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 void check_match(deflate_state *s, Pos start, Pos match, int length);
16 #else
17 #define check_match(s, start, match, length)
18 #endif
19 void flush_pending(PREFIX3(stream) *strm);
20
21 /* ===========================================================================
22 * Save the match info and tally the frequency counts. Return true if
23 * the current block must be flushed.
24 */
25
26 extern const unsigned char Z_INTERNAL zng_length_code[];
27 extern const unsigned char Z_INTERNAL zng_dist_code[];
28
zng_tr_tally_lit(deflate_state * s,unsigned char c)29 static inline int zng_tr_tally_lit(deflate_state *s, unsigned char c) {
30 /* c is the unmatched char */
31 s->sym_buf[s->sym_next++] = 0;
32 s->sym_buf[s->sym_next++] = 0;
33 s->sym_buf[s->sym_next++] = c;
34 s->dyn_ltree[c].Freq++;
35 Tracevv((stderr, "%c", c));
36 Assert(c <= (MAX_MATCH-MIN_MATCH), "zng_tr_tally: bad literal");
37 return (s->sym_next == s->sym_end);
38 }
39
zng_tr_tally_dist(deflate_state * s,unsigned dist,unsigned char len)40 static inline int zng_tr_tally_dist(deflate_state *s, unsigned dist, unsigned char len) {
41 /* dist: distance of matched string */
42 /* len: match length-MIN_MATCH */
43 s->sym_buf[s->sym_next++] = (uint8_t)(dist);
44 s->sym_buf[s->sym_next++] = (uint8_t)(dist >> 8);
45 s->sym_buf[s->sym_next++] = len;
46 s->matches++;
47 dist--;
48 Assert((uint16_t)dist < (uint16_t)MAX_DIST(s) &&
49 (uint16_t)d_code(dist) < (uint16_t)D_CODES, "zng_tr_tally: bad match");
50
51 s->dyn_ltree[zng_length_code[len]+LITERALS+1].Freq++;
52 s->dyn_dtree[d_code(dist)].Freq++;
53 return (s->sym_next == s->sym_end);
54 }
55
56 /* ===========================================================================
57 * Flush the current block, with given end-of-file flag.
58 * IN assertion: strstart is set to the end of the current match.
59 */
60 #define FLUSH_BLOCK_ONLY(s, last) { \
61 zng_tr_flush_block(s, (s->block_start >= 0 ? \
62 (char *)&s->window[(unsigned)s->block_start] : \
63 NULL), \
64 (uint32_t)((int)s->strstart - s->block_start), \
65 (last)); \
66 s->block_start = (int)s->strstart; \
67 flush_pending(s->strm); \
68 }
69
70 /* Same but force premature exit if necessary. */
71 #define FLUSH_BLOCK(s, last) { \
72 FLUSH_BLOCK_ONLY(s, last); \
73 if (s->strm->avail_out == 0) return (last) ? finish_started : need_more; \
74 }
75
76 /* Maximum stored block length in deflate format (not including header). */
77 #define MAX_STORED 65535
78
79 /* Minimum of a and b. */
80 #define MIN(a, b) ((a) > (b) ? (b) : (a))
81
82 #endif
83