/
deflate_p.h
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/
deflate_p.h
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/* deflate_p.h -- Private inline functions and macros shared with more than
* one deflate method
*
* Copyright (C) 1995-2024 Jean-loup Gailly and Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*
*/
#ifndef DEFLATE_P_H
#define DEFLATE_P_H
/* Forward declare common non-inlined functions declared in deflate.c */
#ifdef ZLIB_DEBUG
/* ===========================================================================
* Check that the match at match_start is indeed a match.
*/
static inline void check_match(deflate_state *s, Pos start, Pos match, int length) {
/* check that the match length is valid*/
if (length < STD_MIN_MATCH || length > STD_MAX_MATCH) {
fprintf(stderr, " start %u, match %u, length %d\n", start, match, length);
z_error("invalid match length");
}
/* check that the match isn't at the same position as the start string */
if (match == start) {
fprintf(stderr, " start %u, match %u, length %d\n", start, match, length);
z_error("invalid match position");
}
/* check that the match is indeed a match */
if (memcmp(s->window + match, s->window + start, length) != 0) {
int32_t i = 0;
fprintf(stderr, " start %u, match %u, length %d\n", start, match, length);
do {
fprintf(stderr, " %03d: match [%02x] start [%02x]\n", i++,
s->window[match++], s->window[start++]);
} while (--length != 0);
z_error("invalid match");
}
if (z_verbose > 1) {
fprintf(stderr, "\\[%u,%d]", start-match, length);
do {
putc(s->window[start++], stderr);
} while (--length != 0);
}
}
#else
#define check_match(s, start, match, length)
#endif
Z_INTERNAL void PREFIX(flush_pending)(PREFIX3(stream) *strm);
Z_INTERNAL unsigned PREFIX(read_buf)(PREFIX3(stream) *strm, unsigned char *buf, unsigned size);
/* ===========================================================================
* Save the match info and tally the frequency counts. Return true if
* the current block must be flushed.
*/
extern const unsigned char Z_INTERNAL zng_length_code[];
extern const unsigned char Z_INTERNAL zng_dist_code[];
static inline int zng_tr_tally_lit(deflate_state *s, unsigned char c) {
/* c is the unmatched char */
#ifdef LIT_MEM
s->d_buf[s->sym_next] = 0;
s->l_buf[s->sym_next++] = c;
#else
s->sym_buf[s->sym_next++] = 0;
s->sym_buf[s->sym_next++] = 0;
s->sym_buf[s->sym_next++] = c;
#endif
s->dyn_ltree[c].Freq++;
Tracevv((stderr, "%c", c));
Assert(c <= (STD_MAX_MATCH-STD_MIN_MATCH), "zng_tr_tally: bad literal");
return (s->sym_next == s->sym_end);
}
static inline int zng_tr_tally_dist(deflate_state* s, uint32_t dist, uint32_t len) {
/* dist: distance of matched string */
/* len: match length-STD_MIN_MATCH */
#ifdef LIT_MEM
s->d_buf[s->sym_next] = dist;
s->l_buf[s->sym_next++] = len;
#else
s->sym_buf[s->sym_next++] = (uint8_t)(dist);
s->sym_buf[s->sym_next++] = (uint8_t)(dist >> 8);
s->sym_buf[s->sym_next++] = (uint8_t)len;
#endif
s->matches++;
dist--;
Assert(dist < MAX_DIST(s) && (uint16_t)d_code(dist) < (uint16_t)D_CODES,
"zng_tr_tally: bad match");
s->dyn_ltree[zng_length_code[len] + LITERALS + 1].Freq++;
s->dyn_dtree[d_code(dist)].Freq++;
return (s->sym_next == s->sym_end);
}
/* ===========================================================================
* Flush the current block, with given end-of-file flag.
* IN assertion: strstart is set to the end of the current match.
*/
#define FLUSH_BLOCK_ONLY(s, last) { \
zng_tr_flush_block(s, (s->block_start >= 0 ? \
(char *)&s->window[(unsigned)s->block_start] : \
NULL), \
(uint32_t)((int)s->strstart - s->block_start), \
(last)); \
s->block_start = (int)s->strstart; \
PREFIX(flush_pending)(s->strm); \
}
/* Same but force premature exit if necessary. */
#define FLUSH_BLOCK(s, last) { \
FLUSH_BLOCK_ONLY(s, last); \
if (s->strm->avail_out == 0) return (last) ? finish_started : need_more; \
}
/* Maximum stored block length in deflate format (not including header). */
#define MAX_STORED 65535
/* Compression function. Returns the block state after the call. */
typedef block_state (*compress_func) (deflate_state *s, int flush);
/* Match function. Returns the longest match. */
typedef uint32_t (*match_func) (deflate_state *const s, Pos cur_match);
#endif