fifo.h

C语言编写的监控中心终端程序。基于GPRS上传收发数据功能

#ifndef __FIFO_H__
#define __FIFO_H__

#include "regmap.h"
#include "getbits.h"
#include "types.h"

typedef struct
{
    unsigned char	*data;
    int			size;
    int			head;
    int			tail;

    unsigned		word;
    int			bit_left;
}   tFifo;

#ifdef ENABLE_INLINE
static inline int WRAPl(int r, int s)
{
    return (r < 0) ? (r + s) : r;
}
static inline int WRAPr(int r, int s)
{
    return (r >= s) ? (r - s) : r;
}
static inline void FifoTailAdv(tFifo * fifo, int n)
{
    fifo->tail = WRAPr(fifo->tail + n, fifo->size);
}
static inline void FifoHeadAdv(tFifo * fifo, int n)
{
    fifo->head = WRAPr(fifo->head + n, fifo->size);
}
#else
#define	WRAPl(r, s)		(((r) <   0 ) ? ((r) + (s)) : (r))
#define	WRAPr(r, s)		(((r) >= (s)) ? ((r) - (s)) : (r))
#define	FifoTailAdv(f, n)	(f->tail = WRAPr(f->tail + n, f->size))
#endif

/*
static inline unsigned FifoGetByte(tFifo *fifo)
{
    int			size = fifo->size;
    int			tail = fifo->tail;
    unsigned		c = fifo->data[tail];

    fifo->tail = WRAPr(tail + 1, size);
    return c;
}
*/

#ifdef ENABLE_INLINE
static inline unsigned FifoRetrieve(tFifo * fifo, int i)
{
    int			size = fifo->size;
    int			tail = fifo->tail;

    return fifo->data[WRAPr(tail + i, size)];
}
#endif

#define	FifoGetLength(fifo)	(WRAPl((fifo)->head-(fifo)->tail, (fifo)->size))
#define	FifoGetFree(fifo)	((fifo)->size - FifoGetLength(fifo))
#define	FifoGetBitInit(fifo)	((fifo)->bit_left = 0)
#define	FifoGetBitRestart(fifo)	(FifoGetBitInit(fifo))

unsigned		FifoGetByte(tFifo *);
unsigned		FifoGetWord(tFifo *);
unsigned		FifoGetBits(tFifo *, int);

#ifdef __GNUC__
static inline void FifoLoad(tFifo * f, char *p, int len)
{
    int			l1;
    int			head = f->head;
    int			size = f->size;

    if ((l1 = size - head) < len) {
	memcpy(f->data + head, p, l1);
	len -= l1;
	p += l1;
	head = 0;
    }
    memcpy(f->data + head, p, len);
    f->head = head + len;
}
#endif

int			FifoDMARead(tFifo *, int, int);

#endif	__FIFO_H__