//////////////////////////////////////////////////////////////////////////////////
// File     : mwmr_channel.h         
// Date     : 01/04/2012
// Author   : alain greiner
// Copyright (c) UPMC-LIP6
///////////////////////////////////////////////////////////////////////////////////

#ifndef _MWMR_CHANNEL_H_
#define _MWMR_CHANNEL_H_

///////////////////////////////////////////////////////////////////////////////////
//  MWMR channel structure
// The data array size is defined to obtain sizeof(mwmr_channel_t) = 4096 bytes.
// The actual size can be redefined in the mapping info data structure.
///////////////////////////////////////////////////////////////////////////////////

typedef struct mwmr_channel_s 
{
    unsigned int ptr;        // index of the first valid data word
    unsigned int ptw;        // index of the first empty slot 
    unsigned int sts;        // number of words available
    unsigned int lock;       // exclusive access lock
    unsigned int depth;      // max number of words in the channel
    unsigned int width;      // number of words in an item      
    unsigned int data[1018]; // circular buffer
} mwmr_channel_t;

//////////////////////////////////////////////////////////////////////////////
//  MWMR access functions
//////////////////////////////////////////////////////////////////////////////

void mwmr_write( mwmr_channel_t* mwmr, 
                 unsigned int*   buffer, 
                 unsigned int    nitems );

void mwmr_read(  mwmr_channel_t* mwmr, 
                 unsigned int*   buffer, 
                 unsigned int    nitems );

unsigned int nb_mwmr_read ( mwmr_channel_t * mwmr,
                            unsigned int * buffer,
                            unsigned int nitems );


unsigned int nb_mwmr_write( mwmr_channel_t * mwmr,
                            unsigned int * buffer,
                            unsigned int nitems );

#endif

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