Date: Fri, 13 Mar 2026 23:50:32 +0000 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: 7aa1dba6b00c - main - MFV: zlib 1.3.2. Message-ID: <69b4a2c8.23dd9.9e7d214@gitrepo.freebsd.org>
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The branch main has been updated by delphij: URL: https://cgit.FreeBSD.org/src/commit/?id=7aa1dba6b00ccfb7d66627badc8a7aaa06b02946 commit 7aa1dba6b00ccfb7d66627badc8a7aaa06b02946 Merge: eb0a78f6cef0 280d433d4c13 Author: Xin LI <delphij@FreeBSD.org> AuthorDate: 2026-03-13 23:49:53 +0000 Commit: Xin LI <delphij@FreeBSD.org> CommitDate: 2026-03-13 23:49:53 +0000 MFV: zlib 1.3.2. Relnotes: yes MFC after: 2 weeks lib/libz/Symbol.map | 13 + lib/libz/Versions.def | 6 + sys/contrib/zlib/ChangeLog | 51 +++ sys/contrib/zlib/FAQ | 46 +- sys/contrib/zlib/LICENSE | 2 +- sys/contrib/zlib/README | 28 +- sys/contrib/zlib/compress.c | 44 +- sys/contrib/zlib/contrib/README.contrib | 57 --- sys/contrib/zlib/contrib/gcc_gvmat64/gvmat64.S | 574 ------------------------- sys/contrib/zlib/crc32.c | 164 +++---- sys/contrib/zlib/deflate.c | 176 +++++--- sys/contrib/zlib/deflate.h | 8 +- sys/contrib/zlib/doc/algorithm.txt | 2 +- sys/contrib/zlib/gzguts.h | 64 +-- sys/contrib/zlib/gzlib.c | 103 +++-- sys/contrib/zlib/gzread.c | 296 ++++++++----- sys/contrib/zlib/gzwrite.c | 267 +++++++----- sys/contrib/zlib/infback.c | 87 +--- sys/contrib/zlib/inffast.c | 13 +- sys/contrib/zlib/inffixed.h | 182 ++++---- sys/contrib/zlib/inflate.c | 189 ++------ sys/contrib/zlib/inflate.h | 2 +- sys/contrib/zlib/inftrees.c | 143 +++++- sys/contrib/zlib/inftrees.h | 4 +- sys/contrib/zlib/test/example.c | 14 +- sys/contrib/zlib/test/infcover.c | 10 +- sys/contrib/zlib/test/minigzip.c | 89 ++-- sys/contrib/zlib/trees.c | 28 +- sys/contrib/zlib/uncompr.c | 62 ++- sys/contrib/zlib/zconf.h | 54 ++- sys/contrib/zlib/zconf.h.in | 46 +- sys/contrib/zlib/zlib.3 | 22 +- sys/contrib/zlib/zlib.h | 309 +++++++++---- sys/contrib/zlib/zlib.map | 16 + sys/contrib/zlib/zlib.pc.in | 1 + sys/contrib/zlib/zutil.c | 84 ++-- sys/contrib/zlib/zutil.h | 99 ++++- 37 files changed, 1613 insertions(+), 1742 deletions(-) diff --cc lib/libz/Symbol.map index 7bfe7cceda77,000000000000..5df1d5253f91 mode 100644,000000..100644 --- a/lib/libz/Symbol.map +++ b/lib/libz/Symbol.map @@@ -1,114 -1,0 +1,127 @@@ +/* + */ + +ZLIB_1.2.12 { + crc32_combine_gen; + crc32_combine_gen64; + crc32_combine_op; +}; + ++ZLIB_1.3.1.2 { ++ deflateUsed; ++}; ++ ++ZLIB_1.3.2 { ++ compressBound_z; ++ compress_z; ++ compress2_z; ++ deflateBound_z; ++ uncompress_z; ++ uncompress2_z; ++}; ++ +ZLIB_1.2.9 { + inflateCodesUsed; + inflateValidate; + uncompress2; + gzfread; + gzfwrite; + deflateGetDictionary; + adler32_z; + crc32_z; +}; + +ZLIB_1.2.7.1 { + inflateGetDictionary; + gzvprintf; +}; + +ZLIB_1.2.7.0 { + deflatePending; + deflateResetKeep; + gzgetc_; + inflateResetKeep; +}; + +ZLIB_1.2.4.0 { + adler32; + adler32_combine; + adler32_combine64; + compress; + compress2; + compressBound; + crc32; + crc32_combine; + crc32_combine64; + deflate; + deflateBound; + deflateCopy; + deflateEnd; + deflateInit2_; + deflateInit_; + deflateParams; + deflatePrime; + deflateReset; + deflateSetDictionary; + deflateSetHeader; + deflateTune; + get_crc_table; + gzbuffer; + gzclearerr; + gzclose; + gzclose_r; + gzclose_w; + gzdirect; + gzdopen; + gzeof; + gzerror; + gzflush; + gzgetc; + gzgets; + gzoffset; + gzoffset64; + gzopen; + gzopen64; + gzprintf; + gzputc; + gzputs; + gzread; + gzrewind; + gzseek; + gzseek64; + gzsetparams; + gztell; + gztell64; + gzungetc; + gzwrite; + inflate; + inflateBack; + inflateBackEnd; + inflateBackInit_; + inflateCopy; + inflateEnd; + inflateGetHeader; + inflateInit2_; + inflateInit_; + inflateMark; + inflatePrime; + inflateReset; + inflateReset2; + inflateSetDictionary; + inflateSync; + inflateSyncPoint; + inflateUndermine; + uncompress; + zError; + zlibCompileFlags; + zlibVersion; +}; + +FBSD_1.2 { + zopen; +}; + +FBSD_1.6 { + zdopen; +}; + diff --cc lib/libz/Versions.def index 2ee0106b5bfe,000000000000..73b197240a4c mode 100644,000000..100644 --- a/lib/libz/Versions.def +++ b/lib/libz/Versions.def @@@ -1,22 -1,0 +1,28 @@@ + +ZLIB_1.2.4.0 { +}; + +ZLIB_1.2.7.0 { +} ZLIB_1.2.4.0; + +ZLIB_1.2.7.1 { +} ZLIB_1.2.7.0; + +ZLIB_1.2.9 { +} ZLIB_1.2.7.1; + +ZLIB_1.2.12 { +} ZLIB_1.2.9; + ++ZLIB_1.3.1.2 { ++} ZLIB_1.2.12; ++ ++ZLIB_1.3.2 { ++} ZLIB_1.3.1.2; ++ +FBSD_1.2 { +} ZLIB_1.2.4.0; + +FBSD_1.6 { +} FBSD_1.2; + diff --cc sys/contrib/zlib/deflate.c index 97b184a82868,000000000000..e782ad519721 mode 100644,000000..100644 --- a/sys/contrib/zlib/deflate.c +++ b/sys/contrib/zlib/deflate.c @@@ -1,2141 -1,0 +1,2187 @@@ +/* deflate.c -- compress data using the deflation algorithm - * Copyright (C) 1995-2024 Jean-loup Gailly and Mark Adler ++ * Copyright (C) 1995-2026 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 ++ * Available at https://datatracker.ietf.org/doc/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 1.3.1 Copyright 1995-2024 Jean-loup Gailly and Mark Adler "; ++ " deflate 1.3.2 Copyright 1995-2026 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)); \ ++ zmemzero(s->head, (unsigned)(s->hash_size - 1)*sizeof(*s->head)); \ ++ s->slid = 0; \ + } 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 ++ n = wsize; + 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 ++ s->slid = 1; +} + +/* =========================================================================== + * 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: */ ++#ifdef _MSC_VER ++#pragma warning(push) ++#pragma warning(disable: 4127) ++#endif + if (sizeof(int) <= 2) { ++#ifdef _MSC_VER ++#pragma warning(pop) ++#endif + 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; ++ zmemzero(s, sizeof(deflate_state)); + 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, 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; ++ if (pending != Z_NULL) { ++ *pending = (unsigned)strm->state->pending; ++ if (*pending != strm->state->pending) { ++ *pending = (unsigned)-1; ++ return Z_BUF_ERROR; ++ } ++ } ++ return Z_OK; ++} ++ ++/* ========================================================================= */ ++int ZEXPORT deflateUsed(z_streamp strm, int *bits) { ++ if (deflateStateCheck(strm)) return Z_STREAM_ERROR; ++ if (bits != Z_NULL) ++ *bits = strm->state->bi_used; + 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 *** 6398 LINES SKIPPED ***home | help
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