811 deflateEnd (strm); 812 return Z_MEM_ERROR; 813 } 814 s->d_buf = overlay + s->lit_bufsize/sizeof(ush); 815 s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize; 816 817 s->level = level; 818 s->strategy = strategy; 819 s->method = (Byte)method; 820 821 return deflateReset(strm); 822} 823 824/* ========================================================================= */ 825int deflateSetDictionary (strm, dictionary, dictLength) 826 z_streamp strm; 827 const Bytef *dictionary; 828 uInt dictLength; 829{ 830 deflate_state *s; 831 uInt length = dictLength; 832 uInt n; 833 IPos hash_head = 0; 834 835 if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL) 836 return Z_STREAM_ERROR; 837 838 s = (deflate_state *) strm->state; 839 if (s->status != INIT_STATE) return Z_STREAM_ERROR; 840 841 strm->adler = adler32(strm->adler, dictionary, dictLength); 842 843 if (length < MIN_MATCH) return Z_OK; 844 if (length > MAX_DIST(s)) { 845 length = MAX_DIST(s); 846#ifndef USE_DICT_HEAD 847 dictionary += dictLength - length; /* use the tail of the dictionary */ 848#endif 849 } 850 zmemcpy((charf *)s->window, dictionary, length); 851 s->strstart = length; 852 s->block_start = (long)length; 853 854 /* Insert all strings in the hash table (except for the last two bytes). 855 * s->lookahead stays null, so s->ins_h will be recomputed at the next 856 * call of fill_window. 857 */ 858 s->ins_h = s->window[0]; 859 UPDATE_HASH(s, s->ins_h, s->window[1]); 860 for (n = 0; n <= length - MIN_MATCH; n++) { 861 INSERT_STRING(s, n, hash_head); 862 } 863 if (hash_head) hash_head = 0; /* to make compiler happy */ 864 return Z_OK; 865} 866 867/* ========================================================================= */ 868int deflateReset (strm) 869 z_streamp strm; 870{ 871 deflate_state *s; 872 873 if (strm == Z_NULL || strm->state == Z_NULL || 874 strm->zalloc == Z_NULL || strm->zfree == Z_NULL) return Z_STREAM_ERROR; 875 876 strm->total_in = strm->total_out = 0; 877 strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */ 878 strm->data_type = Z_UNKNOWN; 879 880 s = (deflate_state *)strm->state; 881 s->pending = 0; 882 s->pending_out = s->pending_buf; 883 884 if (s->noheader < 0) { 885 s->noheader = 0; /* was set to -1 by deflate(..., Z_FINISH); */ 886 } 887 s->status = s->noheader ? BUSY_STATE : INIT_STATE; 888 strm->adler = 1; 889 s->last_flush = Z_NO_FLUSH; 890 891 _tr_init(s); 892 lm_init(s); 893 894 return Z_OK; 895} 896 897/* ========================================================================= */ 898int deflateParams(strm, level, strategy) 899 z_streamp strm; 900 int level; 901 int strategy; 902{ 903 deflate_state *s; 904 compress_func func; 905 int err = Z_OK; 906 907 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 908 s = (deflate_state *) strm->state; 909 910 if (level == Z_DEFAULT_COMPRESSION) { 911 level = 6; 912 } 913 if (level < 0 || level > 9 || strategy < 0 || strategy > Z_HUFFMAN_ONLY) { 914 return Z_STREAM_ERROR; 915 } 916 func = configuration_table[s->level].func; 917 918 if (func != configuration_table[level].func && strm->total_in != 0) { 919 /* Flush the last buffer: */ 920 err = deflate(strm, Z_PARTIAL_FLUSH); 921 } 922 if (s->level != level) { 923 s->level = level; 924 s->max_lazy_match = configuration_table[level].max_lazy; 925 s->good_match = configuration_table[level].good_length; 926 s->nice_match = configuration_table[level].nice_length; 927 s->max_chain_length = configuration_table[level].max_chain; 928 } 929 s->strategy = strategy; 930 return err; 931} 932 933/* ========================================================================= 934 * Put a short in the pending buffer. The 16-bit value is put in MSB order. 935 * IN assertion: the stream state is correct and there is enough room in 936 * pending_buf. 937 */ 938local void putShortMSB (s, b) 939 deflate_state *s; 940 uInt b; 941{ 942 put_byte(s, (Byte)(b >> 8)); 943 put_byte(s, (Byte)(b & 0xff)); 944} 945 946/* ========================================================================= 947 * Flush as much pending output as possible. All deflate() output goes 948 * through this function so some applications may wish to modify it 949 * to avoid allocating a large strm->next_out buffer and copying into it. 950 * (See also read_buf()). 951 */ 952local void flush_pending(strm) 953 z_streamp strm; 954{ 955 deflate_state *s = (deflate_state *) strm->state; 956 unsigned len = s->pending; 957 958 if (len > strm->avail_out) len = strm->avail_out; 959 if (len == 0) return; 960 961 if (strm->next_out != Z_NULL) { 962 zmemcpy(strm->next_out, s->pending_out, len); 963 strm->next_out += len; 964 } 965 s->pending_out += len; 966 strm->total_out += len; 967 strm->avail_out -= len; 968 s->pending -= len; 969 if (s->pending == 0) { 970 s->pending_out = s->pending_buf; 971 } 972} 973 974/* ========================================================================= */ 975int deflate (strm, flush) 976 z_streamp strm; 977 int flush; 978{ 979 int old_flush; /* value of flush param for previous deflate call */ 980 deflate_state *s; 981 982 if (strm == Z_NULL || strm->state == Z_NULL || 983 flush > Z_FINISH || flush < 0) { 984 return Z_STREAM_ERROR; 985 } 986 s = (deflate_state *) strm->state; 987 988 if ((strm->next_in == Z_NULL && strm->avail_in != 0) || 989 (s->status == FINISH_STATE && flush != Z_FINISH)) { 990 ERR_RETURN(strm, Z_STREAM_ERROR); 991 } 992 if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR); 993 994 s->strm = strm; /* just in case */ 995 old_flush = s->last_flush; 996 s->last_flush = flush; 997 998 /* Write the zlib header */ 999 if (s->status == INIT_STATE) { 1000 1001 uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8; 1002 uInt level_flags = (s->level-1) >> 1; 1003 1004 if (level_flags > 3) level_flags = 3; 1005 header |= (level_flags << 6); 1006 if (s->strstart != 0) header |= PRESET_DICT; 1007 header += 31 - (header % 31); 1008 1009 s->status = BUSY_STATE; 1010 putShortMSB(s, header); 1011 1012 /* Save the adler32 of the preset dictionary: */ 1013 if (s->strstart != 0) { 1014 putShortMSB(s, (uInt)(strm->adler >> 16)); 1015 putShortMSB(s, (uInt)(strm->adler & 0xffff)); 1016 } 1017 strm->adler = 1L; 1018 } 1019 1020 /* Flush as much pending output as possible */ 1021 if (s->pending != 0) { 1022 flush_pending(strm); 1023 if (strm->avail_out == 0) { 1024 /* Since avail_out is 0, deflate will be called again with 1025 * more output space, but possibly with both pending and 1026 * avail_in equal to zero. There won't be anything to do, 1027 * but this is not an error situation so make sure we 1028 * return OK instead of BUF_ERROR at next call of deflate: 1029 */ 1030 s->last_flush = -1; 1031 return Z_OK; 1032 } 1033 1034 /* Make sure there is something to do and avoid duplicate consecutive 1035 * flushes. For repeated and useless calls with Z_FINISH, we keep 1036 * returning Z_STREAM_END instead of Z_BUFF_ERROR. 1037 */ 1038 } else if (strm->avail_in == 0 && flush <= old_flush && 1039 flush != Z_FINISH) { 1040 ERR_RETURN(strm, Z_BUF_ERROR); 1041 } 1042 1043 /* User must not provide more input after the first FINISH: */ 1044 if (s->status == FINISH_STATE && strm->avail_in != 0) { 1045 ERR_RETURN(strm, Z_BUF_ERROR); 1046 } 1047 1048 /* Start a new block or continue the current one. 1049 */ 1050 if (strm->avail_in != 0 || s->lookahead != 0 || 1051 (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) { 1052 block_state bstate; 1053 1054 bstate = (*(configuration_table[s->level].func))(s, flush); 1055 1056 if (bstate == finish_started || bstate == finish_done) { 1057 s->status = FINISH_STATE; 1058 } 1059 if (bstate == need_more || bstate == finish_started) { 1060 if (strm->avail_out == 0) { 1061 s->last_flush = -1; /* avoid BUF_ERROR next call, see above */ 1062 } 1063 return Z_OK; 1064 /* If flush != Z_NO_FLUSH && avail_out == 0, the next call 1065 * of deflate should use the same flush parameter to make sure 1066 * that the flush is complete. So we don't have to output an 1067 * empty block here, this will be done at next call. This also 1068 * ensures that for a very small output buffer, we emit at most 1069 * one empty block. 1070 */ 1071 } 1072 if (bstate == block_done) { 1073 if (flush == Z_PARTIAL_FLUSH) { 1074 _tr_align(s); 1075 } else if (flush == Z_PACKET_FLUSH) { 1076 /* Output just the 3-bit `stored' block type value, 1077 but not a zero length. */ 1078 _tr_stored_type_only(s); 1079 } else { /* FULL_FLUSH or SYNC_FLUSH */ 1080 _tr_stored_block(s, (char*)0, 0L, 0); 1081 /* For a full flush, this empty block will be recognized 1082 * as a special marker by inflate_sync(). 1083 */ 1084 if (flush == Z_FULL_FLUSH) { 1085 CLEAR_HASH(s); /* forget history */ 1086 } 1087 } 1088 flush_pending(strm); 1089 if (strm->avail_out == 0) { 1090 s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */ 1091 return Z_OK; 1092 } 1093 } 1094 } 1095 Assert(strm->avail_out > 0, "bug2"); 1096 1097 if (flush != Z_FINISH) return Z_OK; 1098 if (s->noheader) return Z_STREAM_END; 1099 1100 /* Write the zlib trailer (adler32) */ 1101 putShortMSB(s, (uInt)(strm->adler >> 16)); 1102 putShortMSB(s, (uInt)(strm->adler & 0xffff)); 1103 flush_pending(strm); 1104 /* If avail_out is zero, the application will call deflate again 1105 * to flush the rest. 1106 */ 1107 s->noheader = -1; /* write the trailer only once! */ 1108 return s->pending != 0 ? Z_OK : Z_STREAM_END; 1109} 1110 1111/* ========================================================================= */ 1112int deflateEnd (strm) 1113 z_streamp strm; 1114{ 1115 int status; 1116 deflate_state *s; 1117 1118 if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; 1119 s = (deflate_state *) strm->state; 1120 1121 status = s->status; 1122 if (status != INIT_STATE && status != BUSY_STATE && 1123 status != FINISH_STATE) { 1124 return Z_STREAM_ERROR; 1125 } 1126 1127 /* Deallocate in reverse order of allocations: */ 1128 TRY_FREE(strm, s->pending_buf); 1129 TRY_FREE(strm, s->head); 1130 TRY_FREE(strm, s->prev); 1131 TRY_FREE(strm, s->window); 1132 1133 ZFREE(strm, s); 1134 strm->state = Z_NULL; 1135 1136 return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK; 1137} 1138 1139/* ========================================================================= 1140 * Copy the source state to the destination state. 1141 */ 1142int deflateCopy (dest, source) 1143 z_streamp dest; 1144 z_streamp source; 1145{ 1146 deflate_state *ds; 1147 deflate_state *ss; 1148 ushf *overlay; 1149 1150 if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) 1151 return Z_STREAM_ERROR; 1152 ss = (deflate_state *) source->state; 1153 1154 zmemcpy(dest, source, sizeof(*dest)); 1155 1156 ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state)); 1157 if (ds == Z_NULL) return Z_MEM_ERROR; 1158 dest->state = (struct internal_state FAR *) ds; 1159 zmemcpy(ds, ss, sizeof(*ds)); 1160 ds->strm = dest; 1161 1162 ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte)); 1163 ds->prev = (Posf *) ZALLOC(dest, ds->w_size, sizeof(Pos)); 1164 ds->head = (Posf *) ZALLOC(dest, ds->hash_size, sizeof(Pos)); 1165 overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2); 1166 ds->pending_buf = (uchf *) overlay; 1167 1168 if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL || 1169 ds->pending_buf == Z_NULL) { 1170 deflateEnd (dest); 1171 return Z_MEM_ERROR; 1172 } 1173 /* ??? following zmemcpy doesn't work for 16-bit MSDOS */ 1174 zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte)); 1175 zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos)); 1176 zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos)); 1177 zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size); 1178 1179 ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf); 1180 ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush); 1181 ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize; 1182 1183 ds->l_desc.dyn_tree = ds->dyn_ltree; 1184 ds->d_desc.dyn_tree = ds->dyn_dtree; 1185 ds->bl_desc.dyn_tree = ds->bl_tree; 1186 1187 return Z_OK; 1188} 1189 1190/* =========================================================================== 1191 * Return the number of bytes of output which are immediately available 1192 * for output from the decompressor. 1193 */ 1194int deflateOutputPending (strm) 1195 z_streamp strm; 1196{ 1197 if (strm == Z_NULL || strm->state == Z_NULL) return 0; 1198 1199 return ((deflate_state *)(strm->state))->pending; 1200} 1201 1202/* =========================================================================== 1203 * Read a new buffer from the current input stream, update the adler32 1204 * and total number of bytes read. All deflate() input goes through 1205 * this function so some applications may wish to modify it to avoid 1206 * allocating a large strm->next_in buffer and copying from it. 1207 * (See also flush_pending()). 1208 */ 1209local int read_buf(strm, buf, size) 1210 z_streamp strm; 1211 charf *buf; 1212 unsigned size; 1213{ 1214 unsigned len = strm->avail_in; 1215 1216 if (len > size) len = size; 1217 if (len == 0) return 0; 1218 1219 strm->avail_in -= len; 1220 1221 if (!((deflate_state *)(strm->state))->noheader) { 1222 strm->adler = adler32(strm->adler, strm->next_in, len); 1223 } 1224 zmemcpy(buf, strm->next_in, len); 1225 strm->next_in += len; 1226 strm->total_in += len; 1227 1228 return (int)len; 1229} 1230 1231/* =========================================================================== 1232 * Initialize the "longest match" routines for a new zlib stream 1233 */ 1234local void lm_init (s) 1235 deflate_state *s; 1236{ 1237 s->window_size = (ulg)2L*s->w_size; 1238 1239 CLEAR_HASH(s); 1240 1241 /* Set the default configuration parameters: 1242 */ 1243 s->max_lazy_match = configuration_table[s->level].max_lazy; 1244 s->good_match = configuration_table[s->level].good_length; 1245 s->nice_match = configuration_table[s->level].nice_length; 1246 s->max_chain_length = configuration_table[s->level].max_chain; 1247 1248 s->strstart = 0; 1249 s->block_start = 0L; 1250 s->lookahead = 0; 1251 s->match_length = s->prev_length = MIN_MATCH-1; 1252 s->match_available = 0; 1253 s->ins_h = 0; 1254#ifdef ASMV 1255 match_init(); /* initialize the asm code */ 1256#endif 1257} 1258 1259/* =========================================================================== 1260 * Set match_start to the longest match starting at the given string and 1261 * return its length. Matches shorter or equal to prev_length are discarded, 1262 * in which case the result is equal to prev_length and match_start is 1263 * garbage. 1264 * IN assertions: cur_match is the head of the hash chain for the current 1265 * string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1 1266 * OUT assertion: the match length is not greater than s->lookahead. 1267 */ 1268#ifndef ASMV 1269/* For 80x86 and 680x0, an optimized version will be provided in match.asm or 1270 * match.S. The code will be functionally equivalent. 1271 */ 1272local uInt longest_match(s, cur_match) 1273 deflate_state *s; 1274 IPos cur_match; /* current match */ 1275{ 1276 unsigned chain_length = s->max_chain_length;/* max hash chain length */ 1277 register Bytef *scan = s->window + s->strstart; /* current string */ 1278 register Bytef *match; /* matched string */ 1279 register int len; /* length of current match */ 1280 int best_len = s->prev_length; /* best match length so far */ 1281 int nice_match = s->nice_match; /* stop if match long enough */ 1282 IPos limit = s->strstart > (IPos)MAX_DIST(s) ? 1283 s->strstart - (IPos)MAX_DIST(s) : NIL; 1284 /* Stop when cur_match becomes <= limit. To simplify the code, 1285 * we prevent matches with the string of window index 0. 1286 */ 1287 Posf *prev = s->prev; 1288 uInt wmask = s->w_mask; 1289 1290#ifdef UNALIGNED_OK 1291 /* Compare two bytes at a time. Note: this is not always beneficial. 1292 * Try with and without -DUNALIGNED_OK to check. 1293 */ 1294 register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1; 1295 register ush scan_start = *(ushf*)scan; 1296 register ush scan_end = *(ushf*)(scan+best_len-1); 1297#else 1298 register Bytef *strend = s->window + s->strstart + MAX_MATCH; 1299 register Byte scan_end1 = scan[best_len-1]; 1300 register Byte scan_end = scan[best_len]; 1301#endif 1302 1303 /* The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16. 1304 * It is easy to get rid of this optimization if necessary. 1305 */ 1306 Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever"); 1307 1308 /* Do not waste too much time if we already have a good match: */ 1309 if (s->prev_length >= s->good_match) { 1310 chain_length >>= 2; 1311 } 1312 /* Do not look for matches beyond the end of the input. This is necessary 1313 * to make deflate deterministic. 1314 */ 1315 if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead; 1316 1317 Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead"); 1318 1319 do { 1320 Assert(cur_match < s->strstart, "no future"); 1321 match = s->window + cur_match; 1322 1323 /* Skip to next match if the match length cannot increase 1324 * or if the match length is less than 2: 1325 */ 1326#if (defined(UNALIGNED_OK) && MAX_MATCH == 258) 1327 /* This code assumes sizeof(unsigned short) == 2. Do not use 1328 * UNALIGNED_OK if your compiler uses a different size. 1329 */ 1330 if (*(ushf*)(match+best_len-1) != scan_end || 1331 *(ushf*)match != scan_start) continue; 1332 1333 /* It is not necessary to compare scan[2] and match[2] since they are 1334 * always equal when the other bytes match, given that the hash keys 1335 * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at 1336 * strstart+3, +5, ... up to strstart+257. We check for insufficient 1337 * lookahead only every 4th comparison; the 128th check will be made 1338 * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is 1339 * necessary to put more guard bytes at the end of the window, or 1340 * to check more often for insufficient lookahead. 1341 */ 1342 Assert(scan[2] == match[2], "scan[2]?"); 1343 scan++, match++; 1344 do { 1345 } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1346 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1347 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1348 *(ushf*)(scan+=2) == *(ushf*)(match+=2) && 1349 scan < strend); 1350 /* The funny "do {}" generates better code on most compilers */ 1351 1352 /* Here, scan <= window+strstart+257 */ 1353 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1354 if (*scan == *match) scan++; 1355 1356 len = (MAX_MATCH - 1) - (int)(strend-scan); 1357 scan = strend - (MAX_MATCH-1); 1358 1359#else /* UNALIGNED_OK */ 1360 1361 if (match[best_len] != scan_end || 1362 match[best_len-1] != scan_end1 || 1363 *match != *scan || 1364 *++match != scan[1]) continue; 1365 1366 /* The check at best_len-1 can be removed because it will be made 1367 * again later. (This heuristic is not always a win.) 1368 * It is not necessary to compare scan[2] and match[2] since they 1369 * are always equal when the other bytes match, given that 1370 * the hash keys are equal and that HASH_BITS >= 8. 1371 */ 1372 scan += 2, match++; 1373 Assert(*scan == *match, "match[2]?"); 1374 1375 /* We check for insufficient lookahead only every 8th comparison; 1376 * the 256th check will be made at strstart+258. 1377 */ 1378 do { 1379 } while (*++scan == *++match && *++scan == *++match && 1380 *++scan == *++match && *++scan == *++match && 1381 *++scan == *++match && *++scan == *++match && 1382 *++scan == *++match && *++scan == *++match && 1383 scan < strend); 1384 1385 Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan"); 1386 1387 len = MAX_MATCH - (int)(strend - scan); 1388 scan = strend - MAX_MATCH; 1389 1390#endif /* UNALIGNED_OK */ 1391 1392 if (len > best_len) { 1393 s->match_start = cur_match; 1394 best_len = len; 1395 if (len >= nice_match) break; 1396#ifdef UNALIGNED_OK 1397 scan_end = *(ushf*)(scan+best_len-1); 1398#else 1399 scan_end1 = scan[best_len-1]; 1400 scan_end = scan[best_len]; 1401#endif 1402 } 1403 } while ((cur_match = prev[cur_match & wmask]) > limit 1404 && --chain_length != 0); 1405 1406 if ((uInt)best_len <= s->lookahead) return best_len; 1407 return s->lookahead; 1408} 1409#endif /* ASMV */ 1410 1411#ifdef DEBUG_ZLIB 1412/* =========================================================================== 1413 * Check that the match at match_start is indeed a match. 1414 */ 1415local void check_match(s, start, match, length) 1416 deflate_state *s; 1417 IPos start, match; 1418 int length; 1419{ 1420 /* check that the match is indeed a match */ 1421 if (zmemcmp((charf *)s->window + match, 1422 (charf *)s->window + start, length) != EQUAL) { 1423 fprintf(stderr, " start %u, match %u, length %d\n", 1424 start, match, length); 1425 do { 1426 fprintf(stderr, "%c%c", s->window[match++], s->window[start++]); 1427 } while (--length != 0); 1428 z_error("invalid match"); 1429 } 1430 if (z_verbose > 1) { 1431 fprintf(stderr,"\\[%d,%d]", start-match, length); 1432 do { putc(s->window[start++], stderr); } while (--length != 0); 1433 } 1434} 1435#else 1436# define check_match(s, start, match, length) 1437#endif 1438 1439/* =========================================================================== 1440 * Fill the window when the lookahead becomes insufficient. 1441 * Updates strstart and lookahead. 1442 * 1443 * IN assertion: lookahead < MIN_LOOKAHEAD 1444 * OUT assertions: strstart <= window_size-MIN_LOOKAHEAD 1445 * At least one byte has been read, or avail_in == 0; reads are 1446 * performed for at least two bytes (required for the zip translate_eol 1447 * option -- not supported here). 1448 */ 1449local void fill_window(s) 1450 deflate_state *s; 1451{ 1452 register unsigned n, m; 1453 register Posf *p; 1454 unsigned more; /* Amount of free space at the end of the window. */ 1455 uInt wsize = s->w_size; 1456 1457 do { 1458 more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); 1459 1460 /* Deal with !@#$% 64K limit: */ 1461 if (more == 0 && s->strstart == 0 && s->lookahead == 0) { 1462 more = wsize; 1463 1464 } else if (more == (unsigned)(-1)) { 1465 /* Very unlikely, but possible on 16 bit machine if strstart == 0 1466 * and lookahead == 1 (input done one byte at time) 1467 */ 1468 more--; 1469 1470 /* If the window is almost full and there is insufficient lookahead, 1471 * move the upper half to the lower one to make room in the upper half. 1472 */ 1473 } else if (s->strstart >= wsize+MAX_DIST(s)) { 1474 1475 zmemcpy((charf *)s->window, (charf *)s->window+wsize, 1476 (unsigned)wsize); 1477 s->match_start -= wsize; 1478 s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ 1479 s->block_start -= (long) wsize; 1480 1481 /* Slide the hash table (could be avoided with 32 bit values 1482 at the expense of memory usage). We slide even when level == 0 1483 to keep the hash table consistent if we switch back to level > 0 1484 later. (Using level 0 permanently is not an optimal usage of 1485 zlib, so we don't care about this pathological case.) 1486 */ 1487 n = s->hash_size; 1488 p = &s->head[n]; 1489 do { 1490 m = *--p; 1491 *p = (Pos)(m >= wsize ? m-wsize : NIL); 1492 } while (--n); 1493 1494 n = wsize; 1495 p = &s->prev[n]; 1496 do { 1497 m = *--p; 1498 *p = (Pos)(m >= wsize ? m-wsize : NIL); 1499 /* If n is not on any hash chain, prev[n] is garbage but 1500 * its value will never be used. 1501 */ 1502 } while (--n); 1503 more += wsize; 1504 } 1505 if (s->strm->avail_in == 0) return; 1506 1507 /* If there was no sliding: 1508 * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && 1509 * more == window_size - lookahead - strstart 1510 * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) 1511 * => more >= window_size - 2*WSIZE + 2 1512 * In the BIG_MEM or MMAP case (not yet supported), 1513 * window_size == input_size + MIN_LOOKAHEAD && 1514 * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. 1515 * Otherwise, window_size == 2*WSIZE so more >= 2. 1516 * If there was sliding, more >= WSIZE. So in all cases, more >= 2. 1517 */ 1518 Assert(more >= 2, "more < 2"); 1519 1520 n = read_buf(s->strm, (charf *)s->window + s->strstart + s->lookahead, 1521 more); 1522 s->lookahead += n; 1523 1524 /* Initialize the hash value now that we have some input: */ 1525 if (s->lookahead >= MIN_MATCH) { 1526 s->ins_h = s->window[s->strstart]; 1527 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); 1528#if MIN_MATCH != 3 1529 Call UPDATE_HASH() MIN_MATCH-3 more times 1530#endif 1531 } 1532 /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, 1533 * but this is not important since only literal bytes will be emitted. 1534 */ 1535 1536 } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); 1537} 1538 1539/* =========================================================================== 1540 * Flush the current block, with given end-of-file flag. 1541 * IN assertion: strstart is set to the end of the current match. 1542 */ 1543#define FLUSH_BLOCK_ONLY(s, eof) { \ 1544 _tr_flush_block(s, (s->block_start >= 0L ? \ 1545 (charf *)&s->window[(unsigned)s->block_start] : \ 1546 (charf *)Z_NULL), \ 1547 (ulg)((long)s->strstart - s->block_start), \ 1548 (eof)); \ 1549 s->block_start = s->strstart; \ 1550 flush_pending(s->strm); \ 1551 Tracev((stderr,"[FLUSH]")); \ 1552} 1553 1554/* Same but force premature exit if necessary. */ 1555#define FLUSH_BLOCK(s, eof) { \ 1556 FLUSH_BLOCK_ONLY(s, eof); \ 1557 if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \ 1558} 1559 1560/* =========================================================================== 1561 * Copy without compression as much as possible from the input stream, return 1562 * the current block state. 1563 * This function does not insert new strings in the dictionary since 1564 * uncompressible data is probably not useful. This function is used 1565 * only for the level=0 compression option. 1566 * NOTE: this function should be optimized to avoid extra copying from 1567 * window to pending_buf. 1568 */ 1569local block_state deflate_stored(s, flush) 1570 deflate_state *s; 1571 int flush; 1572{ 1573 /* Stored blocks are limited to 0xffff bytes, pending_buf is limited 1574 * to pending_buf_size, and each stored block has a 5 byte header: 1575 */ 1576 ulg max_block_size = 0xffff; 1577 ulg max_start; 1578 1579 if (max_block_size > s->pending_buf_size - 5) { 1580 max_block_size = s->pending_buf_size - 5; 1581 } 1582 1583 /* Copy as much as possible from input to output: */ 1584 for (;;) { 1585 /* Fill the window as much as possible: */ 1586 if (s->lookahead <= 1) { 1587 1588 Assert(s->strstart < s->w_size+MAX_DIST(s) || 1589 s->block_start >= (long)s->w_size, "slide too late"); 1590 1591 fill_window(s); 1592 if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more; 1593 1594 if (s->lookahead == 0) break; /* flush the current block */ 1595 } 1596 Assert(s->block_start >= 0L, "block gone"); 1597 1598 s->strstart += s->lookahead; 1599 s->lookahead = 0; 1600 1601 /* Emit a stored block if pending_buf will be full: */ 1602 max_start = s->block_start + max_block_size; 1603 if (s->strstart == 0 || (ulg)s->strstart >= max_start) { 1604 /* strstart == 0 is possible when wraparound on 16-bit machine */ 1605 s->lookahead = (uInt)(s->strstart - max_start); 1606 s->strstart = (uInt)max_start; 1607 FLUSH_BLOCK(s, 0); 1608 } 1609 /* Flush if we may have to slide, otherwise block_start may become 1610 * negative and the data will be gone: 1611 */ 1612 if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) { 1613 FLUSH_BLOCK(s, 0); 1614 } 1615 } 1616 FLUSH_BLOCK(s, flush == Z_FINISH); 1617 return flush == Z_FINISH ? finish_done : block_done; 1618} 1619 1620/* =========================================================================== 1621 * Compress as much as possible from the input stream, return the current 1622 * block state. 1623 * This function does not perform lazy evaluation of matches and inserts 1624 * new strings in the dictionary only for unmatched strings or for short 1625 * matches. It is used only for the fast compression options. 1626 */ 1627local block_state deflate_fast(s, flush) 1628 deflate_state *s; 1629 int flush; 1630{ 1631 IPos hash_head = NIL; /* head of the hash chain */ 1632 int bflush; /* set if current block must be flushed */ 1633 1634 for (;;) { 1635 /* Make sure that we always have enough lookahead, except 1636 * at the end of the input file. We need MAX_MATCH bytes 1637 * for the next match, plus MIN_MATCH bytes to insert the 1638 * string following the next match. 1639 */ 1640 if (s->lookahead < MIN_LOOKAHEAD) { 1641 fill_window(s); 1642 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1643 return need_more; 1644 } 1645 if (s->lookahead == 0) break; /* flush the current block */ 1646 } 1647 1648 /* Insert the string window[strstart .. strstart+2] in the 1649 * dictionary, and set hash_head to the head of the hash chain: 1650 */ 1651 if (s->lookahead >= MIN_MATCH) { 1652 INSERT_STRING(s, s->strstart, hash_head); 1653 } 1654 1655 /* Find the longest match, discarding those <= prev_length. 1656 * At this point we have always match_length < MIN_MATCH 1657 */ 1658 if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) { 1659 /* To simplify the code, we prevent matches with the string 1660 * of window index 0 (in particular we have to avoid a match 1661 * of the string with itself at the start of the input file). 1662 */ 1663 if (s->strategy != Z_HUFFMAN_ONLY) { 1664 s->match_length = longest_match (s, hash_head); 1665 } 1666 /* longest_match() sets match_start */ 1667 } 1668 if (s->match_length >= MIN_MATCH) { 1669 check_match(s, s->strstart, s->match_start, s->match_length); 1670 1671 bflush = _tr_tally(s, s->strstart - s->match_start, 1672 s->match_length - MIN_MATCH); 1673 1674 s->lookahead -= s->match_length; 1675 1676 /* Insert new strings in the hash table only if the match length 1677 * is not too large. This saves time but degrades compression. 1678 */ 1679 if (s->match_length <= s->max_insert_length && 1680 s->lookahead >= MIN_MATCH) { 1681 s->match_length--; /* string at strstart already in hash table */ 1682 do { 1683 s->strstart++; 1684 INSERT_STRING(s, s->strstart, hash_head); 1685 /* strstart never exceeds WSIZE-MAX_MATCH, so there are 1686 * always MIN_MATCH bytes ahead. 1687 */ 1688 } while (--s->match_length != 0); 1689 s->strstart++; 1690 } else { 1691 s->strstart += s->match_length; 1692 s->match_length = 0; 1693 s->ins_h = s->window[s->strstart]; 1694 UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); 1695#if MIN_MATCH != 3 1696 Call UPDATE_HASH() MIN_MATCH-3 more times 1697#endif 1698 /* If lookahead < MIN_MATCH, ins_h is garbage, but it does not 1699 * matter since it will be recomputed at next deflate call. 1700 */ 1701 } 1702 } else { 1703 /* No match, output a literal byte */ 1704 Tracevv((stderr,"%c", s->window[s->strstart])); 1705 bflush = _tr_tally (s, 0, s->window[s->strstart]); 1706 s->lookahead--; 1707 s->strstart++; 1708 } 1709 if (bflush) FLUSH_BLOCK(s, 0); 1710 } 1711 FLUSH_BLOCK(s, flush == Z_FINISH); 1712 return flush == Z_FINISH ? finish_done : block_done; 1713} 1714 1715/* =========================================================================== 1716 * Same as above, but achieves better compression. We use a lazy 1717 * evaluation for matches: a match is finally adopted only if there is 1718 * no better match at the next window position. 1719 */ 1720local block_state deflate_slow(s, flush) 1721 deflate_state *s; 1722 int flush; 1723{ 1724 IPos hash_head = NIL; /* head of hash chain */ 1725 int bflush; /* set if current block must be flushed */ 1726 1727 /* Process the input block. */ 1728 for (;;) { 1729 /* Make sure that we always have enough lookahead, except 1730 * at the end of the input file. We need MAX_MATCH bytes 1731 * for the next match, plus MIN_MATCH bytes to insert the 1732 * string following the next match. 1733 */ 1734 if (s->lookahead < MIN_LOOKAHEAD) { 1735 fill_window(s); 1736 if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) { 1737 return need_more; 1738 } 1739 if (s->lookahead == 0) break; /* flush the current block */ 1740 } 1741 1742 /* Insert the string window[strstart .. strstart+2] in the 1743 * dictionary, and set hash_head to the head of the hash chain: 1744 */ 1745 if (s->lookahead >= MIN_MATCH) { 1746 INSERT_STRING(s, s->strstart, hash_head); 1747 } 1748 1749 /* Find the longest match, discarding those <= prev_length. 1750 */ 1751 s->prev_length = s->match_length, s->prev_match = s->match_start; 1752 s->match_length = MIN_MATCH-1; 1753 1754 if (hash_head != NIL && s->prev_length < s->max_lazy_match && 1755 s->strstart - hash_head <= MAX_DIST(s)) { 1756 /* To simplify the code, we prevent matches with the string 1757 * of window index 0 (in particular we have to avoid a match 1758 * of the string with itself at the start of the input file). 1759 */ 1760 if (s->strategy != Z_HUFFMAN_ONLY) { 1761 s->match_length = longest_match (s, hash_head); 1762 } 1763 /* longest_match() sets match_start */ 1764 1765 if (s->match_length <= 5 && (s->strategy == Z_FILTERED || 1766 (s->match_length == MIN_MATCH && 1767 s->strstart - s->match_start > TOO_FAR))) { 1768 1769 /* If prev_match is also MIN_MATCH, match_start is garbage 1770 * but we will ignore the current match anyway. 1771 */ 1772 s->match_length = MIN_MATCH-1; 1773 } 1774 } 1775 /* If there was a match at the previous step and the current 1776 * match is not better, output the previous match: 1777 */ 1778 if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) { 1779 uInt max_insert = s->strstart + s->lookahead - MIN_MATCH; 1780 /* Do not insert strings in hash table beyond this. */ 1781 1782 check_match(s, s->strstart-1, s->prev_match, s->prev_length); 1783 1784 bflush = _tr_tally(s, s->strstart -1 - s->prev_match, 1785 s->prev_length - MIN_MATCH); 1786 1787 /* Insert in hash table all strings up to the end of the match. 1788 * strstart-1 and strstart are already inserted. If there is not 1789 * enough lookahead, the last two strings are not inserted in 1790 * the hash table. 1791 */ 1792 s->lookahead -= s->prev_length-1; 1793 s->prev_length -= 2; 1794 do { 1795 if (++s->strstart <= max_insert) { 1796 INSERT_STRING(s, s->strstart, hash_head); 1797 } 1798 } while (--s->prev_length != 0); 1799 s->match_available = 0; 1800 s->match_length = MIN_MATCH-1; 1801 s->strstart++; 1802 1803 if (bflush) FLUSH_BLOCK(s, 0); 1804 1805 } else if (s->match_available) { 1806 /* If there was no match at the previous position, output a 1807 * single literal. If there was a match but the current match 1808 * is longer, truncate the previous match to a single literal. 1809 */ 1810 Tracevv((stderr,"%c", s->window[s->strstart-1])); 1811 if (_tr_tally (s, 0, s->window[s->strstart-1])) { 1812 FLUSH_BLOCK_ONLY(s, 0); 1813 } 1814 s->strstart++; 1815 s->lookahead--; 1816 if (s->strm->avail_out == 0) return need_more; 1817 } else { 1818 /* There is no previous match to compare with, wait for 1819 * the next step to decide. 1820 */ 1821 s->match_available = 1; 1822 s->strstart++; 1823 s->lookahead--; 1824 } 1825 } 1826 Assert (flush != Z_NO_FLUSH, "no flush?"); 1827 if (s->match_available) { 1828 Tracevv((stderr,"%c", s->window[s->strstart-1])); 1829 _tr_tally (s, 0, s->window[s->strstart-1]); 1830 s->match_available = 0; 1831 } 1832 FLUSH_BLOCK(s, flush == Z_FINISH); 1833 return flush == Z_FINISH ? finish_done : block_done; 1834} 1835/* --- deflate.c */ 1836 1837/* +++ trees.c */ 1838/* trees.c -- output deflated data using Huffman coding 1839 * Copyright (C) 1995-1996 Jean-loup Gailly 1840 * For conditions of distribution and use, see copyright notice in zlib.h 1841 */ 1842 1843/* 1844 * ALGORITHM 1845 * 1846 * The "deflation" process uses several Huffman trees. The more 1847 * common source values are represented by shorter bit sequences. 1848 * 1849 * Each code tree is stored in a compressed form which is itself 1850 * a Huffman encoding of the lengths of all the code strings (in 1851 * ascending order by source values). The actual code strings are 1852 * reconstructed from the lengths in the inflate process, as described 1853 * in the deflate specification. 1854 * 1855 * REFERENCES 1856 * 1857 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". 1858 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc 1859 * 1860 * Storer, James A. 1861 * Data Compression: Methods and Theory, pp. 49-50. 1862 * Computer Science Press, 1988. ISBN 0-7167-8156-5. 1863 * 1864 * Sedgewick, R. 1865 * Algorithms, p290. 1866 * Addison-Wesley, 1983. ISBN 0-201-06672-6. 1867 */ 1868 1869/* From: trees.c,v 1.11 1996/07/24 13:41:06 me Exp $ */ 1870 1871/* #include "deflate.h" */ 1872 1873#ifdef DEBUG_ZLIB 1874# include <ctype.h> 1875#endif 1876 1877/* =========================================================================== 1878 * Constants 1879 */ 1880 1881#define MAX_BL_BITS 7 1882/* Bit length codes must not exceed MAX_BL_BITS bits */ 1883 1884#define END_BLOCK 256 1885/* end of block literal code */ 1886 1887#define REP_3_6 16 1888/* repeat previous bit length 3-6 times (2 bits of repeat count) */ 1889 1890#define REPZ_3_10 17 1891/* repeat a zero length 3-10 times (3 bits of repeat count) */ 1892 1893#define REPZ_11_138 18 1894/* repeat a zero length 11-138 times (7 bits of repeat count) */ 1895 1896local int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ 1897 = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0}; 1898 1899local int extra_dbits[D_CODES] /* extra bits for each distance code */ 1900 = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13}; 1901 1902local int extra_blbits[BL_CODES]/* extra bits for each bit length code */ 1903 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; 1904 1905local uch bl_order[BL_CODES] 1906 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; 1907/* The lengths of the bit length codes are sent in order of decreasing 1908 * probability, to avoid transmitting the lengths for unused bit length codes. 1909 */ 1910 1911#define Buf_size (8 * 2*sizeof(char)) 1912/* Number of bits used within bi_buf. (bi_buf might be implemented on 1913 * more than 16 bits on some systems.) 1914 */ 1915 1916/* =========================================================================== 1917 * Local data. These are initialized only once. 1918 */ 1919 1920local ct_data static_ltree[L_CODES+2]; 1921/* The static literal tree. Since the bit lengths are imposed, there is no 1922 * need for the L_CODES extra codes used during heap construction. However 1923 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init 1924 * below). 1925 */ 1926 1927local ct_data static_dtree[D_CODES]; 1928/* The static distance tree. (Actually a trivial tree since all codes use 1929 * 5 bits.) 1930 */ 1931 1932local uch dist_code[512]; 1933/* distance codes. The first 256 values correspond to the distances 1934 * 3 .. 258, the last 256 values correspond to the top 8 bits of 1935 * the 15 bit distances. 1936 */ 1937 1938local uch length_code[MAX_MATCH-MIN_MATCH+1]; 1939/* length code for each normalized match length (0 == MIN_MATCH) */ 1940 1941local int base_length[LENGTH_CODES]; 1942/* First normalized length for each code (0 = MIN_MATCH) */ 1943 1944local int base_dist[D_CODES]; 1945/* First normalized distance for each code (0 = distance of 1) */ 1946 1947struct static_tree_desc_s { 1948 ct_data *static_tree; /* static tree or NULL */ 1949 intf *extra_bits; /* extra bits for each code or NULL */ 1950 int extra_base; /* base index for extra_bits */ 1951 int elems; /* max number of elements in the tree */ 1952 int max_length; /* max bit length for the codes */ 1953}; 1954 1955local static_tree_desc static_l_desc = 1956{static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; 1957 1958local static_tree_desc static_d_desc = 1959{static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; 1960 1961local static_tree_desc static_bl_desc = 1962{(ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; 1963 1964/* =========================================================================== 1965 * Local (static) routines in this file. 1966 */ 1967 1968local void tr_static_init OF((void)); 1969local void init_block OF((deflate_state *s)); 1970local void pqdownheap OF((deflate_state *s, ct_data *tree, int k)); 1971local void gen_bitlen OF((deflate_state *s, tree_desc *desc)); 1972local void gen_codes OF((ct_data *tree, int max_code, ushf *bl_count)); 1973local void build_tree OF((deflate_state *s, tree_desc *desc)); 1974local void scan_tree OF((deflate_state *s, ct_data *tree, int max_code)); 1975local void send_tree OF((deflate_state *s, ct_data *tree, int max_code)); 1976local int build_bl_tree OF((deflate_state *s)); 1977local void send_all_trees OF((deflate_state *s, int lcodes, int dcodes, 1978 int blcodes)); 1979local void compress_block OF((deflate_state *s, ct_data *ltree, 1980 ct_data *dtree)); 1981local void set_data_type OF((deflate_state *s)); 1982local unsigned bi_reverse OF((unsigned value, int length)); 1983local void bi_windup OF((deflate_state *s)); 1984local void bi_flush OF((deflate_state *s)); 1985local void copy_block OF((deflate_state *s, charf *buf, unsigned len, 1986 int header)); 1987 1988#ifndef DEBUG_ZLIB 1989# define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) 1990 /* Send a code of the given tree. c and tree must not have side effects */ 1991 1992#else /* DEBUG_ZLIB */ 1993# define send_code(s, c, tree) \ 1994 { if (verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ 1995 send_bits(s, tree[c].Code, tree[c].Len); } 1996#endif 1997 1998#define d_code(dist) \ 1999 ((dist) < 256 ? dist_code[dist] : dist_code[256+((dist)>>7)]) 2000/* Mapping from a distance to a distance code. dist is the distance - 1 and 2001 * must not have side effects. dist_code[256] and dist_code[257] are never 2002 * used. 2003 */ 2004 2005/* =========================================================================== 2006 * Output a short LSB first on the stream. 2007 * IN assertion: there is enough room in pendingBuf. 2008 */ 2009#define put_short(s, w) { \ 2010 put_byte(s, (uch)((w) & 0xff)); \ 2011 put_byte(s, (uch)((ush)(w) >> 8)); \ 2012} 2013 2014/* =========================================================================== 2015 * Send a value on a given number of bits. 2016 * IN assertion: length <= 16 and value fits in length bits. 2017 */ 2018#ifdef DEBUG_ZLIB 2019local void send_bits OF((deflate_state *s, int value, int length)); 2020 2021local void send_bits(s, value, length) 2022 deflate_state *s; 2023 int value; /* value to send */ 2024 int length; /* number of bits */ 2025{ 2026 Tracevv((stderr," l %2d v %4x ", length, value)); 2027 Assert(length > 0 && length <= 15, "invalid length"); 2028 s->bits_sent += (ulg)length; 2029 2030 /* If not enough room in bi_buf, use (valid) bits from bi_buf and 2031 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) 2032 * unused bits in value. 2033 */ 2034 if (s->bi_valid > (int)Buf_size - length) { 2035 s->bi_buf |= (value << s->bi_valid); 2036 put_short(s, s->bi_buf); 2037 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); 2038 s->bi_valid += length - Buf_size; 2039 } else { 2040 s->bi_buf |= value << s->bi_valid; 2041 s->bi_valid += length; 2042 } 2043} 2044#else /* !DEBUG_ZLIB */ 2045 2046#define send_bits(s, value, length) \ 2047{ int len = length;\ 2048 if (s->bi_valid > (int)Buf_size - len) {\ 2049 int val = value;\ 2050 s->bi_buf |= (val << s->bi_valid);\ 2051 put_short(s, s->bi_buf);\ 2052 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ 2053 s->bi_valid += len - Buf_size;\ 2054 } else {\ 2055 s->bi_buf |= (value) << s->bi_valid;\ 2056 s->bi_valid += len;\ 2057 }\ 2058} 2059#endif /* DEBUG_ZLIB */ 2060 2061 2062#define MAX(a,b) (a >= b ? a : b) 2063/* the arguments must not have side effects */ 2064 2065/* =========================================================================== 2066 * Initialize the various 'constant' tables. In a multi-threaded environment, 2067 * this function may be called by two threads concurrently, but this is 2068 * harmless since both invocations do exactly the same thing. 2069 */ 2070local void tr_static_init() 2071{ 2072 static int static_init_done = 0; 2073 int n; /* iterates over tree elements */ 2074 int bits; /* bit counter */ 2075 int length; /* length value */ 2076 int code; /* code value */ 2077 int dist; /* distance index */ 2078 ush bl_count[MAX_BITS+1]; 2079 /* number of codes at each bit length for an optimal tree */ 2080 2081 if (static_init_done) return; 2082 2083 /* Initialize the mapping length (0..255) -> length code (0..28) */ 2084 length = 0; 2085 for (code = 0; code < LENGTH_CODES-1; code++) { 2086 base_length[code] = length; 2087 for (n = 0; n < (1<<extra_lbits[code]); n++) { 2088 length_code[length++] = (uch)code; 2089 } 2090 } 2091 Assert (length == 256, "tr_static_init: length != 256"); 2092 /* Note that the length 255 (match length 258) can be represented 2093 * in two different ways: code 284 + 5 bits or code 285, so we 2094 * overwrite length_code[255] to use the best encoding: 2095 */ 2096 length_code[length-1] = (uch)code; 2097 2098 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ 2099 dist = 0; 2100 for (code = 0 ; code < 16; code++) { 2101 base_dist[code] = dist; 2102 for (n = 0; n < (1<<extra_dbits[code]); n++) { 2103 dist_code[dist++] = (uch)code; 2104 } 2105 } 2106 Assert (dist == 256, "tr_static_init: dist != 256"); 2107 dist >>= 7; /* from now on, all distances are divided by 128 */ 2108 for ( ; code < D_CODES; code++) { 2109 base_dist[code] = dist << 7; 2110 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { 2111 dist_code[256 + dist++] = (uch)code; 2112 } 2113 } 2114 Assert (dist == 256, "tr_static_init: 256+dist != 512"); 2115 2116 /* Construct the codes of the static literal tree */ 2117 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; 2118 n = 0; 2119 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; 2120 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; 2121 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; 2122 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; 2123 /* Codes 286 and 287 do not exist, but we must include them in the 2124 * tree construction to get a canonical Huffman tree (longest code 2125 * all ones) 2126 */ 2127 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); 2128 2129 /* The static distance tree is trivial: */ 2130 for (n = 0; n < D_CODES; n++) { 2131 static_dtree[n].Len = 5; 2132 static_dtree[n].Code = bi_reverse((unsigned)n, 5); 2133 } 2134 static_init_done = 1; 2135} 2136 2137/* =========================================================================== 2138 * Initialize the tree data structures for a new zlib stream. 2139 */ 2140void _tr_init(s) 2141 deflate_state *s; 2142{ 2143 tr_static_init(); 2144 2145 s->compressed_len = 0L; 2146 2147 s->l_desc.dyn_tree = s->dyn_ltree; 2148 s->l_desc.stat_desc = &static_l_desc; 2149 2150 s->d_desc.dyn_tree = s->dyn_dtree; 2151 s->d_desc.stat_desc = &static_d_desc; 2152 2153 s->bl_desc.dyn_tree = s->bl_tree; 2154 s->bl_desc.stat_desc = &static_bl_desc; 2155 2156 s->bi_buf = 0; 2157 s->bi_valid = 0; 2158 s->last_eob_len = 8; /* enough lookahead for inflate */ 2159#ifdef DEBUG_ZLIB 2160 s->bits_sent = 0L; 2161#endif 2162 2163 /* Initialize the first block of the first file: */ 2164 init_block(s); 2165} 2166 2167/* =========================================================================== 2168 * Initialize a new block. 2169 */ 2170local void init_block(s) 2171 deflate_state *s; 2172{ 2173 int n; /* iterates over tree elements */ 2174 2175 /* Initialize the trees. */ 2176 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; 2177 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; 2178 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; 2179 2180 s->dyn_ltree[END_BLOCK].Freq = 1; 2181 s->opt_len = s->static_len = 0L; 2182 s->last_lit = s->matches = 0; 2183} 2184 2185#define SMALLEST 1 2186/* Index within the heap array of least frequent node in the Huffman tree */ 2187 2188 2189/* =========================================================================== 2190 * Remove the smallest element from the heap and recreate the heap with 2191 * one less element. Updates heap and heap_len. 2192 */ 2193#define pqremove(s, tree, top) \ 2194{\ 2195 top = s->heap[SMALLEST]; \ 2196 s->heap[SMALLEST] = s->heap[s->heap_len--]; \ 2197 pqdownheap(s, tree, SMALLEST); \ 2198} 2199 2200/* =========================================================================== 2201 * Compares to subtrees, using the tree depth as tie breaker when 2202 * the subtrees have equal frequency. This minimizes the worst case length. 2203 */ 2204#define smaller(tree, n, m, depth) \ 2205 (tree[n].Freq < tree[m].Freq || \ 2206 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) 2207 2208/* =========================================================================== 2209 * Restore the heap property by moving down the tree starting at node k, 2210 * exchanging a node with the smallest of its two sons if necessary, stopping 2211 * when the heap property is re-established (each father smaller than its 2212 * two sons). 2213 */ 2214local void pqdownheap(s, tree, k) 2215 deflate_state *s; 2216 ct_data *tree; /* the tree to restore */ 2217 int k; /* node to move down */ 2218{ 2219 int v = s->heap[k]; 2220 int j = k << 1; /* left son of k */ 2221 while (j <= s->heap_len) { 2222 /* Set j to the smallest of the two sons: */ 2223 if (j < s->heap_len && 2224 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { 2225 j++; 2226 } 2227 /* Exit if v is smaller than both sons */ 2228 if (smaller(tree, v, s->heap[j], s->depth)) break; 2229 2230 /* Exchange v with the smallest son */ 2231 s->heap[k] = s->heap[j]; k = j; 2232 2233 /* And continue down the tree, setting j to the left son of k */ 2234 j <<= 1; 2235 } 2236 s->heap[k] = v; 2237} 2238 2239/* =========================================================================== 2240 * Compute the optimal bit lengths for a tree and update the total bit length 2241 * for the current block. 2242 * IN assertion: the fields freq and dad are set, heap[heap_max] and 2243 * above are the tree nodes sorted by increasing frequency. 2244 * OUT assertions: the field len is set to the optimal bit length, the 2245 * array bl_count contains the frequencies for each bit length. 2246 * The length opt_len is updated; static_len is also updated if stree is 2247 * not null. 2248 */ 2249local void gen_bitlen(s, desc) 2250 deflate_state *s; 2251 tree_desc *desc; /* the tree descriptor */ 2252{ 2253 ct_data *tree = desc->dyn_tree; 2254 int max_code = desc->max_code; 2255 ct_data *stree = desc->stat_desc->static_tree; 2256 intf *extra = desc->stat_desc->extra_bits; 2257 int base = desc->stat_desc->extra_base; 2258 int max_length = desc->stat_desc->max_length; 2259 int h; /* heap index */ 2260 int n, m; /* iterate over the tree elements */ 2261 int bits; /* bit length */ 2262 int xbits; /* extra bits */ 2263 ush f; /* frequency */ 2264 int overflow = 0; /* number of elements with bit length too large */ 2265 2266 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; 2267 2268 /* In a first pass, compute the optimal bit lengths (which may 2269 * overflow in the case of the bit length tree). 2270 */ 2271 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ 2272 2273 for (h = s->heap_max+1; h < HEAP_SIZE; h++) { 2274 n = s->heap[h]; 2275 bits = tree[tree[n].Dad].Len + 1; 2276 if (bits > max_length) bits = max_length, overflow++; 2277 tree[n].Len = (ush)bits; 2278 /* We overwrite tree[n].Dad which is no longer needed */ 2279 2280 if (n > max_code) continue; /* not a leaf node */ 2281 2282 s->bl_count[bits]++; 2283 xbits = 0; 2284 if (n >= base) xbits = extra[n-base]; 2285 f = tree[n].Freq; 2286 s->opt_len += (ulg)f * (bits + xbits); 2287 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); 2288 } 2289 if (overflow == 0) return; 2290 2291 Trace((stderr,"\nbit length overflow\n")); 2292 /* This happens for example on obj2 and pic of the Calgary corpus */ 2293 2294 /* Find the first bit length which could increase: */ 2295 do { 2296 bits = max_length-1; 2297 while (s->bl_count[bits] == 0) bits--; 2298 s->bl_count[bits]--; /* move one leaf down the tree */ 2299 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ 2300 s->bl_count[max_length]--; 2301 /* The brother of the overflow item also moves one step up, 2302 * but this does not affect bl_count[max_length] 2303 */ 2304 overflow -= 2; 2305 } while (overflow > 0); 2306 2307 /* Now recompute all bit lengths, scanning in increasing frequency. 2308 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all 2309 * lengths instead of fixing only the wrong ones. This idea is taken 2310 * from 'ar' written by Haruhiko Okumura.) 2311 */ 2312 for (bits = max_length; bits != 0; bits--) { 2313 n = s->bl_count[bits]; 2314 while (n != 0) { 2315 m = s->heap[--h]; 2316 if (m > max_code) continue; 2317 if (tree[m].Len != (unsigned) bits) { 2318 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); 2319 s->opt_len += ((long)bits - (long)tree[m].Len) 2320 *(long)tree[m].Freq; 2321 tree[m].Len = (ush)bits; 2322 } 2323 n--; 2324 } 2325 } 2326} 2327 2328/* =========================================================================== 2329 * Generate the codes for a given tree and bit counts (which need not be 2330 * optimal). 2331 * IN assertion: the array bl_count contains the bit length statistics for 2332 * the given tree and the field len is set for all tree elements. 2333 * OUT assertion: the field code is set for all tree elements of non 2334 * zero code length. 2335 */ 2336local void gen_codes (tree, max_code, bl_count) 2337 ct_data *tree; /* the tree to decorate */ 2338 int max_code; /* largest code with non zero frequency */ 2339 ushf *bl_count; /* number of codes at each bit length */ 2340{ 2341 ush next_code[MAX_BITS+1]; /* next code value for each bit length */ 2342 ush code = 0; /* running code value */ 2343 int bits; /* bit index */ 2344 int n; /* code index */ 2345 2346 /* The distribution counts are first used to generate the code values 2347 * without bit reversal. 2348 */ 2349 for (bits = 1; bits <= MAX_BITS; bits++) { 2350 next_code[bits] = code = (code + bl_count[bits-1]) << 1; 2351 } 2352 /* Check that the bit counts in bl_count are consistent. The last code 2353 * must be all ones. 2354 */ 2355 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, 2356 "inconsistent bit counts"); 2357 Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); 2358 2359 for (n = 0; n <= max_code; n++) { 2360 int len = tree[n].Len; 2361 if (len == 0) continue; 2362 /* Now reverse the bits */ 2363 tree[n].Code = bi_reverse(next_code[len]++, len); 2364 2365 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", 2366 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); 2367 } 2368} 2369 2370/* =========================================================================== 2371 * Construct one Huffman tree and assigns the code bit strings and lengths. 2372 * Update the total bit length for the current block. 2373 * IN assertion: the field freq is set for all tree elements. 2374 * OUT assertions: the fields len and code are set to the optimal bit length 2375 * and corresponding code. The length opt_len is updated; static_len is 2376 * also updated if stree is not null. The field max_code is set. 2377 */ 2378local void build_tree(s, desc) 2379 deflate_state *s; 2380 tree_desc *desc; /* the tree descriptor */ 2381{ 2382 ct_data *tree = desc->dyn_tree; 2383 ct_data *stree = desc->stat_desc->static_tree; 2384 int elems = desc->stat_desc->elems; 2385 int n, m; /* iterate over heap elements */ 2386 int max_code = -1; /* largest code with non zero frequency */ 2387 int node; /* new node being created */ 2388 2389 /* Construct the initial heap, with least frequent element in 2390 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. 2391 * heap[0] is not used. 2392 */ 2393 s->heap_len = 0, s->heap_max = HEAP_SIZE; 2394 2395 for (n = 0; n < elems; n++) { 2396 if (tree[n].Freq != 0) { 2397 s->heap[++(s->heap_len)] = max_code = n; 2398 s->depth[n] = 0; 2399 } else { 2400 tree[n].Len = 0; 2401 } 2402 } 2403 2404 /* The pkzip format requires that at least one distance code exists, 2405 * and that at least one bit should be sent even if there is only one 2406 * possible code. So to avoid special checks later on we force at least 2407 * two codes of non zero frequency. 2408 */ 2409 while (s->heap_len < 2) { 2410 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); 2411 tree[node].Freq = 1; 2412 s->depth[node] = 0; 2413 s->opt_len--; if (stree) s->static_len -= stree[node].Len; 2414 /* node is 0 or 1 so it does not have extra bits */ 2415 } 2416 desc->max_code = max_code; 2417 2418 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, 2419 * establish sub-heaps of increasing lengths: 2420 */ 2421 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); 2422 2423 /* Construct the Huffman tree by repeatedly combining the least two 2424 * frequent nodes. 2425 */ 2426 node = elems; /* next internal node of the tree */ 2427 do { 2428 pqremove(s, tree, n); /* n = node of least frequency */ 2429 m = s->heap[SMALLEST]; /* m = node of next least frequency */ 2430 2431 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ 2432 s->heap[--(s->heap_max)] = m; 2433 2434 /* Create a new node father of n and m */ 2435 tree[node].Freq = tree[n].Freq + tree[m].Freq; 2436 s->depth[node] = (uch) (MAX(s->depth[n], s->depth[m]) + 1); 2437 tree[n].Dad = tree[m].Dad = (ush)node; 2438#ifdef DUMP_BL_TREE 2439 if (tree == s->bl_tree) { 2440 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", 2441 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); 2442 } 2443#endif 2444 /* and insert the new node in the heap */ 2445 s->heap[SMALLEST] = node++; 2446 pqdownheap(s, tree, SMALLEST); 2447 2448 } while (s->heap_len >= 2); 2449 2450 s->heap[--(s->heap_max)] = s->heap[SMALLEST]; 2451 2452 /* At this point, the fields freq and dad are set. We can now 2453 * generate the bit lengths. 2454 */ 2455 gen_bitlen(s, (tree_desc *)desc); 2456 2457 /* The field len is now set, we can generate the bit codes */ 2458 gen_codes ((ct_data *)tree, max_code, s->bl_count); 2459} 2460 2461/* =========================================================================== 2462 * Scan a literal or distance tree to determine the frequencies of the codes 2463 * in the bit length tree. 2464 */ 2465local void scan_tree (s, tree, max_code) 2466 deflate_state *s; 2467 ct_data *tree; /* the tree to be scanned */ 2468 int max_code; /* and its largest code of non zero frequency */ 2469{ 2470 int n; /* iterates over all tree elements */ 2471 int prevlen = -1; /* last emitted length */ 2472 int curlen; /* length of current code */ 2473 int nextlen = tree[0].Len; /* length of next code */ 2474 int count = 0; /* repeat count of the current code */ 2475 int max_count = 7; /* max repeat count */ 2476 int min_count = 4; /* min repeat count */ 2477 2478 if (nextlen == 0) max_count = 138, min_count = 3; 2479 tree[max_code+1].Len = (ush)0xffff; /* guard */ 2480 2481 for (n = 0; n <= max_code; n++) { 2482 curlen = nextlen; nextlen = tree[n+1].Len; 2483 if (++count < max_count && curlen == nextlen) { 2484 continue; 2485 } else if (count < min_count) { 2486 s->bl_tree[curlen].Freq += count; 2487 } else if (curlen != 0) { 2488 if (curlen != prevlen) s->bl_tree[curlen].Freq++; 2489 s->bl_tree[REP_3_6].Freq++; 2490 } else if (count <= 10) { 2491 s->bl_tree[REPZ_3_10].Freq++; 2492 } else { 2493 s->bl_tree[REPZ_11_138].Freq++; 2494 } 2495 count = 0; prevlen = curlen; 2496 if (nextlen == 0) { 2497 max_count = 138, min_count = 3; 2498 } else if (curlen == nextlen) { 2499 max_count = 6, min_count = 3; 2500 } else { 2501 max_count = 7, min_count = 4; 2502 } 2503 } 2504} 2505 2506/* =========================================================================== 2507 * Send a literal or distance tree in compressed form, using the codes in 2508 * bl_tree. 2509 */ 2510local void send_tree (s, tree, max_code) 2511 deflate_state *s; 2512 ct_data *tree; /* the tree to be scanned */ 2513 int max_code; /* and its largest code of non zero frequency */ 2514{ 2515 int n; /* iterates over all tree elements */ 2516 int prevlen = -1; /* last emitted length */ 2517 int curlen; /* length of current code */ 2518 int nextlen = tree[0].Len; /* length of next code */ 2519 int count = 0; /* repeat count of the current code */ 2520 int max_count = 7; /* max repeat count */ 2521 int min_count = 4; /* min repeat count */ 2522 2523 /* tree[max_code+1].Len = -1; */ /* guard already set */ 2524 if (nextlen == 0) max_count = 138, min_count = 3; 2525 2526 for (n = 0; n <= max_code; n++) { 2527 curlen = nextlen; nextlen = tree[n+1].Len; 2528 if (++count < max_count && curlen == nextlen) { 2529 continue; 2530 } else if (count < min_count) { 2531 do { send_code(s, curlen, s->bl_tree); } while (--count != 0); 2532 2533 } else if (curlen != 0) { 2534 if (curlen != prevlen) { 2535 send_code(s, curlen, s->bl_tree); count--; 2536 } 2537 Assert(count >= 3 && count <= 6, " 3_6?"); 2538 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); 2539 2540 } else if (count <= 10) { 2541 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); 2542 2543 } else { 2544 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); 2545 } 2546 count = 0; prevlen = curlen; 2547 if (nextlen == 0) { 2548 max_count = 138, min_count = 3; 2549 } else if (curlen == nextlen) { 2550 max_count = 6, min_count = 3; 2551 } else { 2552 max_count = 7, min_count = 4; 2553 } 2554 } 2555} 2556 2557/* =========================================================================== 2558 * Construct the Huffman tree for the bit lengths and return the index in 2559 * bl_order of the last bit length code to send. 2560 */ 2561local int build_bl_tree(s) 2562 deflate_state *s; 2563{ 2564 int max_blindex; /* index of last bit length code of non zero freq */ 2565 2566 /* Determine the bit length frequencies for literal and distance trees */ 2567 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); 2568 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); 2569 2570 /* Build the bit length tree: */ 2571 build_tree(s, (tree_desc *)(&(s->bl_desc))); 2572 /* opt_len now includes the length of the tree representations, except 2573 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. 2574 */ 2575 2576 /* Determine the number of bit length codes to send. The pkzip format 2577 * requires that at least 4 bit length codes be sent. (appnote.txt says 2578 * 3 but the actual value used is 4.) 2579 */ 2580 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { 2581 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; 2582 } 2583 /* Update opt_len to include the bit length tree and counts */ 2584 s->opt_len += 3*(max_blindex+1) + 5+5+4; 2585 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", 2586 s->opt_len, s->static_len)); 2587 2588 return max_blindex; 2589} 2590 2591/* =========================================================================== 2592 * Send the header for a block using dynamic Huffman trees: the counts, the 2593 * lengths of the bit length codes, the literal tree and the distance tree. 2594 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. 2595 */ 2596local void send_all_trees(s, lcodes, dcodes, blcodes) 2597 deflate_state *s; 2598 int lcodes, dcodes, blcodes; /* number of codes for each tree */ 2599{ 2600 int rank; /* index in bl_order */ 2601 2602 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); 2603 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, 2604 "too many codes"); 2605 Tracev((stderr, "\nbl counts: ")); 2606 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ 2607 send_bits(s, dcodes-1, 5); 2608 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ 2609 for (rank = 0; rank < blcodes; rank++) { 2610 Tracev((stderr, "\nbl code %2d ", bl_order[rank])); 2611 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); 2612 } 2613 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); 2614 2615 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ 2616 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); 2617 2618 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ 2619 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); 2620} 2621 2622/* =========================================================================== 2623 * Send a stored block 2624 */ 2625void _tr_stored_block(s, buf, stored_len, eof) 2626 deflate_state *s; 2627 charf *buf; /* input block */ 2628 ulg stored_len; /* length of input block */ 2629 int eof; /* true if this is the last block for a file */ 2630{ 2631 send_bits(s, (STORED_BLOCK<<1)+eof, 3); /* send block type */ 2632 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; 2633 s->compressed_len += (stored_len + 4) << 3; 2634 2635 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ 2636} 2637 2638/* Send just the `stored block' type code without any length bytes or data. 2639 */ 2640void _tr_stored_type_only(s) 2641 deflate_state *s; 2642{ 2643 send_bits(s, (STORED_BLOCK << 1), 3); 2644 bi_windup(s); 2645 s->compressed_len = (s->compressed_len + 3) & ~7L; 2646} 2647 2648 2649/* =========================================================================== 2650 * Send one empty static block to give enough lookahead for inflate. 2651 * This takes 10 bits, of which 7 may remain in the bit buffer. 2652 * The current inflate code requires 9 bits of lookahead. If the 2653 * last two codes for the previous block (real code plus EOB) were coded 2654 * on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode 2655 * the last real code. In this case we send two empty static blocks instead 2656 * of one. (There are no problems if the previous block is stored or fixed.) 2657 * To simplify the code, we assume the worst case of last real code encoded 2658 * on one bit only. 2659 */ 2660void _tr_align(s) 2661 deflate_state *s; 2662{ 2663 send_bits(s, STATIC_TREES<<1, 3); 2664 send_code(s, END_BLOCK, static_ltree); 2665 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ 2666 bi_flush(s); 2667 /* Of the 10 bits for the empty block, we have already sent 2668 * (10 - bi_valid) bits. The lookahead for the last real code (before 2669 * the EOB of the previous block) was thus at least one plus the length 2670 * of the EOB plus what we have just sent of the empty static block. 2671 */ 2672 if (1 + s->last_eob_len + 10 - s->bi_valid < 9) { 2673 send_bits(s, STATIC_TREES<<1, 3); 2674 send_code(s, END_BLOCK, static_ltree); 2675 s->compressed_len += 10L; 2676 bi_flush(s); 2677 } 2678 s->last_eob_len = 7; 2679} 2680 2681/* =========================================================================== 2682 * Determine the best encoding for the current block: dynamic trees, static 2683 * trees or store, and output the encoded block to the zip file. This function 2684 * returns the total compressed length for the file so far. 2685 */ 2686ulg _tr_flush_block(s, buf, stored_len, eof) 2687 deflate_state *s; 2688 charf *buf; /* input block, or NULL if too old */ 2689 ulg stored_len; /* length of input block */ 2690 int eof; /* true if this is the last block for a file */ 2691{ 2692 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ 2693 int max_blindex = 0; /* index of last bit length code of non zero freq */ 2694 2695 /* Build the Huffman trees unless a stored block is forced */ 2696 if (s->level > 0) { 2697 2698 /* Check if the file is ascii or binary */ 2699 if (s->data_type == Z_UNKNOWN) set_data_type(s); 2700 2701 /* Construct the literal and distance trees */ 2702 build_tree(s, (tree_desc *)(&(s->l_desc))); 2703 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, 2704 s->static_len)); 2705 2706 build_tree(s, (tree_desc *)(&(s->d_desc))); 2707 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, 2708 s->static_len)); 2709 /* At this point, opt_len and static_len are the total bit lengths of 2710 * the compressed block data, excluding the tree representations. 2711 */ 2712 2713 /* Build the bit length tree for the above two trees, and get the index 2714 * in bl_order of the last bit length code to send. 2715 */ 2716 max_blindex = build_bl_tree(s); 2717 2718 /* Determine the best encoding. Compute first the block length in bytes*/ 2719 opt_lenb = (s->opt_len+3+7)>>3; 2720 static_lenb = (s->static_len+3+7)>>3; 2721 2722 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", 2723 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, 2724 s->last_lit)); 2725 2726 if (static_lenb <= opt_lenb) opt_lenb = static_lenb; 2727 2728 } else { 2729 Assert(buf != (char*)0, "lost buf"); 2730 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ 2731 } 2732 2733 /* If compression failed and this is the first and last block, 2734 * and if the .zip file can be seeked (to rewrite the local header), 2735 * the whole file is transformed into a stored file: 2736 */ 2737#ifdef STORED_FILE_OK 2738# ifdef FORCE_STORED_FILE 2739 if (eof && s->compressed_len == 0L) { /* force stored file */ 2740# else 2741 if (stored_len <= opt_lenb && eof && s->compressed_len==0L && seekable()) { 2742# endif 2743 /* Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there: */ 2744 if (buf == (charf*)0) error ("block vanished"); 2745 2746 copy_block(s, buf, (unsigned)stored_len, 0); /* without header */ 2747 s->compressed_len = stored_len << 3; 2748 s->method = STORED; 2749 } else 2750#endif /* STORED_FILE_OK */ 2751 2752#ifdef FORCE_STORED 2753 if (buf != (char*)0) { /* force stored block */ 2754#else 2755 if (stored_len+4 <= opt_lenb && buf != (char*)0) { 2756 /* 4: two words for the lengths */ 2757#endif 2758 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. 2759 * Otherwise we can't have processed more than WSIZE input bytes since 2760 * the last block flush, because compression would have been 2761 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to 2762 * transform a block into a stored block. 2763 */ 2764 _tr_stored_block(s, buf, stored_len, eof); 2765 2766#ifdef FORCE_STATIC 2767 } else if (static_lenb >= 0) { /* force static trees */ 2768#else 2769 } else if (static_lenb == opt_lenb) { 2770#endif 2771 send_bits(s, (STATIC_TREES<<1)+eof, 3); 2772 compress_block(s, (ct_data *)static_ltree, (ct_data *)static_dtree); 2773 s->compressed_len += 3 + s->static_len; 2774 } else { 2775 send_bits(s, (DYN_TREES<<1)+eof, 3); 2776 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, 2777 max_blindex+1); 2778 compress_block(s, (ct_data *)s->dyn_ltree, (ct_data *)s->dyn_dtree); 2779 s->compressed_len += 3 + s->opt_len; 2780 } 2781 Assert (s->compressed_len == s->bits_sent, "bad compressed size"); 2782 init_block(s); 2783 2784 if (eof) { 2785 bi_windup(s); 2786 s->compressed_len += 7; /* align on byte boundary */ 2787 } 2788 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, 2789 s->compressed_len-7*eof)); 2790 2791 return s->compressed_len >> 3; 2792} 2793 2794/* =========================================================================== 2795 * Save the match info and tally the frequency counts. Return true if 2796 * the current block must be flushed. 2797 */ 2798int _tr_tally (s, dist, lc) 2799 deflate_state *s; 2800 unsigned dist; /* distance of matched string */ 2801 unsigned lc; /* match length-MIN_MATCH or unmatched char (if dist==0) */ 2802{ 2803 s->d_buf[s->last_lit] = (ush)dist; 2804 s->l_buf[s->last_lit++] = (uch)lc; 2805 if (dist == 0) { 2806 /* lc is the unmatched char */ 2807 s->dyn_ltree[lc].Freq++; 2808 } else { 2809 s->matches++; 2810 /* Here, lc is the match length - MIN_MATCH */ 2811 dist--; /* dist = match distance - 1 */ 2812 Assert((ush)dist < (ush)MAX_DIST(s) && 2813 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && 2814 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); 2815 2816 s->dyn_ltree[length_code[lc]+LITERALS+1].Freq++; 2817 s->dyn_dtree[d_code(dist)].Freq++; 2818 } 2819 2820 /* Try to guess if it is profitable to stop the current block here */ 2821 if (s->level > 2 && (s->last_lit & 0xfff) == 0) { 2822 /* Compute an upper bound for the compressed length */ 2823 ulg out_length = (ulg)s->last_lit*8L; 2824 ulg in_length = (ulg)((long)s->strstart - s->block_start); 2825 int dcode; 2826 for (dcode = 0; dcode < D_CODES; dcode++) { 2827 out_length += (ulg)s->dyn_dtree[dcode].Freq * 2828 (5L+extra_dbits[dcode]); 2829 } 2830 out_length >>= 3; 2831 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", 2832 s->last_lit, in_length, out_length, 2833 100L - out_length*100L/in_length)); 2834 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; 2835 } 2836 return (s->last_lit == s->lit_bufsize-1); 2837 /* We avoid equality with lit_bufsize because of wraparound at 64K 2838 * on 16 bit machines and because stored blocks are restricted to 2839 * 64K-1 bytes. 2840 */ 2841} 2842 2843/* =========================================================================== 2844 * Send the block data compressed using the given Huffman trees 2845 */ 2846local void compress_block(s, ltree, dtree) 2847 deflate_state *s; 2848 ct_data *ltree; /* literal tree */ 2849 ct_data *dtree; /* distance tree */ 2850{ 2851 unsigned dist; /* distance of matched string */ 2852 int lc; /* match length or unmatched char (if dist == 0) */ 2853 unsigned lx = 0; /* running index in l_buf */ 2854 unsigned code; /* the code to send */ 2855 int extra; /* number of extra bits to send */ 2856 2857 if (s->last_lit != 0) do { 2858 dist = s->d_buf[lx]; 2859 lc = s->l_buf[lx++]; 2860 if (dist == 0) { 2861 send_code(s, lc, ltree); /* send a literal byte */ 2862 Tracecv(isgraph(lc), (stderr," '%c' ", lc)); 2863 } else { 2864 /* Here, lc is the match length - MIN_MATCH */ 2865 code = length_code[lc]; 2866 send_code(s, code+LITERALS+1, ltree); /* send the length code */ 2867 extra = extra_lbits[code]; 2868 if (extra != 0) { 2869 lc -= base_length[code]; 2870 send_bits(s, lc, extra); /* send the extra length bits */ 2871 } 2872 dist--; /* dist is now the match distance - 1 */ 2873 code = d_code(dist); 2874 Assert (code < D_CODES, "bad d_code"); 2875 2876 send_code(s, code, dtree); /* send the distance code */ 2877 extra = extra_dbits[code]; 2878 if (extra != 0) { 2879 dist -= base_dist[code]; 2880 send_bits(s, dist, extra); /* send the extra distance bits */ 2881 } 2882 } /* literal or match pair ? */ 2883 2884 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ 2885 Assert(s->pending < s->lit_bufsize + 2*lx, "pendingBuf overflow"); 2886 2887 } while (lx < s->last_lit); 2888 2889 send_code(s, END_BLOCK, ltree); 2890 s->last_eob_len = ltree[END_BLOCK].Len; 2891} 2892 2893/* =========================================================================== 2894 * Set the data type to ASCII or BINARY, using a crude approximation: 2895 * binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise. 2896 * IN assertion: the fields freq of dyn_ltree are set and the total of all 2897 * frequencies does not exceed 64K (to fit in an int on 16 bit machines). 2898 */ 2899local void set_data_type(s) 2900 deflate_state *s; 2901{ 2902 int n = 0; 2903 unsigned ascii_freq = 0; 2904 unsigned bin_freq = 0; 2905 while (n < 7) bin_freq += s->dyn_ltree[n++].Freq; 2906 while (n < 128) ascii_freq += s->dyn_ltree[n++].Freq; 2907 while (n < LITERALS) bin_freq += s->dyn_ltree[n++].Freq; 2908 s->data_type = (Byte)(bin_freq > (ascii_freq >> 2) ? Z_BINARY : Z_ASCII); 2909} 2910 2911/* =========================================================================== 2912 * Reverse the first len bits of a code, using straightforward code (a faster 2913 * method would use a table) 2914 * IN assertion: 1 <= len <= 15 2915 */ 2916local unsigned bi_reverse(code, len) 2917 unsigned code; /* the value to invert */ 2918 int len; /* its bit length */ 2919{ 2920 register unsigned res = 0; 2921 do { 2922 res |= code & 1; 2923 code >>= 1, res <<= 1; 2924 } while (--len > 0); 2925 return res >> 1; 2926} 2927 2928/* =========================================================================== 2929 * Flush the bit buffer, keeping at most 7 bits in it. 2930 */ 2931local void bi_flush(s) 2932 deflate_state *s; 2933{ 2934 if (s->bi_valid == 16) { 2935 put_short(s, s->bi_buf); 2936 s->bi_buf = 0; 2937 s->bi_valid = 0; 2938 } else if (s->bi_valid >= 8) { 2939 put_byte(s, (Byte)s->bi_buf); 2940 s->bi_buf >>= 8; 2941 s->bi_valid -= 8; 2942 } 2943} 2944 2945/* =========================================================================== 2946 * Flush the bit buffer and align the output on a byte boundary 2947 */ 2948local void bi_windup(s) 2949 deflate_state *s; 2950{ 2951 if (s->bi_valid > 8) { 2952 put_short(s, s->bi_buf); 2953 } else if (s->bi_valid > 0) { 2954 put_byte(s, (Byte)s->bi_buf); 2955 } 2956 s->bi_buf = 0; 2957 s->bi_valid = 0; 2958#ifdef DEBUG_ZLIB 2959 s->bits_sent = (s->bits_sent+7) & ~7; 2960#endif 2961} 2962 2963/* =========================================================================== 2964 * Copy a stored block, storing first the length and its 2965 * one's complement if requested. 2966 */ 2967local void copy_block(s, buf, len, header) 2968 deflate_state *s; 2969 charf *buf; /* the input data */ 2970 unsigned len; /* its length */ 2971 int header; /* true if block header must be written */ 2972{ 2973 bi_windup(s); /* align on byte boundary */ 2974 s->last_eob_len = 8; /* enough lookahead for inflate */ 2975 2976 if (header) { 2977 put_short(s, (ush)len); 2978 put_short(s, (ush)~len); 2979#ifdef DEBUG_ZLIB 2980 s->bits_sent += 2*16; 2981#endif 2982 } 2983#ifdef DEBUG_ZLIB 2984 s->bits_sent += (ulg)len<<3; 2985#endif 2986 /* bundle up the put_byte(s, *buf++) calls */ 2987 zmemcpy(&s->pending_buf[s->pending], buf, len); 2988 s->pending += len; 2989} 2990/* --- trees.c */ 2991 2992/* +++ inflate.c */ 2993/* inflate.c -- zlib interface to inflate modules 2994 * Copyright (C) 1995-1996 Mark Adler 2995 * For conditions of distribution and use, see copyright notice in zlib.h 2996 */ 2997 2998/* #include "zutil.h" */ 2999 3000/* +++ infblock.h */ 3001/* infblock.h -- header to use infblock.c 3002 * Copyright (C) 1995-1996 Mark Adler 3003 * For conditions of distribution and use, see copyright notice in zlib.h 3004 */ 3005 3006/* WARNING: this file should *not* be used by applications. It is 3007 part of the implementation of the compression library and is 3008 subject to change. Applications should only use zlib.h. 3009 */ 3010 3011struct inflate_blocks_state; 3012typedef struct inflate_blocks_state FAR inflate_blocks_statef; 3013 3014extern inflate_blocks_statef * inflate_blocks_new OF(( 3015 z_streamp z, 3016 check_func c, /* check function */ 3017 uInt w)); /* window size */ 3018 3019extern int inflate_blocks OF(( 3020 inflate_blocks_statef *, 3021 z_streamp , 3022 int)); /* initial return code */ 3023 3024extern void inflate_blocks_reset OF(( 3025 inflate_blocks_statef *, 3026 z_streamp , 3027 uLongf *)); /* check value on output */ 3028 3029extern int inflate_blocks_free OF(( 3030 inflate_blocks_statef *, 3031 z_streamp , 3032 uLongf *)); /* check value on output */ 3033 3034extern void inflate_set_dictionary OF(( 3035 inflate_blocks_statef *s, 3036 const Bytef *d, /* dictionary */ 3037 uInt n)); /* dictionary length */ 3038 3039extern int inflate_addhistory OF(( 3040 inflate_blocks_statef *, 3041 z_streamp)); 3042 3043extern int inflate_packet_flush OF(( 3044 inflate_blocks_statef *)); 3045/* --- infblock.h */ 3046 3047#ifndef NO_DUMMY_DECL 3048struct inflate_blocks_state {int dummy;}; /* for buggy compilers */ 3049#endif 3050 3051/* inflate private state */ 3052struct internal_state { 3053 3054 /* mode */ 3055 enum { 3056 METHOD, /* waiting for method byte */ 3057 FLAG, /* waiting for flag byte */ 3058 DICT4, /* four dictionary check bytes to go */ 3059 DICT3, /* three dictionary check bytes to go */ 3060 DICT2, /* two dictionary check bytes to go */ 3061 DICT1, /* one dictionary check byte to go */ 3062 DICT0, /* waiting for inflateSetDictionary */ 3063 BLOCKS, /* decompressing blocks */ 3064 CHECK4, /* four check bytes to go */ 3065 CHECK3, /* three check bytes to go */ 3066 CHECK2, /* two check bytes to go */ 3067 CHECK1, /* one check byte to go */ 3068 DONE, /* finished check, done */ 3069 BAD} /* got an error--stay here */ 3070 mode; /* current inflate mode */ 3071 3072 /* mode dependent information */ 3073 union { 3074 uInt method; /* if FLAGS, method byte */ 3075 struct { 3076 uLong was; /* computed check value */ 3077 uLong need; /* stream check value */ 3078 } check; /* if CHECK, check values to compare */ 3079 uInt marker; /* if BAD, inflateSync's marker bytes count */ 3080 } sub; /* submode */ 3081 3082 /* mode independent information */ 3083 int nowrap; /* flag for no wrapper */ 3084 uInt wbits; /* log2(window size) (8..15, defaults to 15) */ 3085 inflate_blocks_statef 3086 *blocks; /* current inflate_blocks state */ 3087 3088}; 3089 3090 3091int inflateReset(z) 3092z_streamp z; 3093{ 3094 uLong c; 3095 3096 if (z == Z_NULL || z->state == Z_NULL) 3097 return Z_STREAM_ERROR; 3098 z->total_in = z->total_out = 0; 3099 z->msg = Z_NULL; 3100 z->state->mode = z->state->nowrap ? BLOCKS : METHOD; 3101 inflate_blocks_reset(z->state->blocks, z, &c); 3102 Trace((stderr, "inflate: reset\n")); 3103 return Z_OK; 3104} 3105 3106 3107int inflateEnd(z) 3108z_streamp z; 3109{ 3110 uLong c; 3111 3112 if (z == Z_NULL || z->state == Z_NULL || z->zfree == Z_NULL) 3113 return Z_STREAM_ERROR; 3114 if (z->state->blocks != Z_NULL) 3115 inflate_blocks_free(z->state->blocks, z, &c); 3116 ZFREE(z, z->state); 3117 z->state = Z_NULL; 3118 Trace((stderr, "inflate: end\n")); 3119 return Z_OK; 3120} 3121 3122 3123int inflateInit2_(z, w, version, stream_size) 3124z_streamp z; 3125int w; 3126const char *version; 3127int stream_size; 3128{ 3129 if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || 3130 stream_size != sizeof(z_stream)) 3131 return Z_VERSION_ERROR; 3132 3133 /* initialize state */ 3134 if (z == Z_NULL) 3135 return Z_STREAM_ERROR; 3136 z->msg = Z_NULL; 3137#ifndef NO_ZCFUNCS 3138 if (z->zalloc == Z_NULL) 3139 { 3140 z->zalloc = zcalloc; 3141 z->opaque = (voidpf)0; 3142 } 3143 if (z->zfree == Z_NULL) z->zfree = zcfree; 3144#endif 3145 if ((z->state = (struct internal_state FAR *) 3146 ZALLOC(z,1,sizeof(struct internal_state))) == Z_NULL) 3147 return Z_MEM_ERROR; 3148 z->state->blocks = Z_NULL; 3149 3150 /* handle undocumented nowrap option (no zlib header or check) */ 3151 z->state->nowrap = 0; 3152 if (w < 0) 3153 { 3154 w = - w; 3155 z->state->nowrap = 1; 3156 } 3157 3158 /* set window size */ 3159 if (w < 8 || w > 15) 3160 { 3161 inflateEnd(z); 3162 return Z_STREAM_ERROR; 3163 } 3164 z->state->wbits = (uInt)w; 3165 3166 /* create inflate_blocks state */ 3167 if ((z->state->blocks = 3168 inflate_blocks_new(z, z->state->nowrap ? Z_NULL : adler32, (uInt)1 << w)) 3169 == Z_NULL) 3170 { 3171 inflateEnd(z); 3172 return Z_MEM_ERROR; 3173 } 3174 Trace((stderr, "inflate: allocated\n")); 3175 3176 /* reset state */ 3177 inflateReset(z); 3178 return Z_OK; 3179} 3180 3181 3182int inflateInit_(z, version, stream_size) 3183z_streamp z; 3184const char *version; 3185int stream_size; 3186{ 3187 return inflateInit2_(z, DEF_WBITS, version, stream_size); 3188} 3189 3190 3191#define NEEDBYTE {if(z->avail_in==0)goto empty;r=Z_OK;} 3192#define NEXTBYTE (z->avail_in--,z->total_in++,*z->next_in++) 3193 3194int inflate(z, f) 3195z_streamp z; 3196int f; 3197{ 3198 int r; 3199 uInt b; 3200 3201 if (z == Z_NULL || z->state == Z_NULL || z->next_in == Z_NULL || f < 0) 3202 return Z_STREAM_ERROR; 3203 r = Z_BUF_ERROR; 3204 while (1) switch (z->state->mode) 3205 { 3206 case METHOD: 3207 NEEDBYTE 3208 if (((z->state->sub.method = NEXTBYTE) & 0xf) != Z_DEFLATED) 3209 { 3210 z->state->mode = BAD; 3211 z->msg = (char*)"unknown compression method"; 3212 z->state->sub.marker = 5; /* can't try inflateSync */ 3213 break; 3214 } 3215 if ((z->state->sub.method >> 4) + 8 > z->state->wbits) 3216 { 3217 z->state->mode = BAD; 3218 z->msg = (char*)"invalid window size"; 3219 z->state->sub.marker = 5; /* can't try inflateSync */ 3220 break; 3221 } 3222 z->state->mode = FLAG; 3223 case FLAG: 3224 NEEDBYTE 3225 b = NEXTBYTE; 3226 if (((z->state->sub.method << 8) + b) % 31) 3227 { 3228 z->state->mode = BAD; 3229 z->msg = (char*)"incorrect header check"; 3230 z->state->sub.marker = 5; /* can't try inflateSync */ 3231 break; 3232 } 3233 Trace((stderr, "inflate: zlib header ok\n")); 3234 if (!(b & PRESET_DICT)) 3235 { 3236 z->state->mode = BLOCKS; 3237 break; 3238 } 3239 z->state->mode = DICT4; 3240 case DICT4: 3241 NEEDBYTE 3242 z->state->sub.check.need = (uLong)NEXTBYTE << 24; 3243 z->state->mode = DICT3; 3244 case DICT3: 3245 NEEDBYTE 3246 z->state->sub.check.need += (uLong)NEXTBYTE << 16; 3247 z->state->mode = DICT2; 3248 case DICT2: 3249 NEEDBYTE 3250 z->state->sub.check.need += (uLong)NEXTBYTE << 8; 3251 z->state->mode = DICT1; 3252 case DICT1: 3253 NEEDBYTE 3254 z->state->sub.check.need += (uLong)NEXTBYTE; 3255 z->adler = z->state->sub.check.need; 3256 z->state->mode = DICT0; 3257 return Z_NEED_DICT; 3258 case DICT0: 3259 z->state->mode = BAD; 3260 z->msg = (char*)"need dictionary"; 3261 z->state->sub.marker = 0; /* can try inflateSync */ 3262 return Z_STREAM_ERROR; 3263 case BLOCKS: 3264 r = inflate_blocks(z->state->blocks, z, r); 3265 if (f == Z_PACKET_FLUSH && z->avail_in == 0 && z->avail_out != 0) 3266 r = inflate_packet_flush(z->state->blocks); 3267 if (r == Z_DATA_ERROR) 3268 { 3269 z->state->mode = BAD; 3270 z->state->sub.marker = 0; /* can try inflateSync */ 3271 break; 3272 } 3273 if (r != Z_STREAM_END) 3274 return r; 3275 r = Z_OK; 3276 inflate_blocks_reset(z->state->blocks, z, &z->state->sub.check.was); 3277 if (z->state->nowrap) 3278 { 3279 z->state->mode = DONE; 3280 break; 3281 } 3282 z->state->mode = CHECK4; 3283 case CHECK4: 3284 NEEDBYTE 3285 z->state->sub.check.need = (uLong)NEXTBYTE << 24; 3286 z->state->mode = CHECK3; 3287 case CHECK3: 3288 NEEDBYTE 3289 z->state->sub.check.need += (uLong)NEXTBYTE << 16; 3290 z->state->mode = CHECK2; 3291 case CHECK2: 3292 NEEDBYTE 3293 z->state->sub.check.need += (uLong)NEXTBYTE << 8; 3294 z->state->mode = CHECK1; 3295 case CHECK1: 3296 NEEDBYTE 3297 z->state->sub.check.need += (uLong)NEXTBYTE; 3298 3299 if (z->state->sub.check.was != z->state->sub.check.need) 3300 { 3301 z->state->mode = BAD; 3302 z->msg = (char*)"incorrect data check"; 3303 z->state->sub.marker = 5; /* can't try inflateSync */ 3304 break; 3305 } 3306 Trace((stderr, "inflate: zlib check ok\n")); 3307 z->state->mode = DONE; 3308 case DONE: 3309 return Z_STREAM_END; 3310 case BAD: 3311 return Z_DATA_ERROR; 3312 default: 3313 return Z_STREAM_ERROR; 3314 } 3315 3316 empty: 3317 if (f != Z_PACKET_FLUSH) 3318 return r; 3319 z->state->mode = BAD; 3320 z->msg = (char *)"need more for packet flush"; 3321 z->state->sub.marker = 0; /* can try inflateSync */ 3322 return Z_DATA_ERROR; 3323} 3324 3325 3326int inflateSetDictionary(z, dictionary, dictLength) 3327z_streamp z; 3328const Bytef *dictionary; 3329uInt dictLength; 3330{ 3331 uInt length = dictLength; 3332 3333 if (z == Z_NULL || z->state == Z_NULL || z->state->mode != DICT0) 3334 return Z_STREAM_ERROR; 3335 3336 if (adler32(1L, dictionary, dictLength) != z->adler) return Z_DATA_ERROR; 3337 z->adler = 1L; 3338 3339 if (length >= ((uInt)1<<z->state->wbits)) 3340 { 3341 length = (1<<z->state->wbits)-1; 3342 dictionary += dictLength - length; 3343 } 3344 inflate_set_dictionary(z->state->blocks, dictionary, length); 3345 z->state->mode = BLOCKS; 3346 return Z_OK; 3347} 3348 3349/* 3350 * This subroutine adds the data at next_in/avail_in to the output history 3351 * without performing any output. The output buffer must be "caught up"; 3352 * i.e. no pending output (hence s->read equals s->write), and the state must 3353 * be BLOCKS (i.e. we should be willing to see the start of a series of 3354 * BLOCKS). On exit, the output will also be caught up, and the checksum 3355 * will have been updated if need be. 3356 */ 3357 3358int inflateIncomp(z) 3359z_stream *z; 3360{ 3361 if (z->state->mode != BLOCKS) 3362 return Z_DATA_ERROR; 3363 return inflate_addhistory(z->state->blocks, z); 3364} 3365 3366 3367int inflateSync(z) 3368z_streamp z; 3369{ 3370 uInt n; /* number of bytes to look at */ 3371 Bytef *p; /* pointer to bytes */ 3372 uInt m; /* number of marker bytes found in a row */ 3373 uLong r, w; /* temporaries to save total_in and total_out */ 3374 3375 /* set up */ 3376 if (z == Z_NULL || z->state == Z_NULL) 3377 return Z_STREAM_ERROR; 3378 if (z->state->mode != BAD) 3379 { 3380 z->state->mode = BAD; 3381 z->state->sub.marker = 0; 3382 } 3383 if ((n = z->avail_in) == 0) 3384 return Z_BUF_ERROR; 3385 p = z->next_in; 3386 m = z->state->sub.marker; 3387 3388 /* search */ 3389 while (n && m < 4) 3390 { 3391 if (*p == (Byte)(m < 2 ? 0 : 0xff)) 3392 m++; 3393 else if (*p) 3394 m = 0; 3395 else 3396 m = 4 - m; 3397 p++, n--; 3398 } 3399 3400 /* restore */ 3401 z->total_in += p - z->next_in; 3402 z->next_in = p; 3403 z->avail_in = n; 3404 z->state->sub.marker = m; 3405 3406 /* return no joy or set up to restart on a new block */ 3407 if (m != 4) 3408 return Z_DATA_ERROR; 3409 r = z->total_in; w = z->total_out; 3410 inflateReset(z); 3411 z->total_in = r; z->total_out = w; 3412 z->state->mode = BLOCKS; 3413 return Z_OK; 3414} 3415 3416#undef NEEDBYTE 3417#undef NEXTBYTE 3418/* --- inflate.c */ 3419 3420/* +++ infblock.c */ 3421/* infblock.c -- interpret and process block types to last block 3422 * Copyright (C) 1995-1996 Mark Adler 3423 * For conditions of distribution and use, see copyright notice in zlib.h 3424 */ 3425 3426/* #include "zutil.h" */ 3427/* #include "infblock.h" */ 3428 3429/* +++ inftrees.h */ 3430/* inftrees.h -- header to use inftrees.c 3431 * Copyright (C) 1995-1996 Mark Adler 3432 * For conditions of distribution and use, see copyright notice in zlib.h 3433 */ 3434 3435/* WARNING: this file should *not* be used by applications. It is 3436 part of the implementation of the compression library and is 3437 subject to change. Applications should only use zlib.h. 3438 */ 3439 3440/* Huffman code lookup table entry--this entry is four bytes for machines 3441 that have 16-bit pointers (e.g. PC's in the small or medium model). */ 3442 3443typedef struct inflate_huft_s FAR inflate_huft; 3444 3445struct inflate_huft_s { 3446 union { 3447 struct { 3448 Byte Exop; /* number of extra bits or operation */ 3449 Byte Bits; /* number of bits in this code or subcode */ 3450 } what; 3451 Bytef *pad; /* pad structure to a power of 2 (4 bytes for */ 3452 } word; /* 16-bit, 8 bytes for 32-bit machines) */ 3453 union { 3454 uInt Base; /* literal, length base, or distance base */ 3455 inflate_huft *Next; /* pointer to next level of table */ 3456 } more; 3457}; 3458 3459#ifdef DEBUG_ZLIB 3460 extern uInt inflate_hufts; 3461#endif 3462 3463extern int inflate_trees_bits OF(( 3464 uIntf *, /* 19 code lengths */ 3465 uIntf *, /* bits tree desired/actual depth */ 3466 inflate_huft * FAR *, /* bits tree result */ 3467 z_streamp )); /* for zalloc, zfree functions */ 3468 3469extern int inflate_trees_dynamic OF(( 3470 uInt, /* number of literal/length codes */ 3471 uInt, /* number of distance codes */ 3472 uIntf *, /* that many (total) code lengths */ 3473 uIntf *, /* literal desired/actual bit depth */ 3474 uIntf *, /* distance desired/actual bit depth */ 3475 inflate_huft * FAR *, /* literal/length tree result */ 3476 inflate_huft * FAR *, /* distance tree result */ 3477 z_streamp )); /* for zalloc, zfree functions */ 3478 3479extern int inflate_trees_fixed OF(( 3480 uIntf *, /* literal desired/actual bit depth */ 3481 uIntf *, /* distance desired/actual bit depth */ 3482 inflate_huft * FAR *, /* literal/length tree result */ 3483 inflate_huft * FAR *)); /* distance tree result */ 3484 3485extern int inflate_trees_free OF(( 3486 inflate_huft *, /* tables to free */ 3487 z_streamp )); /* for zfree function */ 3488 3489/* --- inftrees.h */ 3490 3491/* +++ infcodes.h */ 3492/* infcodes.h -- header to use infcodes.c 3493 * Copyright (C) 1995-1996 Mark Adler 3494 * For conditions of distribution and use, see copyright notice in zlib.h 3495 */ 3496 3497/* WARNING: this file should *not* be used by applications. It is 3498 part of the implementation of the compression library and is 3499 subject to change. Applications should only use zlib.h. 3500 */ 3501 3502struct inflate_codes_state; 3503typedef struct inflate_codes_state FAR inflate_codes_statef; 3504 3505extern inflate_codes_statef *inflate_codes_new OF(( 3506 uInt, uInt, 3507 inflate_huft *, inflate_huft *, 3508 z_streamp )); 3509 3510extern int inflate_codes OF(( 3511 inflate_blocks_statef *, 3512 z_streamp , 3513 int)); 3514 3515extern void inflate_codes_free OF(( 3516 inflate_codes_statef *, 3517 z_streamp )); 3518 3519/* --- infcodes.h */ 3520 3521/* +++ infutil.h */ 3522/* infutil.h -- types and macros common to blocks and codes 3523 * Copyright (C) 1995-1996 Mark Adler 3524 * For conditions of distribution and use, see copyright notice in zlib.h 3525 */ 3526 3527/* WARNING: this file should *not* be used by applications. It is 3528 part of the implementation of the compression library and is 3529 subject to change. Applications should only use zlib.h. 3530 */ 3531 3532#ifndef _INFUTIL_H 3533#define _INFUTIL_H 3534 3535typedef enum { 3536 TYPE, /* get type bits (3, including end bit) */ 3537 LENS, /* get lengths for stored */ 3538 STORED, /* processing stored block */ 3539 TABLE, /* get table lengths */ 3540 BTREE, /* get bit lengths tree for a dynamic block */ 3541 DTREE, /* get length, distance trees for a dynamic block */ 3542 CODES, /* processing fixed or dynamic block */ 3543 DRY, /* output remaining window bytes */ 3544 DONEB, /* finished last block, done */ 3545 BADB} /* got a data error--stuck here */ 3546inflate_block_mode; 3547 3548/* inflate blocks semi-private state */ 3549struct inflate_blocks_state { 3550 3551 /* mode */ 3552 inflate_block_mode mode; /* current inflate_block mode */ 3553 3554 /* mode dependent information */ 3555 union { 3556 uInt left; /* if STORED, bytes left to copy */ 3557 struct { 3558 uInt table; /* table lengths (14 bits) */ 3559 uInt index; /* index into blens (or border) */ 3560 uIntf *blens; /* bit lengths of codes */ 3561 uInt bb; /* bit length tree depth */ 3562 inflate_huft *tb; /* bit length decoding tree */ 3563 } trees; /* if DTREE, decoding info for trees */ 3564 struct { 3565 inflate_huft *tl; 3566 inflate_huft *td; /* trees to free */ 3567 inflate_codes_statef 3568 *codes; 3569 } decode; /* if CODES, current state */ 3570 } sub; /* submode */ 3571 uInt last; /* true if this block is the last block */ 3572 3573 /* mode independent information */ 3574 uInt bitk; /* bits in bit buffer */ 3575 uLong bitb; /* bit buffer */ 3576 Bytef *window; /* sliding window */ 3577 Bytef *end; /* one byte after sliding window */ 3578 Bytef *read; /* window read pointer */ 3579 Bytef *write; /* window write pointer */ 3580 check_func checkfn; /* check function */ 3581 uLong check; /* check on output */ 3582 3583}; 3584 3585 3586/* defines for inflate input/output */ 3587/* update pointers and return */ 3588#define UPDBITS {s->bitb=b;s->bitk=k;} 3589#define UPDIN {z->avail_in=n;z->total_in+=p-z->next_in;z->next_in=p;} 3590#define UPDOUT {s->write=q;} 3591#define UPDATE {UPDBITS UPDIN UPDOUT} 3592#define LEAVE {UPDATE return inflate_flush(s,z,r);} 3593/* get bytes and bits */ 3594#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;} 3595#define NEEDBYTE {if(n)r=Z_OK;else LEAVE} 3596#define NEXTBYTE (n--,*p++) 3597#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}} 3598#define DUMPBITS(j) {b>>=(j);k-=(j);} 3599/* output bytes */ 3600#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q) 3601#define LOADOUT {q=s->write;m=(uInt)WAVAIL;} 3602#define WWRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}} 3603#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT} 3604#define NEEDOUT {if(m==0){WWRAP if(m==0){FLUSH WWRAP if(m==0) LEAVE}}r=Z_OK;} 3605#define OUTBYTE(a) {*q++=(Byte)(a);m--;} 3606/* load local pointers */ 3607#define LOAD {LOADIN LOADOUT} 3608 3609/* masks for lower bits (size given to avoid silly warnings with Visual C++) */ 3610extern uInt inflate_mask[17]; 3611 3612/* copy as much as possible from the sliding window to the output area */ 3613extern int inflate_flush OF(( 3614 inflate_blocks_statef *, 3615 z_streamp , 3616 int)); 3617 3618#ifndef NO_DUMMY_DECL 3619struct internal_state {int dummy;}; /* for buggy compilers */ 3620#endif 3621 3622#endif 3623/* --- infutil.h */ 3624 3625#ifndef NO_DUMMY_DECL 3626struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 3627#endif 3628 3629/* Table for deflate from PKZIP's appnote.txt. */ 3630local const uInt border[] = { /* Order of the bit length code lengths */ 3631 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; 3632 3633/* 3634 Notes beyond the 1.93a appnote.txt: 3635 3636 1. Distance pointers never point before the beginning of the output 3637 stream. 3638 2. Distance pointers can point back across blocks, up to 32k away. 3639 3. There is an implied maximum of 7 bits for the bit length table and 3640 15 bits for the actual data. 3641 4. If only one code exists, then it is encoded using one bit. (Zero 3642 would be more efficient, but perhaps a little confusing.) If two 3643 codes exist, they are coded using one bit each (0 and 1). 3644 5. There is no way of sending zero distance codes--a dummy must be 3645 sent if there are none. (History: a pre 2.0 version of PKZIP would 3646 store blocks with no distance codes, but this was discovered to be 3647 too harsh a criterion.) Valid only for 1.93a. 2.04c does allow 3648 zero distance codes, which is sent as one code of zero bits in 3649 length. 3650 6. There are up to 286 literal/length codes. Code 256 represents the 3651 end-of-block. Note however that the static length tree defines 3652 288 codes just to fill out the Huffman codes. Codes 286 and 287 3653 cannot be used though, since there is no length base or extra bits 3654 defined for them. Similarily, there are up to 30 distance codes. 3655 However, static trees define 32 codes (all 5 bits) to fill out the 3656 Huffman codes, but the last two had better not show up in the data. 3657 7. Unzip can check dynamic Huffman blocks for complete code sets. 3658 The exception is that a single code would not be complete (see #4). 3659 8. The five bits following the block type is really the number of 3660 literal codes sent minus 257. 3661 9. Length codes 8,16,16 are interpreted as 13 length codes of 8 bits 3662 (1+6+6). Therefore, to output three times the length, you output 3663 three codes (1+1+1), whereas to output four times the same length, 3664 you only need two codes (1+3). Hmm. 3665 10. In the tree reconstruction algorithm, Code = Code + Increment 3666 only if BitLength(i) is not zero. (Pretty obvious.) 3667 11. Correction: 4 Bits: # of Bit Length codes - 4 (4 - 19) 3668 12. Note: length code 284 can represent 227-258, but length code 285 3669 really is 258. The last length deserves its own, short code 3670 since it gets used a lot in very redundant files. The length 3671 258 is special since 258 - 3 (the min match length) is 255. 3672 13. The literal/length and distance code bit lengths are read as a 3673 single stream of lengths. It is possible (and advantageous) for 3674 a repeat code (16, 17, or 18) to go across the boundary between 3675 the two sets of lengths. 3676 */ 3677 3678 3679void inflate_blocks_reset(s, z, c) 3680inflate_blocks_statef *s; 3681z_streamp z; 3682uLongf *c; 3683{ 3684 if (s->checkfn != Z_NULL) 3685 *c = s->check; 3686 if (s->mode == BTREE || s->mode == DTREE) 3687 ZFREE(z, s->sub.trees.blens); 3688 if (s->mode == CODES) 3689 { 3690 inflate_codes_free(s->sub.decode.codes, z); 3691 inflate_trees_free(s->sub.decode.td, z); 3692 inflate_trees_free(s->sub.decode.tl, z); 3693 } 3694 s->mode = TYPE; 3695 s->bitk = 0; 3696 s->bitb = 0; 3697 s->read = s->write = s->window; 3698 if (s->checkfn != Z_NULL) 3699 z->adler = s->check = (*s->checkfn)(0L, Z_NULL, 0); 3700 Trace((stderr, "inflate: blocks reset\n")); 3701} 3702 3703 3704inflate_blocks_statef *inflate_blocks_new(z, c, w) 3705z_streamp z; 3706check_func c; 3707uInt w; 3708{ 3709 inflate_blocks_statef *s; 3710 3711 if ((s = (inflate_blocks_statef *)ZALLOC 3712 (z,1,sizeof(struct inflate_blocks_state))) == Z_NULL) 3713 return s; 3714 if ((s->window = (Bytef *)ZALLOC(z, 1, w)) == Z_NULL) 3715 { 3716 ZFREE(z, s); 3717 return Z_NULL; 3718 } 3719 s->end = s->window + w; 3720 s->checkfn = c; 3721 s->mode = TYPE; 3722 Trace((stderr, "inflate: blocks allocated\n")); 3723 inflate_blocks_reset(s, z, &s->check); 3724 return s; 3725} 3726 3727 3728#ifdef DEBUG_ZLIB 3729 extern uInt inflate_hufts; 3730#endif 3731int inflate_blocks(s, z, r) 3732inflate_blocks_statef *s; 3733z_streamp z; 3734int r; 3735{ 3736 uInt t; /* temporary storage */ 3737 uLong b; /* bit buffer */ 3738 uInt k; /* bits in bit buffer */ 3739 Bytef *p; /* input data pointer */ 3740 uInt n; /* bytes available there */ 3741 Bytef *q; /* output window write pointer */ 3742 uInt m; /* bytes to end of window or read pointer */ 3743 3744 /* copy input/output information to locals (UPDATE macro restores) */ 3745 LOAD 3746 3747 /* process input based on current state */ 3748 while (1) switch (s->mode) 3749 { 3750 case TYPE: 3751 NEEDBITS(3) 3752 t = (uInt)b & 7; 3753 s->last = t & 1; 3754 switch (t >> 1) 3755 { 3756 case 0: /* stored */ 3757 Trace((stderr, "inflate: stored block%s\n", 3758 s->last ? " (last)" : "")); 3759 DUMPBITS(3) 3760 t = k & 7; /* go to byte boundary */ 3761 DUMPBITS(t) 3762 s->mode = LENS; /* get length of stored block */ 3763 break; 3764 case 1: /* fixed */ 3765 Trace((stderr, "inflate: fixed codes block%s\n", 3766 s->last ? " (last)" : "")); 3767 { 3768 uInt bl, bd; 3769 inflate_huft *tl, *td; 3770 3771 inflate_trees_fixed(&bl, &bd, &tl, &td); 3772 s->sub.decode.codes = inflate_codes_new(bl, bd, tl, td, z); 3773 if (s->sub.decode.codes == Z_NULL) 3774 { 3775 r = Z_MEM_ERROR; 3776 LEAVE 3777 } 3778 s->sub.decode.tl = Z_NULL; /* don't try to free these */ 3779 s->sub.decode.td = Z_NULL; 3780 } 3781 DUMPBITS(3) 3782 s->mode = CODES; 3783 break; 3784 case 2: /* dynamic */ 3785 Trace((stderr, "inflate: dynamic codes block%s\n", 3786 s->last ? " (last)" : "")); 3787 DUMPBITS(3) 3788 s->mode = TABLE; 3789 break; 3790 case 3: /* illegal */ 3791 DUMPBITS(3) 3792 s->mode = BADB; 3793 z->msg = (char*)"invalid block type"; 3794 r = Z_DATA_ERROR; 3795 LEAVE 3796 } 3797 break; 3798 case LENS: 3799 NEEDBITS(32) 3800 if ((((~b) >> 16) & 0xffff) != (b & 0xffff)) 3801 { 3802 s->mode = BADB; 3803 z->msg = (char*)"invalid stored block lengths"; 3804 r = Z_DATA_ERROR; 3805 LEAVE 3806 } 3807 s->sub.left = (uInt)b & 0xffff; 3808 b = k = 0; /* dump bits */ 3809 Tracev((stderr, "inflate: stored length %u\n", s->sub.left)); 3810 s->mode = s->sub.left ? STORED : (s->last ? DRY : TYPE); 3811 break; 3812 case STORED: 3813 if (n == 0) 3814 LEAVE 3815 NEEDOUT 3816 t = s->sub.left; 3817 if (t > n) t = n; 3818 if (t > m) t = m; 3819 zmemcpy(q, p, t); 3820 p += t; n -= t; 3821 q += t; m -= t; 3822 if ((s->sub.left -= t) != 0) 3823 break; 3824 Tracev((stderr, "inflate: stored end, %lu total out\n", 3825 z->total_out + (q >= s->read ? q - s->read : 3826 (s->end - s->read) + (q - s->window)))); 3827 s->mode = s->last ? DRY : TYPE; 3828 break; 3829 case TABLE: 3830 NEEDBITS(14) 3831 s->sub.trees.table = t = (uInt)b & 0x3fff; 3832#ifndef PKZIP_BUG_WORKAROUND 3833 if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29) 3834 { 3835 s->mode = BADB; 3836 z->msg = (char*)"too many length or distance symbols"; 3837 r = Z_DATA_ERROR; 3838 LEAVE 3839 } 3840#endif 3841 t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f); 3842 if (t < 19) 3843 t = 19; 3844 if ((s->sub.trees.blens = (uIntf*)ZALLOC(z, t, sizeof(uInt))) == Z_NULL) 3845 { 3846 r = Z_MEM_ERROR; 3847 LEAVE 3848 } 3849 DUMPBITS(14) 3850 s->sub.trees.index = 0; 3851 Tracev((stderr, "inflate: table sizes ok\n")); 3852 s->mode = BTREE; 3853 case BTREE: 3854 while (s->sub.trees.index < 4 + (s->sub.trees.table >> 10)) 3855 { 3856 NEEDBITS(3) 3857 s->sub.trees.blens[border[s->sub.trees.index++]] = (uInt)b & 7; 3858 DUMPBITS(3) 3859 } 3860 while (s->sub.trees.index < 19) 3861 s->sub.trees.blens[border[s->sub.trees.index++]] = 0; 3862 s->sub.trees.bb = 7; 3863 t = inflate_trees_bits(s->sub.trees.blens, &s->sub.trees.bb, 3864 &s->sub.trees.tb, z); 3865 if (t != Z_OK) 3866 { 3867 ZFREE(z, s->sub.trees.blens); 3868 r = t; 3869 if (r == Z_DATA_ERROR) 3870 s->mode = BADB; 3871 LEAVE 3872 } 3873 s->sub.trees.index = 0; 3874 Tracev((stderr, "inflate: bits tree ok\n")); 3875 s->mode = DTREE; 3876 case DTREE: 3877 while (t = s->sub.trees.table, 3878 s->sub.trees.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)) 3879 { 3880 inflate_huft *h; 3881 uInt i, j, c; 3882 3883 t = s->sub.trees.bb; 3884 NEEDBITS(t) 3885 h = s->sub.trees.tb + ((uInt)b & inflate_mask[t]); 3886 t = h->word.what.Bits; 3887 c = h->more.Base; 3888 if (c < 16) 3889 { 3890 DUMPBITS(t) 3891 s->sub.trees.blens[s->sub.trees.index++] = c; 3892 } 3893 else /* c == 16..18 */ 3894 { 3895 i = c == 18 ? 7 : c - 14; 3896 j = c == 18 ? 11 : 3; 3897 NEEDBITS(t + i) 3898 DUMPBITS(t) 3899 j += (uInt)b & inflate_mask[i]; 3900 DUMPBITS(i) 3901 i = s->sub.trees.index; 3902 t = s->sub.trees.table; 3903 if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || 3904 (c == 16 && i < 1)) 3905 { 3906 inflate_trees_free(s->sub.trees.tb, z); 3907 ZFREE(z, s->sub.trees.blens); 3908 s->mode = BADB; 3909 z->msg = (char*)"invalid bit length repeat"; 3910 r = Z_DATA_ERROR; 3911 LEAVE 3912 } 3913 c = c == 16 ? s->sub.trees.blens[i - 1] : 0; 3914 do { 3915 s->sub.trees.blens[i++] = c; 3916 } while (--j); 3917 s->sub.trees.index = i; 3918 } 3919 } 3920 inflate_trees_free(s->sub.trees.tb, z); 3921 s->sub.trees.tb = Z_NULL; 3922 { 3923 uInt bl, bd; 3924 inflate_huft *tl, *td; 3925 inflate_codes_statef *c; 3926 3927 bl = 9; /* must be <= 9 for lookahead assumptions */ 3928 bd = 6; /* must be <= 9 for lookahead assumptions */ 3929 t = s->sub.trees.table; 3930#ifdef DEBUG_ZLIB 3931 inflate_hufts = 0; 3932#endif 3933 t = inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), 3934 s->sub.trees.blens, &bl, &bd, &tl, &td, z); 3935 ZFREE(z, s->sub.trees.blens); 3936 if (t != Z_OK) 3937 { 3938 if (t == (uInt)Z_DATA_ERROR) 3939 s->mode = BADB; 3940 r = t; 3941 LEAVE 3942 } 3943 Tracev((stderr, "inflate: trees ok, %d * %d bytes used\n", 3944 inflate_hufts, sizeof(inflate_huft))); 3945 if ((c = inflate_codes_new(bl, bd, tl, td, z)) == Z_NULL) 3946 { 3947 inflate_trees_free(td, z); 3948 inflate_trees_free(tl, z); 3949 r = Z_MEM_ERROR; 3950 LEAVE 3951 } 3952 s->sub.decode.codes = c; 3953 s->sub.decode.tl = tl; 3954 s->sub.decode.td = td; 3955 } 3956 s->mode = CODES; 3957 case CODES: 3958 UPDATE 3959 if ((r = inflate_codes(s, z, r)) != Z_STREAM_END) 3960 return inflate_flush(s, z, r); 3961 r = Z_OK; 3962 inflate_codes_free(s->sub.decode.codes, z); 3963 inflate_trees_free(s->sub.decode.td, z); 3964 inflate_trees_free(s->sub.decode.tl, z); 3965 LOAD 3966 Tracev((stderr, "inflate: codes end, %lu total out\n", 3967 z->total_out + (q >= s->read ? q - s->read : 3968 (s->end - s->read) + (q - s->window)))); 3969 if (!s->last) 3970 { 3971 s->mode = TYPE; 3972 break; 3973 } 3974 if (k > 7) /* return unused byte, if any */ 3975 { 3976 Assert(k < 16, "inflate_codes grabbed too many bytes") 3977 k -= 8; 3978 n++; 3979 p--; /* can always return one */ 3980 } 3981 s->mode = DRY; 3982 case DRY: 3983 FLUSH 3984 if (s->read != s->write) 3985 LEAVE 3986 s->mode = DONEB; 3987 case DONEB: 3988 r = Z_STREAM_END; 3989 LEAVE 3990 case BADB: 3991 r = Z_DATA_ERROR; 3992 LEAVE 3993 default: 3994 r = Z_STREAM_ERROR; 3995 LEAVE 3996 } 3997} 3998 3999 4000int inflate_blocks_free(s, z, c) 4001inflate_blocks_statef *s; 4002z_streamp z; 4003uLongf *c; 4004{ 4005 inflate_blocks_reset(s, z, c); 4006 ZFREE(z, s->window); 4007 ZFREE(z, s); 4008 Trace((stderr, "inflate: blocks freed\n")); 4009 return Z_OK; 4010} 4011 4012 4013void inflate_set_dictionary(s, d, n) 4014inflate_blocks_statef *s; 4015const Bytef *d; 4016uInt n; 4017{ 4018 zmemcpy((charf *)s->window, d, n); 4019 s->read = s->write = s->window + n; 4020} 4021 4022/* 4023 * This subroutine adds the data at next_in/avail_in to the output history 4024 * without performing any output. The output buffer must be "caught up"; 4025 * i.e. no pending output (hence s->read equals s->write), and the state must 4026 * be BLOCKS (i.e. we should be willing to see the start of a series of 4027 * BLOCKS). On exit, the output will also be caught up, and the checksum 4028 * will have been updated if need be. 4029 */ 4030int inflate_addhistory(s, z) 4031inflate_blocks_statef *s; 4032z_stream *z; 4033{ 4034 uLong b; /* bit buffer */ /* NOT USED HERE */ 4035 uInt k; /* bits in bit buffer */ /* NOT USED HERE */ 4036 uInt t; /* temporary storage */ 4037 Bytef *p; /* input data pointer */ 4038 uInt n; /* bytes available there */ 4039 Bytef *q; /* output window write pointer */ 4040 uInt m; /* bytes to end of window or read pointer */ 4041 4042 if (s->read != s->write) 4043 return Z_STREAM_ERROR; 4044 if (s->mode != TYPE) 4045 return Z_DATA_ERROR; 4046 4047 /* we're ready to rock */ 4048 LOAD 4049 /* while there is input ready, copy to output buffer, moving 4050 * pointers as needed. 4051 */ 4052 while (n) { 4053 t = n; /* how many to do */ 4054 /* is there room until end of buffer? */ 4055 if (t > m) t = m; 4056 /* update check information */ 4057 if (s->checkfn != Z_NULL) 4058 s->check = (*s->checkfn)(s->check, q, t); 4059 zmemcpy(q, p, t); 4060 q += t; 4061 p += t; 4062 n -= t; 4063 z->total_out += t; 4064 s->read = q; /* drag read pointer forward */ 4065/* WWRAP */ /* expand WWRAP macro by hand to handle s->read */ 4066 if (q == s->end) { 4067 s->read = q = s->window; 4068 m = WAVAIL; 4069 } 4070 } 4071 UPDATE 4072 return Z_OK; 4073} 4074 4075 4076/* 4077 * At the end of a Deflate-compressed PPP packet, we expect to have seen 4078 * a `stored' block type value but not the (zero) length bytes. 4079 */ 4080int inflate_packet_flush(s) 4081 inflate_blocks_statef *s; 4082{ 4083 if (s->mode != LENS) 4084 return Z_DATA_ERROR; 4085 s->mode = TYPE; 4086 return Z_OK; 4087} 4088/* --- infblock.c */ 4089 4090/* +++ inftrees.c */ 4091/* inftrees.c -- generate Huffman trees for efficient decoding 4092 * Copyright (C) 1995-1996 Mark Adler 4093 * For conditions of distribution and use, see copyright notice in zlib.h 4094 */ 4095 4096/* #include "zutil.h" */ 4097/* #include "inftrees.h" */ 4098 4099char inflate_copyright[] = " inflate 1.0.4 Copyright 1995-1996 Mark Adler "; 4100/* 4101 If you use the zlib library in a product, an acknowledgment is welcome 4102 in the documentation of your product. If for some reason you cannot 4103 include such an acknowledgment, I would appreciate that you keep this 4104 copyright string in the executable of your product. 4105 */ 4106 4107#ifndef NO_DUMMY_DECL 4108struct internal_state {int dummy;}; /* for buggy compilers */ 4109#endif 4110 4111/* simplify the use of the inflate_huft type with some defines */ 4112#define base more.Base 4113#define next more.Next 4114#define exop word.what.Exop 4115#define bits word.what.Bits 4116 4117 4118local int huft_build OF(( 4119 uIntf *, /* code lengths in bits */ 4120 uInt, /* number of codes */ 4121 uInt, /* number of "simple" codes */ 4122 const uIntf *, /* list of base values for non-simple codes */ 4123 const uIntf *, /* list of extra bits for non-simple codes */ 4124 inflate_huft * FAR*,/* result: starting table */ 4125 uIntf *, /* maximum lookup bits (returns actual) */ 4126 z_streamp )); /* for zalloc function */ 4127 4128local voidpf falloc OF(( 4129 voidpf, /* opaque pointer (not used) */ 4130 uInt, /* number of items */ 4131 uInt)); /* size of item */ 4132 4133/* Tables for deflate from PKZIP's appnote.txt. */ 4134local const uInt cplens[31] = { /* Copy lengths for literal codes 257..285 */ 4135 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 4136 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0}; 4137 /* see note #13 above about 258 */ 4138local const uInt cplext[31] = { /* Extra bits for literal codes 257..285 */ 4139 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 4140 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112}; /* 112==invalid */ 4141local const uInt cpdist[30] = { /* Copy offsets for distance codes 0..29 */ 4142 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 4143 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 4144 8193, 12289, 16385, 24577}; 4145local const uInt cpdext[30] = { /* Extra bits for distance codes */ 4146 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 4147 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 4148 12, 12, 13, 13}; 4149 4150/* 4151 Huffman code decoding is performed using a multi-level table lookup. 4152 The fastest way to decode is to simply build a lookup table whose 4153 size is determined by the longest code. However, the time it takes 4154 to build this table can also be a factor if the data being decoded 4155 is not very long. The most common codes are necessarily the 4156 shortest codes, so those codes dominate the decoding time, and hence 4157 the speed. The idea is you can have a shorter table that decodes the 4158 shorter, more probable codes, and then point to subsidiary tables for 4159 the longer codes. The time it costs to decode the longer codes is 4160 then traded against the time it takes to make longer tables. 4161 4162 This results of this trade are in the variables lbits and dbits 4163 below. lbits is the number of bits the first level table for literal/ 4164 length codes can decode in one step, and dbits is the same thing for 4165 the distance codes. Subsequent tables are also less than or equal to 4166 those sizes. These values may be adjusted either when all of the 4167 codes are shorter than that, in which case the longest code length in 4168 bits is used, or when the shortest code is *longer* than the requested 4169 table size, in which case the length of the shortest code in bits is 4170 used. 4171 4172 There are two different values for the two tables, since they code a 4173 different number of possibilities each. The literal/length table 4174 codes 286 possible values, or in a flat code, a little over eight 4175 bits. The distance table codes 30 possible values, or a little less 4176 than five bits, flat. The optimum values for speed end up being 4177 about one bit more than those, so lbits is 8+1 and dbits is 5+1. 4178 The optimum values may differ though from machine to machine, and 4179 possibly even between compilers. Your mileage may vary. 4180 */ 4181 4182 4183/* If BMAX needs to be larger than 16, then h and x[] should be uLong. */ 4184#define BMAX 15 /* maximum bit length of any code */ 4185#define N_MAX 288 /* maximum number of codes in any set */ 4186 4187#ifdef DEBUG_ZLIB 4188 uInt inflate_hufts; 4189#endif 4190 4191local int huft_build(b, n, s, d, e, t, m, zs) 4192uIntf *b; /* code lengths in bits (all assumed <= BMAX) */ 4193uInt n; /* number of codes (assumed <= N_MAX) */ 4194uInt s; /* number of simple-valued codes (0..s-1) */ 4195const uIntf *d; /* list of base values for non-simple codes */ 4196const uIntf *e; /* list of extra bits for non-simple codes */ 4197inflate_huft * FAR *t; /* result: starting table */ 4198uIntf *m; /* maximum lookup bits, returns actual */ 4199z_streamp zs; /* for zalloc function */ 4200/* Given a list of code lengths and a maximum table size, make a set of 4201 tables to decode that set of codes. Return Z_OK on success, Z_BUF_ERROR 4202 if the given code set is incomplete (the tables are still built in this 4203 case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of 4204 lengths), or Z_MEM_ERROR if not enough memory. */ 4205{ 4206 4207 uInt a; /* counter for codes of length k */ 4208 uInt c[BMAX+1]; /* bit length count table */ 4209 uInt f; /* i repeats in table every f entries */ 4210 int g; /* maximum code length */ 4211 int h; /* table level */ 4212 register uInt i; /* counter, current code */ 4213 register uInt j; /* counter */ 4214 register int k; /* number of bits in current code */ 4215 int l; /* bits per table (returned in m) */ 4216 register uIntf *p; /* pointer into c[], b[], or v[] */ 4217 inflate_huft *q; /* points to current table */ 4218 struct inflate_huft_s r; /* table entry for structure assignment */ 4219 inflate_huft *u[BMAX]; /* table stack */ 4220 uInt v[N_MAX]; /* values in order of bit length */ 4221 register int w; /* bits before this table == (l * h) */ 4222 uInt x[BMAX+1]; /* bit offsets, then code stack */ 4223 uIntf *xp; /* pointer into x */ 4224 int y; /* number of dummy codes added */ 4225 uInt z; /* number of entries in current table */ 4226 4227 4228 /* Generate counts for each bit length */ 4229 p = c; 4230#define C0 *p++ = 0; 4231#define C2 C0 C0 C0 C0 4232#define C4 C2 C2 C2 C2 4233 C4 /* clear c[]--assume BMAX+1 is 16 */ 4234 p = b; i = n; 4235 do { 4236 c[*p++]++; /* assume all entries <= BMAX */ 4237 } while (--i); 4238 if (c[0] == n) /* null input--all zero length codes */ 4239 { 4240 *t = (inflate_huft *)Z_NULL; 4241 *m = 0; 4242 return Z_OK; 4243 } 4244 4245 4246 /* Find minimum and maximum length, bound *m by those */ 4247 l = *m; 4248 for (j = 1; j <= BMAX; j++) 4249 if (c[j]) 4250 break; 4251 k = j; /* minimum code length */ 4252 if ((uInt)l < j) 4253 l = j; 4254 for (i = BMAX; i; i--) 4255 if (c[i]) 4256 break; 4257 g = i; /* maximum code length */ 4258 if ((uInt)l > i) 4259 l = i; 4260 *m = l; 4261 4262 4263 /* Adjust last length count to fill out codes, if needed */ 4264 for (y = 1 << j; j < i; j++, y <<= 1) 4265 if ((y -= c[j]) < 0) 4266 return Z_DATA_ERROR; 4267 if ((y -= c[i]) < 0) 4268 return Z_DATA_ERROR; 4269 c[i] += y; 4270 4271 4272 /* Generate starting offsets into the value table for each length */ 4273 x[1] = j = 0; 4274 p = c + 1; xp = x + 2; 4275 while (--i) { /* note that i == g from above */ 4276 *xp++ = (j += *p++); 4277 } 4278 4279 4280 /* Make a table of values in order of bit lengths */ 4281 p = b; i = 0; 4282 do { 4283 if ((j = *p++) != 0) 4284 v[x[j]++] = i; 4285 } while (++i < n); 4286 n = x[g]; /* set n to length of v */ 4287 4288 4289 /* Generate the Huffman codes and for each, make the table entries */ 4290 x[0] = i = 0; /* first Huffman code is zero */ 4291 p = v; /* grab values in bit order */ 4292 h = -1; /* no tables yet--level -1 */ 4293 w = -l; /* bits decoded == (l * h) */ 4294 u[0] = (inflate_huft *)Z_NULL; /* just to keep compilers happy */ 4295 q = (inflate_huft *)Z_NULL; /* ditto */ 4296 z = 0; /* ditto */ 4297 4298 /* go through the bit lengths (k already is bits in shortest code) */ 4299 for (; k <= g; k++) 4300 { 4301 a = c[k]; 4302 while (a--) 4303 { 4304 /* here i is the Huffman code of length k bits for value *p */ 4305 /* make tables up to required level */ 4306 while (k > w + l) 4307 { 4308 h++; 4309 w += l; /* previous table always l bits */ 4310 4311 /* compute minimum size table less than or equal to l bits */ 4312 z = g - w; 4313 z = z > (uInt)l ? l : z; /* table size upper limit */ 4314 if ((f = 1 << (j = k - w)) > a + 1) /* try a k-w bit table */ 4315 { /* too few codes for k-w bit table */ 4316 f -= a + 1; /* deduct codes from patterns left */ 4317 xp = c + k; 4318 if (j < z) 4319 while (++j < z) /* try smaller tables up to z bits */ 4320 { 4321 if ((f <<= 1) <= *++xp) 4322 break; /* enough codes to use up j bits */ 4323 f -= *xp; /* else deduct codes from patterns */ 4324 } 4325 } 4326 z = 1 << j; /* table entries for j-bit table */ 4327 4328 /* allocate and link in new table */ 4329 if ((q = (inflate_huft *)ZALLOC 4330 (zs,z + 1,sizeof(inflate_huft))) == Z_NULL) 4331 { 4332 if (h) 4333 inflate_trees_free(u[0], zs); 4334 return Z_MEM_ERROR; /* not enough memory */ 4335 } 4336#ifdef DEBUG_ZLIB 4337 inflate_hufts += z + 1; 4338#endif 4339 *t = q + 1; /* link to list for huft_free() */ 4340 *(t = &(q->next)) = Z_NULL; 4341 u[h] = ++q; /* table starts after link */ 4342 4343 /* connect to last table, if there is one */ 4344 if (h) 4345 { 4346 x[h] = i; /* save pattern for backing up */ 4347 r.bits = (Byte)l; /* bits to dump before this table */ 4348 r.exop = (Byte)j; /* bits in this table */ 4349 r.next = q; /* pointer to this table */ 4350 j = i >> (w - l); /* (get around Turbo C bug) */ 4351 u[h-1][j] = r; /* connect to last table */ 4352 } 4353 } 4354 4355 /* set up table entry in r */ 4356 r.bits = (Byte)(k - w); 4357 if (p >= v + n) 4358 r.exop = 128 + 64; /* out of values--invalid code */ 4359 else if (*p < s) 4360 { 4361 r.exop = (Byte)(*p < 256 ? 0 : 32 + 64); /* 256 is end-of-block */ 4362 r.base = *p++; /* simple code is just the value */ 4363 } 4364 else 4365 { 4366 r.exop = (Byte)(e[*p - s] + 16 + 64);/* non-simple--look up in lists */ 4367 r.base = d[*p++ - s]; 4368 } 4369 4370 /* fill code-like entries with r */ 4371 f = 1 << (k - w); 4372 for (j = i >> w; j < z; j += f) 4373 q[j] = r; 4374 4375 /* backwards increment the k-bit code i */ 4376 for (j = 1 << (k - 1); i & j; j >>= 1) 4377 i ^= j; 4378 i ^= j; 4379 4380 /* backup over finished tables */ 4381 while ((i & ((1 << w) - 1)) != x[h]) 4382 { 4383 h--; /* don't need to update q */ 4384 w -= l; 4385 } 4386 } 4387 } 4388 4389 4390 /* Return Z_BUF_ERROR if we were given an incomplete table */ 4391 return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK; 4392} 4393 4394 4395int inflate_trees_bits(c, bb, tb, z) 4396uIntf *c; /* 19 code lengths */ 4397uIntf *bb; /* bits tree desired/actual depth */ 4398inflate_huft * FAR *tb; /* bits tree result */ 4399z_streamp z; /* for zfree function */ 4400{ 4401 int r; 4402 4403 r = huft_build(c, 19, 19, (uIntf*)Z_NULL, (uIntf*)Z_NULL, tb, bb, z); 4404 if (r == Z_DATA_ERROR) 4405 z->msg = (char*)"oversubscribed dynamic bit lengths tree"; 4406 else if (r == Z_BUF_ERROR || *bb == 0) 4407 { 4408 inflate_trees_free(*tb, z); 4409 z->msg = (char*)"incomplete dynamic bit lengths tree"; 4410 r = Z_DATA_ERROR; 4411 } 4412 return r; 4413} 4414 4415 4416int inflate_trees_dynamic(nl, nd, c, bl, bd, tl, td, z) 4417uInt nl; /* number of literal/length codes */ 4418uInt nd; /* number of distance codes */ 4419uIntf *c; /* that many (total) code lengths */ 4420uIntf *bl; /* literal desired/actual bit depth */ 4421uIntf *bd; /* distance desired/actual bit depth */ 4422inflate_huft * FAR *tl; /* literal/length tree result */ 4423inflate_huft * FAR *td; /* distance tree result */ 4424z_streamp z; /* for zfree function */ 4425{ 4426 int r; 4427 4428 /* build literal/length tree */ 4429 r = huft_build(c, nl, 257, cplens, cplext, tl, bl, z); 4430 if (r != Z_OK || *bl == 0) 4431 { 4432 if (r == Z_DATA_ERROR) 4433 z->msg = (char*)"oversubscribed literal/length tree"; 4434 else if (r != Z_MEM_ERROR) 4435 { 4436 inflate_trees_free(*tl, z); 4437 z->msg = (char*)"incomplete literal/length tree"; 4438 r = Z_DATA_ERROR; 4439 } 4440 return r; 4441 } 4442 4443 /* build distance tree */ 4444 r = huft_build(c + nl, nd, 0, cpdist, cpdext, td, bd, z); 4445 if (r != Z_OK || (*bd == 0 && nl > 257)) 4446 { 4447 if (r == Z_DATA_ERROR) 4448 z->msg = (char*)"oversubscribed distance tree"; 4449 else if (r == Z_BUF_ERROR) { 4450#ifdef PKZIP_BUG_WORKAROUND 4451 r = Z_OK; 4452 } 4453#else 4454 inflate_trees_free(*td, z); 4455 z->msg = (char*)"incomplete distance tree"; 4456 r = Z_DATA_ERROR; 4457 } 4458 else if (r != Z_MEM_ERROR) 4459 { 4460 z->msg = (char*)"empty distance tree with lengths"; 4461 r = Z_DATA_ERROR; 4462 } 4463 inflate_trees_free(*tl, z); 4464 return r; 4465#endif 4466 } 4467 4468 /* done */ 4469 return Z_OK; 4470} 4471 4472 4473/* build fixed tables only once--keep them here */ 4474local int fixed_built = 0; 4475#define FIXEDH 530 /* number of hufts used by fixed tables */ 4476local inflate_huft fixed_mem[FIXEDH]; 4477local uInt fixed_bl; 4478local uInt fixed_bd; 4479local inflate_huft *fixed_tl; 4480local inflate_huft *fixed_td; 4481 4482 4483local voidpf falloc(q, n, s) 4484voidpf q; /* opaque pointer */ 4485uInt n; /* number of items */ 4486uInt s; /* size of item */ 4487{ 4488 Assert(s == sizeof(inflate_huft) && n <= *(intf *)q, 4489 "inflate_trees falloc overflow"); 4490 *(intf *)q -= n+s-s; /* s-s to avoid warning */ 4491 return (voidpf)(fixed_mem + *(intf *)q); 4492} 4493 4494 4495int inflate_trees_fixed(bl, bd, tl, td) 4496uIntf *bl; /* literal desired/actual bit depth */ 4497uIntf *bd; /* distance desired/actual bit depth */ 4498inflate_huft * FAR *tl; /* literal/length tree result */ 4499inflate_huft * FAR *td; /* distance tree result */ 4500{ 4501 /* build fixed tables if not already (multiple overlapped executions ok) */ 4502 if (!fixed_built) 4503 { 4504 int k; /* temporary variable */ 4505 unsigned c[288]; /* length list for huft_build */ 4506 z_stream z; /* for falloc function */ 4507 int f = FIXEDH; /* number of hufts left in fixed_mem */ 4508 4509 /* set up fake z_stream for memory routines */ 4510 z.zalloc = falloc; 4511 z.zfree = Z_NULL; 4512 z.opaque = (voidpf)&f; 4513 4514 /* literal table */ 4515 for (k = 0; k < 144; k++) 4516 c[k] = 8; 4517 for (; k < 256; k++) 4518 c[k] = 9; 4519 for (; k < 280; k++) 4520 c[k] = 7; 4521 for (; k < 288; k++) 4522 c[k] = 8; 4523 fixed_bl = 7; 4524 huft_build(c, 288, 257, cplens, cplext, &fixed_tl, &fixed_bl, &z); 4525 4526 /* distance table */ 4527 for (k = 0; k < 30; k++) 4528 c[k] = 5; 4529 fixed_bd = 5; 4530 huft_build(c, 30, 0, cpdist, cpdext, &fixed_td, &fixed_bd, &z); 4531 4532 /* done */ 4533 Assert(f == 0, "invalid build of fixed tables"); 4534 fixed_built = 1; 4535 } 4536 *bl = fixed_bl; 4537 *bd = fixed_bd; 4538 *tl = fixed_tl; 4539 *td = fixed_td; 4540 return Z_OK; 4541} 4542 4543 4544int inflate_trees_free(t, z) 4545inflate_huft *t; /* table to free */ 4546z_streamp z; /* for zfree function */ 4547/* Free the malloc'ed tables built by huft_build(), which makes a linked 4548 list of the tables it made, with the links in a dummy first entry of 4549 each table. */ 4550{ 4551 register inflate_huft *p, *q, *r; 4552 4553 /* Reverse linked list */ 4554 p = Z_NULL; 4555 q = t; 4556 while (q != Z_NULL) 4557 { 4558 r = (q - 1)->next; 4559 (q - 1)->next = p; 4560 p = q; 4561 q = r; 4562 } 4563 /* Go through linked list, freeing from the malloced (t[-1]) address. */ 4564 while (p != Z_NULL) 4565 { 4566 q = (--p)->next; 4567 ZFREE(z,p); 4568 p = q; 4569 } 4570 return Z_OK; 4571} 4572/* --- inftrees.c */ 4573 4574/* +++ infcodes.c */ 4575/* infcodes.c -- process literals and length/distance pairs 4576 * Copyright (C) 1995-1996 Mark Adler 4577 * For conditions of distribution and use, see copyright notice in zlib.h 4578 */ 4579 4580/* #include "zutil.h" */ 4581/* #include "inftrees.h" */ 4582/* #include "infblock.h" */ 4583/* #include "infcodes.h" */ 4584/* #include "infutil.h" */ 4585 4586/* +++ inffast.h */ 4587/* inffast.h -- header to use inffast.c 4588 * Copyright (C) 1995-1996 Mark Adler 4589 * For conditions of distribution and use, see copyright notice in zlib.h 4590 */ 4591 4592/* WARNING: this file should *not* be used by applications. It is 4593 part of the implementation of the compression library and is 4594 subject to change. Applications should only use zlib.h. 4595 */ 4596 4597extern int inflate_fast OF(( 4598 uInt, 4599 uInt, 4600 inflate_huft *, 4601 inflate_huft *, 4602 inflate_blocks_statef *, 4603 z_streamp )); 4604/* --- inffast.h */ 4605 4606/* simplify the use of the inflate_huft type with some defines */ 4607#define base more.Base 4608#define next more.Next 4609#define exop word.what.Exop 4610#define bits word.what.Bits 4611 4612/* inflate codes private state */ 4613struct inflate_codes_state { 4614 4615 /* mode */ 4616 enum { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ 4617 START, /* x: set up for LEN */ 4618 LEN, /* i: get length/literal/eob next */ 4619 LENEXT, /* i: getting length extra (have base) */ 4620 DIST, /* i: get distance next */ 4621 DISTEXT, /* i: getting distance extra */ 4622 COPY, /* o: copying bytes in window, waiting for space */ 4623 LIT, /* o: got literal, waiting for output space */ 4624 WASH, /* o: got eob, possibly still output waiting */ 4625 END, /* x: got eob and all data flushed */ 4626 BADCODE} /* x: got error */ 4627 mode; /* current inflate_codes mode */ 4628 4629 /* mode dependent information */ 4630 uInt len; 4631 union { 4632 struct { 4633 inflate_huft *tree; /* pointer into tree */ 4634 uInt need; /* bits needed */ 4635 } code; /* if LEN or DIST, where in tree */ 4636 uInt lit; /* if LIT, literal */ 4637 struct { 4638 uInt get; /* bits to get for extra */ 4639 uInt dist; /* distance back to copy from */ 4640 } copy; /* if EXT or COPY, where and how much */ 4641 } sub; /* submode */ 4642 4643 /* mode independent information */ 4644 Byte lbits; /* ltree bits decoded per branch */ 4645 Byte dbits; /* dtree bits decoder per branch */ 4646 inflate_huft *ltree; /* literal/length/eob tree */ 4647 inflate_huft *dtree; /* distance tree */ 4648 4649}; 4650 4651 4652inflate_codes_statef *inflate_codes_new(bl, bd, tl, td, z) 4653uInt bl, bd; 4654inflate_huft *tl; 4655inflate_huft *td; /* need separate declaration for Borland C++ */ 4656z_streamp z; 4657{ 4658 inflate_codes_statef *c; 4659 4660 if ((c = (inflate_codes_statef *) 4661 ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL) 4662 { 4663 c->mode = START; 4664 c->lbits = (Byte)bl; 4665 c->dbits = (Byte)bd; 4666 c->ltree = tl; 4667 c->dtree = td; 4668 Tracev((stderr, "inflate: codes new\n")); 4669 } 4670 return c; 4671} 4672 4673 4674int inflate_codes(s, z, r) 4675inflate_blocks_statef *s; 4676z_streamp z; 4677int r; 4678{ 4679 uInt j; /* temporary storage */ 4680 inflate_huft *t; /* temporary pointer */ 4681 uInt e; /* extra bits or operation */ 4682 uLong b; /* bit buffer */ 4683 uInt k; /* bits in bit buffer */ 4684 Bytef *p; /* input data pointer */ 4685 uInt n; /* bytes available there */ 4686 Bytef *q; /* output window write pointer */ 4687 uInt m; /* bytes to end of window or read pointer */ 4688 Bytef *f; /* pointer to copy strings from */ 4689 inflate_codes_statef *c = s->sub.decode.codes; /* codes state */ 4690 4691 /* copy input/output information to locals (UPDATE macro restores) */ 4692 LOAD 4693 4694 /* process input and output based on current state */ 4695 while (1) switch (c->mode) 4696 { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */ 4697 case START: /* x: set up for LEN */ 4698#ifndef SLOW 4699 if (m >= 258 && n >= 10) 4700 { 4701 UPDATE 4702 r = inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z); 4703 LOAD 4704 if (r != Z_OK) 4705 { 4706 c->mode = r == Z_STREAM_END ? WASH : BADCODE; 4707 break; 4708 } 4709 } 4710#endif /* !SLOW */ 4711 c->sub.code.need = c->lbits; 4712 c->sub.code.tree = c->ltree; 4713 c->mode = LEN; 4714 case LEN: /* i: get length/literal/eob next */ 4715 j = c->sub.code.need; 4716 NEEDBITS(j) 4717 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); 4718 DUMPBITS(t->bits) 4719 e = (uInt)(t->exop); 4720 if (e == 0) /* literal */ 4721 { 4722 c->sub.lit = t->base; 4723 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 4724 "inflate: literal '%c'\n" : 4725 "inflate: literal 0x%02x\n", t->base)); 4726 c->mode = LIT; 4727 break; 4728 } 4729 if (e & 16) /* length */ 4730 { 4731 c->sub.copy.get = e & 15; 4732 c->len = t->base; 4733 c->mode = LENEXT; 4734 break; 4735 } 4736 if ((e & 64) == 0) /* next table */ 4737 { 4738 c->sub.code.need = e; 4739 c->sub.code.tree = t->next; 4740 break; 4741 } 4742 if (e & 32) /* end of block */ 4743 { 4744 Tracevv((stderr, "inflate: end of block\n")); 4745 c->mode = WASH; 4746 break; 4747 } 4748 c->mode = BADCODE; /* invalid code */ 4749 z->msg = (char*)"invalid literal/length code"; 4750 r = Z_DATA_ERROR; 4751 LEAVE 4752 case LENEXT: /* i: getting length extra (have base) */ 4753 j = c->sub.copy.get; 4754 NEEDBITS(j) 4755 c->len += (uInt)b & inflate_mask[j]; 4756 DUMPBITS(j) 4757 c->sub.code.need = c->dbits; 4758 c->sub.code.tree = c->dtree; 4759 Tracevv((stderr, "inflate: length %u\n", c->len)); 4760 c->mode = DIST; 4761 case DIST: /* i: get distance next */ 4762 j = c->sub.code.need; 4763 NEEDBITS(j) 4764 t = c->sub.code.tree + ((uInt)b & inflate_mask[j]); 4765 DUMPBITS(t->bits) 4766 e = (uInt)(t->exop); 4767 if (e & 16) /* distance */ 4768 { 4769 c->sub.copy.get = e & 15; 4770 c->sub.copy.dist = t->base; 4771 c->mode = DISTEXT; 4772 break; 4773 } 4774 if ((e & 64) == 0) /* next table */ 4775 { 4776 c->sub.code.need = e; 4777 c->sub.code.tree = t->next; 4778 break; 4779 } 4780 c->mode = BADCODE; /* invalid code */ 4781 z->msg = (char*)"invalid distance code"; 4782 r = Z_DATA_ERROR; 4783 LEAVE 4784 case DISTEXT: /* i: getting distance extra */ 4785 j = c->sub.copy.get; 4786 NEEDBITS(j) 4787 c->sub.copy.dist += (uInt)b & inflate_mask[j]; 4788 DUMPBITS(j) 4789 Tracevv((stderr, "inflate: distance %u\n", c->sub.copy.dist)); 4790 c->mode = COPY; 4791 case COPY: /* o: copying bytes in window, waiting for space */ 4792#ifndef __TURBOC__ /* Turbo C bug for following expression */ 4793 f = (uInt)(q - s->window) < c->sub.copy.dist ? 4794 s->end - (c->sub.copy.dist - (q - s->window)) : 4795 q - c->sub.copy.dist; 4796#else 4797 f = q - c->sub.copy.dist; 4798 if ((uInt)(q - s->window) < c->sub.copy.dist) 4799 f = s->end - (c->sub.copy.dist - (uInt)(q - s->window)); 4800#endif 4801 while (c->len) 4802 { 4803 NEEDOUT 4804 OUTBYTE(*f++) 4805 if (f == s->end) 4806 f = s->window; 4807 c->len--; 4808 } 4809 c->mode = START; 4810 break; 4811 case LIT: /* o: got literal, waiting for output space */ 4812 NEEDOUT 4813 OUTBYTE(c->sub.lit) 4814 c->mode = START; 4815 break; 4816 case WASH: /* o: got eob, possibly more output */ 4817 FLUSH 4818 if (s->read != s->write) 4819 LEAVE 4820 c->mode = END; 4821 case END: 4822 r = Z_STREAM_END; 4823 LEAVE 4824 case BADCODE: /* x: got error */ 4825 r = Z_DATA_ERROR; 4826 LEAVE 4827 default: 4828 r = Z_STREAM_ERROR; 4829 LEAVE 4830 } 4831} 4832 4833 4834void inflate_codes_free(c, z) 4835inflate_codes_statef *c; 4836z_streamp z; 4837{ 4838 ZFREE(z, c); 4839 Tracev((stderr, "inflate: codes free\n")); 4840} 4841/* --- infcodes.c */ 4842 4843/* +++ infutil.c */ 4844/* inflate_util.c -- data and routines common to blocks and codes 4845 * Copyright (C) 1995-1996 Mark Adler 4846 * For conditions of distribution and use, see copyright notice in zlib.h 4847 */ 4848 4849/* #include "zutil.h" */ 4850/* #include "infblock.h" */ 4851/* #include "inftrees.h" */ 4852/* #include "infcodes.h" */ 4853/* #include "infutil.h" */ 4854 4855#ifndef NO_DUMMY_DECL 4856struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 4857#endif 4858 4859/* And'ing with mask[n] masks the lower n bits */ 4860uInt inflate_mask[17] = { 4861 0x0000, 4862 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, 4863 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff 4864}; 4865 4866 4867/* copy as much as possible from the sliding window to the output area */ 4868int inflate_flush(s, z, r) 4869inflate_blocks_statef *s; 4870z_streamp z; 4871int r; 4872{ 4873 uInt n; 4874 Bytef *p; 4875 Bytef *q; 4876 4877 /* local copies of source and destination pointers */ 4878 p = z->next_out; 4879 q = s->read; 4880 4881 /* compute number of bytes to copy as far as end of window */ 4882 n = (uInt)((q <= s->write ? s->write : s->end) - q); 4883 if (n > z->avail_out) n = z->avail_out; 4884 if (n && r == Z_BUF_ERROR) r = Z_OK; 4885 4886 /* update counters */ 4887 z->avail_out -= n; 4888 z->total_out += n; 4889 4890 /* update check information */ 4891 if (s->checkfn != Z_NULL) 4892 z->adler = s->check = (*s->checkfn)(s->check, q, n); 4893 4894 /* copy as far as end of window */ 4895 if (p != Z_NULL) { 4896 zmemcpy(p, q, n); 4897 p += n; 4898 } 4899 q += n; 4900 4901 /* see if more to copy at beginning of window */ 4902 if (q == s->end) 4903 { 4904 /* wrap pointers */ 4905 q = s->window; 4906 if (s->write == s->end) 4907 s->write = s->window; 4908 4909 /* compute bytes to copy */ 4910 n = (uInt)(s->write - q); 4911 if (n > z->avail_out) n = z->avail_out; 4912 if (n && r == Z_BUF_ERROR) r = Z_OK; 4913 4914 /* update counters */ 4915 z->avail_out -= n; 4916 z->total_out += n; 4917 4918 /* update check information */ 4919 if (s->checkfn != Z_NULL) 4920 z->adler = s->check = (*s->checkfn)(s->check, q, n); 4921 4922 /* copy */ 4923 if (p != Z_NULL) { 4924 zmemcpy(p, q, n); 4925 p += n; 4926 } 4927 q += n; 4928 } 4929 4930 /* update pointers */ 4931 z->next_out = p; 4932 s->read = q; 4933 4934 /* done */ 4935 return r; 4936} 4937/* --- infutil.c */ 4938 4939/* +++ inffast.c */ 4940/* inffast.c -- process literals and length/distance pairs fast 4941 * Copyright (C) 1995-1996 Mark Adler 4942 * For conditions of distribution and use, see copyright notice in zlib.h 4943 */ 4944 4945/* #include "zutil.h" */ 4946/* #include "inftrees.h" */ 4947/* #include "infblock.h" */ 4948/* #include "infcodes.h" */ 4949/* #include "infutil.h" */ 4950/* #include "inffast.h" */ 4951 4952#ifndef NO_DUMMY_DECL 4953struct inflate_codes_state {int dummy;}; /* for buggy compilers */ 4954#endif 4955 4956/* simplify the use of the inflate_huft type with some defines */ 4957#define base more.Base 4958#define next more.Next 4959#define exop word.what.Exop 4960#define bits word.what.Bits 4961 4962/* macros for bit input with no checking and for returning unused bytes */ 4963#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}} 4964#define UNGRAB {n+=(c=k>>3);p-=c;k&=7;} 4965 4966/* Called with number of bytes left to write in window at least 258 4967 (the maximum string length) and number of input bytes available 4968 at least ten. The ten bytes are six bytes for the longest length/ 4969 distance pair plus four bytes for overloading the bit buffer. */ 4970 4971int inflate_fast(bl, bd, tl, td, s, z) 4972uInt bl, bd; 4973inflate_huft *tl; 4974inflate_huft *td; /* need separate declaration for Borland C++ */ 4975inflate_blocks_statef *s; 4976z_streamp z; 4977{ 4978 inflate_huft *t; /* temporary pointer */ 4979 uInt e; /* extra bits or operation */ 4980 uLong b; /* bit buffer */ 4981 uInt k; /* bits in bit buffer */ 4982 Bytef *p; /* input data pointer */ 4983 uInt n; /* bytes available there */ 4984 Bytef *q; /* output window write pointer */ 4985 uInt m; /* bytes to end of window or read pointer */ 4986 uInt ml; /* mask for literal/length tree */ 4987 uInt md; /* mask for distance tree */ 4988 uInt c; /* bytes to copy */ 4989 uInt d; /* distance back to copy from */ 4990 Bytef *r; /* copy source pointer */ 4991 4992 /* load input, output, bit values */ 4993 LOAD 4994 4995 /* initialize masks */ 4996 ml = inflate_mask[bl]; 4997 md = inflate_mask[bd]; 4998 4999 /* do until not enough input or output space for fast loop */ 5000 do { /* assume called with m >= 258 && n >= 10 */ 5001 /* get literal/length code */ 5002 GRABBITS(20) /* max bits for literal/length code */ 5003 if ((e = (t = tl + ((uInt)b & ml))->exop) == 0) 5004 { 5005 DUMPBITS(t->bits) 5006 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 5007 "inflate: * literal '%c'\n" : 5008 "inflate: * literal 0x%02x\n", t->base)); 5009 *q++ = (Byte)t->base; 5010 m--; 5011 continue; 5012 } 5013 do { 5014 DUMPBITS(t->bits) 5015 if (e & 16) 5016 { 5017 /* get extra bits for length */ 5018 e &= 15; 5019 c = t->base + ((uInt)b & inflate_mask[e]); 5020 DUMPBITS(e) 5021 Tracevv((stderr, "inflate: * length %u\n", c)); 5022 5023 /* decode distance base of block to copy */ 5024 GRABBITS(15); /* max bits for distance code */ 5025 e = (t = td + ((uInt)b & md))->exop; 5026 do { 5027 DUMPBITS(t->bits) 5028 if (e & 16) 5029 { 5030 /* get extra bits to add to distance base */ 5031 e &= 15; 5032 GRABBITS(e) /* get extra bits (up to 13) */ 5033 d = t->base + ((uInt)b & inflate_mask[e]); 5034 DUMPBITS(e) 5035 Tracevv((stderr, "inflate: * distance %u\n", d)); 5036 5037 /* do the copy */ 5038 m -= c; 5039 if ((uInt)(q - s->window) >= d) /* offset before dest */ 5040 { /* just copy */ 5041 r = q - d; 5042 *q++ = *r++; c--; /* minimum count is three, */ 5043 *q++ = *r++; c--; /* so unroll loop a little */ 5044 } 5045 else /* else offset after destination */ 5046 { 5047 e = d - (uInt)(q - s->window); /* bytes from offset to end */ 5048 r = s->end - e; /* pointer to offset */ 5049 if (c > e) /* if source crosses, */ 5050 { 5051 c -= e; /* copy to end of window */ 5052 do { 5053 *q++ = *r++; 5054 } while (--e); 5055 r = s->window; /* copy rest from start of window */ 5056 } 5057 } 5058 do { /* copy all or what's left */ 5059 *q++ = *r++; 5060 } while (--c); 5061 break; 5062 } 5063 else if ((e & 64) == 0) 5064 e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop; 5065 else 5066 { 5067 z->msg = (char*)"invalid distance code"; 5068 UNGRAB 5069 UPDATE 5070 return Z_DATA_ERROR; 5071 } 5072 } while (1); 5073 break; 5074 } 5075 if ((e & 64) == 0) 5076 { 5077 if ((e = (t = t->next + ((uInt)b & inflate_mask[e]))->exop) == 0) 5078 { 5079 DUMPBITS(t->bits) 5080 Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? 5081 "inflate: * literal '%c'\n" : 5082 "inflate: * literal 0x%02x\n", t->base)); 5083 *q++ = (Byte)t->base; 5084 m--; 5085 break; 5086 } 5087 } 5088 else if (e & 32) 5089 { 5090 Tracevv((stderr, "inflate: * end of block\n")); 5091 UNGRAB 5092 UPDATE 5093 return Z_STREAM_END; 5094 } 5095 else 5096 { 5097 z->msg = (char*)"invalid literal/length code"; 5098 UNGRAB 5099 UPDATE 5100 return Z_DATA_ERROR; 5101 } 5102 } while (1); 5103 } while (m >= 258 && n >= 10); 5104 5105 /* not enough input or output--restore pointers and return */ 5106 UNGRAB 5107 UPDATE 5108 return Z_OK; 5109} 5110/* --- inffast.c */ 5111 5112/* +++ zutil.c */ 5113/* zutil.c -- target dependent utility functions for the compression library 5114 * Copyright (C) 1995-1996 Jean-loup Gailly. 5115 * For conditions of distribution and use, see copyright notice in zlib.h 5116 */ 5117 5118/* From: zutil.c,v 1.17 1996/07/24 13:41:12 me Exp $ */ 5119 5120#ifdef DEBUG_ZLIB 5121#include <stdio.h> 5122#endif 5123 5124/* #include "zutil.h" */ 5125 5126#ifndef NO_DUMMY_DECL 5127struct internal_state {int dummy;}; /* for buggy compilers */ 5128#endif 5129 5130#ifndef STDC 5131extern void exit OF((int)); 5132#endif 5133 5134static const char *z_errmsg[10] = { 5135"need dictionary", /* Z_NEED_DICT 2 */ 5136"stream end", /* Z_STREAM_END 1 */ 5137"", /* Z_OK 0 */ 5138"file error", /* Z_ERRNO (-1) */ 5139"stream error", /* Z_STREAM_ERROR (-2) */ 5140"data error", /* Z_DATA_ERROR (-3) */ 5141"insufficient memory", /* Z_MEM_ERROR (-4) */ 5142"buffer error", /* Z_BUF_ERROR (-5) */ 5143"incompatible version",/* Z_VERSION_ERROR (-6) */ 5144""}; 5145 5146 5147const char *zlibVersion() 5148{ 5149 return ZLIB_VERSION; 5150} 5151 5152#ifdef DEBUG_ZLIB 5153void z_error (m) 5154 char *m; 5155{ 5156 fprintf(stderr, "%s\n", m); 5157 exit(1); 5158} 5159#endif 5160 5161#ifndef HAVE_MEMCPY 5162 5163void zmemcpy(dest, source, len) 5164 Bytef* dest; 5165 Bytef* source; 5166 uInt len; 5167{ 5168 if (len == 0) return; 5169 do { 5170 *dest++ = *source++; /* ??? to be unrolled */ 5171 } while (--len != 0); 5172} 5173 5174int zmemcmp(s1, s2, len) 5175 Bytef* s1; 5176 Bytef* s2; 5177 uInt len; 5178{ 5179 uInt j; 5180 5181 for (j = 0; j < len; j++) { 5182 if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1; 5183 } 5184 return 0; 5185} 5186 5187void zmemzero(dest, len) 5188 Bytef* dest; 5189 uInt len; 5190{ 5191 if (len == 0) return; 5192 do { 5193 *dest++ = 0; /* ??? to be unrolled */ 5194 } while (--len != 0); 5195} 5196#endif 5197 5198#ifdef __TURBOC__ 5199#if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__) 5200/* Small and medium model in Turbo C are for now limited to near allocation 5201 * with reduced MAX_WBITS and MAX_MEM_LEVEL 5202 */ 5203# define MY_ZCALLOC 5204 5205/* Turbo C malloc() does not allow dynamic allocation of 64K bytes 5206 * and farmalloc(64K) returns a pointer with an offset of 8, so we 5207 * must fix the pointer. Warning: the pointer must be put back to its 5208 * original form in order to free it, use zcfree(). 5209 */ 5210 5211#define MAX_PTR 10 5212/* 10*64K = 640K */ 5213 5214local int next_ptr = 0; 5215 5216typedef struct ptr_table_s { 5217 voidpf org_ptr; 5218 voidpf new_ptr; 5219} ptr_table; 5220 5221local ptr_table table[MAX_PTR]; 5222/* This table is used to remember the original form of pointers 5223 * to large buffers (64K). Such pointers are normalized with a zero offset. 5224 * Since MSDOS is not a preemptive multitasking OS, this table is not 5225 * protected from concurrent access. This hack doesn't work anyway on 5226 * a protected system like OS/2. Use Microsoft C instead. 5227 */ 5228 5229voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) 5230{ 5231 voidpf buf = opaque; /* just to make some compilers happy */ 5232 ulg bsize = (ulg)items*size; 5233 5234 /* If we allocate less than 65520 bytes, we assume that farmalloc 5235 * will return a usable pointer which doesn't have to be normalized. 5236 */ 5237 if (bsize < 65520L) { 5238 buf = farmalloc(bsize); 5239 if (*(ush*)&buf != 0) return buf; 5240 } else { 5241 buf = farmalloc(bsize + 16L); 5242 } 5243 if (buf == NULL || next_ptr >= MAX_PTR) return NULL; 5244 table[next_ptr].org_ptr = buf; 5245 5246 /* Normalize the pointer to seg:0 */ 5247 *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4; 5248 *(ush*)&buf = 0; 5249 table[next_ptr++].new_ptr = buf; 5250 return buf; 5251} 5252 5253void zcfree (voidpf opaque, voidpf ptr) 5254{ 5255 int n; 5256 if (*(ush*)&ptr != 0) { /* object < 64K */ 5257 farfree(ptr); 5258 return; 5259 } 5260 /* Find the original pointer */ 5261 for (n = 0; n < next_ptr; n++) { 5262 if (ptr != table[n].new_ptr) continue; 5263 5264 farfree(table[n].org_ptr); 5265 while (++n < next_ptr) { 5266 table[n-1] = table[n]; 5267 } 5268 next_ptr--; 5269 return; 5270 } 5271 ptr = opaque; /* just to make some compilers happy */ 5272 Assert(0, "zcfree: ptr not found"); 5273} 5274#endif 5275#endif /* __TURBOC__ */ 5276 5277 5278#if defined(M_I86) && !defined(__32BIT__) 5279/* Microsoft C in 16-bit mode */ 5280 5281# define MY_ZCALLOC 5282 5283#if (!defined(_MSC_VER) || (_MSC_VER < 600)) 5284# define _halloc halloc 5285# define _hfree hfree 5286#endif 5287 5288voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) 5289{ 5290 if (opaque) opaque = 0; /* to make compiler happy */ 5291 return _halloc((long)items, size); 5292} 5293 5294void zcfree (voidpf opaque, voidpf ptr) 5295{ 5296 if (opaque) opaque = 0; /* to make compiler happy */ 5297 _hfree(ptr); 5298} 5299 5300#endif /* MSC */ 5301 5302 5303#ifndef MY_ZCALLOC /* Any system without a special alloc function */ 5304 5305#ifndef STDC 5306extern voidp calloc OF((uInt items, uInt size)); 5307extern void free OF((voidpf ptr)); 5308#endif 5309 5310voidpf zcalloc (opaque, items, size) 5311 voidpf opaque; 5312 unsigned items; 5313 unsigned size; 5314{ 5315 if (opaque) items += size - size; /* make compiler happy */ 5316 return (voidpf)calloc(items, size); 5317} 5318 5319void zcfree (opaque, ptr) 5320 voidpf opaque; 5321 voidpf ptr; 5322{ 5323 free(ptr); 5324 if (opaque) return; /* make compiler happy */ 5325} 5326 5327#endif /* MY_ZCALLOC */ 5328/* --- zutil.c */ 5329 5330/* +++ adler32.c */ 5331/* adler32.c -- compute the Adler-32 checksum of a data stream 5332 * Copyright (C) 1995-1996 Mark Adler 5333 * For conditions of distribution and use, see copyright notice in zlib.h 5334 */ 5335 5336/* From: adler32.c,v 1.10 1996/05/22 11:52:18 me Exp $ */ 5337 5338/* #include "zlib.h" */ 5339 5340#define BASE 65521L /* largest prime smaller than 65536 */ 5341#define NMAX 5552 5342/* NMAX is the largest n such that 255n(n+1)/2 + (n+1)(BASE-1) <= 2^32-1 */ 5343 5344#define DO1(buf,i) {s1 += buf[i]; s2 += s1;} 5345#define DO2(buf,i) DO1(buf,i); DO1(buf,i+1); 5346#define DO4(buf,i) DO2(buf,i); DO2(buf,i+2); 5347#define DO8(buf,i) DO4(buf,i); DO4(buf,i+4); 5348#define DO16(buf) DO8(buf,0); DO8(buf,8); 5349 5350/* ========================================================================= */ 5351uLong adler32(adler, buf, len) 5352 uLong adler; 5353 const Bytef *buf; 5354 uInt len; 5355{ 5356 unsigned long s1 = adler & 0xffff; 5357 unsigned long s2 = (adler >> 16) & 0xffff; 5358 int k; 5359 5360 if (buf == Z_NULL) return 1L; 5361 5362 while (len > 0) { 5363 k = len < NMAX ? len : NMAX; 5364 len -= k; 5365 while (k >= 16) { 5366 DO16(buf); 5367 buf += 16; 5368 k -= 16; 5369 } 5370 if (k != 0) do { 5371 s1 += *buf++; 5372 s2 += s1; 5373 } while (--k); 5374 s1 %= BASE; 5375 s2 %= BASE; 5376 } 5377 return (s2 << 16) | s1; 5378} 5379/* --- adler32.c */
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