Merge branch 'add-mkdirat' into 'master'

Implement mkfifoat(2)

See merge request redox-os/relibc!881

src/header/sys_stat/mod.rs

@@ -176,6 +176,15 @@ pub unsafe extern "C" fn mkdir(path: *const c_char, mode: mode_t) -> c_int {
     Sys::mkdir(path, mode).map(|()| 0).or_minus_one_errno()
 }
 
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkfifoat.html>.
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn mkfifoat(dirfd: c_int, path: *const c_char, mode: mode_t) -> c_int {
+    let path = CStr::from_ptr(path);
+    Sys::mkfifoat(dirfd, path, mode)
+        .map(|()| 0)
+        .or_minus_one_errno()
+}
+
 /// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkfifo.html>.
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn mkfifo(path: *const c_char, mode: mode_t) -> c_int {

src/platform/linux/mod.rs

@@ -527,6 +527,10 @@ impl Pal for Sys {
         Sys::mknodat(AT_FDCWD, path, mode, dev)
     }
 
+    fn mkfifoat(dir_fd: c_int, path: CStr, mode: mode_t) -> Result<()> {
+        Sys::mknodat(dir_fd, path, mode | S_IFIFO, 0)
+    }
+
     fn mkfifo(path: CStr, mode: mode_t) -> Result<()> {
         Sys::mknod(path, mode | S_IFIFO, 0)
     }

src/platform/pal/mod.rs

@@ -175,6 +175,8 @@ pub trait Pal {
 
     fn mkdir(path: CStr, mode: mode_t) -> Result<()>;
 
+    fn mkfifoat(dir_fd: c_int, path: CStr, mode: mode_t) -> Result<()>;
+
     fn mkfifo(path: CStr, mode: mode_t) -> Result<()>;
 
     fn mknodat(fildes: c_int, path: CStr, mode: mode_t, dev: dev_t) -> Result<()>;

src/platform/redox/mod.rs

@@ -708,6 +708,23 @@ impl Pal for Sys {
         Ok(())
     }
 
+    fn mkfifoat(dir_fd: c_int, path_name: CStr, mode: mode_t) -> Result<()> {
+        let mut dir_path_buf = [0; 4096];
+        let res = Sys::fpath(dir_fd, &mut dir_path_buf)?;
+
+        let dir_path = str::from_utf8(&dir_path_buf[..res as usize]).map_err(|_| Errno(EBADR))?;
+
+        let resource_path =
+            path::canonicalize_using_cwd(Some(&dir_path), &path_name.to_string_lossy())
+                // Since parent_dir_path is resolved by fpath, it is more likely that
+                // the problem was with path.
+                .ok_or(Errno(ENOENT))?;
+        Sys::mkfifo(
+            CStr::borrow(&CString::new(resource_path.as_bytes()).unwrap()),
+            mode,
+        )
+    }
+
     fn mkfifo(path: CStr, mode: mode_t) -> Result<()> {
         Sys::mknod(path, syscall::MODE_FIFO as mode_t | (mode & 0o777), 0)
     }
@@ -874,8 +891,8 @@ impl Pal for Sys {
 
         // POSIX states that umask should affect the following:
         //
-        // open, openat (TODO), creat, mkdir, mkdirat (TODO),
-        // mkfifo, mkfifoat (TODO), mknod, mknodat (TODO),
+        // open, openat, creat, mkdir, mkdirat,
+        // mkfifo, mkfifoat, mknod, mknodat,
         // mq_open, and sem_open,
         //
         // all of which (the ones that exist thus far) currently call this function.