diff options
| -rw-r--r-- | library/std/src/sys/unix/fs.rs | 41 | ||||
| -rw-r--r-- | library/std/src/sys/unix/os.rs | 2 |
2 files changed, 30 insertions, 13 deletions
diff --git a/library/std/src/sys/unix/fs.rs b/library/std/src/sys/unix/fs.rs index 14e8f06b303..d1bd1f6d0eb 100644 --- a/library/std/src/sys/unix/fs.rs +++ b/library/std/src/sys/unix/fs.rs @@ -34,6 +34,17 @@ use libc::c_char; use libc::dirfd; #[cfg(any(target_os = "linux", target_os = "emscripten"))] use libc::fstatat64; +#[cfg(any( + target_os = "solaris", + target_os = "fuchsia", + target_os = "redox", + target_os = "illumos" +))] +use libc::readdir as readdir64; +#[cfg(target_os = "linux")] +use libc::readdir64; +#[cfg(any(target_os = "emscripten", target_os = "l4re"))] +use libc::readdir64_r; #[cfg(not(any( target_os = "linux", target_os = "emscripten", @@ -60,9 +71,7 @@ use libc::{ lstat as lstat64, off_t as off64_t, open as open64, stat as stat64, }; #[cfg(any(target_os = "linux", target_os = "emscripten", target_os = "l4re"))] -use libc::{ - dirent64, fstat64, ftruncate64, lseek64, lstat64, off64_t, open64, readdir64_r, stat64, -}; +use libc::{dirent64, fstat64, ftruncate64, lseek64, lstat64, off64_t, open64, stat64}; pub use crate::sys_common::fs::try_exists; @@ -202,6 +211,7 @@ struct InnerReadDir { pub struct ReadDir { inner: Arc<InnerReadDir>, #[cfg(not(any( + target_os = "linux", target_os = "solaris", target_os = "illumos", target_os = "fuchsia", @@ -218,11 +228,11 @@ unsafe impl Sync for Dir {} pub struct DirEntry { entry: dirent64, dir: Arc<InnerReadDir>, - // We need to store an owned copy of the entry name - // on Solaris and Fuchsia because a) it uses a zero-length - // array to store the name, b) its lifetime between readdir - // calls is not guaranteed. + // We need to store an owned copy of the entry name on platforms that use + // readdir() (not readdir_r()), because a) struct dirent may use a flexible + // array to store the name, b) it lives only until the next readdir() call. #[cfg(any( + target_os = "linux", target_os = "solaris", target_os = "illumos", target_os = "fuchsia", @@ -449,6 +459,7 @@ impl Iterator for ReadDir { type Item = io::Result<DirEntry>; #[cfg(any( + target_os = "linux", target_os = "solaris", target_os = "fuchsia", target_os = "redox", @@ -457,12 +468,13 @@ impl Iterator for ReadDir { fn next(&mut self) -> Option<io::Result<DirEntry>> { unsafe { loop { - // Although readdir_r(3) would be a correct function to use here because - // of the thread safety, on Illumos and Fuchsia the readdir(3C) function - // is safe to use in threaded applications and it is generally preferred - // over the readdir_r(3C) function. + // As of POSIX.1-2017, readdir() is not required to be thread safe; only + // readdir_r() is. However, readdir_r() cannot correctly handle platforms + // with unlimited or variable NAME_MAX. Many modern platforms guarantee + // thread safety for readdir() as long an individual DIR* is not accessed + // concurrently, which is sufficient for Rust. super::os::set_errno(0); - let entry_ptr = libc::readdir(self.inner.dirp.0); + let entry_ptr = readdir64(self.inner.dirp.0); if entry_ptr.is_null() { // null can mean either the end is reached or an error occurred. // So we had to clear errno beforehand to check for an error now. @@ -486,6 +498,7 @@ impl Iterator for ReadDir { } #[cfg(not(any( + target_os = "linux", target_os = "solaris", target_os = "fuchsia", target_os = "redox", @@ -652,6 +665,7 @@ impl DirEntry { } #[cfg(not(any( + target_os = "linux", target_os = "solaris", target_os = "illumos", target_os = "fuchsia", @@ -661,6 +675,7 @@ impl DirEntry { unsafe { CStr::from_ptr(self.entry.d_name.as_ptr()) } } #[cfg(any( + target_os = "linux", target_os = "solaris", target_os = "illumos", target_os = "fuchsia", @@ -1071,6 +1086,7 @@ pub fn readdir(p: &Path) -> io::Result<ReadDir> { Ok(ReadDir { inner: Arc::new(inner), #[cfg(not(any( + target_os = "linux", target_os = "solaris", target_os = "illumos", target_os = "fuchsia", @@ -1606,6 +1622,7 @@ mod remove_dir_impl { ReadDir { inner: Arc::new(InnerReadDir { dirp, root: dummy_root }), #[cfg(not(any( + target_os = "linux", target_os = "solaris", target_os = "illumos", target_os = "fuchsia", diff --git a/library/std/src/sys/unix/os.rs b/library/std/src/sys/unix/os.rs index 8a028d99306..7466c77356c 100644 --- a/library/std/src/sys/unix/os.rs +++ b/library/std/src/sys/unix/os.rs @@ -75,7 +75,7 @@ pub fn errno() -> i32 { } /// Sets the platform-specific value of errno -#[cfg(all(not(target_os = "linux"), not(target_os = "dragonfly"), not(target_os = "vxworks")))] // needed for readdir and syscall! +#[cfg(all(not(target_os = "dragonfly"), not(target_os = "vxworks")))] // needed for readdir and syscall! #[allow(dead_code)] // but not all target cfgs actually end up using it pub fn set_errno(e: i32) { unsafe { *errno_location() = e as c_int } |