Auto merge of #410 - fiveop:epoll_create1, r=posborne

Add epoll_create1

In order to get @kubo39's PR #384 forward, I cleaned up the commit history a bit and added `EpollEvent` back.

Since this module is used by mio, maybe @carllerche could comment on these changes.

src/sys/epoll.rs

@@ -1,21 +1,10 @@
 use {Errno, Result};
-use libc::c_int;
+use libc::{self, c_int};
 use std::os::unix::io::RawFd;
 
-mod ffi {
-    use libc::{c_int};
-    use super::EpollEvent;
-
-    extern {
-        pub fn epoll_create(size: c_int) -> c_int;
-        pub fn epoll_ctl(epfd: c_int, op: c_int, fd: c_int, event: *const EpollEvent) -> c_int;
-        pub fn epoll_wait(epfd: c_int, events: *mut EpollEvent, max_events: c_int, timeout: c_int) -> c_int;
-    }
-}
-
 bitflags!(
     #[repr(C)]
-    flags EpollEventKind: u32 {
+    flags EpollFlags: u32 {
         const EPOLLIN = 0x001,
         const EPOLLPRI = 0x002,
         const EPOLLOUT = 0x004,
@@ -42,54 +31,57 @@ pub enum EpollOp {
     EpollCtlMod = 3
 }
 
-#[cfg(not(target_arch = "x86_64"))]
-#[derive(Clone, Copy)]
-#[repr(C)]
-pub struct EpollEvent {
-    pub events: EpollEventKind,
-    pub data: u64
+libc_bitflags!{
+    flags EpollCreateFlags: c_int {
+        EPOLL_CLOEXEC,
+    }
 }
 
-#[cfg(target_arch = "x86_64")]
 #[derive(Clone, Copy)]
-#[repr(C, packed)]
+#[repr(C)]
 pub struct EpollEvent {
-    pub events: EpollEventKind,
-    pub data: u64
+    event: libc::epoll_event,
 }
 
-#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
-#[test]
-fn test_epoll_event_size() {
-    use std::mem::size_of;
-    assert_eq!(size_of::<EpollEvent>(), 12);
-}
+impl EpollEvent {
+    pub fn new(events: EpollFlags, data: u64) -> EpollEvent {
+        EpollEvent { event: libc::epoll_event { events: events.bits(), u64: data } }
+    }
+
+    pub fn events(&self) -> EpollFlags {
+        EpollFlags::from_bits(self.event.events).unwrap()
+    }
 
-#[cfg(target_arch = "arm")]
-#[test]
-fn test_epoll_event_size() {
-    use std::mem::size_of;
-    assert_eq!(size_of::<EpollEvent>(), 16);
+    pub fn data(&self) -> u64 {
+        self.event.u64
+    }
 }
 
 #[inline]
 pub fn epoll_create() -> Result<RawFd> {
-    let res = unsafe { ffi::epoll_create(1024) };
+    let res = unsafe { libc::epoll_create(1024) };
+
+    Errno::result(res)
+}
+
+#[inline]
+pub fn epoll_create1(flags: EpollCreateFlags) -> Result<RawFd> {
+    let res = unsafe { libc::epoll_create1(flags.bits()) };
 
     Errno::result(res)
 }
 
 #[inline]
-pub fn epoll_ctl(epfd: RawFd, op: EpollOp, fd: RawFd, event: &EpollEvent) -> Result<()> {
-    let res = unsafe { ffi::epoll_ctl(epfd, op as c_int, fd, event as *const EpollEvent) };
+pub fn epoll_ctl(epfd: RawFd, op: EpollOp, fd: RawFd, event: &mut EpollEvent) -> Result<()> {
+    let res = unsafe { libc::epoll_ctl(epfd, op as c_int, fd, &mut event.event) };
 
     Errno::result(res).map(drop)
 }
 
 #[inline]
 pub fn epoll_wait(epfd: RawFd, events: &mut [EpollEvent], timeout_ms: isize) -> Result<usize> {
     let res = unsafe {
-        ffi::epoll_wait(epfd, events.as_mut_ptr(), events.len() as c_int, timeout_ms as c_int)
+        libc::epoll_wait(epfd, events.as_mut_ptr() as *mut libc::epoll_event, events.len() as c_int, timeout_ms as c_int)
     };
 
     Errno::result(res).map(|r| r as usize)