ringbuf.h

来自「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」· C头文件 代码 · 共 72 行

#ifndef	__RINGBUF_H
#define	__RINGBUF_H

#include "config.h"

/*
**	ring buffer control
**
**	..uuudddddd...
**	  B   R   W
**
*/

#if 0
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;}
#endif

#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;
}
#else
#define	WRAPl(r, s)		(((r) <   0 ) ? ((r) + (s)) : (r))
#define	WRAPr(r, s)		(((r) >= (s)) ? ((r) - (s)) : (r))
#endif

static inline int RingBufferSize_CD(int Wp, int Rp, int L)
{
    int			S = Wp - Rp;

    if (S < 0)
	S += L;
    S = (S * 288) / 1024;	// because CD_MOVE width is 288 and original is 1024
    return S;
}

static inline int RingBufferFree_CD(int Wp, int Bp, int L)
{
    int			F = Bp - Wp;

    if (F <= 0)
	F += L;
    F = (F * 288) / 1024;	// because CD_MOVE width is 288 and original is 1024
    return F;
}

static inline int RingBufferSize(int Wp, int Rp, int L)
{
    int			S = Wp - Rp;

    if (S < 0)
	S += L;
    return S;
}

static inline int RingBufferFree(int Wp, int Bp, int L)
{
    int			F = Bp - Wp;

    if (F <= 0)
	F += L;
    return F;
}

#endif	__RINGBUF_H