Skip to content

Commit

Permalink
use BOOL for TCP_NODELAY setsockopt value on Windows
Browse files Browse the repository at this point in the history
This issue was found by the Wine project and mitigated there [1].

Windows' documented interface for `setsockopt` expects a `BOOL` (a
`typedef` for `int`) for `TCP_NODELAY` [2]. Windows is forgiving and
will accept any positive length and interpret the first byte of
`*option_value` as the value, so this bug does not affect Windows
itself, but does affect systems implementing Windows' interface more
strictly, such as Wine. Wine was previously passing this through to the
host's `setsockopt`, where, e.g., Linux requires that `option_len` be
correct for the chosen option, and `TCP_NODELAY` expects an `int`.

[1]: https://source.winehq.org/git/wine.git/commit/d6ea38f32dfd3edbe107a255c37e9f7f3da06ae7
[2]: https://docs.microsoft.com/en-us/windows/win32/api/winsock/nf-winsock-setsockopt
  • Loading branch information
chrisnc committed Feb 21, 2022
1 parent f2ebd0a commit b02698c
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions library/std/src/sys/windows/net.rs
Original file line number Diff line number Diff line change
Expand Up @@ -407,11 +407,11 @@ impl Socket {
}

pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
net::setsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY, nodelay as c::BYTE)
net::setsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY, nodelay as c::BOOL)
}

pub fn nodelay(&self) -> io::Result<bool> {
let raw: c::BYTE = net::getsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY)?;
let raw: c::BOOL = net::getsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY)?;
Ok(raw != 0)
}

Expand Down

0 comments on commit b02698c

Please sign in to comment.