sys/libkern/zlib.c

132 #define MIN_MATCH  3
400      * step. It must be such that after MIN_MATCH steps, the oldest
402      *   hash_shift * MIN_MATCH >= hash_bits
528 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
530  * See deflate.c for comments about the MIN_MATCH+1.
658 #define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)
660  * See deflate.c for comments about the MIN_MATCH+1.
690 /* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4
716  *    input characters and the first MIN_MATCH bytes of str are valid
717  *    (except for the last MIN_MATCH-1 bytes of the input file).
720    (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
804     s->hash_shift =  ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);
851     if (length < MIN_MATCH) return Z_OK;
868     for (n = 0; n <= length - MIN_MATCH; n++) {
1259     s->match_length = s->prev_length = MIN_MATCH-1;
1533         if (s->lookahead >= MIN_MATCH) {
1536 #if MIN_MATCH != 3
1537             Call UPDATE_HASH() MIN_MATCH-3 more times
1540         /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
1645          * for the next match, plus MIN_MATCH bytes to insert the
1659         if (s->lookahead >= MIN_MATCH) {
1664          * At this point we have always match_length < MIN_MATCH
1676         if (s->match_length >= MIN_MATCH) {
1680                                s->match_length - MIN_MATCH);
1688                 s->lookahead >= MIN_MATCH) {
1694                      * always MIN_MATCH bytes ahead.
1703 #if MIN_MATCH != 3
1704                 Call UPDATE_HASH() MIN_MATCH-3 more times
1706                 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not
1739          * for the next match, plus MIN_MATCH bytes to insert the
1753         if (s->lookahead >= MIN_MATCH) {
1760         s->match_length = MIN_MATCH-1;
1774                  (s->match_length == MIN_MATCH &&
1777                 /* If prev_match is also MIN_MATCH, match_start is garbage
1780                 s->match_length = MIN_MATCH-1;
1786         if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
1787             uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
1793                                s->prev_length - MIN_MATCH);
1808             s->match_length = MIN_MATCH-1;
1946 local uch length_code[MAX_MATCH-MIN_MATCH+1];
1947 /* length code for each normalized match length (0 == MIN_MATCH) */
1950 /* First normalized length for each code (0 = MIN_MATCH) */
2807     unsigned lc;    /* match length-MIN_MATCH or unmatched char (if dist==0) */
2816         /* Here, lc is the match length - MIN_MATCH */
2819                (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
2870             /* Here, lc is the match length - MIN_MATCH */