sim: formally assume unistd.h always exists (via gnulib)

We have many uses of unistd.h that are unprotected by HAVE_UNISTD_H,
so this is more formalizing the reality that we require this header.
Since we switched to gnulib, it guarantees that a unistd.h exists
for us to include, so we're doubly OK.

sim/arm/armos.c

@@ -31,10 +31,7 @@
 #include <errno.h>
 #include <limits.h>
 #include <string.h>
-
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>		/* For SEEK_SET etc.  */
-#endif
 
 #include "armdefs.h"
 #include "armos.h"

sim/common/callback.c

@@ -34,9 +34,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <sys/stat.h>
 #include <sys/types.h>
 

sim/common/dv-pal.c

@@ -24,9 +24,7 @@
 
 #include <stdlib.h>
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 
 #include "sim-main.h"
 #include "hw-main.h"

sim/common/dv-sockser.c

@@ -29,9 +29,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <signal.h>
 #include <stdlib.h>
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <arpa/inet.h>
 #include <netinet/in.h>
 #include <sys/select.h>

sim/common/nrun.c

@@ -21,10 +21,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <stdlib.h>
 /* For strsignal.  */
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 /* For chdir.  */
 #include <unistd.h>
-#endif
 
 #include "bfd.h"
 #include "environ.h"

sim/common/sim-io.c

@@ -29,9 +29,7 @@
 #include <stdarg.h>
 #include <stdint.h>
 #include <stdlib.h>
-#if HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 
 #undef open
 

sim/common/sim-memopt.c

@@ -26,9 +26,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #endif
 #include <stdlib.h>
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #ifdef HAVE_SYS_MMAN_H
 #include <sys/mman.h>
 #endif

sim/common/syscall.c

@@ -33,9 +33,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <sys/stat.h>
 #include <sys/types.h>
 

sim/configure

@@ -2797,7 +2797,6 @@ as_fn_append ac_header_list " dlfcn.h"
 as_fn_append ac_header_list " fcntl.h"
 as_fn_append ac_header_list " fpu_control.h"
 as_fn_append ac_header_list " termios.h"
-as_fn_append ac_header_list " unistd.h"
 as_fn_append ac_header_list " utime.h"
 as_fn_append ac_header_list " linux/if_tun.h"
 as_fn_append ac_header_list " linux/mii.h"
@@ -5265,8 +5264,6 @@ done
 
 
 
-
-
 
 
 
@@ -12289,7 +12286,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12292 "configure"
+#line 12289 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12395,7 +12392,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 12398 "configure"
+#line 12395 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H

sim/cr16/simops.c

@@ -24,9 +24,7 @@
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/stat.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <string.h>
 #include <time.h>
 #include <sys/time.h>

sim/cris/dv-rv.c

@@ -29,9 +29,7 @@
 #include <ctype.h>
 #include <errno.h>
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>

sim/cris/rvdummy.c

@@ -36,10 +36,7 @@ main (int argc, char *argv[])
 #include "libiberty.h"
 
 #include <stdio.h>
-
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 #include <string.h>
 #ifdef HAVE_SYS_TYPES_H

sim/cris/traps.c

@@ -32,9 +32,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <stdlib.h>
 #include <stdarg.h>
 #include <errno.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #ifdef HAVE_FCNTL_H
 #include <fcntl.h>
 #endif

sim/d10v/simops.c

@@ -5,9 +5,7 @@
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/stat.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <string.h>
 
 #include "bfd.h"

sim/m4/sim_ac_platform.m4

@@ -18,12 +18,12 @@ AC_DEFUN([SIM_AC_PLATFORM],
 [dnl
 dnl Check for common headers.
 dnl NB: You can assume C11 headers exist.
+dnl NB: We use gnulib from ../gnulib/, so we don't probe headers it provides.
 AC_CHECK_HEADERS_ONCE(m4_flatten([
   dlfcn.h
   fcntl.h
   fpu_control.h
   termios.h
-  unistd.h
   utime.h
   linux/if_tun.h
   linux/mii.h
@@ -46,6 +46,7 @@ AC_CHECK_HEADERS_ONCE(m4_flatten([
 ]))
 AC_HEADER_DIRENT
 
+dnl NB: We use gnulib from ../gnulib/, so we don't probe functions it provides.
 AC_CHECK_FUNCS_ONCE(m4_flatten([
   __setfpucw
   access

sim/m68hc11/emulos.c

@@ -21,9 +21,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "defs.h"
 
 #include "sim-main.h"
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 
 #include "m68hc11-sim.h"
 

sim/mn10300/op_utils.c

@@ -3,9 +3,7 @@
 
 #include <errno.h>
 #include <time.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <string.h>
 #include <sys/stat.h>
 #include <sys/time.h>

sim/ppc/emul_bugapi.c

@@ -27,9 +27,7 @@
 #include "emul_generic.h"
 #include "emul_bugapi.h"
 
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 #include <string.h>
 

sim/ppc/emul_chirp.c

@@ -28,9 +28,7 @@
 #include "emul_chirp.h"
 
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 
 #ifndef STATIC_INLINE_EMUL_CHIRP
 #define STATIC_INLINE_EMUL_CHIRP STATIC_INLINE

sim/ppc/emul_netbsd.c

@@ -72,10 +72,8 @@ int getrusage();
 # endif
 #endif
 
-#ifdef HAVE_UNISTD_H
 #undef MAXPATHLEN		/* sys/param.h might define this also */
 #include <unistd.h>
-#endif
 
 #include <stdlib.h>
 

sim/ppc/emul_unix.c

@@ -115,10 +115,8 @@ int getrusage();
 # endif
 #endif
 
-#ifdef HAVE_UNISTD_H
 #undef MAXPATHLEN		/* sys/param.h might define this also */
 #include <unistd.h>
-#endif
 
 #include <stdlib.h>
 #include <time.h>

sim/ppc/hw_com.c

@@ -28,9 +28,7 @@
 #include "device_table.h"
 
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 
 /* DEVICE

sim/ppc/hw_disk.c

@@ -26,10 +26,7 @@
 #include "pk.h"
 
 #include <stdio.h>
-
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 
 #ifndef	SEEK_SET
 #define	SEEK_SET 0

sim/ppc/hw_pal.c

@@ -30,9 +30,7 @@
 #include "cpu.h"
 
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 
 

sim/ppc/main.c

@@ -36,9 +36,7 @@
 #include "sim/sim.h"
 
 #include <stdlib.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <string.h>
 #include <errno.h>
 

sim/ppc/mon.c

@@ -26,9 +26,7 @@
 #include <stdio.h>
 
 #include <string.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>

sim/ppc/table.c

@@ -29,9 +29,7 @@
 #include "lf.h"
 #include "table.h"
 
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 
 typedef struct _open_table open_table;

sim/rl78/main.c

@@ -25,9 +25,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <assert.h>
 #include <setjmp.h>
 #include <signal.h>

sim/rx/main.c

@@ -24,9 +24,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <assert.h>
 #include <setjmp.h>
 #include <signal.h>

sim/sh/interp.c

@@ -25,9 +25,7 @@
 #include <stdio.h>
 #include <errno.h>
 #include <signal.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #ifdef HAVE_MMAP
 #include <sys/mman.h>
 # ifndef MAP_FAILED

sim/v850/simops.c

@@ -12,9 +12,7 @@
 #include <utime.h>
 #endif
 #include <time.h>
-#ifdef HAVE_UNISTD_H
 #include <unistd.h>
-#endif
 #include <stdlib.h>
 #include <string.h>