1 /* 2 * string.c : an XML string utilities module 3 * 4 * This module provides various utility functions for manipulating 5 * the xmlChar* type. All functions named xmlStr* have been moved here 6 * from the parser.c file (their original home). 7 * 8 * See Copyright for the status of this software. 9 * 10 * UTF8 string routines from: 11 * William Brack <wbrack (at) mmm.com.hk> 12 * 13 * daniel (at) veillard.com 14 */ 15 16 #define IN_LIBXML 17 #include "libxml.h" 18 19 #include <stdlib.h> 20 #include <string.h> 21 #include <libxml/xmlmemory.h> 22 #include <libxml/parserInternals.h> 23 #include <libxml/xmlstring.h> 24 25 /************************************************************************ 26 * * 27 * Commodity functions to handle xmlChars * 28 * * 29 ************************************************************************/ 30 31 /** 32 * xmlStrndup: 33 * @cur: the input xmlChar * 34 * @len: the len of @cur 35 * 36 * a strndup for array of xmlChar's 37 * 38 * Returns a new xmlChar * or NULL 39 */ 40 xmlChar * 41 xmlStrndup(const xmlChar *cur, int len) { 42 xmlChar *ret; 43 44 if ((cur == NULL) || (len < 0)) return(NULL); 45 ret = (xmlChar *) xmlMallocAtomic((len + 1) * sizeof(xmlChar)); 46 if (ret == NULL) { 47 xmlErrMemory(NULL, NULL); 48 return(NULL); 49 } 50 memcpy(ret, cur, len * sizeof(xmlChar)); 51 ret[len] = 0; 52 return(ret); 53 } 54 55 /** 56 * xmlStrdup: 57 * @cur: the input xmlChar * 58 * 59 * a strdup for array of xmlChar's. Since they are supposed to be 60 * encoded in UTF-8 or an encoding with 8bit based chars, we assume 61 * a termination mark of '0'. 62 * 63 * Returns a new xmlChar * or NULL 64 */ 65 xmlChar * 66 xmlStrdup(const xmlChar *cur) { 67 const xmlChar *p = cur; 68 69 if (cur == NULL) return(NULL); 70 while (*p != 0) p++; /* non input consuming */ 71 return(xmlStrndup(cur, p - cur)); 72 } 73 74 /** 75 * xmlCharStrndup: 76 * @cur: the input char * 77 * @len: the len of @cur 78 * 79 * a strndup for char's to xmlChar's 80 * 81 * Returns a new xmlChar * or NULL 82 */ 83 84 xmlChar * 85 xmlCharStrndup(const char *cur, int len) { 86 int i; 87 xmlChar *ret; 88 89 if ((cur == NULL) || (len < 0)) return(NULL); 90 ret = (xmlChar *) xmlMallocAtomic((len + 1) * sizeof(xmlChar)); 91 if (ret == NULL) { 92 xmlErrMemory(NULL, NULL); 93 return(NULL); 94 } 95 for (i = 0;i < len;i++) { 96 ret[i] = (xmlChar) cur[i]; 97 if (ret[i] == 0) return(ret); 98 } 99 ret[len] = 0; 100 return(ret); 101 } 102 103 /** 104 * xmlCharStrdup: 105 * @cur: the input char * 106 * 107 * a strdup for char's to xmlChar's 108 * 109 * Returns a new xmlChar * or NULL 110 */ 111 112 xmlChar * 113 xmlCharStrdup(const char *cur) { 114 const char *p = cur; 115 116 if (cur == NULL) return(NULL); 117 while (*p != '\0') p++; /* non input consuming */ 118 return(xmlCharStrndup(cur, p - cur)); 119 } 120 121 /** 122 * xmlStrcmp: 123 * @str1: the first xmlChar * 124 * @str2: the second xmlChar * 125 * 126 * a strcmp for xmlChar's 127 * 128 * Returns the integer result of the comparison 129 */ 130 131 int 132 xmlStrcmp(const xmlChar *str1, const xmlChar *str2) { 133 register int tmp; 134 135 if (str1 == str2) return(0); 136 if (str1 == NULL) return(-1); 137 if (str2 == NULL) return(1); 138 do { 139 tmp = *str1++ - *str2; 140 if (tmp != 0) return(tmp); 141 } while (*str2++ != 0); 142 return 0; 143 } 144 145 /** 146 * xmlStrEqual: 147 * @str1: the first xmlChar * 148 * @str2: the second xmlChar * 149 * 150 * Check if both strings are equal of have same content. 151 * Should be a bit more readable and faster than xmlStrcmp() 152 * 153 * Returns 1 if they are equal, 0 if they are different 154 */ 155 156 int 157 xmlStrEqual(const xmlChar *str1, const xmlChar *str2) { 158 if (str1 == str2) return(1); 159 if (str1 == NULL) return(0); 160 if (str2 == NULL) return(0); 161 do { 162 if (*str1++ != *str2) return(0); 163 } while (*str2++); 164 return(1); 165 } 166 167 /** 168 * xmlStrQEqual: 169 * @pref: the prefix of the QName 170 * @name: the localname of the QName 171 * @str: the second xmlChar * 172 * 173 * Check if a QName is Equal to a given string 174 * 175 * Returns 1 if they are equal, 0 if they are different 176 */ 177 178 int 179 xmlStrQEqual(const xmlChar *pref, const xmlChar *name, const xmlChar *str) { 180 if (pref == NULL) return(xmlStrEqual(name, str)); 181 if (name == NULL) return(0); 182 if (str == NULL) return(0); 183 184 do { 185 if (*pref++ != *str) return(0); 186 } while ((*str++) && (*pref)); 187 if (*str++ != ':') return(0); 188 do { 189 if (*name++ != *str) return(0); 190 } while (*str++); 191 return(1); 192 } 193 194 /** 195 * xmlStrncmp: 196 * @str1: the first xmlChar * 197 * @str2: the second xmlChar * 198 * @len: the max comparison length 199 * 200 * a strncmp for xmlChar's 201 * 202 * Returns the integer result of the comparison 203 */ 204 205 int 206 xmlStrncmp(const xmlChar *str1, const xmlChar *str2, int len) { 207 register int tmp; 208 209 if (len <= 0) return(0); 210 if (str1 == str2) return(0); 211 if (str1 == NULL) return(-1); 212 if (str2 == NULL) return(1); 213 #ifdef __GNUC__ 214 tmp = strncmp((const char *)str1, (const char *)str2, len); 215 return tmp; 216 #else 217 do { 218 tmp = *str1++ - *str2; 219 if (tmp != 0 || --len == 0) return(tmp); 220 } while (*str2++ != 0); 221 return 0; 222 #endif 223 } 224 225 static const xmlChar casemap[256] = { 226 0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07, 227 0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F, 228 0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17, 229 0x18,0x19,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F, 230 0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27, 231 0x28,0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F, 232 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37, 233 0x38,0x39,0x3A,0x3B,0x3C,0x3D,0x3E,0x3F, 234 0x40,0x61,0x62,0x63,0x64,0x65,0x66,0x67, 235 0x68,0x69,0x6A,0x6B,0x6C,0x6D,0x6E,0x6F, 236 0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77, 237 0x78,0x79,0x7A,0x7B,0x5C,0x5D,0x5E,0x5F, 238 0x60,0x61,0x62,0x63,0x64,0x65,0x66,0x67, 239 0x68,0x69,0x6A,0x6B,0x6C,0x6D,0x6E,0x6F, 240 0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77, 241 0x78,0x79,0x7A,0x7B,0x7C,0x7D,0x7E,0x7F, 242 0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87, 243 0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F, 244 0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97, 245 0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, 246 0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7, 247 0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF, 248 0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7, 249 0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, 250 0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7, 251 0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF, 252 0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7, 253 0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, 254 0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7, 255 0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF, 256 0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7, 257 0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF 258 }; 259 260 /** 261 * xmlStrcasecmp: 262 * @str1: the first xmlChar * 263 * @str2: the second xmlChar * 264 * 265 * a strcasecmp for xmlChar's 266 * 267 * Returns the integer result of the comparison 268 */ 269 270 int 271 xmlStrcasecmp(const xmlChar *str1, const xmlChar *str2) { 272 register int tmp; 273 274 if (str1 == str2) return(0); 275 if (str1 == NULL) return(-1); 276 if (str2 == NULL) return(1); 277 do { 278 tmp = casemap[*str1++] - casemap[*str2]; 279 if (tmp != 0) return(tmp); 280 } while (*str2++ != 0); 281 return 0; 282 } 283 284 /** 285 * xmlStrncasecmp: 286 * @str1: the first xmlChar * 287 * @str2: the second xmlChar * 288 * @len: the max comparison length 289 * 290 * a strncasecmp for xmlChar's 291 * 292 * Returns the integer result of the comparison 293 */ 294 295 int 296 xmlStrncasecmp(const xmlChar *str1, const xmlChar *str2, int len) { 297 register int tmp; 298 299 if (len <= 0) return(0); 300 if (str1 == str2) return(0); 301 if (str1 == NULL) return(-1); 302 if (str2 == NULL) return(1); 303 do { 304 tmp = casemap[*str1++] - casemap[*str2]; 305 if (tmp != 0 || --len == 0) return(tmp); 306 } while (*str2++ != 0); 307 return 0; 308 } 309 310 /** 311 * xmlStrchr: 312 * @str: the xmlChar * array 313 * @val: the xmlChar to search 314 * 315 * a strchr for xmlChar's 316 * 317 * Returns the xmlChar * for the first occurrence or NULL. 318 */ 319 320 const xmlChar * 321 xmlStrchr(const xmlChar *str, xmlChar val) { 322 if (str == NULL) return(NULL); 323 while (*str != 0) { /* non input consuming */ 324 if (*str == val) return((xmlChar *) str); 325 str++; 326 } 327 return(NULL); 328 } 329 330 /** 331 * xmlStrstr: 332 * @str: the xmlChar * array (haystack) 333 * @val: the xmlChar to search (needle) 334 * 335 * a strstr for xmlChar's 336 * 337 * Returns the xmlChar * for the first occurrence or NULL. 338 */ 339 340 const xmlChar * 341 xmlStrstr(const xmlChar *str, const xmlChar *val) { 342 int n; 343 344 if (str == NULL) return(NULL); 345 if (val == NULL) return(NULL); 346 n = xmlStrlen(val); 347 348 if (n == 0) return(str); 349 while (*str != 0) { /* non input consuming */ 350 if (*str == *val) { 351 if (!xmlStrncmp(str, val, n)) return((const xmlChar *) str); 352 } 353 str++; 354 } 355 return(NULL); 356 } 357 358 /** 359 * xmlStrcasestr: 360 * @str: the xmlChar * array (haystack) 361 * @val: the xmlChar to search (needle) 362 * 363 * a case-ignoring strstr for xmlChar's 364 * 365 * Returns the xmlChar * for the first occurrence or NULL. 366 */ 367 368 const xmlChar * 369 xmlStrcasestr(const xmlChar *str, const xmlChar *val) { 370 int n; 371 372 if (str == NULL) return(NULL); 373 if (val == NULL) return(NULL); 374 n = xmlStrlen(val); 375 376 if (n == 0) return(str); 377 while (*str != 0) { /* non input consuming */ 378 if (casemap[*str] == casemap[*val]) 379 if (!xmlStrncasecmp(str, val, n)) return(str); 380 str++; 381 } 382 return(NULL); 383 } 384 385 /** 386 * xmlStrsub: 387 * @str: the xmlChar * array (haystack) 388 * @start: the index of the first char (zero based) 389 * @len: the length of the substring 390 * 391 * Extract a substring of a given string 392 * 393 * Returns the xmlChar * for the first occurrence or NULL. 394 */ 395 396 xmlChar * 397 xmlStrsub(const xmlChar *str, int start, int len) { 398 int i; 399 400 if (str == NULL) return(NULL); 401 if (start < 0) return(NULL); 402 if (len < 0) return(NULL); 403 404 for (i = 0;i < start;i++) { 405 if (*str == 0) return(NULL); 406 str++; 407 } 408 if (*str == 0) return(NULL); 409 return(xmlStrndup(str, len)); 410 } 411 412 /** 413 * xmlStrlen: 414 * @str: the xmlChar * array 415 * 416 * length of a xmlChar's string 417 * 418 * Returns the number of xmlChar contained in the ARRAY. 419 */ 420 421 int 422 xmlStrlen(const xmlChar *str) { 423 int len = 0; 424 425 if (str == NULL) return(0); 426 while (*str != 0) { /* non input consuming */ 427 str++; 428 len++; 429 } 430 return(len); 431 } 432 433 /** 434 * xmlStrncat: 435 * @cur: the original xmlChar * array 436 * @add: the xmlChar * array added 437 * @len: the length of @add 438 * 439 * a strncat for array of xmlChar's, it will extend @cur with the len 440 * first bytes of @add. Note that if @len < 0 then this is an API error 441 * and NULL will be returned. 442 * 443 * Returns a new xmlChar *, the original @cur is reallocated if needed 444 * and should not be freed 445 */ 446 447 xmlChar * 448 xmlStrncat(xmlChar *cur, const xmlChar *add, int len) { 449 int size; 450 xmlChar *ret; 451 452 if ((add == NULL) || (len == 0)) 453 return(cur); 454 if (len < 0) 455 return(NULL); 456 if (cur == NULL) 457 return(xmlStrndup(add, len)); 458 459 size = xmlStrlen(cur); 460 ret = (xmlChar *) xmlRealloc(cur, (size + len + 1) * sizeof(xmlChar)); 461 if (ret == NULL) { 462 xmlErrMemory(NULL, NULL); 463 return(cur); 464 } 465 memcpy(&ret[size], add, len * sizeof(xmlChar)); 466 ret[size + len] = 0; 467 return(ret); 468 } 469 470 /** 471 * xmlStrncatNew: 472 * @str1: first xmlChar string 473 * @str2: second xmlChar string 474 * @len: the len of @str2 or < 0 475 * 476 * same as xmlStrncat, but creates a new string. The original 477 * two strings are not freed. If @len is < 0 then the length 478 * will be calculated automatically. 479 * 480 * Returns a new xmlChar * or NULL 481 */ 482 xmlChar * 483 xmlStrncatNew(const xmlChar *str1, const xmlChar *str2, int len) { 484 int size; 485 xmlChar *ret; 486 487 if (len < 0) 488 len = xmlStrlen(str2); 489 if ((str2 == NULL) || (len == 0)) 490 return(xmlStrdup(str1)); 491 if (str1 == NULL) 492 return(xmlStrndup(str2, len)); 493 494 size = xmlStrlen(str1); 495 ret = (xmlChar *) xmlMalloc((size + len + 1) * sizeof(xmlChar)); 496 if (ret == NULL) { 497 xmlErrMemory(NULL, NULL); 498 return(xmlStrndup(str1, size)); 499 } 500 memcpy(ret, str1, size * sizeof(xmlChar)); 501 memcpy(&ret[size], str2, len * sizeof(xmlChar)); 502 ret[size + len] = 0; 503 return(ret); 504 } 505 506 /** 507 * xmlStrcat: 508 * @cur: the original xmlChar * array 509 * @add: the xmlChar * array added 510 * 511 * a strcat for array of xmlChar's. Since they are supposed to be 512 * encoded in UTF-8 or an encoding with 8bit based chars, we assume 513 * a termination mark of '0'. 514 * 515 * Returns a new xmlChar * containing the concatenated string. 516 */ 517 xmlChar * 518 xmlStrcat(xmlChar *cur, const xmlChar *add) { 519 const xmlChar *p = add; 520 521 if (add == NULL) return(cur); 522 if (cur == NULL) 523 return(xmlStrdup(add)); 524 525 while (*p != 0) p++; /* non input consuming */ 526 return(xmlStrncat(cur, add, p - add)); 527 } 528 529 /** 530 * xmlStrPrintf: 531 * @buf: the result buffer. 532 * @len: the result buffer length. 533 * @msg: the message with printf formatting. 534 * @...: extra parameters for the message. 535 * 536 * Formats @msg and places result into @buf. 537 * 538 * Returns the number of characters written to @buf or -1 if an error occurs. 539 */ 540 int XMLCDECL 541 xmlStrPrintf(xmlChar *buf, int len, const xmlChar *msg, ...) { 542 va_list args; 543 int ret; 544 545 if((buf == NULL) || (msg == NULL)) { 546 return(-1); 547 } 548 549 va_start(args, msg); 550 ret = vsnprintf((char *) buf, len, (const char *) msg, args); 551 va_end(args); 552 buf[len - 1] = 0; /* be safe ! */ 553 554 return(ret); 555 } 556 557 /** 558 * xmlStrVPrintf: 559 * @buf: the result buffer. 560 * @len: the result buffer length. 561 * @msg: the message with printf formatting. 562 * @ap: extra parameters for the message. 563 * 564 * Formats @msg and places result into @buf. 565 * 566 * Returns the number of characters written to @buf or -1 if an error occurs. 567 */ 568 int 569 xmlStrVPrintf(xmlChar *buf, int len, const xmlChar *msg, va_list ap) { 570 int ret; 571 572 if((buf == NULL) || (msg == NULL)) { 573 return(-1); 574 } 575 576 ret = vsnprintf((char *) buf, len, (const char *) msg, ap); 577 buf[len - 1] = 0; /* be safe ! */ 578 579 return(ret); 580 } 581 582 /************************************************************************ 583 * * 584 * Generic UTF8 handling routines * 585 * * 586 * From rfc2044: encoding of the Unicode values on UTF-8: * 587 * * 588 * UCS-4 range (hex.) UTF-8 octet sequence (binary) * 589 * 0000 0000-0000 007F 0xxxxxxx * 590 * 0000 0080-0000 07FF 110xxxxx 10xxxxxx * 591 * 0000 0800-0000 FFFF 1110xxxx 10xxxxxx 10xxxxxx * 592 * * 593 * I hope we won't use values > 0xFFFF anytime soon ! * 594 * * 595 ************************************************************************/ 596 597 598 /** 599 * xmlUTF8Size: 600 * @utf: pointer to the UTF8 character 601 * 602 * calculates the internal size of a UTF8 character 603 * 604 * returns the numbers of bytes in the character, -1 on format error 605 */ 606 int 607 xmlUTF8Size(const xmlChar *utf) { 608 xmlChar mask; 609 int len; 610 611 if (utf == NULL) 612 return -1; 613 if (*utf < 0x80) 614 return 1; 615 /* check valid UTF8 character */ 616 if (!(*utf & 0x40)) 617 return -1; 618 /* determine number of bytes in char */ 619 len = 2; 620 for (mask=0x20; mask != 0; mask>>=1) { 621 if (!(*utf & mask)) 622 return len; 623 len++; 624 } 625 return -1; 626 } 627 628 /** 629 * xmlUTF8Charcmp: 630 * @utf1: pointer to first UTF8 char 631 * @utf2: pointer to second UTF8 char 632 * 633 * compares the two UCS4 values 634 * 635 * returns result of the compare as with xmlStrncmp 636 */ 637 int 638 xmlUTF8Charcmp(const xmlChar *utf1, const xmlChar *utf2) { 639 640 if (utf1 == NULL ) { 641 if (utf2 == NULL) 642 return 0; 643 return -1; 644 } 645 return xmlStrncmp(utf1, utf2, xmlUTF8Size(utf1)); 646 } 647 648 /** 649 * xmlUTF8Strlen: 650 * @utf: a sequence of UTF-8 encoded bytes 651 * 652 * compute the length of an UTF8 string, it doesn't do a full UTF8 653 * checking of the content of the string. 654 * 655 * Returns the number of characters in the string or -1 in case of error 656 */ 657 int 658 xmlUTF8Strlen(const xmlChar *utf) { 659 int ret = 0; 660 661 if (utf == NULL) 662 return(-1); 663 664 while (*utf != 0) { 665 if (utf[0] & 0x80) { 666 if ((utf[1] & 0xc0) != 0x80) 667 return(-1); 668 if ((utf[0] & 0xe0) == 0xe0) { 669 if ((utf[2] & 0xc0) != 0x80) 670 return(-1); 671 if ((utf[0] & 0xf0) == 0xf0) { 672 if ((utf[0] & 0xf8) != 0xf0 || (utf[3] & 0xc0) != 0x80) 673 return(-1); 674 utf += 4; 675 } else { 676 utf += 3; 677 } 678 } else { 679 utf += 2; 680 } 681 } else { 682 utf++; 683 } 684 ret++; 685 } 686 return(ret); 687 } 688 689 /** 690 * xmlGetUTF8Char: 691 * @utf: a sequence of UTF-8 encoded bytes 692 * @len: a pointer to the minimum number of bytes present in 693 * the sequence. This is used to assure the next character 694 * is completely contained within the sequence. 695 * 696 * Read the first UTF8 character from @utf 697 * 698 * Returns the char value or -1 in case of error, and sets *len to 699 * the actual number of bytes consumed (0 in case of error) 700 */ 701 int 702 xmlGetUTF8Char(const unsigned char *utf, int *len) { 703 unsigned int c; 704 705 if (utf == NULL) 706 goto error; 707 if (len == NULL) 708 goto error; 709 if (*len < 1) 710 goto error; 711 712 c = utf[0]; 713 if (c & 0x80) { 714 if (*len < 2) 715 goto error; 716 if ((utf[1] & 0xc0) != 0x80) 717 goto error; 718 if ((c & 0xe0) == 0xe0) { 719 if (*len < 3) 720 goto error; 721 if ((utf[2] & 0xc0) != 0x80) 722 goto error; 723 if ((c & 0xf0) == 0xf0) { 724 if (*len < 4) 725 goto error; 726 if ((c & 0xf8) != 0xf0 || (utf[3] & 0xc0) != 0x80) 727 goto error; 728 *len = 4; 729 /* 4-byte code */ 730 c = (utf[0] & 0x7) << 18; 731 c |= (utf[1] & 0x3f) << 12; 732 c |= (utf[2] & 0x3f) << 6; 733 c |= utf[3] & 0x3f; 734 } else { 735 /* 3-byte code */ 736 *len = 3; 737 c = (utf[0] & 0xf) << 12; 738 c |= (utf[1] & 0x3f) << 6; 739 c |= utf[2] & 0x3f; 740 } 741 } else { 742 /* 2-byte code */ 743 *len = 2; 744 c = (utf[0] & 0x1f) << 6; 745 c |= utf[1] & 0x3f; 746 } 747 } else { 748 /* 1-byte code */ 749 *len = 1; 750 } 751 return(c); 752 753 error: 754 if (len != NULL) 755 *len = 0; 756 return(-1); 757 } 758 759 /** 760 * xmlCheckUTF8: 761 * @utf: Pointer to putative UTF-8 encoded string. 762 * 763 * Checks @utf for being valid UTF-8. @utf is assumed to be 764 * null-terminated. This function is not super-strict, as it will 765 * allow longer UTF-8 sequences than necessary. Note that Java is 766 * capable of producing these sequences if provoked. Also note, this 767 * routine checks for the 4-byte maximum size, but does not check for 768 * 0x10ffff maximum value. 769 * 770 * Return value: true if @utf is valid. 771 **/ 772 int 773 xmlCheckUTF8(const unsigned char *utf) 774 { 775 int ix; 776 unsigned char c; 777 778 if (utf == NULL) 779 return(0); 780 /* 781 * utf is a string of 1, 2, 3 or 4 bytes. The valid strings 782 * are as follows (in "bit format"): 783 * 0xxxxxxx valid 1-byte 784 * 110xxxxx 10xxxxxx valid 2-byte 785 * 1110xxxx 10xxxxxx 10xxxxxx valid 3-byte 786 * 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx valid 4-byte 787 */ 788 for (ix = 0; (c = utf[ix]);) { /* string is 0-terminated */ 789 if ((c & 0x80) == 0x00) { /* 1-byte code, starts with 10 */ 790 ix++; 791 } else if ((c & 0xe0) == 0xc0) {/* 2-byte code, starts with 110 */ 792 if ((utf[ix+1] & 0xc0 ) != 0x80) 793 return 0; 794 ix += 2; 795 } else if ((c & 0xf0) == 0xe0) {/* 3-byte code, starts with 1110 */ 796 if (((utf[ix+1] & 0xc0) != 0x80) || 797 ((utf[ix+2] & 0xc0) != 0x80)) 798 return 0; 799 ix += 3; 800 } else if ((c & 0xf8) == 0xf0) {/* 4-byte code, starts with 11110 */ 801 if (((utf[ix+1] & 0xc0) != 0x80) || 802 ((utf[ix+2] & 0xc0) != 0x80) || 803 ((utf[ix+3] & 0xc0) != 0x80)) 804 return 0; 805 ix += 4; 806 } else /* unknown encoding */ 807 return 0; 808 } 809 return(1); 810 } 811 812 /** 813 * xmlUTF8Strsize: 814 * @utf: a sequence of UTF-8 encoded bytes 815 * @len: the number of characters in the array 816 * 817 * storage size of an UTF8 string 818 * the behaviour is not garanteed if the input string is not UTF-8 819 * 820 * Returns the storage size of 821 * the first 'len' characters of ARRAY 822 */ 823 824 int 825 xmlUTF8Strsize(const xmlChar *utf, int len) { 826 const xmlChar *ptr=utf; 827 xmlChar ch; 828 829 if (utf == NULL) 830 return(0); 831 832 if (len <= 0) 833 return(0); 834 835 while ( len-- > 0) { 836 if ( !*ptr ) 837 break; 838 if ( (ch = *ptr++) & 0x80) 839 while ((ch<<=1) & 0x80 ) { 840 ptr++; 841 if (*ptr == 0) break; 842 } 843 } 844 return (ptr - utf); 845 } 846 847 848 /** 849 * xmlUTF8Strndup: 850 * @utf: the input UTF8 * 851 * @len: the len of @utf (in chars) 852 * 853 * a strndup for array of UTF8's 854 * 855 * Returns a new UTF8 * or NULL 856 */ 857 xmlChar * 858 xmlUTF8Strndup(const xmlChar *utf, int len) { 859 xmlChar *ret; 860 int i; 861 862 if ((utf == NULL) || (len < 0)) return(NULL); 863 i = xmlUTF8Strsize(utf, len); 864 ret = (xmlChar *) xmlMallocAtomic((i + 1) * sizeof(xmlChar)); 865 if (ret == NULL) { 866 xmlGenericError(xmlGenericErrorContext, 867 "malloc of %ld byte failed\n", 868 (len + 1) * (long)sizeof(xmlChar)); 869 return(NULL); 870 } 871 memcpy(ret, utf, i * sizeof(xmlChar)); 872 ret[i] = 0; 873 return(ret); 874 } 875 876 /** 877 * xmlUTF8Strpos: 878 * @utf: the input UTF8 * 879 * @pos: the position of the desired UTF8 char (in chars) 880 * 881 * a function to provide the equivalent of fetching a 882 * character from a string array 883 * 884 * Returns a pointer to the UTF8 character or NULL 885 */ 886 const xmlChar * 887 xmlUTF8Strpos(const xmlChar *utf, int pos) { 888 xmlChar ch; 889 890 if (utf == NULL) return(NULL); 891 if (pos < 0) 892 return(NULL); 893 while (pos--) { 894 if ((ch=*utf++) == 0) return(NULL); 895 if ( ch & 0x80 ) { 896 /* if not simple ascii, verify proper format */ 897 if ( (ch & 0xc0) != 0xc0 ) 898 return(NULL); 899 /* then skip over remaining bytes for this char */ 900 while ( (ch <<= 1) & 0x80 ) 901 if ( (*utf++ & 0xc0) != 0x80 ) 902 return(NULL); 903 } 904 } 905 return((xmlChar *)utf); 906 } 907 908 /** 909 * xmlUTF8Strloc: 910 * @utf: the input UTF8 * 911 * @utfchar: the UTF8 character to be found 912 * 913 * a function to provide the relative location of a UTF8 char 914 * 915 * Returns the relative character position of the desired char 916 * or -1 if not found 917 */ 918 int 919 xmlUTF8Strloc(const xmlChar *utf, const xmlChar *utfchar) { 920 int i, size; 921 xmlChar ch; 922 923 if (utf==NULL || utfchar==NULL) return -1; 924 size = xmlUTF8Strsize(utfchar, 1); 925 for(i=0; (ch=*utf) != 0; i++) { 926 if (xmlStrncmp(utf, utfchar, size)==0) 927 return(i); 928 utf++; 929 if ( ch & 0x80 ) { 930 /* if not simple ascii, verify proper format */ 931 if ( (ch & 0xc0) != 0xc0 ) 932 return(-1); 933 /* then skip over remaining bytes for this char */ 934 while ( (ch <<= 1) & 0x80 ) 935 if ( (*utf++ & 0xc0) != 0x80 ) 936 return(-1); 937 } 938 } 939 940 return(-1); 941 } 942 /** 943 * xmlUTF8Strsub: 944 * @utf: a sequence of UTF-8 encoded bytes 945 * @start: relative pos of first char 946 * @len: total number to copy 947 * 948 * Create a substring from a given UTF-8 string 949 * Note: positions are given in units of UTF-8 chars 950 * 951 * Returns a pointer to a newly created string 952 * or NULL if any problem 953 */ 954 955 xmlChar * 956 xmlUTF8Strsub(const xmlChar *utf, int start, int len) { 957 int i; 958 xmlChar ch; 959 960 if (utf == NULL) return(NULL); 961 if (start < 0) return(NULL); 962 if (len < 0) return(NULL); 963 964 /* 965 * Skip over any leading chars 966 */ 967 for (i = 0;i < start;i++) { 968 if ((ch=*utf++) == 0) return(NULL); 969 if ( ch & 0x80 ) { 970 /* if not simple ascii, verify proper format */ 971 if ( (ch & 0xc0) != 0xc0 ) 972 return(NULL); 973 /* then skip over remaining bytes for this char */ 974 while ( (ch <<= 1) & 0x80 ) 975 if ( (*utf++ & 0xc0) != 0x80 ) 976 return(NULL); 977 } 978 } 979 980 return(xmlUTF8Strndup(utf, len)); 981 } 982 983 #define bottom_xmlstring 984 #include "elfgcchack.h" 985
