1 /* 2 * Copyright (C) 1984-2022 Mark Nudelman 3 * 4 * You may distribute under the terms of either the GNU General Public 5 * License or the Less License, as specified in the README file. 6 * 7 * For more information, see the README file. 8 */ 9 10 11 /* 12 * Functions to define the character set 13 * and do things specific to the character set. 14 */ 15 16 #include "less.h" 17 #if HAVE_LOCALE 18 #include <locale.h> 19 #include <ctype.h> 20 #include <langinfo.h> 21 #endif 22 23 #include "charset.h" 24 25 #if MSDOS_COMPILER==WIN32C 26 #define WIN32_LEAN_AND_MEAN 27 #include <windows.h> 28 #endif 29 30 extern int bs_mode; 31 32 public int utf_mode = 0; 33 34 /* 35 * Predefined character sets, 36 * selected by the LESSCHARSET environment variable. 37 */ 38 struct charset { 39 char *name; 40 int *p_flag; 41 char *desc; 42 } charsets[] = { 43 { "ascii", NULL, "8bcccbcc18b95.b" }, 44 { "utf-8", &utf_mode, "8bcccbcc18b95.b126.bb" }, 45 { "iso8859", NULL, "8bcccbcc18b95.33b." }, 46 { "latin3", NULL, "8bcccbcc18b95.33b5.b8.b15.b4.b12.b18.b12.b." }, 47 { "arabic", NULL, "8bcccbcc18b95.33b.3b.7b2.13b.3b.b26.5b19.b" }, 48 { "greek", NULL, "8bcccbcc18b95.33b4.2b4.b3.b35.b44.b" }, 49 { "greek2005", NULL, "8bcccbcc18b95.33b14.b35.b44.b" }, 50 { "hebrew", NULL, "8bcccbcc18b95.33b.b29.32b28.2b2.b" }, 51 { "koi8-r", NULL, "8bcccbcc18b95.b." }, 52 { "KOI8-T", NULL, "8bcccbcc18b95.b8.b6.b8.b.b.5b7.3b4.b4.b3.b.b.3b." }, 53 { "georgianps", NULL, "8bcccbcc18b95.3b11.4b12.2b." }, 54 { "tcvn", NULL, "b..b...bcccbccbbb7.8b95.b48.5b." }, 55 { "TIS-620", NULL, "8bcccbcc18b95.b.4b.11b7.8b." }, 56 { "next", NULL, "8bcccbcc18b95.bb125.bb" }, 57 { "dos", NULL, "8bcccbcc12bc5b95.b." }, 58 { "windows-1251", NULL, "8bcccbcc12bc5b95.b24.b." }, 59 { "windows-1252", NULL, "8bcccbcc12bc5b95.b.b11.b.2b12.b." }, 60 { "windows-1255", NULL, "8bcccbcc12bc5b95.b.b8.b.5b9.b.4b." }, 61 { "ebcdic", NULL, "5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b." }, 62 { "IBM-1047", NULL, "4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc191.b" }, 63 { NULL, NULL, NULL } 64 }; 65 66 /* 67 * Support "locale charmap"/nl_langinfo(CODESET) values, as well as others. 68 */ 69 struct cs_alias { 70 char *name; 71 char *oname; 72 } cs_aliases[] = { 73 { "UTF-8", "utf-8" }, 74 { "utf8", "utf-8" }, 75 { "UTF8", "utf-8" }, 76 { "ANSI_X3.4-1968", "ascii" }, 77 { "US-ASCII", "ascii" }, 78 { "latin1", "iso8859" }, 79 { "ISO-8859-1", "iso8859" }, 80 { "latin9", "iso8859" }, 81 { "ISO-8859-15", "iso8859" }, 82 { "latin2", "iso8859" }, 83 { "ISO-8859-2", "iso8859" }, 84 { "ISO-8859-3", "latin3" }, 85 { "latin4", "iso8859" }, 86 { "ISO-8859-4", "iso8859" }, 87 { "cyrillic", "iso8859" }, 88 { "ISO-8859-5", "iso8859" }, 89 { "ISO-8859-6", "arabic" }, 90 { "ISO-8859-7", "greek" }, 91 { "IBM9005", "greek2005" }, 92 { "ISO-8859-8", "hebrew" }, 93 { "latin5", "iso8859" }, 94 { "ISO-8859-9", "iso8859" }, 95 { "latin6", "iso8859" }, 96 { "ISO-8859-10", "iso8859" }, 97 { "latin7", "iso8859" }, 98 { "ISO-8859-13", "iso8859" }, 99 { "latin8", "iso8859" }, 100 { "ISO-8859-14", "iso8859" }, 101 { "latin10", "iso8859" }, 102 { "ISO-8859-16", "iso8859" }, 103 { "IBM437", "dos" }, 104 { "EBCDIC-US", "ebcdic" }, 105 { "IBM1047", "IBM-1047" }, 106 { "KOI8-R", "koi8-r" }, 107 { "KOI8-U", "koi8-r" }, 108 { "GEORGIAN-PS", "georgianps" }, 109 { "TCVN5712-1", "tcvn" }, 110 { "NEXTSTEP", "next" }, 111 { "windows", "windows-1252" }, /* backward compatibility */ 112 { "CP1251", "windows-1251" }, 113 { "CP1252", "windows-1252" }, 114 { "CP1255", "windows-1255" }, 115 { NULL, NULL } 116 }; 117 118 #define IS_BINARY_CHAR 01 119 #define IS_CONTROL_CHAR 02 120 121 static char chardef[256]; 122 static char *binfmt = NULL; 123 static char *utfbinfmt = NULL; 124 public int binattr = AT_STANDOUT|AT_COLOR_BIN; 125 126 127 /* 128 * Define a charset, given a description string. 129 * The string consists of 256 letters, 130 * one for each character in the charset. 131 * If the string is shorter than 256 letters, missing letters 132 * are taken to be identical to the last one. 133 * A decimal number followed by a letter is taken to be a 134 * repetition of the letter. 135 * 136 * Each letter is one of: 137 * . normal character 138 * b binary character 139 * c control character 140 */ 141 static void 142 ichardef(s) 143 char *s; 144 { 145 char *cp; 146 int n; 147 char v; 148 149 n = 0; 150 v = 0; 151 cp = chardef; 152 while (*s != '\0') 153 { 154 switch (*s++) 155 { 156 case '.': 157 v = 0; 158 break; 159 case 'c': 160 v = IS_CONTROL_CHAR; 161 break; 162 case 'b': 163 v = IS_BINARY_CHAR|IS_CONTROL_CHAR; 164 break; 165 166 case '0': case '1': case '2': case '3': case '4': 167 case '5': case '6': case '7': case '8': case '9': 168 n = (10 * n) + (s[-1] - '0'); 169 continue; 170 171 default: 172 error("invalid chardef", NULL_PARG); 173 quit(QUIT_ERROR); 174 /*NOTREACHED*/ 175 } 176 177 do 178 { 179 if (cp >= chardef + sizeof(chardef)) 180 { 181 error("chardef longer than 256", NULL_PARG); 182 quit(QUIT_ERROR); 183 /*NOTREACHED*/ 184 } 185 *cp++ = v; 186 } while (--n > 0); 187 n = 0; 188 } 189 190 while (cp < chardef + sizeof(chardef)) 191 *cp++ = v; 192 } 193 194 /* 195 * Define a charset, given a charset name. 196 * The valid charset names are listed in the "charsets" array. 197 */ 198 static int 199 icharset(name, no_error) 200 char *name; 201 int no_error; 202 { 203 struct charset *p; 204 struct cs_alias *a; 205 206 if (name == NULL || *name == '\0') 207 return (0); 208 209 /* First see if the name is an alias. */ 210 for (a = cs_aliases; a->name != NULL; a++) 211 { 212 if (strcmp(name, a->name) == 0) 213 { 214 name = a->oname; 215 break; 216 } 217 } 218 219 for (p = charsets; p->name != NULL; p++) 220 { 221 if (strcmp(name, p->name) == 0) 222 { 223 ichardef(p->desc); 224 if (p->p_flag != NULL) 225 { 226 #if MSDOS_COMPILER==WIN32C 227 *(p->p_flag) = 1 + (GetConsoleOutputCP() != CP_UTF8); 228 #else 229 *(p->p_flag) = 1; 230 #endif 231 } 232 return (1); 233 } 234 } 235 236 if (!no_error) { 237 error("invalid charset name", NULL_PARG); 238 quit(QUIT_ERROR); 239 } 240 return (0); 241 } 242 243 #if HAVE_LOCALE 244 /* 245 * Define a charset, given a locale name. 246 */ 247 static void 248 ilocale(VOID_PARAM) 249 { 250 int c; 251 252 for (c = 0; c < (int) sizeof(chardef); c++) 253 { 254 if (isprint(c)) 255 chardef[c] = 0; 256 else if (iscntrl(c)) 257 chardef[c] = IS_CONTROL_CHAR; 258 else 259 chardef[c] = IS_BINARY_CHAR|IS_CONTROL_CHAR; 260 } 261 } 262 #endif 263 264 /* 265 * Define the printing format for control (or binary utf) chars. 266 */ 267 public void 268 setfmt(s, fmtvarptr, attrptr, default_fmt) 269 char *s; 270 char **fmtvarptr; 271 int *attrptr; 272 char *default_fmt; 273 { 274 if (s && utf_mode) 275 { 276 /* It would be too hard to account for width otherwise. */ 277 char constant *t = s; 278 while (*t) 279 { 280 if (*t < ' ' || *t > '~') 281 { 282 s = default_fmt; 283 goto attr; 284 } 285 t++; 286 } 287 } 288 289 /* %n is evil */ 290 if (s == NULL || *s == '\0' || 291 (*s == '*' && (s[1] == '\0' || s[2] == '\0' || strchr(s + 2, 'n'))) || 292 (*s != '*' && strchr(s, 'n'))) 293 s = default_fmt; 294 295 /* 296 * Select the attributes if it starts with "*". 297 */ 298 attr: 299 if (*s == '*' && s[1] != '\0') 300 { 301 switch (s[1]) 302 { 303 case 'd': *attrptr = AT_BOLD; break; 304 case 'k': *attrptr = AT_BLINK; break; 305 case 's': *attrptr = AT_STANDOUT; break; 306 case 'u': *attrptr = AT_UNDERLINE; break; 307 default: *attrptr = AT_NORMAL; break; 308 } 309 s += 2; 310 } 311 *fmtvarptr = s; 312 } 313 314 /* 315 * 316 */ 317 static void 318 set_charset(VOID_PARAM) 319 { 320 char *s; 321 322 #if MSDOS_COMPILER==WIN32C 323 /* 324 * If the Windows console is using UTF-8, we'll use it too. 325 */ 326 if (GetConsoleOutputCP() == CP_UTF8) 327 if (icharset("utf-8", 1)) 328 return; 329 #endif 330 /* 331 * See if environment variable LESSCHARSET is defined. 332 */ 333 s = lgetenv("LESSCHARSET"); 334 if (icharset(s, 0)) 335 return; 336 337 /* 338 * LESSCHARSET is not defined: try LESSCHARDEF. 339 */ 340 s = lgetenv("LESSCHARDEF"); 341 if (!isnullenv(s)) 342 { 343 ichardef(s); 344 return; 345 } 346 347 #if HAVE_LOCALE 348 #ifdef CODESET 349 /* 350 * Try using the codeset name as the charset name. 351 */ 352 s = nl_langinfo(CODESET); 353 if (icharset(s, 1)) 354 return; 355 #endif 356 #endif 357 358 #if HAVE_STRSTR 359 /* 360 * Check whether LC_ALL, LC_CTYPE or LANG look like UTF-8 is used. 361 */ 362 if ((s = lgetenv("LC_ALL")) != NULL || 363 (s = lgetenv("LC_CTYPE")) != NULL || 364 (s = lgetenv("LANG")) != NULL) 365 { 366 if ( strstr(s, "UTF-8") != NULL || strstr(s, "utf-8") != NULL 367 || strstr(s, "UTF8") != NULL || strstr(s, "utf8") != NULL) 368 if (icharset("utf-8", 1)) 369 return; 370 } 371 #endif 372 373 #if HAVE_LOCALE 374 /* 375 * Get character definitions from locale functions, 376 * rather than from predefined charset entry. 377 */ 378 ilocale(); 379 #else 380 #if MSDOS_COMPILER 381 /* 382 * Default to "dos". 383 */ 384 (void) icharset("dos", 1); 385 #else 386 /* 387 * Default to "latin1". 388 */ 389 (void) icharset("latin1", 1); 390 #endif 391 #endif 392 } 393 394 /* 395 * Initialize charset data structures. 396 */ 397 public void 398 init_charset(VOID_PARAM) 399 { 400 char *s; 401 402 #if HAVE_LOCALE 403 setlocale(LC_ALL, ""); 404 #endif 405 406 set_charset(); 407 408 s = lgetenv("LESSBINFMT"); 409 setfmt(s, &binfmt, &binattr, "*s<%02X>"); 410 411 s = lgetenv("LESSUTFBINFMT"); 412 setfmt(s, &utfbinfmt, &binattr, "<U+%04lX>"); 413 } 414 415 /* 416 * Is a given character a "binary" character? 417 */ 418 public int 419 binary_char(c) 420 LWCHAR c; 421 { 422 if (utf_mode) 423 return (is_ubin_char(c)); 424 c &= 0377; 425 return (chardef[c] & IS_BINARY_CHAR); 426 } 427 428 /* 429 * Is a given character a "control" character? 430 */ 431 public int 432 control_char(c) 433 LWCHAR c; 434 { 435 c &= 0377; 436 return (chardef[c] & IS_CONTROL_CHAR); 437 } 438 439 /* 440 * Return the printable form of a character. 441 * For example, in the "ascii" charset '\3' is printed as "^C". 442 */ 443 public char * 444 prchar(c) 445 LWCHAR c; 446 { 447 /* {{ This buffer can be overrun if LESSBINFMT is a long string. }} */ 448 static char buf[MAX_PRCHAR_LEN+1]; 449 450 c &= 0377; 451 if ((c < 128 || !utf_mode) && !control_char(c)) 452 SNPRINTF1(buf, sizeof(buf), "%c", (int) c); 453 else if (c == ESC) 454 strcpy(buf, "ESC"); 455 #if IS_EBCDIC_HOST 456 else if (!binary_char(c) && c < 64) 457 SNPRINTF1(buf, sizeof(buf), "^%c", 458 /* 459 * This array roughly inverts CONTROL() #defined in less.h, 460 * and should be kept in sync with CONTROL() and IBM-1047. 461 */ 462 "@ABC.I.?...KLMNO" 463 "PQRS.JH.XY.." 464 "\\]^_" 465 "......W[.....EFG" 466 "..V....D....TU.Z"[c]); 467 #else 468 else if (c < 128 && !control_char(c ^ 0100)) 469 SNPRINTF1(buf, sizeof(buf), "^%c", (int) (c ^ 0100)); 470 #endif 471 else 472 SNPRINTF1(buf, sizeof(buf), binfmt, c); 473 return (buf); 474 } 475 476 /* 477 * Return the printable form of a UTF-8 character. 478 */ 479 public char * 480 prutfchar(ch) 481 LWCHAR ch; 482 { 483 static char buf[MAX_PRCHAR_LEN+1]; 484 485 if (ch == ESC) 486 strcpy(buf, "ESC"); 487 else if (ch < 128 && control_char(ch)) 488 { 489 if (!control_char(ch ^ 0100)) 490 SNPRINTF1(buf, sizeof(buf), "^%c", ((char) ch) ^ 0100); 491 else 492 SNPRINTF1(buf, sizeof(buf), binfmt, (char) ch); 493 } else if (is_ubin_char(ch)) 494 { 495 SNPRINTF1(buf, sizeof(buf), utfbinfmt, ch); 496 } else 497 { 498 char *p = buf; 499 if (ch >= 0x80000000) 500 ch = 0xFFFD; /* REPLACEMENT CHARACTER */ 501 put_wchar(&p, ch); 502 *p = '\0'; 503 } 504 return (buf); 505 } 506 507 /* 508 * Get the length of a UTF-8 character in bytes. 509 */ 510 public int 511 utf_len(ch) 512 int ch; 513 { 514 if ((ch & 0x80) == 0) 515 return 1; 516 if ((ch & 0xE0) == 0xC0) 517 return 2; 518 if ((ch & 0xF0) == 0xE0) 519 return 3; 520 if ((ch & 0xF8) == 0xF0) 521 return 4; 522 if ((ch & 0xFC) == 0xF8) 523 return 5; 524 if ((ch & 0xFE) == 0xFC) 525 return 6; 526 /* Invalid UTF-8 encoding. */ 527 return 1; 528 } 529 530 /* 531 * Does the parameter point to the lead byte of a well-formed UTF-8 character? 532 */ 533 public int 534 is_utf8_well_formed(ss, slen) 535 char *ss; 536 int slen; 537 { 538 int i; 539 int len; 540 unsigned char *s = (unsigned char *) ss; 541 542 if (IS_UTF8_INVALID(s[0])) 543 return (0); 544 545 len = utf_len(s[0]); 546 if (len > slen) 547 return (0); 548 if (len == 1) 549 return (1); 550 if (len == 2) 551 { 552 if (s[0] < 0xC2) 553 return (0); 554 } else 555 { 556 unsigned char mask; 557 mask = (~((1 << (8-len)) - 1)) & 0xFF; 558 if (s[0] == mask && (s[1] & mask) == 0x80) 559 return (0); 560 } 561 562 for (i = 1; i < len; i++) 563 if (!IS_UTF8_TRAIL(s[i])) 564 return (0); 565 return (1); 566 } 567 568 /* 569 * Skip bytes until a UTF-8 lead byte (11xxxxxx) or ASCII byte (0xxxxxxx) is found. 570 */ 571 public void 572 utf_skip_to_lead(pp, limit) 573 char **pp; 574 char *limit; 575 { 576 do { 577 ++(*pp); 578 } while (*pp < limit && !IS_UTF8_LEAD((*pp)[0] & 0377) && !IS_ASCII_OCTET((*pp)[0])); 579 } 580 581 582 /* 583 * Get the value of a UTF-8 character. 584 */ 585 public LWCHAR 586 get_wchar(p) 587 constant char *p; 588 { 589 switch (utf_len(p[0])) 590 { 591 case 1: 592 default: 593 /* 0xxxxxxx */ 594 return (LWCHAR) 595 (p[0] & 0xFF); 596 case 2: 597 /* 110xxxxx 10xxxxxx */ 598 return (LWCHAR) ( 599 ((p[0] & 0x1F) << 6) | 600 (p[1] & 0x3F)); 601 case 3: 602 /* 1110xxxx 10xxxxxx 10xxxxxx */ 603 return (LWCHAR) ( 604 ((p[0] & 0x0F) << 12) | 605 ((p[1] & 0x3F) << 6) | 606 (p[2] & 0x3F)); 607 case 4: 608 /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */ 609 return (LWCHAR) ( 610 ((p[0] & 0x07) << 18) | 611 ((p[1] & 0x3F) << 12) | 612 ((p[2] & 0x3F) << 6) | 613 (p[3] & 0x3F)); 614 case 5: 615 /* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 616 return (LWCHAR) ( 617 ((p[0] & 0x03) << 24) | 618 ((p[1] & 0x3F) << 18) | 619 ((p[2] & 0x3F) << 12) | 620 ((p[3] & 0x3F) << 6) | 621 (p[4] & 0x3F)); 622 case 6: 623 /* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 624 return (LWCHAR) ( 625 ((p[0] & 0x01) << 30) | 626 ((p[1] & 0x3F) << 24) | 627 ((p[2] & 0x3F) << 18) | 628 ((p[3] & 0x3F) << 12) | 629 ((p[4] & 0x3F) << 6) | 630 (p[5] & 0x3F)); 631 } 632 } 633 634 /* 635 * Store a character into a UTF-8 string. 636 */ 637 public void 638 put_wchar(pp, ch) 639 char **pp; 640 LWCHAR ch; 641 { 642 if (!utf_mode || ch < 0x80) 643 { 644 /* 0xxxxxxx */ 645 *(*pp)++ = (char) ch; 646 } else if (ch < 0x800) 647 { 648 /* 110xxxxx 10xxxxxx */ 649 *(*pp)++ = (char) (0xC0 | ((ch >> 6) & 0x1F)); 650 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 651 } else if (ch < 0x10000) 652 { 653 /* 1110xxxx 10xxxxxx 10xxxxxx */ 654 *(*pp)++ = (char) (0xE0 | ((ch >> 12) & 0x0F)); 655 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 656 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 657 } else if (ch < 0x200000) 658 { 659 /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */ 660 *(*pp)++ = (char) (0xF0 | ((ch >> 18) & 0x07)); 661 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F)); 662 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 663 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 664 } else if (ch < 0x4000000) 665 { 666 /* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 667 *(*pp)++ = (char) (0xF0 | ((ch >> 24) & 0x03)); 668 *(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F)); 669 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F)); 670 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 671 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 672 } else 673 { 674 /* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 675 *(*pp)++ = (char) (0xF0 | ((ch >> 30) & 0x01)); 676 *(*pp)++ = (char) (0x80 | ((ch >> 24) & 0x3F)); 677 *(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F)); 678 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F)); 679 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 680 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 681 } 682 } 683 684 /* 685 * Step forward or backward one character in a string. 686 */ 687 public LWCHAR 688 step_char(pp, dir, limit) 689 char **pp; 690 signed int dir; 691 constant char *limit; 692 { 693 LWCHAR ch; 694 int len; 695 char *p = *pp; 696 697 if (!utf_mode) 698 { 699 /* It's easy if chars are one byte. */ 700 if (dir > 0) 701 ch = (LWCHAR) (unsigned char) ((p < limit) ? *p++ : 0); 702 else 703 ch = (LWCHAR) (unsigned char) ((p > limit) ? *--p : 0); 704 } else if (dir > 0) 705 { 706 len = utf_len(*p); 707 if (p + len > limit) 708 { 709 ch = 0; 710 p = (char *) limit; 711 } else 712 { 713 ch = get_wchar(p); 714 p += len; 715 } 716 } else 717 { 718 while (p > limit && IS_UTF8_TRAIL(p[-1])) 719 p--; 720 if (p > limit) 721 ch = get_wchar(--p); 722 else 723 ch = 0; 724 } 725 *pp = p; 726 return ch; 727 } 728 729 /* 730 * Unicode characters data 731 * Actual data is in the generated *.uni files. 732 */ 733 734 #define DECLARE_RANGE_TABLE_START(name) \ 735 static struct wchar_range name##_array[] = { 736 #define DECLARE_RANGE_TABLE_END(name) \ 737 }; struct wchar_range_table name##_table = { name##_array, sizeof(name##_array)/sizeof(*name##_array) }; 738 739 DECLARE_RANGE_TABLE_START(compose) 740 #include "compose.uni" 741 DECLARE_RANGE_TABLE_END(compose) 742 743 DECLARE_RANGE_TABLE_START(ubin) 744 #include "ubin.uni" 745 DECLARE_RANGE_TABLE_END(ubin) 746 747 DECLARE_RANGE_TABLE_START(wide) 748 #include "wide.uni" 749 DECLARE_RANGE_TABLE_END(wide) 750 751 DECLARE_RANGE_TABLE_START(fmt) 752 #include "fmt.uni" 753 DECLARE_RANGE_TABLE_END(fmt) 754 755 /* comb_table is special pairs, not ranges. */ 756 static struct wchar_range comb_table[] = { 757 {0x0644,0x0622}, {0x0644,0x0623}, {0x0644,0x0625}, {0x0644,0x0627}, 758 }; 759 760 761 static int 762 is_in_table(ch, table) 763 LWCHAR ch; 764 struct wchar_range_table *table; 765 { 766 int hi; 767 int lo; 768 769 /* Binary search in the table. */ 770 if (ch < table->table[0].first) 771 return 0; 772 lo = 0; 773 hi = table->count - 1; 774 while (lo <= hi) 775 { 776 int mid = (lo + hi) / 2; 777 if (ch > table->table[mid].last) 778 lo = mid + 1; 779 else if (ch < table->table[mid].first) 780 hi = mid - 1; 781 else 782 return 1; 783 } 784 return 0; 785 } 786 787 /* 788 * Is a character a UTF-8 composing character? 789 * If a composing character follows any char, the two combine into one glyph. 790 */ 791 public int 792 is_composing_char(ch) 793 LWCHAR ch; 794 { 795 return is_in_table(ch, &compose_table) || 796 (bs_mode != BS_CONTROL && is_in_table(ch, &fmt_table)); 797 } 798 799 /* 800 * Should this UTF-8 character be treated as binary? 801 */ 802 public int 803 is_ubin_char(ch) 804 LWCHAR ch; 805 { 806 int ubin = is_in_table(ch, &ubin_table) || 807 (bs_mode == BS_CONTROL && is_in_table(ch, &fmt_table)); 808 return ubin; 809 } 810 811 /* 812 * Is this a double width UTF-8 character? 813 */ 814 public int 815 is_wide_char(ch) 816 LWCHAR ch; 817 { 818 return is_in_table(ch, &wide_table); 819 } 820 821 /* 822 * Is a character a UTF-8 combining character? 823 * A combining char acts like an ordinary char, but if it follows 824 * a specific char (not any char), the two combine into one glyph. 825 */ 826 public int 827 is_combining_char(ch1, ch2) 828 LWCHAR ch1; 829 LWCHAR ch2; 830 { 831 /* The table is small; use linear search. */ 832 int i; 833 for (i = 0; i < sizeof(comb_table)/sizeof(*comb_table); i++) 834 { 835 if (ch1 == comb_table[i].first && 836 ch2 == comb_table[i].last) 837 return 1; 838 } 839 return 0; 840 } 841 842