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use lock_api::{self, GetThreadId};
use raw_mutex::RawMutex;
pub struct RawThreadId;
unsafe impl GetThreadId for RawThreadId {
const INIT: RawThreadId = RawThreadId;
fn nonzero_thread_id(&self) -> usize {
thread_local!(static KEY: u8 = unsafe { ::std::mem::uninitialized() });
KEY.with(|x| x as *const _ as usize)
}
}
pub type ReentrantMutex<T> = lock_api::ReentrantMutex<RawMutex, RawThreadId, T>;
pub type ReentrantMutexGuard<'a, T> =
lock_api::ReentrantMutexGuard<'a, RawMutex, RawThreadId, T>;
pub type MappedReentrantMutexGuard<'a, T> =
lock_api::MappedReentrantMutexGuard<'a, RawMutex, RawThreadId, T>;
#[cfg(test)]
mod tests {
use std::cell::RefCell;
use std::sync::Arc;
use std::thread;
use ReentrantMutex;
#[test]
fn smoke() {
let m = ReentrantMutex::new(());
{
let a = m.lock();
{
let b = m.lock();
{
let c = m.lock();
assert_eq!(*c, ());
}
assert_eq!(*b, ());
}
assert_eq!(*a, ());
}
}
#[test]
fn is_mutex() {
let m = Arc::new(ReentrantMutex::new(RefCell::new(0)));
let m2 = m.clone();
let lock = m.lock();
let child = thread::spawn(move || {
let lock = m2.lock();
assert_eq!(*lock.borrow(), 4950);
});
for i in 0..100 {
let lock = m.lock();
*lock.borrow_mut() += i;
}
drop(lock);
child.join().unwrap();
}
#[test]
fn trylock_works() {
let m = Arc::new(ReentrantMutex::new(()));
let m2 = m.clone();
let _lock = m.try_lock();
let _lock2 = m.try_lock();
thread::spawn(move || {
let lock = m2.try_lock();
assert!(lock.is_none());
}).join()
.unwrap();
let _lock3 = m.try_lock();
}
#[test]
fn test_reentrant_mutex_debug() {
let mutex = ReentrantMutex::new(vec![0u8, 10]);
assert_eq!(format!("{:?}", mutex), "ReentrantMutex { data: [0, 10] }");
assert_eq!(
format!("{:#?}", mutex),
"ReentrantMutex {
data: [
0,
10
]
}"
);
}
}