1 /* trees.c -- output deflated data using Huffman coding 2 * Copyright (C) 1995-2012 Jean-loup Gailly 3 * detect_data_type() function provided freely by Cosmin Truta, 2006 4 * For conditions of distribution and use, see copyright notice in zlib.h 5 */ 6 7 /* 8 * ALGORITHM 9 * 10 * The "deflation" process uses several Huffman trees. The more 11 * common source values are represented by shorter bit sequences. 12 * 13 * Each code tree is stored in a compressed form which is itself 14 * a Huffman encoding of the lengths of all the code strings (in 15 * ascending order by source values). The actual code strings are 16 * reconstructed from the lengths in the inflate process, as described 17 * in the deflate specification. 18 * 19 * REFERENCES 20 * 21 * Deutsch, L.P.,"'Deflate' Compressed Data Format Specification". 22 * Available in ftp.uu.net:/pub/archiving/zip/doc/deflate-1.1.doc 23 * 24 * Storer, James A. 25 * Data Compression: Methods and Theory, pp. 49-50. 26 * Computer Science Press, 1988. ISBN 0-7167-8156-5. 27 * 28 * Sedgewick, R. 29 * Algorithms, p290. 30 * Addison-Wesley, 1983. ISBN 0-201-06672-6. 31 */ 32 33 /* @(#) $Id$ */ 34 35 /* #define GEN_TREES_H */ 36 37 #include "hammer2_zlib_deflate.h" 38 39 #ifdef H2_ZLIB_DEBUG 40 # include <ctype.h> 41 #endif 42 43 /* =========================================================================== 44 * Constants 45 */ 46 47 #define MAX_BL_BITS 7 48 /* Bit length codes must not exceed MAX_BL_BITS bits */ 49 50 #define END_BLOCK 256 51 /* end of block literal code */ 52 53 #define REP_3_6 16 54 /* repeat previous bit length 3-6 times (2 bits of repeat count) */ 55 56 #define REPZ_3_10 17 57 /* repeat a zero length 3-10 times (3 bits of repeat count) */ 58 59 #define REPZ_11_138 18 60 /* repeat a zero length 11-138 times (7 bits of repeat count) */ 61 62 local const int extra_lbits[LENGTH_CODES] /* extra bits for each length code */ 63 = {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}; 64 65 local const int extra_dbits[D_CODES] /* extra bits for each distance code */ 66 = {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}; 67 68 local const int extra_blbits[BL_CODES]/* extra bits for each bit length code */ 69 = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7}; 70 71 local const uch bl_order[BL_CODES] 72 = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15}; 73 /* The lengths of the bit length codes are sent in order of decreasing 74 * probability, to avoid transmitting the lengths for unused bit length codes. 75 */ 76 77 /* =========================================================================== 78 * Local data. These are initialized only once. 79 */ 80 81 #define DIST_CODE_LEN 512 /* see definition of array dist_code below */ 82 83 #if defined(GEN_TREES_H) || !defined(STDC) 84 /* non ANSI compilers may not accept trees.h */ 85 86 local ct_data static_ltree[L_CODES+2]; 87 /* The static literal tree. Since the bit lengths are imposed, there is no 88 * need for the L_CODES extra codes used during heap construction. However 89 * The codes 286 and 287 are needed to build a canonical tree (see _tr_init 90 * below). 91 */ 92 93 local ct_data static_dtree[D_CODES]; 94 /* The static distance tree. (Actually a trivial tree since all codes use 95 * 5 bits.) 96 */ 97 98 uch _dist_code[DIST_CODE_LEN]; 99 /* Distance codes. The first 256 values correspond to the distances 100 * 3 .. 258, the last 256 values correspond to the top 8 bits of 101 * the 15 bit distances. 102 */ 103 104 uch _length_code[MAX_MATCH-MIN_MATCH+1]; 105 /* length code for each normalized match length (0 == MIN_MATCH) */ 106 107 local int base_length[LENGTH_CODES]; 108 /* First normalized length for each code (0 = MIN_MATCH) */ 109 110 local int base_dist[D_CODES]; 111 /* First normalized distance for each code (0 = distance of 1) */ 112 113 #else 114 # include "hammer2_zlib_trees.h" 115 #endif /* GEN_TREES_H */ 116 117 struct static_tree_desc_s { 118 const ct_data *static_tree; /* static tree or NULL */ 119 const intf *extra_bits; /* extra bits for each code or NULL */ 120 int extra_base; /* base index for extra_bits */ 121 int elems; /* max number of elements in the tree */ 122 int max_length; /* max bit length for the codes */ 123 }; 124 125 local static_tree_desc static_l_desc = 126 {static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS}; 127 128 local static_tree_desc static_d_desc = 129 {static_dtree, extra_dbits, 0, D_CODES, MAX_BITS}; 130 131 local static_tree_desc static_bl_desc = 132 {(const ct_data *)0, extra_blbits, 0, BL_CODES, MAX_BL_BITS}; 133 134 /* =========================================================================== 135 * Local (static) routines in this file. 136 */ 137 138 local void tr_static_init (void); 139 local void init_block (deflate_state *s); 140 local void pqdownheap (deflate_state *s, ct_data *tree, int k); 141 local void gen_bitlen (deflate_state *s, tree_desc *desc); 142 local void gen_codes (ct_data *tree, int max_code, ushf *bl_count); 143 local void build_tree (deflate_state *s, tree_desc *desc); 144 local void scan_tree (deflate_state *s, ct_data *tree, int max_code); 145 local void send_tree (deflate_state *s, ct_data *tree, int max_code); 146 local int build_bl_tree (deflate_state *s); 147 local void send_all_trees (deflate_state *s, int lcodes, int dcodes, 148 int blcodes); 149 local void compress_block (deflate_state *s, const ct_data *ltree, 150 const ct_data *dtree); 151 local int detect_data_type (deflate_state *s); 152 local unsigned bi_reverse (unsigned value, int length); 153 local void bi_windup (deflate_state *s); 154 local void bi_flush (deflate_state *s); 155 local void copy_block (deflate_state *s, charf *buf, unsigned len, 156 int header); 157 158 #ifdef GEN_TREES_H 159 local void gen_trees_header (void); 160 #endif 161 162 #ifndef H2_ZLIB_DEBUG 163 # define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len) 164 /* Send a code of the given tree. c and tree must not have side effects */ 165 166 #else /* H2_ZLIB_DEBUG */ 167 # define send_code(s, c, tree) \ 168 { if (z_verbose>2) fprintf(stderr,"\ncd %3d ",(c)); \ 169 send_bits(s, tree[c].Code, tree[c].Len); } 170 #endif 171 172 /* =========================================================================== 173 * Output a short LSB first on the stream. 174 * IN assertion: there is enough room in pendingBuf. 175 */ 176 #define put_short(s, w) { \ 177 put_byte(s, (uch)((w) & 0xff)); \ 178 put_byte(s, (uch)((ush)(w) >> 8)); \ 179 } 180 181 /* =========================================================================== 182 * Send a value on a given number of bits. 183 * IN assertion: length <= 16 and value fits in length bits. 184 */ 185 #ifdef H2_ZLIB_DEBUG 186 local void send_bits (deflate_state *s, int value, int length); 187 188 local 189 void 190 send_bits(deflate_state *s, int value, int length) 191 { 192 Tracevv((stderr," l %2d v %4x ", length, value)); 193 Assert(length > 0 && length <= 15, "invalid length"); 194 s->bits_sent += (ulg)length; 195 196 /* If not enough room in bi_buf, use (valid) bits from bi_buf and 197 * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid)) 198 * unused bits in value. 199 */ 200 if (s->bi_valid > (int)Buf_size - length) { 201 s->bi_buf |= (ush)value << s->bi_valid; 202 put_short(s, s->bi_buf); 203 s->bi_buf = (ush)value >> (Buf_size - s->bi_valid); 204 s->bi_valid += length - Buf_size; 205 } else { 206 s->bi_buf |= (ush)value << s->bi_valid; 207 s->bi_valid += length; 208 } 209 } 210 #else /* !H2_ZLIB_DEBUG */ 211 212 #define send_bits(s, value, length) \ 213 { int len = length;\ 214 if (s->bi_valid > (int)Buf_size - len) {\ 215 int val = value;\ 216 s->bi_buf |= (ush)val << s->bi_valid;\ 217 put_short(s, s->bi_buf);\ 218 s->bi_buf = (ush)val >> (Buf_size - s->bi_valid);\ 219 s->bi_valid += len - Buf_size;\ 220 } else {\ 221 s->bi_buf |= (ush)(value) << s->bi_valid;\ 222 s->bi_valid += len;\ 223 }\ 224 } 225 #endif /* H2_ZLIB_DEBUG */ 226 227 228 /* the arguments must not have side effects */ 229 230 /* =========================================================================== 231 * Initialize the various 'constant' tables. 232 */ 233 local 234 void 235 tr_static_init(void) 236 { 237 #if defined(GEN_TREES_H) || !defined(STDC) 238 static int static_init_done = 0; 239 int n; /* iterates over tree elements */ 240 int bits; /* bit counter */ 241 int length; /* length value */ 242 int code; /* code value */ 243 int dist; /* distance index */ 244 ush bl_count[MAX_BITS+1]; 245 /* number of codes at each bit length for an optimal tree */ 246 247 if (static_init_done) return; 248 249 /* For some embedded targets, global variables are not initialized: */ 250 #ifdef NO_INIT_GLOBAL_POINTERS 251 static_l_desc.static_tree = static_ltree; 252 static_l_desc.extra_bits = extra_lbits; 253 static_d_desc.static_tree = static_dtree; 254 static_d_desc.extra_bits = extra_dbits; 255 static_bl_desc.extra_bits = extra_blbits; 256 #endif 257 258 /* Initialize the mapping length (0..255) -> length code (0..28) */ 259 length = 0; 260 for (code = 0; code < LENGTH_CODES-1; code++) { 261 base_length[code] = length; 262 for (n = 0; n < (1<<extra_lbits[code]); n++) { 263 _length_code[length++] = (uch)code; 264 } 265 } 266 Assert (length == 256, "tr_static_init: length != 256"); 267 /* Note that the length 255 (match length 258) can be represented 268 * in two different ways: code 284 + 5 bits or code 285, so we 269 * overwrite length_code[255] to use the best encoding: 270 */ 271 _length_code[length-1] = (uch)code; 272 273 /* Initialize the mapping dist (0..32K) -> dist code (0..29) */ 274 dist = 0; 275 for (code = 0 ; code < 16; code++) { 276 base_dist[code] = dist; 277 for (n = 0; n < (1<<extra_dbits[code]); n++) { 278 _dist_code[dist++] = (uch)code; 279 } 280 } 281 Assert (dist == 256, "tr_static_init: dist != 256"); 282 dist >>= 7; /* from now on, all distances are divided by 128 */ 283 for ( ; code < D_CODES; code++) { 284 base_dist[code] = dist << 7; 285 for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) { 286 _dist_code[256 + dist++] = (uch)code; 287 } 288 } 289 Assert (dist == 256, "tr_static_init: 256+dist != 512"); 290 291 /* Construct the codes of the static literal tree */ 292 for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0; 293 n = 0; 294 while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++; 295 while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++; 296 while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++; 297 while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++; 298 /* Codes 286 and 287 do not exist, but we must include them in the 299 * tree construction to get a canonical Huffman tree (longest code 300 * all ones) 301 */ 302 gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count); 303 304 /* The static distance tree is trivial: */ 305 for (n = 0; n < D_CODES; n++) { 306 static_dtree[n].Len = 5; 307 static_dtree[n].Code = bi_reverse((unsigned)n, 5); 308 } 309 static_init_done = 1; 310 311 # ifdef GEN_TREES_H 312 gen_trees_header(); 313 # endif 314 #endif /* defined(GEN_TREES_H) || !defined(STDC) */ 315 } 316 317 /* =========================================================================== 318 * Genererate the file trees.h describing the static trees. 319 */ 320 #ifdef GEN_TREES_H 321 # ifndef H2_ZLIB_DEBUG 322 # include <stdio.h> 323 # endif 324 325 # define SEPARATOR(i, last, width) \ 326 ((i) == (last)? "\n};\n\n" : \ 327 ((i) % (width) == (width)-1 ? ",\n" : ", ")) 328 329 void 330 gen_trees_header() 331 { 332 FILE *header = fopen("trees.h", "w"); 333 int i; 334 335 Assert (header != NULL, "Can't open trees.h"); 336 fprintf(header, 337 "/* header created automatically with -DGEN_TREES_H */\n\n"); 338 339 fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n"); 340 for (i = 0; i < L_CODES+2; i++) { 341 fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code, 342 static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5)); 343 } 344 345 fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n"); 346 for (i = 0; i < D_CODES; i++) { 347 fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code, 348 static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5)); 349 } 350 351 fprintf(header, "const uch ZLIB_INTERNAL _dist_code[DIST_CODE_LEN] = {\n"); 352 for (i = 0; i < DIST_CODE_LEN; i++) { 353 fprintf(header, "%2u%s", _dist_code[i], 354 SEPARATOR(i, DIST_CODE_LEN-1, 20)); 355 } 356 357 fprintf(header, 358 "const uch ZLIB_INTERNAL _length_code[MAX_MATCH-MIN_MATCH+1]= {\n"); 359 for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) { 360 fprintf(header, "%2u%s", _length_code[i], 361 SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20)); 362 } 363 364 fprintf(header, "local const int base_length[LENGTH_CODES] = {\n"); 365 for (i = 0; i < LENGTH_CODES; i++) { 366 fprintf(header, "%1u%s", base_length[i], 367 SEPARATOR(i, LENGTH_CODES-1, 20)); 368 } 369 370 fprintf(header, "local const int base_dist[D_CODES] = {\n"); 371 for (i = 0; i < D_CODES; i++) { 372 fprintf(header, "%5u%s", base_dist[i], 373 SEPARATOR(i, D_CODES-1, 10)); 374 } 375 376 fclose(header); 377 } 378 #endif /* GEN_TREES_H */ 379 380 /* =========================================================================== 381 * Initialize the tree data structures for a new zlib stream. 382 */ 383 void 384 ZLIB_INTERNAL 385 _tr_init(deflate_state *s) 386 { 387 tr_static_init(); 388 389 s->l_desc.dyn_tree = s->dyn_ltree; 390 s->l_desc.stat_desc = &static_l_desc; 391 392 s->d_desc.dyn_tree = s->dyn_dtree; 393 s->d_desc.stat_desc = &static_d_desc; 394 395 s->bl_desc.dyn_tree = s->bl_tree; 396 s->bl_desc.stat_desc = &static_bl_desc; 397 398 s->bi_buf = 0; 399 s->bi_valid = 0; 400 #ifdef H2_ZLIB_DEBUG 401 s->compressed_len = 0L; 402 s->bits_sent = 0L; 403 #endif 404 405 /* Initialize the first block of the first file: */ 406 init_block(s); 407 } 408 409 /* =========================================================================== 410 * Initialize a new block. 411 */ 412 local 413 void 414 init_block(deflate_state *s) 415 { 416 int n; /* iterates over tree elements */ 417 418 /* Initialize the trees. */ 419 for (n = 0; n < L_CODES; n++) s->dyn_ltree[n].Freq = 0; 420 for (n = 0; n < D_CODES; n++) s->dyn_dtree[n].Freq = 0; 421 for (n = 0; n < BL_CODES; n++) s->bl_tree[n].Freq = 0; 422 423 s->dyn_ltree[END_BLOCK].Freq = 1; 424 s->opt_len = s->static_len = 0L; 425 s->last_lit = s->matches = 0; 426 } 427 428 #define SMALLEST 1 429 /* Index within the heap array of least frequent node in the Huffman tree */ 430 431 432 /* =========================================================================== 433 * Remove the smallest element from the heap and recreate the heap with 434 * one less element. Updates heap and heap_len. 435 */ 436 #define pqremove(s, tree, top) \ 437 {\ 438 top = s->heap[SMALLEST]; \ 439 s->heap[SMALLEST] = s->heap[s->heap_len--]; \ 440 pqdownheap(s, tree, SMALLEST); \ 441 } 442 443 /* =========================================================================== 444 * Compares to subtrees, using the tree depth as tie breaker when 445 * the subtrees have equal frequency. This minimizes the worst case length. 446 */ 447 #define smaller(tree, n, m, depth) \ 448 (tree[n].Freq < tree[m].Freq || \ 449 (tree[n].Freq == tree[m].Freq && depth[n] <= depth[m])) 450 451 /* =========================================================================== 452 * Restore the heap property by moving down the tree starting at node k, 453 * exchanging a node with the smallest of its two sons if necessary, stopping 454 * when the heap property is re-established (each father smaller than its 455 * two sons). 456 */ 457 local 458 void 459 pqdownheap(deflate_state *s, ct_data *tree, int k) /* the tree to restore, node to move down */ 460 { 461 int v = s->heap[k]; 462 int j = k << 1; /* left son of k */ 463 while (j <= s->heap_len) { 464 /* Set j to the smallest of the two sons: */ 465 if (j < s->heap_len && 466 smaller(tree, s->heap[j+1], s->heap[j], s->depth)) { 467 j++; 468 } 469 /* Exit if v is smaller than both sons */ 470 if (smaller(tree, v, s->heap[j], s->depth)) break; 471 472 /* Exchange v with the smallest son */ 473 s->heap[k] = s->heap[j]; k = j; 474 475 /* And continue down the tree, setting j to the left son of k */ 476 j <<= 1; 477 } 478 s->heap[k] = v; 479 } 480 481 /* =========================================================================== 482 * Compute the optimal bit lengths for a tree and update the total bit length 483 * for the current block. 484 * IN assertion: the fields freq and dad are set, heap[heap_max] and 485 * above are the tree nodes sorted by increasing frequency. 486 * OUT assertions: the field len is set to the optimal bit length, the 487 * array bl_count contains the frequencies for each bit length. 488 * The length opt_len is updated; static_len is also updated if stree is 489 * not null. 490 */ 491 local 492 void 493 gen_bitlen(deflate_state *s, tree_desc *desc) 494 { 495 ct_data *tree = desc->dyn_tree; 496 int max_code = desc->max_code; 497 const ct_data *stree = desc->stat_desc->static_tree; 498 const intf *extra = desc->stat_desc->extra_bits; 499 int base = desc->stat_desc->extra_base; 500 int max_length = desc->stat_desc->max_length; 501 int h; /* heap index */ 502 int n, m; /* iterate over the tree elements */ 503 int bits; /* bit length */ 504 int xbits; /* extra bits */ 505 ush f; /* frequency */ 506 int overflow = 0; /* number of elements with bit length too large */ 507 508 for (bits = 0; bits <= MAX_BITS; bits++) s->bl_count[bits] = 0; 509 510 /* In a first pass, compute the optimal bit lengths (which may 511 * overflow in the case of the bit length tree). 512 */ 513 tree[s->heap[s->heap_max]].Len = 0; /* root of the heap */ 514 515 for (h = s->heap_max+1; h < HEAP_SIZE; h++) { 516 n = s->heap[h]; 517 bits = tree[tree[n].Dad].Len + 1; 518 if (bits > max_length) bits = max_length, overflow++; 519 tree[n].Len = (ush)bits; 520 /* We overwrite tree[n].Dad which is no longer needed */ 521 522 if (n > max_code) continue; /* not a leaf node */ 523 524 s->bl_count[bits]++; 525 xbits = 0; 526 if (n >= base) xbits = extra[n-base]; 527 f = tree[n].Freq; 528 s->opt_len += (ulg)f * (bits + xbits); 529 if (stree) s->static_len += (ulg)f * (stree[n].Len + xbits); 530 } 531 if (overflow == 0) return; 532 533 Trace((stderr,"\nbit length overflow\n")); 534 /* This happens for example on obj2 and pic of the Calgary corpus */ 535 536 /* Find the first bit length which could increase: */ 537 do { 538 bits = max_length-1; 539 while (s->bl_count[bits] == 0) bits--; 540 s->bl_count[bits]--; /* move one leaf down the tree */ 541 s->bl_count[bits+1] += 2; /* move one overflow item as its brother */ 542 s->bl_count[max_length]--; 543 /* The brother of the overflow item also moves one step up, 544 * but this does not affect bl_count[max_length] 545 */ 546 overflow -= 2; 547 } while (overflow > 0); 548 549 /* Now recompute all bit lengths, scanning in increasing frequency. 550 * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all 551 * lengths instead of fixing only the wrong ones. This idea is taken 552 * from 'ar' written by Haruhiko Okumura.) 553 */ 554 for (bits = max_length; bits != 0; bits--) { 555 n = s->bl_count[bits]; 556 while (n != 0) { 557 m = s->heap[--h]; 558 if (m > max_code) continue; 559 if ((unsigned) tree[m].Len != (unsigned) bits) { 560 Trace((stderr,"code %d bits %d->%d\n", m, tree[m].Len, bits)); 561 s->opt_len += ((long)bits - (long)tree[m].Len) 562 *(long)tree[m].Freq; 563 tree[m].Len = (ush)bits; 564 } 565 n--; 566 } 567 } 568 } 569 570 /* =========================================================================== 571 * Generate the codes for a given tree and bit counts (which need not be 572 * optimal). 573 * IN assertion: the array bl_count contains the bit length statistics for 574 * the given tree and the field len is set for all tree elements. 575 * OUT assertion: the field code is set for all tree elements of non 576 * zero code length. 577 */ 578 local 579 void 580 gen_codes (ct_data *tree, int max_code, ushf *bl_count) 581 /* the tree to decorate */ 582 /* max_code = largest code with non zero frequency */ 583 /* *bl_count = number of codes at each bit length */ 584 { 585 ush next_code[MAX_BITS+1]; /* next code value for each bit length */ 586 ush code = 0; /* running code value */ 587 int bits; /* bit index */ 588 int n; /* code index */ 589 590 /* The distribution counts are first used to generate the code values 591 * without bit reversal. 592 */ 593 for (bits = 1; bits <= MAX_BITS; bits++) { 594 next_code[bits] = code = (code + bl_count[bits-1]) << 1; 595 } 596 /* Check that the bit counts in bl_count are consistent. The last code 597 * must be all ones. 598 */ 599 Assert (code + bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1, 600 "inconsistent bit counts"); 601 Tracev((stderr,"\ngen_codes: max_code %d ", max_code)); 602 603 for (n = 0; n <= max_code; n++) { 604 int len = tree[n].Len; 605 if (len == 0) continue; 606 /* Now reverse the bits */ 607 tree[n].Code = bi_reverse(next_code[len]++, len); 608 609 Tracecv(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ", 610 n, (isgraph(n) ? n : ' '), len, tree[n].Code, next_code[len]-1)); 611 } 612 } 613 614 /* =========================================================================== 615 * Construct one Huffman tree and assigns the code bit strings and lengths. 616 * Update the total bit length for the current block. 617 * IN assertion: the field freq is set for all tree elements. 618 * OUT assertions: the fields len and code are set to the optimal bit length 619 * and corresponding code. The length opt_len is updated; static_len is 620 * also updated if stree is not null. The field max_code is set. 621 */ 622 local 623 void 624 build_tree(deflate_state *s, tree_desc *desc) /* the tree descriptor */ 625 { 626 ct_data *tree = desc->dyn_tree; 627 const ct_data *stree = desc->stat_desc->static_tree; 628 int elems = desc->stat_desc->elems; 629 int n, m; /* iterate over heap elements */ 630 int max_code = -1; /* largest code with non zero frequency */ 631 int node; /* new node being created */ 632 633 /* Construct the initial heap, with least frequent element in 634 * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1]. 635 * heap[0] is not used. 636 */ 637 s->heap_len = 0, s->heap_max = HEAP_SIZE; 638 639 for (n = 0; n < elems; n++) { 640 if (tree[n].Freq != 0) { 641 s->heap[++(s->heap_len)] = max_code = n; 642 s->depth[n] = 0; 643 } else { 644 tree[n].Len = 0; 645 } 646 } 647 648 /* The pkzip format requires that at least one distance code exists, 649 * and that at least one bit should be sent even if there is only one 650 * possible code. So to avoid special checks later on we force at least 651 * two codes of non zero frequency. 652 */ 653 while (s->heap_len < 2) { 654 node = s->heap[++(s->heap_len)] = (max_code < 2 ? ++max_code : 0); 655 tree[node].Freq = 1; 656 s->depth[node] = 0; 657 s->opt_len--; if (stree) s->static_len -= stree[node].Len; 658 /* node is 0 or 1 so it does not have extra bits */ 659 } 660 desc->max_code = max_code; 661 662 /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree, 663 * establish sub-heaps of increasing lengths: 664 */ 665 for (n = s->heap_len/2; n >= 1; n--) pqdownheap(s, tree, n); 666 667 /* Construct the Huffman tree by repeatedly combining the least two 668 * frequent nodes. 669 */ 670 node = elems; /* next internal node of the tree */ 671 do { 672 pqremove(s, tree, n); /* n = node of least frequency */ 673 m = s->heap[SMALLEST]; /* m = node of next least frequency */ 674 675 s->heap[--(s->heap_max)] = n; /* keep the nodes sorted by frequency */ 676 s->heap[--(s->heap_max)] = m; 677 678 /* Create a new node father of n and m */ 679 tree[node].Freq = tree[n].Freq + tree[m].Freq; 680 s->depth[node] = (uch)((s->depth[n] >= s->depth[m] ? 681 s->depth[n] : s->depth[m]) + 1); 682 tree[n].Dad = tree[m].Dad = (ush)node; 683 #ifdef DUMP_BL_TREE 684 if (tree == s->bl_tree) { 685 fprintf(stderr,"\nnode %d(%d), sons %d(%d) %d(%d)", 686 node, tree[node].Freq, n, tree[n].Freq, m, tree[m].Freq); 687 } 688 #endif 689 /* and insert the new node in the heap */ 690 s->heap[SMALLEST] = node++; 691 pqdownheap(s, tree, SMALLEST); 692 693 } while (s->heap_len >= 2); 694 695 s->heap[--(s->heap_max)] = s->heap[SMALLEST]; 696 697 /* At this point, the fields freq and dad are set. We can now 698 * generate the bit lengths. 699 */ 700 gen_bitlen(s, (tree_desc *)desc); 701 702 /* The field len is now set, we can generate the bit codes */ 703 gen_codes ((ct_data *)tree, max_code, s->bl_count); 704 } 705 706 /* =========================================================================== 707 * Scan a literal or distance tree to determine the frequencies of the codes 708 * in the bit length tree. 709 */ 710 local 711 void 712 scan_tree (deflate_state *s, ct_data *tree, int max_code) 713 /* the tree to be scanned */ 714 /* and its largest code of non zero frequency */ 715 { 716 int n; /* iterates over all tree elements */ 717 int prevlen = -1; /* last emitted length */ 718 int curlen; /* length of current code */ 719 int nextlen = tree[0].Len; /* length of next code */ 720 int count = 0; /* repeat count of the current code */ 721 int max_count = 7; /* max repeat count */ 722 int min_count = 4; /* min repeat count */ 723 724 if (nextlen == 0) max_count = 138, min_count = 3; 725 tree[max_code+1].Len = (ush)0xffff; /* guard */ 726 727 for (n = 0; n <= max_code; n++) { 728 curlen = nextlen; nextlen = tree[n+1].Len; 729 if (++count < max_count && curlen == nextlen) { 730 continue; 731 } else if (count < min_count) { 732 s->bl_tree[curlen].Freq += count; 733 } else if (curlen != 0) { 734 if (curlen != prevlen) s->bl_tree[curlen].Freq++; 735 s->bl_tree[REP_3_6].Freq++; 736 } else if (count <= 10) { 737 s->bl_tree[REPZ_3_10].Freq++; 738 } else { 739 s->bl_tree[REPZ_11_138].Freq++; 740 } 741 count = 0; prevlen = curlen; 742 if (nextlen == 0) { 743 max_count = 138, min_count = 3; 744 } else if (curlen == nextlen) { 745 max_count = 6, min_count = 3; 746 } else { 747 max_count = 7, min_count = 4; 748 } 749 } 750 } 751 752 /* =========================================================================== 753 * Send a literal or distance tree in compressed form, using the codes in 754 * bl_tree. 755 */ 756 local 757 void 758 send_tree (deflate_state *s, ct_data *tree, int max_code) /* same as above */ 759 { 760 int n; /* iterates over all tree elements */ 761 int prevlen = -1; /* last emitted length */ 762 int curlen; /* length of current code */ 763 int nextlen = tree[0].Len; /* length of next code */ 764 int count = 0; /* repeat count of the current code */ 765 int max_count = 7; /* max repeat count */ 766 int min_count = 4; /* min repeat count */ 767 768 /* tree[max_code+1].Len = -1; */ /* guard already set */ 769 if (nextlen == 0) max_count = 138, min_count = 3; 770 771 for (n = 0; n <= max_code; n++) { 772 curlen = nextlen; nextlen = tree[n+1].Len; 773 if (++count < max_count && curlen == nextlen) { 774 continue; 775 } else if (count < min_count) { 776 do { send_code(s, curlen, s->bl_tree); } while (--count != 0); 777 778 } else if (curlen != 0) { 779 if (curlen != prevlen) { 780 send_code(s, curlen, s->bl_tree); count--; 781 } 782 Assert(count >= 3 && count <= 6, " 3_6?"); 783 send_code(s, REP_3_6, s->bl_tree); send_bits(s, count-3, 2); 784 785 } else if (count <= 10) { 786 send_code(s, REPZ_3_10, s->bl_tree); send_bits(s, count-3, 3); 787 788 } else { 789 send_code(s, REPZ_11_138, s->bl_tree); send_bits(s, count-11, 7); 790 } 791 count = 0; prevlen = curlen; 792 if (nextlen == 0) { 793 max_count = 138, min_count = 3; 794 } else if (curlen == nextlen) { 795 max_count = 6, min_count = 3; 796 } else { 797 max_count = 7, min_count = 4; 798 } 799 } 800 } 801 802 /* =========================================================================== 803 * Construct the Huffman tree for the bit lengths and return the index in 804 * bl_order of the last bit length code to send. 805 */ 806 local 807 int 808 build_bl_tree(deflate_state *s) 809 { 810 int max_blindex; /* index of last bit length code of non zero freq */ 811 812 /* Determine the bit length frequencies for literal and distance trees */ 813 scan_tree(s, (ct_data *)s->dyn_ltree, s->l_desc.max_code); 814 scan_tree(s, (ct_data *)s->dyn_dtree, s->d_desc.max_code); 815 816 /* Build the bit length tree: */ 817 build_tree(s, (tree_desc *)(&(s->bl_desc))); 818 /* opt_len now includes the length of the tree representations, except 819 * the lengths of the bit lengths codes and the 5+5+4 bits for the counts. 820 */ 821 822 /* Determine the number of bit length codes to send. The pkzip format 823 * requires that at least 4 bit length codes be sent. (appnote.txt says 824 * 3 but the actual value used is 4.) 825 */ 826 for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) { 827 if (s->bl_tree[bl_order[max_blindex]].Len != 0) break; 828 } 829 /* Update opt_len to include the bit length tree and counts */ 830 s->opt_len += 3*(max_blindex+1) + 5+5+4; 831 Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld", 832 s->opt_len, s->static_len)); 833 834 return max_blindex; 835 } 836 837 /* =========================================================================== 838 * Send the header for a block using dynamic Huffman trees: the counts, the 839 * lengths of the bit length codes, the literal tree and the distance tree. 840 * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4. 841 */ 842 local 843 void 844 send_all_trees(deflate_state *s, int lcodes, int dcodes, int blcodes) 845 /* number of codes for each tree */ 846 { 847 int rank; /* index in bl_order */ 848 849 Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes"); 850 Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES, 851 "too many codes"); 852 Tracev((stderr, "\nbl counts: ")); 853 send_bits(s, lcodes-257, 5); /* not +255 as stated in appnote.txt */ 854 send_bits(s, dcodes-1, 5); 855 send_bits(s, blcodes-4, 4); /* not -3 as stated in appnote.txt */ 856 for (rank = 0; rank < blcodes; rank++) { 857 Tracev((stderr, "\nbl code %2d ", bl_order[rank])); 858 send_bits(s, s->bl_tree[bl_order[rank]].Len, 3); 859 } 860 Tracev((stderr, "\nbl tree: sent %ld", s->bits_sent)); 861 862 send_tree(s, (ct_data *)s->dyn_ltree, lcodes-1); /* literal tree */ 863 Tracev((stderr, "\nlit tree: sent %ld", s->bits_sent)); 864 865 send_tree(s, (ct_data *)s->dyn_dtree, dcodes-1); /* distance tree */ 866 Tracev((stderr, "\ndist tree: sent %ld", s->bits_sent)); 867 } 868 869 /* =========================================================================== 870 * Send a stored block 871 */ 872 void 873 ZLIB_INTERNAL 874 _tr_stored_block(deflate_state *s, charf *buf, 875 ulg stored_len, int last) /* one if this is the last block for a file */ 876 { 877 send_bits(s, (STORED_BLOCK<<1)+last, 3); /* send block type */ 878 #ifdef H2_ZLIB_DEBUG 879 s->compressed_len = (s->compressed_len + 3 + 7) & (ulg)~7L; 880 s->compressed_len += (stored_len + 4) << 3; 881 #endif 882 copy_block(s, buf, (unsigned)stored_len, 1); /* with header */ 883 } 884 885 /* =========================================================================== 886 * Flush the bits in the bit buffer to pending output (leaves at most 7 bits) 887 */ 888 void 889 ZLIB_INTERNAL 890 _tr_flush_bits(deflate_state *s) 891 { 892 bi_flush(s); 893 } 894 895 /* =========================================================================== 896 * Send one empty static block to give enough lookahead for inflate. 897 * This takes 10 bits, of which 7 may remain in the bit buffer. 898 */ 899 void 900 ZLIB_INTERNAL 901 _tr_align(deflate_state *s) 902 { 903 send_bits(s, STATIC_TREES<<1, 3); 904 send_code(s, END_BLOCK, static_ltree); 905 #ifdef H2_ZLIB_DEBUG 906 s->compressed_len += 10L; /* 3 for block type, 7 for EOB */ 907 #endif 908 bi_flush(s); 909 } 910 911 /* =========================================================================== 912 * Determine the best encoding for the current block: dynamic trees, static 913 * trees or store, and output the encoded block to the zip file. 914 */ 915 void 916 ZLIB_INTERNAL 917 _tr_flush_block(deflate_state *s, charf *buf, 918 ulg stored_len, int last) 919 { 920 ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */ 921 int max_blindex = 0; /* index of last bit length code of non zero freq */ 922 923 /* Build the Huffman trees unless a stored block is forced */ 924 if (s->level > 0) { 925 926 /* Check if the file is binary or text */ 927 if (s->strm->data_type == Z_UNKNOWN) 928 s->strm->data_type = detect_data_type(s); 929 930 /* Construct the literal and distance trees */ 931 build_tree(s, (tree_desc *)(&(s->l_desc))); 932 Tracev((stderr, "\nlit data: dyn %ld, stat %ld", s->opt_len, 933 s->static_len)); 934 935 build_tree(s, (tree_desc *)(&(s->d_desc))); 936 Tracev((stderr, "\ndist data: dyn %ld, stat %ld", s->opt_len, 937 s->static_len)); 938 /* At this point, opt_len and static_len are the total bit lengths of 939 * the compressed block data, excluding the tree representations. 940 */ 941 942 /* Build the bit length tree for the above two trees, and get the index 943 * in bl_order of the last bit length code to send. 944 */ 945 max_blindex = build_bl_tree(s); 946 947 /* Determine the best encoding. Compute the block lengths in bytes. */ 948 opt_lenb = (s->opt_len+3+7)>>3; 949 static_lenb = (s->static_len+3+7)>>3; 950 951 Tracev((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u ", 952 opt_lenb, s->opt_len, static_lenb, s->static_len, stored_len, 953 s->last_lit)); 954 955 if (static_lenb <= opt_lenb) opt_lenb = static_lenb; 956 957 } else { 958 Assert(buf != (char*)0, "lost buf"); 959 opt_lenb = static_lenb = stored_len + 5; /* force a stored block */ 960 } 961 962 #ifdef FORCE_STORED 963 if (buf != (char*)0) { /* force stored block */ 964 #else 965 if (stored_len+4 <= opt_lenb && buf != (char*)0) { 966 /* 4: two words for the lengths */ 967 #endif 968 /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE. 969 * Otherwise we can't have processed more than WSIZE input bytes since 970 * the last block flush, because compression would have been 971 * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to 972 * transform a block into a stored block. 973 */ 974 _tr_stored_block(s, buf, stored_len, last); 975 976 #ifdef FORCE_STATIC 977 } else if (static_lenb >= 0) { /* force static trees */ 978 #else 979 } else if (s->strategy == Z_FIXED || static_lenb == opt_lenb) { 980 #endif 981 send_bits(s, (STATIC_TREES<<1)+last, 3); 982 compress_block(s, (const ct_data *)static_ltree, 983 (const ct_data *)static_dtree); 984 #ifdef H2_ZLIB_DEBUG 985 s->compressed_len += 3 + s->static_len; 986 #endif 987 } else { 988 send_bits(s, (DYN_TREES<<1)+last, 3); 989 send_all_trees(s, s->l_desc.max_code+1, s->d_desc.max_code+1, 990 max_blindex+1); 991 compress_block(s, (const ct_data *)s->dyn_ltree, 992 (const ct_data *)s->dyn_dtree); 993 #ifdef H2_ZLIB_DEBUG 994 s->compressed_len += 3 + s->opt_len; 995 #endif 996 } 997 Assert (s->compressed_len == s->bits_sent, "bad compressed size"); 998 /* The above check is made mod 2^32, for files larger than 512 MB 999 * and uLong implemented on 32 bits. 1000 */ 1001 init_block(s); 1002 1003 if (last) { 1004 bi_windup(s); 1005 #ifdef H2_ZLIB_DEBUG 1006 s->compressed_len += 7; /* align on byte boundary */ 1007 #endif 1008 } 1009 Tracev((stderr,"\ncomprlen %lu(%lu) ", s->compressed_len>>3, 1010 s->compressed_len-7*last)); 1011 } 1012 1013 /* =========================================================================== 1014 * Save the match info and tally the frequency counts. Return true if 1015 * the current block must be flushed. 1016 */ 1017 int 1018 ZLIB_INTERNAL 1019 _tr_tally (deflate_state *s, unsigned dist, unsigned lc) 1020 { 1021 s->d_buf[s->last_lit] = (ush)dist; 1022 s->l_buf[s->last_lit++] = (uch)lc; 1023 if (dist == 0) { 1024 /* lc is the unmatched char */ 1025 s->dyn_ltree[lc].Freq++; 1026 } else { 1027 s->matches++; 1028 /* Here, lc is the match length - MIN_MATCH */ 1029 dist--; /* dist = match distance - 1 */ 1030 Assert((ush)dist < (ush)MAX_DIST(s) && 1031 (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) && 1032 (ush)d_code(dist) < (ush)D_CODES, "_tr_tally: bad match"); 1033 1034 s->dyn_ltree[_length_code[lc]+LITERALS+1].Freq++; 1035 s->dyn_dtree[d_code(dist)].Freq++; 1036 } 1037 1038 #ifdef TRUNCATE_BLOCK 1039 /* Try to guess if it is profitable to stop the current block here */ 1040 if ((s->last_lit & 0x1fff) == 0 && s->level > 2) { 1041 /* Compute an upper bound for the compressed length */ 1042 ulg out_length = (ulg)s->last_lit*8L; 1043 ulg in_length = (ulg)((long)s->strstart - s->block_start); 1044 int dcode; 1045 for (dcode = 0; dcode < D_CODES; dcode++) { 1046 out_length += (ulg)s->dyn_dtree[dcode].Freq * 1047 (5L+extra_dbits[dcode]); 1048 } 1049 out_length >>= 3; 1050 Tracev((stderr,"\nlast_lit %u, in %ld, out ~%ld(%ld%%) ", 1051 s->last_lit, in_length, out_length, 1052 100L - out_length*100L/in_length)); 1053 if (s->matches < s->last_lit/2 && out_length < in_length/2) return 1; 1054 } 1055 #endif 1056 return (s->last_lit == s->lit_bufsize-1); 1057 /* We avoid equality with lit_bufsize because of wraparound at 64K 1058 * on 16 bit machines and because stored blocks are restricted to 1059 * 64K-1 bytes. 1060 */ 1061 } 1062 1063 /* =========================================================================== 1064 * Send the block data compressed using the given Huffman trees 1065 */ 1066 local 1067 void 1068 compress_block(deflate_state *s, const ct_data *ltree, const ct_data *dtree) 1069 { 1070 unsigned dist; /* distance of matched string */ 1071 int lc; /* match length or unmatched char (if dist == 0) */ 1072 unsigned lx = 0; /* running index in l_buf */ 1073 unsigned code; /* the code to send */ 1074 int extra; /* number of extra bits to send */ 1075 1076 if (s->last_lit != 0) do { 1077 dist = s->d_buf[lx]; 1078 lc = s->l_buf[lx++]; 1079 if (dist == 0) { 1080 send_code(s, lc, ltree); /* send a literal byte */ 1081 Tracecv(isgraph(lc), (stderr," '%c' ", lc)); 1082 } else { 1083 /* Here, lc is the match length - MIN_MATCH */ 1084 code = _length_code[lc]; 1085 send_code(s, code+LITERALS+1, ltree); /* send the length code */ 1086 extra = extra_lbits[code]; 1087 if (extra != 0) { 1088 lc -= base_length[code]; 1089 send_bits(s, lc, extra); /* send the extra length bits */ 1090 } 1091 dist--; /* dist is now the match distance - 1 */ 1092 code = d_code(dist); 1093 Assert (code < D_CODES, "bad d_code"); 1094 1095 send_code(s, code, dtree); /* send the distance code */ 1096 extra = extra_dbits[code]; 1097 if (extra != 0) { 1098 dist -= base_dist[code]; 1099 send_bits(s, dist, extra); /* send the extra distance bits */ 1100 } 1101 } /* literal or match pair ? */ 1102 1103 /* Check that the overlay between pending_buf and d_buf+l_buf is ok: */ 1104 Assert((uInt)(s->pending) < s->lit_bufsize + 2*lx, 1105 "pendingBuf overflow"); 1106 1107 } while (lx < s->last_lit); 1108 1109 send_code(s, END_BLOCK, ltree); 1110 } 1111 1112 /* =========================================================================== 1113 * Check if the data type is TEXT or BINARY, using the following algorithm: 1114 * - TEXT if the two conditions below are satisfied: 1115 * a) There are no non-portable control characters belonging to the 1116 * "black list" (0..6, 14..25, 28..31). 1117 * b) There is at least one printable character belonging to the 1118 * "white list" (9 {TAB}, 10 {LF}, 13 {CR}, 32..255). 1119 * - BINARY otherwise. 1120 * - The following partially-portable control characters form a 1121 * "gray list" that is ignored in this detection algorithm: 1122 * (7 {BEL}, 8 {BS}, 11 {VT}, 12 {FF}, 26 {SUB}, 27 {ESC}). 1123 * IN assertion: the fields Freq of dyn_ltree are set. 1124 */ 1125 local 1126 int 1127 detect_data_type(deflate_state *s) 1128 { 1129 /* black_mask is the bit mask of black-listed bytes 1130 * set bits 0..6, 14..25, and 28..31 1131 * 0xf3ffc07f = binary 11110011111111111100000001111111 1132 */ 1133 unsigned long black_mask = 0xf3ffc07fUL; 1134 int n; 1135 1136 /* Check for non-textual ("black-listed") bytes. */ 1137 for (n = 0; n <= 31; n++, black_mask >>= 1) 1138 if ((black_mask & 1) && (s->dyn_ltree[n].Freq != 0)) 1139 return Z_BINARY; 1140 1141 /* Check for textual ("white-listed") bytes. */ 1142 if (s->dyn_ltree[9].Freq != 0 || s->dyn_ltree[10].Freq != 0 1143 || s->dyn_ltree[13].Freq != 0) 1144 return Z_TEXT; 1145 for (n = 32; n < LITERALS; n++) 1146 if (s->dyn_ltree[n].Freq != 0) 1147 return Z_TEXT; 1148 1149 /* There are no "black-listed" or "white-listed" bytes: 1150 * this stream either is empty or has tolerated ("gray-listed") bytes only. 1151 */ 1152 return Z_BINARY; 1153 } 1154 1155 /* =========================================================================== 1156 * Reverse the first len bits of a code, using straightforward code (a faster 1157 * method would use a table) 1158 * IN assertion: 1 <= len <= 15 1159 */ 1160 local 1161 unsigned 1162 bi_reverse(unsigned code, int len) 1163 { 1164 register unsigned res = 0; 1165 do { 1166 res |= code & 1; 1167 code >>= 1, res <<= 1; 1168 } while (--len > 0); 1169 return res >> 1; 1170 } 1171 1172 /* =========================================================================== 1173 * Flush the bit buffer, keeping at most 7 bits in it. 1174 */ 1175 local 1176 void 1177 bi_flush(deflate_state *s) 1178 { 1179 if (s->bi_valid == 16) { 1180 put_short(s, s->bi_buf); 1181 s->bi_buf = 0; 1182 s->bi_valid = 0; 1183 } else if (s->bi_valid >= 8) { 1184 put_byte(s, (Byte)s->bi_buf); 1185 s->bi_buf >>= 8; 1186 s->bi_valid -= 8; 1187 } 1188 } 1189 1190 /* =========================================================================== 1191 * Flush the bit buffer and align the output on a byte boundary 1192 */ 1193 local 1194 void 1195 bi_windup(deflate_state *s) 1196 { 1197 if (s->bi_valid > 8) { 1198 put_short(s, s->bi_buf); 1199 } else if (s->bi_valid > 0) { 1200 put_byte(s, (Byte)s->bi_buf); 1201 } 1202 s->bi_buf = 0; 1203 s->bi_valid = 0; 1204 #ifdef H2_ZLIB_DEBUG 1205 s->bits_sent = (s->bits_sent+7) & ~7; 1206 #endif 1207 } 1208 1209 /* =========================================================================== 1210 * Copy a stored block, storing first the length and its 1211 * one's complement if requested. 1212 */ 1213 local 1214 void 1215 copy_block(deflate_state *s, charf *buf, unsigned len, int header) 1216 { 1217 bi_windup(s); /* align on byte boundary */ 1218 1219 if (header) { 1220 put_short(s, (ush)len); 1221 put_short(s, (ush)~len); 1222 #ifdef H2_ZLIB_DEBUG 1223 s->bits_sent += 2*16; 1224 #endif 1225 } 1226 #ifdef H2_ZLIB_DEBUG 1227 s->bits_sent += (ulg)len<<3; 1228 #endif 1229 while (len--) { 1230 put_byte(s, *buf++); 1231 } 1232 } 1233