Home | History | Annotate | Download | only in wtf 
      1 /*
      2  * Copyright (C) 2007, 2008, 2010 Apple Inc. All rights reserved.
      3  * Copyright (C) 2007 Justin Haygood (jhaygood (at) reaktix.com)
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  *
      9  * 1.  Redistributions of source code must retain the above copyright
     10  *     notice, this list of conditions and the following disclaimer.
     11  * 2.  Redistributions in binary form must reproduce the above copyright
     12  *     notice, this list of conditions and the following disclaimer in the
     13  *     documentation and/or other materials provided with the distribution.
     14  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
     15  *     its contributors may be used to endorse or promote products derived
     16  *     from this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
     19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     21  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
     22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
     25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     28  *
     29  */
     30 
     31 #ifndef ThreadingPrimitives_h
     32 #define ThreadingPrimitives_h
     33 
     34 #include "wtf/Platform.h"
     35 
     36 #include "wtf/Assertions.h"
     37 #include "wtf/FastAllocBase.h"
     38 #include "wtf/Locker.h"
     39 #include "wtf/Noncopyable.h"
     40 #include "wtf/WTFExport.h"
     41 
     42 #if OS(WINDOWS)
     43 #include <windows.h>
     44 #endif
     45 
     46 #if USE(PTHREADS)
     47 #include <pthread.h>
     48 #endif
     49 
     50 namespace WTF {
     51 
     52 #if USE(PTHREADS)
     53 typedef pthread_mutex_t PlatformMutex;
     54 typedef pthread_cond_t PlatformCondition;
     55 #elif OS(WINDOWS)
     56 struct PlatformMutex {
     57     CRITICAL_SECTION m_internalMutex;
     58     size_t m_recursionCount;
     59 };
     60 struct PlatformCondition {
     61     size_t m_waitersGone;
     62     size_t m_waitersBlocked;
     63     size_t m_waitersToUnblock;
     64     HANDLE m_blockLock;
     65     HANDLE m_blockQueue;
     66     HANDLE m_unblockLock;
     67 
     68     bool timedWait(PlatformMutex&, DWORD durationMilliseconds);
     69     void signal(bool unblockAll);
     70 };
     71 #else
     72 typedef void* PlatformMutex;
     73 typedef void* PlatformCondition;
     74 #endif
     75 
     76 class WTF_EXPORT Mutex {
     77     WTF_MAKE_NONCOPYABLE(Mutex); WTF_MAKE_FAST_ALLOCATED;
     78 public:
     79     Mutex();
     80     ~Mutex();
     81 
     82     void lock();
     83     bool tryLock();
     84     void unlock();
     85 
     86 public:
     87     PlatformMutex& impl() { return m_mutex; }
     88 private:
     89     PlatformMutex m_mutex;
     90 };
     91 
     92 typedef Locker<Mutex> MutexLocker;
     93 
     94 class MutexTryLocker {
     95     WTF_MAKE_NONCOPYABLE(MutexTryLocker);
     96 public:
     97     MutexTryLocker(Mutex& mutex) : m_mutex(mutex), m_locked(mutex.tryLock()) { }
     98     ~MutexTryLocker()
     99     {
    100         if (m_locked)
    101             m_mutex.unlock();
    102     }
    103 
    104     bool locked() const { return m_locked; }
    105 
    106 private:
    107     Mutex& m_mutex;
    108     bool m_locked;
    109 };
    110 
    111 class WTF_EXPORT ThreadCondition {
    112     WTF_MAKE_NONCOPYABLE(ThreadCondition);
    113 public:
    114     ThreadCondition();
    115     ~ThreadCondition();
    116 
    117     void wait(Mutex&);
    118     // Returns true if the condition was signaled before absoluteTime, false if the absoluteTime was reached or is in the past.
    119     // The absoluteTime is in seconds, starting on January 1, 1970. The time is assumed to use the same time zone as WTF::currentTime().
    120     bool timedWait(Mutex&, double absoluteTime);
    121     void signal();
    122     void broadcast();
    123 
    124 private:
    125     PlatformCondition m_condition;
    126 };
    127 
    128 #if OS(WINDOWS)
    129 // The absoluteTime is in seconds, starting on January 1, 1970. The time is assumed to use the same time zone as WTF::currentTime().
    130 // Returns an interval in milliseconds suitable for passing to one of the Win32 wait functions (e.g., ::WaitForSingleObject).
    131 DWORD absoluteTimeToWaitTimeoutInterval(double absoluteTime);
    132 #endif
    133 
    134 } // namespace WTF
    135 
    136 using WTF::Mutex;
    137 using WTF::MutexLocker;
    138 using WTF::MutexTryLocker;
    139 using WTF::ThreadCondition;
    140 
    141 #if OS(WINDOWS)
    142 using WTF::absoluteTimeToWaitTimeoutInterval;
    143 #endif
    144 
    145 #endif // ThreadingPrimitives_h
    146