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// Silence invalid warnings due to rust-lang/rust#16719
#![allow(improper_ctypes)]
use {Errno, Result};
use libc::{self, c_int, c_void, size_t, off_t};
use std::marker::PhantomData;
use std::os::unix::io::RawFd;
pub fn writev(fd: RawFd, iov: &[IoVec<&[u8]>]) -> Result<usize> {
let res = unsafe { libc::writev(fd, iov.as_ptr() as *const libc::iovec, iov.len() as c_int) };
Errno::result(res).map(|r| r as usize)
}
pub fn readv(fd: RawFd, iov: &mut [IoVec<&mut [u8]>]) -> Result<usize> {
let res = unsafe { libc::readv(fd, iov.as_ptr() as *const libc::iovec, iov.len() as c_int) };
Errno::result(res).map(|r| r as usize)
}
#[cfg(target_os = "linux")]
pub fn pwritev(fd: RawFd, iov: &[IoVec<&[u8]>],
offset: off_t) -> Result<usize> {
let res = unsafe {
libc::pwritev(fd, iov.as_ptr() as *const libc::iovec, iov.len() as c_int, offset)
};
Errno::result(res).map(|r| r as usize)
}
#[cfg(target_os = "linux")]
pub fn preadv(fd: RawFd, iov: &mut [IoVec<&mut [u8]>],
offset: off_t) -> Result<usize> {
let res = unsafe {
libc::preadv(fd, iov.as_ptr() as *const libc::iovec, iov.len() as c_int, offset)
};
Errno::result(res).map(|r| r as usize)
}
pub fn pwrite(fd: RawFd, buf: &[u8], offset: off_t) -> Result<usize> {
let res = unsafe {
libc::pwrite(fd, buf.as_ptr() as *const c_void, buf.len() as size_t,
offset)
};
Errno::result(res).map(|r| r as usize)
}
pub fn pread(fd: RawFd, buf: &mut [u8], offset: off_t) -> Result<usize>{
let res = unsafe {
libc::pread(fd, buf.as_mut_ptr() as *mut c_void, buf.len() as size_t,
offset)
};
Errno::result(res).map(|r| r as usize)
}
#[repr(C)]
pub struct IoVec<T>(libc::iovec, PhantomData<T>);
impl<T> IoVec<T> {
#[inline]
pub fn as_slice<'a>(&'a self) -> &'a [u8] {
use std::slice;
unsafe {
slice::from_raw_parts(
self.0.iov_base as *const u8,
self.0.iov_len as usize)
}
}
}
impl<'a> IoVec<&'a [u8]> {
pub fn from_slice(buf: &'a [u8]) -> IoVec<&'a [u8]> {
IoVec(libc::iovec {
iov_base: buf.as_ptr() as *mut c_void,
iov_len: buf.len() as size_t,
}, PhantomData)
}
}
impl<'a> IoVec<&'a mut [u8]> {
pub fn from_mut_slice(buf: &'a mut [u8]) -> IoVec<&'a mut [u8]> {
IoVec(libc::iovec {
iov_base: buf.as_ptr() as *mut c_void,
iov_len: buf.len() as size_t,
}, PhantomData)
}
}
#[test]
pub fn test_size_of_io_vec() {
use nixtest;
nixtest::assert_size_of::<IoVec<&[u8]>>("iovec");
}
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