rts/include/umlrtmutex.hh

// umlrtmutex.hh

/*******************************************************************************
* Copyright (c) 2014-2015 Zeligsoft (2009) Limited  and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*******************************************************************************/

#ifndef UMLRTMUTEX_HH
#define UMLRTMUTEX_HH

#include <pthread.h>
#include <stdint.h>

// UMLRTMutex is platform-independent mutual-exclusion.

// Currently not os-indepedent.
// Bug 32 tracks move of this implementation to +/os/linux.

class UMLRTMutexGuard
{
public:
    UMLRTMutexGuard ( pthread_mutex_t & m_ ) : mutex(m_) { pthread_mutex_lock( &mutex ); }
    ~ UMLRTMutexGuard ( ) { pthread_mutex_unlock( &mutex ); }
private:
    pthread_mutex_t mutex;
};

class UMLRTMutex
{
public:
    UMLRTMutex();

    // Can create a mutex which starts life as taken already.
    UMLRTMutex( bool taken );

    ~UMLRTMutex();

    // Wait forever for it to be available.
    void take(void);

    // Wait only so many milliseconds.
    // Timed - returns true for success, false for timeout.
    bool take( uint32_t msec );

    // Give it back.
    void give(void);

private:
    pthread_mutex_t guard;
    pthread_cond_t condition;
    bool locked;
};

#endif // UMLRTMUTEX_HH