Make std tests pass on newer Android

Newer versions of Android forbid the creation of hardlinks as well as
Unix domain sockets in the /data filesystem via SELinux rules, which
causes several tests depending on this behavior to fail. So let's
skip these tests on Android with an #[ignore] directive.

library/std/src/fs/tests.rs

@@ -935,6 +935,7 @@ fn readlink_not_symlink() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating hardlinks
 fn links_work() {
     let tmpdir = tmpdir();
     let input = tmpdir.join("in.txt");
@@ -1431,6 +1432,7 @@ fn metadata_access_times() {
 
 /// Test creating hard links to symlinks.
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating hardlinks
 fn symlink_hard_link() {
     let tmpdir = tmpdir();
     if !got_symlink_permission(&tmpdir) {

library/std/src/os/unix/net/tests.rs

@@ -23,6 +23,7 @@ macro_rules! or_panic {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn basic() {
     let dir = tmpdir();
     let socket_path = dir.path().join("sock");
@@ -93,6 +94,7 @@ fn pair() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn try_clone() {
     let dir = tmpdir();
     let socket_path = dir.path().join("sock");
@@ -119,6 +121,7 @@ fn try_clone() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn iter() {
     let dir = tmpdir();
     let socket_path = dir.path().join("sock");
@@ -168,6 +171,7 @@ fn long_path() {
 
 #[test]
 #[cfg(not(target_os = "nto"))]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn timeouts() {
     let dir = tmpdir();
     let socket_path = dir.path().join("sock");
@@ -195,6 +199,7 @@ fn timeouts() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_read_timeout() {
     let dir = tmpdir();
     let socket_path = dir.path().join("sock");
@@ -214,6 +219,7 @@ fn test_read_timeout() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_read_with_timeout() {
     let dir = tmpdir();
     let socket_path = dir.path().join("sock");
@@ -241,6 +247,7 @@ fn test_read_with_timeout() {
 // Ensure the `set_read_timeout` and `set_write_timeout` calls return errors
 // when passed zero Durations
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_stream_timeout_zero_duration() {
     let dir = tmpdir();
     let socket_path = dir.path().join("sock");
@@ -260,6 +267,7 @@ fn test_unix_stream_timeout_zero_duration() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_datagram() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock1");
@@ -276,6 +284,7 @@ fn test_unix_datagram() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unnamed_unix_datagram() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock1");
@@ -293,6 +302,7 @@ fn test_unnamed_unix_datagram() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_datagram_connect_to_recv_addr() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock1");
@@ -317,6 +327,7 @@ fn test_unix_datagram_connect_to_recv_addr() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_connect_unix_datagram() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock1");
@@ -343,6 +354,7 @@ fn test_connect_unix_datagram() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_datagram_recv() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock1");
@@ -385,6 +397,7 @@ fn datagram_pair() {
 // Ensure the `set_read_timeout` and `set_write_timeout` calls return errors
 // when passed zero Durations
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_datagram_timeout_zero_duration() {
     let dir = tmpdir();
     let path = dir.path().join("sock");
@@ -529,6 +542,7 @@ fn test_abstract_no_pathname_and_not_unnamed() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_stream_peek() {
     let (txdone, rxdone) = crate::sync::mpsc::channel();
 
@@ -561,6 +575,7 @@ fn test_unix_stream_peek() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_datagram_peek() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock");
@@ -585,6 +600,7 @@ fn test_unix_datagram_peek() {
 }
 
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_unix_datagram_peek_from() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock");
@@ -648,6 +664,7 @@ fn test_send_vectored_fds_unix_stream() {
 
 #[cfg(any(target_os = "android", target_os = "linux",))]
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_send_vectored_with_ancillary_to_unix_datagram() {
     fn getpid() -> libc::pid_t {
         unsafe { libc::getpid() }
@@ -715,6 +732,7 @@ fn test_send_vectored_with_ancillary_to_unix_datagram() {
 
 #[cfg(any(target_os = "android", target_os = "linux"))]
 #[test]
+#[cfg_attr(target_os = "android", ignore)] // Android SELinux rules prevent creating Unix sockets
 fn test_send_vectored_with_ancillary_unix_datagram() {
     let dir = tmpdir();
     let path1 = dir.path().join("sock1");