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-rw-r--r--src/libstd/sys/unix/mutex.rs137
1 files changed, 0 insertions, 137 deletions
diff --git a/src/libstd/sys/unix/mutex.rs b/src/libstd/sys/unix/mutex.rs
deleted file mode 100644
index 45c600f75f5..00000000000
--- a/src/libstd/sys/unix/mutex.rs
+++ /dev/null
@@ -1,137 +0,0 @@
-use crate::cell::UnsafeCell;
-use crate::mem::MaybeUninit;
-
-pub struct Mutex {
-    inner: UnsafeCell<libc::pthread_mutex_t>,
-}
-
-#[inline]
-pub unsafe fn raw(m: &Mutex) -> *mut libc::pthread_mutex_t {
-    m.inner.get()
-}
-
-unsafe impl Send for Mutex {}
-unsafe impl Sync for Mutex {}
-
-#[allow(dead_code)] // sys isn't exported yet
-impl Mutex {
-    pub const fn new() -> Mutex {
-        // Might be moved to a different address, so it is better to avoid
-        // initialization of potentially opaque OS data before it landed.
-        // Be very careful using this newly constructed `Mutex`, reentrant
-        // locking is undefined behavior until `init` is called!
-        Mutex { inner: UnsafeCell::new(libc::PTHREAD_MUTEX_INITIALIZER) }
-    }
-    #[inline]
-    pub unsafe fn init(&mut self) {
-        // Issue #33770
-        //
-        // A pthread mutex initialized with PTHREAD_MUTEX_INITIALIZER will have
-        // a type of PTHREAD_MUTEX_DEFAULT, which has undefined behavior if you
-        // try to re-lock it from the same thread when you already hold a lock
-        // (https://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_mutex_init.html).
-        // This is the case even if PTHREAD_MUTEX_DEFAULT == PTHREAD_MUTEX_NORMAL
-        // (https://github.com/rust-lang/rust/issues/33770#issuecomment-220847521) -- in that
-        // case, `pthread_mutexattr_settype(PTHREAD_MUTEX_DEFAULT)` will of course be the same
-        // as setting it to `PTHREAD_MUTEX_NORMAL`, but not setting any mode will result in
-        // a Mutex where re-locking is UB.
-        //
-        // In practice, glibc takes advantage of this undefined behavior to
-        // implement hardware lock elision, which uses hardware transactional
-        // memory to avoid acquiring the lock. While a transaction is in
-        // progress, the lock appears to be unlocked. This isn't a problem for
-        // other threads since the transactional memory will abort if a conflict
-        // is detected, however no abort is generated when re-locking from the
-        // same thread.
-        //
-        // Since locking the same mutex twice will result in two aliasing &mut
-        // references, we instead create the mutex with type
-        // PTHREAD_MUTEX_NORMAL which is guaranteed to deadlock if we try to
-        // re-lock it from the same thread, thus avoiding undefined behavior.
-        let mut attr = MaybeUninit::<libc::pthread_mutexattr_t>::uninit();
-        let r = libc::pthread_mutexattr_init(attr.as_mut_ptr());
-        debug_assert_eq!(r, 0);
-        let r = libc::pthread_mutexattr_settype(attr.as_mut_ptr(), libc::PTHREAD_MUTEX_NORMAL);
-        debug_assert_eq!(r, 0);
-        let r = libc::pthread_mutex_init(self.inner.get(), attr.as_ptr());
-        debug_assert_eq!(r, 0);
-        let r = libc::pthread_mutexattr_destroy(attr.as_mut_ptr());
-        debug_assert_eq!(r, 0);
-    }
-    #[inline]
-    pub unsafe fn lock(&self) {
-        let r = libc::pthread_mutex_lock(self.inner.get());
-        debug_assert_eq!(r, 0);
-    }
-    #[inline]
-    pub unsafe fn unlock(&self) {
-        let r = libc::pthread_mutex_unlock(self.inner.get());
-        debug_assert_eq!(r, 0);
-    }
-    #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
-        libc::pthread_mutex_trylock(self.inner.get()) == 0
-    }
-    #[inline]
-    #[cfg(not(target_os = "dragonfly"))]
-    pub unsafe fn destroy(&self) {
-        let r = libc::pthread_mutex_destroy(self.inner.get());
-        debug_assert_eq!(r, 0);
-    }
-    #[inline]
-    #[cfg(target_os = "dragonfly")]
-    pub unsafe fn destroy(&self) {
-        let r = libc::pthread_mutex_destroy(self.inner.get());
-        // On DragonFly pthread_mutex_destroy() returns EINVAL if called on a
-        // mutex that was just initialized with libc::PTHREAD_MUTEX_INITIALIZER.
-        // Once it is used (locked/unlocked) or pthread_mutex_init() is called,
-        // this behaviour no longer occurs.
-        debug_assert!(r == 0 || r == libc::EINVAL);
-    }
-}
-
-pub struct ReentrantMutex {
-    inner: UnsafeCell<libc::pthread_mutex_t>,
-}
-
-unsafe impl Send for ReentrantMutex {}
-unsafe impl Sync for ReentrantMutex {}
-
-impl ReentrantMutex {
-    pub const unsafe fn uninitialized() -> ReentrantMutex {
-        ReentrantMutex { inner: UnsafeCell::new(libc::PTHREAD_MUTEX_INITIALIZER) }
-    }
-
-    pub unsafe fn init(&self) {
-        let mut attr = MaybeUninit::<libc::pthread_mutexattr_t>::uninit();
-        let result = libc::pthread_mutexattr_init(attr.as_mut_ptr());
-        debug_assert_eq!(result, 0);
-        let result =
-            libc::pthread_mutexattr_settype(attr.as_mut_ptr(), libc::PTHREAD_MUTEX_RECURSIVE);
-        debug_assert_eq!(result, 0);
-        let result = libc::pthread_mutex_init(self.inner.get(), attr.as_ptr());
-        debug_assert_eq!(result, 0);
-        let result = libc::pthread_mutexattr_destroy(attr.as_mut_ptr());
-        debug_assert_eq!(result, 0);
-    }
-
-    pub unsafe fn lock(&self) {
-        let result = libc::pthread_mutex_lock(self.inner.get());
-        debug_assert_eq!(result, 0);
-    }
-
-    #[inline]
-    pub unsafe fn try_lock(&self) -> bool {
-        libc::pthread_mutex_trylock(self.inner.get()) == 0
-    }
-
-    pub unsafe fn unlock(&self) {
-        let result = libc::pthread_mutex_unlock(self.inner.get());
-        debug_assert_eq!(result, 0);
-    }
-
-    pub unsafe fn destroy(&self) {
-        let result = libc::pthread_mutex_destroy(self.inner.get());
-        debug_assert_eq!(result, 0);
-    }
-}