comparison thread/Thread.h @ 62:b63f1ccbc9b6

* oops... add thread abstraction

+/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */
+
+/*
+    QM DSP Library
+
+    Centre for Digital Music, Queen Mary, University of London.
+    This file copyright Chris Cannam, used with permission.
+*/
+
+#ifndef _THREAD_H_
+#define _THREAD_H_
+
+#ifdef _WIN32
+#include <windows.h>
+#else /* !_WIN32 */
+#ifdef USE_PTHREADS
+#include <pthread.h>
+#endif /* USE_PTHREADS */
+#endif /* !_WIN32 */
+
+#include <string>
+
+//#define DEBUG_THREAD 1
+//#define DEBUG_MUTEX 1
+//#define DEBUG_CONDITION 1
+
+class Thread
+{
+public:
+#ifdef _WIN32
+    typedef HANDLE Id;
+#else
+#ifdef USE_PTHREADS
+    typedef pthread_t Id;
+#endif
+#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
+#ifdef USE_PTHREADS
+    pthread_t m_id;
+    bool m_extant;
+    static void *staticRun(void *);
+#endif
+#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
+#ifdef USE_PTHREADS
+    pthread_mutex_t m_mutex;
+#ifndef NO_THREAD_CHECKS
+    pthread_t m_lockedBy;
+    bool m_locked;
+#endif
+#endif
+#endif
+};
+
+class MutexLocker
+{
+public:
+    MutexLocker(Mutex *);
+    ~MutexLocker();
+
+private:
+    Mutex *m_mutex;
+};
+
+class Condition
+{
+public:
+    Condition(std::string name);
+    ~Condition();
+
+    //!!! NO -- reproducing more conventional lock/wait
+    
+    // To wait on a condition, either simply call wait(), or call
+    // lock() and then wait() (perhaps testing some state in between).
+    // To signal a condition, call signal().
+
+    // Although any thread may signal on a given condition, only one
+    // thread should ever wait on any given condition object --
+    // otherwise there will be a race conditions in the logic that
+    // avoids the thread code having to track whether the condition's
+    // mutex is locked or not.  If that is your requirement, this
+    // Condition wrapper is not for you.
+    void lock();
+    void unlock();
+    void wait(int us = 0);
+
+    void signal();
+    
+private:
+
+#ifdef _WIN32
+    HANDLE m_mutex;
+    HANDLE m_condition;
+    bool m_locked;
+#else
+#ifdef USE_PTHREADS
+    pthread_mutex_t m_mutex;
+    pthread_cond_t m_condition;
+    bool m_locked;
+#endif
+#endif
+#ifdef DEBUG_CONDITION
+    std::string m_name;
+#endif
+};
+
+#endif