1 /** 2 * xzlib.c: front end for the transparent suport of lzma compression 3 * at the I/O layer, based on an example file from lzma project 4 * 5 * See Copyright for the status of this software. 6 * 7 * Anders F Bjorklund <afb (at) users.sourceforge.net> 8 */ 9 #define IN_LIBXML 10 #include "libxml.h" 11 #ifdef LIBXML_LZMA_ENABLED 12 13 #include <string.h> 14 #ifdef HAVE_ERRNO_H 15 #include <errno.h> 16 #endif 17 18 19 #ifdef HAVE_SYS_TYPES_H 20 #include <sys/types.h> 21 #endif 22 #ifdef HAVE_SYS_STAT_H 23 #include <sys/stat.h> 24 #endif 25 #ifdef HAVE_FCNTL_H 26 #include <fcntl.h> 27 #endif 28 #ifdef HAVE_UNISTD_H 29 #include <unistd.h> 30 #endif 31 #ifdef HAVE_STDLIB_H 32 #include <stdlib.h> 33 #endif 34 #ifdef LIBXML_ZLIB_ENABLED 35 #include <zlib.h> 36 #endif 37 #ifdef LIBXML_LZMA_ENABLED 38 #include <lzma.h> 39 #endif 40 41 #include "xzlib.h" 42 #include <libxml/xmlmemory.h> 43 44 /* values for xz_state how */ 45 #define LOOK 0 /* look for a gzip/lzma header */ 46 #define COPY 1 /* copy input directly */ 47 #define GZIP 2 /* decompress a gzip stream */ 48 #define LZMA 3 /* decompress a lzma stream */ 49 50 /* internal lzma file state data structure */ 51 typedef struct { 52 int mode; /* see lzma modes above */ 53 int fd; /* file descriptor */ 54 char *path; /* path or fd for error messages */ 55 uint64_t pos; /* current position in uncompressed data */ 56 unsigned int size; /* buffer size, zero if not allocated yet */ 57 unsigned int want; /* requested buffer size, default is BUFSIZ */ 58 unsigned char *in; /* input buffer */ 59 unsigned char *out; /* output buffer (double-sized when reading) */ 60 unsigned char *next; /* next output data to deliver or write */ 61 unsigned int have; /* amount of output data unused at next */ 62 int eof; /* true if end of input file reached */ 63 uint64_t start; /* where the lzma data started, for rewinding */ 64 uint64_t raw; /* where the raw data started, for seeking */ 65 int how; /* 0: get header, 1: copy, 2: decompress */ 66 int direct; /* true if last read direct, false if lzma */ 67 /* seek request */ 68 uint64_t skip; /* amount to skip (already rewound if backwards) */ 69 int seek; /* true if seek request pending */ 70 /* error information */ 71 int err; /* error code */ 72 char *msg; /* error message */ 73 /* lzma stream */ 74 int init; /* is the iniflate stream initialized */ 75 lzma_stream strm; /* stream structure in-place (not a pointer) */ 76 char padding1[32]; /* padding allowing to cope with possible 77 extensions of above structure without 78 too much side effect */ 79 #ifdef LIBXML_ZLIB_ENABLED 80 /* zlib inflate or deflate stream */ 81 z_stream zstrm; /* stream structure in-place (not a pointer) */ 82 #endif 83 char padding2[32]; /* padding allowing to cope with possible 84 extensions of above structure without 85 too much side effect */ 86 } xz_state, *xz_statep; 87 88 static void 89 xz_error(xz_statep state, int err, const char *msg) 90 { 91 /* free previously allocated message and clear */ 92 if (state->msg != NULL) { 93 if (state->err != LZMA_MEM_ERROR) 94 xmlFree(state->msg); 95 state->msg = NULL; 96 } 97 98 /* set error code, and if no message, then done */ 99 state->err = err; 100 if (msg == NULL) 101 return; 102 103 /* for an out of memory error, save as static string */ 104 if (err == LZMA_MEM_ERROR) { 105 state->msg = (char *) msg; 106 return; 107 } 108 109 /* construct error message with path */ 110 if ((state->msg = 111 xmlMalloc(strlen(state->path) + strlen(msg) + 3)) == NULL) { 112 state->err = LZMA_MEM_ERROR; 113 state->msg = (char *) "out of memory"; 114 return; 115 } 116 strcpy(state->msg, state->path); 117 strcat(state->msg, ": "); 118 strcat(state->msg, msg); 119 return; 120 } 121 122 static void 123 xz_reset(xz_statep state) 124 { 125 state->have = 0; /* no output data available */ 126 state->eof = 0; /* not at end of file */ 127 state->how = LOOK; /* look for gzip header */ 128 state->direct = 1; /* default for empty file */ 129 state->seek = 0; /* no seek request pending */ 130 xz_error(state, LZMA_OK, NULL); /* clear error */ 131 state->pos = 0; /* no uncompressed data yet */ 132 state->strm.avail_in = 0; /* no input data yet */ 133 #ifdef LIBXML_ZLIB_ENABLED 134 state->zstrm.avail_in = 0; /* no input data yet */ 135 #endif 136 } 137 138 static xzFile 139 xz_open(const char *path, int fd, const char *mode ATTRIBUTE_UNUSED) 140 { 141 xz_statep state; 142 143 /* allocate xzFile structure to return */ 144 state = xmlMalloc(sizeof(xz_state)); 145 if (state == NULL) 146 return NULL; 147 state->size = 0; /* no buffers allocated yet */ 148 state->want = BUFSIZ; /* requested buffer size */ 149 state->msg = NULL; /* no error message yet */ 150 state->init = 0; /* initialization of zlib data */ 151 152 /* save the path name for error messages */ 153 state->path = xmlMalloc(strlen(path) + 1); 154 if (state->path == NULL) { 155 xmlFree(state); 156 return NULL; 157 } 158 strcpy(state->path, path); 159 160 /* open the file with the appropriate mode (or just use fd) */ 161 state->fd = fd != -1 ? fd : open(path, 162 #ifdef O_LARGEFILE 163 O_LARGEFILE | 164 #endif 165 #ifdef O_BINARY 166 O_BINARY | 167 #endif 168 O_RDONLY, 0666); 169 if (state->fd == -1) { 170 xmlFree(state->path); 171 xmlFree(state); 172 return NULL; 173 } 174 175 /* save the current position for rewinding (only if reading) */ 176 state->start = lseek(state->fd, 0, SEEK_CUR); 177 if (state->start == (uint64_t) - 1) 178 state->start = 0; 179 180 /* initialize stream */ 181 xz_reset(state); 182 183 /* return stream */ 184 return (xzFile) state; 185 } 186 187 static int 188 xz_compressed(xzFile f) { 189 xz_statep state; 190 191 if (f == NULL) 192 return(-1); 193 state = (xz_statep) f; 194 if (state->init <= 0) 195 return(-1); 196 197 switch (state->how) { 198 case COPY: 199 return(0); 200 case GZIP: 201 case LZMA: 202 return(1); 203 } 204 return(-1); 205 } 206 207 xzFile 208 __libxml2_xzopen(const char *path, const char *mode) 209 { 210 return xz_open(path, -1, mode); 211 } 212 213 int 214 __libxml2_xzcompressed(xzFile f) { 215 return xz_compressed(f); 216 } 217 218 xzFile 219 __libxml2_xzdopen(int fd, const char *mode) 220 { 221 char *path; /* identifier for error messages */ 222 xzFile xz; 223 224 if (fd == -1 || (path = xmlMalloc(7 + 3 * sizeof(int))) == NULL) 225 return NULL; 226 sprintf(path, "<fd:%d>", fd); /* for debugging */ 227 xz = xz_open(path, fd, mode); 228 xmlFree(path); 229 return xz; 230 } 231 232 static int 233 xz_load(xz_statep state, unsigned char *buf, unsigned int len, 234 unsigned int *have) 235 { 236 int ret; 237 238 *have = 0; 239 do { 240 ret = read(state->fd, buf + *have, len - *have); 241 if (ret <= 0) 242 break; 243 *have += ret; 244 } while (*have < len); 245 if (ret < 0) { 246 xz_error(state, -1, strerror(errno)); 247 return -1; 248 } 249 if (ret == 0) 250 state->eof = 1; 251 return 0; 252 } 253 254 static int 255 xz_avail(xz_statep state) 256 { 257 lzma_stream *strm = &(state->strm); 258 259 if (state->err != LZMA_OK) 260 return -1; 261 if (state->eof == 0) { 262 /* avail_in is size_t, which is not necessary sizeof(unsigned) */ 263 unsigned tmp = strm->avail_in; 264 265 if (xz_load(state, state->in, state->size, &tmp) == -1) { 266 strm->avail_in = tmp; 267 return -1; 268 } 269 strm->avail_in = tmp; 270 strm->next_in = state->in; 271 } 272 return 0; 273 } 274 275 #ifdef LIBXML_ZLIB_ENABLED 276 static int 277 xz_avail_zstrm(xz_statep state) 278 { 279 int ret; 280 state->strm.avail_in = state->zstrm.avail_in; 281 state->strm.next_in = state->zstrm.next_in; 282 ret = xz_avail(state); 283 state->zstrm.avail_in = (uInt) state->strm.avail_in; 284 state->zstrm.next_in = (Bytef *) state->strm.next_in; 285 return ret; 286 } 287 #endif 288 289 static int 290 is_format_xz(xz_statep state) 291 { 292 lzma_stream *strm = &(state->strm); 293 294 return strm->avail_in >= 6 && memcmp(state->in, "\3757zXZ", 6) == 0; 295 } 296 297 static int 298 is_format_lzma(xz_statep state) 299 { 300 lzma_stream *strm = &(state->strm); 301 302 lzma_filter filter; 303 lzma_options_lzma *opt; 304 uint32_t dict_size; 305 uint64_t uncompressed_size; 306 size_t i; 307 308 if (strm->avail_in < 13) 309 return 0; 310 311 filter.id = LZMA_FILTER_LZMA1; 312 if (lzma_properties_decode(&filter, NULL, state->in, 5) != LZMA_OK) 313 return 0; 314 315 opt = filter.options; 316 dict_size = opt->dict_size; 317 free(opt); /* we can't use xmlFree on a string returned by zlib */ 318 319 /* A hack to ditch tons of false positives: We allow only dictionary 320 * sizes that are 2^n or 2^n + 2^(n-1) or UINT32_MAX. LZMA_Alone 321 * created only files with 2^n, but accepts any dictionary size. 322 * If someone complains, this will be reconsidered. 323 */ 324 if (dict_size != UINT32_MAX) { 325 uint32_t d = dict_size - 1; 326 327 d |= d >> 2; 328 d |= d >> 3; 329 d |= d >> 4; 330 d |= d >> 8; 331 d |= d >> 16; 332 ++d; 333 if (d != dict_size || dict_size == 0) 334 return 0; 335 } 336 337 /* Another hack to ditch false positives: Assume that if the 338 * uncompressed size is known, it must be less than 256 GiB. 339 * Again, if someone complains, this will be reconsidered. 340 */ 341 uncompressed_size = 0; 342 for (i = 0; i < 8; ++i) 343 uncompressed_size |= (uint64_t) (state->in[5 + i]) << (i * 8); 344 345 if (uncompressed_size != UINT64_MAX 346 && uncompressed_size > (UINT64_C(1) << 38)) 347 return 0; 348 349 return 1; 350 } 351 352 #ifdef LIBXML_ZLIB_ENABLED 353 354 /* Get next byte from input, or -1 if end or error. */ 355 #define NEXT() ((strm->avail_in == 0 && xz_avail(state) == -1) ? -1 : \ 356 (strm->avail_in == 0 ? -1 : \ 357 (strm->avail_in--, *(strm->next_in)++))) 358 /* Same thing, but from zstrm */ 359 #define NEXTZ() ((strm->avail_in == 0 && xz_avail_zstrm(state) == -1) ? -1 : \ 360 (strm->avail_in == 0 ? -1 : \ 361 (strm->avail_in--, *(strm->next_in)++))) 362 363 /* Get a four-byte little-endian integer and return 0 on success and the value 364 in *ret. Otherwise -1 is returned and *ret is not modified. */ 365 static int 366 gz_next4(xz_statep state, unsigned long *ret) 367 { 368 int ch; 369 unsigned long val; 370 z_streamp strm = &(state->zstrm); 371 372 val = NEXTZ(); 373 val += (unsigned) NEXTZ() << 8; 374 val += (unsigned long) NEXTZ() << 16; 375 ch = NEXTZ(); 376 if (ch == -1) 377 return -1; 378 val += (unsigned long) ch << 24; 379 *ret = val; 380 return 0; 381 } 382 #endif 383 384 static int 385 xz_head(xz_statep state) 386 { 387 lzma_stream *strm = &(state->strm); 388 lzma_stream init = LZMA_STREAM_INIT; 389 int flags; 390 unsigned len; 391 392 /* allocate read buffers and inflate memory */ 393 if (state->size == 0) { 394 /* allocate buffers */ 395 state->in = xmlMalloc(state->want); 396 state->out = xmlMalloc(state->want << 1); 397 if (state->in == NULL || state->out == NULL) { 398 if (state->out != NULL) 399 xmlFree(state->out); 400 if (state->in != NULL) 401 xmlFree(state->in); 402 xz_error(state, LZMA_MEM_ERROR, "out of memory"); 403 return -1; 404 } 405 state->size = state->want; 406 407 /* allocate decoder memory */ 408 state->strm = init; 409 state->strm.avail_in = 0; 410 state->strm.next_in = NULL; 411 if (lzma_auto_decoder(&state->strm, 100000000, 0) != LZMA_OK) { 412 xmlFree(state->out); 413 xmlFree(state->in); 414 state->size = 0; 415 xz_error(state, LZMA_MEM_ERROR, "out of memory"); 416 return -1; 417 } 418 #ifdef LIBXML_ZLIB_ENABLED 419 /* allocate inflate memory */ 420 state->zstrm.zalloc = Z_NULL; 421 state->zstrm.zfree = Z_NULL; 422 state->zstrm.opaque = Z_NULL; 423 state->zstrm.avail_in = 0; 424 state->zstrm.next_in = Z_NULL; 425 if (state->init == 0) { 426 if (inflateInit2(&(state->zstrm), -15) != Z_OK) {/* raw inflate */ 427 xmlFree(state->out); 428 xmlFree(state->in); 429 state->size = 0; 430 xz_error(state, LZMA_MEM_ERROR, "out of memory"); 431 return -1; 432 } 433 state->init = 1; 434 } 435 #endif 436 } 437 438 /* get some data in the input buffer */ 439 if (strm->avail_in == 0) { 440 if (xz_avail(state) == -1) 441 return -1; 442 if (strm->avail_in == 0) 443 return 0; 444 } 445 446 /* look for the xz magic header bytes */ 447 if (is_format_xz(state) || is_format_lzma(state)) { 448 state->how = LZMA; 449 state->direct = 0; 450 return 0; 451 } 452 #ifdef LIBXML_ZLIB_ENABLED 453 /* look for the gzip magic header bytes 31 and 139 */ 454 if (strm->next_in[0] == 31) { 455 strm->avail_in--; 456 strm->next_in++; 457 if (strm->avail_in == 0 && xz_avail(state) == -1) 458 return -1; 459 if (strm->avail_in && strm->next_in[0] == 139) { 460 /* we have a gzip header, woo hoo! */ 461 strm->avail_in--; 462 strm->next_in++; 463 464 /* skip rest of header */ 465 if (NEXT() != 8) { /* compression method */ 466 xz_error(state, LZMA_DATA_ERROR, 467 "unknown compression method"); 468 return -1; 469 } 470 flags = NEXT(); 471 if (flags & 0xe0) { /* reserved flag bits */ 472 xz_error(state, LZMA_DATA_ERROR, 473 "unknown header flags set"); 474 return -1; 475 } 476 NEXT(); /* modification time */ 477 NEXT(); 478 NEXT(); 479 NEXT(); 480 NEXT(); /* extra flags */ 481 NEXT(); /* operating system */ 482 if (flags & 4) { /* extra field */ 483 len = (unsigned) NEXT(); 484 len += (unsigned) NEXT() << 8; 485 while (len--) 486 if (NEXT() < 0) 487 break; 488 } 489 if (flags & 8) /* file name */ 490 while (NEXT() > 0) ; 491 if (flags & 16) /* comment */ 492 while (NEXT() > 0) ; 493 if (flags & 2) { /* header crc */ 494 NEXT(); 495 NEXT(); 496 } 497 /* an unexpected end of file is not checked for here -- it will be 498 * noticed on the first request for uncompressed data */ 499 500 /* set up for decompression */ 501 inflateReset(&state->zstrm); 502 state->zstrm.adler = crc32(0L, Z_NULL, 0); 503 state->how = GZIP; 504 state->direct = 0; 505 return 0; 506 } else { 507 /* not a gzip file -- save first byte (31) and fall to raw i/o */ 508 state->out[0] = 31; 509 state->have = 1; 510 } 511 } 512 #endif 513 514 /* doing raw i/o, save start of raw data for seeking, copy any leftover 515 * input to output -- this assumes that the output buffer is larger than 516 * the input buffer, which also assures space for gzungetc() */ 517 state->raw = state->pos; 518 state->next = state->out; 519 if (strm->avail_in) { 520 memcpy(state->next + state->have, strm->next_in, strm->avail_in); 521 state->have += strm->avail_in; 522 strm->avail_in = 0; 523 } 524 state->how = COPY; 525 state->direct = 1; 526 return 0; 527 } 528 529 static int 530 xz_decomp(xz_statep state) 531 { 532 int ret; 533 unsigned had; 534 unsigned long crc, len; 535 lzma_stream *strm = &(state->strm); 536 537 lzma_action action = LZMA_RUN; 538 539 /* fill output buffer up to end of deflate stream */ 540 had = strm->avail_out; 541 do { 542 /* get more input for inflate() */ 543 if (strm->avail_in == 0 && xz_avail(state) == -1) 544 return -1; 545 if (strm->avail_in == 0) { 546 xz_error(state, LZMA_DATA_ERROR, "unexpected end of file"); 547 return -1; 548 } 549 if (state->eof) 550 action = LZMA_FINISH; 551 552 /* decompress and handle errors */ 553 #ifdef LIBXML_ZLIB_ENABLED 554 if (state->how == GZIP) { 555 state->zstrm.avail_in = (uInt) state->strm.avail_in; 556 state->zstrm.next_in = (Bytef *) state->strm.next_in; 557 state->zstrm.avail_out = (uInt) state->strm.avail_out; 558 state->zstrm.next_out = (Bytef *) state->strm.next_out; 559 ret = inflate(&state->zstrm, Z_NO_FLUSH); 560 if (ret == Z_STREAM_ERROR || ret == Z_NEED_DICT) { 561 xz_error(state, Z_STREAM_ERROR, 562 "internal error: inflate stream corrupt"); 563 return -1; 564 } 565 /* 566 * FIXME: Remapping a couple of error codes and falling through 567 * to the LZMA error handling looks fragile. 568 */ 569 if (ret == Z_MEM_ERROR) 570 ret = LZMA_MEM_ERROR; 571 if (ret == Z_DATA_ERROR) 572 ret = LZMA_DATA_ERROR; 573 if (ret == Z_STREAM_END) 574 ret = LZMA_STREAM_END; 575 state->strm.avail_in = state->zstrm.avail_in; 576 state->strm.next_in = state->zstrm.next_in; 577 state->strm.avail_out = state->zstrm.avail_out; 578 state->strm.next_out = state->zstrm.next_out; 579 } else /* state->how == LZMA */ 580 #endif 581 ret = lzma_code(strm, action); 582 if (ret == LZMA_MEM_ERROR) { 583 xz_error(state, LZMA_MEM_ERROR, "out of memory"); 584 return -1; 585 } 586 if (ret == LZMA_DATA_ERROR) { 587 xz_error(state, LZMA_DATA_ERROR, "compressed data error"); 588 return -1; 589 } 590 if (ret == LZMA_PROG_ERROR) { 591 xz_error(state, LZMA_PROG_ERROR, "compression error"); 592 return -1; 593 } 594 if ((state->how != GZIP) && 595 (ret != LZMA_OK) && (ret != LZMA_STREAM_END)) { 596 xz_error(state, ret, "lzma error"); 597 return -1; 598 } 599 } while (strm->avail_out && ret != LZMA_STREAM_END); 600 601 /* update available output and crc check value */ 602 state->have = had - strm->avail_out; 603 state->next = strm->next_out - state->have; 604 #ifdef LIBXML_ZLIB_ENABLED 605 state->zstrm.adler = 606 crc32(state->zstrm.adler, state->next, state->have); 607 #endif 608 609 if (ret == LZMA_STREAM_END) { 610 #ifdef LIBXML_ZLIB_ENABLED 611 if (state->how == GZIP) { 612 if (gz_next4(state, &crc) == -1 || gz_next4(state, &len) == -1) { 613 xz_error(state, LZMA_DATA_ERROR, "unexpected end of file"); 614 return -1; 615 } 616 if (crc != state->zstrm.adler) { 617 xz_error(state, LZMA_DATA_ERROR, "incorrect data check"); 618 return -1; 619 } 620 if (len != (state->zstrm.total_out & 0xffffffffL)) { 621 xz_error(state, LZMA_DATA_ERROR, "incorrect length check"); 622 return -1; 623 } 624 state->strm.avail_in = 0; 625 state->strm.next_in = NULL; 626 state->strm.avail_out = 0; 627 state->strm.next_out = NULL; 628 } else 629 #endif 630 if (strm->avail_in != 0 || !state->eof) { 631 xz_error(state, LZMA_DATA_ERROR, "trailing garbage"); 632 return -1; 633 } 634 state->how = LOOK; /* ready for next stream, once have is 0 (leave 635 * state->direct unchanged to remember how) */ 636 } 637 638 /* good decompression */ 639 return 0; 640 } 641 642 static int 643 xz_make(xz_statep state) 644 { 645 lzma_stream *strm = &(state->strm); 646 647 if (state->how == LOOK) { /* look for lzma / gzip header */ 648 if (xz_head(state) == -1) 649 return -1; 650 if (state->have) /* got some data from xz_head() */ 651 return 0; 652 } 653 if (state->how == COPY) { /* straight copy */ 654 if (xz_load(state, state->out, state->size << 1, &(state->have)) == 655 -1) 656 return -1; 657 state->next = state->out; 658 } else if (state->how == LZMA || state->how == GZIP) { /* decompress */ 659 strm->avail_out = state->size << 1; 660 strm->next_out = state->out; 661 if (xz_decomp(state) == -1) 662 return -1; 663 } 664 return 0; 665 } 666 667 static int 668 xz_skip(xz_statep state, uint64_t len) 669 { 670 unsigned n; 671 672 /* skip over len bytes or reach end-of-file, whichever comes first */ 673 while (len) 674 /* skip over whatever is in output buffer */ 675 if (state->have) { 676 n = (uint64_t) state->have > len ? 677 (unsigned) len : state->have; 678 state->have -= n; 679 state->next += n; 680 state->pos += n; 681 len -= n; 682 } 683 684 /* output buffer empty -- return if we're at the end of the input */ 685 else if (state->eof && state->strm.avail_in == 0) 686 break; 687 688 /* need more data to skip -- load up output buffer */ 689 else { 690 /* get more output, looking for header if required */ 691 if (xz_make(state) == -1) 692 return -1; 693 } 694 return 0; 695 } 696 697 int 698 __libxml2_xzread(xzFile file, void *buf, unsigned len) 699 { 700 unsigned got, n; 701 xz_statep state; 702 lzma_stream *strm; 703 704 /* get internal structure */ 705 if (file == NULL) 706 return -1; 707 state = (xz_statep) file; 708 strm = &(state->strm); 709 710 /* check that we're reading and that there's no error */ 711 if (state->err != LZMA_OK) 712 return -1; 713 714 /* since an int is returned, make sure len fits in one, otherwise return 715 * with an error (this avoids the flaw in the interface) */ 716 if ((int) len < 0) { 717 xz_error(state, LZMA_BUF_ERROR, 718 "requested length does not fit in int"); 719 return -1; 720 } 721 722 /* if len is zero, avoid unnecessary operations */ 723 if (len == 0) 724 return 0; 725 726 /* process a skip request */ 727 if (state->seek) { 728 state->seek = 0; 729 if (xz_skip(state, state->skip) == -1) 730 return -1; 731 } 732 733 /* get len bytes to buf, or less than len if at the end */ 734 got = 0; 735 do { 736 /* first just try copying data from the output buffer */ 737 if (state->have) { 738 n = state->have > len ? len : state->have; 739 memcpy(buf, state->next, n); 740 state->next += n; 741 state->have -= n; 742 } 743 744 /* output buffer empty -- return if we're at the end of the input */ 745 else if (state->eof && strm->avail_in == 0) 746 break; 747 748 /* need output data -- for small len or new stream load up our output 749 * buffer */ 750 else if (state->how == LOOK || len < (state->size << 1)) { 751 /* get more output, looking for header if required */ 752 if (xz_make(state) == -1) 753 return -1; 754 continue; /* no progress yet -- go back to memcpy() above */ 755 /* the copy above assures that we will leave with space in the 756 * output buffer, allowing at least one gzungetc() to succeed */ 757 } 758 759 /* large len -- read directly into user buffer */ 760 else if (state->how == COPY) { /* read directly */ 761 if (xz_load(state, buf, len, &n) == -1) 762 return -1; 763 } 764 765 /* large len -- decompress directly into user buffer */ 766 else { /* state->how == LZMA */ 767 strm->avail_out = len; 768 strm->next_out = buf; 769 if (xz_decomp(state) == -1) 770 return -1; 771 n = state->have; 772 state->have = 0; 773 } 774 775 /* update progress */ 776 len -= n; 777 buf = (char *) buf + n; 778 got += n; 779 state->pos += n; 780 } while (len); 781 782 /* return number of bytes read into user buffer (will fit in int) */ 783 return (int) got; 784 } 785 786 int 787 __libxml2_xzclose(xzFile file) 788 { 789 int ret; 790 xz_statep state; 791 792 /* get internal structure */ 793 if (file == NULL) 794 return LZMA_DATA_ERROR; 795 state = (xz_statep) file; 796 797 /* free memory and close file */ 798 if (state->size) { 799 lzma_end(&(state->strm)); 800 #ifdef LIBXML_ZLIB_ENABLED 801 if (state->init == 1) 802 inflateEnd(&(state->zstrm)); 803 state->init = 0; 804 #endif 805 xmlFree(state->out); 806 xmlFree(state->in); 807 } 808 xmlFree(state->path); 809 if ((state->msg != NULL) && (state->err != LZMA_MEM_ERROR)) 810 xmlFree(state->msg); 811 ret = close(state->fd); 812 xmlFree(state); 813 return ret ? ret : LZMA_OK; 814 } 815 #endif /* LIBXML_LZMA_ENABLED */ 816
