Date: Sun, 18 Feb 2024 06:13:16 GMT From: Xin LI <delphij@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 6255c67c3d1a - main - MFV: zlib 1.3.1. Message-ID: <202402180613.41I6DGKL097407@gitrepo.freebsd.org>
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The branch main has been updated by delphij: URL: https://cgit.FreeBSD.org/src/commit/?id=6255c67c3d1a268535c50de74d3300fd86d8f15d commit 6255c67c3d1a268535c50de74d3300fd86d8f15d Merge: 2546c543fd79 f4695a30267c Author: Xin LI <delphij@FreeBSD.org> AuthorDate: 2024-02-18 06:12:51 +0000 Commit: Xin LI <delphij@FreeBSD.org> CommitDate: 2024-02-18 06:12:51 +0000 MFV: zlib 1.3.1. MFC after: 1 week sys/contrib/zlib/ChangeLog | 10 ++++++++ sys/contrib/zlib/FAQ | 3 +-- sys/contrib/zlib/README | 6 ++--- sys/contrib/zlib/deflate.c | 47 +++++++++++++++++++++++++++++--------- sys/contrib/zlib/deflate.h | 35 ++++++++++++++++++++++++++-- sys/contrib/zlib/doc/algorithm.txt | 2 +- sys/contrib/zlib/gzguts.h | 8 ++----- sys/contrib/zlib/gzlib.c | 12 +++++----- sys/contrib/zlib/inflate.c | 2 +- sys/contrib/zlib/inftrees.c | 6 ++--- sys/contrib/zlib/inftrees.h | 4 ++-- sys/contrib/zlib/test/example.c | 3 ++- sys/contrib/zlib/test/minigzip.c | 2 +- sys/contrib/zlib/trees.c | 20 +++++++++++++--- sys/contrib/zlib/zconf.h | 10 +------- sys/contrib/zlib/zconf.h.in | 10 +------- sys/contrib/zlib/zlib.3 | 6 ++--- sys/contrib/zlib/zlib.h | 22 +++++++++--------- sys/contrib/zlib/zutil.h | 27 +++------------------- 19 files changed, 137 insertions(+), 98 deletions(-) diff --cc sys/contrib/zlib/deflate.c index 06eb2c0f6de5,000000000000..97b184a82868 mode 100644,000000..100644 --- a/sys/contrib/zlib/deflate.c +++ b/sys/contrib/zlib/deflate.c @@@ -1,2116 -1,0 +1,2141 @@@ +/* deflate.c -- compress data using the deflation algorithm - * Copyright (C) 1995-2023 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 + */ + +/* + * ALGORITHM + * + * The "deflation" process depends on being able to identify portions + * of the input text which are identical to earlier input (within a + * sliding window trailing behind the input currently being processed). + * + * The most straightforward technique turns out to be the fastest for + * most input files: try all possible matches and select the longest. + * The key feature of this algorithm is that insertions into the string + * dictionary are very simple and thus fast, and deletions are avoided + * completely. Insertions are performed at each input character, whereas + * string matches are performed only when the previous match ends. So it + * is preferable to spend more time in matches to allow very fast string + * insertions and avoid deletions. The matching algorithm for small + * strings is inspired from that of Rabin & Karp. A brute force approach + * is used to find longer strings when a small match has been found. + * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze + * (by Leonid Broukhis). + * A previous version of this file used a more sophisticated algorithm + * (by Fiala and Greene) which is guaranteed to run in linear amortized + * time, but has a larger average cost, uses more memory and is patented. + * However the F&G algorithm may be faster for some highly redundant + * files if the parameter max_chain_length (described below) is too large. + * + * ACKNOWLEDGEMENTS + * + * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and + * I found it in 'freeze' written by Leonid Broukhis. + * Thanks to many people for bug reports and testing. + * + * REFERENCES + * + * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification". + * Available in http://tools.ietf.org/html/rfc1951 + * + * A description of the Rabin and Karp algorithm is given in the book + * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. + * + * Fiala,E.R., and Greene,D.H. + * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 + * + */ + +/* @(#) $Id$ */ + +#include "deflate.h" + +const char deflate_copyright[] = - " deflate 1.3 Copyright 1995-2023 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 + include such an acknowledgment, I would appreciate that you keep this + copyright string in the executable of your product. + */ + +typedef enum { + need_more, /* block not completed, need more input or more output */ + block_done, /* block flush performed */ + finish_started, /* finish started, need only more output at next deflate */ + finish_done /* finish done, accept no more input or output */ +} block_state; + +typedef block_state (*compress_func)(deflate_state *s, int flush); +/* Compression function. Returns the block state after the call. */ + +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(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 + */ + +#define NIL 0 +/* Tail of hash chains */ + +#ifndef TOO_FAR +# define TOO_FAR 4096 +#endif +/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ + +/* Values for max_lazy_match, good_match and max_chain_length, depending on + * the desired pack level (0..9). The values given below have been tuned to + * exclude worst case performance for pathological files. Better values may be + * found for specific files. + */ +typedef struct config_s { + ush good_length; /* reduce lazy search above this match length */ + ush max_lazy; /* do not perform lazy search above this match length */ + ush nice_length; /* quit search above this match length */ + ush max_chain; + compress_func func; +} config; + +#ifdef FASTEST +local const config configuration_table[2] = { +/* good lazy nice chain */ +/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ +/* 1 */ {4, 4, 8, 4, deflate_fast}}; /* max speed, no lazy matches */ +#else +local const config configuration_table[10] = { +/* good lazy nice chain */ +/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ +/* 1 */ {4, 4, 8, 4, deflate_fast}, /* max speed, no lazy matches */ +/* 2 */ {4, 5, 16, 8, deflate_fast}, +/* 3 */ {4, 6, 32, 32, deflate_fast}, + +/* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */ +/* 5 */ {8, 16, 32, 32, deflate_slow}, +/* 6 */ {8, 16, 128, 128, deflate_slow}, +/* 7 */ {8, 32, 128, 256, deflate_slow}, +/* 8 */ {32, 128, 258, 1024, deflate_slow}, +/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* max compression */ +#endif + +/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 + * For deflate_fast() (levels <= 3) good is ignored and lazy has a different + * meaning. + */ + +/* rank Z_BLOCK between Z_NO_FLUSH and Z_PARTIAL_FLUSH */ +#define RANK(f) (((f) * 2) - ((f) > 4 ? 9 : 0)) + +/* =========================================================================== + * Update a hash value with the given input byte + * IN assertion: all calls to UPDATE_HASH are made with consecutive input + * characters, so that a running hash key can be computed from the previous + * key instead of complete recalculation each time. + */ +#define UPDATE_HASH(s,h,c) (h = (((h) << s->hash_shift) ^ (c)) & s->hash_mask) + + +/* =========================================================================== + * Insert string str in the dictionary and set match_head to the previous head + * of the hash chain (the most recent string with same hash key). Return + * the previous length of the hash chain. + * If this file is compiled with -DFASTEST, the compression level is forced + * to 1, and no hash chains are maintained. + * IN assertion: all calls to INSERT_STRING are made with consecutive input + * characters and the first MIN_MATCH bytes of str are valid (except for + * the last MIN_MATCH-1 bytes of the input file). + */ +#ifdef FASTEST +#define INSERT_STRING(s, str, match_head) \ + (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ + match_head = s->head[s->ins_h], \ + s->head[s->ins_h] = (Pos)(str)) +#else +#define INSERT_STRING(s, str, match_head) \ + (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ + match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \ + s->head[s->ins_h] = (Pos)(str)) +#endif + +/* =========================================================================== + * Initialize the hash table (avoiding 64K overflow for 16 bit systems). + * prev[] will be initialized on the fly. + */ +#define CLEAR_HASH(s) \ + do { \ + s->head[s->hash_size - 1] = NIL; \ + zmemzero((Bytef *)s->head, \ + (unsigned)(s->hash_size - 1)*sizeof(*s->head)); \ + } while (0) + +/* =========================================================================== + * Slide the hash table when sliding the window down (could be avoided with 32 + * 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. + */ +#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; + + n = s->hash_size; + p = &s->head[n]; + do { + m = *--p; + *p = (Pos)(m >= wsize ? m - wsize : NIL); + } while (--n); + n = wsize; +#ifndef FASTEST + p = &s->prev[n]; + do { + m = *--p; + *p = (Pos)(m >= wsize ? m - wsize : NIL); + /* If n is not on any hash chain, prev[n] is garbage but + * its value will never be used. + */ + } while (--n); +#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_(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_(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; + + if (version == Z_NULL || version[0] != my_version[0] || + stream_size != sizeof(z_stream)) { + return Z_VERSION_ERROR; + } + if (strm == Z_NULL) return Z_STREAM_ERROR; + + strm->msg = Z_NULL; + if (strm->zalloc == (alloc_func)0) { +#if defined(Z_SOLO) && !defined(_KERNEL) + return Z_STREAM_ERROR; +#else + strm->zalloc = zcalloc; + strm->opaque = (voidpf)0; +#endif + } + if (strm->zfree == (free_func)0) +#if defined(Z_SOLO) && !defined(_KERNEL) + return Z_STREAM_ERROR; +#else + strm->zfree = zcfree; +#endif + +#ifdef FASTEST + if (level != 0) level = 1; +#else + if (level == Z_DEFAULT_COMPRESSION) level = 6; +#endif + + if (windowBits < 0) { /* suppress zlib wrapper */ + wrap = 0; + if (windowBits < -15) + return Z_STREAM_ERROR; + windowBits = -windowBits; + } +#ifdef GZIP + else if (windowBits > 15) { + wrap = 2; /* write gzip wrapper instead */ + windowBits -= 16; + } +#endif + if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED || + windowBits < 8 || windowBits > 15 || level < 0 || level > 9 || + strategy < 0 || strategy > Z_FIXED || (windowBits == 8 && wrap != 1)) { + return Z_STREAM_ERROR; + } + if (windowBits == 8) windowBits = 9; /* until 256-byte window bug fixed */ + s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state)); + if (s == Z_NULL) return Z_MEM_ERROR; + strm->state = (struct internal_state FAR *)s; + s->strm = strm; + s->status = INIT_STATE; /* to pass state test in deflateReset() */ + + s->wrap = wrap; + s->gzhead = Z_NULL; + s->w_bits = (uInt)windowBits; + s->w_size = 1 << s->w_bits; + s->w_mask = s->w_size - 1; + + s->hash_bits = (uInt)memLevel + 7; + s->hash_size = 1 << s->hash_bits; + s->hash_mask = s->hash_size - 1; + s->hash_shift = ((s->hash_bits + MIN_MATCH-1) / MIN_MATCH); + + s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte)); + s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); + s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); + + s->high_water = 0; /* nothing written to s->window yet */ + + s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ + + /* We overlay pending_buf and sym_buf. This works since the average size + * for length/distance pairs over any compressed block is assured to be 31 + * bits or less. + * + * Analysis: The longest fixed codes are a length code of 8 bits plus 5 + * extra bits, for lengths 131 to 257. The longest fixed distance codes are + * 5 bits plus 13 extra bits, for distances 16385 to 32768. The longest + * possible fixed-codes length/distance pair is then 31 bits total. + * + * sym_buf starts one-fourth of the way into pending_buf. So there are + * three bytes in sym_buf for every four bytes in pending_buf. Each symbol + * in sym_buf is three bytes -- two for the distance and one for the + * literal/length. As each symbol is consumed, the pointer to the next + * sym_buf value to read moves forward three bytes. From that symbol, up to + * 31 bits are written to pending_buf. The closest the written pending_buf + * bits gets to the next sym_buf symbol to read is just before the last + * code is written. At that time, 31*(n - 2) bits have been written, just + * after 24*(n - 2) bits have been consumed from sym_buf. sym_buf starts at + * 8*n bits into pending_buf. (Note that the symbol buffer fills when n - 1 + * symbols are written.) The closest the writing gets to what is unread is + * then n + 14 bits. Here n is lit_bufsize, which is 16384 by default, and + * can range from 128 to 32768. + * + * Therefore, at a minimum, there are 142 bits of space between what is + * written and what is read in the overlain buffers, so the symbols cannot + * be overwritten by the compressed data. That space is actually 139 bits, + * due to the three-bit fixed-code block header. + * + * That covers the case where either Z_FIXED is specified, forcing fixed + * codes, or when the use of fixed codes is chosen, because that choice + * results in a smaller compressed block than dynamic codes. That latter + * condition then assures that the above analysis also covers all dynamic + * blocks. A dynamic-code block will only be chosen to be emitted if it has + * fewer bits than a fixed-code block would for the same set of symbols. + * Therefore its average symbol length is assured to be less than 31. So + * the compressed data for a dynamic block also cannot overwrite the + * 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 || + s->pending_buf == Z_NULL) { + s->status = FINISH_STATE; + strm->msg = ERR_MSG(Z_MEM_ERROR); + 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. + */ + + s->level = level; + s->strategy = strategy; + s->method = (Byte)method; + + return deflateReset(strm); +} + +/* ========================================================================= + * Check for a valid deflate stream state. Return 0 if ok, 1 if not. + */ +local int deflateStateCheck(z_streamp strm) { + deflate_state *s; + if (strm == Z_NULL || + strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) + return 1; + s = strm->state; + if (s == Z_NULL || s->strm != strm || (s->status != INIT_STATE && +#ifdef GZIP + s->status != GZIP_STATE && +#endif + s->status != EXTRA_STATE && + s->status != NAME_STATE && + s->status != COMMENT_STATE && + s->status != HCRC_STATE && + s->status != BUSY_STATE && + s->status != FINISH_STATE)) + return 1; + return 0; +} + +/* ========================================================================= */ +int ZEXPORT deflateSetDictionary(z_streamp strm, const Bytef *dictionary, + uInt dictLength) { + deflate_state *s; + uInt str, n; + int wrap; + unsigned avail; + z_const unsigned char *next; + + if (deflateStateCheck(strm) || dictionary == Z_NULL) + return Z_STREAM_ERROR; + s = strm->state; + wrap = s->wrap; + if (wrap == 2 || (wrap == 1 && s->status != INIT_STATE) || s->lookahead) + return Z_STREAM_ERROR; + + /* when using zlib wrappers, compute Adler-32 for provided dictionary */ + if (wrap == 1) + strm->adler = adler32(strm->adler, dictionary, dictLength); + s->wrap = 0; /* avoid computing Adler-32 in read_buf */ + + /* if dictionary would fill window, just replace the history */ + if (dictLength >= s->w_size) { + if (wrap == 0) { /* already empty otherwise */ + CLEAR_HASH(s); + s->strstart = 0; + s->block_start = 0L; + s->insert = 0; + } + dictionary += dictLength - s->w_size; /* use the tail */ + dictLength = s->w_size; + } + + /* insert dictionary into window and hash */ + avail = strm->avail_in; + next = strm->next_in; + strm->avail_in = dictLength; + strm->next_in = (z_const Bytef *)dictionary; + fill_window(s); + while (s->lookahead >= MIN_MATCH) { + str = s->strstart; + n = s->lookahead - (MIN_MATCH-1); + do { + 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++; + } while (--n); + s->strstart = str; + s->lookahead = MIN_MATCH-1; + fill_window(s); + } + s->strstart += s->lookahead; + s->block_start = (long)s->strstart; + s->insert = s->lookahead; + s->lookahead = 0; + s->match_length = s->prev_length = MIN_MATCH-1; + s->match_available = 0; + strm->next_in = next; + strm->avail_in = avail; + s->wrap = wrap; + return Z_OK; +} + +/* ========================================================================= */ +int ZEXPORT deflateGetDictionary(z_streamp strm, Bytef *dictionary, + uInt *dictLength) { + deflate_state *s; + uInt len; + + if (deflateStateCheck(strm)) + return Z_STREAM_ERROR; + s = strm->state; + len = s->strstart + s->lookahead; + if (len > s->w_size) + len = s->w_size; + if (dictionary != Z_NULL && len) + zmemcpy(dictionary, s->window + s->strstart + s->lookahead - len, len); + if (dictLength != Z_NULL) + *dictLength = len; + return Z_OK; +} + +/* ========================================================================= */ +int ZEXPORT deflateResetKeep(z_streamp strm) { + deflate_state *s; + + if (deflateStateCheck(strm)) { + return Z_STREAM_ERROR; + } + + strm->total_in = strm->total_out = 0; + strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ + strm->data_type = Z_UNKNOWN; + + s = (deflate_state *)strm->state; + s->pending = 0; + s->pending_out = s->pending_buf; + + if (s->wrap < 0) { + s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */ + } + s->status = +#ifdef GZIP + s->wrap == 2 ? GZIP_STATE : +#endif + INIT_STATE; + strm->adler = +#ifdef GZIP + s->wrap == 2 ? crc32(0L, Z_NULL, 0) : +#endif + adler32(0L, Z_NULL, 0); + s->last_flush = -2; + + _tr_init(s); + + 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(z_streamp strm) { + int ret; + + ret = deflateResetKeep(strm); + if (ret == Z_OK) + lm_init(strm->state); + return ret; +} + +/* ========================================================================= */ +int ZEXPORT deflateSetHeader(z_streamp strm, gz_headerp head) { + if (deflateStateCheck(strm) || strm->state->wrap != 2) + return Z_STREAM_ERROR; + strm->state->gzhead = head; + return Z_OK; +} + +/* ========================================================================= */ +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; + if (bits != Z_NULL) + *bits = strm->state->bi_valid; + return Z_OK; +} + +/* ========================================================================= */ +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) + put = bits; + s->bi_buf |= (ush)((value & ((1 << put) - 1)) << s->bi_valid); + s->bi_valid += put; + _tr_flush_bits(s); + value >>= put; + bits -= put; + } while (bits); + return Z_OK; +} + +/* ========================================================================= */ +int ZEXPORT deflateParams(z_streamp strm, int level, int strategy) { + deflate_state *s; + compress_func func; + + if (deflateStateCheck(strm)) return Z_STREAM_ERROR; + s = strm->state; + +#ifdef FASTEST + if (level != 0) level = 1; +#else + if (level == Z_DEFAULT_COMPRESSION) level = 6; +#endif + if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) { + return Z_STREAM_ERROR; + } + func = configuration_table[s->level].func; + + if ((strategy != s->strategy || func != configuration_table[level].func) && + s->last_flush != -2) { + /* Flush the last buffer: */ + int err = deflate(strm, Z_BLOCK); + if (err == Z_STREAM_ERROR) + return err; + if (strm->avail_in || (s->strstart - s->block_start) + s->lookahead) + return Z_BUF_ERROR; + } + if (s->level != level) { + if (s->level == 0 && s->matches != 0) { + if (s->matches == 1) + slide_hash(s); + else + CLEAR_HASH(s); + s->matches = 0; + } + s->level = level; + s->max_lazy_match = configuration_table[level].max_lazy; + s->good_match = configuration_table[level].good_length; + s->nice_match = configuration_table[level].nice_length; + s->max_chain_length = configuration_table[level].max_chain; + } + s->strategy = strategy; + return Z_OK; +} + +/* ========================================================================= */ +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; + s = strm->state; + s->good_match = (uInt)good_length; + s->max_lazy_match = (uInt)max_lazy; + s->nice_match = nice_length; + s->max_chain_length = (uInt)max_chain; + return Z_OK; +} + +/* ========================================================================= + * For the default windowBits of 15 and memLevel of 8, this function returns a + * close to exact, as well as small, upper bound on the compressed size. This + * is an expansion of ~0.03%, plus a small constant. + * + * For any setting other than those defaults for windowBits and memLevel, one + * of two worst case bounds is returned. This is at most an expansion of ~4% or + * ~13%, plus a small constant. + * + * Both the 0.03% and 4% derive from the overhead of stored blocks. The first + * one is for stored blocks of 16383 bytes (memLevel == 8), whereas the second + * is for stored blocks of 127 bytes (the worst case memLevel == 1). The + * expansion results from five bytes of header for each stored block. + * + * The larger expansion of 13% results from a window size less than or equal to + * the symbols buffer size (windowBits <= memLevel + 7). In that case some of + * the data being compressed may have slid out of the sliding window, impeding + * a stored block from being emitted. Then the only choice is a fixed or + * dynamic block, where a fixed block limits the maximum expansion to 9 bits + * per 8-bit byte, plus 10 bits for every block. The smallest block size for + * which this can occur is 255 (memLevel == 2). + * + * Shifts are used to approximate divisions, for speed. + */ +uLong ZEXPORT deflateBound(z_streamp strm, uLong sourceLen) { + deflate_state *s; + uLong fixedlen, storelen, wraplen; + + /* upper bound for fixed blocks with 9-bit literals and length 255 + (memLevel == 2, which is the lowest that may not use stored blocks) -- + ~13% overhead plus a small constant */ + fixedlen = sourceLen + (sourceLen >> 3) + (sourceLen >> 8) + + (sourceLen >> 9) + 4; + + /* upper bound for stored blocks with length 127 (memLevel == 1) -- + ~4% overhead plus a small constant */ + storelen = sourceLen + (sourceLen >> 5) + (sourceLen >> 7) + + (sourceLen >> 11) + 7; + + /* if can't get parameters, return larger bound plus a zlib wrapper */ + if (deflateStateCheck(strm)) + return (fixedlen > storelen ? fixedlen : storelen) + 6; + + /* compute wrapper length */ + s = strm->state; + switch (s->wrap) { + case 0: /* raw deflate */ + wraplen = 0; + break; + case 1: /* zlib wrapper */ + wraplen = 6 + (s->strstart ? 4 : 0); + break; +#ifdef GZIP + case 2: /* gzip wrapper */ + wraplen = 18; + if (s->gzhead != Z_NULL) { /* user-supplied gzip header */ + Bytef *str; + if (s->gzhead->extra != Z_NULL) + wraplen += 2 + s->gzhead->extra_len; + str = s->gzhead->name; + if (str != Z_NULL) + do { + wraplen++; + } while (*str++); + str = s->gzhead->comment; + if (str != Z_NULL) + do { + wraplen++; + } while (*str++); + if (s->gzhead->hcrc) + wraplen += 2; + } + break; +#endif + default: /* for compiler happiness */ + wraplen = 6; + } + + /* 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 && s->level ? fixedlen : storelen) + + wraplen; + + /* default settings: return tight bound for that case -- ~0.03% overhead + plus a small constant */ + return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + + (sourceLen >> 25) + 13 - 6 + wraplen; +} + +/* ========================================================================= + * Put a short in the pending buffer. The 16-bit value is put in MSB order. + * IN assertion: the stream state is correct and there is enough room in + * pending_buf. + */ +local void putShortMSB(deflate_state *s, uInt b) { + put_byte(s, (Byte)(b >> 8)); + put_byte(s, (Byte)(b & 0xff)); +} + +/* ========================================================================= + * Flush as much pending output as possible. All deflate() output, except for + * some deflate_stored() output, goes through this function so some + * 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(z_streamp strm) { + unsigned len; + deflate_state *s = strm->state; + + _tr_flush_bits(s); + len = s->pending; + if (len > strm->avail_out) len = strm->avail_out; + if (len == 0) return; + + zmemcpy(strm->next_out, s->pending_out, len); + strm->next_out += len; + s->pending_out += len; + strm->total_out += len; + strm->avail_out -= len; + s->pending -= len; + if (s->pending == 0) { + s->pending_out = s->pending_buf; + } +} + +/* =========================================================================== + * Update the header CRC with the bytes s->pending_buf[beg..s->pending - 1]. + */ +#define HCRC_UPDATE(beg) \ + do { \ + if (s->gzhead->hcrc && s->pending > (beg)) \ + strm->adler = crc32(strm->adler, s->pending_buf + (beg), \ + s->pending - (beg)); \ *** 3763 LINES SKIPPED ***
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