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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:47:55 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:47:55 +0000 |
commit | 2aadc03ef15cb5ca5cc2af8a7c08e070742f0ac4 (patch) | |
tree | 033cc839730fda84ff08db877037977be94e5e3a /crates/cargo-util/src/read2.rs | |
parent | Initial commit. (diff) | |
download | cargo-2aadc03ef15cb5ca5cc2af8a7c08e070742f0ac4.tar.xz cargo-2aadc03ef15cb5ca5cc2af8a7c08e070742f0ac4.zip |
Adding upstream version 0.70.1+ds1.upstream/0.70.1+ds1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'crates/cargo-util/src/read2.rs')
-rw-r--r-- | crates/cargo-util/src/read2.rs | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/crates/cargo-util/src/read2.rs b/crates/cargo-util/src/read2.rs new file mode 100644 index 0000000..742dc1d --- /dev/null +++ b/crates/cargo-util/src/read2.rs @@ -0,0 +1,178 @@ +pub use self::imp::read2; + +#[cfg(unix)] +mod imp { + use std::io; + use std::io::prelude::*; + use std::mem; + use std::os::unix::prelude::*; + use std::process::{ChildStderr, ChildStdout}; + + pub fn read2( + mut out_pipe: ChildStdout, + mut err_pipe: ChildStderr, + data: &mut dyn FnMut(bool, &mut Vec<u8>, bool), + ) -> io::Result<()> { + unsafe { + libc::fcntl(out_pipe.as_raw_fd(), libc::F_SETFL, libc::O_NONBLOCK); + libc::fcntl(err_pipe.as_raw_fd(), libc::F_SETFL, libc::O_NONBLOCK); + } + + let mut out_done = false; + let mut err_done = false; + let mut out = Vec::new(); + let mut err = Vec::new(); + + let mut fds: [libc::pollfd; 2] = unsafe { mem::zeroed() }; + fds[0].fd = out_pipe.as_raw_fd(); + fds[0].events = libc::POLLIN; + fds[1].fd = err_pipe.as_raw_fd(); + fds[1].events = libc::POLLIN; + let mut nfds = 2; + let mut errfd = 1; + + while nfds > 0 { + // wait for either pipe to become readable using `select` + let r = unsafe { libc::poll(fds.as_mut_ptr(), nfds, -1) }; + if r == -1 { + let err = io::Error::last_os_error(); + if err.kind() == io::ErrorKind::Interrupted { + continue; + } + return Err(err); + } + + // Read as much as we can from each pipe, ignoring EWOULDBLOCK or + // EAGAIN. If we hit EOF, then this will happen because the underlying + // reader will return Ok(0), in which case we'll see `Ok` ourselves. In + // this case we flip the other fd back into blocking mode and read + // whatever's leftover on that file descriptor. + let handle = |res: io::Result<_>| match res { + Ok(_) => Ok(true), + Err(e) => { + if e.kind() == io::ErrorKind::WouldBlock { + Ok(false) + } else { + Err(e) + } + } + }; + if !err_done && fds[errfd].revents != 0 && handle(err_pipe.read_to_end(&mut err))? { + err_done = true; + nfds -= 1; + } + data(false, &mut err, err_done); + if !out_done && fds[0].revents != 0 && handle(out_pipe.read_to_end(&mut out))? { + out_done = true; + fds[0].fd = err_pipe.as_raw_fd(); + errfd = 0; + nfds -= 1; + } + data(true, &mut out, out_done); + } + Ok(()) + } +} + +#[cfg(windows)] +mod imp { + use std::io; + use std::os::windows::prelude::*; + use std::process::{ChildStderr, ChildStdout}; + use std::slice; + + use miow::iocp::{CompletionPort, CompletionStatus}; + use miow::pipe::NamedPipe; + use miow::Overlapped; + use windows_sys::Win32::Foundation::ERROR_BROKEN_PIPE; + + struct Pipe<'a> { + dst: &'a mut Vec<u8>, + overlapped: Overlapped, + pipe: NamedPipe, + done: bool, + } + + pub fn read2( + out_pipe: ChildStdout, + err_pipe: ChildStderr, + data: &mut dyn FnMut(bool, &mut Vec<u8>, bool), + ) -> io::Result<()> { + let mut out = Vec::new(); + let mut err = Vec::new(); + + let port = CompletionPort::new(1)?; + port.add_handle(0, &out_pipe)?; + port.add_handle(1, &err_pipe)?; + + unsafe { + let mut out_pipe = Pipe::new(out_pipe, &mut out); + let mut err_pipe = Pipe::new(err_pipe, &mut err); + + out_pipe.read()?; + err_pipe.read()?; + + let mut status = [CompletionStatus::zero(), CompletionStatus::zero()]; + + while !out_pipe.done || !err_pipe.done { + for status in port.get_many(&mut status, None)? { + if status.token() == 0 { + out_pipe.complete(status); + data(true, out_pipe.dst, out_pipe.done); + out_pipe.read()?; + } else { + err_pipe.complete(status); + data(false, err_pipe.dst, err_pipe.done); + err_pipe.read()?; + } + } + } + + Ok(()) + } + } + + impl<'a> Pipe<'a> { + unsafe fn new<P: IntoRawHandle>(p: P, dst: &'a mut Vec<u8>) -> Pipe<'a> { + Pipe { + dst, + pipe: NamedPipe::from_raw_handle(p.into_raw_handle()), + overlapped: Overlapped::zero(), + done: false, + } + } + + unsafe fn read(&mut self) -> io::Result<()> { + let dst = slice_to_end(self.dst); + match self.pipe.read_overlapped(dst, self.overlapped.raw()) { + Ok(_) => Ok(()), + Err(e) => { + if e.raw_os_error() == Some(ERROR_BROKEN_PIPE as i32) { + self.done = true; + Ok(()) + } else { + Err(e) + } + } + } + } + + unsafe fn complete(&mut self, status: &CompletionStatus) { + let prev = self.dst.len(); + self.dst.set_len(prev + status.bytes_transferred() as usize); + if status.bytes_transferred() == 0 { + self.done = true; + } + } + } + + unsafe fn slice_to_end(v: &mut Vec<u8>) -> &mut [u8] { + if v.capacity() == 0 { + v.reserve(16); + } + if v.capacity() == v.len() { + v.reserve(1); + } + slice::from_raw_parts_mut(v.as_mut_ptr().add(v.len()), v.capacity() - v.len()) + } +} |