Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Avoid writes without any data in Write::write_all_vectored #74088

Merged
merged 1 commit into from
Jul 27, 2020
Merged
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 5 additions & 2 deletions src/libstd/io/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -251,7 +251,6 @@

use crate::cmp;
use crate::fmt;
use crate::mem;
use crate::memchr;
use crate::ops::{Deref, DerefMut};
use crate::ptr;
Expand Down Expand Up @@ -1435,12 +1434,15 @@ pub trait Write {
/// ```
#[unstable(feature = "write_all_vectored", issue = "70436")]
fn write_all_vectored(&mut self, mut bufs: &mut [IoSlice<'_>]) -> Result<()> {
// Guarantee that bufs is empty if it contains no data,
// to avoid calling write_vectored if there is no data to be written.
bufs = IoSlice::advance(bufs, 0);
tmiasko marked this conversation as resolved.
Show resolved Hide resolved
while !bufs.is_empty() {
match self.write_vectored(bufs) {
Ok(0) => {
return Err(Error::new(ErrorKind::WriteZero, "failed to write whole buffer"));
}
Ok(n) => bufs = IoSlice::advance(mem::take(&mut bufs), n),
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It makes me happy this is possible now :)

Ok(n) => bufs = IoSlice::advance(bufs, n),
Err(ref e) if e.kind() == ErrorKind::Interrupted => {}
Err(e) => return Err(e),
}
Expand Down Expand Up @@ -2958,6 +2960,7 @@ mod tests {
#[rustfmt::skip] // Becomes unreadable otherwise.
let tests: Vec<(_, &'static [u8])> = vec![
(vec![], &[]),
(vec![IoSlice::new(&[]), IoSlice::new(&[])], &[]),
(vec![IoSlice::new(&[1])], &[1]),
(vec![IoSlice::new(&[1, 2])], &[1, 2]),
(vec![IoSlice::new(&[1, 2, 3])], &[1, 2, 3]),
Expand Down