rust-lang/rust
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Change SIGPIPE ui from #[unix_sigpipe = "..."] to -Zon-broken-pipe=...

Browse Source 
In the stabilization attempt of `#[unix_sigpipe = "sig_dfl"]`, a concern
was raised related to using a language attribute for the feature: Long
term, we want `fn lang_start()` to be definable by any crate, not just
libstd. Having a special language attribute in that case becomes
awkward.

So as a first step towards towards the next stabilization attempt, this
PR changes the `#[unix_sigpipe = "..."]` attribute to a compiler flag
`-Zon-broken-pipe=...` to remove that concern, since now the language
is not "contaminated" by this feature.

Another point was also raised, namely that the ui should not leak
**how** it does things, but rather what the **end effect** is. The new
flag uses the proposed naming. This is of course something that can be
iterated on further before stabilization.
This commit is contained in:
Martin Nordholts
2024-04-28 18:02:21 +02:00
parent e27af2917b
commit cde0cde151
64 changed files with 203 additions and 372 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
library/std/src/sys/pal/unix/mod.rs
View File

@@ -55,8 +55,8 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
// want!
//
// Hence, we set SIGPIPE to ignore when the program starts up in order
// to prevent this problem. Add `#[unix_sigpipe = "..."]` above `fn main()` to
// alter this behavior.
// to prevent this problem. Use `-Zon-broken-pipe=...` to alter this
// behavior.
reset_sigpipe(sigpipe);
stack_overflow::init();
@@ -194,7 +194,7 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
_ => unreachable!(),
};
if sigpipe_attr_specified {
UNIX_SIGPIPE_ATTR_SPECIFIED.store(true, crate::sync::atomic::Ordering::Relaxed);
ON_BROKEN_PIPE_FLAG_USED.store(true, crate::sync::atomic::Ordering::Relaxed);
}
if let Some(handler) = handler {
rtassert!(signal(libc::SIGPIPE, handler) != libc::SIG_ERR);
@@ -214,7 +214,7 @@ pub unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) {
target_os = "fuchsia",
target_os = "horizon",
)))]
static UNIX_SIGPIPE_ATTR_SPECIFIED: crate::sync::atomic::AtomicBool =
static ON_BROKEN_PIPE_FLAG_USED: crate::sync::atomic::AtomicBool =
crate::sync::atomic::AtomicBool::new(false);
#[cfg(not(any(
@@ -223,8 +223,8 @@ static UNIX_SIGPIPE_ATTR_SPECIFIED: crate::sync::atomic::AtomicBool =
target_os = "fuchsia",
target_os = "horizon",
)))]
pub(crate) fn unix_sigpipe_attr_specified() -> bool {
UNIX_SIGPIPE_ATTR_SPECIFIED.load(crate::sync::atomic::Ordering::Relaxed)
pub(crate) fn on_broken_pipe_flag_used() -> bool {
ON_BROKEN_PIPE_FLAG_USED.load(crate::sync::atomic::Ordering::Relaxed)
}
// SAFETY: must be called only once during runtime cleanup.

18
library/std/src/sys/pal/unix/process/process_unix.rs
View File

@@ -353,11 +353,11 @@ impl Command {
// Inherit the signal mask from the parent rather than resetting it (i.e. do not call
// pthread_sigmask).
// If #[unix_sigpipe] is specified, don't reset SIGPIPE to SIG_DFL.
// If #[unix_sigpipe] is not specified, reset SIGPIPE to SIG_DFL for backward compatibility.
// If -Zon-broken-pipe is used, don't reset SIGPIPE to SIG_DFL.
// If -Zon-broken-pipe is not used, reset SIGPIPE to SIG_DFL for backward compatibility.
//
// #[unix_sigpipe] is an opportunity to change the default here.
if !crate::sys::pal::unix_sigpipe_attr_specified() {
// -Zon-broken-pipe is an opportunity to change the default here.
if !crate::sys::pal::on_broken_pipe_flag_used() {
#[cfg(target_os = "android")] // see issue #88585
{
let mut action: libc::sigaction = mem::zeroed();
@@ -455,7 +455,7 @@ impl Command {
) -> io::Result<Option<Process>> {
use crate::mem::MaybeUninit;
use crate::sys::weak::weak;
use crate::sys::{self, cvt_nz, unix_sigpipe_attr_specified};
use crate::sys::{self, cvt_nz, on_broken_pipe_flag_used};
if self.get_gid().is_some()
|| self.get_uid().is_some()
@@ -617,11 +617,11 @@ impl Command {
// Inherit the signal mask from this process rather than resetting it (i.e. do not call
// posix_spawnattr_setsigmask).
// If #[unix_sigpipe] is specified, don't reset SIGPIPE to SIG_DFL.
// If #[unix_sigpipe] is not specified, reset SIGPIPE to SIG_DFL for backward compatibility.
// If -Zon-broken-pipe is used, don't reset SIGPIPE to SIG_DFL.
// If -Zon-broken-pipe is not used, reset SIGPIPE to SIG_DFL for backward compatibility.
//
// #[unix_sigpipe] is an opportunity to change the default here.
if !unix_sigpipe_attr_specified() {
// -Zon-broken-pipe is an opportunity to change the default here.
if !on_broken_pipe_flag_used() {
let mut default_set = MaybeUninit::<libc::sigset_t>::uninit();
cvt(sigemptyset(default_set.as_mut_ptr()))?;
cvt(sigaddset(default_set.as_mut_ptr(), libc::SIGPIPE))?;