atrocious

Author: nabijaczleweli

library/std/src/sys/pal/unix/mod.rs

@@ -61,27 +61,30 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
     }
 
     unsafe fn sanitize_standard_fds() {
-        let mut opened_devnull = -1;
-        let mut open_devnull = || {
-            #[cfg(not(all(target_os = "linux", target_env = "gnu")))]
-            use libc::open as open64;
-            #[cfg(all(target_os = "linux", target_env = "gnu"))]
-            use libc::open64;
-
-            if opened_devnull != -1 {
-                if libc::dup(opened_devnull) != -1 {
-                    return;
+        macro_rules! open_devnull {
+            ($opened_devnull:expr) => {
+                'od: {
+                    #[cfg(not(all(target_os = "linux", target_env = "gnu")))]
+                    use libc::open as open64;
+                    #[cfg(all(target_os = "linux", target_env = "gnu"))]
+                    use libc::open64;
+
+                    if $opened_devnull != -1 {
+                        if libc::dup($opened_devnull) != -1 {
+                            break 'od;
+                        }
+                    }
+                    $opened_devnull = open64(c"/dev/null".as_ptr(), libc::O_RDWR, 0);
+                    if $opened_devnull == -1 {
+                        // If the stream is closed but we failed to reopen it, abort the
+                        // process. Otherwise we wouldn't preserve the safety of
+                        // operations on the corresponding Rust object Stdin, Stdout, or
+                        // Stderr.
+                        libc::abort();
+                    }
                 }
-            }
-            opened_devnull = open64(c"/dev/null".as_ptr(), libc::O_RDWR, 0);
-            if opened_devnull == -1 {
-                // If the stream is closed but we failed to reopen it, abort the
-                // process. Otherwise we wouldn't preserve the safety of
-                // operations on the corresponding Rust object Stdin, Stdout, or
-                // Stderr.
-                libc::abort();
-            }
-        };
+            };
+        }
 
         // fast path with a single syscall for systems with poll()
         #[cfg(not(any(
@@ -99,6 +102,7 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
         )))]
         'poll: {
             use crate::sys::os::errno;
+            let mut opened_devnull = -1;
             let pfds: &mut [_] = &mut [
                 libc::pollfd { fd: 0, events: 0, revents: 0 },
                 libc::pollfd { fd: 1, events: 0, revents: 0 },
@@ -125,7 +129,7 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
                 if pfd.revents & libc::POLLNVAL == 0 {
                     continue;
                 }
-                open_devnull();
+                open_devnull!(opened_devnull);
             }
             return;
         }
@@ -143,9 +147,10 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
         )))]
         {
             use crate::sys::os::errno;
+            let mut opened_devnull = -1;
             for fd in 0..3 {
                 if libc::fcntl(fd, libc::F_GETFD) == -1 && errno() == libc::EBADF {
-                    open_devnull();
+                    open_devnull!(opened_devnull);
                 }
             }
         }