Add ESP-IDF framework support

Mostly fixing compiler errors but also working around nonblocking issues
with accept, eventfd, etc.

Closes #1691

Author: jasta

src/sys/unix/net.rs

@@ -44,18 +44,20 @@ pub(crate) fn new_socket(domain: libc::c_int, socket_type: libc::c_int) -> io::R
         return Err(err);
     }
 
-    // Darwin doesn't have SOCK_NONBLOCK or SOCK_CLOEXEC.
+    // Darwin (and others) doesn't have SOCK_NONBLOCK or SOCK_CLOEXEC.
     #[cfg(any(
         target_os = "ios",
         target_os = "macos",
         target_os = "tvos",
         target_os = "watchos",
+        target_os = "espidf",
     ))]
     {
         if let Err(err) = syscall!(fcntl(socket, libc::F_SETFL, libc::O_NONBLOCK)) {
             let _ = syscall!(close(socket));
             return Err(err);
         }
+        #[cfg(not(target_os = "espidf"))]
         if let Err(err) = syscall!(fcntl(socket, libc::F_SETFD, libc::FD_CLOEXEC)) {
             let _ = syscall!(close(socket));
             return Err(err);
@@ -105,6 +107,7 @@ pub(crate) fn socket_addr(addr: &SocketAddr) -> (SocketAddrCRepr, libc::socklen_
                     target_os = "openbsd",
                     target_os = "tvos",
                     target_os = "watchos",
+                    target_os = "espidf",
                 ))]
                 sin_len: 0,
             };
@@ -131,6 +134,7 @@ pub(crate) fn socket_addr(addr: &SocketAddr) -> (SocketAddrCRepr, libc::socklen_
                     target_os = "openbsd",
                     target_os = "tvos",
                     target_os = "watchos",
+                    target_os = "espidf",
                 ))]
                 sin6_len: 0,
                 #[cfg(target_os = "illumos")]

src/sys/unix/pipe.rs

@@ -168,6 +168,7 @@ pub fn new() -> io::Result<(Sender, Receiver)> {
         target_os = "macos",
         target_os = "tvos",
         target_os = "watchos",
+        target_os = "espidf",
     ))]
     unsafe {
         // For platforms that don't have `pipe2(2)` we need to manually set the
@@ -202,6 +203,7 @@ pub fn new() -> io::Result<(Sender, Receiver)> {
         target_os = "redox",
         target_os = "tvos",
         target_os = "watchos",
+        target_os = "espidf",
     )))]
     compile_error!("unsupported target for `mio::unix::pipe`");
 

src/sys/unix/tcp.rs

@@ -87,6 +87,7 @@ pub(crate) fn accept(listener: &net::TcpListener) -> io::Result<(net::TcpStream,
         target_os = "redox",
         target_os = "tvos",
         target_os = "watchos",
+        target_os = "espidf",
         all(target_arch = "x86", target_os = "android"),
     ))]
     let stream = {
@@ -97,10 +98,11 @@ pub(crate) fn accept(listener: &net::TcpListener) -> io::Result<(net::TcpStream,
         ))
         .map(|socket| unsafe { net::TcpStream::from_raw_fd(socket) })
         .and_then(|s| {
+            #[cfg(not(target_os = "espidf"))]
             syscall!(fcntl(s.as_raw_fd(), libc::F_SETFD, libc::FD_CLOEXEC))?;
 
             // See https://github.com/tokio-rs/mio/issues/1450
-            #[cfg(all(target_arch = "x86", target_os = "android"))]
+            #[cfg(any(all(target_arch = "x86", target_os = "android"), target_os = "espidf",))]
             syscall!(fcntl(s.as_raw_fd(), libc::F_SETFL, libc::O_NONBLOCK))?;
 
             Ok(s)

src/sys/unix/uds/listener.rs

@@ -41,6 +41,7 @@ pub(crate) fn accept(listener: &net::UnixListener) -> io::Result<(UnixStream, So
         target_os = "redox",
         target_os = "tvos",
         target_os = "watchos",
+        target_os = "espidf",
         // Android x86's seccomp profile forbids calls to `accept4(2)`
         // See https://github.com/tokio-rs/mio/issues/1445 for details
         all(target_arch = "x86", target_os = "android"),
@@ -63,6 +64,7 @@ pub(crate) fn accept(listener: &net::UnixListener) -> io::Result<(UnixStream, So
         target_os = "redox",
         target_os = "tvos",
         target_os = "watchos",
+        target_os = "espidf",
         all(target_arch = "x86", target_os = "android")
     ))]
     let socket = syscall!(accept(
@@ -74,10 +76,11 @@ pub(crate) fn accept(listener: &net::UnixListener) -> io::Result<(UnixStream, So
         // Ensure the socket is closed if either of the `fcntl` calls
         // error below.
         let s = unsafe { net::UnixStream::from_raw_fd(socket) };
+        #[cfg(not(target_os = "espidf"))]
         syscall!(fcntl(socket, libc::F_SETFD, libc::FD_CLOEXEC))?;
 
         // See https://github.com/tokio-rs/mio/issues/1450
-        #[cfg(all(target_arch = "x86", target_os = "android"))]
+        #[cfg(any(all(target_arch = "x86", target_os = "android"), target_os = "espidf",))]
         syscall!(fcntl(socket, libc::F_SETFL, libc::O_NONBLOCK))?;
 
         Ok(s)

src/sys/unix/uds/mod.rs

@@ -82,14 +82,15 @@ cfg_os_poll! {
             target_os = "macos",
             target_os = "tvos",
             target_os = "watchos",
+            target_os = "espidf",
         )))]
         let flags = flags | libc::SOCK_NONBLOCK | libc::SOCK_CLOEXEC;
 
         let mut fds = [-1; 2];
         syscall!(socketpair(libc::AF_UNIX, flags, 0, fds.as_mut_ptr()))?;
         let pair = unsafe { (T::from_raw_fd(fds[0]), T::from_raw_fd(fds[1])) };
 
-        // Darwin doesn't have SOCK_NONBLOCK or SOCK_CLOEXEC.
+        // Darwin (and others) doesn't have SOCK_NONBLOCK or SOCK_CLOEXEC.
         //
         // In order to set those flags, additional `fcntl` sys calls must be
         // performed. If a `fnctl` fails after the sockets have been created,
@@ -100,11 +101,14 @@ cfg_os_poll! {
             target_os = "macos",
             target_os = "tvos",
             target_os = "watchos",
+            target_os = "espidf",
         ))]
         {
             syscall!(fcntl(fds[0], libc::F_SETFL, libc::O_NONBLOCK))?;
+            #[cfg(not(target_os = "espidf"))]
             syscall!(fcntl(fds[0], libc::F_SETFD, libc::FD_CLOEXEC))?;
             syscall!(fcntl(fds[1], libc::F_SETFL, libc::O_NONBLOCK))?;
+            #[cfg(not(target_os = "espidf"))]
             syscall!(fcntl(fds[1], libc::F_SETFD, libc::FD_CLOEXEC))?;
         }
         Ok(pair)

src/sys/unix/waker.rs

@@ -66,7 +66,7 @@ pub use self::fdbased::Waker;
 
 #[cfg(all(
     not(mio_unsupported_force_waker_pipe),
-    any(target_os = "linux", target_os = "android")
+    any(target_os = "linux", target_os = "android", target_os = "espidf")
 ))]
 mod eventfd {
     use std::fs::File;
@@ -86,7 +86,13 @@ mod eventfd {
 
     impl WakerInternal {
         pub fn new() -> io::Result<WakerInternal> {
-            let fd = syscall!(eventfd(0, libc::EFD_CLOEXEC | libc::EFD_NONBLOCK))?;
+            #[cfg(not(target_os = "espidf"))]
+            let flags = libc::EFD_CLOEXEC | libc::EFD_NONBLOCK;
+            // ESP-IDF is EFD_NONBLOCK by default and errors if you try to pass this flag.
+            #[cfg(target_os = "espidf")]
+            let flags = 0;
+            let fd = syscall!(eventfd(0, flags))?;
+
             let file = unsafe { File::from_raw_fd(fd) };
             Ok(WakerInternal { fd: file })
         }
@@ -133,7 +139,7 @@ mod eventfd {
 #[cfg(all(
     mio_unsupported_force_poll_poll,
     not(mio_unsupported_force_waker_pipe),
-    any(target_os = "linux", target_os = "android")
+    any(target_os = "linux", target_os = "android", target_os = "espidf")
 ))]
 pub(crate) use self::eventfd::WakerInternal;