ibrcommon/ibrcommon/thread/Mutex.cpp

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#include "ibrcommon/config.h"
#include "ibrcommon/thread/Mutex.h"
#include <errno.h>

namespace ibrcommon
{
        Mutex::Mutex(MUTEX_TYPE type)
        {
                pthread_mutexattr_t attr;
                pthread_mutexattr_init(&attr);
                pthread_mutexattr_settype(&attr, type);
                pthread_mutex_init(&m_mutex, &attr);
                pthread_mutexattr_destroy(&attr);
        }

        Mutex::~Mutex()
        {
                pthread_mutex_destroy( &m_mutex );
        }

        void Mutex::trylock() throw (MutexException)
        {
                int ret = pthread_mutex_trylock( &m_mutex );

                switch (ret)
                {
                case 0:
                        break;

                case EBUSY:
                        throw MutexException("The mutex could not be acquired because it was already locked.");
                        break;
                }
        }

        void Mutex::enter() throw (MutexException)
        {
                switch (pthread_mutex_lock( &m_mutex ))
                {
                case 0:
                        return;

//              case EINVAL:
//                      throw MutexException("The mutex was created with the protocol attribute having the value PTHREAD_PRIO_PROTECT and the calling thread's priority is higher than the mutex's current priority ceiling.");

                // The pthread_mutex_trylock() function will fail if:

                case EBUSY:
                        throw MutexException("The mutex could not be acquired because it was already locked.");

                // The pthread_mutex_lock(), pthread_mutex_trylock() and pthread_mutex_unlock() functions may fail if:

                case EINVAL:
                        throw MutexException("The value specified by mutex does not refer to an initialised mutex object.");

                case EAGAIN:
                        throw MutexException("The mutex could not be acquired because the maximum number of recursive locks for mutex has been exceeded.");

                // The pthread_mutex_lock() function may fail if:

                case EDEADLK:
                        throw MutexException("The current thread already owns the mutex.");

                // The pthread_mutex_unlock() function may fail if:

                case EPERM:
                        throw MutexException("The current thread does not own the mutex.");

                default:
                        throw MutexException("can not lock the mutex");
                }
        }

        void Mutex::leave() throw (MutexException)
        {
                if (0 != pthread_mutex_unlock( &m_mutex ))
                {
                        throw MutexException("can not unlock mutex");
                }
        }
}