/* deflate.c -- compress data using the deflation algorithm
- * Copyright (C) 1995-2022 Jean-loup Gailly and Mark Adler
+ * Copyright (C) 1995-2024 Jean-loup Gailly and Mark Adler
* For conditions of distribution and use, see copyright notice in zlib.h
*/
#include "deflate.h"
const char deflate_copyright[] =
- " deflate 1.2.13 Copyright 1995-2022 Jean-loup Gailly and Mark Adler ";
+ " deflate 1.3.1 Copyright 1995-2024 Jean-loup Gailly and Mark Adler ";
/*
If you use the zlib library in a product, an acknowledgment is welcome
in the documentation of your product. If for some reason you cannot
copyright string in the executable of your product.
*/
-/* ===========================================================================
- * Function prototypes.
- */
typedef enum {
need_more, /* block not completed, need more input or more output */
block_done, /* block flush performed */
finish_done /* finish done, accept no more input or output */
} block_state;
-typedef block_state (*compress_func) OF((deflate_state *s, int flush));
+typedef block_state (*compress_func)(deflate_state *s, int flush);
/* Compression function. Returns the block state after the call. */
-local int deflateStateCheck OF((z_streamp strm));
-local void slide_hash OF((deflate_state *s));
-local void fill_window OF((deflate_state *s));
-local block_state deflate_stored OF((deflate_state *s, int flush));
-local block_state deflate_fast OF((deflate_state *s, int flush));
+local block_state deflate_stored(deflate_state *s, int flush);
+local block_state deflate_fast(deflate_state *s, int flush);
#ifndef FASTEST
-local block_state deflate_slow OF((deflate_state *s, int flush));
-#endif
-local block_state deflate_rle OF((deflate_state *s, int flush));
-local block_state deflate_huff OF((deflate_state *s, int flush));
-local void lm_init OF((deflate_state *s));
-local void putShortMSB OF((deflate_state *s, uInt b));
-local void flush_pending OF((z_streamp strm));
-local unsigned read_buf OF((z_streamp strm, Bytef *buf, unsigned size));
-local uInt longest_match OF((deflate_state *s, IPos cur_match));
-
-#ifdef ZLIB_DEBUG
-local void check_match OF((deflate_state *s, IPos start, IPos match,
- int length));
+local block_state deflate_slow(deflate_state *s, int flush);
#endif
+local block_state deflate_rle(deflate_state *s, int flush);
+local block_state deflate_huff(deflate_state *s, int flush);
/* ===========================================================================
* Local data
* bit values at the expense of memory usage). We slide even when level == 0 to
* keep the hash table consistent if we switch back to level > 0 later.
*/
-local void slide_hash(s)
- deflate_state *s;
-{
+#if defined(__has_feature)
+# if __has_feature(memory_sanitizer)
+ __attribute__((no_sanitize("memory")))
+# endif
+#endif
+local void slide_hash(deflate_state *s) {
unsigned n, m;
Posf *p;
uInt wsize = s->w_size;
#endif
}
+/* ===========================================================================
+ * Read a new buffer from the current input stream, update the adler32
+ * and total number of bytes read. All deflate() input goes through
+ * this function so some applications may wish to modify it to avoid
+ * allocating a large strm->next_in buffer and copying from it.
+ * (See also flush_pending()).
+ */
+local unsigned read_buf(z_streamp strm, Bytef *buf, unsigned size) {
+ unsigned len = strm->avail_in;
+
+ if (len > size) len = size;
+ if (len == 0) return 0;
+
+ strm->avail_in -= len;
+
+ zmemcpy(buf, strm->next_in, len);
+ if (strm->state->wrap == 1) {
+ strm->adler = adler32(strm->adler, buf, len);
+ }
+#ifdef GZIP
+ else if (strm->state->wrap == 2) {
+ strm->adler = crc32(strm->adler, buf, len);
+ }
+#endif
+ strm->next_in += len;
+ strm->total_in += len;
+
+ return len;
+}
+
+/* ===========================================================================
+ * Fill the window when the lookahead becomes insufficient.
+ * Updates strstart and lookahead.
+ *
+ * IN assertion: lookahead < MIN_LOOKAHEAD
+ * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
+ * At least one byte has been read, or avail_in == 0; reads are
+ * performed for at least two bytes (required for the zip translate_eol
+ * option -- not supported here).
+ */
+local void fill_window(deflate_state *s) {
+ unsigned n;
+ unsigned more; /* Amount of free space at the end of the window. */
+ uInt wsize = s->w_size;
+
+ Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead");
+
+ do {
+ more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
+
+ /* Deal with !@#$% 64K limit: */
+ if (sizeof(int) <= 2) {
+ if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
+ more = wsize;
+
+ } else if (more == (unsigned)(-1)) {
+ /* Very unlikely, but possible on 16 bit machine if
+ * strstart == 0 && lookahead == 1 (input done a byte at time)
+ */
+ more--;
+ }
+ }
+
+ /* If the window is almost full and there is insufficient lookahead,
+ * move the upper half to the lower one to make room in the upper half.
+ */
+ if (s->strstart >= wsize + MAX_DIST(s)) {
+
+ zmemcpy(s->window, s->window + wsize, (unsigned)wsize - more);
+ s->match_start -= wsize;
+ s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
+ s->block_start -= (long) wsize;
+ if (s->insert > s->strstart)
+ s->insert = s->strstart;
+ slide_hash(s);
+ more += wsize;
+ }
+ if (s->strm->avail_in == 0) break;
+
+ /* If there was no sliding:
+ * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
+ * more == window_size - lookahead - strstart
+ * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
+ * => more >= window_size - 2*WSIZE + 2
+ * In the BIG_MEM or MMAP case (not yet supported),
+ * window_size == input_size + MIN_LOOKAHEAD &&
+ * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
+ * Otherwise, window_size == 2*WSIZE so more >= 2.
+ * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
+ */
+ Assert(more >= 2, "more < 2");
+
+ n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
+ s->lookahead += n;
+
+ /* Initialize the hash value now that we have some input: */
+ if (s->lookahead + s->insert >= MIN_MATCH) {
+ uInt str = s->strstart - s->insert;
+ s->ins_h = s->window[str];
+ UPDATE_HASH(s, s->ins_h, s->window[str + 1]);
+#if MIN_MATCH != 3
+ Call UPDATE_HASH() MIN_MATCH-3 more times
+#endif
+ while (s->insert) {
+ UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]);
+#ifndef FASTEST
+ s->prev[str & s->w_mask] = s->head[s->ins_h];
+#endif
+ s->head[s->ins_h] = (Pos)str;
+ str++;
+ s->insert--;
+ if (s->lookahead + s->insert < MIN_MATCH)
+ break;
+ }
+ }
+ /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
+ * but this is not important since only literal bytes will be emitted.
+ */
+
+ } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
+
+ /* If the WIN_INIT bytes after the end of the current data have never been
+ * written, then zero those bytes in order to avoid memory check reports of
+ * the use of uninitialized (or uninitialised as Julian writes) bytes by
+ * the longest match routines. Update the high water mark for the next
+ * time through here. WIN_INIT is set to MAX_MATCH since the longest match
+ * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead.
+ */
+ if (s->high_water < s->window_size) {
+ ulg curr = s->strstart + (ulg)(s->lookahead);
+ ulg init;
+
+ if (s->high_water < curr) {
+ /* Previous high water mark below current data -- zero WIN_INIT
+ * bytes or up to end of window, whichever is less.
+ */
+ init = s->window_size - curr;
+ if (init > WIN_INIT)
+ init = WIN_INIT;
+ zmemzero(s->window + curr, (unsigned)init);
+ s->high_water = curr + init;
+ }
+ else if (s->high_water < (ulg)curr + WIN_INIT) {
+ /* High water mark at or above current data, but below current data
+ * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up
+ * to end of window, whichever is less.
+ */
+ init = (ulg)curr + WIN_INIT - s->high_water;
+ if (init > s->window_size - s->high_water)
+ init = s->window_size - s->high_water;
+ zmemzero(s->window + s->high_water, (unsigned)init);
+ s->high_water += init;
+ }
+ }
+
+ Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD,
+ "not enough room for search");
+}
+
/* ========================================================================= */
-int ZEXPORT deflateInit_(strm, level, version, stream_size)
- z_streamp strm;
- int level;
- const char *version;
- int stream_size;
-{
+int ZEXPORT deflateInit_(z_streamp strm, int level, const char *version,
+ int stream_size) {
return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,
Z_DEFAULT_STRATEGY, version, stream_size);
/* To do: ignore strm->next_in if we use it as window */
}
/* ========================================================================= */
-int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,
- version, stream_size)
- z_streamp strm;
- int level;
- int method;
- int windowBits;
- int memLevel;
- int strategy;
- const char *version;
- int stream_size;
-{
+int ZEXPORT deflateInit2_(z_streamp strm, int level, int method,
+ int windowBits, int memLevel, int strategy,
+ const char *version, int stream_size) {
deflate_state *s;
int wrap = 1;
static const char my_version[] = ZLIB_VERSION;
* symbols from which it is being constructed.
*/
- s->pending_buf = (uchf *) ZALLOC(strm, s->lit_bufsize, 4);
+ s->pending_buf = (uchf *) ZALLOC(strm, s->lit_bufsize, LIT_BUFS);
s->pending_buf_size = (ulg)s->lit_bufsize * 4;
if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||
deflateEnd (strm);
return Z_MEM_ERROR;
}
+#ifdef LIT_MEM
+ s->d_buf = (ushf *)(s->pending_buf + (s->lit_bufsize << 1));
+ s->l_buf = s->pending_buf + (s->lit_bufsize << 2);
+ s->sym_end = s->lit_bufsize - 1;
+#else
s->sym_buf = s->pending_buf + s->lit_bufsize;
s->sym_end = (s->lit_bufsize - 1) * 3;
+#endif
/* We avoid equality with lit_bufsize*3 because of wraparound at 64K
* on 16 bit machines and because stored blocks are restricted to
* 64K-1 bytes.
/* =========================================================================
* Check for a valid deflate stream state. Return 0 if ok, 1 if not.
*/
-local int deflateStateCheck(strm)
- z_streamp strm;
-{
+local int deflateStateCheck(z_streamp strm) {
deflate_state *s;
if (strm == Z_NULL ||
strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0)
}
/* ========================================================================= */
-int ZEXPORT deflateSetDictionary(strm, dictionary, dictLength)
- z_streamp strm;
- const Bytef *dictionary;
- uInt dictLength;
-{
+int ZEXPORT deflateSetDictionary(z_streamp strm, const Bytef *dictionary,
+ uInt dictLength) {
deflate_state *s;
uInt str, n;
int wrap;
}
/* ========================================================================= */
-int ZEXPORT deflateGetDictionary(strm, dictionary, dictLength)
- z_streamp strm;
- Bytef *dictionary;
- uInt *dictLength;
-{
+int ZEXPORT deflateGetDictionary(z_streamp strm, Bytef *dictionary,
+ uInt *dictLength) {
deflate_state *s;
uInt len;
}
/* ========================================================================= */
-int ZEXPORT deflateResetKeep(strm)
- z_streamp strm;
-{
+int ZEXPORT deflateResetKeep(z_streamp strm) {
deflate_state *s;
if (deflateStateCheck(strm)) {
return Z_OK;
}
+/* ===========================================================================
+ * Initialize the "longest match" routines for a new zlib stream
+ */
+local void lm_init(deflate_state *s) {
+ s->window_size = (ulg)2L*s->w_size;
+
+ CLEAR_HASH(s);
+
+ /* Set the default configuration parameters:
+ */
+ s->max_lazy_match = configuration_table[s->level].max_lazy;
+ s->good_match = configuration_table[s->level].good_length;
+ s->nice_match = configuration_table[s->level].nice_length;
+ s->max_chain_length = configuration_table[s->level].max_chain;
+
+ s->strstart = 0;
+ s->block_start = 0L;
+ s->lookahead = 0;
+ s->insert = 0;
+ s->match_length = s->prev_length = MIN_MATCH-1;
+ s->match_available = 0;
+ s->ins_h = 0;
+}
+
/* ========================================================================= */
-int ZEXPORT deflateReset(strm)
- z_streamp strm;
-{
+int ZEXPORT deflateReset(z_streamp strm) {
int ret;
ret = deflateResetKeep(strm);
}
/* ========================================================================= */
-int ZEXPORT deflateSetHeader(strm, head)
- z_streamp strm;
- gz_headerp head;
-{
+int ZEXPORT deflateSetHeader(z_streamp strm, gz_headerp head) {
if (deflateStateCheck(strm) || strm->state->wrap != 2)
return Z_STREAM_ERROR;
strm->state->gzhead = head;
}
/* ========================================================================= */
-int ZEXPORT deflatePending(strm, pending, bits)
- unsigned *pending;
- int *bits;
- z_streamp strm;
-{
+int ZEXPORT deflatePending(z_streamp strm, unsigned *pending, int *bits) {
if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
if (pending != Z_NULL)
*pending = strm->state->pending;
}
/* ========================================================================= */
-int ZEXPORT deflatePrime(strm, bits, value)
- z_streamp strm;
- int bits;
- int value;
-{
+int ZEXPORT deflatePrime(z_streamp strm, int bits, int value) {
deflate_state *s;
int put;
if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
s = strm->state;
+#ifdef LIT_MEM
+ if (bits < 0 || bits > 16 ||
+ (uchf *)s->d_buf < s->pending_out + ((Buf_size + 7) >> 3))
+ return Z_BUF_ERROR;
+#else
if (bits < 0 || bits > 16 ||
s->sym_buf < s->pending_out + ((Buf_size + 7) >> 3))
return Z_BUF_ERROR;
+#endif
do {
put = Buf_size - s->bi_valid;
if (put > bits)
}
/* ========================================================================= */
-int ZEXPORT deflateParams(strm, level, strategy)
- z_streamp strm;
- int level;
- int strategy;
-{
+int ZEXPORT deflateParams(z_streamp strm, int level, int strategy) {
deflate_state *s;
compress_func func;
}
/* ========================================================================= */
-int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain)
- z_streamp strm;
- int good_length;
- int max_lazy;
- int nice_length;
- int max_chain;
-{
+int ZEXPORT deflateTune(z_streamp strm, int good_length, int max_lazy,
+ int nice_length, int max_chain) {
deflate_state *s;
if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
*
* Shifts are used to approximate divisions, for speed.
*/
-uLong ZEXPORT deflateBound(strm, sourceLen)
- z_streamp strm;
- uLong sourceLen;
-{
+uLong ZEXPORT deflateBound(z_streamp strm, uLong sourceLen) {
deflate_state *s;
uLong fixedlen, storelen, wraplen;
/* if not default parameters, return one of the conservative bounds */
if (s->w_bits != 15 || s->hash_bits != 8 + 7)
- return (s->w_bits <= s->hash_bits ? fixedlen : storelen) + wraplen;
+ return (s->w_bits <= s->hash_bits && s->level ? fixedlen : storelen) +
+ wraplen;
/* default settings: return tight bound for that case -- ~0.03% overhead
plus a small constant */
* IN assertion: the stream state is correct and there is enough room in
* pending_buf.
*/
-local void putShortMSB(s, b)
- deflate_state *s;
- uInt b;
-{
+local void putShortMSB(deflate_state *s, uInt b) {
put_byte(s, (Byte)(b >> 8));
put_byte(s, (Byte)(b & 0xff));
}
* applications may wish to modify it to avoid allocating a large
* strm->next_out buffer and copying into it. (See also read_buf()).
*/
-local void flush_pending(strm)
- z_streamp strm;
-{
+local void flush_pending(z_streamp strm) {
unsigned len;
deflate_state *s = strm->state;
} while (0)
/* ========================================================================= */
-int ZEXPORT deflate(strm, flush)
- z_streamp strm;
- int flush;
-{
+int ZEXPORT deflate(z_streamp strm, int flush) {
int old_flush; /* value of flush param for previous deflate call */
deflate_state *s;
}
/* ========================================================================= */
-int ZEXPORT deflateEnd(strm)
- z_streamp strm;
-{
+int ZEXPORT deflateEnd(z_streamp strm) {
int status;
if (deflateStateCheck(strm)) return Z_STREAM_ERROR;
* To simplify the source, this is not supported for 16-bit MSDOS (which
* doesn't have enough memory anyway to duplicate compression states).
*/
-int ZEXPORT deflateCopy(dest, source)
- z_streamp dest;
- z_streamp source;
-{
+int ZEXPORT deflateCopy(z_streamp dest, z_streamp source) {
#ifdef MAXSEG_64K
+ (void)dest;
+ (void)source;
return Z_STREAM_ERROR;
#else
deflate_state *ds;
ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));
ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos));
ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos));
- ds->pending_buf = (uchf *) ZALLOC(dest, ds->lit_bufsize, 4);
+ ds->pending_buf = (uchf *) ZALLOC(dest, ds->lit_bufsize, LIT_BUFS);
if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||
ds->pending_buf == Z_NULL) {
zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));
zmemcpy((voidpf)ds->prev, (voidpf)ss->prev, ds->w_size * sizeof(Pos));
zmemcpy((voidpf)ds->head, (voidpf)ss->head, ds->hash_size * sizeof(Pos));
- zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);
+ zmemcpy(ds->pending_buf, ss->pending_buf, ds->lit_bufsize * LIT_BUFS);
ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);
+#ifdef LIT_MEM
+ ds->d_buf = (ushf *)(ds->pending_buf + (ds->lit_bufsize << 1));
+ ds->l_buf = ds->pending_buf + (ds->lit_bufsize << 2);
+#else
ds->sym_buf = ds->pending_buf + ds->lit_bufsize;
+#endif
ds->l_desc.dyn_tree = ds->dyn_ltree;
ds->d_desc.dyn_tree = ds->dyn_dtree;
#endif /* MAXSEG_64K */
}
-/* ===========================================================================
- * Read a new buffer from the current input stream, update the adler32
- * and total number of bytes read. All deflate() input goes through
- * this function so some applications may wish to modify it to avoid
- * allocating a large strm->next_in buffer and copying from it.
- * (See also flush_pending()).
- */
-local unsigned read_buf(strm, buf, size)
- z_streamp strm;
- Bytef *buf;
- unsigned size;
-{
- unsigned len = strm->avail_in;
-
- if (len > size) len = size;
- if (len == 0) return 0;
-
- strm->avail_in -= len;
-
- zmemcpy(buf, strm->next_in, len);
- if (strm->state->wrap == 1) {
- strm->adler = adler32(strm->adler, buf, len);
- }
-#ifdef GZIP
- else if (strm->state->wrap == 2) {
- strm->adler = crc32(strm->adler, buf, len);
- }
-#endif
- strm->next_in += len;
- strm->total_in += len;
-
- return len;
-}
-
-/* ===========================================================================
- * Initialize the "longest match" routines for a new zlib stream
- */
-local void lm_init(s)
- deflate_state *s;
-{
- s->window_size = (ulg)2L*s->w_size;
-
- CLEAR_HASH(s);
-
- /* Set the default configuration parameters:
- */
- s->max_lazy_match = configuration_table[s->level].max_lazy;
- s->good_match = configuration_table[s->level].good_length;
- s->nice_match = configuration_table[s->level].nice_length;
- s->max_chain_length = configuration_table[s->level].max_chain;
-
- s->strstart = 0;
- s->block_start = 0L;
- s->lookahead = 0;
- s->insert = 0;
- s->match_length = s->prev_length = MIN_MATCH-1;
- s->match_available = 0;
- s->ins_h = 0;
-}
-
#ifndef FASTEST
/* ===========================================================================
* Set match_start to the longest match starting at the given string and
* string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
* OUT assertion: the match length is not greater than s->lookahead.
*/
-local uInt longest_match(s, cur_match)
- deflate_state *s;
- IPos cur_match; /* current match */
-{
+local uInt longest_match(deflate_state *s, IPos cur_match) {
unsigned chain_length = s->max_chain_length;/* max hash chain length */
register Bytef *scan = s->window + s->strstart; /* current string */
register Bytef *match; /* matched string */
/* ---------------------------------------------------------------------------
* Optimized version for FASTEST only
*/
-local uInt longest_match(s, cur_match)
- deflate_state *s;
- IPos cur_match; /* current match */
-{
+local uInt longest_match(deflate_state *s, IPos cur_match) {
register Bytef *scan = s->window + s->strstart; /* current string */
register Bytef *match; /* matched string */
register int len; /* length of current match */
/* ===========================================================================
* Check that the match at match_start is indeed a match.
*/
-local void check_match(s, start, match, length)
- deflate_state *s;
- IPos start, match;
- int length;
-{
+local void check_match(deflate_state *s, IPos start, IPos match, int length) {
/* check that the match is indeed a match */
- if (zmemcmp(s->window + match,
- s->window + start, length) != EQUAL) {
- fprintf(stderr, " start %u, match %u, length %d\n",
- start, match, length);
+ Bytef *back = s->window + (int)match, *here = s->window + start;
+ IPos len = length;
+ if (match == (IPos)-1) {
+ /* match starts one byte before the current window -- just compare the
+ subsequent length-1 bytes */
+ back++;
+ here++;
+ len--;
+ }
+ if (zmemcmp(back, here, len) != EQUAL) {
+ fprintf(stderr, " start %u, match %d, length %d\n",
+ start, (int)match, length);
do {
- fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);
- } while (--length != 0);
+ fprintf(stderr, "(%02x %02x)", *back++, *here++);
+ } while (--len != 0);
z_error("invalid match");
}
if (z_verbose > 1) {
# define check_match(s, start, match, length)
#endif /* ZLIB_DEBUG */
-/* ===========================================================================
- * Fill the window when the lookahead becomes insufficient.
- * Updates strstart and lookahead.
- *
- * IN assertion: lookahead < MIN_LOOKAHEAD
- * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
- * At least one byte has been read, or avail_in == 0; reads are
- * performed for at least two bytes (required for the zip translate_eol
- * option -- not supported here).
- */
-local void fill_window(s)
- deflate_state *s;
-{
- unsigned n;
- unsigned more; /* Amount of free space at the end of the window. */
- uInt wsize = s->w_size;
-
- Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead");
-
- do {
- more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);
-
- /* Deal with !@#$% 64K limit: */
- if (sizeof(int) <= 2) {
- if (more == 0 && s->strstart == 0 && s->lookahead == 0) {
- more = wsize;
-
- } else if (more == (unsigned)(-1)) {
- /* Very unlikely, but possible on 16 bit machine if
- * strstart == 0 && lookahead == 1 (input done a byte at time)
- */
- more--;
- }
- }
-
- /* If the window is almost full and there is insufficient lookahead,
- * move the upper half to the lower one to make room in the upper half.
- */
- if (s->strstart >= wsize + MAX_DIST(s)) {
-
- zmemcpy(s->window, s->window + wsize, (unsigned)wsize - more);
- s->match_start -= wsize;
- s->strstart -= wsize; /* we now have strstart >= MAX_DIST */
- s->block_start -= (long) wsize;
- if (s->insert > s->strstart)
- s->insert = s->strstart;
- slide_hash(s);
- more += wsize;
- }
- if (s->strm->avail_in == 0) break;
-
- /* If there was no sliding:
- * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
- * more == window_size - lookahead - strstart
- * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
- * => more >= window_size - 2*WSIZE + 2
- * In the BIG_MEM or MMAP case (not yet supported),
- * window_size == input_size + MIN_LOOKAHEAD &&
- * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
- * Otherwise, window_size == 2*WSIZE so more >= 2.
- * If there was sliding, more >= WSIZE. So in all cases, more >= 2.
- */
- Assert(more >= 2, "more < 2");
-
- n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);
- s->lookahead += n;
-
- /* Initialize the hash value now that we have some input: */
- if (s->lookahead + s->insert >= MIN_MATCH) {
- uInt str = s->strstart - s->insert;
- s->ins_h = s->window[str];
- UPDATE_HASH(s, s->ins_h, s->window[str + 1]);
-#if MIN_MATCH != 3
- Call UPDATE_HASH() MIN_MATCH-3 more times
-#endif
- while (s->insert) {
- UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]);
-#ifndef FASTEST
- s->prev[str & s->w_mask] = s->head[s->ins_h];
-#endif
- s->head[s->ins_h] = (Pos)str;
- str++;
- s->insert--;
- if (s->lookahead + s->insert < MIN_MATCH)
- break;
- }
- }
- /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
- * but this is not important since only literal bytes will be emitted.
- */
-
- } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);
-
- /* If the WIN_INIT bytes after the end of the current data have never been
- * written, then zero those bytes in order to avoid memory check reports of
- * the use of uninitialized (or uninitialised as Julian writes) bytes by
- * the longest match routines. Update the high water mark for the next
- * time through here. WIN_INIT is set to MAX_MATCH since the longest match
- * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead.
- */
- if (s->high_water < s->window_size) {
- ulg curr = s->strstart + (ulg)(s->lookahead);
- ulg init;
-
- if (s->high_water < curr) {
- /* Previous high water mark below current data -- zero WIN_INIT
- * bytes or up to end of window, whichever is less.
- */
- init = s->window_size - curr;
- if (init > WIN_INIT)
- init = WIN_INIT;
- zmemzero(s->window + curr, (unsigned)init);
- s->high_water = curr + init;
- }
- else if (s->high_water < (ulg)curr + WIN_INIT) {
- /* High water mark at or above current data, but below current data
- * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up
- * to end of window, whichever is less.
- */
- init = (ulg)curr + WIN_INIT - s->high_water;
- if (init > s->window_size - s->high_water)
- init = s->window_size - s->high_water;
- zmemzero(s->window + s->high_water, (unsigned)init);
- s->high_water += init;
- }
- }
-
- Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD,
- "not enough room for search");
-}
-
/* ===========================================================================
* Flush the current block, with given end-of-file flag.
* IN assertion: strstart is set to the end of the current match.
* copied. It is most efficient with large input and output buffers, which
* maximizes the opportunities to have a single copy from next_in to next_out.
*/
-local block_state deflate_stored(s, flush)
- deflate_state *s;
- int flush;
-{
+local block_state deflate_stored(deflate_state *s, int flush) {
/* Smallest worthy block size when not flushing or finishing. By default
* this is 32K. This can be as small as 507 bytes for memLevel == 1. For
* large input and output buffers, the stored block size will be larger.
* new strings in the dictionary only for unmatched strings or for short
* matches. It is used only for the fast compression options.
*/
-local block_state deflate_fast(s, flush)
- deflate_state *s;
- int flush;
-{
+local block_state deflate_fast(deflate_state *s, int flush) {
IPos hash_head; /* head of the hash chain */
int bflush; /* set if current block must be flushed */
* evaluation for matches: a match is finally adopted only if there is
* no better match at the next window position.
*/
-local block_state deflate_slow(s, flush)
- deflate_state *s;
- int flush;
-{
+local block_state deflate_slow(deflate_state *s, int flush) {
IPos hash_head; /* head of hash chain */
int bflush; /* set if current block must be flushed */
* one. Do not maintain a hash table. (It will be regenerated if this run of
* deflate switches away from Z_RLE.)
*/
-local block_state deflate_rle(s, flush)
- deflate_state *s;
- int flush;
-{
+local block_state deflate_rle(deflate_state *s, int flush) {
int bflush; /* set if current block must be flushed */
uInt prev; /* byte at distance one to match */
Bytef *scan, *strend; /* scan goes up to strend for length of run */
* For Z_HUFFMAN_ONLY, do not look for matches. Do not maintain a hash table.
* (It will be regenerated if this run of deflate switches away from Huffman.)
*/
-local block_state deflate_huff(s, flush)
- deflate_state *s;
- int flush;
-{
+local block_state deflate_huff(deflate_state *s, int flush) {
int bflush; /* set if current block must be flushed */
for (;;) {
notaz.gp2x.de / pcsx_rearmed.git / blobdiff