std: Rename unstable::mutex::Mutex to StaticNativeMutex.

This better reflects its purpose and design.

Author: huonw

src/libgreen/sched.rs

@@ -15,7 +15,7 @@ use std::rt::rtio::{RemoteCallback, PausableIdleCallback, Callback, EventLoop};
 use std::rt::task::BlockedTask;
 use std::rt::task::Task;
 use std::sync::deque;
-use std::unstable::mutex::Mutex;
+use std::unstable::mutex::StaticNativeMutex;
 use std::unstable::raw;
 
 use TaskState;
@@ -764,7 +764,7 @@ impl Scheduler {
         // to it, but we're guaranteed that the task won't exit until we've
         // unlocked the lock so there's no worry of this memory going away.
         let cur = self.change_task_context(cur, next, |sched, mut task| {
-            let lock: *mut Mutex = &mut task.nasty_deschedule_lock;
+            let lock: *mut StaticNativeMutex = &mut task.nasty_deschedule_lock;
             unsafe {
                 let _guard = (*lock).lock();
                 f(sched, BlockedTask::block(task.swap()));
@@ -1453,8 +1453,8 @@ mod test {
 
     #[test]
     fn test_spawn_sched_blocking() {
-        use std::unstable::mutex::{Mutex, MUTEX_INIT};
-        static mut LOCK: Mutex = MUTEX_INIT;
+        use std::unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
+        static mut LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
 
         // Testing that a task in one scheduler can block in foreign code
         // without affecting other schedulers

src/libgreen/task.rs

@@ -25,7 +25,7 @@ use std::rt::local::Local;
 use std::rt::rtio;
 use std::rt::task::{Task, BlockedTask, SendMessage};
 use std::task::TaskOpts;
-use std::unstable::mutex::Mutex;
+use std::unstable::mutex::StaticNativeMutex;
 use std::unstable::raw;
 
 use context::Context;
@@ -65,7 +65,7 @@ pub struct GreenTask {
     pool_id: uint,
 
     // See the comments in the scheduler about why this is necessary
-    nasty_deschedule_lock: Mutex,
+    nasty_deschedule_lock: StaticNativeMutex,
 }
 
 pub enum TaskType {
@@ -163,7 +163,7 @@ impl GreenTask {
             task_type: task_type,
             sched: None,
             handle: None,
-            nasty_deschedule_lock: unsafe { Mutex::new() },
+            nasty_deschedule_lock: unsafe { StaticNativeMutex::new() },
             task: Some(~Task::new()),
         }
     }
@@ -322,7 +322,7 @@ impl GreenTask {
     // uncontended except for when the task is rescheduled).
     fn reawaken_remotely(mut ~self) {
         unsafe {
-            let mtx = &mut self.nasty_deschedule_lock as *mut Mutex;
+            let mtx = &mut self.nasty_deschedule_lock as *mut StaticNativeMutex;
             let handle = self.handle.get_mut_ref() as *mut SchedHandle;
             let _guard = (*mtx).lock();
             (*handle).send(RunOnce(self));

src/libnative/bookkeeping.rs

@@ -17,10 +17,10 @@
 //! The green counterpart for this is bookkeeping on sched pools.
 
 use std::sync::atomics;
-use std::unstable::mutex::{Mutex, MUTEX_INIT};
+use std::unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
 
 static mut TASK_COUNT: atomics::AtomicUint = atomics::INIT_ATOMIC_UINT;
-static mut TASK_LOCK: Mutex = MUTEX_INIT;
+static mut TASK_LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
 
 pub fn increment() {
     let _ = unsafe { TASK_COUNT.fetch_add(1, atomics::SeqCst) };

src/libnative/io/net.rs

@@ -218,9 +218,9 @@ pub fn init() {
     }
 
     unsafe {
-        use std::unstable::mutex::{Mutex, MUTEX_INIT};
+        use std::unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
         static mut INITIALIZED: bool = false;
-        static mut LOCK: Mutex = MUTEX_INIT;
+        static mut LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
 
         let _guard = LOCK.lock();
         if !INITIALIZED {

src/libnative/io/timer_helper.rs

@@ -22,7 +22,7 @@
 
 use std::cast;
 use std::rt;
-use std::unstable::mutex::{Mutex, MUTEX_INIT};
+use std::unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
 
 use bookkeeping;
 use io::timer::{Req, Shutdown};
@@ -37,7 +37,7 @@ static mut HELPER_CHAN: *mut Chan<Req> = 0 as *mut Chan<Req>;
 static mut HELPER_SIGNAL: imp::signal = 0 as imp::signal;
 
 pub fn boot(helper: fn(imp::signal, Port<Req>)) {
-    static mut LOCK: Mutex = MUTEX_INIT;
+    static mut LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
     static mut INITIALIZED: bool = false;
 
     unsafe {

src/libnative/task.rs

@@ -22,7 +22,7 @@ use std::rt::task::{Task, BlockedTask, SendMessage};
 use std::rt::thread::Thread;
 use std::rt;
 use std::task::TaskOpts;
-use std::unstable::mutex::Mutex;
+use std::unstable::mutex::StaticNativeMutex;
 use std::unstable::stack;
 
 use io;
@@ -40,7 +40,7 @@ pub fn new(stack_bounds: (uint, uint)) -> ~Task {
 
 fn ops() -> ~Ops {
     ~Ops {
-        lock: unsafe { Mutex::new() },
+        lock: unsafe { StaticNativeMutex::new() },
         awoken: false,
         io: io::IoFactory::new(),
         // these *should* get overwritten
@@ -109,7 +109,7 @@ pub fn spawn_opts(opts: TaskOpts, f: proc()) {
 // This structure is the glue between channels and the 1:1 scheduling mode. This
 // structure is allocated once per task.
 struct Ops {
-    lock: Mutex,       // native synchronization
+    lock: StaticNativeMutex,       // native synchronization
     awoken: bool,      // used to prevent spurious wakeups
     io: io::IoFactory, // local I/O factory
 

src/libstd/comm/shared.rs

@@ -28,7 +28,7 @@ use rt::local::Local;
 use rt::task::{Task, BlockedTask};
 use rt::thread::Thread;
 use sync::atomics;
-use unstable::mutex::Mutex;
+use unstable::mutex::StaticNativeMutex;
 use vec::OwnedVector;
 
 use mpsc = sync::mpsc_queue;
@@ -53,7 +53,7 @@ pub struct Packet<T> {
 
     // this lock protects various portions of this implementation during
     // select()
-    select_lock: Mutex,
+    select_lock: StaticNativeMutex,
 }
 
 pub enum Failure {
@@ -72,7 +72,7 @@ impl<T: Send> Packet<T> {
             channels: atomics::AtomicInt::new(2),
             port_dropped: atomics::AtomicBool::new(false),
             sender_drain: atomics::AtomicInt::new(0),
-            select_lock: unsafe { Mutex::new() },
+            select_lock: unsafe { StaticNativeMutex::new() },
         };
         // see comments in inherit_blocker about why we grab this lock
         unsafe { p.select_lock.lock_noguard() }

src/libstd/os.rs

@@ -144,9 +144,9 @@ Accessing environment variables is not generally threadsafe.
 Serialize access through a global lock.
 */
 fn with_env_lock<T>(f: || -> T) -> T {
-    use unstable::mutex::{Mutex, MUTEX_INIT};
+    use unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
 
-    static mut lock: Mutex = MUTEX_INIT;
+    static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
 
     unsafe {
         let _guard = lock.lock();

src/libstd/rt/args.rs

@@ -68,11 +68,11 @@ mod imp {
     use option::{Option, Some, None};
     use ptr::RawPtr;
     use iter::Iterator;
-    use unstable::mutex::{Mutex, MUTEX_INIT};
+    use unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
     use mem;
 
     static mut global_args_ptr: uint = 0;
-    static mut lock: Mutex = MUTEX_INIT;
+    static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
 
     #[cfg(not(test))]
     pub unsafe fn init(argc: int, argv: **u8) {

src/libstd/unstable/dynamic_lib.rs

@@ -152,8 +152,8 @@ pub mod dl {
     }
 
     pub fn check_for_errors_in<T>(f: || -> T) -> Result<T, ~str> {
-        use unstable::mutex::{Mutex, MUTEX_INIT};
-        static mut lock: Mutex = MUTEX_INIT;
+        use unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
+        static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
         unsafe {
             // dlerror isn't thread safe, so we need to lock around this entire
             // sequence

src/libstd/unstable/mutex.rs

@@ -11,9 +11,9 @@
 //! A native mutex and condition variable type
 //!
 //! This module contains bindings to the platform's native mutex/condition
-//! variable primitives. It provides a single type, `Mutex`, which can be
-//! statically initialized via the `MUTEX_INIT` value. This object serves as both a
-//! mutex and a condition variable simultaneously.
+//! variable primitives. It provides a single type, `StaticNativeMutex`, which can be
+//! statically initialized via the `NATIVE_MUTEX_INIT` value. This object serves as
+//! both a mutex and a condition variable simultaneously.
 //!
 //! The lock is lazily initialized, but it can only be unsafely destroyed. A
 //! statically initialized lock doesn't necessarily have a time at which it can
@@ -27,21 +27,23 @@
 //!
 //! # Example
 //!
-//!     use std::unstable::mutex::{Mutex, MUTEX_INIT};
+//!     use std::unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
 //!
 //!     // Use a statically initialized mutex
-//!     static mut lock: Mutex = MUTEX_INIT;
+//!     static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
 //!
 //!     unsafe {
-//!         lock.lock();
-//!         lock.unlock();
-//!     }
+//!         let _guard = lock.lock();
+//!     } // automatically unlocked here
 //!
 //!     // Use a normally initialized mutex
-//!     let mut lock = Mutex::new();
 //!     unsafe {
-//!         lock.lock();
-//!         lock.unlock();
+//!         let mut lock = StaticNativeMutex::new();
+//!
+//!         // sometimes the RAII guard isn't appropriate
+//!         lock.lock_noguard();
+//!         lock.unlock_noguard();
+//!
 //!         lock.destroy();
 //!     }
 
@@ -50,7 +52,9 @@
 use option::{Option, None, Some};
 use ops::Drop;
 
-pub struct Mutex {
+/// A native mutex suitable for storing in statics (that is, it has
+/// the `destroy` method rather than a destructor).
+pub struct StaticNativeMutex {
     priv inner: imp::Mutex,
 }
 
@@ -62,33 +66,33 @@ pub struct Mutex {
 /// then.
 #[must_use]
 pub struct LockGuard<'a> {
-    priv lock: &'a mut Mutex
+    priv lock: &'a mut StaticNativeMutex
 }
 
-pub static MUTEX_INIT: Mutex = Mutex {
+pub static NATIVE_MUTEX_INIT: StaticNativeMutex = StaticNativeMutex {
     inner: imp::MUTEX_INIT,
 };
 
-impl Mutex {
-    /// Creates a new mutex
-    pub unsafe fn new() -> Mutex {
-        Mutex { inner: imp::Mutex::new() }
+impl StaticNativeMutex {
+    /// Creates a new mutex.
+    ///
+    /// Note that a mutex created in this way needs to be explicit
+    /// freed with a call to `destroy` or it will leak.
+    pub unsafe fn new() -> StaticNativeMutex {
+        StaticNativeMutex { inner: imp::Mutex::new() }
     }
 
     /// Acquires this lock. This assumes that the current thread does not
     /// already hold the lock.
     ///
     /// # Example
-    /// ```
-    /// use std::unstable::mutex::Mutex;
+    /// ```rust
+    /// use std::unstable::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
+    /// static mut LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
     /// unsafe {
-    ///     let mut lock = Mutex::new();
-    ///
-    ///     {
-    ///         let _guard = lock.lock();
-    ///         // critical section...
-    ///     } // automatically unlocked in `_guard`'s destructor
-    /// }
+    ///     let _guard = LOCK.lock();
+    ///     // critical section...
+    /// } // automatically unlocked in `_guard`'s destructor
     /// ```
     pub unsafe fn lock<'a>(&'a mut self) -> LockGuard<'a> {
         self.inner.lock();
@@ -455,20 +459,20 @@ mod test {
     use prelude::*;
 
     use mem::drop;
-    use super::{Mutex, MUTEX_INIT};
+    use super::{StaticNativeMutex, NATIVE_MUTEX_INIT};
     use rt::thread::Thread;
 
     #[test]
     fn smoke_lock() {
-        static mut lock: Mutex = MUTEX_INIT;
+        static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
         unsafe {
             let _guard = lock.lock();
         }
     }
 
     #[test]
     fn smoke_cond() {
-        static mut lock: Mutex = MUTEX_INIT;
+        static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
         unsafe {
             let mut guard = lock.lock();
             let t = Thread::start(proc() {
@@ -484,7 +488,7 @@ mod test {
 
     #[test]
     fn smoke_lock_noguard() {
-        static mut lock: Mutex = MUTEX_INIT;
+        static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
         unsafe {
             lock.lock_noguard();
             lock.unlock_noguard();
@@ -493,7 +497,7 @@ mod test {
 
     #[test]
     fn smoke_cond_noguard() {
-        static mut lock: Mutex = MUTEX_INIT;
+        static mut lock: StaticNativeMutex = NATIVE_MUTEX_INIT;
         unsafe {
             lock.lock_noguard();
             let t = Thread::start(proc() {
@@ -511,7 +515,7 @@ mod test {
     #[test]
     fn destroy_immediately() {
         unsafe {
-            let mut m = Mutex::new();
+            let mut m = StaticNativeMutex::new();
             m.destroy();
         }
     }

src/libstd/unstable/sync.rs

@@ -13,10 +13,10 @@ use kinds::Send;
 use ops::Drop;
 use option::Option;
 use sync::arc::UnsafeArc;
-use unstable::mutex::{Mutex, LockGuard};
+use unstable::mutex::{StaticNativeMutex, LockGuard};
 
 pub struct LittleLock {
-    priv l: Mutex,
+    priv l: StaticNativeMutex,
 }
 
 pub struct LittleGuard<'a> {
@@ -31,7 +31,7 @@ impl Drop for LittleLock {
 
 impl LittleLock {
     pub fn new() -> LittleLock {
-        unsafe { LittleLock { l: Mutex::new() } }
+        unsafe { LittleLock { l: StaticNativeMutex::new() } }
     }
 
     pub unsafe fn lock<'a>(&'a mut self) -> LittleGuard<'a> {