;
+
+  if (sysctl (mib, 4, NULL, &len, NULL, 0) < 0)
+    return NULL;
+  name = (char *) backtrace_alloc (state, len, error_callback, data);
+  if (name == NULL)
+    return NULL;
+  rlen = len;
+  if (sysctl (mib, 4, name, &rlen, NULL, 0) < 0)
+    {
+      backtrace_free (state, name, len, error_callback, data);
+      return NULL;
+    }
+  return name;
+}
+
+#ifdef HAVE_KERN_PROC_ARGS
+
+static char *
+sysctl_exec_name1 (struct backtrace_state *state,
+		   backtrace_error_callback error_callback, void *data)
+{
+  /* This variant is used on NetBSD.  */
+  return sysctl_exec_name (state, CTL_KERN, KERN_PROC_ARGS, -1,
+			   KERN_PROC_PATHNAME, error_callback, data);
+}
+
+#else
+
+#define sysctl_exec_name1(state, error_callback, data) NULL
+
+#endif
+
+#ifdef HAVE_KERN_PROC
+
+static char *
+sysctl_exec_name2 (struct backtrace_state *state,
+		   backtrace_error_callback error_callback, void *data)
+{
+  /* This variant is used on FreeBSD.  */
+  return sysctl_exec_name (state, CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1,
+			   error_callback, data);
+}
+
+#else
+
+#define sysctl_exec_name2(state, error_callback, data) NULL
+
+#endif
+
+#endif /* defined (HAVE_KERN_PROC_ARGS) || |defined (HAVE_KERN_PROC) */
+
+#ifdef HAVE_MACH_O_DYLD_H
+
+static char *
+macho_get_executable_path (struct backtrace_state *state,
+			   backtrace_error_callback error_callback, void *data)
+{
+  uint32_t len;
+  char *name;
+
+  len = 0;
+  if (_NSGetExecutablePath (NULL, &len) == 0)
+    return NULL;
+  name = (char *) backtrace_alloc (state, len, error_callback, data);
+  if (name == NULL)
+    return NULL;
+  if (_NSGetExecutablePath (name, &len) != 0)
+    {
+      backtrace_free (state, name, len, error_callback, data);
+      return NULL;
+    }
+  return name;
+}
+
+#else /* !defined (HAVE_MACH_O_DYLD_H) */
+
+#define macho_get_executable_path(state, error_callback, data) NULL
+
+#endif /* !defined (HAVE_MACH_O_DYLD_H) */
+
+/* Initialize the fileline information from the executable.  Returns 1
+   on success, 0 on failure.  */
+
+static int
+fileline_initialize (struct backtrace_state *state,
+		     backtrace_error_callback error_callback, void *data)
+{
+  int failed;
+  fileline fileline_fn;
+  int pass;
+  int called_error_callback;
+  int descriptor;
+  const char *filename;
+  char buf[64];
+
+  if (!state->threaded)
+    failed = state->fileline_initialization_failed;
+  else
+    failed = backtrace_atomic_load_int (&state->fileline_initialization_failed);
+
+  if (failed)
+    {
+      error_callback (data, "failed to read executable information", -1);
+      return 0;
+    }
+
+  if (!state->threaded)
+    fileline_fn = state->fileline_fn;
+  else
+    fileline_fn = backtrace_atomic_load_pointer (&state->fileline_fn);
+  if (fileline_fn != NULL)
+    return 1;
+
+  /* We have not initialized the information.  Do it now.  */
+
+  descriptor = -1;
+  called_error_callback = 0;
+  for (pass = 0; pass < 8; ++pass)
+    {
+      int does_not_exist;
+
+      switch (pass)
+	{
+	case 0:
+	  filename = state->filename;
+	  break;
+	case 1:
+	  filename = getexecname ();
+	  break;
+	case 2:
+	  filename = "/proc/self/exe";
+	  break;
+	case 3:
+	  filename = "/proc/curproc/file";
+	  break;
+	case 4:
+	  snprintf (buf, sizeof (buf), "/proc/%ld/object/a.out",
+		    (long) getpid ());
+	  filename = buf;
+	  break;
+	case 5:
+	  filename = sysctl_exec_name1 (state, error_callback, data);
+	  break;
+	case 6:
+	  filename = sysctl_exec_name2 (state, error_callback, data);
+	  break;
+	case 7:
+	  filename = macho_get_executable_path (state, error_callback, data);
+	  break;
+	default:
+	  abort ();
+	}
+
+      if (filename == NULL)
+	continue;
+
+      descriptor = backtrace_open (filename, error_callback, data,
+				   &does_not_exist);
+      if (descriptor < 0 && !does_not_exist)
+	{
+	  called_error_callback = 1;
+	  break;
+	}
+      if (descriptor >= 0)
+	break;
+    }
+
+  if (descriptor < 0)
+    {
+      if (!called_error_callback)
+	{
+	  if (state->filename != NULL)
+	    error_callback (data, state->filename, ENOENT);
+	  else
+	    error_callback (data,
+			    "libbacktrace could not find executable to open",
+			    0);
+	}
+      failed = 1;
+    }
+
+  if (!failed)
+    {
+      if (!backtrace_initialize (state, filename, descriptor, error_callback,
+				 data, &fileline_fn))
+	failed = 1;
+    }
+
+  if (failed)
+    {
+      if (!state->threaded)
+	state->fileline_initialization_failed = 1;
+      else
+	backtrace_atomic_store_int (&state->fileline_initialization_failed, 1);
+      return 0;
+    }
+
+  if (!state->threaded)
+    state->fileline_fn = fileline_fn;
+  else
+    {
+      backtrace_atomic_store_pointer (&state->fileline_fn, fileline_fn);
+
+      /* Note that if two threads initialize at once, one of the data
+	 sets may be leaked.  */
+    }
+
+  return 1;
+}
+
+/* Given a PC, find the file name, line number, and function name.  */
+
+int
+backtrace_pcinfo (struct backtrace_state *state, uintptr_t pc,
+		  backtrace_full_callback callback,
+		  backtrace_error_callback error_callback, void *data)
+{
+  if (!fileline_initialize (state, error_callback, data))
+    return 0;
+
+  if (state->fileline_initialization_failed)
+    return 0;
+
+  return state->fileline_fn (state, pc, callback, error_callback, data);
+}
+
+/* Given a PC, find the symbol for it, and its value.  */
+
+int
+backtrace_syminfo (struct backtrace_state *state, uintptr_t pc,
+		   backtrace_syminfo_callback callback,
+		   backtrace_error_callback error_callback, void *data)
+{
+  if (!fileline_initialize (state, error_callback, data))
+    return 0;
+
+  if (state->fileline_initialization_failed)
+    return 0;
+
+  state->syminfo_fn (state, pc, callback, error_callback, data);
+  return 1;
+}
+
+/* A backtrace_syminfo_callback that can call into a
+   backtrace_full_callback, used when we have a symbol table but no
+   debug info.  */
+
+void
+backtrace_syminfo_to_full_callback (void *data, uintptr_t pc,
+				    const char *symname,
+				    uintptr_t symval ATTRIBUTE_UNUSED,
+				    uintptr_t symsize ATTRIBUTE_UNUSED)
+{
+  struct backtrace_call_full *bdata = (struct backtrace_call_full *) data;
+
+  bdata->ret = bdata->full_callback (bdata->full_data, pc, NULL, 0, symname);
+}
+
+/* An error callback that corresponds to
+   backtrace_syminfo_to_full_callback.  */
+
+void
+backtrace_syminfo_to_full_error_callback (void *data, const char *msg,
+					  int errnum)
+{
+  struct backtrace_call_full *bdata = (struct backtrace_call_full *) data;
+
+  bdata->full_error_callback (bdata->full_data, msg, errnum);
+}

libbacktrace/filetype.awk

@@ -0,0 +1,13 @@
+# An awk script to determine the type of a file.
+/^\177ELF\001/      { if (NR == 1) { print "elf32"; exit } }
+/^\177ELF\002/      { if (NR == 1) { print "elf64"; exit } }
+/^\114\001/         { if (NR == 1) { print "pecoff"; exit } }
+/^\144\206/         { if (NR == 1) { print "pecoff"; exit } }
+/^\001\337/         { if (NR == 1) { print "xcoff32"; exit } }
+/^\001\367/         { if (NR == 1) { print "xcoff64"; exit } }
+/^\376\355\372\316/ { if (NR == 1) { print "macho"; exit } }
+/^\316\372\355\376/ { if (NR == 1) { print "macho"; exit } }
+/^\376\355\372\317/ { if (NR == 1) { print "macho"; exit } }
+/^\317\372\355\376/ { if (NR == 1) { print "macho"; exit } }
+/^\312\376\272\276/ { if (NR == 1) { print "macho"; exit } }
+/^\276\272\376\312/ { if (NR == 1) { print "macho"; exit } }

libbacktrace/install-debuginfo-for-buildid.sh.in

@@ -0,0 +1,65 @@
+#!/bin/sh
+
+# install-debug-info-for-buildid.sh -- Helper script for libbacktrace library
+# testing.
+# Copyright (C) 2019-2021 Free Software Foundation, Inc.
+
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+
+#     (1) Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+
+#     (2) Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+
+#     (3) The name of the author may not be used to
+#     endorse or promote products derived from this software without
+#     specific prior written permission.
+
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+# INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+# STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+# IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+# Extract build-id from src, and copy debug info of src to
+# $build_id_dir/aa/bb...zz.debug.
+
+set -e
+
+sed=@SED@
+awk=@AWK@
+grep=@GREP@
+objcopy=@OBJCOPY@
+readelf=@READELF@
+mkdir_p="@MKDIR_P@"
+
+build_id_dir="$1"
+src="$2"
+
+buildid=$(LANG=C $readelf -n $src \
+	      | $grep "Build ID" \
+	      | $awk '{print $3}')
+
+prefix=$(echo $buildid \
+	     | $sed 's/^\(.\{2\}\).*/\1/')
+
+remainder=$(echo $buildid \
+		| $sed 's/^.\{2\}//')
+
+dir=$build_id_dir/$prefix
+dst=$dir/$remainder.debug
+
+$mkdir_p $dir
+
+$objcopy --only-keep-debug $src $dst

libbacktrace/instrumented_alloc.c

@@ -0,0 +1,114 @@
+/* instrumented_alloc.c -- Memory allocation instrumented to fail when
+   requested, for testing purposes.
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* Include all the header files of alloc here, to make sure they're not
+   processed when including alloc.c below, such that the redefinitions of malloc
+   and realloc are only effective in alloc.c itself.  This does not work for
+   config.h, because it's not wrapped in "#ifndef CONFIG_H\n#define CONFIG_H"
+   and "#endif" but that does not seem to be harmful.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <inttypes.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+extern void *instrumented_malloc (size_t size);
+extern void *instrumented_realloc (void *ptr, size_t size);
+
+#define malloc instrumented_malloc
+#define realloc instrumented_realloc
+#include "alloc.c"
+#undef malloc
+#undef realloc
+
+static uint64_t nr_allocs = 0;
+static uint64_t fail_at_alloc = 0;
+
+extern int at_fail_alloc_p (void);
+extern uint64_t get_nr_allocs (void);
+extern void set_fail_at_alloc (uint64_t);
+
+void *
+instrumented_malloc (size_t size)
+{
+  void *res;
+
+  if (at_fail_alloc_p ())
+    return NULL;
+
+  res = malloc (size);
+  if (res != NULL)
+    nr_allocs++;
+
+  return res;
+}
+
+void *
+instrumented_realloc (void *ptr, size_t size)
+{
+  void *res;
+
+  if (size != 0)
+    {
+      if (at_fail_alloc_p ())
+	return NULL;
+    }
+
+  res = realloc (ptr, size);
+  if (res != NULL)
+    nr_allocs++;
+
+  return res;
+}
+
+int
+at_fail_alloc_p (void)
+{
+  return fail_at_alloc == nr_allocs + 1;
+}
+
+uint64_t
+get_nr_allocs (void)
+{
+  return nr_allocs;
+}
+
+void
+set_fail_at_alloc (uint64_t nr)
+{
+  fail_at_alloc = nr;
+}

libbacktrace/internal.h

@@ -0,0 +1,380 @@
+/* internal.h -- Internal header file for stack backtrace library.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#ifndef BACKTRACE_INTERNAL_H
+#define BACKTRACE_INTERNAL_H
+
+/* We assume that <sys/types.h> and "backtrace.h" have already been
+   included.  */
+
+#ifndef GCC_VERSION
+# define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
+#endif
+
+#if (GCC_VERSION < 2007)
+# define __attribute__(x)
+#endif
+
+#ifndef ATTRIBUTE_UNUSED
+# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+#endif
+
+#ifndef ATTRIBUTE_MALLOC
+# if (GCC_VERSION >= 2096)
+#  define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
+# else
+#  define ATTRIBUTE_MALLOC
+# endif
+#endif
+
+#ifndef ATTRIBUTE_FALLTHROUGH
+# if (GCC_VERSION >= 7000)
+#  define ATTRIBUTE_FALLTHROUGH __attribute__ ((__fallthrough__))
+# else
+#  define ATTRIBUTE_FALLTHROUGH
+# endif
+#endif
+
+#ifndef HAVE_SYNC_FUNCTIONS
+
+/* Define out the sync functions.  These should never be called if
+   they are not available.  */
+
+#define __sync_bool_compare_and_swap(A, B, C) (abort(), 1)
+#define __sync_lock_test_and_set(A, B) (abort(), 0)
+#define __sync_lock_release(A) abort()
+
+#endif /* !defined (HAVE_SYNC_FUNCTIONS) */
+
+#ifdef HAVE_ATOMIC_FUNCTIONS
+
+/* We have the atomic builtin functions.  */
+
+#define backtrace_atomic_load_pointer(p) \
+    __atomic_load_n ((p), __ATOMIC_ACQUIRE)
+#define backtrace_atomic_load_int(p) \
+    __atomic_load_n ((p), __ATOMIC_ACQUIRE)
+#define backtrace_atomic_store_pointer(p, v) \
+    __atomic_store_n ((p), (v), __ATOMIC_RELEASE)
+#define backtrace_atomic_store_size_t(p, v) \
+    __atomic_store_n ((p), (v), __ATOMIC_RELEASE)
+#define backtrace_atomic_store_int(p, v) \
+    __atomic_store_n ((p), (v), __ATOMIC_RELEASE)
+
+#else /* !defined (HAVE_ATOMIC_FUNCTIONS) */
+#ifdef HAVE_SYNC_FUNCTIONS
+
+/* We have the sync functions but not the atomic functions.  Define
+   the atomic ones in terms of the sync ones.  */
+
+extern void *backtrace_atomic_load_pointer (void *);
+extern int backtrace_atomic_load_int (int *);
+extern void backtrace_atomic_store_pointer (void *, void *);
+extern void backtrace_atomic_store_size_t (size_t *, size_t);
+extern void backtrace_atomic_store_int (int *, int);
+
+#else /* !defined (HAVE_SYNC_FUNCTIONS) */
+
+/* We have neither the sync nor the atomic functions.  These will
+   never be called.  */
+
+#define backtrace_atomic_load_pointer(p) (abort(), (void *) NULL)
+#define backtrace_atomic_load_int(p) (abort(), 0)
+#define backtrace_atomic_store_pointer(p, v) abort()
+#define backtrace_atomic_store_size_t(p, v) abort()
+#define backtrace_atomic_store_int(p, v) abort()
+
+#endif /* !defined (HAVE_SYNC_FUNCTIONS) */
+#endif /* !defined (HAVE_ATOMIC_FUNCTIONS) */
+
+/* The type of the function that collects file/line information.  This
+   is like backtrace_pcinfo.  */
+
+typedef int (*fileline) (struct backtrace_state *state, uintptr_t pc,
+			 backtrace_full_callback callback,
+			 backtrace_error_callback error_callback, void *data);
+
+/* The type of the function that collects symbol information.  This is
+   like backtrace_syminfo.  */
+
+typedef void (*syminfo) (struct backtrace_state *state, uintptr_t pc,
+			 backtrace_syminfo_callback callback,
+			 backtrace_error_callback error_callback, void *data);
+
+/* What the backtrace state pointer points to.  */
+
+struct backtrace_state
+{
+  /* The name of the executable.  */
+  const char *filename;
+  /* Non-zero if threaded.  */
+  int threaded;
+  /* The master lock for fileline_fn, fileline_data, syminfo_fn,
+     syminfo_data, fileline_initialization_failed and everything the
+     data pointers point to.  */
+  void *lock;
+  /* The function that returns file/line information.  */
+  fileline fileline_fn;
+  /* The data to pass to FILELINE_FN.  */
+  void *fileline_data;
+  /* The function that returns symbol information.  */
+  syminfo syminfo_fn;
+  /* The data to pass to SYMINFO_FN.  */
+  void *syminfo_data;
+  /* Whether initializing the file/line information failed.  */
+  int fileline_initialization_failed;
+  /* The lock for the freelist.  */
+  int lock_alloc;
+  /* The freelist when using mmap.  */
+  struct backtrace_freelist_struct *freelist;
+};
+
+/* Open a file for reading.  Returns -1 on error.  If DOES_NOT_EXIST
+   is not NULL, *DOES_NOT_EXIST will be set to 0 normally and set to 1
+   if the file does not exist.  If the file does not exist and
+   DOES_NOT_EXIST is not NULL, the function will return -1 and will
+   not call ERROR_CALLBACK.  On other errors, or if DOES_NOT_EXIST is
+   NULL, the function will call ERROR_CALLBACK before returning.  */
+extern int backtrace_open (const char *filename,
+			   backtrace_error_callback error_callback,
+			   void *data,
+			   int *does_not_exist);
+
+/* A view of the contents of a file.  This supports mmap when
+   available.  A view will remain in memory even after backtrace_close
+   is called on the file descriptor from which the view was
+   obtained.  */
+
+struct backtrace_view
+{
+  /* The data that the caller requested.  */
+  const void *data;
+  /* The base of the view.  */
+  void *base;
+  /* The total length of the view.  */
+  size_t len;
+};
+
+/* Create a view of SIZE bytes from DESCRIPTOR at OFFSET.  Store the
+   result in *VIEW.  Returns 1 on success, 0 on error.  */
+extern int backtrace_get_view (struct backtrace_state *state, int descriptor,
+			       off_t offset, uint64_t size,
+			       backtrace_error_callback error_callback,
+			       void *data, struct backtrace_view *view);
+
+/* Release a view created by backtrace_get_view.  */
+extern void backtrace_release_view (struct backtrace_state *state,
+				    struct backtrace_view *view,
+				    backtrace_error_callback error_callback,
+				    void *data);
+
+/* Close a file opened by backtrace_open.  Returns 1 on success, 0 on
+   error.  */
+
+extern int backtrace_close (int descriptor,
+			    backtrace_error_callback error_callback,
+			    void *data);
+
+/* Sort without using memory.  */
+
+extern void backtrace_qsort (void *base, size_t count, size_t size,
+			     int (*compar) (const void *, const void *));
+
+/* Allocate memory.  This is like malloc.  If ERROR_CALLBACK is NULL,
+   this does not report an error, it just returns NULL.  */
+
+extern void *backtrace_alloc (struct backtrace_state *state, size_t size,
+			      backtrace_error_callback error_callback,
+			      void *data) ATTRIBUTE_MALLOC;
+
+/* Free memory allocated by backtrace_alloc.  If ERROR_CALLBACK is
+   NULL, this does not report an error.  */
+
+extern void backtrace_free (struct backtrace_state *state, void *mem,
+			    size_t size,
+			    backtrace_error_callback error_callback,
+			    void *data);
+
+/* A growable vector of some struct.  This is used for more efficient
+   allocation when we don't know the final size of some group of data
+   that we want to represent as an array.  */
+
+struct backtrace_vector
+{
+  /* The base of the vector.  */
+  void *base;
+  /* The number of bytes in the vector.  */
+  size_t size;
+  /* The number of bytes available at the current allocation.  */
+  size_t alc;
+};
+
+/* Grow VEC by SIZE bytes.  Return a pointer to the newly allocated
+   bytes.  Note that this may move the entire vector to a new memory
+   location.  Returns NULL on failure.  */
+
+extern void *backtrace_vector_grow (struct backtrace_state *state, size_t size,
+				    backtrace_error_callback error_callback,
+				    void *data,
+				    struct backtrace_vector *vec);
+
+/* Finish the current allocation on VEC.  Prepare to start a new
+   allocation.  The finished allocation will never be freed.  Returns
+   a pointer to the base of the finished entries, or NULL on
+   failure.  */
+
+extern void* backtrace_vector_finish (struct backtrace_state *state,
+				      struct backtrace_vector *vec,
+				      backtrace_error_callback error_callback,
+				      void *data);
+
+/* Release any extra space allocated for VEC.  This may change
+   VEC->base.  Returns 1 on success, 0 on failure.  */
+
+extern int backtrace_vector_release (struct backtrace_state *state,
+				     struct backtrace_vector *vec,
+				     backtrace_error_callback error_callback,
+				     void *data);
+
+/* Free the space managed by VEC.  This will reset VEC.  */
+
+static inline void
+backtrace_vector_free (struct backtrace_state *state,
+		       struct backtrace_vector *vec,
+		       backtrace_error_callback error_callback, void *data)
+{
+  vec->alc += vec->size;
+  vec->size = 0;
+  backtrace_vector_release (state, vec, error_callback, data);
+}
+
+/* Read initial debug data from a descriptor, and set the
+   fileline_data, syminfo_fn, and syminfo_data fields of STATE.
+   Return the fileln_fn field in *FILELN_FN--this is done this way so
+   that the synchronization code is only implemented once.  This is
+   called after the descriptor has first been opened.  It will close
+   the descriptor if it is no longer needed.  Returns 1 on success, 0
+   on error.  There will be multiple implementations of this function,
+   for different file formats.  Each system will compile the
+   appropriate one.  */
+
+extern int backtrace_initialize (struct backtrace_state *state,
+				 const char *filename,
+				 int descriptor,
+				 backtrace_error_callback error_callback,
+				 void *data,
+				 fileline *fileline_fn);
+
+/* An enum for the DWARF sections we care about.  */
+
+enum dwarf_section
+{
+  DEBUG_INFO,
+  DEBUG_LINE,
+  DEBUG_ABBREV,
+  DEBUG_RANGES,
+  DEBUG_STR,
+  DEBUG_ADDR,
+  DEBUG_STR_OFFSETS,
+  DEBUG_LINE_STR,
+  DEBUG_RNGLISTS,
+
+  DEBUG_MAX
+};
+
+/* Data for the DWARF sections we care about.  */
+
+struct dwarf_sections
+{
+  const unsigned char *data[DEBUG_MAX];
+  size_t size[DEBUG_MAX];
+};
+
+/* DWARF data read from a file, used for .gnu_debugaltlink.  */
+
+struct dwarf_data;
+
+/* Add file/line information for a DWARF module.  */
+
+extern int backtrace_dwarf_add (struct backtrace_state *state,
+				uintptr_t base_address,
+				const struct dwarf_sections *dwarf_sections,
+				int is_bigendian,
+				struct dwarf_data *fileline_altlink,
+				backtrace_error_callback error_callback,
+				void *data, fileline *fileline_fn,
+				struct dwarf_data **fileline_entry);
+
+/* A data structure to pass to backtrace_syminfo_to_full.  */
+
+struct backtrace_call_full
+{
+  backtrace_full_callback full_callback;
+  backtrace_error_callback full_error_callback;
+  void *full_data;
+  int ret;
+};
+
+/* A backtrace_syminfo_callback that can call into a
+   backtrace_full_callback, used when we have a symbol table but no
+   debug info.  */
+
+extern void backtrace_syminfo_to_full_callback (void *data, uintptr_t pc,
+						const char *symname,
+						uintptr_t symval,
+						uintptr_t symsize);
+
+/* An error callback that corresponds to
+   backtrace_syminfo_to_full_callback.  */
+
+extern void backtrace_syminfo_to_full_error_callback (void *, const char *,
+						      int);
+
+/* A test-only hook for elf_uncompress_zdebug.  */
+
+extern int backtrace_uncompress_zdebug (struct backtrace_state *,
+					const unsigned char *compressed,
+					size_t compressed_size,
+					backtrace_error_callback, void *data,
+					unsigned char **uncompressed,
+					size_t *uncompressed_size);
+
+/* A test-only hook for elf_uncompress_lzma.  */
+
+extern int backtrace_uncompress_lzma (struct backtrace_state *,
+				      const unsigned char *compressed,
+				      size_t compressed_size,
+				      backtrace_error_callback, void *data,
+				      unsigned char **uncompressed,
+				      size_t *uncompressed_size);
+
+#endif

libbacktrace/mmap.c

@@ -0,0 +1,331 @@
+/* mmap.c -- Memory allocation with mmap.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+#ifndef HAVE_DECL_GETPAGESIZE
+extern int getpagesize (void);
+#endif
+
+/* Memory allocation on systems that provide anonymous mmap.  This
+   permits the backtrace functions to be invoked from a signal
+   handler, assuming that mmap is async-signal safe.  */
+
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
+#ifndef MAP_FAILED
+#define MAP_FAILED ((void *)-1)
+#endif
+
+/* A list of free memory blocks.  */
+
+struct backtrace_freelist_struct
+{
+  /* Next on list.  */
+  struct backtrace_freelist_struct *next;
+  /* Size of this block, including this structure.  */
+  size_t size;
+};
+
+/* Free memory allocated by backtrace_alloc.  */
+
+static void
+backtrace_free_locked (struct backtrace_state *state, void *addr, size_t size)
+{
+  /* Just leak small blocks.  We don't have to be perfect.  Don't put
+     more than 16 entries on the free list, to avoid wasting time
+     searching when allocating a block.  If we have more than 16
+     entries, leak the smallest entry.  */
+
+  if (size >= sizeof (struct backtrace_freelist_struct))
+    {
+      size_t c;
+      struct backtrace_freelist_struct **ppsmall;
+      struct backtrace_freelist_struct **pp;
+      struct backtrace_freelist_struct *p;
+
+      c = 0;
+      ppsmall = NULL;
+      for (pp = &state->freelist; *pp != NULL; pp = &(*pp)->next)
+	{
+	  if (ppsmall == NULL || (*pp)->size < (*ppsmall)->size)
+	    ppsmall = pp;
+	  ++c;
+	}
+      if (c >= 16)
+	{
+	  if (size <= (*ppsmall)->size)
+	    return;
+	  *ppsmall = (*ppsmall)->next;
+	}
+
+      p = (struct backtrace_freelist_struct *) addr;
+      p->next = state->freelist;
+      p->size = size;
+      state->freelist = p;
+    }
+}
+
+/* Allocate memory like malloc.  If ERROR_CALLBACK is NULL, don't
+   report an error.  */
+
+void *
+backtrace_alloc (struct backtrace_state *state,
+		 size_t size, backtrace_error_callback error_callback,
+		 void *data)
+{
+  void *ret;
+  int locked;
+  struct backtrace_freelist_struct **pp;
+  size_t pagesize;
+  size_t asksize;
+  void *page;
+
+  ret = NULL;
+
+  /* If we can acquire the lock, then see if there is space on the
+     free list.  If we can't acquire the lock, drop straight into
+     using mmap.  __sync_lock_test_and_set returns the old state of
+     the lock, so we have acquired it if it returns 0.  */
+
+  if (!state->threaded)
+    locked = 1;
+  else
+    locked = __sync_lock_test_and_set (&state->lock_alloc, 1) == 0;
+
+  if (locked)
+    {
+      for (pp = &state->freelist; *pp != NULL; pp = &(*pp)->next)
+	{
+	  if ((*pp)->size >= size)
+	    {
+	      struct backtrace_freelist_struct *p;
+
+	      p = *pp;
+	      *pp = p->next;
+
+	      /* Round for alignment; we assume that no type we care about
+		 is more than 8 bytes.  */
+	      size = (size + 7) & ~ (size_t) 7;
+	      if (size < p->size)
+		backtrace_free_locked (state, (char *) p + size,
+				       p->size - size);
+
+	      ret = (void *) p;
+
+	      break;
+	    }
+	}
+
+      if (state->threaded)
+	__sync_lock_release (&state->lock_alloc);
+    }
+
+  if (ret == NULL)
+    {
+      /* Allocate a new page.  */
+
+      pagesize = getpagesize ();
+      asksize = (size + pagesize - 1) & ~ (pagesize - 1);
+      page = mmap (NULL, asksize, PROT_READ | PROT_WRITE,
+		   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+      if (page == MAP_FAILED)
+	{
+	  if (error_callback)
+	    error_callback (data, "mmap", errno);
+	}
+      else
+	{
+	  size = (size + 7) & ~ (size_t) 7;
+	  if (size < asksize)
+	    backtrace_free (state, (char *) page + size, asksize - size,
+			    error_callback, data);
+
+	  ret = page;
+	}
+    }
+
+  return ret;
+}
+
+/* Free memory allocated by backtrace_alloc.  */
+
+void
+backtrace_free (struct backtrace_state *state, void *addr, size_t size,
+		backtrace_error_callback error_callback ATTRIBUTE_UNUSED,
+		void *data ATTRIBUTE_UNUSED)
+{
+  int locked;
+
+  /* If we are freeing a large aligned block, just release it back to
+     the system.  This case arises when growing a vector for a large
+     binary with lots of debug info.  Calling munmap here may cause us
+     to call mmap again if there is also a large shared library; we
+     just live with that.  */
+  if (size >= 16 * 4096)
+    {
+      size_t pagesize;
+
+      pagesize = getpagesize ();
+      if (((uintptr_t) addr & (pagesize - 1)) == 0
+	  && (size & (pagesize - 1)) == 0)
+	{
+	  /* If munmap fails for some reason, just add the block to
+	     the freelist.  */
+	  if (munmap (addr, size) == 0)
+	    return;
+	}
+    }
+
+  /* If we can acquire the lock, add the new space to the free list.
+     If we can't acquire the lock, just leak the memory.
+     __sync_lock_test_and_set returns the old state of the lock, so we
+     have acquired it if it returns 0.  */
+
+  if (!state->threaded)
+    locked = 1;
+  else
+    locked = __sync_lock_test_and_set (&state->lock_alloc, 1) == 0;
+
+  if (locked)
+    {
+      backtrace_free_locked (state, addr, size);
+
+      if (state->threaded)
+	__sync_lock_release (&state->lock_alloc);
+    }
+}
+
+/* Grow VEC by SIZE bytes.  */
+
+void *
+backtrace_vector_grow (struct backtrace_state *state,size_t size,
+		       backtrace_error_callback error_callback,
+		       void *data, struct backtrace_vector *vec)
+{
+  void *ret;
+
+  if (size > vec->alc)
+    {
+      size_t pagesize;
+      size_t alc;
+      void *base;
+
+      pagesize = getpagesize ();
+      alc = vec->size + size;
+      if (vec->size == 0)
+	alc = 16 * size;
+      else if (alc < pagesize)
+	{
+	  alc *= 2;
+	  if (alc > pagesize)
+	    alc = pagesize;
+	}
+      else
+	{
+	  alc *= 2;
+	  alc = (alc + pagesize - 1) & ~ (pagesize - 1);
+	}
+      base = backtrace_alloc (state, alc, error_callback, data);
+      if (base == NULL)
+	return NULL;
+      if (vec->base != NULL)
+	{
+	  memcpy (base, vec->base, vec->size);
+	  backtrace_free (state, vec->base, vec->size + vec->alc,
+			  error_callback, data);
+	}
+      vec->base = base;
+      vec->alc = alc - vec->size;
+    }
+
+  ret = (char *) vec->base + vec->size;
+  vec->size += size;
+  vec->alc -= size;
+  return ret;
+}
+
+/* Finish the current allocation on VEC.  */
+
+void *
+backtrace_vector_finish (
+  struct backtrace_state *state ATTRIBUTE_UNUSED,
+  struct backtrace_vector *vec,
+  backtrace_error_callback error_callback ATTRIBUTE_UNUSED,
+  void *data ATTRIBUTE_UNUSED)
+{
+  void *ret;
+
+  ret = vec->base;
+  vec->base = (char *) vec->base + vec->size;
+  vec->size = 0;
+  return ret;
+}
+
+/* Release any extra space allocated for VEC.  */
+
+int
+backtrace_vector_release (struct backtrace_state *state,
+			  struct backtrace_vector *vec,
+			  backtrace_error_callback error_callback,
+			  void *data)
+{
+  size_t size;
+  size_t alc;
+  size_t aligned;
+
+  /* Make sure that the block that we free is aligned on an 8-byte
+     boundary.  */
+  size = vec->size;
+  alc = vec->alc;
+  aligned = (size + 7) & ~ (size_t) 7;
+  alc -= aligned - size;
+
+  backtrace_free (state, (char *) vec->base + aligned, alc,
+		  error_callback, data);
+  vec->alc = 0;
+  if (vec->size == 0)
+    vec->base = NULL;
+  return 1;
+}

libbacktrace/mmapio.c

@@ -0,0 +1,110 @@
+/* mmapio.c -- File views using mmap.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+#ifndef HAVE_DECL_GETPAGESIZE
+extern int getpagesize (void);
+#endif
+
+#ifndef MAP_FAILED
+#define MAP_FAILED ((void *)-1)
+#endif
+
+/* This file implements file views and memory allocation when mmap is
+   available.  */
+
+/* Create a view of SIZE bytes from DESCRIPTOR at OFFSET.  */
+
+int
+backtrace_get_view (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		    int descriptor, off_t offset, uint64_t size,
+		    backtrace_error_callback error_callback,
+		    void *data, struct backtrace_view *view)
+{
+  size_t pagesize;
+  unsigned int inpage;
+  off_t pageoff;
+  void *map;
+
+  if ((uint64_t) (size_t) size != size)
+    {
+      error_callback (data, "file size too large", 0);
+      return 0;
+    }
+
+  pagesize = getpagesize ();
+  inpage = offset % pagesize;
+  pageoff = offset - inpage;
+
+  size += inpage;
+  size = (size + (pagesize - 1)) & ~ (pagesize - 1);
+
+  map = mmap (NULL, size, PROT_READ, MAP_PRIVATE, descriptor, pageoff);
+  if (map == MAP_FAILED)
+    {
+      error_callback (data, "mmap", errno);
+      return 0;
+    }
+
+  view->data = (char *) map + inpage;
+  view->base = map;
+  view->len = size;
+
+  return 1;
+}
+
+/* Release a view read by backtrace_get_view.  */
+
+void
+backtrace_release_view (struct backtrace_state *state ATTRIBUTE_UNUSED,
+			struct backtrace_view *view,
+			backtrace_error_callback error_callback,
+			void *data)
+{
+  union {
+    const void *cv;
+    void *v;
+  } const_cast;
+
+  const_cast.cv = view->base;
+  if (munmap (const_cast.v, view->len) < 0)
+    error_callback (data, "munmap", errno);
+}

libbacktrace/mtest.c

@@ -0,0 +1,410 @@
+/* mtest.c -- Minidebug test for libbacktrace library
+   Copyright (C) 2020-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* This program tests using libbacktrace with a program that uses the
+   minidebuginfo format in a .gnu_debugdata section.  See
+   https://sourceware.org/gdb/current/onlinedocs/gdb/MiniDebugInfo.html
+   for a bit more information about minidebuginfo.  What is relevant
+   for libbacktrace is that we have just a symbol table, with no debug
+   info, so we should be able to do a function backtrace, but we can't
+   do a file/line backtrace.  */
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "testlib.h"
+
+static int test1 (void) __attribute__ ((noinline, noclone, unused));
+static int f2 (int) __attribute__ ((noinline, noclone));
+static int f3 (int, int) __attribute__ ((noinline, noclone));
+
+/* Collected PC values.  */
+
+static uintptr_t addrs[20];
+
+/* The backtrace callback function.  This is like callback_one in
+   testlib.c, but it saves the PC also.  */
+
+static int
+callback_mtest (void *vdata, uintptr_t pc, const char *filename, int lineno,
+		const char *function)
+{
+  struct bdata *data = (struct bdata *) vdata;
+
+  if (data->index >= sizeof addrs / sizeof addrs[0])
+    {
+      fprintf (stderr, "callback_mtest: callback called too many times\n");
+      data->failed = 1;
+      return 1;
+    }
+
+  addrs[data->index] = pc;
+
+  return callback_one (vdata, pc, filename, lineno, function);
+}
+
+/* Test the backtrace function with non-inlined functions.  (We don't
+   test with inlined functions because they won't work with minidebug
+   anyhow.)  */
+
+static int
+test1 (void)
+{
+  /* Returning a value here and elsewhere avoids a tailcall which
+     would mess up the backtrace.  */
+  return f2 (__LINE__) + 1;
+}
+
+static int
+f2 (int f1line)
+{
+  return f3 (f1line, __LINE__) + 2;
+}
+
+static int
+f3 (int f1line __attribute__ ((unused)), int f2line __attribute__ ((unused)))
+{
+  struct info all[20];
+  struct bdata data;
+  int i;
+  size_t j;
+
+  data.all = &all[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  i = backtrace_full (state, 0, callback_mtest, error_callback_one, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test1: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (data.index < 3)
+    {
+      fprintf (stderr,
+	       "test1: not enough frames; got %zu, expected at least 3\n",
+	       data.index);
+      data.failed = 1;
+    }
+
+  /* When using minidebug we don't expect the function name here.  */
+
+  for (j = 0; j < 3 && j < data.index; j++)
+    {
+      if (all[j].function == NULL)
+	{
+	  struct symdata symdata;
+
+	  symdata.name = NULL;
+	  symdata.val = 0;
+	  symdata.size = 0;
+	  symdata.failed = 0;
+
+	  i = backtrace_syminfo (state, addrs[j], callback_three,
+				 error_callback_three, &symdata);
+	  if (i == 0)
+	    {
+	      fprintf (stderr,
+		       ("test1: [%zu], unexpected return value from "
+			"backtrace_syminfo %d\n"),
+		       j, i);
+	      data.failed = 1;
+	    }
+	  else if (symdata.name == NULL)
+	    {
+	      fprintf (stderr, "test1: [%zu]: syminfo did not find name\n", j);
+	      data.failed = 1;
+	    }
+	  else
+	    all[j].function = strdup (symdata.name);
+	}
+    }
+
+  if (data.index > 0)
+    {
+      if (all[0].function == NULL)
+	{
+	  fprintf (stderr, "test1: [0]: missing function name\n");
+	  data.failed = 1;
+	}
+      else if (strcmp (all[0].function, "f3") != 0)
+	{
+	  fprintf (stderr, "test1: [0]: got %s expected %s\n",
+		   all[0].function, "f3");
+	  data.failed = 1;
+	}
+    }
+
+  if (data.index > 1)
+    {
+      if (all[1].function == NULL)
+	{
+	  fprintf (stderr, "test1: [1]: missing function name\n");
+	  data.failed = 1;
+	}
+      else if (strcmp (all[1].function, "f2") != 0)
+	{
+	  fprintf (stderr, "test1: [1]: got %s expected %s\n",
+		   all[0].function, "f2");
+	  data.failed = 1;
+	}
+    }
+
+  if (data.index > 2)
+    {
+      if (all[2].function == NULL)
+	{
+	  fprintf (stderr, "test1: [2]: missing function name\n");
+	  data.failed = 1;
+	}
+      else if (strcmp (all[2].function, "test1") != 0)
+	{
+	  fprintf (stderr, "test1: [2]: got %s expected %s\n",
+		   all[0].function, "test1");
+	  data.failed = 1;
+	}
+    }
+
+  printf ("%s: backtrace_full noinline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+/* Test the backtrace_simple function with non-inlined functions.  */
+
+static int test3 (void) __attribute__ ((noinline, noclone, unused));
+static int f22 (int) __attribute__ ((noinline, noclone));
+static int f23 (int, int) __attribute__ ((noinline, noclone));
+
+static int
+test3 (void)
+{
+  return f22 (__LINE__) + 1;
+}
+
+static int
+f22 (int f1line)
+{
+  return f23 (f1line, __LINE__) + 2;
+}
+
+static int
+f23 (int f1line __attribute__ ((unused)), int f2line __attribute__ ((unused)))
+{
+  uintptr_t addrs[20];
+  struct sdata data;
+  int i;
+
+  data.addrs = &addrs[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  i = backtrace_simple (state, 0, callback_two, error_callback_two, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test3: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (!data.failed)
+    {
+      int j;
+
+      for (j = 0; j < 3; ++j)
+	{
+	  struct symdata symdata;
+
+	  symdata.name = NULL;
+	  symdata.val = 0;
+	  symdata.size = 0;
+	  symdata.failed = 0;
+
+	  i = backtrace_syminfo (state, addrs[j], callback_three,
+				 error_callback_three, &symdata);
+	  if (i == 0)
+	    {
+	      fprintf (stderr,
+		       ("test3: [%d]: unexpected return value "
+			"from backtrace_syminfo %d\n"),
+		       j, i);
+	      symdata.failed = 1;
+	    }
+
+	  if (!symdata.failed)
+	    {
+	      const char *expected;
+
+	      switch (j)
+		{
+		case 0:
+		  expected = "f23";
+		  break;
+		case 1:
+		  expected = "f22";
+		  break;
+		case 2:
+		  expected = "test3";
+		  break;
+		default:
+		  assert (0);
+		}
+
+	      if (symdata.name == NULL)
+		{
+		  fprintf (stderr, "test3: [%d]: NULL syminfo name\n", j);
+		  symdata.failed = 1;
+		}
+	      /* Use strncmp, not strcmp, because GCC might create a
+		 clone.  */
+	      else if (strncmp (symdata.name, expected, strlen (expected))
+		       != 0)
+		{
+		  fprintf (stderr,
+			   ("test3: [%d]: unexpected syminfo name "
+			    "got %s expected %s\n"),
+			   j, symdata.name, expected);
+		  symdata.failed = 1;
+		}
+	    }
+
+	  if (symdata.failed)
+	    data.failed = 1;
+	}
+    }
+
+  printf ("%s: backtrace_simple noinline\n", data.failed ? "FAIL" : "PASS");
+
+  if (data.failed)
+    ++failures;
+
+  return failures;
+}
+
+int test5 (void) __attribute__ ((unused));
+
+int global = 1;
+
+int
+test5 (void)
+{
+  struct symdata symdata;
+  int i;
+  uintptr_t addr = (uintptr_t) &global;
+
+  if (sizeof (global) > 1)
+    addr += 1;
+
+  symdata.name = NULL;
+  symdata.val = 0;
+  symdata.size = 0;
+  symdata.failed = 0;
+
+  i = backtrace_syminfo (state, addr, callback_three,
+			 error_callback_three, &symdata);
+  if (i == 0)
+    {
+      fprintf (stderr,
+	       "test5: unexpected return value from backtrace_syminfo %d\n",
+	       i);
+      symdata.failed = 1;
+    }
+
+  if (!symdata.failed)
+    {
+      if (symdata.name == NULL)
+	{
+	  fprintf (stderr, "test5: NULL syminfo name\n");
+	  symdata.failed = 1;
+	}
+      else if (!(strncmp (symdata.name, "global", 6) == 0
+		 && (symdata.name[6] == '\0'|| symdata.name[6] == '.')))
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo name got %s expected %s\n",
+		   symdata.name, "global");
+	  symdata.failed = 1;
+	}
+      else if (symdata.val != (uintptr_t) &global)
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo value got %lx expected %lx\n",
+		   (unsigned long) symdata.val,
+		   (unsigned long) (uintptr_t) &global);
+	  symdata.failed = 1;
+	}
+      else if (symdata.size != sizeof (global))
+	{
+	  fprintf (stderr,
+		   "test5: unexpected syminfo size got %lx expected %lx\n",
+		   (unsigned long) symdata.size,
+		   (unsigned long) sizeof (global));
+	  symdata.failed = 1;
+	}
+    }
+
+  printf ("%s: backtrace_syminfo variable\n",
+	  symdata.failed ? "FAIL" : "PASS");
+
+  if (symdata.failed)
+    ++failures;
+
+  return failures;
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+#if BACKTRACE_SUPPORTED
+  test1 ();
+  test3 ();
+#if BACKTRACE_SUPPORTS_DATA
+  test5 ();
+#endif
+#endif
+
+  exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/nounwind.c

@@ -0,0 +1,66 @@
+/* backtrace.c -- Entry point for stack backtrace library.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <sys/types.h>
+
+#include "backtrace.h"
+
+#include "internal.h"
+
+/* This source file is compiled if the unwind library is not
+   available.  */
+
+int
+backtrace_full (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		int skip ATTRIBUTE_UNUSED,
+		backtrace_full_callback callback ATTRIBUTE_UNUSED,
+		backtrace_error_callback error_callback, void *data)
+{
+  error_callback (data,
+		  "no stack trace because unwind library not available",
+		  0);
+  return 0;
+}
+
+int
+backtrace_simple (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		  int skip ATTRIBUTE_UNUSED,
+		  backtrace_simple_callback callback ATTRIBUTE_UNUSED,
+		  backtrace_error_callback error_callback, void *data)
+{
+  error_callback (data,
+		  "no stack trace because unwind library not available",
+		  0);
+  return 0;
+}

libbacktrace/pecoff.c

@@ -0,0 +1,935 @@
+/* pecoff.c -- Get debug data from a PE/COFFF file for backtraces.
+   Copyright (C) 2015-2021 Free Software Foundation, Inc.
+   Adapted from elf.c by Tristan Gingold, AdaCore.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+/* Coff file header.  */
+
+typedef struct {
+  uint16_t machine;
+  uint16_t number_of_sections;
+  uint32_t time_date_stamp;
+  uint32_t pointer_to_symbol_table;
+  uint32_t number_of_symbols;
+  uint16_t size_of_optional_header;
+  uint16_t characteristics;
+} b_coff_file_header;
+
+/* Coff optional header.  */
+
+typedef struct {
+  uint16_t magic;
+  uint8_t  major_linker_version;
+  uint8_t  minor_linker_version;
+  uint32_t size_of_code;
+  uint32_t size_of_initialized_data;
+  uint32_t size_of_uninitialized_data;
+  uint32_t address_of_entry_point;
+  uint32_t base_of_code;
+  union {
+    struct {
+      uint32_t base_of_data;
+      uint32_t image_base;
+    } pe;
+    struct {
+      uint64_t image_base;
+    } pep;
+  } u;
+} b_coff_optional_header;
+
+/* Values of magic in optional header.  */
+
+#define PE_MAGIC 0x10b		/* PE32 executable.  */
+#define PEP_MAGIC 0x20b		/* PE32+ executable (for 64bit targets).  */
+
+/* Coff section header.  */
+
+typedef struct {
+  char name[8];
+  uint32_t virtual_size;
+  uint32_t virtual_address;
+  uint32_t size_of_raw_data;
+  uint32_t pointer_to_raw_data;
+  uint32_t pointer_to_relocations;
+  uint32_t pointer_to_line_numbers;
+  uint16_t number_of_relocations;
+  uint16_t number_of_line_numbers;
+  uint32_t characteristics;
+} b_coff_section_header;
+
+/* Coff symbol name.  */
+
+typedef union {
+  char short_name[8];
+  struct {
+    unsigned char zeroes[4];
+    unsigned char off[4];
+  } long_name;
+} b_coff_name;
+
+/* Coff symbol (external representation which is unaligned).  */
+
+typedef struct {
+  b_coff_name name;
+  unsigned char value[4];
+  unsigned char section_number[2];
+  unsigned char type[2];
+  unsigned char storage_class;
+  unsigned char number_of_aux_symbols;
+} b_coff_external_symbol;
+
+/* Symbol types.  */
+
+#define N_TBSHFT 4			/* Shift for the derived type.  */
+#define IMAGE_SYM_DTYPE_FUNCTION 2	/* Function derived type.  */
+
+/* Size of a coff symbol.  */
+
+#define SYM_SZ 18
+
+/* Coff symbol, internal representation (aligned).  */
+
+typedef struct {
+  const char *name;
+  uint32_t value;
+  int16_t sec;
+  uint16_t type;
+  uint16_t sc;
+} b_coff_internal_symbol;
+
+/* Names of sections, indexed by enum dwarf_section in internal.h.  */
+
+static const char * const debug_section_names[DEBUG_MAX] =
+{
+  ".debug_info",
+  ".debug_line",
+  ".debug_abbrev",
+  ".debug_ranges",
+  ".debug_str",
+  ".debug_addr",
+  ".debug_str_offsets",
+  ".debug_line_str",
+  ".debug_rnglists"
+};
+
+/* Information we gather for the sections we care about.  */
+
+struct debug_section_info
+{
+  /* Section file offset.  */
+  off_t offset;
+  /* Section size.  */
+  size_t size;
+};
+
+/* Information we keep for an coff symbol.  */
+
+struct coff_symbol
+{
+  /* The name of the symbol.  */
+  const char *name;
+  /* The address of the symbol.  */
+  uintptr_t address;
+};
+
+/* Information to pass to coff_syminfo.  */
+
+struct coff_syminfo_data
+{
+  /* Symbols for the next module.  */
+  struct coff_syminfo_data *next;
+  /* The COFF symbols, sorted by address.  */
+  struct coff_symbol *symbols;
+  /* The number of symbols.  */
+  size_t count;
+};
+
+/* A dummy callback function used when we can't find any debug info.  */
+
+static int
+coff_nodebug (struct backtrace_state *state ATTRIBUTE_UNUSED,
+	      uintptr_t pc ATTRIBUTE_UNUSED,
+	      backtrace_full_callback callback ATTRIBUTE_UNUSED,
+	      backtrace_error_callback error_callback, void *data)
+{
+  error_callback (data, "no debug info in PE/COFF executable", -1);
+  return 0;
+}
+
+/* A dummy callback function used when we can't find a symbol
+   table.  */
+
+static void
+coff_nosyms (struct backtrace_state *state ATTRIBUTE_UNUSED,
+	     uintptr_t addr ATTRIBUTE_UNUSED,
+	     backtrace_syminfo_callback callback ATTRIBUTE_UNUSED,
+	     backtrace_error_callback error_callback, void *data)
+{
+  error_callback (data, "no symbol table in PE/COFF executable", -1);
+}
+
+/* Read a potentially unaligned 4 byte word at P, using native endianness.  */
+
+static uint32_t
+coff_read4 (const unsigned char *p)
+{
+  uint32_t res;
+
+  memcpy (&res, p, 4);
+  return res;
+}
+
+/* Read a potentially unaligned 2 byte word at P, using native endianness.
+   All 2 byte word in symbols are always aligned, but for coherency all
+   fields are declared as char arrays.  */
+
+static uint16_t
+coff_read2 (const unsigned char *p)
+{
+  uint16_t res;
+
+  memcpy (&res, p, sizeof (res));
+  return res;
+}
+
+/* Return the length (without the trailing 0) of a COFF short name.  */
+
+static size_t
+coff_short_name_len (const char *name)
+{
+  int i;
+
+  for (i = 0; i < 8; i++)
+    if (name[i] == 0)
+      return i;
+  return 8;
+}
+
+/* Return true iff COFF short name CNAME is the same as NAME (a NUL-terminated
+   string).  */
+
+static int
+coff_short_name_eq (const char *name, const char *cname)
+{
+  int i;
+
+  for (i = 0; i < 8; i++)
+    {
+      if (name[i] != cname[i])
+	return 0;
+      if (name[i] == 0)
+	return 1;
+    }
+  return name[8] == 0;
+}
+
+/* Return true iff NAME is the same as string at offset OFF.  */
+
+static int
+coff_long_name_eq (const char *name, unsigned int off,
+		   struct backtrace_view *str_view)
+{
+  if (off >= str_view->len)
+    return 0;
+  return strcmp (name, (const char *)str_view->data + off) == 0;
+}
+
+/* Compare struct coff_symbol for qsort.  */
+
+static int
+coff_symbol_compare (const void *v1, const void *v2)
+{
+  const struct coff_symbol *e1 = (const struct coff_symbol *) v1;
+  const struct coff_symbol *e2 = (const struct coff_symbol *) v2;
+
+  if (e1->address < e2->address)
+    return -1;
+  else if (e1->address > e2->address)
+    return 1;
+  else
+    return 0;
+}
+
+/* Convert SYM to internal (and aligned) format ISYM, using string table
+   from STRTAB and STRTAB_SIZE, and number of sections SECTS_NUM.
+   Return -1 in case of error (invalid section number or string index).  */
+
+static int
+coff_expand_symbol (b_coff_internal_symbol *isym,
+		    const b_coff_external_symbol *sym,
+		    uint16_t sects_num,
+		    const unsigned char *strtab, size_t strtab_size)
+{
+  isym->type = coff_read2 (sym->type);
+  isym->sec = coff_read2 (sym->section_number);
+  isym->sc = sym->storage_class;
+
+  if (isym->sec > 0 && (uint16_t) isym->sec > sects_num)
+    return -1;
+  if (sym->name.short_name[0] != 0)
+    isym->name = sym->name.short_name;
+  else
+    {
+      uint32_t off = coff_read4 (sym->name.long_name.off);
+
+      if (off >= strtab_size)
+	return -1;
+      isym->name = (const char *) strtab + off;
+    }
+  return 0;
+}
+
+/* Return true iff SYM is a defined symbol for a function.  Data symbols
+   aren't considered because they aren't easily identified (same type as
+   section names, presence of symbols defined by the linker script).  */
+
+static int
+coff_is_function_symbol (const b_coff_internal_symbol *isym)
+{
+  return (isym->type >> N_TBSHFT) == IMAGE_SYM_DTYPE_FUNCTION
+    && isym->sec > 0;
+}
+
+/* Initialize the symbol table info for coff_syminfo.  */
+
+static int
+coff_initialize_syminfo (struct backtrace_state *state,
+			 uintptr_t base_address, int is_64,
+			 const b_coff_section_header *sects, size_t sects_num,
+			 const b_coff_external_symbol *syms, size_t syms_size,
+			 const unsigned char *strtab, size_t strtab_size,
+			 backtrace_error_callback error_callback,
+			 void *data, struct coff_syminfo_data *sdata)
+{
+  size_t syms_count;
+  char *coff_symstr;
+  size_t coff_symstr_len;
+  size_t coff_symbol_count;
+  size_t coff_symbol_size;
+  struct coff_symbol *coff_symbols;
+  struct coff_symbol *coff_sym;
+  char *coff_str;
+  size_t i;
+
+  syms_count = syms_size / SYM_SZ;
+
+  /* We only care about function symbols.  Count them.  Also count size of
+     strings for in-symbol names.  */
+  coff_symbol_count = 0;
+  coff_symstr_len = 0;
+  for (i = 0; i < syms_count; ++i)
+    {
+      const b_coff_external_symbol *asym = &syms[i];
+      b_coff_internal_symbol isym;
+
+      if (coff_expand_symbol (&isym, asym, sects_num, strtab, strtab_size) < 0)
+	{
+	  error_callback (data, "invalid section or offset in coff symbol", 0);
+	  return 0;
+	}
+      if (coff_is_function_symbol (&isym))
+	{
+	  ++coff_symbol_count;
+	  if (asym->name.short_name[0] != 0)
+	    coff_symstr_len += coff_short_name_len (asym->name.short_name) + 1;
+	}
+
+      i += asym->number_of_aux_symbols;
+    }
+
+  coff_symbol_size = (coff_symbol_count + 1) * sizeof (struct coff_symbol);
+  coff_symbols = ((struct coff_symbol *)
+		  backtrace_alloc (state, coff_symbol_size, error_callback,
+				   data));
+  if (coff_symbols == NULL)
+    return 0;
+
+  /* Allocate memory for symbols strings.  */
+  if (coff_symstr_len > 0)
+    {
+      coff_symstr = ((char *)
+		     backtrace_alloc (state, coff_symstr_len, error_callback,
+				      data));
+      if (coff_symstr == NULL)
+	{
+	  backtrace_free (state, coff_symbols, coff_symbol_size,
+			  error_callback, data);
+	  return 0;
+	}
+    }
+  else
+    coff_symstr = NULL;
+
+  /* Copy symbols.  */
+  coff_sym = coff_symbols;
+  coff_str = coff_symstr;
+  for (i = 0; i < syms_count; ++i)
+    {
+      const b_coff_external_symbol *asym = &syms[i];
+      b_coff_internal_symbol isym;
+
+      if (coff_expand_symbol (&isym, asym, sects_num, strtab, strtab_size))
+	{
+	  /* Should not fail, as it was already tested in the previous
+	     loop.  */
+	  abort ();
+	}
+      if (coff_is_function_symbol (&isym))
+	{
+	  const char *name;
+	  int16_t secnum;
+
+	  if (asym->name.short_name[0] != 0)
+	    {
+	      size_t len = coff_short_name_len (isym.name);
+	      name = coff_str;
+	      memcpy (coff_str, isym.name, len);
+	      coff_str[len] = 0;
+	      coff_str += len + 1;
+	    }
+	  else
+	    name = isym.name;
+
+	  if (!is_64)
+	    {
+	      /* Strip leading '_'.  */
+	      if (name[0] == '_')
+		name++;
+	    }
+
+	  /* Symbol value is section relative, so we need to read the address
+	     of its section.  */
+	  secnum = coff_read2 (asym->section_number);
+
+	  coff_sym->name = name;
+	  coff_sym->address = (coff_read4 (asym->value)
+			       + sects[secnum - 1].virtual_address
+			       + base_address);
+	  coff_sym++;
+	}
+
+      i += asym->number_of_aux_symbols;
+    }
+
+  /* End of symbols marker.  */
+  coff_sym->name = NULL;
+  coff_sym->address = -1;
+
+  backtrace_qsort (coff_symbols, coff_symbol_count,
+		   sizeof (struct coff_symbol), coff_symbol_compare);
+
+  sdata->next = NULL;
+  sdata->symbols = coff_symbols;
+  sdata->count = coff_symbol_count;
+
+  return 1;
+}
+
+/* Add EDATA to the list in STATE.  */
+
+static void
+coff_add_syminfo_data (struct backtrace_state *state,
+		       struct coff_syminfo_data *sdata)
+{
+  if (!state->threaded)
+    {
+      struct coff_syminfo_data **pp;
+
+      for (pp = (struct coff_syminfo_data **) (void *) &state->syminfo_data;
+	   *pp != NULL;
+	   pp = &(*pp)->next)
+	;
+      *pp = sdata;
+    }
+  else
+    {
+      while (1)
+	{
+	  struct coff_syminfo_data **pp;
+
+	  pp = (struct coff_syminfo_data **) (void *) &state->syminfo_data;
+
+	  while (1)
+	    {
+	      struct coff_syminfo_data *p;
+
+	      p = backtrace_atomic_load_pointer (pp);
+
+	      if (p == NULL)
+		break;
+
+	      pp = &p->next;
+	    }
+
+	  if (__sync_bool_compare_and_swap (pp, NULL, sdata))
+	    break;
+	}
+    }
+}
+
+/* Compare an ADDR against an elf_symbol for bsearch.  We allocate one
+   extra entry in the array so that this can look safely at the next
+   entry.  */
+
+static int
+coff_symbol_search (const void *vkey, const void *ventry)
+{
+  const uintptr_t *key = (const uintptr_t *) vkey;
+  const struct coff_symbol *entry = (const struct coff_symbol *) ventry;
+  uintptr_t addr;
+
+  addr = *key;
+  if (addr < entry->address)
+    return -1;
+  else if (addr >= entry[1].address)
+    return 1;
+  else
+    return 0;
+}
+
+/* Return the symbol name and value for an ADDR.  */
+
+static void
+coff_syminfo (struct backtrace_state *state, uintptr_t addr,
+	      backtrace_syminfo_callback callback,
+	      backtrace_error_callback error_callback ATTRIBUTE_UNUSED,
+	      void *data)
+{
+  struct coff_syminfo_data *sdata;
+  struct coff_symbol *sym = NULL;
+
+  if (!state->threaded)
+    {
+      for (sdata = (struct coff_syminfo_data *) state->syminfo_data;
+	   sdata != NULL;
+	   sdata = sdata->next)
+	{
+	  sym = ((struct coff_symbol *)
+		 bsearch (&addr, sdata->symbols, sdata->count,
+			  sizeof (struct coff_symbol), coff_symbol_search));
+	  if (sym != NULL)
+	    break;
+	}
+    }
+  else
+    {
+      struct coff_syminfo_data **pp;
+
+      pp = (struct coff_syminfo_data **) (void *) &state->syminfo_data;
+      while (1)
+	{
+	  sdata = backtrace_atomic_load_pointer (pp);
+	  if (sdata == NULL)
+	    break;
+
+	  sym = ((struct coff_symbol *)
+		 bsearch (&addr, sdata->symbols, sdata->count,
+			  sizeof (struct coff_symbol), coff_symbol_search));
+	  if (sym != NULL)
+	    break;
+
+	  pp = &sdata->next;
+	}
+    }
+
+  if (sym == NULL)
+    callback (data, addr, NULL, 0, 0);
+  else
+    callback (data, addr, sym->name, sym->address, 0);
+}
+
+/* Add the backtrace data for one PE/COFF file.  Returns 1 on success,
+   0 on failure (in both cases descriptor is closed).  */
+
+static int
+coff_add (struct backtrace_state *state, int descriptor,
+	  backtrace_error_callback error_callback, void *data,
+	  fileline *fileline_fn, int *found_sym, int *found_dwarf)
+{
+  struct backtrace_view fhdr_view;
+  off_t fhdr_off;
+  int magic_ok;
+  b_coff_file_header fhdr;
+  off_t opt_sects_off;
+  size_t opt_sects_size;
+  unsigned int sects_num;
+  struct backtrace_view sects_view;
+  int sects_view_valid;
+  const b_coff_optional_header *opt_hdr;
+  const b_coff_section_header *sects;
+  struct backtrace_view str_view;
+  int str_view_valid;
+  size_t str_size;
+  off_t str_off;
+  struct backtrace_view syms_view;
+  off_t syms_off;
+  size_t syms_size;
+  int syms_view_valid;
+  unsigned int syms_num;
+  unsigned int i;
+  struct debug_section_info sections[DEBUG_MAX];
+  off_t min_offset;
+  off_t max_offset;
+  struct backtrace_view debug_view;
+  int debug_view_valid;
+  int is_64;
+  uintptr_t image_base;
+  struct dwarf_sections dwarf_sections;
+
+  *found_sym = 0;
+  *found_dwarf = 0;
+
+  sects_view_valid = 0;
+  syms_view_valid = 0;
+  str_view_valid = 0;
+  debug_view_valid = 0;
+
+  /* Map the MS-DOS stub (if any) and extract file header offset.  */
+  if (!backtrace_get_view (state, descriptor, 0, 0x40, error_callback,
+			   data, &fhdr_view))
+    goto fail;
+
+  {
+    const unsigned char *vptr = fhdr_view.data;
+
+    if (vptr[0] == 'M' && vptr[1] == 'Z')
+      fhdr_off = coff_read4 (vptr + 0x3c);
+    else
+      fhdr_off = 0;
+  }
+
+  backtrace_release_view (state, &fhdr_view, error_callback, data);
+
+  /* Map the coff file header.  */
+  if (!backtrace_get_view (state, descriptor, fhdr_off,
+			   sizeof (b_coff_file_header) + 4,
+			   error_callback, data, &fhdr_view))
+    goto fail;
+
+  if (fhdr_off != 0)
+    {
+      const char *magic = (const char *) fhdr_view.data;
+      magic_ok = memcmp (magic, "PE\0", 4) == 0;
+      fhdr_off += 4;
+
+      memcpy (&fhdr, fhdr_view.data + 4, sizeof fhdr);
+    }
+  else
+    {
+      memcpy (&fhdr, fhdr_view.data, sizeof fhdr);
+      /* TODO: test fhdr.machine for coff but non-PE platforms.  */
+      magic_ok = 0;
+    }
+  backtrace_release_view (state, &fhdr_view, error_callback, data);
+
+  if (!magic_ok)
+    {
+      error_callback (data, "executable file is not COFF", 0);
+      goto fail;
+    }
+
+  sects_num = fhdr.number_of_sections;
+  syms_num = fhdr.number_of_symbols;
+
+  opt_sects_off = fhdr_off + sizeof (fhdr);
+  opt_sects_size = (fhdr.size_of_optional_header
+		    + sects_num * sizeof (b_coff_section_header));
+
+  /* To translate PC to file/line when using DWARF, we need to find
+     the .debug_info and .debug_line sections.  */
+
+  /* Read the optional header and the section headers.  */
+
+  if (!backtrace_get_view (state, descriptor, opt_sects_off, opt_sects_size,
+			   error_callback, data, &sects_view))
+    goto fail;
+  sects_view_valid = 1;
+  opt_hdr = (const b_coff_optional_header *) sects_view.data;
+  sects = (const b_coff_section_header *)
+    (sects_view.data + fhdr.size_of_optional_header);
+
+  is_64 = 0;
+  if (fhdr.size_of_optional_header > sizeof (*opt_hdr))
+    {
+      if (opt_hdr->magic == PE_MAGIC)
+	image_base = opt_hdr->u.pe.image_base;
+      else if (opt_hdr->magic == PEP_MAGIC)
+	{
+	  image_base = opt_hdr->u.pep.image_base;
+	  is_64 = 1;
+	}
+      else
+	{
+	  error_callback (data, "bad magic in PE optional header", 0);
+	  goto fail;
+	}
+    }
+  else
+    image_base = 0;
+
+  /* Read the symbol table and the string table.  */
+
+  if (fhdr.pointer_to_symbol_table == 0)
+    {
+      /* No symbol table, no string table.  */
+      str_off = 0;
+      str_size = 0;
+      syms_num = 0;
+      syms_size = 0;
+    }
+  else
+    {
+      /* Symbol table is followed by the string table.  The string table
+	 starts with its length (on 4 bytes).
+	 Map the symbol table and the length of the string table.  */
+      syms_off = fhdr.pointer_to_symbol_table;
+      syms_size = syms_num * SYM_SZ;
+
+      if (!backtrace_get_view (state, descriptor, syms_off, syms_size + 4,
+			       error_callback, data, &syms_view))
+	goto fail;
+      syms_view_valid = 1;
+
+      str_size = coff_read4 (syms_view.data + syms_size);
+
+      str_off = syms_off + syms_size;
+
+      if (str_size > 4)
+	{
+	  /* Map string table (including the length word).  */
+
+	  if (!backtrace_get_view (state, descriptor, str_off, str_size,
+				   error_callback, data, &str_view))
+	    goto fail;
+	  str_view_valid = 1;
+	}
+    }
+
+  memset (sections, 0, sizeof sections);
+
+  /* Look for the symbol table.  */
+  for (i = 0; i < sects_num; ++i)
+    {
+      const b_coff_section_header *s = sects + i;
+      unsigned int str_off;
+      int j;
+
+      if (s->name[0] == '/')
+	{
+	  /* Extended section name.  */
+	  str_off = atoi (s->name + 1);
+	}
+      else
+	str_off = 0;
+
+      for (j = 0; j < (int) DEBUG_MAX; ++j)
+	{
+	  const char *dbg_name = debug_section_names[j];
+	  int match;
+
+	  if (str_off != 0)
+	    match = coff_long_name_eq (dbg_name, str_off, &str_view);
+	  else
+	    match = coff_short_name_eq (dbg_name, s->name);
+	  if (match)
+	    {
+	      sections[j].offset = s->pointer_to_raw_data;
+	      sections[j].size = s->virtual_size <= s->size_of_raw_data ?
+		s->virtual_size : s->size_of_raw_data;
+	      break;
+	    }
+	}
+    }
+
+  if (syms_num != 0)
+    {
+      struct coff_syminfo_data *sdata;
+
+      sdata = ((struct coff_syminfo_data *)
+	       backtrace_alloc (state, sizeof *sdata, error_callback, data));
+      if (sdata == NULL)
+	goto fail;
+
+      if (!coff_initialize_syminfo (state, image_base, is_64,
+				    sects, sects_num,
+				    syms_view.data, syms_size,
+				    str_view.data, str_size,
+				    error_callback, data, sdata))
+	{
+	  backtrace_free (state, sdata, sizeof *sdata, error_callback, data);
+	  goto fail;
+	}
+
+      *found_sym = 1;
+
+      coff_add_syminfo_data (state, sdata);
+    }
+
+  backtrace_release_view (state, &sects_view, error_callback, data);
+  sects_view_valid = 0;
+  if (syms_view_valid)
+    {
+      backtrace_release_view (state, &syms_view, error_callback, data);
+      syms_view_valid = 0;
+    }
+
+  /* Read all the debug sections in a single view, since they are
+     probably adjacent in the file.  We never release this view.  */
+
+  min_offset = 0;
+  max_offset = 0;
+  for (i = 0; i < (int) DEBUG_MAX; ++i)
+    {
+      off_t end;
+
+      if (sections[i].size == 0)
+	continue;
+      if (min_offset == 0 || sections[i].offset < min_offset)
+	min_offset = sections[i].offset;
+      end = sections[i].offset + sections[i].size;
+      if (end > max_offset)
+	max_offset = end;
+    }
+  if (min_offset == 0 || max_offset == 0)
+    {
+      if (!backtrace_close (descriptor, error_callback, data))
+	goto fail;
+      *fileline_fn = coff_nodebug;
+      return 1;
+    }
+
+  if (!backtrace_get_view (state, descriptor, min_offset,
+			   max_offset - min_offset,
+			   error_callback, data, &debug_view))
+    goto fail;
+  debug_view_valid = 1;
+
+  /* We've read all we need from the executable.  */
+  if (!backtrace_close (descriptor, error_callback, data))
+    goto fail;
+  descriptor = -1;
+
+  for (i = 0; i < (int) DEBUG_MAX; ++i)
+    {
+      size_t size = sections[i].size;
+      dwarf_sections.size[i] = size;
+      if (size == 0)
+	dwarf_sections.data[i] = NULL;
+      else
+	dwarf_sections.data[i] = ((const unsigned char *) debug_view.data
+				  + (sections[i].offset - min_offset));
+    }
+
+  if (!backtrace_dwarf_add (state, /* base_address */ 0, &dwarf_sections,
+			    0, /* FIXME: is_bigendian */
+			    NULL, /* altlink */
+			    error_callback, data, fileline_fn,
+			    NULL /* returned fileline_entry */))
+    goto fail;
+
+  *found_dwarf = 1;
+
+  return 1;
+
+ fail:
+  if (sects_view_valid)
+    backtrace_release_view (state, &sects_view, error_callback, data);
+  if (str_view_valid)
+    backtrace_release_view (state, &str_view, error_callback, data);
+  if (syms_view_valid)
+    backtrace_release_view (state, &syms_view, error_callback, data);
+  if (debug_view_valid)
+    backtrace_release_view (state, &debug_view, error_callback, data);
+  if (descriptor != -1)
+    backtrace_close (descriptor, error_callback, data);
+  return 0;
+}
+
+/* Initialize the backtrace data we need from an ELF executable.  At
+   the ELF level, all we need to do is find the debug info
+   sections.  */
+
+int
+backtrace_initialize (struct backtrace_state *state,
+		      const char *filename ATTRIBUTE_UNUSED, int descriptor,
+		      backtrace_error_callback error_callback,
+		      void *data, fileline *fileline_fn)
+{
+  int ret;
+  int found_sym;
+  int found_dwarf;
+  fileline coff_fileline_fn;
+
+  ret = coff_add (state, descriptor, error_callback, data,
+		  &coff_fileline_fn, &found_sym, &found_dwarf);
+  if (!ret)
+    return 0;
+
+  if (!state->threaded)
+    {
+      if (found_sym)
+	state->syminfo_fn = coff_syminfo;
+      else if (state->syminfo_fn == NULL)
+	state->syminfo_fn = coff_nosyms;
+    }
+  else
+    {
+      if (found_sym)
+	backtrace_atomic_store_pointer (&state->syminfo_fn, coff_syminfo);
+      else
+	(void) __sync_bool_compare_and_swap (&state->syminfo_fn, NULL,
+					     coff_nosyms);
+    }
+
+  if (!state->threaded)
+    {
+      if (state->fileline_fn == NULL || state->fileline_fn == coff_nodebug)
+	*fileline_fn = coff_fileline_fn;
+    }
+  else
+    {
+      fileline current_fn;
+
+      current_fn = backtrace_atomic_load_pointer (&state->fileline_fn);
+      if (current_fn == NULL || current_fn == coff_nodebug)
+	*fileline_fn = coff_fileline_fn;
+    }
+
+  return 1;
+}

libbacktrace/posix.c

@@ -0,0 +1,104 @@
+/* posix.c -- POSIX file I/O routines for the backtrace library.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+#ifndef O_BINARY
+#define O_BINARY 0
+#endif
+
+#ifndef O_CLOEXEC
+#define O_CLOEXEC 0
+#endif
+
+#ifndef FD_CLOEXEC
+#define FD_CLOEXEC 1
+#endif
+
+/* Open a file for reading.  */
+
+int
+backtrace_open (const char *filename, backtrace_error_callback error_callback,
+		void *data, int *does_not_exist)
+{
+  int descriptor;
+
+  if (does_not_exist != NULL)
+    *does_not_exist = 0;
+
+  descriptor = open (filename, (int) (O_RDONLY | O_BINARY | O_CLOEXEC));
+  if (descriptor < 0)
+    {
+      /* If DOES_NOT_EXIST is not NULL, then don't call ERROR_CALLBACK
+	 if the file does not exist.  We treat lacking permission to
+	 open the file as the file not existing; this case arises when
+	 running the libgo syscall package tests as root.  */
+      if (does_not_exist != NULL && (errno == ENOENT || errno == EACCES))
+	*does_not_exist = 1;
+      else
+	error_callback (data, filename, errno);
+      return -1;
+    }
+
+#ifdef HAVE_FCNTL
+  /* Set FD_CLOEXEC just in case the kernel does not support
+     O_CLOEXEC. It doesn't matter if this fails for some reason.
+     FIXME: At some point it should be safe to only do this if
+     O_CLOEXEC == 0.  */
+  fcntl (descriptor, F_SETFD, FD_CLOEXEC);
+#endif
+
+  return descriptor;
+}
+
+/* Close DESCRIPTOR.  */
+
+int
+backtrace_close (int descriptor, backtrace_error_callback error_callback,
+		 void *data)
+{
+  if (close (descriptor) < 0)
+    {
+      error_callback (data, "close", errno);
+      return 0;
+    }
+  return 1;
+}

libbacktrace/print.c

@@ -0,0 +1,92 @@
+/* print.c -- Print the current backtrace.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+/* Passed to callbacks.  */
+
+struct print_data
+{
+  struct backtrace_state *state;
+  FILE *f;
+};
+
+/* Print one level of a backtrace.  */
+
+static int
+print_callback (void *data, uintptr_t pc, const char *filename, int lineno,
+		const char *function)
+{
+  struct print_data *pdata = (struct print_data *) data;
+
+  fprintf (pdata->f, "0x%lx %s\n\t%s:%d\n",
+	   (unsigned long) pc,
+	   function == NULL ? "???" : function,
+	   filename == NULL ? "???" : filename,
+	   lineno);
+  return 0;
+}
+
+/* Print errors to stderr.  */
+
+static void
+error_callback (void *data, const char *msg, int errnum)
+{
+  struct print_data *pdata = (struct print_data *) data;
+
+  if (pdata->state->filename != NULL)
+    fprintf (stderr, "%s: ", pdata->state->filename);
+  fprintf (stderr, "libbacktrace: %s", msg);
+  if (errnum > 0)
+    fprintf (stderr, ": %s", strerror (errnum));
+  fputc ('\n', stderr);
+}
+
+/* Print a backtrace.  */
+
+void __attribute__((noinline))
+backtrace_print (struct backtrace_state *state, int skip, FILE *f)
+{
+  struct print_data data;
+
+  data.state = state;
+  data.f = f;
+  backtrace_full (state, skip + 1, print_callback, error_callback,
+		  (void *) &data);
+}

libbacktrace/read.c

@@ -0,0 +1,110 @@
+/* read.c -- File views without mmap.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+/* This file implements file views when mmap is not available.  */
+
+/* Create a view of SIZE bytes from DESCRIPTOR at OFFSET.  */
+
+int
+backtrace_get_view (struct backtrace_state *state, int descriptor,
+		    off_t offset, uint64_t size,
+		    backtrace_error_callback error_callback,
+		    void *data, struct backtrace_view *view)
+{
+  uint64_t got;
+  ssize_t r;
+
+  if ((uint64_t) (size_t) size != size)
+    {
+      error_callback (data, "file size too large", 0);
+      return 0;
+    }
+
+  if (lseek (descriptor, offset, SEEK_SET) < 0)
+    {
+      error_callback (data, "lseek", errno);
+      return 0;
+    }
+
+  view->base = backtrace_alloc (state, size, error_callback, data);
+  if (view->base == NULL)
+    return 0;
+  view->data = view->base;
+  view->len = size;
+
+  got = 0;
+  while (got < size)
+    {
+      r = read (descriptor, view->base, size - got);
+      if (r < 0)
+	{
+	  error_callback (data, "read", errno);
+	  free (view->base);
+	  return 0;
+	}
+      if (r == 0)
+	break;
+      got += (uint64_t) r;
+    }
+
+  if (got < size)
+    {
+      error_callback (data, "file too short", 0);
+      free (view->base);
+      return 0;
+    }
+
+  return 1;
+}
+
+/* Release a view read by backtrace_get_view.  */
+
+void
+backtrace_release_view (struct backtrace_state *state,
+			struct backtrace_view *view,
+			backtrace_error_callback error_callback,
+			void *data)
+{
+  backtrace_free (state, view->base, view->len, error_callback, data);
+  view->data = NULL;
+  view->base = NULL;
+}

libbacktrace/simple.c

@@ -0,0 +1,108 @@
+/* simple.c -- The backtrace_simple function.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include "unwind.h"
+#include "backtrace.h"
+
+/* The simple_backtrace routine.  */
+
+/* Data passed through _Unwind_Backtrace.  */
+
+struct backtrace_simple_data
+{
+  /* Number of frames to skip.  */
+  int skip;
+  /* Library state.  */
+  struct backtrace_state *state;
+  /* Callback routine.  */
+  backtrace_simple_callback callback;
+  /* Error callback routine.  */
+  backtrace_error_callback error_callback;
+  /* Data to pass to callback routine.  */
+  void *data;
+  /* Value to return from backtrace.  */
+  int ret;
+};
+
+/* Unwind library callback routine.  This is passed to
+   _Unwind_Backtrace.  */
+
+static _Unwind_Reason_Code
+simple_unwind (struct _Unwind_Context *context, void *vdata)
+{
+  struct backtrace_simple_data *bdata = (struct backtrace_simple_data *) vdata;
+  uintptr_t pc;
+  int ip_before_insn = 0;
+
+#ifdef HAVE_GETIPINFO
+  pc = _Unwind_GetIPInfo (context, &ip_before_insn);
+#else
+  pc = _Unwind_GetIP (context);
+#endif
+
+  if (bdata->skip > 0)
+    {
+      --bdata->skip;
+      return _URC_NO_REASON;
+    }
+
+  if (!ip_before_insn)
+    --pc;
+
+  bdata->ret = bdata->callback (bdata->data, pc);
+
+  if (bdata->ret != 0)
+    return _URC_END_OF_STACK;
+
+  return _URC_NO_REASON;
+}
+
+/* Get a simple stack backtrace.  */
+
+int __attribute__((noinline))
+backtrace_simple (struct backtrace_state *state, int skip,
+		  backtrace_simple_callback callback,
+		  backtrace_error_callback error_callback, void *data)
+{
+  struct backtrace_simple_data bdata;
+
+  bdata.skip = skip + 1;
+  bdata.state = state;
+  bdata.callback = callback;
+  bdata.error_callback = error_callback;
+  bdata.data = data;
+  bdata.ret = 0;
+  _Unwind_Backtrace (simple_unwind, &bdata);
+  return bdata.ret;
+}

libbacktrace/sort.c

@@ -0,0 +1,108 @@
+/* sort.c -- Sort without allocating memory
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <stddef.h>
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+/* The GNU glibc version of qsort allocates memory, which we must not
+   do if we are invoked by a signal handler.  So provide our own
+   sort.  */
+
+static void
+swap (char *a, char *b, size_t size)
+{
+  size_t i;
+
+  for (i = 0; i < size; i++, a++, b++)
+    {
+      char t;
+
+      t = *a;
+      *a = *b;
+      *b = t;
+    }
+}
+
+void
+backtrace_qsort (void *basearg, size_t count, size_t size,
+		 int (*compar) (const void *, const void *))
+{
+  char *base = (char *) basearg;
+  size_t i;
+  size_t mid;
+
+ tail_recurse:
+  if (count < 2)
+    return;
+
+  /* The symbol table and DWARF tables, which is all we use this
+     routine for, tend to be roughly sorted.  Pick the middle element
+     in the array as our pivot point, so that we are more likely to
+     cut the array in half for each recursion step.  */
+  swap (base, base + (count / 2) * size, size);
+
+  mid = 0;
+  for (i = 1; i < count; i++)
+    {
+      if ((*compar) (base, base + i * size) > 0)
+	{
+	  ++mid;
+	  if (i != mid)
+	    swap (base + mid * size, base + i * size, size);
+	}
+    }
+
+  if (mid > 0)
+    swap (base, base + mid * size, size);
+
+  /* Recurse with the smaller array, loop with the larger one.  That
+     ensures that our maximum stack depth is log count.  */
+  if (2 * mid < count)
+    {
+      backtrace_qsort (base, mid, size, compar);
+      base += (mid + 1) * size;
+      count -= mid + 1;
+      goto tail_recurse;
+    }
+  else
+    {
+      backtrace_qsort (base + (mid + 1) * size, count - (mid + 1),
+		       size, compar);
+      count = mid;
+      goto tail_recurse;
+    }
+}

libbacktrace/state.c

@@ -0,0 +1,72 @@
+/* state.c -- Create the backtrace state.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <string.h>
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+#include "internal.h"
+
+/* Create the backtrace state.  This will then be passed to all the
+   other routines.  */
+
+struct backtrace_state *
+backtrace_create_state (const char *filename, int threaded,
+			backtrace_error_callback error_callback,
+			void *data)
+{
+  struct backtrace_state init_state;
+  struct backtrace_state *state;
+
+#ifndef HAVE_SYNC_FUNCTIONS
+  if (threaded)
+    {
+      error_callback (data, "backtrace library does not support threads", 0);
+      return NULL;
+    }
+#endif
+
+  memset (&init_state, 0, sizeof init_state);
+  init_state.filename = filename;
+  init_state.threaded = threaded;
+
+  state = ((struct backtrace_state *)
+	   backtrace_alloc (&init_state, sizeof *state, error_callback, data));
+  if (state == NULL)
+    return NULL;
+  *state = init_state;
+
+  return state;
+}

libbacktrace/stest.c

@@ -0,0 +1,137 @@
+/* stest.c -- Test for libbacktrace internal sort function
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+/* Test the local qsort implementation.  */
+
+#define MAX 10
+
+struct test
+{
+  size_t count;
+  int input[MAX];
+  int output[MAX];
+};
+
+static struct test tests[] =
+  {
+    {
+      10,
+      { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 },
+      { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }
+    },
+    {
+      9,
+      { 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+      { 1, 2, 3, 4, 5, 6, 7, 8, 9 }
+    },
+    {
+      10,
+      { 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 },
+      { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 },
+    },
+    {
+      9,
+      { 9, 8, 7, 6, 5, 4, 3, 2, 1 },
+      { 1, 2, 3, 4, 5, 6, 7, 8, 9 },
+    },
+    {
+      10,
+      { 2, 4, 6, 8, 10, 1, 3, 5, 7, 9 },
+      { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 },
+    },
+    {
+      5,
+      { 4, 5, 3, 1, 2 },
+      { 1, 2, 3, 4, 5 },
+    },
+    {
+      5,
+      { 1, 1, 1, 1, 1 },
+      { 1, 1, 1, 1, 1 },
+    },
+    {
+      5,
+      { 1, 1, 2, 1, 1 },
+      { 1, 1, 1, 1, 2 },
+    },
+    {
+      5,
+      { 2, 1, 1, 1, 1 },
+      { 1, 1, 1, 1, 2 },
+    },
+  };
+
+static int
+compare (const void *a, const void *b)
+{
+  const int *ai = (const int *) a;
+  const int *bi = (const int *) b;
+
+  return *ai - *bi;
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED)
+{
+  int failures;
+  size_t i;
+  int a[MAX];
+
+  failures = 0;
+  for (i = 0; i < sizeof tests / sizeof tests[0]; i++)
+    {
+      memcpy (a, tests[i].input, tests[i].count * sizeof (int));
+      backtrace_qsort (a, tests[i].count, sizeof (int), compare);
+      if (memcmp (a, tests[i].output, tests[i].count * sizeof (int)) != 0)
+	{
+	  size_t j;
+
+	  fprintf (stderr, "test %d failed:", (int) i);
+	  for (j = 0; j < tests[i].count; j++)
+	    fprintf (stderr, " %d", a[j]);
+	  fprintf (stderr, "\n");
+	  ++failures;
+	}
+    }
+
+  exit (failures > 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/test_format.c

@@ -0,0 +1,55 @@
+/* test_format.c -- Test for libbacktrace library
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* This program tests the externally visible interfaces of the
+   libbacktrace library.  */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "filenames.h"
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "testlib.h"
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+  exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/testlib.c

@@ -0,0 +1,234 @@
+/* testlib.c -- test functions for libbacktrace library
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "filenames.h"
+
+#include "backtrace.h"
+
+#include "testlib.h"
+
+/* The backtrace state.  */
+
+void *state;
+
+/* The number of failures.  */
+
+int failures;
+
+/* Return the base name in a path.  */
+
+const char *
+base (const char *p)
+{
+  const char *last;
+  const char *s;
+
+  last = NULL;
+  for (s = p; *s != '\0'; ++s)
+    {
+      if (IS_DIR_SEPARATOR (*s))
+	last = s + 1;
+    }
+  return last != NULL ? last : p;
+}
+
+/* Check an entry in a struct info array.  */
+
+void
+check (const char *name, int index, const struct info *all, int want_lineno,
+       const char *want_function, const char *want_file, int *failed)
+{
+  if (*failed)
+    return;
+  if (all[index].filename == NULL || all[index].function == NULL)
+    {
+      fprintf (stderr, "%s: [%d]: missing file name or function name\n",
+	       name, index);
+      *failed = 1;
+      return;
+    }
+  if (strcmp (base (all[index].filename), want_file) != 0)
+    {
+      fprintf (stderr, "%s: [%d]: got %s expected %s\n", name, index,
+	       all[index].filename, want_file);
+      *failed = 1;
+    }
+  if (all[index].lineno != want_lineno)
+    {
+      fprintf (stderr, "%s: [%d]: got %d expected %d\n", name, index,
+	       all[index].lineno, want_lineno);
+      *failed = 1;
+    }
+  if (strcmp (all[index].function, want_function) != 0)
+    {
+      fprintf (stderr, "%s: [%d]: got %s expected %s\n", name, index,
+	       all[index].function, want_function);
+      *failed = 1;
+    }
+}
+
+/* The backtrace callback function.  */
+
+int
+callback_one (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED,
+	      const char *filename, int lineno, const char *function)
+{
+  struct bdata *data = (struct bdata *) vdata;
+  struct info *p;
+
+  if (data->index >= data->max)
+    {
+      fprintf (stderr, "callback_one: callback called too many times\n");
+      data->failed = 1;
+      return 1;
+    }
+
+  p = &data->all[data->index];
+  if (filename == NULL)
+    p->filename = NULL;
+  else
+    {
+      p->filename = strdup (filename);
+      assert (p->filename != NULL);
+    }
+  p->lineno = lineno;
+  if (function == NULL)
+    p->function = NULL;
+  else
+    {
+      p->function = strdup (function);
+      assert (p->function != NULL);
+    }
+  ++data->index;
+
+  return 0;
+}
+
+/* An error callback passed to backtrace.  */
+
+void
+error_callback_one (void *vdata, const char *msg, int errnum)
+{
+  struct bdata *data = (struct bdata *) vdata;
+
+  fprintf (stderr, "%s", msg);
+  if (errnum > 0)
+    fprintf (stderr, ": %s", strerror (errnum));
+  fprintf (stderr, "\n");
+  data->failed = 1;
+}
+
+/* The backtrace_simple callback function.  */
+
+int
+callback_two (void *vdata, uintptr_t pc)
+{
+  struct sdata *data = (struct sdata *) vdata;
+
+  if (data->index >= data->max)
+    {
+      fprintf (stderr, "callback_two: callback called too many times\n");
+      data->failed = 1;
+      return 1;
+    }
+
+  data->addrs[data->index] = pc;
+  ++data->index;
+
+  return 0;
+}
+
+/* An error callback passed to backtrace_simple.  */
+
+void
+error_callback_two (void *vdata, const char *msg, int errnum)
+{
+  struct sdata *data = (struct sdata *) vdata;
+
+  fprintf (stderr, "%s", msg);
+  if (errnum > 0)
+    fprintf (stderr, ": %s", strerror (errnum));
+  fprintf (stderr, "\n");
+  data->failed = 1;
+}
+
+/* The backtrace_syminfo callback function.  */
+
+void
+callback_three (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED,
+		const char *symname, uintptr_t symval,
+		uintptr_t symsize)
+{
+  struct symdata *data = (struct symdata *) vdata;
+
+  if (symname == NULL)
+    data->name = NULL;
+  else
+    {
+      data->name = strdup (symname);
+      assert (data->name != NULL);
+    }
+  data->val = symval;
+  data->size = symsize;
+}
+
+/* The backtrace_syminfo error callback function.  */
+
+void
+error_callback_three (void *vdata, const char *msg, int errnum)
+{
+  struct symdata *data = (struct symdata *) vdata;
+
+  fprintf (stderr, "%s", msg);
+  if (errnum > 0)
+    fprintf (stderr, ": %s", strerror (errnum));
+  fprintf (stderr, "\n");
+  data->failed = 1;
+}
+
+/* The backtrace_create_state error callback function.  */
+
+void
+error_callback_create (void *data ATTRIBUTE_UNUSED, const char *msg,
+                       int errnum)
+{
+  fprintf (stderr, "%s", msg);
+  if (errnum > 0)
+    fprintf (stderr, ": %s", strerror (errnum));
+  fprintf (stderr, "\n");
+  exit (EXIT_FAILURE);
+}

libbacktrace/testlib.h

@@ -0,0 +1,110 @@
+/* testlib.h -- Header for test functions for libbacktrace library
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#ifndef LIBBACKTRACE_TESTLIB_H
+#define LIBBACKTRACE_TESTLIB_H
+
+/* Portable attribute syntax.  Actually some of these tests probably
+   won't work if the attributes are not recognized.  */
+
+#ifndef GCC_VERSION
+# define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
+#endif
+
+#if (GCC_VERSION < 2007)
+# define __attribute__(x)
+#endif
+
+#ifndef ATTRIBUTE_UNUSED
+# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+#endif
+
+/* Used to collect backtrace info.  */
+
+struct info
+{
+  char *filename;
+  int lineno;
+  char *function;
+};
+
+/* Passed to backtrace callback function.  */
+
+struct bdata
+{
+  struct info *all;
+  size_t index;
+  size_t max;
+  int failed;
+};
+
+/* Passed to backtrace_simple callback function.  */
+
+struct sdata
+{
+  uintptr_t *addrs;
+  size_t index;
+  size_t max;
+  int failed;
+};
+
+/* Passed to backtrace_syminfo callback function.  */
+
+struct symdata
+{
+  const char *name;
+  uintptr_t val, size;
+  int failed;
+};
+
+/* The backtrace state.  */
+
+extern void *state;
+
+/* The number of failures.  */
+
+extern int failures;
+
+extern const char *base (const char *p);
+extern void check (const char *name, int index, const struct info *all,
+		   int want_lineno, const char *want_function,
+		   const char *want_file, int *failed);
+extern int callback_one (void *, uintptr_t, const char *, int, const char *);
+extern void error_callback_one (void *, const char *, int);
+extern int callback_two (void *, uintptr_t);
+extern void error_callback_two (void *, const char *, int);
+extern void callback_three (void *, uintptr_t, const char *, uintptr_t,
+			    uintptr_t);
+extern void error_callback_three (void *, const char *, int);
+extern void error_callback_create (void *, const char *, int);
+
+#endif /* !defined(LIBBACKTRACE_TESTLIB_H) */

libbacktrace/ttest.c

@@ -0,0 +1,161 @@
+/* ttest.c -- Test for libbacktrace library
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+/* Test using the libbacktrace library from multiple threads.  */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <pthread.h>
+
+#include "filenames.h"
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "testlib.h"
+
+static int f2 (int) __attribute__ ((noinline));
+static int f3 (int, int) __attribute__ ((noinline));
+
+/* Test that a simple backtrace works.  This is called via
+   pthread_create.  It returns the number of failures, as void *.  */
+
+static void *
+test1_thread (void *arg ATTRIBUTE_UNUSED)
+{
+  /* Returning a value here and elsewhere avoids a tailcall which
+     would mess up the backtrace.  */
+  return (void *) (uintptr_t) (f2 (__LINE__) - 2);
+}
+
+static int
+f2 (int f1line)
+{
+  return f3 (f1line, __LINE__) + 2;
+}
+
+static int
+f3 (int f1line, int f2line)
+{
+  struct info all[20];
+  struct bdata data;
+  int f3line;
+  int i;
+
+  data.all = &all[0];
+  data.index = 0;
+  data.max = 20;
+  data.failed = 0;
+
+  f3line = __LINE__ + 1;
+  i = backtrace_full (state, 0, callback_one, error_callback_one, &data);
+
+  if (i != 0)
+    {
+      fprintf (stderr, "test1: unexpected return value %d\n", i);
+      data.failed = 1;
+    }
+
+  if (data.index < 3)
+    {
+      fprintf (stderr,
+	       "test1: not enough frames; got %zu, expected at least 3\n",
+	       data.index);
+      data.failed = 1;
+    }
+
+  check ("test1", 0, all, f3line, "f3", "ttest.c", &data.failed);
+  check ("test1", 1, all, f2line, "f2", "ttest.c", &data.failed);
+  check ("test1", 2, all, f1line, "test1_thread", "ttest.c", &data.failed);
+
+  return data.failed;
+}
+
+/* Run the test with 10 threads simultaneously.  */
+
+#define THREAD_COUNT 10
+
+static void test1 (void) __attribute__ ((unused));
+
+static void
+test1 (void)
+{
+  pthread_t atid[THREAD_COUNT];
+  int i;
+  int errnum;
+  int this_fail;
+  void *ret;
+
+  for (i = 0; i < THREAD_COUNT; i++)
+    {
+      errnum = pthread_create (&atid[i], NULL, test1_thread, NULL);
+      if (errnum != 0)
+	{
+	  fprintf (stderr, "pthread_create %d: %s\n", i, strerror (errnum));
+	  exit (EXIT_FAILURE);
+	}
+    }
+
+  this_fail = 0;
+  for (i = 0; i < THREAD_COUNT; i++)
+    {
+      errnum = pthread_join (atid[i], &ret);
+      if (errnum != 0)
+	{
+	  fprintf (stderr, "pthread_join %d: %s\n", i, strerror (errnum));
+	  exit (EXIT_FAILURE);
+	}
+      this_fail += (int) (uintptr_t) ret;
+    }
+
+  printf ("%s: threaded backtrace_full noinline\n", this_fail > 0 ? "FAIL" : "PASS");
+
+  failures += this_fail;
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+#if BACKTRACE_SUPPORTED
+#if BACKTRACE_SUPPORTS_THREADS
+  test1 ();
+#endif
+#endif
+
+  exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/unittest.c

@@ -0,0 +1,92 @@
+/* unittest.c -- Test for libbacktrace library
+   Copyright (C) 2018-2021 Free Software Foundation, Inc.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "filenames.h"
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "testlib.h"
+
+#include "internal.h"
+
+static unsigned count;
+
+static void
+error_callback (void *vdata ATTRIBUTE_UNUSED, const char *msg ATTRIBUTE_UNUSED,
+		int errnum ATTRIBUTE_UNUSED)
+{
+  ++count;
+}
+
+static int
+test1 (void)
+{
+  int res;
+  int failed;
+
+  struct backtrace_vector vec;
+
+  memset (&vec, 0, sizeof vec);
+
+  backtrace_vector_grow (state, 100, error_callback, NULL, &vec);
+  vec.alc += vec.size;
+  vec.size = 0;
+
+  count = 0;
+  res = backtrace_vector_release (state, &vec, error_callback, NULL);
+  failed = res != 1 || count != 0 || vec.base != NULL;
+
+  printf ("%s: unittest backtrace_vector_release size == 0\n",
+	  failed ? "FAIL": "PASS");
+
+  if (failed)
+    ++failures;
+
+  return failures;
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+  test1 ();
+
+  exit (failures ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/unknown.c

@@ -0,0 +1,65 @@
+/* unknown.c -- used when backtrace configury does not know file format.
+   Copyright (C) 2012-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <sys/types.h>
+
+#include "backtrace.h"
+#include "internal.h"
+
+/* A trivial routine that always fails to find fileline data.  */
+
+static int
+unknown_fileline (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		  uintptr_t pc, backtrace_full_callback callback,
+		  backtrace_error_callback error_callback ATTRIBUTE_UNUSED,
+		  void *data)
+
+{
+  return callback (data, pc, NULL, 0, NULL);
+}
+
+/* Initialize the backtrace data when we don't know how to read the
+   debug info.  */
+
+int
+backtrace_initialize (struct backtrace_state *state ATTRIBUTE_UNUSED,
+		      const char *filename ATTRIBUTE_UNUSED,
+		      int descriptor ATTRIBUTE_UNUSED,
+		      backtrace_error_callback error_callback ATTRIBUTE_UNUSED,
+		      void *data ATTRIBUTE_UNUSED, fileline *fileline_fn)
+{
+  state->fileline_data = NULL;
+  *fileline_fn = unknown_fileline;
+  return 1;
+}

libbacktrace/xztest.c

@@ -0,0 +1,508 @@
+/* xztest.c -- Test for libbacktrace LZMA decoder.
+   Copyright (C) 2020-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#ifdef HAVE_LIBLZMA
+#include <lzma.h>
+#endif
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "internal.h"
+#include "testlib.h"
+
+#ifndef HAVE_CLOCK_GETTIME
+
+typedef int xclockid_t;
+
+static int
+xclock_gettime (xclockid_t id ATTRIBUTE_UNUSED,
+		struct timespec *ts ATTRIBUTE_UNUSED)
+{
+  errno = EINVAL;
+  return -1;
+}
+
+#define clockid_t xclockid_t
+#define clock_gettime xclock_gettime
+#undef CLOCK_REALTIME
+#define CLOCK_REALTIME 0
+
+#endif /* !defined(HAVE_CLOCK_GETTIME) */
+
+#ifdef CLOCK_PROCESS_CPUTIME_ID
+#define LIBLZMA_CLOCK_GETTIME_ARG CLOCK_PROCESS_CPUTIME_ID
+#else
+#define LIBLZMA_CLOCK_GETTIME_ARG CLOCK_REALTIME
+#endif
+
+/* Some tests for the local lzma inflation code.  */
+
+struct lzma_test
+{
+  const char *name;
+  const char *uncompressed;
+  size_t uncompressed_len;
+  const char *compressed;
+  size_t compressed_len;
+};
+
+/* Error callback.  */
+
+static void
+error_callback_compress (void *vdata ATTRIBUTE_UNUSED, const char *msg,
+			 int errnum)
+{
+  fprintf (stderr, "%s", msg);
+  if (errnum > 0)
+    fprintf (stderr, ": %s", strerror (errnum));
+  fprintf (stderr, "\n");
+  exit (EXIT_FAILURE);
+}
+
+static const struct lzma_test tests[] =
+{
+  {
+    "empty",
+    "",
+    0,
+    ("\xfd\x37\x7a\x58\x5a\x00\x00\x04\xe6\xd6\xb4\x46\x00\x00\x00\x00"
+     "\x1c\xdf\x44\x21\x1f\xb6\xf3\x7d\x01\x00\x00\x00\x00\x04\x59\x5a"),
+    32,
+  },
+  {
+    "hello",
+    "hello, world\n",
+    0,
+    ("\xfd\x37\x7a\x58\x5a\x00\x00\x04\xe6\xd6\xb4\x46\x02\x00\x21\x01"
+     "\x16\x00\x00\x00\x74\x2f\xe5\xa3\x01\x00\x0c\x68\x65\x6c\x6c\x6f"
+     "\x2c\x20\x77\x6f\x72\x6c\x64\x0a\x00\x00\x00\x00\x7b\x46\x5a\x81"
+     "\xc9\x12\xb8\xea\x00\x01\x25\x0d\x71\x19\xc4\xb6\x1f\xb6\xf3\x7d"
+     "\x01\x00\x00\x00\x00\x04\x59\x5a"),
+    72,
+  },
+  {
+    "goodbye",
+    "goodbye, world",
+    0,
+    ("\xfd\x37\x7a\x58\x5a\x00\x00\x04\xe6\xd6\xb4\x46\x02\x00\x21\x01"
+     "\x16\x00\x00\x00\x74\x2f\xe5\xa3\x01\x00\x0d\x67\x6f\x6f\x64\x62"
+     "\x79\x65\x2c\x20\x77\x6f\x72\x6c\x64\x00\x00\x00\xf6\xf8\xa3\x33"
+     "\x8c\x4e\xc9\x68\x00\x01\x26\x0e\x08\x1b\xe0\x04\x1f\xb6\xf3\x7d"
+     "\x01\x00\x00\x00\x00\x04\x59\x5a"),
+    72,
+  },
+};
+
+/* Test the hand coded samples.  */
+
+static void
+test_samples (struct backtrace_state *state)
+{
+  size_t i;
+
+  for (i = 0; i < sizeof tests / sizeof tests[0]; ++i)
+    {
+      unsigned char *uncompressed;
+      size_t uncompressed_len;
+
+      uncompressed = NULL;
+      uncompressed_len = 0;
+      if (!backtrace_uncompress_lzma (state,
+				      ((const unsigned char *)
+				       tests[i].compressed),
+				      tests[i].compressed_len,
+				      error_callback_compress, NULL,
+				      &uncompressed, &uncompressed_len))
+	{
+	  fprintf (stderr, "test %s: uncompress failed\n", tests[i].name);
+	  ++failures;
+	}
+      else
+	{
+	  size_t v;
+
+	  v = tests[i].uncompressed_len;
+	  if (v == 0)
+	    v = strlen (tests[i].uncompressed);
+	  if (uncompressed_len != v)
+	    {
+	      fprintf (stderr,
+		       "test %s: got uncompressed length %zu, want %zu\n",
+		       tests[i].name, uncompressed_len, v);
+	      ++failures;
+	    }
+	  else if (memcmp (tests[i].uncompressed, uncompressed, v) != 0)
+	    {
+	      size_t j;
+
+	      fprintf (stderr, "test %s: uncompressed data mismatch\n",
+		       tests[i].name);
+	      for (j = 0; j < v; ++j)
+		if (tests[i].uncompressed[j] != uncompressed[j])
+		  fprintf (stderr, "  %zu: got %#x want %#x\n", j,
+			   uncompressed[j], tests[i].uncompressed[j]);
+	      ++failures;
+	    }
+	  else
+	    printf ("PASS: lzma %s\n", tests[i].name);
+
+	  backtrace_free (state, uncompressed, uncompressed_len,
+			  error_callback_compress, NULL);
+	}
+    }
+}
+
+#if HAVE_LIBLZMA
+
+/* Given a set of TRIALS timings, discard the lowest and highest
+   values and return the mean average of the rest.  */
+
+static size_t
+average_time (const size_t *times, size_t trials)
+{
+  size_t imax;
+  size_t max;
+  size_t imin;
+  size_t min;
+  size_t i;
+  size_t sum;
+
+  imin = 0;
+  imax = 0;
+  min = times[0];
+  max = times[0];
+  for (i = 1; i < trials; ++i)
+    {
+      if (times[i] < min)
+	{
+	  imin = i;
+	  min = times[i];
+	}
+      if (times[i] > max)
+	{
+	  imax = i;
+	  max = times[i];
+	}
+    }
+
+  sum = 0;
+  for (i = 0; i < trials; ++i)
+    {
+      if (i != imax && i != imin)
+	sum += times[i];
+    }
+  return sum / (trials - 2);
+}
+
+#endif
+
+/* Test a larger text, if available.  */
+
+static void
+test_large (struct backtrace_state *state ATTRIBUTE_UNUSED)
+{
+#if HAVE_LIBLZMA
+  unsigned char *orig_buf;
+  size_t orig_bufsize;
+  size_t i;
+  lzma_stream initial_stream = LZMA_STREAM_INIT;
+  lzma_stream stream;
+  unsigned char *compressed_buf;
+  size_t compressed_bufsize;
+  unsigned char *uncompressed_buf;
+  size_t uncompressed_bufsize;
+  unsigned char *spare_buf;
+  int r;
+  clockid_t cid;
+  struct timespec ts1;
+  struct timespec ts2;
+  size_t ctime;
+  size_t ztime;
+  const size_t trials = 16;
+  size_t ctimes[16];
+  size_t ztimes[16];
+  static const char * const names[] = {
+    "Isaac.Newton-Opticks.txt",
+    "../libgo/go/testdata/Isaac.Newton-Opticks.txt",
+  };
+
+  orig_buf = NULL;
+  orig_bufsize = 0;
+  uncompressed_buf = NULL;
+  compressed_buf = NULL;
+
+  for (i = 0; i < sizeof names / sizeof names[0]; ++i)
+    {
+      size_t len;
+      char *namebuf;
+      FILE *e;
+      struct stat st;
+      char *rbuf;
+      size_t got;
+
+      len = strlen (SRCDIR) + strlen (names[i]) + 2;
+      namebuf = malloc (len);
+      if (namebuf == NULL)
+	{
+	  perror ("malloc");
+	  goto fail;
+	}
+      snprintf (namebuf, len, "%s/%s", SRCDIR, names[i]);
+      e = fopen (namebuf, "r");
+      free (namebuf);
+      if (e == NULL)
+	continue;
+      if (fstat (fileno (e), &st) < 0)
+	{
+	  perror ("fstat");
+	  fclose (e);
+	  continue;
+	}
+      rbuf = malloc (st.st_size);
+      if (rbuf == NULL)
+	{
+	  perror ("malloc");
+	  goto fail;
+	}
+      got = fread (rbuf, 1, st.st_size, e);
+      fclose (e);
+      if (got > 0)
+	{
+	  orig_buf = (unsigned char *) rbuf;
+	  orig_bufsize = got;
+	  break;
+	}
+      free (rbuf);
+    }
+
+  if (orig_buf == NULL)
+    {
+      /* We couldn't find an input file.  */
+      printf ("UNSUPPORTED: lzma large\n");
+      return;
+    }
+
+  stream = initial_stream;
+  r =  lzma_easy_encoder (&stream, 6, LZMA_CHECK_CRC32);
+  if (r != LZMA_OK)
+    {
+      fprintf (stderr, "lzma_easy_encoder failed: %d\n", r);
+      goto fail;
+    }
+
+  compressed_bufsize = orig_bufsize + 100;
+  compressed_buf = malloc (compressed_bufsize);
+  if (compressed_buf == NULL)
+    {
+      perror ("malloc");
+      goto fail;
+    }
+
+  stream.next_in = orig_buf;
+  stream.avail_in = orig_bufsize;
+  stream.next_out = compressed_buf;
+  stream.avail_out = compressed_bufsize;
+
+  do
+    {
+      r = lzma_code (&stream, LZMA_FINISH);
+      if (r != LZMA_OK && r != LZMA_STREAM_END)
+	{
+	  fprintf (stderr, "lzma_code failed: %d\n", r);
+	  goto fail;
+	}
+    }
+  while (r != LZMA_STREAM_END);
+
+  compressed_bufsize = stream.total_out;
+
+  if (!backtrace_uncompress_lzma (state, (unsigned char *) compressed_buf,
+				  compressed_bufsize,
+				  error_callback_compress, NULL,
+				  &uncompressed_buf, &uncompressed_bufsize))
+    {
+      fprintf (stderr, "lzma large: backtrace_uncompress_lzma failed\n");
+      goto fail;
+    }
+
+  if (uncompressed_bufsize != orig_bufsize)
+    {
+      fprintf (stderr,
+	       "lzma large: got uncompressed length %zu, want %zu\n",
+	       uncompressed_bufsize, orig_bufsize);
+      goto fail;
+    }
+
+  if (memcmp (uncompressed_buf, orig_buf, uncompressed_bufsize) != 0)
+    {
+      fprintf (stderr, "lzma large: uncompressed data mismatch\n");
+      goto fail;
+    }
+
+  printf ("PASS: lzma large\n");
+
+  spare_buf = malloc (orig_bufsize);
+  if (spare_buf == NULL)
+    {
+      perror ("malloc");
+      goto fail;
+    }
+
+  for (i = 0; i < trials; ++i)
+    {
+      cid = LIBLZMA_CLOCK_GETTIME_ARG;
+      if (clock_gettime (cid, &ts1) < 0)
+	{
+	  if (errno == EINVAL)
+	    return;
+	  perror ("clock_gettime");
+	  return;
+	}
+
+      if (!backtrace_uncompress_lzma (state,
+				      (unsigned char *) compressed_buf,
+				      compressed_bufsize,
+				      error_callback_compress, NULL,
+				      &uncompressed_buf,
+				      &uncompressed_bufsize))
+	{
+	  fprintf (stderr,
+		   ("lzma large: "
+		    "benchmark backtrace_uncompress_lzma failed\n"));
+	  return;
+	}
+
+      if (clock_gettime (cid, &ts2) < 0)
+	{
+	  perror ("clock_gettime");
+	  return;
+	}
+
+      ctime = (ts2.tv_sec - ts1.tv_sec) * 1000000000;
+      ctime += ts2.tv_nsec - ts1.tv_nsec;
+      ctimes[i] = ctime;
+
+      stream = initial_stream;
+
+      r = lzma_auto_decoder (&stream, UINT64_MAX, 0);
+      if (r != LZMA_OK)
+	{
+	  fprintf (stderr, "lzma_stream_decoder failed: %d\n", r);
+	  goto fail;
+	}
+
+      stream.next_in = compressed_buf;
+      stream.avail_in = compressed_bufsize;
+      stream.next_out = spare_buf;
+      stream.avail_out = orig_bufsize;
+
+      if (clock_gettime (cid, &ts1) < 0)
+	{
+	  perror("clock_gettime");
+	  return;
+	}
+
+      do
+	{
+	  r = lzma_code (&stream, LZMA_FINISH);
+	  if (r != LZMA_OK && r != LZMA_STREAM_END)
+	    {
+	      fprintf (stderr, "lzma_code failed: %d\n", r);
+	      goto fail;
+	    }
+	}
+      while (r != LZMA_STREAM_END);
+
+      if (clock_gettime (cid, &ts2) < 0)
+	{
+	  perror ("clock_gettime");
+	  return;
+	}
+
+      ztime = (ts2.tv_sec - ts1.tv_sec) * 1000000000;
+      ztime += ts2.tv_nsec - ts1.tv_nsec;
+      ztimes[i] = ztime;
+    }
+
+  /* Toss the highest and lowest times and average the rest.  */
+  ctime = average_time (ctimes, trials);
+  ztime = average_time (ztimes, trials);
+
+  printf ("backtrace: %zu ns\n", ctime);
+  printf ("liblzma  : %zu ns\n", ztime);
+  printf ("ratio    : %g\n", (double) ztime / (double) ctime);
+
+  return;
+
+ fail:
+  printf ("FAIL: lzma large\n");
+  ++failures;
+
+  if (orig_buf != NULL)
+    free (orig_buf);
+  if (compressed_buf != NULL)
+    free (compressed_buf);
+  if (uncompressed_buf != NULL)
+    free (uncompressed_buf);
+
+#else /* !HAVE_LIBLZMA */
+
+ printf ("UNSUPPORTED: lzma large\n");
+
+#endif /* !HAVE_LIBLZMA */
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  struct backtrace_state *state;
+
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+  test_samples (state);
+  test_large (state);
+
+  exit (failures != 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+}

libbacktrace/ztest.c

@@ -0,0 +1,541 @@
+/* ztest.c -- Test for libbacktrace inflate code.
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
+   Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    (1) Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    (2) Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    (3) The name of the author may not be used to
+    endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.  */
+
+#include "config.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#ifdef HAVE_ZLIB
+#include <zlib.h>
+#endif
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+
+#include "internal.h"
+#include "testlib.h"
+
+#ifndef HAVE_CLOCK_GETTIME
+
+typedef int xclockid_t;
+
+static int
+xclock_gettime (xclockid_t id ATTRIBUTE_UNUSED,
+		struct timespec *ts ATTRIBUTE_UNUSED)
+{
+  errno = EINVAL;
+  return -1;
+}
+
+#define clockid_t xclockid_t
+#define clock_gettime xclock_gettime
+#undef CLOCK_REALTIME
+#define CLOCK_REALTIME 0
+
+#endif /* !defined(HAVE_CLOCK_GETTIME) */
+
+#ifdef CLOCK_PROCESS_CPUTIME_ID
+#define ZLIB_CLOCK_GETTIME_ARG CLOCK_PROCESS_CPUTIME_ID
+#else
+#define ZLIB_CLOCK_GETTIME_ARG CLOCK_REALTIME
+#endif
+
+/* Some tests for the local zlib inflation code.  */
+
+struct zlib_test
+{
+  const char *name;
+  const char *uncompressed;
+  size_t uncompressed_len;
+  const char *compressed;
+  size_t compressed_len;
+};
+
+/* Error callback.  */
+
+static void
+error_callback_compress (void *vdata ATTRIBUTE_UNUSED, const char *msg,
+			 int errnum)
+{
+  fprintf (stderr, "%s", msg);
+  if (errnum > 0)
+    fprintf (stderr, ": %s", strerror (errnum));
+  fprintf (stderr, "\n");
+  exit (EXIT_FAILURE);
+}
+
+static const struct zlib_test tests[] =
+{
+  {
+    "empty",
+    "",
+    0,
+    "\x78\x9c\x03\x00\x00\x00\x00\x01",
+    8,
+  },
+  {
+    "hello",
+    "hello, world\n",
+    0,
+    ("\x78\x9c\xca\x48\xcd\xc9\xc9\xd7\x51\x28\xcf"
+     "\x2f\xca\x49\xe1\x02\x04\x00\x00\xff\xff\x21\xe7\x04\x93"),
+    25,
+  },
+  {
+    "goodbye",
+    "goodbye, world",
+    0,
+    ("\x78\x9c\x4b\xcf\xcf\x4f\x49\xaa"
+     "\x4c\xd5\x51\x28\xcf\x2f\xca\x49"
+     "\x01\x00\x28\xa5\x05\x5e"),
+    22,
+  },
+  {
+    "ranges",
+    ("\xcc\x11\x00\x00\x00\x00\x00\x00\xd5\x13\x00\x00\x00\x00\x00\x00"
+     "\x1c\x14\x00\x00\x00\x00\x00\x00\x72\x14\x00\x00\x00\x00\x00\x00"
+     "\x9d\x14\x00\x00\x00\x00\x00\x00\xd5\x14\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\xfb\x12\x00\x00\x00\x00\x00\x00\x09\x13\x00\x00\x00\x00\x00\x00"
+     "\x0c\x13\x00\x00\x00\x00\x00\x00\xcb\x13\x00\x00\x00\x00\x00\x00"
+     "\x29\x14\x00\x00\x00\x00\x00\x00\x4e\x14\x00\x00\x00\x00\x00\x00"
+     "\x9d\x14\x00\x00\x00\x00\x00\x00\xd5\x14\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\xfb\x12\x00\x00\x00\x00\x00\x00\x09\x13\x00\x00\x00\x00\x00\x00"
+     "\x67\x13\x00\x00\x00\x00\x00\x00\xcb\x13\x00\x00\x00\x00\x00\x00"
+     "\x9d\x14\x00\x00\x00\x00\x00\x00\xd5\x14\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\x5f\x0b\x00\x00\x00\x00\x00\x00\x6c\x0b\x00\x00\x00\x00\x00\x00"
+     "\x7d\x0b\x00\x00\x00\x00\x00\x00\x7e\x0c\x00\x00\x00\x00\x00\x00"
+     "\x38\x0f\x00\x00\x00\x00\x00\x00\x5c\x0f\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\x83\x0c\x00\x00\x00\x00\x00\x00\xfa\x0c\x00\x00\x00\x00\x00\x00"
+     "\xfd\x0d\x00\x00\x00\x00\x00\x00\xef\x0e\x00\x00\x00\x00\x00\x00"
+     "\x14\x0f\x00\x00\x00\x00\x00\x00\x38\x0f\x00\x00\x00\x00\x00\x00"
+     "\x9f\x0f\x00\x00\x00\x00\x00\x00\xac\x0f\x00\x00\x00\x00\x00\x00"
+     "\xdb\x0f\x00\x00\x00\x00\x00\x00\xff\x0f\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\xfd\x0d\x00\x00\x00\x00\x00\x00\xd8\x0e\x00\x00\x00\x00\x00\x00"
+     "\x9f\x0f\x00\x00\x00\x00\x00\x00\xac\x0f\x00\x00\x00\x00\x00\x00"
+     "\xdb\x0f\x00\x00\x00\x00\x00\x00\xff\x0f\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\xfa\x0c\x00\x00\x00\x00\x00\x00\xea\x0d\x00\x00\x00\x00\x00\x00"
+     "\xef\x0e\x00\x00\x00\x00\x00\x00\x14\x0f\x00\x00\x00\x00\x00\x00"
+     "\x5c\x0f\x00\x00\x00\x00\x00\x00\x9f\x0f\x00\x00\x00\x00\x00\x00"
+     "\xac\x0f\x00\x00\x00\x00\x00\x00\xdb\x0f\x00\x00\x00\x00\x00\x00"
+     "\xff\x0f\x00\x00\x00\x00\x00\x00\x2c\x10\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\x60\x11\x00\x00\x00\x00\x00\x00\xd1\x16\x00\x00\x00\x00\x00\x00"
+     "\x40\x0b\x00\x00\x00\x00\x00\x00\x2c\x10\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\x7a\x00\x00\x00\x00\x00\x00\x00\xb6\x00\x00\x00\x00\x00\x00\x00"
+     "\x9f\x01\x00\x00\x00\x00\x00\x00\xa7\x01\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
+     "\x7a\x00\x00\x00\x00\x00\x00\x00\xa9\x00\x00\x00\x00\x00\x00\x00"
+     "\x9f\x01\x00\x00\x00\x00\x00\x00\xa7\x01\x00\x00\x00\x00\x00\x00"
+     "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"),
+    672,
+    ("\x78\x9c\x3b\x23\xc8\x00\x06\x57\x85\x21\xb4\x8c\x08\x84\x2e\x82"
+     "\xd2\x73\xa1\xf4\x55\x28\x8d\x0e\x7e\x0b\x41\x68\x4e\xa8\x7e\x1e"
+     "\x28\x7d\x1a\x4a\x6b\x42\xf5\xf9\x91\x69\x5e\x3a\x9a\x79\x84\xf4"
+     "\xc7\x73\x43\xe8\x1c\x28\x5d\x0b\xa5\xeb\x78\x20\xb4\x05\x3f\x84"
+     "\x8e\xe1\xc7\xae\xbf\x19\xaa\xee\x17\x94\xfe\xcb\x0b\xa1\xdf\xf3"
+     "\x41\x68\x11\x7e\x54\x73\xe6\x43\xe9\x35\x50\xfa\x36\x94\xfe\x8f"
+     "\xc3\x7c\x98\x79\x37\xf8\xc8\xd3\x0f\x73\xd7\x2b\x1c\xee\x8a\x21"
+     "\xd2\x5d\x3a\x02\xd8\xcd\x4f\x80\xa6\x87\x8b\x62\x10\xda\x81\x1b"
+     "\xbf\xfa\x2a\x28\xbd\x0d\x4a\xcf\x67\x84\xd0\xcb\x19\xf1\xab\x5f"
+     "\x49\xa4\x7a\x00\x48\x97\x29\xd4"),
+    152,
+  }
+};
+
+/* Test the hand coded samples.  */
+
+static void
+test_samples (struct backtrace_state *state)
+{
+  size_t i;
+
+  for (i = 0; i < sizeof tests / sizeof tests[0]; ++i)
+    {
+      char *p;
+      size_t v;
+      size_t j;
+      unsigned char *uncompressed;
+      size_t uncompressed_len;
+
+      p = malloc (12 + tests[i].compressed_len);
+      memcpy (p, "ZLIB", 4);
+      v = tests[i].uncompressed_len;
+      if (v == 0)
+	v = strlen (tests[i].uncompressed);
+      for (j = 0; j < 8; ++j)
+	p[j + 4] = (v >> ((7 - j) * 8)) & 0xff;
+      memcpy (p + 12, tests[i].compressed, tests[i].compressed_len);
+      uncompressed = NULL;
+      uncompressed_len = 0;
+      if (!backtrace_uncompress_zdebug (state, (unsigned char *) p,
+					tests[i].compressed_len + 12,
+					error_callback_compress, NULL,
+					&uncompressed, &uncompressed_len))
+	{
+	  fprintf (stderr, "test %s: uncompress failed\n", tests[i].name);
+	  ++failures;
+	}
+      else
+	{
+	  if (uncompressed_len != v)
+	    {
+	      fprintf (stderr,
+		       "test %s: got uncompressed length %zu, want %zu\n",
+		       tests[i].name, uncompressed_len, v);
+	      ++failures;
+	    }
+	  else if (memcmp (tests[i].uncompressed, uncompressed, v) != 0)
+	    {
+	      size_t j;
+
+	      fprintf (stderr, "test %s: uncompressed data mismatch\n",
+		       tests[i].name);
+	      for (j = 0; j < v; ++j)
+		if (tests[i].uncompressed[j] != uncompressed[j])
+		  fprintf (stderr, "  %zu: got %#x want %#x\n", j,
+			   uncompressed[j], tests[i].uncompressed[j]);
+	      ++failures;
+	    }
+	  else
+	    printf ("PASS: inflate %s\n", tests[i].name);
+
+	  backtrace_free (state, uncompressed, uncompressed_len,
+			  error_callback_compress, NULL);
+	}
+    }
+}
+
+#ifdef HAVE_ZLIB
+
+/* Given a set of TRIALS timings, discard the lowest and highest
+   values and return the mean average of the rest.  */
+
+static size_t
+average_time (const size_t *times, size_t trials)
+{
+  size_t imax;
+  size_t max;
+  size_t imin;
+  size_t min;
+  size_t i;
+  size_t sum;
+
+  imin = 0;
+  imax = 0;
+  min = times[0];
+  max = times[0];
+  for (i = 1; i < trials; ++i)
+    {
+      if (times[i] < min)
+	{
+	  imin = i;
+	  min = times[i];
+	}
+      if (times[i] > max)
+	{
+	  imax = i;
+	  max = times[i];
+	}
+    }
+
+  sum = 0;
+  for (i = 0; i < trials; ++i)
+    {
+      if (i != imax && i != imin)
+	sum += times[i];
+    }
+  return sum / (trials - 2);
+}
+
+#endif
+
+/* Test a larger text, if available.  */
+
+static void
+test_large (struct backtrace_state *state ATTRIBUTE_UNUSED)
+{
+#ifdef HAVE_ZLIB
+  unsigned char *orig_buf;
+  size_t orig_bufsize;
+  size_t i;
+  char *compressed_buf;
+  size_t compressed_bufsize;
+  unsigned long compress_sizearg;
+  unsigned char *uncompressed_buf;
+  size_t uncompressed_bufsize;
+  int r;
+  clockid_t cid;
+  struct timespec ts1;
+  struct timespec ts2;
+  size_t ctime;
+  size_t ztime;
+  const size_t trials = 16;
+  size_t ctimes[16];
+  size_t ztimes[16];
+  static const char * const names[] = {
+    "Isaac.Newton-Opticks.txt",
+    "../libgo/go/testdata/Isaac.Newton-Opticks.txt",
+  };
+
+  orig_buf = NULL;
+  orig_bufsize = 0;
+  uncompressed_buf = NULL;
+  compressed_buf = NULL;
+
+  for (i = 0; i < sizeof names / sizeof names[0]; ++i)
+    {
+      size_t len;
+      char *namebuf;
+      FILE *e;
+      struct stat st;
+      char *rbuf;
+      size_t got;
+
+      len = strlen (SRCDIR) + strlen (names[i]) + 2;
+      namebuf = malloc (len);
+      if (namebuf == NULL)
+	{
+	  perror ("malloc");
+	  goto fail;
+	}
+      snprintf (namebuf, len, "%s/%s", SRCDIR, names[i]);
+      e = fopen (namebuf, "r");
+      free (namebuf);
+      if (e == NULL)
+	continue;
+      if (fstat (fileno (e), &st) < 0)
+	{
+	  perror ("fstat");
+	  fclose (e);
+	  continue;
+	}
+      rbuf = malloc (st.st_size);
+      if (rbuf == NULL)
+	{
+	  perror ("malloc");
+	  goto fail;
+	}
+      got = fread (rbuf, 1, st.st_size, e);
+      fclose (e);
+      if (got > 0)
+	{
+	  orig_buf = (unsigned char *) rbuf;
+	  orig_bufsize = got;
+	  break;
+	}
+      free (rbuf);
+    }
+
+  if (orig_buf == NULL)
+    {
+      /* We couldn't find an input file.  */
+      printf ("UNSUPPORTED: inflate large\n");
+      return;
+    }
+
+  compressed_bufsize = compressBound (orig_bufsize) + 12;
+  compressed_buf = malloc (compressed_bufsize);
+  if (compressed_buf == NULL)
+    {
+      perror ("malloc");
+      goto fail;
+    }
+
+  compress_sizearg = compressed_bufsize - 12;
+  r = compress ((unsigned char *) compressed_buf + 12, &compress_sizearg,
+		orig_buf, orig_bufsize);
+  if (r != Z_OK)
+    {
+      fprintf (stderr, "zlib compress failed: %d\n", r);
+      goto fail;
+    }
+
+  compressed_bufsize = compress_sizearg + 12;
+
+  /* Prepare the header that our library expects.  */
+  memcpy (compressed_buf, "ZLIB", 4);
+  for (i = 0; i < 8; ++i)
+    compressed_buf[i + 4] = (orig_bufsize >> ((7 - i) * 8)) & 0xff;
+
+  uncompressed_buf = malloc (orig_bufsize);
+  if (uncompressed_buf == NULL)
+    {
+      perror ("malloc");
+      goto fail;
+    }
+  uncompressed_bufsize = orig_bufsize;
+
+  if (!backtrace_uncompress_zdebug (state, (unsigned char *) compressed_buf,
+				    compressed_bufsize,
+				    error_callback_compress, NULL,
+				    &uncompressed_buf, &uncompressed_bufsize))
+    {
+      fprintf (stderr, "inflate large: backtrace_uncompress_zdebug failed\n");
+      goto fail;
+    }
+
+  if (uncompressed_bufsize != orig_bufsize)
+    {
+      fprintf (stderr,
+	       "inflate large: got uncompressed length %zu, want %zu\n",
+	       uncompressed_bufsize, orig_bufsize);
+      goto fail;
+    }
+
+  if (memcmp (uncompressed_buf, orig_buf, uncompressed_bufsize) != 0)
+    {
+      fprintf (stderr, "inflate large: uncompressed data mismatch\n");
+      goto fail;
+    }
+
+  printf ("PASS: inflate large\n");
+
+  for (i = 0; i < trials; ++i)
+    {
+      unsigned long uncompress_sizearg;
+
+      cid = ZLIB_CLOCK_GETTIME_ARG;
+      if (clock_gettime (cid, &ts1) < 0)
+	{
+	  if (errno == EINVAL)
+	    return;
+	  perror ("clock_gettime");
+	  return;
+	}
+
+      if (!backtrace_uncompress_zdebug (state,
+					(unsigned char *) compressed_buf,
+					compressed_bufsize,
+					error_callback_compress, NULL,
+					&uncompressed_buf,
+					&uncompressed_bufsize))
+	{
+	  fprintf (stderr,
+		   ("inflate large: "
+		    "benchmark backtrace_uncompress_zdebug failed\n"));
+	  return;
+	}
+
+      if (clock_gettime (cid, &ts2) < 0)
+	{
+	  perror ("clock_gettime");
+	  return;
+	}
+
+      ctime = (ts2.tv_sec - ts1.tv_sec) * 1000000000;
+      ctime += ts2.tv_nsec - ts1.tv_nsec;
+      ctimes[i] = ctime;
+
+      if (clock_gettime (cid, &ts1) < 0)
+	{
+	  perror("clock_gettime");
+	  return;
+	}
+
+      uncompress_sizearg = uncompressed_bufsize;
+      r = uncompress ((unsigned char *) uncompressed_buf, &uncompress_sizearg,
+		      (unsigned char *) compressed_buf + 12,
+		      compressed_bufsize - 12);
+
+      if (clock_gettime (cid, &ts2) < 0)
+	{
+	  perror ("clock_gettime");
+	  return;
+	}
+
+      if (r != Z_OK)
+	{
+	  fprintf (stderr,
+		   "inflate large: benchmark zlib uncompress failed: %d\n",
+		   r);
+	  return;
+	}
+
+      ztime = (ts2.tv_sec - ts1.tv_sec) * 1000000000;
+      ztime += ts2.tv_nsec - ts1.tv_nsec;
+      ztimes[i] = ztime;
+    }
+
+  /* Toss the highest and lowest times and average the rest.  */
+  ctime = average_time (ctimes, trials);
+  ztime = average_time (ztimes, trials);
+
+  printf ("backtrace: %zu ns\n", ctime);
+  printf ("zlib     : %zu ns\n", ztime);
+  printf ("ratio    : %g\n", (double) ztime / (double) ctime);
+
+  return;
+
+ fail:
+  printf ("FAIL: inflate large\n");
+  ++failures;
+
+  if (orig_buf != NULL)
+    free (orig_buf);
+  if (compressed_buf != NULL)
+    free (compressed_buf);
+  if (uncompressed_buf != NULL)
+    free (uncompressed_buf);
+
+#else /* !HAVE_ZLIB */
+
+ printf ("UNSUPPORTED: inflate large\n");
+
+#endif /* !HAVE_ZLIB */
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+  struct backtrace_state *state;
+
+  state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+				  error_callback_create, NULL);
+
+  test_samples (state);
+  test_large (state);
+
+  exit (failures != 0 ? EXIT_FAILURE : EXIT_SUCCESS);
+}