src/dle.c


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#include "dle.h"

/* Those nifty DLE-sequences */
#define DLE 0x10
#define ETX 0x03
#define DC4 0x14

size_t dle_decode(uint8_t* s, size_t ls, uint8_t* d, size_t *ld, void (*dle_func) (uint8_t c, void *user), void *user, int *dle_flag) {
    size_t ns, nd;
    assert(s && ls && d && ld && *ld && dle_flag);

    for (ns = nd = 0; ns < ls && nd < *ld; ns++) {
        
        if (*dle_flag) {
            if (s[ns] == DLE)
                d[nd++] = DLE;
            else {
                if (dle_func)
                    dle_func(s[ns], user);
            }
            
            *dle_flag = 0;
        } else {
            if (s[ns] == DLE)
                *dle_flag = 1;
            else
                d[nd++] = s[ns];
        }
    }

    *ld = nd;
    return ns;
}

size_t dle_encode(uint8_t* s, size_t ls, uint8_t* d, size_t *ld) {
    size_t ns, nd;

    for (ns = nd = 0; ns < ls && nd < *ld; ns++) {
        if (s[ns] == DLE)
            d[nd++] = DLE;

        d[nd++] = s[ns];
    }

    *ld = nd;
    return ns;
}