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#include "fifo.h"

u8 fifo_init (fifo_t *f, u8 *buffer, const u16 size)

{

        if(f == NULL) return(0);

        f->buffer = buffer;

        f->size = size;

        fifo_purge(f);

        return(1);

}

u8 fifo_put (fifo_t *f, const u8 data)

{

        if (f->count >= f->size) return(0);     // return 0 in case of FIFO overflow.

        u8 * pwrite = f->pwrite;

        *(pwrite++) = data;         // copy data byte to buffer

        if(pwrite >= f->buffer + f->size) pwrite = f->buffer; // start at the begining after reaching the end 

        f->pwrite = pwrite;

        f->count++;

        return 1;

}

u8 fifo_get (fifo_t *f, u8 *pdata)

{

        if((f == NULL) || (pdata == NULL)) return(0);

        if(!f->count) return(0);

        u8 *pread = f->pread;

        *pdata = *(pread++);

        if(pread >= f->buffer + f->size) pread = f->buffer; // start at the begining after reaching the end 

        f->pread = pread;

        f->count--;

        return(1);

}

u8 fifo_get_wait (fifo_t *f, u8 *pdata)

{

        while (!f->count);

        return fifo_get(f, pdata);

}

void fifo_purge(fifo_t* f)

{

        if((f == NULL)) return;

        f->count = 0;

        f->pread = f->buffer;

        f->pwrite = f->buffer;

        return;

}