Function reginsert

v2/engine/regexp.c:694–718

- reginsert - insert an operator in front of already-emitted operand * * Means relocating the operand. */

 * Means relocating the operand.
 */
static void
reginsert(
    char op,
    char *opnd )
{
    register char *src;
    register char *dst;
    register char *place;

    if (regcode == &regdummy) {
        regsize += 3;
        return;
    }

    src = regcode;
    regcode += 3;
    dst = regcode;
    while (src > opnd)
        *--dst = *--src;

    place = opnd;       /* Op node, where operand used to be. */
    *place++ = op;
    *place++ = '\0';
    *place++ = '\0';
}

/*
 - regtail - set the next-pointer at the end of a node chain