Subversion Repositories openrisc_2011-10-31

#ifndef CYGONCE_KERNEL_MBOXT_HXX

#define CYGONCE_KERNEL_MBOXT_HXX

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

//

//      mboxt.hxx

//

//      Mboxt (Message Box/Mailbox) 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.

//

// eCos is distributed in the hope that it will be useful, but WITHOUT ANY

// 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

// by itself cause the resulting work to be covered by the GNU General Public

// License. However the source code for this file must still be made available

// in accordance with section (3) of the GNU General Public License.

//

// This exception does not invalidate any other reasons why a work based on

// this file might be covered by the GNU General Public License.

//

// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.

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

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

//####ECOSGPLCOPYRIGHTEND####

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

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

//

// Author(s):   hmt

// Contributors:        hmt

// Date:        1998-02-10

// Purpose:     Define Mboxt class interfaces

// Description: The classes defined here provide the APIs for mboxtes.

// Usage:       #include 

//              #include 

//

//

//####DESCRIPTIONEND####

//

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

#include 

#include             // assertion macros

#include 

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

// Message/Mail Box.  This template implements a queue of T's.

// Implemented as a template for maximal flexibility; one would hope

// that only one, with T==(void *) and the same number of them,

// is ever used without very good reason.

// Cyg_Mboxt has a fixed size array of T's; one size fits all.

template 

class Cyg_Mboxt

{

private:

    cyg_count32         base;           // index of first used slot

    cyg_count32         count;          // count of used slots

    Cyg_ThreadQueue     get_threadq;    // Queue of waiting threads

#ifdef CYGMFN_KERNEL_SYNCH_MBOXT_PUT_CAN_WAIT

    Cyg_ThreadQueue     put_threadq;    // Queue of waiting threads

#endif

    static const

    cyg_count32         size = QUEUE_SIZE;

    T                   itemqueue[ QUEUE_SIZE ];

                                        // queue of items

    // private utility functions

    // wake up a thread from some queue

    inline void         wakeup_waiter( Cyg_ThreadQueue &q );

public:

    CYGDBG_DEFINE_CHECK_THIS

    Cyg_Mboxt();                        // Constructor

    ~Cyg_Mboxt();                       // Destructor

    cyg_bool    get( T &ritem );        // get an item; wait if none

#ifdef CYGFUN_KERNEL_THREADS_TIMER

    cyg_bool    get( T &ritem, cyg_tick_count abs_timeout );

#endif

    cyg_bool    tryget( T &ritem );     // just one attempt

    cyg_bool    peek_item( T &ritem );  // get next item without

                                        // removing it

#ifdef CYGMFN_KERNEL_SYNCH_MBOXT_PUT_CAN_WAIT

    cyg_bool    put( const T item );    // put an item; wait if full

#ifdef CYGFUN_KERNEL_THREADS_TIMER

    cyg_bool    put( const T item, cyg_tick_count abs_timeout );

#endif

#endif

    cyg_bool    tryput( const T item ); // fails if Q full

    inline

    cyg_count32 peek()                  // Get current count value

    {

        return count;

    }

    inline

    cyg_bool    waiting_to_get()        // Any threads waiting?

    {

        return ! get_threadq.empty();

    }

    inline

    cyg_bool    waiting_to_put()        // Any threads waiting?

    {

#ifdef CYGMFN_KERNEL_SYNCH_MBOXT_PUT_CAN_WAIT

        return ! put_threadq.empty();

#else

        return false;

#endif

    }

};

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

#endif // ifndef CYGONCE_KERNEL_MBOXT_HXX

// EOF mboxt.hxx