-/* $Id$
-
-This file is part of libmspcore
-Copyright © 2006 Mikko Rasa, Mikkosoft Productions
-Distributed under the LGPL
-*/
#ifndef MSP_CORE_MUTEX_H_
#define MSP_CORE_MUTEX_H_
#include "refptr.h"
-#include "types.h"
namespace Msp {
+/**
+A class for controlling mutually exclusive access to a resource. Only one
+thread can hold a lock on the mutex at a time.
+*/
class Mutex
{
-public:
-#ifndef WIN32
- Mutex() { pthread_mutex_init(&mutex, 0); }
- int lock() { return pthread_mutex_lock(&mutex); }
- int trylock() { return pthread_mutex_trylock(&mutex); }
- int unlock() { return pthread_mutex_unlock(&mutex); }
- ~Mutex() { pthread_mutex_destroy(&mutex); }
-#else
- Mutex() { mutex=CreateMutex(0, false, 0); }
- int lock() { return WaitForSingleObject(mutex, INFINITE)==WAIT_OBJECT_0; }
- int trylock() { return WaitForSingleObject(mutex, 0)==WAIT_OBJECT_0; }
- int unlock() { return !ReleaseMutex(mutex); }
- ~Mutex() { CloseHandle(mutex); }
-#endif
+ friend class Semaphore;
+
private:
- MutexHandle mutex;
+ struct Private;
- friend class Semaphore;
+ Private *priv;
+
+public:
+ Mutex();
+ ~Mutex();
+
+ /** Locks the mutex. If the mutex is already locked, waits until it becomes
+ available. */
+ void lock();
+
+ /** Attempts to lock the mutex. Returns true if the lock was acquired,
+ otherwise returns false. */
+ bool trylock();
+
+ /** Unlocks the mutex. */
+ void unlock();
};
/**
-Locks the mutex for te lifetime of the object.
+Locks the mutex for the lifetime of the object.
*/
class MutexLock
{
-public:
- MutexLock(Mutex &m, bool l=true): mutex(m) { if(l) mutex.lock(); }
- ~MutexLock() { mutex.unlock(); }
-
- int lock() { return mutex.lock(); }
private:
Mutex &mutex;
MutexLock(const MutexLock &);
- MutexLock &operator=(const MutexLock &);
+public:
+ MutexLock(Mutex &m, bool l = true): mutex(m) { if(l) mutex.lock(); }
+ ~MutexLock() { mutex.unlock(); }
+
+ void lock() { mutex.lock(); }
};
/**
template<typename T>
class MutexPtr
{
-public:
- MutexPtr(T *d, Mutex &m): mutex(new MutexLock(m)), data(d) { }
-
- T &operator*() const { return *data; }
- T *operator->() const { return data; }
- void clear() { mutex=0; data=0; }
private:
RefPtr<MutexLock> mutex;
T *data;
-};
-/*template<typename T>
-class MutexPtr: public RefCount
-{
public:
- MutexPtr(T *d, Mutex &m): mutex(m), data(d) { mutex.lock(); }
- MutexPtr(const MutexPtr<T> &p): RefCount(p), mutex(p.mutex), data(p.data) { }
+ MutexPtr(T *d, Mutex &m): mutex(new MutexLock(m)), data(d) { }
+
T &operator*() const { return *data; }
T *operator->() const { return data; }
- void clear() { decref(); data=0; }
- ~MutexPtr() { decref(); }
-protected:
- Mutex &mutex;
- T *data;
-
- bool decref()
- {
- if(!RefCount::decref())
- {
- mutex.unlock();
- return false;
- }
- return true;
- }
-};*/
+ void clear() { mutex = 0; data = 0; }
+};
}