From 8de432b726c8441b9516df3c156f42cdc39fa1bf Mon Sep 17 00:00:00 2001
From: Mark Poliakov <mark@alnyan.me>
Date: Fri, 5 Nov 2021 13:50:00 +0200
Subject: [PATCH] refactor: add clippy to init/libusr

---
 Makefile             |  3 +++
 libusr/src/io.rs     |  5 ++++-
 libusr/src/mem.rs    | 38 ++++++++++++++++++++++++++++++++++++++
 syscall/src/calls.rs | 32 +++++++++++++++++++++++++++++++-
 4 files changed, 76 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 3309c5b..b124ef1 100644
--- a/Makefile
+++ b/Makefile
@@ -121,6 +121,9 @@ doc-open:
 
 clippy:
 	cd kernel && cargo clippy $(CARGO_BUILD_OPTS)
+	cd init && cargo clippy \
+		--target=../etc/$(ARCH)-osdev5.json \
+		-Zbuild-std=core,alloc,compiler_builtins $(CARGO_COMMON_OPTS)
 
 qemu: all
 	$(QEMU_PREFIX)qemu-system-$(ARCH) $(QEMU_OPTS)
diff --git a/libusr/src/io.rs b/libusr/src/io.rs
index 58bbe14..ce90b74 100644
--- a/libusr/src/io.rs
+++ b/libusr/src/io.rs
@@ -2,7 +2,10 @@ use crate::sys::{self, Stat};
 use syscall::stat::AT_FDCWD;
 use core::fmt;
 
-pub fn stat(pathname: &str) -> Result<Stat, ()> {
+// TODO populate this type
+pub struct Error;
+
+pub fn stat(pathname: &str) -> Result<Stat, Error> {
     let mut buf = Stat::default();
     let res = unsafe {
         sys::sys_fstatat(AT_FDCWD, pathname, &mut buf, 0)
diff --git a/libusr/src/mem.rs b/libusr/src/mem.rs
index 6d667be..1b9f19a 100644
--- a/libusr/src/mem.rs
+++ b/libusr/src/mem.rs
@@ -1,3 +1,9 @@
+/// See memcpy(3p).
+///
+/// # Safety
+///
+/// Unsafe: writes to arbitrary memory locations, performs no pointer
+/// validation.
 #[no_mangle]
 pub unsafe extern "C" fn memcpy(dst: *mut u8, src: *mut u8, mut len: usize) -> *mut u8 {
     while len != 0 {
@@ -7,6 +13,12 @@ pub unsafe extern "C" fn memcpy(dst: *mut u8, src: *mut u8, mut len: usize) -> *
     dst
 }
 
+/// See memcmp(3p).
+///
+/// # Safety
+///
+/// Unsafe: performs reads from arbitrary memory locations, performs no
+/// pointer validation.
 #[no_mangle]
 pub unsafe extern "C" fn memcmp(a: *mut u8, b: *mut u8, mut len: usize) -> isize {
     while len != 0 {
@@ -21,6 +33,32 @@ pub unsafe extern "C" fn memcmp(a: *mut u8, b: *mut u8, mut len: usize) -> isize
     0
 }
 
+/// See memmove(3p)
+///
+/// # Safety
+///
+/// Unsafe: writes to arbitrary memory locations, performs no pointer
+/// validation.
+#[no_mangle]
+pub unsafe extern "C" fn memmove(dst: *mut u8, src: *mut u8, len: usize) -> *mut u8 {
+    if dst < src {
+        for i in 0..len {
+            *dst.add(i) = *src.add(i);
+        }
+    } else {
+        for i in 0..len {
+            *dst.add(len - (i + 1)) = *src.add(len - (i + 1));
+        }
+    }
+    dst
+}
+
+/// See memset(3p)
+///
+/// # Safety
+///
+/// Unsafe: writes to arbitrary memory locations, performs no pointer
+/// validation.
 #[no_mangle]
 pub unsafe extern "C" fn memset(buf: *mut u8, val: u8, mut len: usize) -> *mut u8 {
     while len != 0 {
diff --git a/syscall/src/calls.rs b/syscall/src/calls.rs
index bd30e0f..7494c3e 100644
--- a/syscall/src/calls.rs
+++ b/syscall/src/calls.rs
@@ -63,22 +63,34 @@ macro_rules! argp {
 //     ($a:expr) => ($a as *const core::ffi::c_void as usize)
 // }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_exit(status: i32) -> ! {
     syscall!(abi::SYS_EXIT, argn!(status));
-    loop {}
+    unreachable!();
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_close(fd: i32) -> i32 {
     syscall!(abi::SYS_CLOSE, argn!(fd)) as i32
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_ex_nanosleep(ns: u64, rem: &mut [u64; 2]) -> i32 {
     syscall!(abi::SYS_EX_NANOSLEEP, argn!(ns), argp!(rem.as_mut_ptr())) as i32
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_ex_debug_trace(msg: &[u8]) -> usize {
     syscall!(
@@ -88,6 +100,9 @@ pub unsafe fn sys_ex_debug_trace(msg: &[u8]) -> usize {
     )
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_openat(at: i32, pathname: &str, mode: FileMode, flags: OpenFlags) -> i32 {
     syscall!(
@@ -100,6 +115,9 @@ pub unsafe fn sys_openat(at: i32, pathname: &str, mode: FileMode, flags: OpenFla
     ) as i32
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_read(fd: i32, data: &mut [u8]) -> isize {
     syscall!(
@@ -110,6 +128,9 @@ pub unsafe fn sys_read(fd: i32, data: &mut [u8]) -> isize {
     ) as isize
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_write(fd: i32, data: &[u8]) -> isize {
     syscall!(
@@ -120,6 +141,9 @@ pub unsafe fn sys_write(fd: i32, data: &[u8]) -> isize {
     ) as isize
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_fstatat(at: i32, pathname: &str, statbuf: &mut Stat, flags: u32) -> i32 {
     syscall!(
@@ -132,11 +156,17 @@ pub unsafe fn sys_fstatat(at: i32, pathname: &str, statbuf: &mut Stat, flags: u3
     ) as i32
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_fork() -> i32 {
     syscall!(abi::SYS_FORK) as i32
 }
 
+/// # Safety
+///
+/// System call
 #[inline(always)]
 pub unsafe fn sys_execve(pathname: &str) -> i32 {
     syscall!(