xref: /external/webrtc/src/system_wrappers/source/condition_variable_win.h

/*
 *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef WEBRTC_SYSTEM_WRAPPERS_SOURCE_CONDITION_VARIABLE_WINDOWS_H_
#define WEBRTC_SYSTEM_WRAPPERS_SOURCE_CONDITION_VARIABLE_WINDOWS_H_

#include "condition_variable_wrapper.h"

#include <windows.h>

namespace webrtc {
#if !defined CONDITION_VARIABLE_INIT
    typedef struct _RTL_CONDITION_VARIABLE
    {
        void* Ptr;
    } RTL_CONDITION_VARIABLE, *PRTL_CONDITION_VARIABLE;

    typedef RTL_CONDITION_VARIABLE CONDITION_VARIABLE, *PCONDITION_VARIABLE;
#endif

typedef void (WINAPI *PInitializeConditionVariable)(PCONDITION_VARIABLE);
typedef BOOL (WINAPI *PSleepConditionVariableCS)(PCONDITION_VARIABLE,
                                                 PCRITICAL_SECTION, DWORD);
typedef void (WINAPI *PWakeConditionVariable)(PCONDITION_VARIABLE);
typedef void (WINAPI *PWakeAllConditionVariable)(PCONDITION_VARIABLE);


class ConditionVariableWindows : public ConditionVariableWrapper
{
public:
    ConditionVariableWindows();
    ~ConditionVariableWindows();

    void SleepCS(CriticalSectionWrapper& critSect);
    bool SleepCS(CriticalSectionWrapper& critSect, unsigned long maxTimeInMS);
    void Wake();
    void WakeAll();

private:
    enum EventWakeUpType
    {
        WAKEALL_0   = 0,
        WAKEALL_1   = 1,
        WAKE        = 2,
        EVENT_COUNT = 3
    };

private:
    // Native support for Windows Vista+
    static bool              _winSupportConditionVariablesPrimitive;
    CONDITION_VARIABLE       _conditionVariable;

    unsigned int     _numWaiters[2];
    EventWakeUpType  _eventID;
    CRITICAL_SECTION _numWaitersCritSect;
    HANDLE           _events[EVENT_COUNT];
};
} // namespace webrtc

#endif // WEBRTC_SYSTEM_WRAPPERS_SOURCE_CONDITION_VARIABLE_WINDOWS_H_