librubberband/src/system/Thread.h

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Rubber Band
    An audio time-stretching and pitch-shifting library.
    Copyright 2007-2009 Chris Cannam.
    
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _RUBBERBAND_THREAD_H_
#define _RUBBERBAND_THREAD_H_

#ifdef _WIN32
#include <windows.h>
#else /* !_WIN32 */
#include <pthread.h>
#endif /* !_WIN32 */

#include <string>

//#define DEBUG_THREAD 1
//#define DEBUG_MUTEX 1
//#define DEBUG_CONDITION 1

namespace RubberBand
{

class Thread
{
public:
#ifdef _WIN32
    typedef HANDLE Id;
#else
    typedef pthread_t Id;
#endif

    Thread();
    virtual ~Thread();

    Id id();

    void start();
    void wait();

    static bool threadingAvailable();

protected:
    virtual void run() = 0;

private:
#ifdef _WIN32
    HANDLE m_id;
    bool m_extant;
    static DWORD WINAPI staticRun(LPVOID lpParam);
#else
    pthread_t m_id;
    bool m_extant;
    static void *staticRun(void *);
#endif
};

class Mutex
{
public:
    Mutex();
    ~Mutex();

    void lock();
    void unlock();
    bool trylock();

private:
#ifdef _WIN32
    HANDLE m_mutex;
#ifndef NO_THREAD_CHECKS
    DWORD m_lockedBy;
#endif
#else
    pthread_mutex_t m_mutex;
#ifndef NO_THREAD_CHECKS
    pthread_t m_lockedBy;
    bool m_locked;
#endif
#endif
};

class MutexLocker
{
public:
    MutexLocker(Mutex *);
    ~MutexLocker();

private:
    Mutex *m_mutex;
};

class Condition
{
public:
    Condition(std::string name);
    ~Condition();
    
    // The Condition class bundles a condition variable and mutex.

    // To wait on a condition, call lock(), test the termination
    // condition if desired, then wait().  The condition will be
    // unlocked during the wait and re-locked when wait() returns
    // (which will happen when the condition is signalled or the timer
    // times out).

    // To signal a condition, call signal().  If the condition is
    // signalled between lock() and wait(), the signal may be missed
    // by the waiting thread.  To avoid this, the signalling thread
    // should also lock the condition before calling signal() and
    // unlock it afterwards.

    void lock();
    void unlock();
    void wait(int us = 0);

    void signal();
    
private:

#ifdef _WIN32
    HANDLE m_mutex;
    HANDLE m_condition;
    bool m_locked;
#else
    pthread_mutex_t m_mutex;
    pthread_cond_t m_condition;
    bool m_locked;
#endif
#ifdef DEBUG_CONDITION
    std::string m_name;
#endif
};

}

#endif