Auto merge of #124879 - workingjubilee:rollup-1k77hyz, r=workingjubilee

Rollup of 4 pull requests

Successful merges:

 - #124470 (std::net: Socket::new_raw now set to SO_NOSIGPIPE on freebsd.)
 - #124782 (add note about `AlreadyExists` to `create_new`)
 - #124788 (Convert instances of `target_os = "macos"` to `target_vendor = "apple"`)
 - #124838 (next_power_of_two: add a doctest to show what happens on 0)

r? `@ghost`
`@rustbot` modify labels: rollup

7 files changed, 49 insertions, 22 deletions

diff --git a/library/std/src/fs.rs b/library/std/src/fs.rs
index a59faf551e8..77e94365b08 100644
--- a/library/std/src/fs.rs
+++ b/library/std/src/fs.rs
@@ -408,6 +408,9 @@ impl File {
     ///
     /// This function will create a file if it does not exist, or return an error if it does. This
     /// way, if the call succeeds, the file returned is guaranteed to be new.
+    /// If a file exists at the target location, creating a new file will fail with [`AlreadyExists`]
+    /// or another error based on the situation. See [`OpenOptions::open`] for a
+    /// non-exhaustive list of likely errors.
     ///
     /// This option is useful because it is atomic. Otherwise between checking whether a file
     /// exists and creating a new one, the file may have been created by another process (a TOCTOU
@@ -416,6 +419,8 @@ impl File {
     /// This can also be written using
     /// `File::options().read(true).write(true).create_new(true).open(...)`.
     ///
+    /// [`AlreadyExists`]: crate::io::ErrorKind::AlreadyExists
+    ///
     /// # Examples
     ///
     /// ```no_run
@@ -1071,6 +1076,9 @@ impl OpenOptions {
     ///
     /// No file is allowed to exist at the target location, also no (dangling) symlink. In this
     /// way, if the call succeeds, the file returned is guaranteed to be new.
+    /// If a file exists at the target location, creating a new file will fail with [`AlreadyExists`]
+    /// or another error based on the situation. See [`OpenOptions::open`] for a
+    /// non-exhaustive list of likely errors.
     ///
     /// This option is useful because it is atomic. Otherwise between checking
     /// whether a file exists and creating a new one, the file may have been
@@ -1084,6 +1092,7 @@ impl OpenOptions {
     ///
     /// [`.create()`]: OpenOptions::create
     /// [`.truncate()`]: OpenOptions::truncate
+    /// [`AlreadyExists`]: io::ErrorKind::AlreadyExists
     ///
     /// # Examples
     ///
diff --git a/library/std/src/os/unix/net/listener.rs b/library/std/src/os/unix/net/listener.rs
index 7e53acbc387..a55199c82fc 100644
--- a/library/std/src/os/unix/net/listener.rs
+++ b/library/std/src/os/unix/net/listener.rs
@@ -81,21 +81,25 @@ impl UnixListener {
             ))]
             const backlog: core::ffi::c_int = 128;
             #[cfg(any(
+                // Silently capped to `/proc/sys/net/core/somaxconn`.
                 target_os = "linux",
+                // Silently capped to `kern.ipc.soacceptqueue`.
                 target_os = "freebsd",
+                // Silently capped to `kern.somaxconn sysctl`.
                 target_os = "openbsd",
-                target_os = "macos"
+                // Silently capped to the default 128.
+                target_vendor = "apple",
             ))]
             const backlog: core::ffi::c_int = -1;
             #[cfg(not(any(
                 target_os = "windows",
                 target_os = "redox",
+                target_os = "espidf",
+                target_os = "horizon",
                 target_os = "linux",
                 target_os = "freebsd",
                 target_os = "openbsd",
-                target_os = "macos",
-                target_os = "espidf",
-                target_os = "horizon"
+                target_vendor = "apple",
             )))]
             const backlog: libc::c_int = libc::SOMAXCONN;
 
diff --git a/library/std/src/sys/pal/unix/alloc.rs b/library/std/src/sys/pal/unix/alloc.rs
index af0089978ec..9938c0bac25 100644
--- a/library/std/src/sys/pal/unix/alloc.rs
+++ b/library/std/src/sys/pal/unix/alloc.rs
@@ -13,7 +13,13 @@ unsafe impl GlobalAlloc for System {
         if layout.align() <= MIN_ALIGN && layout.align() <= layout.size() {
             libc::malloc(layout.size()) as *mut u8
         } else {
-            #[cfg(target_os = "macos")]
+            // `posix_memalign` returns a non-aligned value if supplied a very
+            // large alignment on older versions of Apple's platforms (unknown
+            // exactly which version range, but the issue is definitely
+            // present in macOS 10.14 and iOS 13.3).
+            //
+            // <https://github.com/rust-lang/rust/issues/30170>
+            #[cfg(target_vendor = "apple")]
             {
                 if layout.align() > (1 << 31) {
                     return ptr::null_mut();
diff --git a/library/std/src/sys/pal/unix/fd.rs b/library/std/src/sys/pal/unix/fd.rs
index 203c7180001..1701717db59 100644
--- a/library/std/src/sys/pal/unix/fd.rs
+++ b/library/std/src/sys/pal/unix/fd.rs
@@ -33,14 +33,15 @@ pub struct FileDesc(OwnedFd);
 // with the man page quoting that if the count of bytes to read is
 // greater than `SSIZE_MAX` the result is "unspecified".
 //
-// On macOS, however, apparently the 64-bit libc is either buggy or
+// On Apple targets however, apparently the 64-bit libc is either buggy or
 // intentionally showing odd behavior by rejecting any read with a size
 // larger than or equal to INT_MAX. To handle both of these the read
 // size is capped on both platforms.
-#[cfg(target_os = "macos")]
-const READ_LIMIT: usize = libc::c_int::MAX as usize - 1;
-#[cfg(not(target_os = "macos"))]
-const READ_LIMIT: usize = libc::ssize_t::MAX as usize;
+const READ_LIMIT: usize = if cfg!(target_vendor = "apple") {
+    libc::c_int::MAX as usize - 1
+} else {
+    libc::ssize_t::MAX as usize
+};
 
 #[cfg(any(
     target_os = "dragonfly",
diff --git a/library/std/src/sys/pal/unix/fs.rs b/library/std/src/sys/pal/unix/fs.rs
index 32cdd13fbeb..fbbd40bfb79 100644
--- a/library/std/src/sys/pal/unix/fs.rs
+++ b/library/std/src/sys/pal/unix/fs.rs
@@ -1493,11 +1493,11 @@ impl fmt::Debug for File {
             readlink(&p).ok()
         }
 
-        #[cfg(target_os = "macos")]
+        #[cfg(target_vendor = "apple")]
         fn get_path(fd: c_int) -> Option<PathBuf> {
             // FIXME: The use of PATH_MAX is generally not encouraged, but it
-            // is inevitable in this case because macOS defines `fcntl` with
-            // `F_GETPATH` in terms of `MAXPATHLEN`, and there are no
+            // is inevitable in this case because Apple targets define `fcntl`
+            // with `F_GETPATH` in terms of `MAXPATHLEN`, and there are no
             // alternatives. If a better method is invented, it should be used
             // instead.
             let mut buf = vec![0; libc::PATH_MAX as usize];
@@ -1538,12 +1538,12 @@ impl fmt::Debug for File {
 
         #[cfg(not(any(
             target_os = "linux",
-            target_os = "macos",
             target_os = "vxworks",
             all(target_os = "freebsd", target_arch = "x86_64"),
             target_os = "netbsd",
             target_os = "illumos",
-            target_os = "solaris"
+            target_os = "solaris",
+            target_vendor = "apple",
         )))]
         fn get_path(_fd: c_int) -> Option<PathBuf> {
             // FIXME(#24570): implement this for other Unix platforms
@@ -1552,12 +1552,12 @@ impl fmt::Debug for File {
 
         #[cfg(any(
             target_os = "linux",
-            target_os = "macos",
             target_os = "freebsd",
             target_os = "hurd",
             target_os = "netbsd",
             target_os = "openbsd",
-            target_os = "vxworks"
+            target_os = "vxworks",
+            target_vendor = "apple",
         ))]
         fn get_mode(fd: c_int) -> Option<(bool, bool)> {
             let mode = unsafe { libc::fcntl(fd, libc::F_GETFL) };
@@ -1574,12 +1574,12 @@ impl fmt::Debug for File {
 
         #[cfg(not(any(
             target_os = "linux",
-            target_os = "macos",
             target_os = "freebsd",
             target_os = "hurd",
             target_os = "netbsd",
             target_os = "openbsd",
-            target_os = "vxworks"
+            target_os = "vxworks",
+            target_vendor = "apple",
         )))]
         fn get_mode(_fd: c_int) -> Option<(bool, bool)> {
             // FIXME(#24570): implement this for other Unix platforms
diff --git a/library/std/src/sys/pal/unix/mod.rs b/library/std/src/sys/pal/unix/mod.rs
index 1ac5729c02f..21f233e2262 100644
--- a/library/std/src/sys/pal/unix/mod.rs
+++ b/library/std/src/sys/pal/unix/mod.rs
@@ -63,11 +63,11 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
     args::init(argc, argv);
 
     // Normally, `thread::spawn` will call `Thread::set_name` but since this thread
-    // already exists, we have to call it ourselves. We only do this on macos
+    // already exists, we have to call it ourselves. We only do this on Apple targets
     // because some unix-like operating systems such as Linux share process-id and
     // thread-id for the main thread and so renaming the main thread will rename the
     // process and we only want to enable this on platforms we've tested.
-    if cfg!(target_os = "macos") {
+    if cfg!(target_vendor = "apple") {
         thread::Thread::set_name(&c"main");
     }
 
diff --git a/library/std/src/sys/pal/unix/net.rs b/library/std/src/sys/pal/unix/net.rs
index 7237989c905..b8dc1538a63 100644
--- a/library/std/src/sys/pal/unix/net.rs
+++ b/library/std/src/sys/pal/unix/net.rs
@@ -86,7 +86,14 @@ impl Socket {
                     // 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::from_raw_fd(fd)))
+                    let socket = Socket(FileDesc::from_raw_fd(fd));
+
+                    // DragonFlyBSD, FreeBSD and NetBSD use `SO_NOSIGPIPE` as a `setsockopt`
+                    // flag to disable `SIGPIPE` emission on socket.
+                    #[cfg(any(target_os = "freebsd", target_os = "netbsd", target_os = "dragonfly"))]
+                    setsockopt(&socket, libc::SOL_SOCKET, libc::SO_NOSIGPIPE, 1)?;
+
+                    Ok(socket)
                 } else {
                     let fd = cvt(libc::socket(fam, ty, 0))?;
                     let fd = FileDesc::from_raw_fd(fd);