Use SOCK_CLOEXEC and accept4() on more platforms.

Author: de-vri-es

Diff for: library/std/src/sys/unix/net.rs

@@ -55,9 +55,18 @@ impl Socket {
     pub fn new_raw(fam: c_int, ty: c_int) -> io::Result<Socket> {
         unsafe {
             cfg_if::cfg_if! {
-                if #[cfg(target_os = "linux")] {
-                    // On Linux we pass the SOCK_CLOEXEC flag to atomically create
-                    // the socket and set it as CLOEXEC, added in 2.6.27.
+                if #[cfg(any(
+                    target_os = "android",
+                    target_os = "dragonfly",
+                    target_os = "freebsd",
+                    target_os = "illumos",
+                    target_os = "linux",
+                    target_os = "netbsd",
+                    target_os = "opensbd",
+                ))] {
+                    // On platforms that support it we pass the SOCK_CLOEXEC
+                    // flag to atomically create the socket and set it as
+                    // CLOEXEC. On Linux this was added in 2.6.27.
                     let fd = cvt(libc::socket(fam, ty | libc::SOCK_CLOEXEC, 0))?;
                     Ok(Socket(FileDesc::new(fd)))
                 } else {
@@ -83,7 +92,15 @@ impl Socket {
             let mut fds = [0, 0];
 
             cfg_if::cfg_if! {
-                if #[cfg(target_os = "linux")] {
+                if #[cfg(any(
+                    target_os = "android",
+                    target_os = "dragonfly",
+                    target_os = "freebsd",
+                    target_os = "illumos",
+                    target_os = "linux",
+                    target_os = "netbsd",
+                    target_os = "opensbd",
+                ))] {
                     // Like above, set cloexec atomically
                     cvt(libc::socketpair(fam, ty | libc::SOCK_CLOEXEC, 0, fds.as_mut_ptr()))?;
                     Ok((Socket(FileDesc::new(fds[0])), Socket(FileDesc::new(fds[1]))))
@@ -174,9 +191,18 @@ impl Socket {
     pub fn accept(&self, storage: *mut sockaddr, len: *mut socklen_t) -> io::Result<Socket> {
         // Unfortunately the only known way right now to accept a socket and
         // atomically set the CLOEXEC flag is to use the `accept4` syscall on
-        // Linux. This was added in 2.6.28, glibc 2.10 and musl 0.9.5.
+        // platforms that support it. On Linux, this was added in 2.6.28,
+        // glibc 2.10 and musl 0.9.5.
         cfg_if::cfg_if! {
-            if #[cfg(target_os = "linux")] {
+            if #[cfg(any(
+                target_os = "android",
+                target_os = "dragonfly",
+                target_os = "freebsd",
+                target_os = "illumos",
+                target_os = "linux",
+                target_os = "netbsd",
+                target_os = "opensbd",
+            ))] {
                 let fd = cvt_r(|| unsafe {
                     libc::accept4(self.0.raw(), storage, len, libc::SOCK_CLOEXEC)
                 })?;