Add unistd::symlink function

src/cmd/mknod/mod.rs

@@ -1,7 +1,8 @@
 use super::Cmd;
 use crate::{
     args,
-    mode::{get_umask, Parser}, stat,
+    mode::{get_umask, Parser},
+    stat,
 };
 use clap::{value_parser, Arg, ArgMatches, Command};
 use std::{convert::Infallible, error::Error, io, str::FromStr};

src/cmd/sync/mod.rs

@@ -2,7 +2,7 @@ use crate::unistd;
 
 use super::Cmd;
 use clap::{Arg, ArgAction, Command};
-use std::{error::Error, io, fs::OpenOptions};
+use std::{error::Error, fs::OpenOptions, io};
 
 #[derive(Debug, Default)]
 pub struct Sync;

src/unistd/mod.rs

@@ -1,6 +1,6 @@
 use libc::utsname;
 use sc::syscall;
-use std::{ffi::CString, io, u8, fs::File, os::fd::AsRawFd};
+use std::{ffi::CString, fs::File, io, os::fd::AsRawFd, u8};
 
 #[inline(always)]
 fn new_utsname() -> utsname {
@@ -70,9 +70,20 @@ pub fn unlink(name: &str) -> io::Result<()> {
 #[inline(always)]
 pub fn readlink(name: &str) -> io::Result<String> {
     let mut buf = Vec::<i8>::with_capacity(1024);
-    let ret = unsafe { syscall!(READLINK, CString::new(name)?.as_ptr(), buf.as_mut_ptr(), 1024) };
+    let ret = unsafe {
+        syscall!(
+            READLINK,
+            CString::new(name)?.as_ptr(),
+            buf.as_mut_ptr(),
+            1024
+        )
+    };
     if ret == 0 {
-        let path = buf.iter().map(|x| *x as u8).take_while(|x| *x != 0).collect();
+        let path = buf
+            .iter()
+            .map(|x| *x as u8)
+            .take_while(|x| *x != 0)
+            .collect();
         String::from_utf8(path).map_err(|e| io::Error::new(io::ErrorKind::Other, e))
     } else {
         Err(io::Error::last_os_error())
@@ -113,3 +124,19 @@ pub fn fsync(fd: &File) -> io::Result<()> {
 pub fn sync() {
     unsafe { syscall!(SYNC) };
 }
+
+#[inline(always)]
+pub fn symlink(source: &str, dest: &str) -> io::Result<()> {
+    let ret = unsafe {
+        syscall!(
+            SYMLINK,
+            CString::new(source)?.as_ptr(),
+            CString::new(dest)?.as_ptr()
+        )
+    };
+    if ret == 0 {
+        Ok(())
+    } else {
+        Err(io::Error::last_os_error())
+    }
+}