1ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* deflate.c -- compress data using the deflation algorithm 2ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler 3ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * For conditions of distribution and use, see copyright notice in zlib.h 4ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 5ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 6ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 7ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * ALGORITHM 8ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 9ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * The "deflation" process depends on being able to identify portions 10ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * of the input text which are identical to earlier input (within a 11ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * sliding window trailing behind the input currently being processed). 12ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 13ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * The most straightforward technique turns out to be the fastest for 14ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * most input files: try all possible matches and select the longest. 15ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * The key feature of this algorithm is that insertions into the string 16ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * dictionary are very simple and thus fast, and deletions are avoided 17ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * completely. Insertions are performed at each input character, whereas 18ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * string matches are performed only when the previous match ends. So it 19ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * is preferable to spend more time in matches to allow very fast string 20ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * insertions and avoid deletions. The matching algorithm for small 21ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * strings is inspired from that of Rabin & Karp. A brute force approach 22ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * is used to find longer strings when a small match has been found. 23ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * A similar algorithm is used in comic (by Jan-Mark Wams) and freeze 24ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * (by Leonid Broukhis). 25ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * A previous version of this file used a more sophisticated algorithm 26ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * (by Fiala and Greene) which is guaranteed to run in linear amortized 27ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * time, but has a larger average cost, uses more memory and is patented. 28ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * However the F&G algorithm may be faster for some highly redundant 29ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * files if the parameter max_chain_length (described below) is too large. 30ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 31ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * ACKNOWLEDGEMENTS 32ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 33ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * The idea of lazy evaluation of matches is due to Jan-Mark Wams, and 34ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * I found it in 'freeze' written by Leonid Broukhis. 35ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Thanks to many people for bug reports and testing. 36ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 37ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * REFERENCES 38ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 39ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification". 40ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Available in http://tools.ietf.org/html/rfc1951 41ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 42ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * A description of the Rabin and Karp algorithm is given in the book 43ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. 44ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 45ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Fiala,E.R., and Greene,D.H. 46ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595 47ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 48ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 49ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 50ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* @(#) $Id$ */ 51ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 52ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#include "deflate.h" 53ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 54ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovconst char deflate_copyright[] = 55ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov " deflate 1.2.8 Copyright 1995-2013 Jean-loup Gailly and Mark Adler "; 56ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 57ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov If you use the zlib library in a product, an acknowledgment is welcome 58ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov in the documentation of your product. If for some reason you cannot 59ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov include such an acknowledgment, I would appreciate that you keep this 60ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov copyright string in the executable of your product. 61ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 62ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 63ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 64ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Function prototypes. 65ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 66ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovtypedef enum { 67ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov need_more, /* block not completed, need more input or more output */ 68ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov block_done, /* block flush performed */ 69ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov finish_started, /* finish started, need only more output at next deflate */ 70ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov finish_done /* finish done, accept no more input or output */ 71ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} block_state; 72ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 73ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovtypedef block_state (*compress_func) OF((deflate_state *s, int flush)); 74ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* Compression function. Returns the block state after the call. */ 75ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 76ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void fill_window OF((deflate_state *s)); 77ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_stored OF((deflate_state *s, int flush)); 78ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_fast OF((deflate_state *s, int flush)); 79ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 80ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_slow OF((deflate_state *s, int flush)); 81ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 82ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_rle OF((deflate_state *s, int flush)); 83ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_huff OF((deflate_state *s, int flush)); 84ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void lm_init OF((deflate_state *s)); 85ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void putShortMSB OF((deflate_state *s, uInt b)); 86ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void flush_pending OF((z_streamp strm)); 87ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal int read_buf OF((z_streamp strm, Bytef *buf, unsigned size)); 88ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef ASMV 89ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov void match_init OF((void)); /* asm code initialization */ 90ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt longest_match OF((deflate_state *s, IPos cur_match)); 91ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 92ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal uInt longest_match OF((deflate_state *s, IPos cur_match)); 93ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 94ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 95ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef DEBUG 96ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void check_match OF((deflate_state *s, IPos start, IPos match, 97ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int length)); 98ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 99ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 100ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 101ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Local data 102ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 103ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 104ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define NIL 0 105ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* Tail of hash chains */ 106ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 107ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef TOO_FAR 108ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov# define TOO_FAR 4096 109ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 110ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */ 111ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 112ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* Values for max_lazy_match, good_match and max_chain_length, depending on 113ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the desired pack level (0..9). The values given below have been tuned to 114ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * exclude worst case performance for pathological files. Better values may be 115ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * found for specific files. 116ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 117ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovtypedef struct config_s { 118ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ush good_length; /* reduce lazy search above this match length */ 119ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ush max_lazy; /* do not perform lazy search above this match length */ 120ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ush nice_length; /* quit search above this match length */ 121ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ush max_chain; 122ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov compress_func func; 123ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} config; 124ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 125ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef FASTEST 126ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal const config configuration_table[2] = { 127ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* good lazy nice chain */ 128ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ 129ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 1 */ {4, 4, 8, 4, deflate_fast}}; /* max speed, no lazy matches */ 130ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 131ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal const config configuration_table[10] = { 132ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* good lazy nice chain */ 133ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 0 */ {0, 0, 0, 0, deflate_stored}, /* store only */ 134ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 1 */ {4, 4, 8, 4, deflate_fast}, /* max speed, no lazy matches */ 135ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 2 */ {4, 5, 16, 8, deflate_fast}, 136ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 3 */ {4, 6, 32, 32, deflate_fast}, 137ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 138ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 4 */ {4, 4, 16, 16, deflate_slow}, /* lazy matches */ 139ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 5 */ {8, 16, 32, 32, deflate_slow}, 140ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 6 */ {8, 16, 128, 128, deflate_slow}, 141ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 7 */ {8, 32, 128, 256, deflate_slow}, 142ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 8 */ {32, 128, 258, 1024, deflate_slow}, 143ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* 9 */ {32, 258, 258, 4096, deflate_slow}}; /* max compression */ 144ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 145ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 146ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4 147ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * For deflate_fast() (levels <= 3) good is ignored and lazy has a different 148ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * meaning. 149ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 150ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 151ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define EQUAL 0 152ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* result of memcmp for equal strings */ 153ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 154ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef NO_DUMMY_DECL 155ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovstruct static_tree_desc_s {int dummy;}; /* for buggy compilers */ 156ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 157ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 158ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* rank Z_BLOCK between Z_NO_FLUSH and Z_PARTIAL_FLUSH */ 159ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define RANK(f) (((f) << 1) - ((f) > 4 ? 9 : 0)) 160ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 161ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 162ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Update a hash value with the given input byte 163ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * IN assertion: all calls to to UPDATE_HASH are made with consecutive 164ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * input characters, so that a running hash key can be computed from the 165ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * previous key instead of complete recalculation each time. 166ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 167ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask) 168ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 169ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 170ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 171ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Insert string str in the dictionary and set match_head to the previous head 172ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * of the hash chain (the most recent string with same hash key). Return 173ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the previous length of the hash chain. 174ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * If this file is compiled with -DFASTEST, the compression level is forced 175ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * to 1, and no hash chains are maintained. 176ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * IN assertion: all calls to to INSERT_STRING are made with consecutive 177ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * input characters and the first MIN_MATCH bytes of str are valid 178ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * (except for the last MIN_MATCH-1 bytes of the input file). 179ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 180ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef FASTEST 181ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define INSERT_STRING(s, str, match_head) \ 182ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ 183ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov match_head = s->head[s->ins_h], \ 184ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->head[s->ins_h] = (Pos)(str)) 185ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 186ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define INSERT_STRING(s, str, match_head) \ 187ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \ 188ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \ 189ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->head[s->ins_h] = (Pos)(str)) 190ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 191ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 192ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 193ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Initialize the hash table (avoiding 64K overflow for 16 bit systems). 194ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * prev[] will be initialized on the fly. 195ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 196ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define CLEAR_HASH(s) \ 197ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->head[s->hash_size-1] = NIL; \ 198ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head)); 199ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 200ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 201ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateInit_( 202ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 203ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int level, 204ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov const char *version, 205ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int stream_size) 206ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 207ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL, 208ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Z_DEFAULT_STRATEGY, version, stream_size); 209ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* To do: ignore strm->next_in if we use it as window */ 210ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 211ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 212ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 213ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateInit2_( 214ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 215ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int level, 216ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int method, 217ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int windowBits, 218ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int memLevel, 219ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int strategy, 220ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov const char *version, 221ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int stream_size) 222ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 223ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 224ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int wrap = 1; 225ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov static const char my_version[] = ZLIB_VERSION; 226ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 227ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ushf *overlay; 228ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* We overlay pending_buf and d_buf+l_buf. This works since the average 229ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * output size for (length,distance) codes is <= 24 bits. 230ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 231ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 232ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (version == Z_NULL || version[0] != my_version[0] || 233ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov stream_size != sizeof(z_stream)) { 234ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_VERSION_ERROR; 235ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 236ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL) return Z_STREAM_ERROR; 237ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 238ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->msg = Z_NULL; 239ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->zalloc == (alloc_func)0) { 240ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef Z_SOLO 241ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 242ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 243ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->zalloc = zcalloc; 244ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->opaque = (voidpf)0; 245ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 246ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 247ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->zfree == (free_func)0) 248ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef Z_SOLO 249ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 250ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 251ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->zfree = zcfree; 252ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 253ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 254ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef FASTEST 255ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (level != 0) level = 1; 256ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 257ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (level == Z_DEFAULT_COMPRESSION) level = 6; 258ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 259ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 260ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (windowBits < 0) { /* suppress zlib wrapper */ 261ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wrap = 0; 262ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov windowBits = -windowBits; 263ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 264ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef GZIP 265ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else if (windowBits > 15) { 266ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wrap = 2; /* write gzip wrapper instead */ 267ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov windowBits -= 16; 268ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 269ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 270ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED || 271ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov windowBits < 8 || windowBits > 15 || level < 0 || level > 9 || 272ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strategy < 0 || strategy > Z_FIXED) { 273ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 274ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 275ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (windowBits == 8) windowBits = 9; /* until 256-byte window bug fixed */ 276ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state)); 277ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s == Z_NULL) return Z_MEM_ERROR; 278ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->state = (struct internal_state FAR *)s; 279ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strm = strm; 280ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 281ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->wrap = wrap; 282ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->gzhead = Z_NULL; 283ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->w_bits = windowBits; 284ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->w_size = 1 << s->w_bits; 285ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->w_mask = s->w_size - 1; 286ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 287ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->hash_bits = memLevel + 7; 288ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->hash_size = 1 << s->hash_bits; 289ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->hash_mask = s->hash_size - 1; 290ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->hash_shift = ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH); 291ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 292ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte)); 293ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->prev = (Posf *) ZALLOC(strm, s->w_size, sizeof(Pos)); 294ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->head = (Posf *) ZALLOC(strm, s->hash_size, sizeof(Pos)); 295ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 296ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->high_water = 0; /* nothing written to s->window yet */ 297ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 298ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */ 299ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 300ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2); 301ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending_buf = (uchf *) overlay; 302ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L); 303ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 304ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL || 305ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending_buf == Z_NULL) { 306ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = FINISH_STATE; 307ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->msg = ERR_MSG(Z_MEM_ERROR); 308ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflateEnd (strm); 309ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_MEM_ERROR; 310ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 311ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->d_buf = overlay + s->lit_bufsize/sizeof(ush); 312ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize; 313ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 314ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->level = level; 315ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strategy = strategy; 316ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->method = (Byte)method; 317ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 318ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return deflateReset(strm); 319ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 320ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 321ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 322ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateSetDictionary ( 323ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 324ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov const Bytef *dictionary, 325ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt dictLength) 326ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 327ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 328ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt str, n; 329ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int wrap; 330ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov unsigned avail; 331ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_const unsigned char *next; 332ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 333ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL) 334ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 335ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = strm->state; 336ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wrap = s->wrap; 337ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (wrap == 2 || (wrap == 1 && s->status != INIT_STATE) || s->lookahead) 338ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 339ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 340ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* when using zlib wrappers, compute Adler-32 for provided dictionary */ 341ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (wrap == 1) 342ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = adler32(strm->adler, dictionary, dictLength); 343ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->wrap = 0; /* avoid computing Adler-32 in read_buf */ 344ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 345ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* if dictionary would fill window, just replace the history */ 346ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (dictLength >= s->w_size) { 347ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (wrap == 0) { /* already empty otherwise */ 348ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov CLEAR_HASH(s); 349ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart = 0; 350ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->block_start = 0L; 351ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = 0; 352ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 353ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov dictionary += dictLength - s->w_size; /* use the tail */ 354ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov dictLength = s->w_size; 355ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 356ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 357ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* insert dictionary into window and hash */ 358ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov avail = strm->avail_in; 359ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov next = strm->next_in; 360ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->avail_in = dictLength; 361ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->next_in = (z_const Bytef *)dictionary; 362ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fill_window(s); 363ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov while (s->lookahead >= MIN_MATCH) { 364ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov str = s->strstart; 365ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov n = s->lookahead - (MIN_MATCH-1); 366ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 367ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); 368ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 369ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->prev[str & s->w_mask] = s->head[s->ins_h]; 370ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 371ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->head[s->ins_h] = (Pos)str; 372ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov str++; 373ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (--n); 374ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart = str; 375ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead = MIN_MATCH-1; 376ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fill_window(s); 377ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 378ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart += s->lookahead; 379ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->block_start = (long)s->strstart; 380ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = s->lookahead; 381ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead = 0; 382ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = s->prev_length = MIN_MATCH-1; 383ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_available = 0; 384ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->next_in = next; 385ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->avail_in = avail; 386ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->wrap = wrap; 387ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 388ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 389ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 390ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 391ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateResetKeep ( 392ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm) 393ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 394ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 395ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 396ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL || 397ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0) { 398ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 399ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 400ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 401ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->total_in = strm->total_out = 0; 402ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ 403ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->data_type = Z_UNKNOWN; 404ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 405ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = (deflate_state *)strm->state; 406ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending = 0; 407ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending_out = s->pending_buf; 408ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 409ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->wrap < 0) { 410ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */ 411ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 412ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = s->wrap ? INIT_STATE : BUSY_STATE; 413ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = 414ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef GZIP 415ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->wrap == 2 ? crc32(0L, Z_NULL, 0) : 416ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 417ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov adler32(0L, Z_NULL, 0); 418ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->last_flush = Z_NO_FLUSH; 419ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 420ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_init(s); 421ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 422ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 423ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 424ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 425ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 426ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateReset ( 427ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm) 428ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 429ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int ret; 430ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 431ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ret = deflateResetKeep(strm); 432ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (ret == Z_OK) 433ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov lm_init(strm->state); 434ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return ret; 435ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 436ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 437ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 438ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateSetHeader (strm, head) 439ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm; 440ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov gz_headerp head; 441ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 442ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 443ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->state->wrap != 2) return Z_STREAM_ERROR; 444ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->state->gzhead = head; 445ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 446ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 447ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 448ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 449ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflatePending ( 450ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 451ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov unsigned *pending, 452ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int *bits) 453ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 454ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 455ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (pending != Z_NULL) 456ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *pending = strm->state->pending; 457ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bits != Z_NULL) 458ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *bits = strm->state->bi_valid; 459ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 460ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 461ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 462ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 463ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflatePrime (strm, bits, value) 464ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm; 465ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int bits; 466ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int value; 467ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 468ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 469ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int put; 470ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 471ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 472ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = strm->state; 473ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if ((Bytef *)(s->d_buf) < s->pending_out + ((Buf_size + 7) >> 3)) 474ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_BUF_ERROR; 475ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 476ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put = Buf_size - s->bi_valid; 477ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (put > bits) 478ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put = bits; 479ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->bi_buf |= (ush)((value & ((1 << put) - 1)) << s->bi_valid); 480ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->bi_valid += put; 481ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_flush_bits(s); 482ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov value >>= put; 483ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov bits -= put; 484ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (bits); 485ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 486ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 487ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 488ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 489ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateParams( 490ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 491ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int level, 492ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int strategy) 493ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 494ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 495ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov compress_func func; 496ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int err = Z_OK; 497ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 498ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 499ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = strm->state; 500ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 501ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef FASTEST 502ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (level != 0) level = 1; 503ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 504ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (level == Z_DEFAULT_COMPRESSION) level = 6; 505ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 506ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) { 507ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 508ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 509ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov func = configuration_table[s->level].func; 510ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 511ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if ((strategy != s->strategy || func != configuration_table[level].func) && 512ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->total_in != 0) { 513ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Flush the last buffer: */ 514ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov err = deflate(strm, Z_BLOCK); 515ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (err == Z_BUF_ERROR && s->pending == 0) 516ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov err = Z_OK; 517ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 518ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->level != level) { 519ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->level = level; 520ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->max_lazy_match = configuration_table[level].max_lazy; 521ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->good_match = configuration_table[level].good_length; 522ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->nice_match = configuration_table[level].nice_length; 523ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->max_chain_length = configuration_table[level].max_chain; 524ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 525ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strategy = strategy; 526ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return err; 527ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 528ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 529ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 530ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateTune( 531ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 532ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int good_length, 533ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int max_lazy, 534ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int nice_length, 535ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int max_chain) 536ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 537ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 538ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 539ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 540ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = strm->state; 541ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->good_match = good_length; 542ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->max_lazy_match = max_lazy; 543ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->nice_match = nice_length; 544ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->max_chain_length = max_chain; 545ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 546ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 547ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 548ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= 549ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * For the default windowBits of 15 and memLevel of 8, this function returns 550ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * a close to exact, as well as small, upper bound on the compressed size. 551ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * They are coded as constants here for a reason--if the #define's are 552ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * changed, then this function needs to be changed as well. The return 553ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * value for 15 and 8 only works for those exact settings. 554ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 555ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * For any setting other than those defaults for windowBits and memLevel, 556ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the value returned is a conservative worst case for the maximum expansion 557ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * resulting from using fixed blocks instead of stored blocks, which deflate 558ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * can emit on compressed data for some combinations of the parameters. 559ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 560ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * This function could be more sophisticated to provide closer upper bounds for 561ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * every combination of windowBits and memLevel. But even the conservative 562ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * upper bound of about 14% expansion does not seem onerous for output buffer 563ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * allocation. 564ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 565ee451cb395940862dad63c85adfe8f2fd55e864cSvet GanovuLong ZEXPORT deflateBound( 566ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 567ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uLong sourceLen) 568ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 569ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 570ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uLong complen, wraplen; 571ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Bytef *str; 572ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 573ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* conservative upper bound for compressed data */ 574ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov complen = sourceLen + 575ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 5; 576ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 577ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* if can't get parameters, return conservative bound plus zlib wrapper */ 578ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL) 579ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return complen + 6; 580ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 581ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* compute wrapper length */ 582ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = strm->state; 583ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov switch (s->wrap) { 584ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov case 0: /* raw deflate */ 585ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen = 0; 586ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; 587ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov case 1: /* zlib wrapper */ 588ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen = 6 + (s->strstart ? 4 : 0); 589ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; 590ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov case 2: /* gzip wrapper */ 591ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen = 18; 592ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead != Z_NULL) { /* user-supplied gzip header */ 593ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->extra != Z_NULL) 594ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen += 2 + s->gzhead->extra_len; 595ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov str = s->gzhead->name; 596ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (str != Z_NULL) 597ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 598ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen++; 599ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (*str++); 600ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov str = s->gzhead->comment; 601ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (str != Z_NULL) 602ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 603ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen++; 604ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (*str++); 605ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc) 606ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen += 2; 607ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 608ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; 609ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov default: /* for compiler happiness */ 610ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov wraplen = 6; 611ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 612ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 613ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* if not default parameters, return conservative bound */ 614ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->w_bits != 15 || s->hash_bits != 8 + 7) 615ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return complen + wraplen; 616ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 617ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* default settings: return tight bound for that case */ 618ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + 619ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (sourceLen >> 25) + 13 - 6 + wraplen; 620ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 621ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 622ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= 623ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Put a short in the pending buffer. The 16-bit value is put in MSB order. 624ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * IN assertion: the stream state is correct and there is enough room in 625ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * pending_buf. 626ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 627ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void putShortMSB ( 628ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 629ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt b) 630ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 631ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)(b >> 8)); 632ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)(b & 0xff)); 633ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 634ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 635ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= 636ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Flush as much pending output as possible. All deflate() output goes 637ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * through this function so some applications may wish to modify it 638ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * to avoid allocating a large strm->next_out buffer and copying into it. 639ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * (See also read_buf()). 640ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 641ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void flush_pending( 642ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm) 643ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 644ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov unsigned len; 645ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s = strm->state; 646ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 647ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_flush_bits(s); 648ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov len = s->pending; 649ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (len > strm->avail_out) len = strm->avail_out; 650ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (len == 0) return; 651ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 652ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy(strm->next_out, s->pending_out, len); 653ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->next_out += len; 654ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending_out += len; 655ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->total_out += len; 656ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->avail_out -= len; 657ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending -= len; 658ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending == 0) { 659ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending_out = s->pending_buf; 660ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 661ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 662ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 663ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 664ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflate ( 665ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 666ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int flush) 667ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 668ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int old_flush; /* value of flush param for previous deflate call */ 669ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s; 670ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 671ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL || 672ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush > Z_BLOCK || flush < 0) { 673ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 674ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 675ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s = strm->state; 676ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 677ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->next_out == Z_NULL || 678ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (strm->next_in == Z_NULL && strm->avail_in != 0) || 679ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->status == FINISH_STATE && flush != Z_FINISH)) { 680ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ERR_RETURN(strm, Z_STREAM_ERROR); 681ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 682ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR); 683ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 684ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strm = strm; /* just in case */ 685ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov old_flush = s->last_flush; 686ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->last_flush = flush; 687ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 688ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Write the header */ 689ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->status == INIT_STATE) { 690ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef GZIP 691ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->wrap == 2) { 692ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(0L, Z_NULL, 0); 693ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 31); 694ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 139); 695ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 8); 696ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead == Z_NULL) { 697ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 0); 698ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 0); 699ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 0); 700ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 0); 701ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, 0); 702ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, s->level == 9 ? 2 : 703ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ? 704ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 4 : 0)); 705ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, OS_CODE); 706ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = BUSY_STATE; 707ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 708ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else { 709ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (s->gzhead->text ? 1 : 0) + 710ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->gzhead->hcrc ? 2 : 0) + 711ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->gzhead->extra == Z_NULL ? 0 : 4) + 712ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->gzhead->name == Z_NULL ? 0 : 8) + 713ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->gzhead->comment == Z_NULL ? 0 : 16) 714ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ); 715ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)(s->gzhead->time & 0xff)); 716ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((s->gzhead->time >> 8) & 0xff)); 717ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((s->gzhead->time >> 16) & 0xff)); 718ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((s->gzhead->time >> 24) & 0xff)); 719ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, s->level == 9 ? 2 : 720ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ? 721ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 4 : 0)); 722ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, s->gzhead->os & 0xff); 723ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->extra != Z_NULL) { 724ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, s->gzhead->extra_len & 0xff); 725ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (s->gzhead->extra_len >> 8) & 0xff); 726ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 727ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc) 728ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, s->pending_buf, 729ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending); 730ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->gzindex = 0; 731ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = EXTRA_STATE; 732ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 733ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 734ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else 735ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 736ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov { 737ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8; 738ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt level_flags; 739ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 740ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2) 741ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov level_flags = 0; 742ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else if (s->level < 6) 743ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov level_flags = 1; 744ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else if (s->level == 6) 745ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov level_flags = 2; 746ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else 747ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov level_flags = 3; 748ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov header |= (level_flags << 6); 749ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strstart != 0) header |= PRESET_DICT; 750ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov header += 31 - (header % 31); 751ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 752ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = BUSY_STATE; 753ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov putShortMSB(s, header); 754ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 755ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Save the adler32 of the preset dictionary: */ 756ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strstart != 0) { 757ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov putShortMSB(s, (uInt)(strm->adler >> 16)); 758ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov putShortMSB(s, (uInt)(strm->adler & 0xffff)); 759ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 760ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = adler32(0L, Z_NULL, 0); 761ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 762ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 763ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef GZIP 764ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->status == EXTRA_STATE) { 765ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->extra != Z_NULL) { 766ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt beg = s->pending; /* start of bytes to update crc */ 767ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 768ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov while (s->gzindex < (s->gzhead->extra_len & 0xffff)) { 769ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending == s->pending_buf_size) { 770ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc && s->pending > beg) 771ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, s->pending_buf + beg, 772ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending - beg); 773ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(strm); 774ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov beg = s->pending; 775ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending == s->pending_buf_size) 776ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; 777ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 778ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, s->gzhead->extra[s->gzindex]); 779ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->gzindex++; 780ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 781ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc && s->pending > beg) 782ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, s->pending_buf + beg, 783ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending - beg); 784ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzindex == s->gzhead->extra_len) { 785ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->gzindex = 0; 786ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = NAME_STATE; 787ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 788ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 789ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else 790ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = NAME_STATE; 791ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 792ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->status == NAME_STATE) { 793ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->name != Z_NULL) { 794ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt beg = s->pending; /* start of bytes to update crc */ 795ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int val; 796ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 797ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 798ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending == s->pending_buf_size) { 799ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc && s->pending > beg) 800ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, s->pending_buf + beg, 801ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending - beg); 802ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(strm); 803ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov beg = s->pending; 804ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending == s->pending_buf_size) { 805ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov val = 1; 806ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; 807ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 808ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 809ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov val = s->gzhead->name[s->gzindex++]; 810ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, val); 811ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (val != 0); 812ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc && s->pending > beg) 813ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, s->pending_buf + beg, 814ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending - beg); 815ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (val == 0) { 816ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->gzindex = 0; 817ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = COMMENT_STATE; 818ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 819ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 820ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else 821ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = COMMENT_STATE; 822ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 823ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->status == COMMENT_STATE) { 824ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->comment != Z_NULL) { 825ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt beg = s->pending; /* start of bytes to update crc */ 826ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int val; 827ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 828ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 829ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending == s->pending_buf_size) { 830ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc && s->pending > beg) 831ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, s->pending_buf + beg, 832ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending - beg); 833ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(strm); 834ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov beg = s->pending; 835ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending == s->pending_buf_size) { 836ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov val = 1; 837ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; 838ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 839ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 840ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov val = s->gzhead->comment[s->gzindex++]; 841ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, val); 842ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (val != 0); 843ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc && s->pending > beg) 844ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, s->pending_buf + beg, 845ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->pending - beg); 846ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (val == 0) 847ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = HCRC_STATE; 848ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 849ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else 850ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = HCRC_STATE; 851ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 852ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->status == HCRC_STATE) { 853ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->gzhead->hcrc) { 854ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending + 2 > s->pending_buf_size) 855ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(strm); 856ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending + 2 <= s->pending_buf_size) { 857ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)(strm->adler & 0xff)); 858ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((strm->adler >> 8) & 0xff)); 859ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(0L, Z_NULL, 0); 860ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = BUSY_STATE; 861ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 862ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 863ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else 864ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = BUSY_STATE; 865ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 866ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 867ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 868ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Flush as much pending output as possible */ 869ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->pending != 0) { 870ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(strm); 871ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->avail_out == 0) { 872ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Since avail_out is 0, deflate will be called again with 873ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * more output space, but possibly with both pending and 874ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * avail_in equal to zero. There won't be anything to do, 875ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * but this is not an error situation so make sure we 876ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * return OK instead of BUF_ERROR at next call of deflate: 877ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 878ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->last_flush = -1; 879ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 880ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 881ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 882ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Make sure there is something to do and avoid duplicate consecutive 883ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * flushes. For repeated and useless calls with Z_FINISH, we keep 884ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * returning Z_STREAM_END instead of Z_BUF_ERROR. 885ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 886ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else if (strm->avail_in == 0 && RANK(flush) <= RANK(old_flush) && 887ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush != Z_FINISH) { 888ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ERR_RETURN(strm, Z_BUF_ERROR); 889ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 890ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 891ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* User must not provide more input after the first FINISH: */ 892ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->status == FINISH_STATE && strm->avail_in != 0) { 893ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ERR_RETURN(strm, Z_BUF_ERROR); 894ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 895ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 896ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Start a new block or continue the current one. 897ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 898ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->avail_in != 0 || s->lookahead != 0 || 899ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) { 900ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov block_state bstate; 901ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 902ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov bstate = s->strategy == Z_HUFFMAN_ONLY ? deflate_huff(s, flush) : 903ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (s->strategy == Z_RLE ? deflate_rle(s, flush) : 904ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (*(configuration_table[s->level].func))(s, flush)); 905ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 906ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bstate == finish_started || bstate == finish_done) { 907ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->status = FINISH_STATE; 908ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 909ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bstate == need_more || bstate == finish_started) { 910ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->avail_out == 0) { 911ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->last_flush = -1; /* avoid BUF_ERROR next call, see above */ 912ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 913ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 914ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If flush != Z_NO_FLUSH && avail_out == 0, the next call 915ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * of deflate should use the same flush parameter to make sure 916ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * that the flush is complete. So we don't have to output an 917ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * empty block here, this will be done at next call. This also 918ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * ensures that for a very small output buffer, we emit at most 919ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * one empty block. 920ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 921ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 922ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bstate == block_done) { 923ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_PARTIAL_FLUSH) { 924ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_align(s); 925ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else if (flush != Z_BLOCK) { /* FULL_FLUSH or SYNC_FLUSH */ 926ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_stored_block(s, (char*)0, 0L, 0); 927ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* For a full flush, this empty block will be recognized 928ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * as a special marker by inflate_sync(). 929ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 930ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_FULL_FLUSH) { 931ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov CLEAR_HASH(s); /* forget history */ 932ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0) { 933ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart = 0; 934ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->block_start = 0L; 935ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = 0; 936ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 937ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 938ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 939ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(strm); 940ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->avail_out == 0) { 941ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */ 942ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 943ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 944ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 945ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 946ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(strm->avail_out > 0, "bug2"); 947ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 948ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush != Z_FINISH) return Z_OK; 949ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->wrap <= 0) return Z_STREAM_END; 950ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 951ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Write the trailer */ 952ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef GZIP 953ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->wrap == 2) { 954ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)(strm->adler & 0xff)); 955ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((strm->adler >> 8) & 0xff)); 956ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((strm->adler >> 16) & 0xff)); 957ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((strm->adler >> 24) & 0xff)); 958ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)(strm->total_in & 0xff)); 959ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((strm->total_in >> 8) & 0xff)); 960ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((strm->total_in >> 16) & 0xff)); 961ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov put_byte(s, (Byte)((strm->total_in >> 24) & 0xff)); 962ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 963ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else 964ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 965ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov { 966ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov putShortMSB(s, (uInt)(strm->adler >> 16)); 967ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov putShortMSB(s, (uInt)(strm->adler & 0xffff)); 968ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 969ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(strm); 970ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If avail_out is zero, the application will call deflate again 971ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * to flush the rest. 972ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 973ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->wrap > 0) s->wrap = -s->wrap; /* write the trailer only once! */ 974ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return s->pending != 0 ? Z_OK : Z_STREAM_END; 975ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 976ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 977ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= */ 978ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateEnd ( 979ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm) 980ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 981ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int status; 982ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 983ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 984ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 985ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov status = strm->state->status; 986ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (status != INIT_STATE && 987ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov status != EXTRA_STATE && 988ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov status != NAME_STATE && 989ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov status != COMMENT_STATE && 990ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov status != HCRC_STATE && 991ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov status != BUSY_STATE && 992ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov status != FINISH_STATE) { 993ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 994ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 995ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 996ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Deallocate in reverse order of allocations: */ 997ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov TRY_FREE(strm, strm->state->pending_buf); 998ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov TRY_FREE(strm, strm->state->head); 999ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov TRY_FREE(strm, strm->state->prev); 1000ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov TRY_FREE(strm, strm->state->window); 1001ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1002ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ZFREE(strm, strm->state); 1003ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->state = Z_NULL; 1004ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1005ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK; 1006ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1007ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1008ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* ========================================================================= 1009ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Copy the source state to the destination state. 1010ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * To simplify the source, this is not supported for 16-bit MSDOS (which 1011ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * doesn't have enough memory anyway to duplicate compression states). 1012ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1013ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovint ZEXPORT deflateCopy ( 1014ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp dest, 1015ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp source) 1016ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1017ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef MAXSEG_64K 1018ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 1019ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 1020ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *ds; 1021ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *ss; 1022ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ushf *overlay; 1023ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1024ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1025ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) { 1026ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_STREAM_ERROR; 1027ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1028ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1029ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ss = source->state; 1030ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1031ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream)); 1032ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1033ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state)); 1034ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (ds == Z_NULL) return Z_MEM_ERROR; 1035ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov dest->state = (struct internal_state FAR *) ds; 1036ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy((voidpf)ds, (voidpf)ss, sizeof(deflate_state)); 1037ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->strm = dest; 1038ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1039ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte)); 1040ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos)); 1041ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos)); 1042ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2); 1043ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->pending_buf = (uchf *) overlay; 1044ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1045ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL || 1046ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->pending_buf == Z_NULL) { 1047ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflateEnd (dest); 1048ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_MEM_ERROR; 1049ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1050ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* following zmemcpy do not work for 16-bit MSDOS */ 1051ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte)); 1052ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy((voidpf)ds->prev, (voidpf)ss->prev, ds->w_size * sizeof(Pos)); 1053ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy((voidpf)ds->head, (voidpf)ss->head, ds->hash_size * sizeof(Pos)); 1054ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size); 1055ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1056ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf); 1057ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush); 1058ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize; 1059ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1060ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->l_desc.dyn_tree = ds->dyn_ltree; 1061ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->d_desc.dyn_tree = ds->dyn_dtree; 1062ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ds->bl_desc.dyn_tree = ds->bl_tree; 1063ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1064ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return Z_OK; 1065ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif /* MAXSEG_64K */ 1066ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1067ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1068ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1069ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Read a new buffer from the current input stream, update the adler32 1070ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * and total number of bytes read. All deflate() input goes through 1071ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * this function so some applications may wish to modify it to avoid 1072ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * allocating a large strm->next_in buffer and copying from it. 1073ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * (See also flush_pending()). 1074ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1075ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal int read_buf( 1076ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_streamp strm, 1077ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Bytef *buf, 1078ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov unsigned size) 1079ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1080ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov unsigned len = strm->avail_in; 1081ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1082ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (len > size) len = size; 1083ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (len == 0) return 0; 1084ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1085ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->avail_in -= len; 1086ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1087ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy(buf, strm->next_in, len); 1088ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (strm->state->wrap == 1) { 1089ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = adler32(strm->adler, buf, len); 1090ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1091ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef GZIP 1092ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else if (strm->state->wrap == 2) { 1093ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->adler = crc32(strm->adler, buf, len); 1094ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1095ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1096ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->next_in += len; 1097ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strm->total_in += len; 1098ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1099ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return (int)len; 1100ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1101ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1102ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1103ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Initialize the "longest match" routines for a new zlib stream 1104ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1105ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void lm_init ( 1106ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s) 1107ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1108ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->window_size = (ulg)2L*s->w_size; 1109ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1110ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov CLEAR_HASH(s); 1111ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1112ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Set the default configuration parameters: 1113ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1114ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->max_lazy_match = configuration_table[s->level].max_lazy; 1115ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->good_match = configuration_table[s->level].good_length; 1116ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->nice_match = configuration_table[s->level].nice_length; 1117ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->max_chain_length = configuration_table[s->level].max_chain; 1118ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1119ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart = 0; 1120ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->block_start = 0L; 1121ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead = 0; 1122ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = 0; 1123ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = s->prev_length = MIN_MATCH-1; 1124ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_available = 0; 1125ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->ins_h = 0; 1126ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 1127ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef ASMV 1128ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov match_init(); /* initialize the asm code */ 1129ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1130ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1131ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1132ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1133ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 1134ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1135ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Set match_start to the longest match starting at the given string and 1136ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * return its length. Matches shorter or equal to prev_length are discarded, 1137ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * in which case the result is equal to prev_length and match_start is 1138ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * garbage. 1139ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * IN assertions: cur_match is the head of the hash chain for the current 1140ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 1141ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * OUT assertion: the match length is not greater than s->lookahead. 1142ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1143ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef ASMV 1144ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* For 80x86 and 680x0, an optimized version will be provided in match.asm or 1145ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * match.S. The code will be functionally equivalent. 1146ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1147ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal uInt longest_match( 1148ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1149ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov IPos cur_match) /* current match */ 1150ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1151ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov unsigned chain_length = s->max_chain_length;/* max hash chain length */ 1152ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Bytef *scan = s->window + s->strstart; /* current string */ 1153ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Bytef *match; /* matched string */ 1154ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register int len; /* length of current match */ 1155ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int best_len = s->prev_length; /* best match length so far */ 1156ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int nice_match = s->nice_match; /* stop if match long enough */ 1157ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov IPos limit = s->strstart > (IPos)MAX_DIST(s) ? 1158ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart - (IPos)MAX_DIST(s) : NIL; 1159ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Stop when cur_match becomes <= limit. To simplify the code, 1160ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * we prevent matches with the string of window index 0. 1161ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1162ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Posf *prev = s->prev; 1163ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt wmask = s->w_mask; 1164ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1165ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef UNALIGNED_OK 1166ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Compare two bytes at a time. Note: this is not always beneficial. 1167ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Try with and without -DUNALIGNED_OK to check. 1168ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1169ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1; 1170ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register ush scan_start = *(ushf*)scan; 1171ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register ush scan_end = *(ushf*)(scan+best_len-1); 1172ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 1173ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Bytef *strend = s->window + s->strstart + MAX_MATCH; 1174ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Byte scan_end1 = scan[best_len-1]; 1175ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Byte scan_end = scan[best_len]; 1176ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1177ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1178ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. 1179ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * It is easy to get rid of this optimization if necessary. 1180ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1181ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); 1182ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1183ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Do not waste too much time if we already have a good match: */ 1184ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->prev_length >= s->good_match) { 1185ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov chain_length >>= 2; 1186ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1187ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Do not look for matches beyond the end of the input. This is necessary 1188ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * to make deflate deterministic. 1189ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1190ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead; 1191ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1192ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); 1193ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1194ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1195ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(cur_match < s->strstart, "no future"); 1196ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov match = s->window + cur_match; 1197ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1198ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Skip to next match if the match length cannot increase 1199ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * or if the match length is less than 2. Note that the checks below 1200ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * for insufficient lookahead only occur occasionally for performance 1201ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * reasons. Therefore uninitialized memory will be accessed, and 1202ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * conditional jumps will be made that depend on those values. 1203ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * However the length of the match is limited to the lookahead, so 1204ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the output of deflate is not affected by the uninitialized values. 1205ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1206ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#if (defined(UNALIGNED_OK) && MAX_MATCH == 258) 1207ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* This code assumes sizeof(unsigned short) == 2. Do not use 1208ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * UNALIGNED_OK if your compiler uses a different size. 1209ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1210ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (*(ushf*)(match+best_len-1) != scan_end || 1211ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *(ushf*)match != scan_start) continue; 1212ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1213ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* It is not necessary to compare scan[2] and match[2] since they are 1214ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * always equal when the other bytes match, given that the hash keys 1215ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at 1216ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * strstart+3, +5, ... up to strstart+257. We check for insufficient 1217ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * lookahead only every 4th comparison; the 128th check will be made 1218ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is 1219ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * necessary to put more guard bytes at the end of the window, or 1220ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * to check more often for insufficient lookahead. 1221ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1222ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(scan[2] == match[2], "scan[2]?"); 1223ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan++, match++; 1224ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1225ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1226ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1227ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1228ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1229ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan < strend); 1230ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* The funny "do {}" generates better code on most compilers */ 1231ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1232ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Here, scan <= window+strstart+257 */ 1233ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1234ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (*scan == *match) scan++; 1235ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1236ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov len = (MAX_MATCH - 1) - (int)(strend-scan); 1237ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan = strend - (MAX_MATCH-1); 1238ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1239ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else /* UNALIGNED_OK */ 1240ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1241ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (match[best_len] != scan_end || 1242ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov match[best_len-1] != scan_end1 || 1243ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *match != *scan || 1244ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *++match != scan[1]) continue; 1245ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1246ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* The check at best_len-1 can be removed because it will be made 1247ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * again later. (This heuristic is not always a win.) 1248ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * It is not necessary to compare scan[2] and match[2] since they 1249ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * are always equal when the other bytes match, given that 1250ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the hash keys are equal and that HASH_BITS >= 8. 1251ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1252ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan += 2, match++; 1253ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(*scan == *match, "match[2]?"); 1254ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1255ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* We check for insufficient lookahead only every 8th comparison; 1256ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the 256th check will be made at strstart+258. 1257ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1258ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1259ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (*++scan == *++match && *++scan == *++match && 1260ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *++scan == *++match && *++scan == *++match && 1261ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *++scan == *++match && *++scan == *++match && 1262ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *++scan == *++match && *++scan == *++match && 1263ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan < strend); 1264ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1265ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1266ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1267ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov len = MAX_MATCH - (int)(strend - scan); 1268ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan = strend - MAX_MATCH; 1269ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1270ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif /* UNALIGNED_OK */ 1271ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1272ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (len > best_len) { 1273ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_start = cur_match; 1274ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov best_len = len; 1275ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (len >= nice_match) break; 1276ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef UNALIGNED_OK 1277ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan_end = *(ushf*)(scan+best_len-1); 1278ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 1279ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan_end1 = scan[best_len-1]; 1280ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan_end = scan[best_len]; 1281ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1282ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1283ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while ((cur_match = prev[cur_match & wmask]) > limit 1284ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov && --chain_length != 0); 1285ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1286ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if ((uInt)best_len <= s->lookahead) return (uInt)best_len; 1287ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return s->lookahead; 1288ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1289ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif /* ASMV */ 1290ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1291ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else /* FASTEST */ 1292ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1293ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* --------------------------------------------------------------------------- 1294ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Optimized version for FASTEST only 1295ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1296ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal uInt longest_match( 1297ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1298ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov IPos cur_match) /* current match */ 1299ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1300ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Bytef *scan = s->window + s->strstart; /* current string */ 1301ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Bytef *match; /* matched string */ 1302ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register int len; /* length of current match */ 1303ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Bytef *strend = s->window + s->strstart + MAX_MATCH; 1304ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1305ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. 1306ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * It is easy to get rid of this optimization if necessary. 1307ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1308ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); 1309ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1310ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); 1311ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1312ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(cur_match < s->strstart, "no future"); 1313ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1314ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov match = s->window + cur_match; 1315ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1316ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Return failure if the match length is less than 2: 1317ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1318ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1; 1319ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1320ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* The check at best_len-1 can be removed because it will be made 1321ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * again later. (This heuristic is not always a win.) 1322ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * It is not necessary to compare scan[2] and match[2] since they 1323ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * are always equal when the other bytes match, given that 1324ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the hash keys are equal and that HASH_BITS >= 8. 1325ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1326ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan += 2, match += 2; 1327ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(*scan == *match, "match[2]?"); 1328ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1329ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* We check for insufficient lookahead only every 8th comparison; 1330ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the 256th check will be made at strstart+258. 1331ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1332ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1333ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (*++scan == *++match && *++scan == *++match && 1334ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *++scan == *++match && *++scan == *++match && 1335ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *++scan == *++match && *++scan == *++match && 1336ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *++scan == *++match && *++scan == *++match && 1337ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan < strend); 1338ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1339ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1340ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1341ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov len = MAX_MATCH - (int)(strend - scan); 1342ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1343ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (len < MIN_MATCH) return MIN_MATCH - 1; 1344ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1345ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_start = cur_match; 1346ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return (uInt)len <= s->lookahead ? (uInt)len : s->lookahead; 1347ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1348ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1349ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif /* FASTEST */ 1350ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1351ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifdef DEBUG 1352ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1353ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Check that the match at match_start is indeed a match. 1354ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1355ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void check_match( 1356ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1357ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov IPos start, IPos match, 1358ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int length) 1359ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1360ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* check that the match is indeed a match */ 1361ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (zmemcmp(s->window + match, 1362ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->window + start, length) != EQUAL) { 1363ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fprintf(stderr, " start %u, match %u, length %d\n", 1364ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov start, match, length); 1365ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1366ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fprintf(stderr, "%c%c", s->window[match++], s->window[start++]); 1367ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (--length != 0); 1368ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov z_error("invalid match"); 1369ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1370ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (z_verbose > 1) { 1371ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fprintf(stderr,"\\[%d,%d]", start-match, length); 1372ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { putc(s->window[start++], stderr); } while (--length != 0); 1373ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1374ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1375ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#else 1376ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov# define check_match(s, start, match, length) 1377ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif /* DEBUG */ 1378ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1379ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1380ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Fill the window when the lookahead becomes insufficient. 1381ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Updates strstart and lookahead. 1382ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * 1383ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * IN assertion: lookahead < MIN_LOOKAHEAD 1384ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD 1385ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * At least one byte has been read, or avail_in == 0; reads are 1386ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * performed for at least two bytes (required for the zip translate_eol 1387ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * option -- not supported here). 1388ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1389ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal void fill_window( 1390ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s) 1391ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1392ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register unsigned n, m; 1393ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov register Posf *p; 1394ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov unsigned more; /* Amount of free space at the end of the window. */ 1395ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt wsize = s->w_size; 1396ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1397ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead"); 1398ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1399ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1400ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); 1401ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1402ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Deal with !@#$% 64K limit: */ 1403ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (sizeof(int) <= 2) { 1404ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (more == 0 && s->strstart == 0 && s->lookahead == 0) { 1405ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov more = wsize; 1406ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1407ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else if (more == (unsigned)(-1)) { 1408ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Very unlikely, but possible on 16 bit machine if 1409ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * strstart == 0 && lookahead == 1 (input done a byte at time) 1410ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1411ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov more--; 1412ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1413ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1414ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1415ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If the window is almost full and there is insufficient lookahead, 1416ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * move the upper half to the lower one to make room in the upper half. 1417ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1418ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strstart >= wsize+MAX_DIST(s)) { 1419ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1420ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemcpy(s->window, s->window+wsize, (unsigned)wsize); 1421ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_start -= wsize; 1422ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ 1423ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->block_start -= (long) wsize; 1424ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1425ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Slide the hash table (could be avoided with 32 bit values 1426ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov at the expense of memory usage). We slide even when level == 0 1427ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov to keep the hash table consistent if we switch back to level > 0 1428ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov later. (Using level 0 permanently is not an optimal usage of 1429ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zlib, so we don't care about this pathological case.) 1430ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1431ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov n = s->hash_size; 1432ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov p = &s->head[n]; 1433ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1434ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov m = *--p; 1435ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *p = (Pos)(m >= wsize ? m-wsize : NIL); 1436ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (--n); 1437ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1438ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov n = wsize; 1439ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 1440ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov p = &s->prev[n]; 1441ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1442ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov m = *--p; 1443ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov *p = (Pos)(m >= wsize ? m-wsize : NIL); 1444ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If n is not on any hash chain, prev[n] is garbage but 1445ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * its value will never be used. 1446ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1447ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (--n); 1448ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1449ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov more += wsize; 1450ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1451ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strm->avail_in == 0) break; 1452ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1453ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If there was no sliding: 1454ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && 1455ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * more == window_size - lookahead - strstart 1456ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) 1457ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * => more >= window_size - 2*WSIZE + 2 1458ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * In the BIG_MEM or MMAP case (not yet supported), 1459ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * window_size == input_size + MIN_LOOKAHEAD && 1460ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. 1461ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Otherwise, window_size == 2*WSIZE so more >= 2. 1462ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * If there was sliding, more >= WSIZE. So in all cases, more >= 2. 1463ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1464ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(more >= 2, "more < 2"); 1465ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1466ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more); 1467ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead += n; 1468ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1469ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Initialize the hash value now that we have some input: */ 1470ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead + s->insert >= MIN_MATCH) { 1471ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt str = s->strstart - s->insert; 1472ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->ins_h = s->window[str]; 1473ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov UPDATE_HASH(s, s->ins_h, s->window[str + 1]); 1474ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#if MIN_MATCH != 3 1475ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Call UPDATE_HASH() MIN_MATCH-3 more times 1476ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1477ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov while (s->insert) { 1478ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); 1479ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 1480ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->prev[str & s->w_mask] = s->head[s->ins_h]; 1481ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1482ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->head[s->ins_h] = (Pos)str; 1483ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov str++; 1484ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert--; 1485ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead + s->insert < MIN_MATCH) 1486ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; 1487ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1488ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1489ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, 1490ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * but this is not important since only literal bytes will be emitted. 1491ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1492ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1493ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); 1494ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1495ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If the WIN_INIT bytes after the end of the current data have never been 1496ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * written, then zero those bytes in order to avoid memory check reports of 1497ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the use of uninitialized (or uninitialised as Julian writes) bytes by 1498ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the longest match routines. Update the high water mark for the next 1499ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * time through here. WIN_INIT is set to MAX_MATCH since the longest match 1500ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead. 1501ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1502ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->high_water < s->window_size) { 1503ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ulg curr = s->strstart + (ulg)(s->lookahead); 1504ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ulg init; 1505ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1506ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->high_water < curr) { 1507ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Previous high water mark below current data -- zero WIN_INIT 1508ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * bytes or up to end of window, whichever is less. 1509ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1510ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov init = s->window_size - curr; 1511ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (init > WIN_INIT) 1512ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov init = WIN_INIT; 1513ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemzero(s->window + curr, (unsigned)init); 1514ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->high_water = curr + init; 1515ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1516ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov else if (s->high_water < (ulg)curr + WIN_INIT) { 1517ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* High water mark at or above current data, but below current data 1518ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up 1519ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * to end of window, whichever is less. 1520ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1521ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov init = (ulg)curr + WIN_INIT - s->high_water; 1522ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (init > s->window_size - s->high_water) 1523ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov init = s->window_size - s->high_water; 1524ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov zmemzero(s->window + s->high_water, (unsigned)init); 1525ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->high_water += init; 1526ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1527ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1528ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1529ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD, 1530ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov "not enough room for search"); 1531ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1532ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1533ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1534ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Flush the current block, with given end-of-file flag. 1535ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * IN assertion: strstart is set to the end of the current match. 1536ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1537ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define FLUSH_BLOCK_ONLY(s, last) { \ 1538ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_flush_block(s, (s->block_start >= 0L ? \ 1539ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (charf *)&s->window[(unsigned)s->block_start] : \ 1540ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (charf *)Z_NULL), \ 1541ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (ulg)((long)s->strstart - s->block_start), \ 1542ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov (last)); \ 1543ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->block_start = s->strstart; \ 1544ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov flush_pending(s->strm); \ 1545ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Tracev((stderr,"[FLUSH]")); \ 1546ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1547ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1548ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* Same but force premature exit if necessary. */ 1549ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#define FLUSH_BLOCK(s, last) { \ 1550ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK_ONLY(s, last); \ 1551ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strm->avail_out == 0) return (last) ? finish_started : need_more; \ 1552ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1553ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1554ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1555ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Copy without compression as much as possible from the input stream, return 1556ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the current block state. 1557ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * This function does not insert new strings in the dictionary since 1558ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * uncompressible data is probably not useful. This function is used 1559ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * only for the level=0 compression option. 1560ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * NOTE: this function should be optimized to avoid extra copying from 1561ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * window to pending_buf. 1562ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1563ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_stored( 1564ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1565ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int flush) 1566ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1567ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Stored blocks are limited to 0xffff bytes, pending_buf is limited 1568ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * to pending_buf_size, and each stored block has a 5 byte header: 1569ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1570ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ulg max_block_size = 0xffff; 1571ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov ulg max_start; 1572ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1573ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (max_block_size > s->pending_buf_size - 5) { 1574ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov max_block_size = s->pending_buf_size - 5; 1575ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1576ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1577ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Copy as much as possible from input to output: */ 1578ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov for (;;) { 1579ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Fill the window as much as possible: */ 1580ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead <= 1) { 1581ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1582ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(s->strstart < s->w_size+MAX_DIST(s) || 1583ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->block_start >= (long)s->w_size, "slide too late"); 1584ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1585ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fill_window(s); 1586ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more; 1587ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1588ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0) break; /* flush the current block */ 1589ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1590ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(s->block_start >= 0L, "block gone"); 1591ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1592ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart += s->lookahead; 1593ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead = 0; 1594ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1595ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Emit a stored block if pending_buf will be full: */ 1596ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov max_start = s->block_start + max_block_size; 1597ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strstart == 0 || (ulg)s->strstart >= max_start) { 1598ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* strstart == 0 is possible when wraparound on 16-bit machine */ 1599ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead = (uInt)(s->strstart - max_start); 1600ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart = (uInt)max_start; 1601ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 0); 1602ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1603ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Flush if we may have to slide, otherwise block_start may become 1604ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * negative and the data will be gone: 1605ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1606ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) { 1607ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 0); 1608ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1609ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1610ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = 0; 1611ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_FINISH) { 1612ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 1); 1613ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return finish_done; 1614ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1615ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if ((long)s->strstart > s->block_start) 1616ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 0); 1617ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return block_done; 1618ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1619ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1620ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1621ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Compress as much as possible from the input stream, return the current 1622ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * block state. 1623ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * This function does not perform lazy evaluation of matches and inserts 1624ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * new strings in the dictionary only for unmatched strings or for short 1625ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * matches. It is used only for the fast compression options. 1626ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1627ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_fast( 1628ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1629ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int flush) 1630ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1631ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov IPos hash_head; /* head of the hash chain */ 1632ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int bflush; /* set if current block must be flushed */ 1633ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1634ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov for (;;) { 1635ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Make sure that we always have enough lookahead, except 1636ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * at the end of the input file. We need MAX_MATCH bytes 1637ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * for the next match, plus MIN_MATCH bytes to insert the 1638ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * string following the next match. 1639ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1640ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead < MIN_LOOKAHEAD) { 1641ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fill_window(s); 1642ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1643ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return need_more; 1644ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1645ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0) break; /* flush the current block */ 1646ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1647ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1648ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Insert the string window[strstart .. strstart+2] in the 1649ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * dictionary, and set hash_head to the head of the hash chain: 1650ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1651ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov hash_head = NIL; 1652ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead >= MIN_MATCH) { 1653ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov INSERT_STRING(s, s->strstart, hash_head); 1654ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1655ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1656ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Find the longest match, discarding those <= prev_length. 1657ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * At this point we have always match_length < MIN_MATCH 1658ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1659ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) { 1660ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* To simplify the code, we prevent matches with the string 1661ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * of window index 0 (in particular we have to avoid a match 1662ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * of the string with itself at the start of the input file). 1663ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1664ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = longest_match (s, hash_head); 1665ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* longest_match() sets match_start */ 1666ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1667ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->match_length >= MIN_MATCH) { 1668ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov check_match(s, s->strstart, s->match_start, s->match_length); 1669ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1670ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_dist(s, s->strstart - s->match_start, 1671ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length - MIN_MATCH, bflush); 1672ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1673ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead -= s->match_length; 1674ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1675ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Insert new strings in the hash table only if the match length 1676ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * is not too large. This saves time but degrades compression. 1677ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1678ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 1679ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->match_length <= s->max_insert_length && 1680ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead >= MIN_MATCH) { 1681ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length--; /* string at strstart already in table */ 1682ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1683ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1684ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov INSERT_STRING(s, s->strstart, hash_head); 1685ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* strstart never exceeds WSIZE-MAX_MATCH, so there are 1686ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * always MIN_MATCH bytes ahead. 1687ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1688ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (--s->match_length != 0); 1689ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1690ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else 1691ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1692ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov { 1693ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart += s->match_length; 1694ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = 0; 1695ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->ins_h = s->window[s->strstart]; 1696ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); 1697ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#if MIN_MATCH != 3 1698ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Call UPDATE_HASH() MIN_MATCH-3 more times 1699ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1700ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not 1701ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * matter since it will be recomputed at next deflate call. 1702ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1703ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1704ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else { 1705ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* No match, output a literal byte */ 1706ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Tracevv((stderr,"%c", s->window[s->strstart])); 1707ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_lit (s, s->window[s->strstart], bflush); 1708ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead--; 1709ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1710ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1711ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bflush) FLUSH_BLOCK(s, 0); 1712ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1713ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = s->strstart < MIN_MATCH-1 ? s->strstart : MIN_MATCH-1; 1714ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_FINISH) { 1715ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 1); 1716ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return finish_done; 1717ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1718ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->last_lit) 1719ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 0); 1720ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return block_done; 1721ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1722ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1723ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#ifndef FASTEST 1724ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1725ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * Same as above, but achieves better compression. We use a lazy 1726ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * evaluation for matches: a match is finally adopted only if there is 1727ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * no better match at the next window position. 1728ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1729ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_slow( 1730ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1731ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int flush) 1732ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1733ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov IPos hash_head; /* head of hash chain */ 1734ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int bflush; /* set if current block must be flushed */ 1735ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1736ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Process the input block. */ 1737ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov for (;;) { 1738ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Make sure that we always have enough lookahead, except 1739ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * at the end of the input file. We need MAX_MATCH bytes 1740ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * for the next match, plus MIN_MATCH bytes to insert the 1741ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * string following the next match. 1742ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1743ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead < MIN_LOOKAHEAD) { 1744ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fill_window(s); 1745ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1746ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return need_more; 1747ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1748ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0) break; /* flush the current block */ 1749ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1750ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1751ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Insert the string window[strstart .. strstart+2] in the 1752ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * dictionary, and set hash_head to the head of the hash chain: 1753ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1754ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov hash_head = NIL; 1755ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead >= MIN_MATCH) { 1756ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov INSERT_STRING(s, s->strstart, hash_head); 1757ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1758ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1759ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Find the longest match, discarding those <= prev_length. 1760ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1761ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->prev_length = s->match_length, s->prev_match = s->match_start; 1762ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = MIN_MATCH-1; 1763ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1764ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (hash_head != NIL && s->prev_length < s->max_lazy_match && 1765ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart - hash_head <= MAX_DIST(s)) { 1766ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* To simplify the code, we prevent matches with the string 1767ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * of window index 0 (in particular we have to avoid a match 1768ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * of the string with itself at the start of the input file). 1769ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1770ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = longest_match (s, hash_head); 1771ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* longest_match() sets match_start */ 1772ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1773ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->match_length <= 5 && (s->strategy == Z_FILTERED 1774ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#if TOO_FAR <= 32767 1775ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov || (s->match_length == MIN_MATCH && 1776ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart - s->match_start > TOO_FAR) 1777ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif 1778ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov )) { 1779ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1780ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If prev_match is also MIN_MATCH, match_start is garbage 1781ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * but we will ignore the current match anyway. 1782ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1783ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = MIN_MATCH-1; 1784ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1785ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1786ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If there was a match at the previous step and the current 1787ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * match is not better, output the previous match: 1788ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1789ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) { 1790ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt max_insert = s->strstart + s->lookahead - MIN_MATCH; 1791ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Do not insert strings in hash table beyond this. */ 1792ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1793ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov check_match(s, s->strstart-1, s->prev_match, s->prev_length); 1794ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1795ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_dist(s, s->strstart -1 - s->prev_match, 1796ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->prev_length - MIN_MATCH, bflush); 1797ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1798ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Insert in hash table all strings up to the end of the match. 1799ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * strstart-1 and strstart are already inserted. If there is not 1800ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * enough lookahead, the last two strings are not inserted in 1801ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the hash table. 1802ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1803ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead -= s->prev_length-1; 1804ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->prev_length -= 2; 1805ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1806ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (++s->strstart <= max_insert) { 1807ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov INSERT_STRING(s, s->strstart, hash_head); 1808ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1809ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (--s->prev_length != 0); 1810ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_available = 0; 1811ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = MIN_MATCH-1; 1812ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1813ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1814ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bflush) FLUSH_BLOCK(s, 0); 1815ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1816ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else if (s->match_available) { 1817ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* If there was no match at the previous position, output a 1818ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * single literal. If there was a match but the current match 1819ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * is longer, truncate the previous match to a single literal. 1820ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1821ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Tracevv((stderr,"%c", s->window[s->strstart-1])); 1822ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_lit(s, s->window[s->strstart-1], bflush); 1823ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bflush) { 1824ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK_ONLY(s, 0); 1825ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1826ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1827ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead--; 1828ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->strm->avail_out == 0) return need_more; 1829ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else { 1830ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* There is no previous match to compare with, wait for 1831ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * the next step to decide. 1832ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1833ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_available = 1; 1834ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1835ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead--; 1836ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1837ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1838ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert (flush != Z_NO_FLUSH, "no flush?"); 1839ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->match_available) { 1840ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Tracevv((stderr,"%c", s->window[s->strstart-1])); 1841ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_lit(s, s->window[s->strstart-1], bflush); 1842ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_available = 0; 1843ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1844ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = s->strstart < MIN_MATCH-1 ? s->strstart : MIN_MATCH-1; 1845ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_FINISH) { 1846ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 1); 1847ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return finish_done; 1848ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1849ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->last_lit) 1850ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 0); 1851ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return block_done; 1852ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1853ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov#endif /* FASTEST */ 1854ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1855ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1856ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * For Z_RLE, simply look for runs of bytes, generate matches only of distance 1857ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * one. Do not maintain a hash table. (It will be regenerated if this run of 1858ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * deflate switches away from Z_RLE.) 1859ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1860ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_rle( 1861ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1862ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int flush) 1863ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1864ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int bflush; /* set if current block must be flushed */ 1865ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov uInt prev; /* byte at distance one to match */ 1866ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Bytef *scan, *strend; /* scan goes up to strend for length of run */ 1867ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1868ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov for (;;) { 1869ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Make sure that we always have enough lookahead, except 1870ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * at the end of the input file. We need MAX_MATCH bytes 1871ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * for the longest run, plus one for the unrolled loop. 1872ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1873ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead <= MAX_MATCH) { 1874ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fill_window(s); 1875ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead <= MAX_MATCH && flush == Z_NO_FLUSH) { 1876ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return need_more; 1877ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1878ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0) break; /* flush the current block */ 1879ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1880ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1881ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* See how many times the previous byte repeats */ 1882ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = 0; 1883ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead >= MIN_MATCH && s->strstart > 0) { 1884ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan = s->window + s->strstart - 1; 1885ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov prev = *scan; 1886ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (prev == *++scan && prev == *++scan && prev == *++scan) { 1887ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov strend = s->window + s->strstart + MAX_MATCH; 1888ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov do { 1889ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } while (prev == *++scan && prev == *++scan && 1890ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov prev == *++scan && prev == *++scan && 1891ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov prev == *++scan && prev == *++scan && 1892ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov prev == *++scan && prev == *++scan && 1893ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov scan < strend); 1894ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = MAX_MATCH - (int)(strend - scan); 1895ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->match_length > s->lookahead) 1896ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = s->lookahead; 1897ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1898ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Assert(scan <= s->window+(uInt)(s->window_size-1), "wild scan"); 1899ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1900ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1901ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Emit match if have run of MIN_MATCH or longer, else emit literal */ 1902ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->match_length >= MIN_MATCH) { 1903ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov check_match(s, s->strstart, s->strstart - 1, s->match_length); 1904ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1905ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_dist(s, 1, s->match_length - MIN_MATCH, bflush); 1906ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1907ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead -= s->match_length; 1908ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart += s->match_length; 1909ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = 0; 1910ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } else { 1911ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* No match, output a literal byte */ 1912ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Tracevv((stderr,"%c", s->window[s->strstart])); 1913ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_lit (s, s->window[s->strstart], bflush); 1914ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead--; 1915ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1916ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1917ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bflush) FLUSH_BLOCK(s, 0); 1918ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1919ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = 0; 1920ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_FINISH) { 1921ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 1); 1922ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return finish_done; 1923ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1924ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->last_lit) 1925ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 0); 1926ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return block_done; 1927ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1928ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1929ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov/* =========================================================================== 1930ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * For Z_HUFFMAN_ONLY, do not look for matches. Do not maintain a hash table. 1931ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov * (It will be regenerated if this run of deflate switches away from Huffman.) 1932ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov */ 1933ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganovlocal block_state deflate_huff( 1934ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov deflate_state *s, 1935ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int flush) 1936ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov{ 1937ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov int bflush; /* set if current block must be flushed */ 1938ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1939ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov for (;;) { 1940ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Make sure that we have a literal to write. */ 1941ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0) { 1942ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov fill_window(s); 1943ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->lookahead == 0) { 1944ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_NO_FLUSH) 1945ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return need_more; 1946ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov break; /* flush the current block */ 1947ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1948ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1949ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov 1950ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov /* Output a literal byte */ 1951ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->match_length = 0; 1952ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov Tracevv((stderr,"%c", s->window[s->strstart])); 1953ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov _tr_tally_lit (s, s->window[s->strstart], bflush); 1954ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->lookahead--; 1955ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->strstart++; 1956ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (bflush) FLUSH_BLOCK(s, 0); 1957ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1958ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov s->insert = 0; 1959ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (flush == Z_FINISH) { 1960ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 1); 1961ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return finish_done; 1962ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov } 1963ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov if (s->last_lit) 1964ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov FLUSH_BLOCK(s, 0); 1965ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov return block_done; 1966ee451cb395940862dad63c85adfe8f2fd55e864cSvet Ganov} 1967