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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /third_party/rust/nix/src/sys/uio.rs
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/nix/src/sys/uio.rs')
-rw-r--r--third_party/rust/nix/src/sys/uio.rs225
1 files changed, 225 insertions, 0 deletions
diff --git a/third_party/rust/nix/src/sys/uio.rs b/third_party/rust/nix/src/sys/uio.rs
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+//! Vectored I/O
+
+use crate::errno::Errno;
+use crate::Result;
+use libc::{self, c_int, c_void, off_t, size_t};
+use std::io::{IoSlice, IoSliceMut};
+use std::os::unix::io::{AsFd, AsRawFd};
+
+/// Low-level vectored write to a raw file descriptor
+///
+/// See also [writev(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/writev.html)
+pub fn writev<Fd: AsFd>(fd: Fd, iov: &[IoSlice<'_>]) -> Result<usize> {
+ // SAFETY: to quote the documentation for `IoSlice`:
+ //
+ // [IoSlice] is semantically a wrapper around a &[u8], but is
+ // guaranteed to be ABI compatible with the iovec type on Unix
+ // platforms.
+ //
+ // Because it is ABI compatible, a pointer cast here is valid
+ let res = unsafe {
+ libc::writev(fd.as_fd().as_raw_fd(), iov.as_ptr() as *const libc::iovec, iov.len() as c_int)
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+
+/// Low-level vectored read from a raw file descriptor
+///
+/// See also [readv(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/readv.html)
+// Clippy doesn't know that we need to pass iov mutably only because the
+// mutation happens after converting iov to a pointer
+#[allow(clippy::needless_pass_by_ref_mut)]
+pub fn readv<Fd: AsFd>(fd: Fd, iov: &mut [IoSliceMut<'_>]) -> Result<usize> {
+ // SAFETY: same as in writev(), IoSliceMut is ABI-compatible with iovec
+ let res = unsafe {
+ libc::readv(fd.as_fd().as_raw_fd(), iov.as_ptr() as *const libc::iovec, iov.len() as c_int)
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+
+/// Write to `fd` at `offset` from buffers in `iov`.
+///
+/// Buffers in `iov` will be written in order until all buffers have been written
+/// or an error occurs. The file offset is not changed.
+///
+/// See also: [`writev`](fn.writev.html) and [`pwrite`](fn.pwrite.html)
+#[cfg(not(any(target_os = "redox", target_os = "haiku")))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
+pub fn pwritev<Fd: AsFd>(fd: Fd, iov: &[IoSlice<'_>], offset: off_t) -> Result<usize> {
+ #[cfg(target_env = "uclibc")]
+ let offset = offset as libc::off64_t; // uclibc doesn't use off_t
+
+ // SAFETY: same as in writev()
+ let res = unsafe {
+ libc::pwritev(
+ fd.as_fd().as_raw_fd(),
+ iov.as_ptr() as *const libc::iovec,
+ iov.len() as c_int,
+ offset,
+ )
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+
+/// Read from `fd` at `offset` filling buffers in `iov`.
+///
+/// Buffers in `iov` will be filled in order until all buffers have been filled,
+/// no more bytes are available, or an error occurs. The file offset is not
+/// changed.
+///
+/// See also: [`readv`](fn.readv.html) and [`pread`](fn.pread.html)
+#[cfg(not(any(target_os = "redox", target_os = "haiku")))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
+// Clippy doesn't know that we need to pass iov mutably only because the
+// mutation happens after converting iov to a pointer
+#[allow(clippy::needless_pass_by_ref_mut)]
+pub fn preadv<Fd: AsFd>(
+ fd: Fd,
+ iov: &mut [IoSliceMut<'_>],
+ offset: off_t,
+) -> Result<usize> {
+ #[cfg(target_env = "uclibc")]
+ let offset = offset as libc::off64_t; // uclibc doesn't use off_t
+
+ // SAFETY: same as in readv()
+ let res = unsafe {
+ libc::preadv(
+ fd.as_fd().as_raw_fd(),
+ iov.as_ptr() as *const libc::iovec,
+ iov.len() as c_int,
+ offset,
+ )
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+
+/// Low-level write to a file, with specified offset.
+///
+/// See also [pwrite(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/pwrite.html)
+// TODO: move to unistd
+pub fn pwrite<Fd: AsFd>(fd: Fd, buf: &[u8], offset: off_t) -> Result<usize> {
+ let res = unsafe {
+ libc::pwrite(
+ fd.as_fd().as_raw_fd(),
+ buf.as_ptr() as *const c_void,
+ buf.len() as size_t,
+ offset,
+ )
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+
+/// Low-level read from a file, with specified offset.
+///
+/// See also [pread(2)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/pread.html)
+// TODO: move to unistd
+pub fn pread<Fd: AsFd>(fd: Fd, buf: &mut [u8], offset: off_t) -> Result<usize> {
+ let res = unsafe {
+ libc::pread(
+ fd.as_fd().as_raw_fd(),
+ buf.as_mut_ptr() as *mut c_void,
+ buf.len() as size_t,
+ offset,
+ )
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+
+/// A slice of memory in a remote process, starting at address `base`
+/// and consisting of `len` bytes.
+///
+/// This is the same underlying C structure as `IoSlice`,
+/// except that it refers to memory in some other process, and is
+/// therefore not represented in Rust by an actual slice as `IoSlice` is. It
+/// is used with [`process_vm_readv`](fn.process_vm_readv.html)
+/// and [`process_vm_writev`](fn.process_vm_writev.html).
+#[cfg(any(target_os = "linux", target_os = "android"))]
+#[cfg_attr(docsrs, doc(cfg(all())))]
+#[repr(C)]
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub struct RemoteIoVec {
+ /// The starting address of this slice (`iov_base`).
+ pub base: usize,
+ /// The number of bytes in this slice (`iov_len`).
+ pub len: usize,
+}
+
+feature! {
+#![feature = "process"]
+
+/// Write data directly to another process's virtual memory
+/// (see [`process_vm_writev`(2)]).
+///
+/// `local_iov` is a list of [`IoSlice`]s containing the data to be written,
+/// and `remote_iov` is a list of [`RemoteIoVec`]s identifying where the
+/// data should be written in the target process. On success, returns the
+/// number of bytes written, which will always be a whole
+/// number of `remote_iov` chunks.
+///
+/// This requires the same permissions as debugging the process using
+/// [ptrace]: you must either be a privileged process (with
+/// `CAP_SYS_PTRACE`), or you must be running as the same user as the
+/// target process and the OS must have unprivileged debugging enabled.
+///
+/// This function is only available on Linux and Android(SDK23+).
+///
+/// [`process_vm_writev`(2)]: https://man7.org/linux/man-pages/man2/process_vm_writev.2.html
+/// [ptrace]: ../ptrace/index.html
+/// [`IoSlice`]: https://doc.rust-lang.org/std/io/struct.IoSlice.html
+/// [`RemoteIoVec`]: struct.RemoteIoVec.html
+#[cfg(all(any(target_os = "linux", target_os = "android"), not(target_env = "uclibc")))]
+pub fn process_vm_writev(
+ pid: crate::unistd::Pid,
+ local_iov: &[IoSlice<'_>],
+ remote_iov: &[RemoteIoVec]) -> Result<usize>
+{
+ let res = unsafe {
+ libc::process_vm_writev(pid.into(),
+ local_iov.as_ptr() as *const libc::iovec, local_iov.len() as libc::c_ulong,
+ remote_iov.as_ptr() as *const libc::iovec, remote_iov.len() as libc::c_ulong, 0)
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+
+/// Read data directly from another process's virtual memory
+/// (see [`process_vm_readv`(2)]).
+///
+/// `local_iov` is a list of [`IoSliceMut`]s containing the buffer to copy
+/// data into, and `remote_iov` is a list of [`RemoteIoVec`]s identifying
+/// where the source data is in the target process. On success,
+/// returns the number of bytes written, which will always be a whole
+/// number of `remote_iov` chunks.
+///
+/// This requires the same permissions as debugging the process using
+/// [`ptrace`]: you must either be a privileged process (with
+/// `CAP_SYS_PTRACE`), or you must be running as the same user as the
+/// target process and the OS must have unprivileged debugging enabled.
+///
+/// This function is only available on Linux and Android(SDK23+).
+///
+/// [`process_vm_readv`(2)]: https://man7.org/linux/man-pages/man2/process_vm_readv.2.html
+/// [`ptrace`]: ../ptrace/index.html
+/// [`IoSliceMut`]: https://doc.rust-lang.org/std/io/struct.IoSliceMut.html
+/// [`RemoteIoVec`]: struct.RemoteIoVec.html
+#[cfg(all(any(target_os = "linux", target_os = "android"), not(target_env = "uclibc")))]
+pub fn process_vm_readv(
+ pid: crate::unistd::Pid,
+ local_iov: &mut [IoSliceMut<'_>],
+ remote_iov: &[RemoteIoVec]) -> Result<usize>
+{
+ let res = unsafe {
+ libc::process_vm_readv(pid.into(),
+ local_iov.as_ptr() as *const libc::iovec, local_iov.len() as libc::c_ulong,
+ remote_iov.as_ptr() as *const libc::iovec, remote_iov.len() as libc::c_ulong, 0)
+ };
+
+ Errno::result(res).map(|r| r as usize)
+}
+}