1 /* deflate_p.h -- Private inline functions and macros shared with more than
2 * one deflate method
3 *
4 * Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler
5 * For conditions of distribution and use, see copyright notice in zlib.h
6 *
7 */
8
9 #ifndef DEFLATE_P_H
10 #define DEFLATE_P_H
11
12 /* Forward declare common non-inlined functions declared in deflate.c */
13
14 #ifdef ZLIB_DEBUG
15 /* ===========================================================================
16 * Check that the match at match_start is indeed a match.
17 */
check_match(deflate_state * s,Pos start,Pos match,int length)18 static inline void check_match(deflate_state *s, Pos start, Pos match, int length) {
19 /* check that the match length is valid*/
20 if (length < STD_MIN_MATCH || length > STD_MAX_MATCH) {
21 fprintf(stderr, " start %u, match %u, length %d\n", start, match, length);
22 z_error("invalid match length");
23 }
24 /* check that the match isn't at the same position as the start string */
25 if (match == start) {
26 fprintf(stderr, " start %u, match %u, length %d\n", start, match, length);
27 z_error("invalid match position");
28 }
29 /* check that the match is indeed a match */
30 if (memcmp(s->window + match, s->window + start, length) != 0) {
31 int32_t i = 0;
32 fprintf(stderr, " start %u, match %u, length %d\n", start, match, length);
33 do {
34 fprintf(stderr, " %03d: match [%02x] start [%02x]\n", i++,
35 s->window[match++], s->window[start++]);
36 } while (--length != 0);
37 z_error("invalid match");
38 }
39 if (z_verbose > 1) {
40 fprintf(stderr, "\\[%u,%d]", start-match, length);
41 do {
42 putc(s->window[start++], stderr);
43 } while (--length != 0);
44 }
45 }
46 #else
47 #define check_match(s, start, match, length)
48 #endif
49
50 Z_INTERNAL void PREFIX(flush_pending)(PREFIX3(stream) *strm);
51 Z_INTERNAL unsigned read_buf(PREFIX3(stream) *strm, unsigned char *buf, unsigned size);
52
53 /* ===========================================================================
54 * Save the match info and tally the frequency counts. Return true if
55 * the current block must be flushed.
56 */
57
58 extern const unsigned char Z_INTERNAL zng_length_code[];
59 extern const unsigned char Z_INTERNAL zng_dist_code[];
60
zng_tr_tally_lit(deflate_state * s,unsigned char c)61 static inline int zng_tr_tally_lit(deflate_state *s, unsigned char c) {
62 /* c is the unmatched char */
63 s->sym_buf[s->sym_next++] = 0;
64 s->sym_buf[s->sym_next++] = 0;
65 s->sym_buf[s->sym_next++] = c;
66 s->dyn_ltree[c].Freq++;
67 Tracevv((stderr, "%c", c));
68 Assert(c <= (STD_MAX_MATCH-STD_MIN_MATCH), "zng_tr_tally: bad literal");
69 return (s->sym_next == s->sym_end);
70 }
71
zng_tr_tally_dist(deflate_state * s,uint32_t dist,uint32_t len)72 static inline int zng_tr_tally_dist(deflate_state *s, uint32_t dist, uint32_t len) {
73 /* dist: distance of matched string */
74 /* len: match length-STD_MIN_MATCH */
75 s->sym_buf[s->sym_next++] = (uint8_t)(dist);
76 s->sym_buf[s->sym_next++] = (uint8_t)(dist >> 8);
77 s->sym_buf[s->sym_next++] = (uint8_t)len;
78 s->matches++;
79 dist--;
80 Assert(dist < MAX_DIST(s) && (uint16_t)d_code(dist) < (uint16_t)D_CODES,
81 "zng_tr_tally: bad match");
82
83 s->dyn_ltree[zng_length_code[len]+LITERALS+1].Freq++;
84 s->dyn_dtree[d_code(dist)].Freq++;
85 return (s->sym_next == s->sym_end);
86 }
87
88 /* ===========================================================================
89 * Flush the current block, with given end-of-file flag.
90 * IN assertion: strstart is set to the end of the current match.
91 */
92 #define FLUSH_BLOCK_ONLY(s, last) { \
93 zng_tr_flush_block(s, (s->block_start >= 0 ? \
94 (char *)&s->window[(unsigned)s->block_start] : \
95 NULL), \
96 (uint32_t)((int)s->strstart - s->block_start), \
97 (last)); \
98 s->block_start = (int)s->strstart; \
99 PREFIX(flush_pending)(s->strm); \
100 }
101
102 /* Same but force premature exit if necessary. */
103 #define FLUSH_BLOCK(s, last) { \
104 FLUSH_BLOCK_ONLY(s, last); \
105 if (s->strm->avail_out == 0) return (last) ? finish_started : need_more; \
106 }
107
108 /* Maximum stored block length in deflate format (not including header). */
109 #define MAX_STORED 65535
110
111 /* Compression function. Returns the block state after the call. */
112 typedef block_state (*compress_func) (deflate_state *s, int flush);
113 /* Match function. Returns the longest match. */
114 typedef uint32_t (*match_func) (deflate_state *const s, Pos cur_match);
115
116 #endif
117