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use super::*;
use crate::panic::{RefUnwindSafe, UnwindSafe};
use crate::sync::mpsc::sync_channel;
use crate::thread;
#[test]
fn stdout_unwind_safe() {
assert_unwind_safe::<Stdout>();
}
#[test]
fn stdoutlock_unwind_safe() {
assert_unwind_safe::<StdoutLock<'_>>();
assert_unwind_safe::<StdoutLock<'static>>();
}
#[test]
fn stderr_unwind_safe() {
assert_unwind_safe::<Stderr>();
}
#[test]
fn stderrlock_unwind_safe() {
assert_unwind_safe::<StderrLock<'_>>();
assert_unwind_safe::<StderrLock<'static>>();
}
fn assert_unwind_safe<T: UnwindSafe + RefUnwindSafe>() {}
#[test]
#[cfg_attr(target_os = "emscripten", ignore)]
fn panic_doesnt_poison() {
thread::spawn(|| {
let _a = stdin();
let _a = _a.lock();
let _a = stdout();
let _a = _a.lock();
let _a = stderr();
let _a = _a.lock();
panic!();
})
.join()
.unwrap_err();
let _a = stdin();
let _a = _a.lock();
let _a = stdout();
let _a = _a.lock();
let _a = stderr();
let _a = _a.lock();
}
#[test]
#[cfg_attr(target_os = "emscripten", ignore)]
fn test_lock_stderr() {
test_lock(stderr, || stderr().lock());
}
#[test]
#[cfg_attr(target_os = "emscripten", ignore)]
fn test_lock_stdin() {
test_lock(stdin, || stdin().lock());
}
#[test]
#[cfg_attr(target_os = "emscripten", ignore)]
fn test_lock_stdout() {
test_lock(stdout, || stdout().lock());
}
// Helper trait to make lock testing function generic.
trait Stdio<'a>: 'static
where
Self::Lock: 'a,
{
type Lock;
fn lock(&'a self) -> Self::Lock;
}
impl<'a> Stdio<'a> for Stderr {
type Lock = StderrLock<'a>;
fn lock(&'a self) -> StderrLock<'a> {
self.lock()
}
}
impl<'a> Stdio<'a> for Stdin {
type Lock = StdinLock<'a>;
fn lock(&'a self) -> StdinLock<'a> {
self.lock()
}
}
impl<'a> Stdio<'a> for Stdout {
type Lock = StdoutLock<'a>;
fn lock(&'a self) -> StdoutLock<'a> {
self.lock()
}
}
// Helper trait to make lock testing function generic.
trait StdioOwnedLock: 'static {}
impl StdioOwnedLock for StderrLock<'static> {}
impl StdioOwnedLock for StdinLock<'static> {}
impl StdioOwnedLock for StdoutLock<'static> {}
// Tests locking on stdio handles by starting two threads and checking that
// they block each other appropriately.
fn test_lock<T, U>(get_handle: fn() -> T, get_locked: fn() -> U)
where
T: for<'a> Stdio<'a>,
U: StdioOwnedLock,
{
// State enum to track different phases of the test, primarily when
// each lock is acquired and released.
#[derive(Debug, PartialEq)]
enum State {
Start1,
Acquire1,
Start2,
Release1,
Acquire2,
Release2,
}
use State::*;
// Logging vector to be checked to make sure lock acquisitions and
// releases happened in the correct order.
let log = Arc::new(Mutex::new(Vec::new()));
let ((tx1, rx1), (tx2, rx2)) = (sync_channel(0), sync_channel(0));
let th1 = {
let (log, tx) = (Arc::clone(&log), tx1);
thread::spawn(move || {
log.lock().unwrap().push(Start1);
let handle = get_handle();
{
let locked = handle.lock();
log.lock().unwrap().push(Acquire1);
tx.send(Acquire1).unwrap(); // notify of acquisition
tx.send(Release1).unwrap(); // wait for release command
log.lock().unwrap().push(Release1);
}
tx.send(Acquire1).unwrap(); // wait for th2 acquire
{
let locked = handle.lock();
log.lock().unwrap().push(Acquire1);
}
log.lock().unwrap().push(Release1);
})
};
let th2 = {
let (log, tx) = (Arc::clone(&log), tx2);
thread::spawn(move || {
tx.send(Start2).unwrap(); // wait for start command
let locked = get_locked();
log.lock().unwrap().push(Acquire2);
tx.send(Acquire2).unwrap(); // notify of acquisition
tx.send(Release2).unwrap(); // wait for release command
log.lock().unwrap().push(Release2);
})
};
assert_eq!(rx1.recv().unwrap(), Acquire1); // wait for th1 acquire
log.lock().unwrap().push(Start2);
assert_eq!(rx2.recv().unwrap(), Start2); // block th2
assert_eq!(rx1.recv().unwrap(), Release1); // release th1
assert_eq!(rx2.recv().unwrap(), Acquire2); // wait for th2 acquire
assert_eq!(rx1.recv().unwrap(), Acquire1); // block th1
assert_eq!(rx2.recv().unwrap(), Release2); // release th2
th2.join().unwrap();
th1.join().unwrap();
assert_eq!(
*log.lock().unwrap(),
[Start1, Acquire1, Start2, Release1, Acquire2, Release2, Acquire1, Release1]
);
}
|
