use std::{
ffi::c_void,
fmt,
io::{self, Write},
};
use windows::Win32::{
Foundation::{CloseHandle, HANDLE},
Storage::FileSystem::{FlushFileBuffers, WriteFile},
};
use crate::{error::Error, util::clone_handle};
pub struct PipeWriter {
handle: HANDLE,
}
impl PipeWriter {
pub fn new(handle: HANDLE) -> Self {
Self { handle }
}
pub fn try_clone(&self) -> Result<Self, Error> {
clone_handle(self.handle).map_err(Into::into).map(Self::new)
}
}
impl Write for PipeWriter {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
write_to_pipe(self.handle, buf)
}
fn flush(&mut self) -> io::Result<()> {
flush_pipe(self.handle)
}
}
impl Drop for PipeWriter {
fn drop(&mut self) {
unsafe {
CloseHandle(self.handle).ok().unwrap();
}
}
}
impl From<PipeWriter> for std::fs::File {
fn from(pipe: PipeWriter) -> Self {
use std::os::windows::io::FromRawHandle;
let pipe = std::mem::ManuallyDrop::new(pipe);
unsafe { std::fs::File::from_raw_handle(pipe.handle.0 as _) }
}
}
impl fmt::Debug for PipeWriter {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("PipeWriter")
.field("handle", &(self.handle.0))
.field("handle(ptr)", &(self.handle.0 as *const c_void))
.finish()
}
}
unsafe impl Send for PipeWriter {}
unsafe impl Sync for PipeWriter {}
fn write_to_pipe(h: HANDLE, buf: &[u8]) -> io::Result<usize> {
let mut n = 0;
unsafe {
WriteFile(h, Some(buf), Some(&mut n), None)?;
}
Ok(n as usize)
}
fn flush_pipe(h: HANDLE) -> Result<(), io::Error> {
unsafe {
FlushFileBuffers(h)?;
}
Ok(())
}