diff options
| -rw-r--r-- | src/sys/select.rs | 111 |
1 files changed, 37 insertions, 74 deletions
diff --git a/src/sys/select.rs b/src/sys/select.rs index 82b2aad3..07190fa1 100644 --- a/src/sys/select.rs +++ b/src/sys/select.rs @@ -1,57 +1,37 @@ -use std::ptr::null_mut; +use std::mem; use std::os::unix::io::RawFd; -use libc::{c_int, timeval}; +use std::ptr::null_mut; +use libc::{self, c_int}; use {Errno, Result}; use sys::time::TimeVal; -pub const FD_SETSIZE: RawFd = 1024; +pub use libc::FD_SETSIZE; -#[cfg(any(target_os = "macos", target_os = "ios"))] +// FIXME: Change to repr(transparent) once it's stable #[repr(C)] -#[derive(Clone)] -pub struct FdSet { - bits: [i32; FD_SETSIZE as usize / 32] -} - -#[cfg(any(target_os = "macos", target_os = "ios"))] -const BITS: usize = 32; - -#[cfg(not(any(target_os = "macos", target_os = "ios")))] -#[repr(C)] -#[derive(Clone)] -pub struct FdSet { - bits: [u64; FD_SETSIZE as usize / 64] -} - -#[cfg(not(any(target_os = "macos", target_os = "ios")))] -const BITS: usize = 64; +pub struct FdSet(libc::fd_set); impl FdSet { pub fn new() -> FdSet { - FdSet { - bits: [0; FD_SETSIZE as usize / BITS] - } + let mut fdset = unsafe { mem::uninitialized() }; + unsafe { libc::FD_ZERO(&mut fdset) }; + FdSet(fdset) } pub fn insert(&mut self, fd: RawFd) { - let fd = fd as usize; - self.bits[fd / BITS] |= 1 << (fd % BITS); + unsafe { libc::FD_SET(fd, &mut self.0) }; } pub fn remove(&mut self, fd: RawFd) { - let fd = fd as usize; - self.bits[fd / BITS] &= !(1 << (fd % BITS)); + unsafe { libc::FD_CLR(fd, &mut self.0) }; } - pub fn contains(&self, fd: RawFd) -> bool { - let fd = fd as usize; - self.bits[fd / BITS] & (1 << (fd % BITS)) > 0 + pub fn contains(&mut self, fd: RawFd) -> bool { + unsafe { libc::FD_ISSET(fd, &mut self.0) } } pub fn clear(&mut self) { - for bits in &mut self.bits { - *bits = 0 - } + unsafe { libc::FD_ZERO(&mut self.0) }; } /// Finds the highest file descriptor in the set. @@ -74,16 +54,11 @@ impl FdSet { /// ``` /// /// [`select`]: fn.select.html - pub fn highest(&self) -> Option<RawFd> { - for (i, &block) in self.bits.iter().enumerate().rev() { - if block != 0 { - // Highest bit is located at `BITS - 1 - n.leading_zeros()`. Examples: - // 0b00000001 - // 7 leading zeros, result should be 0 (bit at index 0 is 1) - // 0b001xxxxx - // 2 leading zeros, result should be 5 (bit at index 5 is 1) - x may be 0 or 1 - - return Some((i * BITS + BITS - 1 - block.leading_zeros() as usize) as RawFd); + pub fn highest(&mut self) -> Option<RawFd> { + for i in (0..libc::FD_SETSIZE).rev() { + let i = i as RawFd; + if unsafe { libc::FD_ISSET(i, self as *mut _ as *mut libc::fd_set) } { + return Some(i) } } @@ -91,19 +66,6 @@ impl FdSet { } } -mod ffi { - use libc::{c_int, timeval}; - use super::FdSet; - - extern { - pub fn select(nfds: c_int, - readfds: *mut FdSet, - writefds: *mut FdSet, - errorfds: *mut FdSet, - timeout: *mut timeval) -> c_int; - } -} - /// Monitors file descriptors for readiness (see [select(2)]). /// /// Returns the total number of ready file descriptors in all sets. The sets are changed so that all @@ -136,28 +98,28 @@ where E: Into<Option<&'a mut FdSet>>, T: Into<Option<&'a mut TimeVal>>, { - let readfds = readfds.into(); - let writefds = writefds.into(); - let errorfds = errorfds.into(); + let mut readfds = readfds.into(); + let mut writefds = writefds.into(); + let mut errorfds = errorfds.into(); let timeout = timeout.into(); let nfds = nfds.into().unwrap_or_else(|| { - readfds.iter() - .chain(writefds.iter()) - .chain(errorfds.iter()) + readfds.iter_mut() + .chain(writefds.iter_mut()) + .chain(errorfds.iter_mut()) .map(|set| set.highest().unwrap_or(-1)) .max() .unwrap_or(-1) + 1 }); - let readfds = readfds.map(|set| set as *mut FdSet).unwrap_or(null_mut()); - let writefds = writefds.map(|set| set as *mut FdSet).unwrap_or(null_mut()); - let errorfds = errorfds.map(|set| set as *mut FdSet).unwrap_or(null_mut()); - let timeout = timeout.map(|tv| tv as *mut TimeVal as *mut timeval) + let readfds = readfds.map(|set| set as *mut _ as *mut libc::fd_set).unwrap_or(null_mut()); + let writefds = writefds.map(|set| set as *mut _ as *mut libc::fd_set).unwrap_or(null_mut()); + let errorfds = errorfds.map(|set| set as *mut _ as *mut libc::fd_set).unwrap_or(null_mut()); + let timeout = timeout.map(|tv| tv as *mut _ as *mut libc::timeval) .unwrap_or(null_mut()); let res = unsafe { - ffi::select(nfds, readfds, writefds, errorfds, timeout) + libc::select(nfds, readfds, writefds, errorfds, timeout) }; Errno::result(res) @@ -166,6 +128,7 @@ where #[cfg(test)] mod tests { use super::*; + use std::os::unix::io::RawFd; use sys::time::{TimeVal, TimeValLike}; use unistd::{write, pipe}; @@ -174,7 +137,7 @@ mod tests { let mut fd_set = FdSet::new(); for i in 0..FD_SETSIZE { - assert!(!fd_set.contains(i)); + assert!(!fd_set.contains(i as RawFd)); } fd_set.insert(7); @@ -187,14 +150,14 @@ mod tests { let mut fd_set = FdSet::new(); for i in 0..FD_SETSIZE { - assert!(!fd_set.contains(i)); + assert!(!fd_set.contains(i as RawFd)); } fd_set.insert(7); fd_set.remove(7); for i in 0..FD_SETSIZE { - assert!(!fd_set.contains(i)); + assert!(!fd_set.contains(i as RawFd)); } } @@ -202,13 +165,13 @@ mod tests { fn fdset_clear() { let mut fd_set = FdSet::new(); fd_set.insert(1); - fd_set.insert(FD_SETSIZE / 2); - fd_set.insert(FD_SETSIZE - 1); + fd_set.insert((FD_SETSIZE / 2) as RawFd); + fd_set.insert((FD_SETSIZE - 1) as RawFd); fd_set.clear(); for i in 0..FD_SETSIZE { - assert!(!fd_set.contains(i)); + assert!(!fd_set.contains(i as RawFd)); } } |