Function bi_reverse

zlib/trees.c:1091–1099

=========================================================================== * Reverse the first len bits of a code, using straightforward code (a faster * method would use a table) * IN assertion: 1 <= len <= 15 */

 * IN assertion: 1 <= len <= 15
 */
local unsigned bi_reverse(unsigned code, int len)
{
    register unsigned res = 0;
    do {
        res |= code & 1;
        code >>= 1, res <<= 1;
    } while (--len > 0);
    return res >> 1;
}

/* ===========================================================================
 * Flush the bit buffer, keeping at most 7 bits in it.