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,uint32_t dist,uint32_t len)40 static inline int zng_tr_tally_dist(deflate_state *s, uint32_t dist, uint32_t 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++] = (uint8_t)len;
46     s->matches++;
47     dist--;
48     Assert(dist < MAX_DIST(s) && (uint16_t)d_code(dist) < (uint16_t)D_CODES,
49         "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 #endif
80