buf.c
1 /* 2 * buf.c: memory buffers for libxml2 3 * 4 * new buffer structures and entry points to simplify the maintainance 5 * of libxml2 and ensure we keep good control over memory allocations 6 * and stay 64 bits clean. 7 * The new entry point use the xmlBufPtr opaque structure and 8 * xmlBuf...() counterparts to the old xmlBuf...() functions 9 * 10 * See Copyright for the status of this software. 11 * 12 * daniel@veillard.com 13 */ 14 15 #define IN_LIBXML 16 #include "libxml.h" 17 18 #include <string.h> /* for memset() only ! */ 19 #include <limits.h> 20 #ifdef HAVE_CTYPE_H 21 #include <ctype.h> 22 #endif 23 #ifdef HAVE_STDLIB_H 24 #include <stdlib.h> 25 #endif 26 27 #include <libxml/tree.h> 28 #include <libxml/globals.h> 29 #include <libxml/tree.h> 30 #include <libxml/parserInternals.h> /* for XML_MAX_TEXT_LENGTH */ 31 #include "buf.h" 32 33 #define WITH_BUFFER_COMPAT 34 35 /** 36 * xmlBuf: 37 * 38 * A buffer structure. The base of the structure is somehow compatible 39 * with struct _xmlBuffer to limit risks on application which accessed 40 * directly the input->buf->buffer structures. 41 */ 42 43 struct _xmlBuf { 44 xmlChar *content; /* The buffer content UTF8 */ 45 unsigned int compat_use; /* for binary compatibility */ 46 unsigned int compat_size; /* for binary compatibility */ 47 xmlBufferAllocationScheme alloc; /* The realloc method */ 48 xmlChar *contentIO; /* in IO mode we may have a different base */ 49 size_t use; /* The buffer size used */ 50 size_t size; /* The buffer size */ 51 xmlBufferPtr buffer; /* wrapper for an old buffer */ 52 int error; /* an error code if a failure occurred */ 53 }; 54 55 #ifdef WITH_BUFFER_COMPAT 56 /* 57 * Macro for compatibility with xmlBuffer to be used after an xmlBuf 58 * is updated. This makes sure the compat fields are updated too. 59 */ 60 #define UPDATE_COMPAT(buf) \ 61 if (buf->size < INT_MAX) buf->compat_size = buf->size; \ 62 else buf->compat_size = INT_MAX; \ 63 if (buf->use < INT_MAX) buf->compat_use = buf->use; \ 64 else buf->compat_use = INT_MAX; 65 66 /* 67 * Macro for compatibility with xmlBuffer to be used in all the xmlBuf 68 * entry points, it checks that the compat fields have not been modified 69 * by direct call to xmlBuffer function from code compiled before 2.9.0 . 70 */ 71 #define CHECK_COMPAT(buf) \ 72 if (buf->size != (size_t) buf->compat_size) \ 73 if (buf->compat_size < INT_MAX) \ 74 buf->size = buf->compat_size; \ 75 if (buf->use != (size_t) buf->compat_use) \ 76 if (buf->compat_use < INT_MAX) \ 77 buf->use = buf->compat_use; 78 79 #else /* ! WITH_BUFFER_COMPAT */ 80 #define UPDATE_COMPAT(buf) 81 #define CHECK_COMPAT(buf) 82 #endif /* WITH_BUFFER_COMPAT */ 83 84 /** 85 * xmlBufMemoryError: 86 * @extra: extra informations 87 * 88 * Handle an out of memory condition 89 * To be improved... 90 */ 91 static void 92 xmlBufMemoryError(xmlBufPtr buf, const char *extra) 93 { 94 __xmlSimpleError(XML_FROM_BUFFER, XML_ERR_NO_MEMORY, NULL, NULL, extra); 95 if ((buf) && (buf->error == 0)) 96 buf->error = XML_ERR_NO_MEMORY; 97 } 98 99 /** 100 * xmlBufOverflowError: 101 * @extra: extra informations 102 * 103 * Handle a buffer overflow error 104 * To be improved... 105 */ 106 static void 107 xmlBufOverflowError(xmlBufPtr buf, const char *extra) 108 { 109 __xmlSimpleError(XML_FROM_BUFFER, XML_BUF_OVERFLOW, NULL, NULL, extra); 110 if ((buf) && (buf->error == 0)) 111 buf->error = XML_BUF_OVERFLOW; 112 } 113 114 115 /** 116 * xmlBufCreate: 117 * 118 * routine to create an XML buffer. 119 * returns the new structure. 120 */ 121 xmlBufPtr 122 xmlBufCreate(void) { 123 xmlBufPtr ret; 124 125 ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf)); 126 if (ret == NULL) { 127 xmlBufMemoryError(NULL, "creating buffer"); 128 return(NULL); 129 } 130 ret->compat_use = 0; 131 ret->use = 0; 132 ret->error = 0; 133 ret->buffer = NULL; 134 ret->size = xmlDefaultBufferSize; 135 ret->compat_size = xmlDefaultBufferSize; 136 ret->alloc = xmlBufferAllocScheme; 137 ret->content = (xmlChar *) xmlMallocAtomic(ret->size * sizeof(xmlChar)); 138 if (ret->content == NULL) { 139 xmlBufMemoryError(ret, "creating buffer"); 140 xmlFree(ret); 141 return(NULL); 142 } 143 memset(ret->content, 0, (ret->size * sizeof(xmlChar))); 144 ret->contentIO = NULL; 145 return(ret); 146 } 147 148 /** 149 * xmlBufCreateSize: 150 * @size: initial size of buffer 151 * 152 * routine to create an XML buffer. 153 * returns the new structure. 154 */ 155 xmlBufPtr 156 xmlBufCreateSize(size_t size) { 157 xmlBufPtr ret; 158 159 ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf)); 160 if (ret == NULL) { 161 xmlBufMemoryError(NULL, "creating buffer"); 162 return(NULL); 163 } 164 ret->compat_use = 0; 165 ret->use = 0; 166 ret->error = 0; 167 ret->buffer = NULL; 168 ret->alloc = xmlBufferAllocScheme; 169 ret->size = (size ? size+2 : 0); /* +1 for ending null */ 170 ret->compat_size = (int) ret->size; 171 if (ret->size){ 172 ret->content = (xmlChar *) xmlMallocAtomic(ret->size * sizeof(xmlChar)); 173 if (ret->content == NULL) { 174 xmlBufMemoryError(ret, "creating buffer"); 175 xmlFree(ret); 176 return(NULL); 177 } 178 memset(ret->content, 0, (ret->size * sizeof(xmlChar))); 179 } else 180 ret->content = NULL; 181 ret->contentIO = NULL; 182 return(ret); 183 } 184 185 /** 186 * xmlBufDetach: 187 * @buf: the buffer 188 * 189 * Remove the string contained in a buffer and give it back to the 190 * caller. The buffer is reset to an empty content. 191 * This doesn't work with immutable buffers as they can't be reset. 192 * 193 * Returns the previous string contained by the buffer. 194 */ 195 xmlChar * 196 xmlBufDetach(xmlBufPtr buf) { 197 xmlChar *ret; 198 199 if (buf == NULL) 200 return(NULL); 201 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) 202 return(NULL); 203 if (buf->buffer != NULL) 204 return(NULL); 205 if (buf->error) 206 return(NULL); 207 208 ret = buf->content; 209 buf->content = NULL; 210 buf->size = 0; 211 buf->use = 0; 212 buf->compat_use = 0; 213 buf->compat_size = 0; 214 215 return ret; 216 } 217 218 219 /** 220 * xmlBufCreateStatic: 221 * @mem: the memory area 222 * @size: the size in byte 223 * 224 * routine to create an XML buffer from an immutable memory area. 225 * The area won't be modified nor copied, and is expected to be 226 * present until the end of the buffer lifetime. 227 * 228 * returns the new structure. 229 */ 230 xmlBufPtr 231 xmlBufCreateStatic(void *mem, size_t size) { 232 xmlBufPtr ret; 233 234 if ((mem == NULL) || (size == 0)) 235 return(NULL); 236 237 ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf)); 238 if (ret == NULL) { 239 xmlBufMemoryError(NULL, "creating buffer"); 240 return(NULL); 241 } 242 if (size < INT_MAX) { 243 ret->compat_use = size; 244 ret->compat_size = size; 245 } else { 246 ret->compat_use = INT_MAX; 247 ret->compat_size = INT_MAX; 248 } 249 ret->use = size; 250 ret->size = size; 251 ret->alloc = XML_BUFFER_ALLOC_IMMUTABLE; 252 ret->content = (xmlChar *) mem; 253 ret->error = 0; 254 ret->buffer = NULL; 255 return(ret); 256 } 257 258 /** 259 * xmlBufGetAllocationScheme: 260 * @buf: the buffer 261 * 262 * Get the buffer allocation scheme 263 * 264 * Returns the scheme or -1 in case of error 265 */ 266 int 267 xmlBufGetAllocationScheme(xmlBufPtr buf) { 268 if (buf == NULL) { 269 #ifdef DEBUG_BUFFER 270 xmlGenericError(xmlGenericErrorContext, 271 "xmlBufGetAllocationScheme: buf == NULL\n"); 272 #endif 273 return(-1); 274 } 275 return(buf->alloc); 276 } 277 278 /** 279 * xmlBufSetAllocationScheme: 280 * @buf: the buffer to tune 281 * @scheme: allocation scheme to use 282 * 283 * Sets the allocation scheme for this buffer 284 * 285 * returns 0 in case of success and -1 in case of failure 286 */ 287 int 288 xmlBufSetAllocationScheme(xmlBufPtr buf, 289 xmlBufferAllocationScheme scheme) { 290 if ((buf == NULL) || (buf->error != 0)) { 291 #ifdef DEBUG_BUFFER 292 xmlGenericError(xmlGenericErrorContext, 293 "xmlBufSetAllocationScheme: buf == NULL or in error\n"); 294 #endif 295 return(-1); 296 } 297 if ((buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) || 298 (buf->alloc == XML_BUFFER_ALLOC_IO)) 299 return(-1); 300 if ((scheme == XML_BUFFER_ALLOC_DOUBLEIT) || 301 (scheme == XML_BUFFER_ALLOC_EXACT) || 302 (scheme == XML_BUFFER_ALLOC_HYBRID) || 303 (scheme == XML_BUFFER_ALLOC_IMMUTABLE) || 304 (scheme == XML_BUFFER_ALLOC_BOUNDED)) { 305 buf->alloc = scheme; 306 if (buf->buffer) 307 buf->buffer->alloc = scheme; 308 return(0); 309 } 310 /* 311 * Switching a buffer ALLOC_IO has the side effect of initializing 312 * the contentIO field with the current content 313 */ 314 if (scheme == XML_BUFFER_ALLOC_IO) { 315 buf->alloc = XML_BUFFER_ALLOC_IO; 316 buf->contentIO = buf->content; 317 } 318 return(-1); 319 } 320 321 /** 322 * xmlBufFree: 323 * @buf: the buffer to free 324 * 325 * Frees an XML buffer. It frees both the content and the structure which 326 * encapsulate it. 327 */ 328 void 329 xmlBufFree(xmlBufPtr buf) { 330 if (buf == NULL) { 331 #ifdef DEBUG_BUFFER 332 xmlGenericError(xmlGenericErrorContext, 333 "xmlBufFree: buf == NULL\n"); 334 #endif 335 return; 336 } 337 338 if ((buf->alloc == XML_BUFFER_ALLOC_IO) && 339 (buf->contentIO != NULL)) { 340 xmlFree(buf->contentIO); 341 } else if ((buf->content != NULL) && 342 (buf->alloc != XML_BUFFER_ALLOC_IMMUTABLE)) { 343 xmlFree(buf->content); 344 } 345 xmlFree(buf); 346 } 347 348 /** 349 * xmlBufEmpty: 350 * @buf: the buffer 351 * 352 * empty a buffer. 353 */ 354 void 355 xmlBufEmpty(xmlBufPtr buf) { 356 if ((buf == NULL) || (buf->error != 0)) return; 357 if (buf->content == NULL) return; 358 CHECK_COMPAT(buf) 359 buf->use = 0; 360 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) { 361 buf->content = BAD_CAST ""; 362 } else if ((buf->alloc == XML_BUFFER_ALLOC_IO) && 363 (buf->contentIO != NULL)) { 364 size_t start_buf = buf->content - buf->contentIO; 365 366 buf->size += start_buf; 367 buf->content = buf->contentIO; 368 buf->content[0] = 0; 369 } else { 370 buf->content[0] = 0; 371 } 372 UPDATE_COMPAT(buf) 373 } 374 375 /** 376 * xmlBufShrink: 377 * @buf: the buffer to dump 378 * @len: the number of xmlChar to remove 379 * 380 * Remove the beginning of an XML buffer. 381 * NOTE that this routine behaviour differs from xmlBufferShrink() 382 * as it will return 0 on error instead of -1 due to size_t being 383 * used as the return type. 384 * 385 * Returns the number of byte removed or 0 in case of failure 386 */ 387 size_t 388 xmlBufShrink(xmlBufPtr buf, size_t len) { 389 if ((buf == NULL) || (buf->error != 0)) return(0); 390 CHECK_COMPAT(buf) 391 if (len == 0) return(0); 392 if (len > buf->use) return(0); 393 394 buf->use -= len; 395 if ((buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) || 396 ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL))) { 397 /* 398 * we just move the content pointer, but also make sure 399 * the perceived buffer size has shrinked accordingly 400 */ 401 buf->content += len; 402 buf->size -= len; 403 404 /* 405 * sometimes though it maybe be better to really shrink 406 * on IO buffers 407 */ 408 if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) { 409 size_t start_buf = buf->content - buf->contentIO; 410 if (start_buf >= buf->size) { 411 memmove(buf->contentIO, &buf->content[0], buf->use); 412 buf->content = buf->contentIO; 413 buf->content[buf->use] = 0; 414 buf->size += start_buf; 415 } 416 } 417 } else { 418 memmove(buf->content, &buf->content[len], buf->use); 419 buf->content[buf->use] = 0; 420 buf->size -= len; 421 } 422 UPDATE_COMPAT(buf) 423 return(len); 424 } 425 426 /** 427 * xmlBufGrowInternal: 428 * @buf: the buffer 429 * @len: the minimum free size to allocate 430 * 431 * Grow the available space of an XML buffer, @len is the target value 432 * Error checking should be done on buf->error since using the return 433 * value doesn't work that well 434 * 435 * Returns 0 in case of error or the length made available otherwise 436 */ 437 static size_t 438 xmlBufGrowInternal(xmlBufPtr buf, size_t len) { 439 size_t size; 440 xmlChar *newbuf; 441 442 if ((buf == NULL) || (buf->error != 0)) return(0); 443 CHECK_COMPAT(buf) 444 445 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return(0); 446 if (buf->use + len < buf->size) 447 return(buf->size - buf->use); 448 449 /* 450 * Windows has a BIG problem on realloc timing, so we try to double 451 * the buffer size (if that's enough) (bug 146697) 452 * Apparently BSD too, and it's probably best for linux too 453 * On an embedded system this may be something to change 454 */ 455 #if 1 456 if (buf->size > (size_t) len) 457 size = buf->size * 2; 458 else 459 size = buf->use + len + 100; 460 #else 461 size = buf->use + len + 100; 462 #endif 463 464 if (buf->alloc == XML_BUFFER_ALLOC_BOUNDED) { 465 /* 466 * Used to provide parsing limits 467 */ 468 if ((buf->use + len >= XML_MAX_TEXT_LENGTH) || 469 (buf->size >= XML_MAX_TEXT_LENGTH)) { 470 xmlBufMemoryError(buf, "buffer error: text too long\n"); 471 return(0); 472 } 473 if (size >= XML_MAX_TEXT_LENGTH) 474 size = XML_MAX_TEXT_LENGTH; 475 } 476 if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) { 477 size_t start_buf = buf->content - buf->contentIO; 478 479 newbuf = (xmlChar *) xmlRealloc(buf->contentIO, start_buf + size); 480 if (newbuf == NULL) { 481 xmlBufMemoryError(buf, "growing buffer"); 482 return(0); 483 } 484 buf->contentIO = newbuf; 485 buf->content = newbuf + start_buf; 486 } else { 487 newbuf = (xmlChar *) xmlRealloc(buf->content, size); 488 if (newbuf == NULL) { 489 xmlBufMemoryError(buf, "growing buffer"); 490 return(0); 491 } 492 buf->content = newbuf; 493 } 494 buf->size = size; 495 UPDATE_COMPAT(buf) 496 return(buf->size - buf->use); 497 } 498 499 /** 500 * xmlBufGrow: 501 * @buf: the buffer 502 * @len: the minimum free size to allocate 503 * 504 * Grow the available space of an XML buffer, @len is the target value 505 * This is been kept compatible with xmlBufferGrow() as much as possible 506 * 507 * Returns -1 in case of error or the length made available otherwise 508 */ 509 int 510 xmlBufGrow(xmlBufPtr buf, int len) { 511 size_t ret; 512 513 if ((buf == NULL) || (len < 0)) return(-1); 514 if (len == 0) 515 return(0); 516 ret = xmlBufGrowInternal(buf, len); 517 if (buf->error != 0) 518 return(-1); 519 return((int) ret); 520 } 521 522 /** 523 * xmlBufInflate: 524 * @buf: the buffer 525 * @len: the minimum extra free size to allocate 526 * 527 * Grow the available space of an XML buffer, adding at least @len bytes 528 * 529 * Returns 0 if successful or -1 in case of error 530 */ 531 int 532 xmlBufInflate(xmlBufPtr buf, size_t len) { 533 if (buf == NULL) return(-1); 534 xmlBufGrowInternal(buf, len + buf->size); 535 if (buf->error) 536 return(-1); 537 return(0); 538 } 539 540 /** 541 * xmlBufDump: 542 * @file: the file output 543 * @buf: the buffer to dump 544 * 545 * Dumps an XML buffer to a FILE *. 546 * Returns the number of #xmlChar written 547 */ 548 size_t 549 xmlBufDump(FILE *file, xmlBufPtr buf) { 550 size_t ret; 551 552 if ((buf == NULL) || (buf->error != 0)) { 553 #ifdef DEBUG_BUFFER 554 xmlGenericError(xmlGenericErrorContext, 555 "xmlBufDump: buf == NULL or in error\n"); 556 #endif 557 return(0); 558 } 559 if (buf->content == NULL) { 560 #ifdef DEBUG_BUFFER 561 xmlGenericError(xmlGenericErrorContext, 562 "xmlBufDump: buf->content == NULL\n"); 563 #endif 564 return(0); 565 } 566 CHECK_COMPAT(buf) 567 if (file == NULL) 568 file = stdout; 569 ret = fwrite(buf->content, sizeof(xmlChar), buf->use, file); 570 return(ret); 571 } 572 573 /** 574 * xmlBufContent: 575 * @buf: the buffer 576 * 577 * Function to extract the content of a buffer 578 * 579 * Returns the internal content 580 */ 581 582 xmlChar * 583 xmlBufContent(const xmlBuf *buf) 584 { 585 if ((!buf) || (buf->error)) 586 return NULL; 587 588 return(buf->content); 589 } 590 591 /** 592 * xmlBufEnd: 593 * @buf: the buffer 594 * 595 * Function to extract the end of the content of a buffer 596 * 597 * Returns the end of the internal content or NULL in case of error 598 */ 599 600 xmlChar * 601 xmlBufEnd(xmlBufPtr buf) 602 { 603 if ((!buf) || (buf->error)) 604 return NULL; 605 CHECK_COMPAT(buf) 606 607 return(&buf->content[buf->use]); 608 } 609 610 /** 611 * xmlBufAddLen: 612 * @buf: the buffer 613 * @len: the size which were added at the end 614 * 615 * Sometime data may be added at the end of the buffer without 616 * using the xmlBuf APIs that is used to expand the used space 617 * and set the zero terminating at the end of the buffer 618 * 619 * Returns -1 in case of error and 0 otherwise 620 */ 621 int 622 xmlBufAddLen(xmlBufPtr buf, size_t len) { 623 if ((buf == NULL) || (buf->error)) 624 return(-1); 625 CHECK_COMPAT(buf) 626 if (len > (buf->size - buf->use)) 627 return(-1); 628 buf->use += len; 629 UPDATE_COMPAT(buf) 630 if (buf->size > buf->use) 631 buf->content[buf->use] = 0; 632 else 633 return(-1); 634 return(0); 635 } 636 637 /** 638 * xmlBufErase: 639 * @buf: the buffer 640 * @len: the size to erase at the end 641 * 642 * Sometime data need to be erased at the end of the buffer 643 * 644 * Returns -1 in case of error and 0 otherwise 645 */ 646 int 647 xmlBufErase(xmlBufPtr buf, size_t len) { 648 if ((buf == NULL) || (buf->error)) 649 return(-1); 650 CHECK_COMPAT(buf) 651 if (len > buf->use) 652 return(-1); 653 buf->use -= len; 654 buf->content[buf->use] = 0; 655 UPDATE_COMPAT(buf) 656 return(0); 657 } 658 659 /** 660 * xmlBufLength: 661 * @buf: the buffer 662 * 663 * Function to get the length of a buffer 664 * 665 * Returns the length of data in the internal content 666 */ 667 668 size_t 669 xmlBufLength(const xmlBufPtr buf) 670 { 671 if ((!buf) || (buf->error)) 672 return 0; 673 CHECK_COMPAT(buf) 674 675 return(buf->use); 676 } 677 678 /** 679 * xmlBufUse: 680 * @buf: the buffer 681 * 682 * Function to get the length of a buffer 683 * 684 * Returns the length of data in the internal content 685 */ 686 687 size_t 688 xmlBufUse(const xmlBufPtr buf) 689 { 690 if ((!buf) || (buf->error)) 691 return 0; 692 CHECK_COMPAT(buf) 693 694 return(buf->use); 695 } 696 697 /** 698 * xmlBufAvail: 699 * @buf: the buffer 700 * 701 * Function to find how much free space is allocated but not 702 * used in the buffer. It does not account for the terminating zero 703 * usually needed 704 * 705 * Returns the amount or 0 if none or an error occurred 706 */ 707 708 size_t 709 xmlBufAvail(const xmlBufPtr buf) 710 { 711 if ((!buf) || (buf->error)) 712 return 0; 713 CHECK_COMPAT(buf) 714 715 return(buf->size - buf->use); 716 } 717 718 /** 719 * xmlBufIsEmpty: 720 * @buf: the buffer 721 * 722 * Tell if a buffer is empty 723 * 724 * Returns 0 if no, 1 if yes and -1 in case of error 725 */ 726 int 727 xmlBufIsEmpty(const xmlBufPtr buf) 728 { 729 if ((!buf) || (buf->error)) 730 return(-1); 731 CHECK_COMPAT(buf) 732 733 return(buf->use == 0); 734 } 735 736 /** 737 * xmlBufResize: 738 * @buf: the buffer to resize 739 * @size: the desired size 740 * 741 * Resize a buffer to accommodate minimum size of @size. 742 * 743 * Returns 0 in case of problems, 1 otherwise 744 */ 745 int 746 xmlBufResize(xmlBufPtr buf, size_t size) 747 { 748 unsigned int newSize; 749 xmlChar* rebuf = NULL; 750 size_t start_buf; 751 752 if ((buf == NULL) || (buf->error)) 753 return(0); 754 CHECK_COMPAT(buf) 755 756 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return(0); 757 if (buf->alloc == XML_BUFFER_ALLOC_BOUNDED) { 758 /* 759 * Used to provide parsing limits 760 */ 761 if (size >= XML_MAX_TEXT_LENGTH) { 762 xmlBufMemoryError(buf, "buffer error: text too long\n"); 763 return(0); 764 } 765 } 766 767 /* Don't resize if we don't have to */ 768 if (size < buf->size) 769 return 1; 770 771 /* figure out new size */ 772 switch (buf->alloc){ 773 case XML_BUFFER_ALLOC_IO: 774 case XML_BUFFER_ALLOC_DOUBLEIT: 775 /*take care of empty case*/ 776 newSize = (buf->size ? buf->size*2 : size + 10); 777 while (size > newSize) { 778 if (newSize > UINT_MAX / 2) { 779 xmlBufMemoryError(buf, "growing buffer"); 780 return 0; 781 } 782 newSize *= 2; 783 } 784 break; 785 case XML_BUFFER_ALLOC_EXACT: 786 newSize = size+10; 787 break; 788 case XML_BUFFER_ALLOC_HYBRID: 789 if (buf->use < BASE_BUFFER_SIZE) 790 newSize = size; 791 else { 792 newSize = buf->size * 2; 793 while (size > newSize) { 794 if (newSize > UINT_MAX / 2) { 795 xmlBufMemoryError(buf, "growing buffer"); 796 return 0; 797 } 798 newSize *= 2; 799 } 800 } 801 break; 802 803 default: 804 newSize = size+10; 805 break; 806 } 807 808 if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) { 809 start_buf = buf->content - buf->contentIO; 810 811 if (start_buf > newSize) { 812 /* move data back to start */ 813 memmove(buf->contentIO, buf->content, buf->use); 814 buf->content = buf->contentIO; 815 buf->content[buf->use] = 0; 816 buf->size += start_buf; 817 } else { 818 rebuf = (xmlChar *) xmlRealloc(buf->contentIO, start_buf + newSize); 819 if (rebuf == NULL) { 820 xmlBufMemoryError(buf, "growing buffer"); 821 return 0; 822 } 823 buf->contentIO = rebuf; 824 buf->content = rebuf + start_buf; 825 } 826 } else { 827 if (buf->content == NULL) { 828 rebuf = (xmlChar *) xmlMallocAtomic(newSize); 829 } else if (buf->size - buf->use < 100) { 830 rebuf = (xmlChar *) xmlRealloc(buf->content, newSize); 831 } else { 832 /* 833 * if we are reallocating a buffer far from being full, it's 834 * better to make a new allocation and copy only the used range 835 * and free the old one. 836 */ 837 rebuf = (xmlChar *) xmlMallocAtomic(newSize); 838 if (rebuf != NULL) { 839 memcpy(rebuf, buf->content, buf->use); 840 xmlFree(buf->content); 841 rebuf[buf->use] = 0; 842 } 843 } 844 if (rebuf == NULL) { 845 xmlBufMemoryError(buf, "growing buffer"); 846 return 0; 847 } 848 buf->content = rebuf; 849 } 850 buf->size = newSize; 851 UPDATE_COMPAT(buf) 852 853 return 1; 854 } 855 856 /** 857 * xmlBufAdd: 858 * @buf: the buffer to dump 859 * @str: the #xmlChar string 860 * @len: the number of #xmlChar to add 861 * 862 * Add a string range to an XML buffer. if len == -1, the length of 863 * str is recomputed. 864 * 865 * Returns 0 successful, a positive error code number otherwise 866 * and -1 in case of internal or API error. 867 */ 868 int 869 xmlBufAdd(xmlBufPtr buf, const xmlChar *str, int len) { 870 unsigned int needSize; 871 872 if ((str == NULL) || (buf == NULL) || (buf->error)) 873 return -1; 874 CHECK_COMPAT(buf) 875 876 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1; 877 if (len < -1) { 878 #ifdef DEBUG_BUFFER 879 xmlGenericError(xmlGenericErrorContext, 880 "xmlBufAdd: len < 0\n"); 881 #endif 882 return -1; 883 } 884 if (len == 0) return 0; 885 886 if (len < 0) 887 len = xmlStrlen(str); 888 889 if (len < 0) return -1; 890 if (len == 0) return 0; 891 892 needSize = buf->use + len + 2; 893 if (needSize > buf->size){ 894 if (buf->alloc == XML_BUFFER_ALLOC_BOUNDED) { 895 /* 896 * Used to provide parsing limits 897 */ 898 if (needSize >= XML_MAX_TEXT_LENGTH) { 899 xmlBufMemoryError(buf, "buffer error: text too long\n"); 900 return(-1); 901 } 902 } 903 if (!xmlBufResize(buf, needSize)){ 904 xmlBufMemoryError(buf, "growing buffer"); 905 return XML_ERR_NO_MEMORY; 906 } 907 } 908 909 memmove(&buf->content[buf->use], str, len*sizeof(xmlChar)); 910 buf->use += len; 911 buf->content[buf->use] = 0; 912 UPDATE_COMPAT(buf) 913 return 0; 914 } 915 916 /** 917 * xmlBufAddHead: 918 * @buf: the buffer 919 * @str: the #xmlChar string 920 * @len: the number of #xmlChar to add 921 * 922 * Add a string range to the beginning of an XML buffer. 923 * if len == -1, the length of @str is recomputed. 924 * 925 * Returns 0 successful, a positive error code number otherwise 926 * and -1 in case of internal or API error. 927 */ 928 int 929 xmlBufAddHead(xmlBufPtr buf, const xmlChar *str, int len) { 930 unsigned int needSize; 931 932 if ((buf == NULL) || (buf->error)) 933 return(-1); 934 CHECK_COMPAT(buf) 935 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1; 936 if (str == NULL) { 937 #ifdef DEBUG_BUFFER 938 xmlGenericError(xmlGenericErrorContext, 939 "xmlBufAddHead: str == NULL\n"); 940 #endif 941 return -1; 942 } 943 if (len < -1) { 944 #ifdef DEBUG_BUFFER 945 xmlGenericError(xmlGenericErrorContext, 946 "xmlBufAddHead: len < 0\n"); 947 #endif 948 return -1; 949 } 950 if (len == 0) return 0; 951 952 if (len < 0) 953 len = xmlStrlen(str); 954 955 if (len <= 0) return -1; 956 957 if ((buf->alloc == XML_BUFFER_ALLOC_IO) && (buf->contentIO != NULL)) { 958 size_t start_buf = buf->content - buf->contentIO; 959 960 if (start_buf > (unsigned int) len) { 961 /* 962 * We can add it in the space previously shrinked 963 */ 964 buf->content -= len; 965 memmove(&buf->content[0], str, len); 966 buf->use += len; 967 buf->size += len; 968 UPDATE_COMPAT(buf) 969 return(0); 970 } 971 } 972 needSize = buf->use + len + 2; 973 if (needSize > buf->size){ 974 if (buf->alloc == XML_BUFFER_ALLOC_BOUNDED) { 975 /* 976 * Used to provide parsing limits 977 */ 978 if (needSize >= XML_MAX_TEXT_LENGTH) { 979 xmlBufMemoryError(buf, "buffer error: text too long\n"); 980 return(-1); 981 } 982 } 983 if (!xmlBufResize(buf, needSize)){ 984 xmlBufMemoryError(buf, "growing buffer"); 985 return XML_ERR_NO_MEMORY; 986 } 987 } 988 989 memmove(&buf->content[len], &buf->content[0], buf->use); 990 memmove(&buf->content[0], str, len); 991 buf->use += len; 992 buf->content[buf->use] = 0; 993 UPDATE_COMPAT(buf) 994 return 0; 995 } 996 997 /** 998 * xmlBufCat: 999 * @buf: the buffer to add to 1000 * @str: the #xmlChar string 1001 * 1002 * Append a zero terminated string to an XML buffer. 1003 * 1004 * Returns 0 successful, a positive error code number otherwise 1005 * and -1 in case of internal or API error. 1006 */ 1007 int 1008 xmlBufCat(xmlBufPtr buf, const xmlChar *str) { 1009 if ((buf == NULL) || (buf->error)) 1010 return(-1); 1011 CHECK_COMPAT(buf) 1012 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1; 1013 if (str == NULL) return -1; 1014 return xmlBufAdd(buf, str, -1); 1015 } 1016 1017 /** 1018 * xmlBufCCat: 1019 * @buf: the buffer to dump 1020 * @str: the C char string 1021 * 1022 * Append a zero terminated C string to an XML buffer. 1023 * 1024 * Returns 0 successful, a positive error code number otherwise 1025 * and -1 in case of internal or API error. 1026 */ 1027 int 1028 xmlBufCCat(xmlBufPtr buf, const char *str) { 1029 const char *cur; 1030 1031 if ((buf == NULL) || (buf->error)) 1032 return(-1); 1033 CHECK_COMPAT(buf) 1034 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) return -1; 1035 if (str == NULL) { 1036 #ifdef DEBUG_BUFFER 1037 xmlGenericError(xmlGenericErrorContext, 1038 "xmlBufCCat: str == NULL\n"); 1039 #endif 1040 return -1; 1041 } 1042 for (cur = str;*cur != 0;cur++) { 1043 if (buf->use + 10 >= buf->size) { 1044 if (!xmlBufResize(buf, buf->use+10)){ 1045 xmlBufMemoryError(buf, "growing buffer"); 1046 return XML_ERR_NO_MEMORY; 1047 } 1048 } 1049 buf->content[buf->use++] = *cur; 1050 } 1051 buf->content[buf->use] = 0; 1052 UPDATE_COMPAT(buf) 1053 return 0; 1054 } 1055 1056 /** 1057 * xmlBufWriteCHAR: 1058 * @buf: the XML buffer 1059 * @string: the string to add 1060 * 1061 * routine which manages and grows an output buffer. This one adds 1062 * xmlChars at the end of the buffer. 1063 * 1064 * Returns 0 if successful, a positive error code number otherwise 1065 * and -1 in case of internal or API error. 1066 */ 1067 int 1068 xmlBufWriteCHAR(xmlBufPtr buf, const xmlChar *string) { 1069 if ((buf == NULL) || (buf->error)) 1070 return(-1); 1071 CHECK_COMPAT(buf) 1072 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) 1073 return(-1); 1074 return(xmlBufCat(buf, string)); 1075 } 1076 1077 /** 1078 * xmlBufWriteChar: 1079 * @buf: the XML buffer output 1080 * @string: the string to add 1081 * 1082 * routine which manage and grows an output buffer. This one add 1083 * C chars at the end of the array. 1084 * 1085 * Returns 0 if successful, a positive error code number otherwise 1086 * and -1 in case of internal or API error. 1087 */ 1088 int 1089 xmlBufWriteChar(xmlBufPtr buf, const char *string) { 1090 if ((buf == NULL) || (buf->error)) 1091 return(-1); 1092 CHECK_COMPAT(buf) 1093 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) 1094 return(-1); 1095 return(xmlBufCCat(buf, string)); 1096 } 1097 1098 1099 /** 1100 * xmlBufWriteQuotedString: 1101 * @buf: the XML buffer output 1102 * @string: the string to add 1103 * 1104 * routine which manage and grows an output buffer. This one writes 1105 * a quoted or double quoted #xmlChar string, checking first if it holds 1106 * quote or double-quotes internally 1107 * 1108 * Returns 0 if successful, a positive error code number otherwise 1109 * and -1 in case of internal or API error. 1110 */ 1111 int 1112 xmlBufWriteQuotedString(xmlBufPtr buf, const xmlChar *string) { 1113 const xmlChar *cur, *base; 1114 if ((buf == NULL) || (buf->error)) 1115 return(-1); 1116 CHECK_COMPAT(buf) 1117 if (buf->alloc == XML_BUFFER_ALLOC_IMMUTABLE) 1118 return(-1); 1119 if (xmlStrchr(string, '\"')) { 1120 if (xmlStrchr(string, '\'')) { 1121 #ifdef DEBUG_BUFFER 1122 xmlGenericError(xmlGenericErrorContext, 1123 "xmlBufWriteQuotedString: string contains quote and double-quotes !\n"); 1124 #endif 1125 xmlBufCCat(buf, "\""); 1126 base = cur = string; 1127 while(*cur != 0){ 1128 if(*cur == '"'){ 1129 if (base != cur) 1130 xmlBufAdd(buf, base, cur - base); 1131 xmlBufAdd(buf, BAD_CAST """, 6); 1132 cur++; 1133 base = cur; 1134 } 1135 else { 1136 cur++; 1137 } 1138 } 1139 if (base != cur) 1140 xmlBufAdd(buf, base, cur - base); 1141 xmlBufCCat(buf, "\""); 1142 } 1143 else{ 1144 xmlBufCCat(buf, "\'"); 1145 xmlBufCat(buf, string); 1146 xmlBufCCat(buf, "\'"); 1147 } 1148 } else { 1149 xmlBufCCat(buf, "\""); 1150 xmlBufCat(buf, string); 1151 xmlBufCCat(buf, "\""); 1152 } 1153 return(0); 1154 } 1155 1156 /** 1157 * xmlBufFromBuffer: 1158 * @buffer: incoming old buffer to convert to a new one 1159 * 1160 * Helper routine to switch from the old buffer structures in use 1161 * in various APIs. It creates a wrapper xmlBufPtr which will be 1162 * used for internal processing until the xmlBufBackToBuffer() is 1163 * issued. 1164 * 1165 * Returns a new xmlBufPtr unless the call failed and NULL is returned 1166 */ 1167 xmlBufPtr 1168 xmlBufFromBuffer(xmlBufferPtr buffer) { 1169 xmlBufPtr ret; 1170 1171 if (buffer == NULL) 1172 return(NULL); 1173 1174 ret = (xmlBufPtr) xmlMalloc(sizeof(xmlBuf)); 1175 if (ret == NULL) { 1176 xmlBufMemoryError(NULL, "creating buffer"); 1177 return(NULL); 1178 } 1179 ret->use = buffer->use; 1180 ret->size = buffer->size; 1181 ret->compat_use = buffer->use; 1182 ret->compat_size = buffer->size; 1183 ret->error = 0; 1184 ret->buffer = buffer; 1185 ret->alloc = buffer->alloc; 1186 ret->content = buffer->content; 1187 ret->contentIO = buffer->contentIO; 1188 1189 return(ret); 1190 } 1191 1192 /** 1193 * xmlBufBackToBuffer: 1194 * @buf: new buffer wrapping the old one 1195 * 1196 * Function to be called once internal processing had been done to 1197 * update back the buffer provided by the user. This can lead to 1198 * a failure in case the size accumulated in the xmlBuf is larger 1199 * than what an xmlBuffer can support on 64 bits (INT_MAX) 1200 * The xmlBufPtr @buf wrapper is deallocated by this call in any case. 1201 * 1202 * Returns the old xmlBufferPtr unless the call failed and NULL is returned 1203 */ 1204 xmlBufferPtr 1205 xmlBufBackToBuffer(xmlBufPtr buf) { 1206 xmlBufferPtr ret; 1207 1208 if ((buf == NULL) || (buf->error)) 1209 return(NULL); 1210 CHECK_COMPAT(buf) 1211 if (buf->buffer == NULL) { 1212 xmlBufFree(buf); 1213 return(NULL); 1214 } 1215 1216 ret = buf->buffer; 1217 /* 1218 * What to do in case of error in the buffer ??? 1219 */ 1220 if (buf->use > INT_MAX) { 1221 /* 1222 * Worse case, we really allocated and used more than the 1223 * maximum allowed memory for an xmlBuffer on this architecture. 1224 * Keep the buffer but provide a truncated size value. 1225 */ 1226 xmlBufOverflowError(buf, "Used size too big for xmlBuffer"); 1227 ret->use = INT_MAX; 1228 ret->size = INT_MAX; 1229 } else if (buf->size > INT_MAX) { 1230 /* 1231 * milder case, we allocated more than the maximum allowed memory 1232 * for an xmlBuffer on this architecture, but used less than the 1233 * limit. 1234 * Keep the buffer but provide a truncated size value. 1235 */ 1236 xmlBufOverflowError(buf, "Allocated size too big for xmlBuffer"); 1237 ret->use = (int) buf->use; 1238 ret->size = INT_MAX; 1239 } else { 1240 ret->use = (int) buf->use; 1241 ret->size = (int) buf->size; 1242 } 1243 ret->alloc = buf->alloc; 1244 ret->content = buf->content; 1245 ret->contentIO = buf->contentIO; 1246 xmlFree(buf); 1247 return(ret); 1248 } 1249 1250 /** 1251 * xmlBufMergeBuffer: 1252 * @buf: an xmlBufPtr 1253 * @buffer: the buffer to consume into @buf 1254 * 1255 * The content of @buffer is appended to @buf and @buffer is freed 1256 * 1257 * Returns -1 in case of error, 0 otherwise, in any case @buffer is freed 1258 */ 1259 int 1260 xmlBufMergeBuffer(xmlBufPtr buf, xmlBufferPtr buffer) { 1261 int ret = 0; 1262 1263 if ((buf == NULL) || (buf->error)) { 1264 xmlBufferFree(buffer); 1265 return(-1); 1266 } 1267 CHECK_COMPAT(buf) 1268 if ((buffer != NULL) && (buffer->content != NULL) && 1269 (buffer->use > 0)) { 1270 ret = xmlBufAdd(buf, buffer->content, buffer->use); 1271 } 1272 xmlBufferFree(buffer); 1273 return(ret); 1274 } 1275 1276 /** 1277 * xmlBufResetInput: 1278 * @buf: an xmlBufPtr 1279 * @input: an xmlParserInputPtr 1280 * 1281 * Update the input to use the current set of pointers from the buffer. 1282 * 1283 * Returns -1 in case of error, 0 otherwise 1284 */ 1285 int 1286 xmlBufResetInput(xmlBufPtr buf, xmlParserInputPtr input) { 1287 if ((input == NULL) || (buf == NULL) || (buf->error)) 1288 return(-1); 1289 CHECK_COMPAT(buf) 1290 input->base = input->cur = buf->content; 1291 input->end = &buf->content[buf->use]; 1292 return(0); 1293 } 1294 1295 /** 1296 * xmlBufGetInputBase: 1297 * @buf: an xmlBufPtr 1298 * @input: an xmlParserInputPtr 1299 * 1300 * Get the base of the @input relative to the beginning of the buffer 1301 * 1302 * Returns the size_t corresponding to the displacement 1303 */ 1304 size_t 1305 xmlBufGetInputBase(xmlBufPtr buf, xmlParserInputPtr input) { 1306 size_t base; 1307 1308 if ((input == NULL) || (buf == NULL) || (buf->error)) 1309 return(-1); 1310 CHECK_COMPAT(buf) 1311 base = input->base - buf->content; 1312 /* 1313 * We could do some pointer arythmetic checks but that's probably 1314 * sufficient. 1315 */ 1316 if (base > buf->size) { 1317 xmlBufOverflowError(buf, "Input reference outside of the buffer"); 1318 base = 0; 1319 } 1320 return(base); 1321 } 1322 1323 /** 1324 * xmlBufSetInputBaseCur: 1325 * @buf: an xmlBufPtr 1326 * @input: an xmlParserInputPtr 1327 * @base: the base value relative to the beginning of the buffer 1328 * @cur: the cur value relative to the beginning of the buffer 1329 * 1330 * Update the input to use the base and cur relative to the buffer 1331 * after a possible reallocation of its content 1332 * 1333 * Returns -1 in case of error, 0 otherwise 1334 */ 1335 int 1336 xmlBufSetInputBaseCur(xmlBufPtr buf, xmlParserInputPtr input, 1337 size_t base, size_t cur) { 1338 if (input == NULL) 1339 return(-1); 1340 if ((buf == NULL) || (buf->error)) { 1341 input->base = input->cur = input->end = BAD_CAST ""; 1342 return(-1); 1343 } 1344 CHECK_COMPAT(buf) 1345 input->base = &buf->content[base]; 1346 input->cur = input->base + cur; 1347 input->end = &buf->content[buf->use]; 1348 return(0); 1349 } 1350 1351 #define bottom_buf 1352 #include "elfgcchack.h"