Subversion Repositories openrisc_2011-10-31

#ifndef CYGONCE_KERNEL_MUTEX_HXX

#define CYGONCE_KERNEL_MUTEX_HXX

//==========================================================================

//

//      mutex.hxx

//

//      Mutex class declarations

//

//==========================================================================

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// -------------------------------------------

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//

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// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

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// or inline functions from this file, or you compile this file and link it

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// -------------------------------------------

//####ECOSGPLCOPYRIGHTEND####

//==========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):   nickg

// Contributors:        nickg

// Date:        1997-09-09

// Purpose:     Define Mutex class interfaces

// Description: The classes defined here provide the APIs for mutexes

//              and condition variables.

// Usage:       #include 

//

//

//####DESCRIPTIONEND####

//

//==========================================================================

#include 

#include          // assertion macros

#include 

// -------------------------------------------------------------------------

// Mutex.

class Cyg_Mutex

{

    friend class Cyg_Condition_Variable;

    cyg_atomic          locked;         // true if locked. This may seem

                                        // redundant due to "owner" below,

                                        // but is intentionally present for

                                        // future SMP support.

    Cyg_Thread          *owner;         // Current locking thread

    Cyg_ThreadQueue     queue;          // Queue of waiting threads

#ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_DYNAMIC

public:

    enum cyg_protcol

    {

        NONE = 0,                       // no inversion protocol

        INHERIT,                        // priority inheritance protocol

        CEILING                         // priority ceiling protocol

    };

private:

    cyg_protcol protocol;               // this mutex's protocol

#endif

#ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_CEILING

private:

    cyg_priority        ceiling;        // mutex priority ceiling

#endif

public:

    CYGDBG_DEFINE_CHECK_THIS

    Cyg_Mutex();                        // Create in unlocked state

#ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_DYNAMIC

    Cyg_Mutex( cyg_protcol protocol );  // Create with defined protocol

#endif

    ~Cyg_Mutex();                       // Destructor

    cyg_bool    lock();                 // lock and/or wait

    cyg_bool    trylock();              // try to lock and return success

    void        unlock();               // unlock

    void        release();              // release all waiting threads

    // Get the current owning thread

    inline Cyg_Thread *get_owner() { return owner; }

#ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_CEILING

    // set ceiling priority for priority ceiling protocol

    void        set_ceiling( cyg_priority priority );

    cyg_priority get_ceiling(void) { return ceiling; };

#endif

#ifdef CYGSEM_KERNEL_SYNCH_MUTEX_PRIORITY_INVERSION_PROTOCOL_DYNAMIC

    // set inversion protocol

    void        set_protocol( cyg_protcol new_protocol );

#endif

};

// -------------------------------------------------------------------------

// Condition variable.

class Cyg_Condition_Variable

{

    Cyg_Mutex           *mutex;         // Associated mutex

    Cyg_ThreadQueue     queue;          // Queue of waiting threads

    // Private internal implementation function for wait operations

    cyg_bool wait_inner( Cyg_Mutex *mutex );

#ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_TIMED_WAIT

    // Private internal implementation function for timed wait operations

    cyg_bool wait_inner( Cyg_Mutex *mutex, cyg_tick_count timeout );

#endif

public:

    CYGDBG_DEFINE_CHECK_THIS

    Cyg_Condition_Variable();           // simple constructor

    Cyg_Condition_Variable(

        Cyg_Mutex &mutex                // linked mutex

        );

    ~Cyg_Condition_Variable();          // Destructor

    void     signal();                  // Set cond true, wake one thread

    void     broadcast();               // Set cond true, wake all threads

    // Wait for condition to be true

    inline cyg_bool wait() { return wait_inner( mutex ); }

#ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_TIMED_WAIT

    // Wait until a signal or timeout expiry

    inline cyg_bool wait( cyg_tick_count timeout )

    { return wait_inner( mutex, timeout ); }

#endif

#ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_WAIT_MUTEX

    // Wait for condition to be true using the supplied mutex

    inline cyg_bool wait( Cyg_Mutex &mx ) { return wait_inner( &mx ); }

#ifdef CYGMFN_KERNEL_SYNCH_CONDVAR_TIMED_WAIT

    // Wait until a signal or timeout expiry, using the supplied mutex

    inline cyg_bool wait( Cyg_Mutex &mx, cyg_tick_count timeout )

    { return wait_inner( &mx, timeout ); }

#endif

#endif

    // Return a pointer to this variables thread queue. Used mainly

    // for testing whether a thread is on the queue for a particular

    // cv.

    inline Cyg_ThreadQueue *get_queue() { return &queue; };

};

// -------------------------------------------------------------------------

#endif // ifndef CYGONCE_KERNEL_MUTEX_HXX

// EOF mutex.hxx