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#ifndef CYGONCE_KERNEL_SEMA_HXX

#define CYGONCE_KERNEL_SEMA_HXX

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

//

//      sema.hxx

//

//      Semaphore class declarations

//

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

//####ECOSGPLCOPYRIGHTBEGIN####

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

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.

//

// eCos is free software; you can redistribute it and/or modify it under

// the terms of the GNU General Public License as published by the Free

// Software Foundation; either version 2 or (at your option) any later version.

//

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// WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

// for more details.

//

// You should have received a copy of the GNU General Public License along

// with eCos; if not, write to the Free Software Foundation, Inc.,

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

//

// As a special exception, if other files instantiate templates or use macros

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

// with other works to produce a work based on this file, this file does not

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// at http://sources.redhat.com/ecos/ecos-license/

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

//####ECOSGPLCOPYRIGHTEND####

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

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

//

// Author(s):   nickg

// Contributors:        nickg

// Date:        1997-09-09

// Purpose:     Define Semaphore class interfaces

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

//              and counting semaphores.

// Usage:       #include 

//

//

//####DESCRIPTIONEND####

//

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

#include 

#include          // assertion macros

#include        // thread inlines

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

// Binary semaphore. This has only two states: posted and not-posted.

class Cyg_Binary_Semaphore

{

    cyg_bool            state;          // The binary semaphore state

    Cyg_ThreadQueue     queue;          // Queue of waiting threads

public:

    CYGDBG_DEFINE_CHECK_THIS

    Cyg_Binary_Semaphore(               // Constructor

        cyg_bool init_state = false     // Initial state value

        );

    ~Cyg_Binary_Semaphore();            // Destructor

    cyg_bool    wait();                 // Wait until state == true

    cyg_bool    trywait();              // Set state false if possible

    void        post();                 // Increment count

    cyg_bool    posted();               // Get current state

};

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

// Counting semaphore. This implements the usual counter based semaphore.

class Cyg_Counting_Semaphore

{

    cyg_count32         count;          // The semaphore count

    Cyg_ThreadQueue     queue;          // Queue of waiting threads

public:

    CYGDBG_DEFINE_CHECK_THIS

    Cyg_Counting_Semaphore(             // Constructor

        cyg_count32 init_count = 0      // Initial count value

        );

    ~Cyg_Counting_Semaphore();          // Destructor

    cyg_bool    wait();                 // Wait until decrement

#ifdef CYGFUN_KERNEL_THREADS_TIMER

    cyg_bool    wait( cyg_tick_count timeout );

#endif                                  // Wait until decrement or timeout

    cyg_bool    trywait();              // Try to decrement

    void        post();                 // Increment count

    cyg_count32 peek() const;           // Get current count value

    inline

    cyg_bool    waiting()               // Is anyone waiting?

    {

        return !queue.empty();

    }

};

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

#endif // ifndef CYGONCE_KERNEL_SEMA_HXX

// EOF sema.hxx