roundbuf.c

来自「在ARM7和UC/OSII的平台上实现了GPS自动报站的功能,涉及GPS模块LE」· C语言 代码 · 共 152 行

/****************************************************************
**                                                              *
**  FILE         :  RoundBuf.C                                  *
**  COPYRIGHT    :  (c) 2004 .Xiamen Yaxon NetWork CO.LTD       *
**                                                              *
**                                                              *
****************************************************************/
#include "includes.h"
#include "roundbuf.h"
#include "zprint.h"
#include "errtask.h"
void InitRoundBuf(ROUNDBUF_STRUCT *round, INT8U *mem, INT32U memsize, ASMRULE_STRUCT *rule)
{
    round->bufsize = memsize;
    round->used    = 0;
    round->bptr    = mem;
    round->eptr    = mem + memsize;
    round->wptr = round->rptr = round->bptr;
    round->rule = rule;
}

void ResetRoundBuf(ROUNDBUF_STRUCT *round)
{
    round->used = 0;
    round->rptr = round->wptr = round->bptr;
}

INT8U *RoundBufStartPos(ROUNDBUF_STRUCT *round)
{
    return round->bptr;
}

BOOLEAN WriteRoundBuf(ROUNDBUF_STRUCT *round, INT8U data)
{
    if(NULL == round) ErrExit(0x5788);
    if (round->used >= round->bufsize) return FALSE;
    *round->wptr++ = data;
    if (round->wptr >= round->eptr) round->wptr = round->bptr;

    OS_ENTER_CRITICAL();
    round->used++;
    OS_EXIT_CRITICAL();
    return TRUE;
}

INT32S ReadRoundBuf(ROUNDBUF_STRUCT *round)
{
    INT32S ret;
    
    if (round->used == 0) return -1;
    ret = *round->rptr++;
    if (round->rptr >= round->eptr) round->rptr = round->bptr;

    OS_ENTER_CRITICAL();
    round->used--;
    OS_EXIT_CRITICAL();
    return ret;
}

INT32S ReadRoundBufNoMVPtr(ROUNDBUF_STRUCT *round)
{
    if (round->used == 0) return -1;
    else return *round->rptr; 
}

INT32U LeftOfRoundBuf(ROUNDBUF_STRUCT *round)
{
    return (round->bufsize - round->used);
}

INT32U UsedOfRoundBuf(ROUNDBUF_STRUCT *round)
{
       return round->used;
}
INT32U UsedOfRoundBuf2(ROUNDBUF_STRUCT *round)
{
       return round->used;
}

BOOLEAN WriteBlockRoundBuf(ROUNDBUF_STRUCT *round, INT8U *bptr, INT32U blksize)
{
    if (blksize > LeftOfRoundBuf(round)) return FALSE;
    for (; blksize > 0; blksize--) { 
       *round->wptr++ = *bptr++;
       if (round->wptr >= round->eptr) round->wptr = round->bptr;
       OS_ENTER_CRITICAL();
       round->used++;
       OS_EXIT_CRITICAL();
    }    
    return TRUE;
}

INT32U DeassembleRoundBuf(ROUNDBUF_STRUCT *round, INT8U *dptr, INT32U maxlen)
{
    INT8U  *rptr;
    INT8U  cur, pre;
    INT32U used, ct;
    INT32S rlen;
    
    if (round->rule == NULL) return 0;
    
    rlen = -1;
    ct   = 0;
    rptr = round->rptr;
    used = round->used;
    while (used > 0) {
        cur = *rptr++;
        used--;
        ct++;
        if (rptr >= round->eptr) rptr = round->bptr;
        if (rlen == -1) {                                   /* search flags */
            if (cur == round->rule->c_flags) {
                rlen = 0;
                pre  = 0;
            }
            continue;
        } else if (rlen == 0) {
            if (cur == round->rule->c_flags) continue;
        } else {
            if (cur == round->rule->c_flags) {
                round->rptr  = rptr;
                round->used -= ct;
                return rlen;
            }
        }
        if (pre == round->rule->c_convert0) {               /* search convert character */
            if (cur == round->rule->c_convert1)             /* c_flags    = c_convert0 + c_convert1 */
                *dptr++ = round->rule->c_flags;
            else if (cur == round->rule->c_convert2)        /* c_convert0 = c_convert0 + c_convert2 */
                *dptr++ = round->rule->c_convert0;
            else {
                round->rptr  = rptr;                        /* detect error frame! */
                round->used -= ct;
                rlen = -1;
                continue;
            }
        } else {
            if (cur != round->rule->c_convert0)             /* search convert character */
                *dptr++ = cur;
            rlen++;
        }
        pre = cur;
        if (rlen >= maxlen) {
            round->rptr  = rptr;
            round->used -= ct;
            rlen = -1;
            continue;
        }
    }
    return 0;
}