Auto merge of #43056 - ids1024:nofollow2, r=burntsushi

Redox: Use O_NOFOLLOW for lstat()

src/libstd/sys/redox/fs.rs

@@ -447,7 +447,10 @@ pub fn stat(p: &Path) -> io::Result<FileAttr> {
 }
 
 pub fn lstat(p: &Path) -> io::Result<FileAttr> {
-    stat(p)
+    let fd = cvt(syscall::open(p.to_str().unwrap(),
+                               syscall::O_CLOEXEC | syscall::O_STAT | syscall::O_NOFOLLOW))?;
+    let file = File(FileDesc::new(fd));
+    file.file_attr()
 }
 
 pub fn canonicalize(p: &Path) -> io::Result<PathBuf> {

src/libstd/sys/redox/syscall/flag.rs

@@ -55,6 +55,7 @@
 pub const O_DIRECTORY: usize =  0x1000_0000;
 pub const O_STAT: usize =       0x2000_0000;
 pub const O_SYMLINK: usize =    0x4000_0000;
+pub const O_NOFOLLOW: usize =   0x8000_0000;
 pub const O_ACCMODE: usize =    O_RDONLY | O_WRONLY | O_RDWR;
 
 pub const SEEK_SET: usize = 0;