1 /* 2 * Copyright (C) 1984-2023 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 #include "xbuf.h" 25 26 #if MSDOS_COMPILER==WIN32C 27 #define WIN32_LEAN_AND_MEAN 28 #include <windows.h> 29 #endif 30 31 extern int bs_mode; 32 33 public int utf_mode = 0; 34 35 /* 36 * Predefined character sets, 37 * selected by the LESSCHARSET environment variable. 38 */ 39 struct charset { 40 char *name; 41 int *p_flag; 42 char *desc; 43 } charsets[] = { 44 { "ascii", NULL, "8bcccbcc18b95.b" }, 45 { "utf-8", &utf_mode, "8bcccbcc18b95.b126.bb" }, 46 { "iso8859", NULL, "8bcccbcc18b95.33b." }, 47 { "latin3", NULL, "8bcccbcc18b95.33b5.b8.b15.b4.b12.b18.b12.b." }, 48 { "arabic", NULL, "8bcccbcc18b95.33b.3b.7b2.13b.3b.b26.5b19.b" }, 49 { "greek", NULL, "8bcccbcc18b95.33b4.2b4.b3.b35.b44.b" }, 50 { "greek2005", NULL, "8bcccbcc18b95.33b14.b35.b44.b" }, 51 { "hebrew", NULL, "8bcccbcc18b95.33b.b29.32b28.2b2.b" }, 52 { "koi8-r", NULL, "8bcccbcc18b95.b." }, 53 { "KOI8-T", NULL, "8bcccbcc18b95.b8.b6.b8.b.b.5b7.3b4.b4.b3.b.b.3b." }, 54 { "georgianps", NULL, "8bcccbcc18b95.3b11.4b12.2b." }, 55 { "tcvn", NULL, "b..b...bcccbccbbb7.8b95.b48.5b." }, 56 { "TIS-620", NULL, "8bcccbcc18b95.b.4b.11b7.8b." }, 57 { "next", NULL, "8bcccbcc18b95.bb125.bb" }, 58 { "dos", NULL, "8bcccbcc12bc5b95.b." }, 59 { "windows-1251", NULL, "8bcccbcc12bc5b95.b24.b." }, 60 { "windows-1252", NULL, "8bcccbcc12bc5b95.b.b11.b.2b12.b." }, 61 { "windows-1255", NULL, "8bcccbcc12bc5b95.b.b8.b.5b9.b.4b." }, 62 { "ebcdic", NULL, "5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b." }, 63 { "IBM-1047", NULL, "4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc191.b" }, 64 { NULL, NULL, NULL } 65 }; 66 67 /* 68 * Support "locale charmap"/nl_langinfo(CODESET) values, as well as others. 69 */ 70 struct cs_alias { 71 char *name; 72 char *oname; 73 } cs_aliases[] = { 74 { "UTF-8", "utf-8" }, 75 { "utf8", "utf-8" }, 76 { "UTF8", "utf-8" }, 77 { "ANSI_X3.4-1968", "ascii" }, 78 { "US-ASCII", "ascii" }, 79 { "latin1", "iso8859" }, 80 { "ISO-8859-1", "iso8859" }, 81 { "latin9", "iso8859" }, 82 { "ISO-8859-15", "iso8859" }, 83 { "latin2", "iso8859" }, 84 { "ISO-8859-2", "iso8859" }, 85 { "ISO-8859-3", "latin3" }, 86 { "latin4", "iso8859" }, 87 { "ISO-8859-4", "iso8859" }, 88 { "cyrillic", "iso8859" }, 89 { "ISO-8859-5", "iso8859" }, 90 { "ISO-8859-6", "arabic" }, 91 { "ISO-8859-7", "greek" }, 92 { "IBM9005", "greek2005" }, 93 { "ISO-8859-8", "hebrew" }, 94 { "latin5", "iso8859" }, 95 { "ISO-8859-9", "iso8859" }, 96 { "latin6", "iso8859" }, 97 { "ISO-8859-10", "iso8859" }, 98 { "latin7", "iso8859" }, 99 { "ISO-8859-13", "iso8859" }, 100 { "latin8", "iso8859" }, 101 { "ISO-8859-14", "iso8859" }, 102 { "latin10", "iso8859" }, 103 { "ISO-8859-16", "iso8859" }, 104 { "IBM437", "dos" }, 105 { "EBCDIC-US", "ebcdic" }, 106 { "IBM1047", "IBM-1047" }, 107 { "KOI8-R", "koi8-r" }, 108 { "KOI8-U", "koi8-r" }, 109 { "GEORGIAN-PS", "georgianps" }, 110 { "TCVN5712-1", "tcvn" }, 111 { "NEXTSTEP", "next" }, 112 { "windows", "windows-1252" }, /* backward compatibility */ 113 { "CP1251", "windows-1251" }, 114 { "CP1252", "windows-1252" }, 115 { "CP1255", "windows-1255" }, 116 { NULL, NULL } 117 }; 118 119 #define IS_BINARY_CHAR 01 120 #define IS_CONTROL_CHAR 02 121 122 static char chardef[256]; 123 static char *binfmt = NULL; 124 static char *utfbinfmt = NULL; 125 public int binattr = AT_STANDOUT|AT_COLOR_BIN; 126 127 static struct xbuffer user_wide_array; 128 static struct xbuffer user_ubin_array; 129 static struct xbuffer user_compose_array; 130 static struct xbuffer user_prt_array; 131 static struct wchar_range_table user_wide_table; 132 static struct wchar_range_table user_ubin_table; 133 static struct wchar_range_table user_compose_table; 134 static struct wchar_range_table user_prt_table; 135 136 /* 137 * Set a wchar_range_table to the table in an xbuffer. 138 */ 139 static void wchar_range_table_set(struct wchar_range_table *tbl, struct xbuffer *arr) 140 { 141 tbl->table = (struct wchar_range *) arr->data; 142 tbl->count = arr->end / sizeof(struct wchar_range); 143 } 144 145 /* 146 * Skip over a "U" or "U+" prefix before a hex codepoint. 147 */ 148 static char * skip_uprefix(char *s) 149 { 150 if (*s == 'U' || *s == 'u') 151 if (*++s == '+') ++s; 152 return s; 153 } 154 155 /* 156 * Parse a dash-separated range of hex values. 157 */ 158 static void wchar_range_get(char **ss, struct wchar_range *range) 159 { 160 char *s = skip_uprefix(*ss); 161 range->first = lstrtoul(s, &s, 16); 162 if (s[0] == '-') 163 { 164 s = skip_uprefix(&s[1]); 165 range->last = lstrtoul(s, &s, 16); 166 } else 167 { 168 range->last = range->first; 169 } 170 *ss = s; 171 } 172 173 /* 174 * Parse the LESSUTFCHARDEF variable. 175 */ 176 static void ichardef_utf(char *s) 177 { 178 xbuf_init(&user_wide_array); 179 xbuf_init(&user_ubin_array); 180 xbuf_init(&user_compose_array); 181 xbuf_init(&user_prt_array); 182 183 if (s != NULL) 184 { 185 while (s[0] != '\0') 186 { 187 struct wchar_range range; 188 wchar_range_get(&s, &range); 189 if (range.last == 0) 190 { 191 error("invalid hex number(s) in LESSUTFCHARDEF", NULL_PARG); 192 quit(QUIT_ERROR); 193 } 194 if (*s++ != ':') 195 { 196 error("missing colon in LESSUTFCHARDEF", NULL_PARG); 197 quit(QUIT_ERROR); 198 } 199 switch (*s++) 200 { 201 case 'b': 202 xbuf_add_data(&user_ubin_array, (unsigned char *) &range, sizeof(range)); 203 break; 204 case 'c': 205 xbuf_add_data(&user_compose_array, (unsigned char *) &range, sizeof(range)); 206 break; 207 case 'w': 208 xbuf_add_data(&user_wide_array, (unsigned char *) &range, sizeof(range)); 209 xbuf_add_data(&user_prt_array, (unsigned char *) &range, sizeof(range)); 210 break; 211 case 'p': case '.': 212 xbuf_add_data(&user_prt_array, (unsigned char *) &range, sizeof(range)); 213 break; 214 case '\0': 215 s--; 216 break; 217 default: 218 /* Ignore unknown character attribute. */ 219 break; 220 } 221 if (s[0] == ',') ++s; 222 } 223 } 224 wchar_range_table_set(&user_wide_table, &user_wide_array); 225 wchar_range_table_set(&user_ubin_table, &user_ubin_array); 226 wchar_range_table_set(&user_compose_table, &user_compose_array); 227 wchar_range_table_set(&user_prt_table, &user_prt_array); 228 } 229 230 /* 231 * Define a charset, given a description string. 232 * The string consists of 256 letters, 233 * one for each character in the charset. 234 * If the string is shorter than 256 letters, missing letters 235 * are taken to be identical to the last one. 236 * A decimal number followed by a letter is taken to be a 237 * repetition of the letter. 238 * 239 * Each letter is one of: 240 * . normal character 241 * b binary character 242 * c control character 243 */ 244 static void ichardef(char *s) 245 { 246 char *cp; 247 int n; 248 char v; 249 250 n = 0; 251 v = 0; 252 cp = chardef; 253 while (*s != '\0') 254 { 255 switch (*s++) 256 { 257 case '.': 258 v = 0; 259 break; 260 case 'c': 261 v = IS_CONTROL_CHAR; 262 break; 263 case 'b': 264 v = IS_BINARY_CHAR|IS_CONTROL_CHAR; 265 break; 266 267 case '0': case '1': case '2': case '3': case '4': 268 case '5': case '6': case '7': case '8': case '9': 269 if (ckd_mul(&n, n, 10) || ckd_add(&n, n, s[-1] - '0')) 270 goto invalid_chardef; 271 continue; 272 273 default: 274 invalid_chardef: 275 error("invalid chardef", NULL_PARG); 276 quit(QUIT_ERROR); 277 /*NOTREACHED*/ 278 } 279 280 do 281 { 282 if (cp >= chardef + sizeof(chardef)) 283 { 284 error("chardef longer than 256", NULL_PARG); 285 quit(QUIT_ERROR); 286 /*NOTREACHED*/ 287 } 288 *cp++ = v; 289 } while (--n > 0); 290 n = 0; 291 } 292 293 while (cp < chardef + sizeof(chardef)) 294 *cp++ = v; 295 } 296 297 /* 298 * Define a charset, given a charset name. 299 * The valid charset names are listed in the "charsets" array. 300 */ 301 static int icharset(char *name, int no_error) 302 { 303 struct charset *p; 304 struct cs_alias *a; 305 306 if (name == NULL || *name == '\0') 307 return (0); 308 309 /* First see if the name is an alias. */ 310 for (a = cs_aliases; a->name != NULL; a++) 311 { 312 if (strcmp(name, a->name) == 0) 313 { 314 name = a->oname; 315 break; 316 } 317 } 318 319 for (p = charsets; p->name != NULL; p++) 320 { 321 if (strcmp(name, p->name) == 0) 322 { 323 ichardef(p->desc); 324 if (p->p_flag != NULL) 325 { 326 #if MSDOS_COMPILER==WIN32C 327 *(p->p_flag) = 1 + (GetConsoleOutputCP() != CP_UTF8); 328 #else 329 *(p->p_flag) = 1; 330 #endif 331 } 332 return (1); 333 } 334 } 335 336 if (!no_error) { 337 error("invalid charset name", NULL_PARG); 338 quit(QUIT_ERROR); 339 } 340 return (0); 341 } 342 343 #if HAVE_LOCALE 344 /* 345 * Define a charset, given a locale name. 346 */ 347 static void ilocale(void) 348 { 349 int c; 350 351 for (c = 0; c < (int) sizeof(chardef); c++) 352 { 353 if (isprint(c)) 354 chardef[c] = 0; 355 else if (iscntrl(c)) 356 chardef[c] = IS_CONTROL_CHAR; 357 else 358 chardef[c] = IS_BINARY_CHAR|IS_CONTROL_CHAR; 359 } 360 } 361 #endif 362 363 /* 364 * Define the printing format for control (or binary utf) chars. 365 */ 366 public void setfmt(char *s, char **fmtvarptr, int *attrptr, char *default_fmt, int for_printf) 367 { 368 if (s && utf_mode) 369 { 370 /* It would be too hard to account for width otherwise. */ 371 char constant *t = s; 372 while (*t) 373 { 374 if (*t < ' ' || *t > '~') 375 { 376 s = default_fmt; 377 goto attr; 378 } 379 t++; 380 } 381 } 382 383 if (s == NULL || *s == '\0') 384 s = default_fmt; 385 else if (for_printf && 386 ((*s == '*' && (s[1] == '\0' || s[2] == '\0' || strchr(s + 2, 'n'))) || 387 (*s != '*' && strchr(s, 'n')))) 388 /* %n is evil */ 389 s = default_fmt; 390 391 /* 392 * Select the attributes if it starts with "*". 393 */ 394 attr: 395 if (*s == '*' && s[1] != '\0') 396 { 397 switch (s[1]) 398 { 399 case 'd': *attrptr = AT_BOLD; break; 400 case 'k': *attrptr = AT_BLINK; break; 401 case 's': *attrptr = AT_STANDOUT; break; 402 case 'u': *attrptr = AT_UNDERLINE; break; 403 default: *attrptr = AT_NORMAL; break; 404 } 405 s += 2; 406 } 407 *fmtvarptr = s; 408 } 409 410 /* 411 * 412 */ 413 static void set_charset(void) 414 { 415 char *s; 416 417 #if MSDOS_COMPILER==WIN32C 418 /* 419 * If the Windows console is using UTF-8, we'll use it too. 420 */ 421 if (GetConsoleOutputCP() == CP_UTF8) 422 if (icharset("utf-8", 1)) 423 return; 424 #endif 425 426 ichardef_utf(lgetenv("LESSUTFCHARDEF")); 427 428 /* 429 * See if environment variable LESSCHARSET is defined. 430 */ 431 s = lgetenv("LESSCHARSET"); 432 if (icharset(s, 0)) 433 return; 434 435 /* 436 * LESSCHARSET is not defined: try LESSCHARDEF. 437 */ 438 s = lgetenv("LESSCHARDEF"); 439 if (!isnullenv(s)) 440 { 441 ichardef(s); 442 return; 443 } 444 445 #if HAVE_LOCALE 446 #ifdef CODESET 447 /* 448 * Try using the codeset name as the charset name. 449 */ 450 s = nl_langinfo(CODESET); 451 if (icharset(s, 1)) 452 return; 453 #endif 454 #endif 455 456 #if HAVE_STRSTR 457 /* 458 * Check whether LC_ALL, LC_CTYPE or LANG look like UTF-8 is used. 459 */ 460 if ((s = lgetenv("LC_ALL")) != NULL || 461 (s = lgetenv("LC_CTYPE")) != NULL || 462 (s = lgetenv("LANG")) != NULL) 463 { 464 if ( strstr(s, "UTF-8") != NULL || strstr(s, "utf-8") != NULL 465 || strstr(s, "UTF8") != NULL || strstr(s, "utf8") != NULL) 466 if (icharset("utf-8", 1)) 467 return; 468 } 469 #endif 470 471 #if HAVE_LOCALE 472 /* 473 * Get character definitions from locale functions, 474 * rather than from predefined charset entry. 475 */ 476 ilocale(); 477 #else 478 #if MSDOS_COMPILER 479 /* 480 * Default to "dos". 481 */ 482 (void) icharset("dos", 1); 483 #else 484 /* 485 * Default to "latin1". 486 */ 487 (void) icharset("latin1", 1); 488 #endif 489 #endif 490 } 491 492 /* 493 * Initialize charset data structures. 494 */ 495 public void init_charset(void) 496 { 497 char *s; 498 499 #if HAVE_LOCALE 500 setlocale(LC_ALL, ""); 501 #endif 502 503 set_charset(); 504 505 s = lgetenv("LESSBINFMT"); 506 setfmt(s, &binfmt, &binattr, "*s<%02X>", TRUE); 507 508 s = lgetenv("LESSUTFBINFMT"); 509 setfmt(s, &utfbinfmt, &binattr, "<U+%04lX>", TRUE); 510 } 511 512 /* 513 * Is a given character a "binary" character? 514 */ 515 public int binary_char(LWCHAR c) 516 { 517 if (utf_mode) 518 return (is_ubin_char(c)); 519 c &= 0377; 520 return (chardef[c] & IS_BINARY_CHAR); 521 } 522 523 /* 524 * Is a given character a "control" character? 525 */ 526 public int control_char(LWCHAR c) 527 { 528 c &= 0377; 529 return (chardef[c] & IS_CONTROL_CHAR); 530 } 531 532 /* 533 * Return the printable form of a character. 534 * For example, in the "ascii" charset '\3' is printed as "^C". 535 */ 536 public char * prchar(LWCHAR c) 537 { 538 /* {{ This buffer can be overrun if LESSBINFMT is a long string. }} */ 539 static char buf[MAX_PRCHAR_LEN+1]; 540 541 c &= 0377; 542 if ((c < 128 || !utf_mode) && !control_char(c)) 543 SNPRINTF1(buf, sizeof(buf), "%c", (int) c); 544 else if (c == ESC) 545 strcpy(buf, "ESC"); 546 #if IS_EBCDIC_HOST 547 else if (!binary_char(c) && c < 64) 548 SNPRINTF1(buf, sizeof(buf), "^%c", 549 /* 550 * This array roughly inverts CONTROL() #defined in less.h, 551 * and should be kept in sync with CONTROL() and IBM-1047. 552 */ 553 "@ABC.I.?...KLMNO" 554 "PQRS.JH.XY.." 555 "\\]^_" 556 "......W[.....EFG" 557 "..V....D....TU.Z"[c]); 558 #else 559 else if (c < 128 && !control_char(c ^ 0100)) 560 SNPRINTF1(buf, sizeof(buf), "^%c", (int) (c ^ 0100)); 561 #endif 562 else 563 SNPRINTF1(buf, sizeof(buf), binfmt, c); 564 return (buf); 565 } 566 567 /* 568 * Return the printable form of a UTF-8 character. 569 */ 570 public char * prutfchar(LWCHAR ch) 571 { 572 static char buf[MAX_PRCHAR_LEN+1]; 573 574 if (ch == ESC) 575 strcpy(buf, "ESC"); 576 else if (ch < 128 && control_char(ch)) 577 { 578 if (!control_char(ch ^ 0100)) 579 SNPRINTF1(buf, sizeof(buf), "^%c", ((char) ch) ^ 0100); 580 else 581 SNPRINTF1(buf, sizeof(buf), binfmt, (char) ch); 582 } else if (is_ubin_char(ch)) 583 { 584 SNPRINTF1(buf, sizeof(buf), utfbinfmt, ch); 585 } else 586 { 587 char *p = buf; 588 if (ch >= 0x80000000) 589 ch = 0xFFFD; /* REPLACEMENT CHARACTER */ 590 put_wchar(&p, ch); 591 *p = '\0'; 592 } 593 return (buf); 594 } 595 596 /* 597 * Get the length of a UTF-8 character in bytes. 598 */ 599 public int utf_len(int ch) 600 { 601 if ((ch & 0x80) == 0) 602 return 1; 603 if ((ch & 0xE0) == 0xC0) 604 return 2; 605 if ((ch & 0xF0) == 0xE0) 606 return 3; 607 if ((ch & 0xF8) == 0xF0) 608 return 4; 609 if ((ch & 0xFC) == 0xF8) 610 return 5; 611 if ((ch & 0xFE) == 0xFC) 612 return 6; 613 /* Invalid UTF-8 encoding. */ 614 return 1; 615 } 616 617 /* 618 * Does the parameter point to the lead byte of a well-formed UTF-8 character? 619 */ 620 public int is_utf8_well_formed(char *ss, int slen) 621 { 622 int i; 623 int len; 624 unsigned char *s = (unsigned char *) ss; 625 626 if (IS_UTF8_INVALID(s[0])) 627 return (0); 628 629 len = utf_len(s[0]); 630 if (len > slen) 631 return (0); 632 if (len == 1) 633 return (1); 634 if (len == 2) 635 { 636 if (s[0] < 0xC2) 637 return (0); 638 } else 639 { 640 unsigned char mask; 641 mask = (~((1 << (8-len)) - 1)) & 0xFF; 642 if (s[0] == mask && (s[1] & mask) == 0x80) 643 return (0); 644 } 645 646 for (i = 1; i < len; i++) 647 if (!IS_UTF8_TRAIL(s[i])) 648 return (0); 649 return (1); 650 } 651 652 /* 653 * Skip bytes until a UTF-8 lead byte (11xxxxxx) or ASCII byte (0xxxxxxx) is found. 654 */ 655 public void utf_skip_to_lead(char **pp, char *limit) 656 { 657 do { 658 ++(*pp); 659 } while (*pp < limit && !IS_UTF8_LEAD((*pp)[0] & 0377) && !IS_ASCII_OCTET((*pp)[0])); 660 } 661 662 663 /* 664 * Get the value of a UTF-8 character. 665 */ 666 public LWCHAR get_wchar(constant char *p) 667 { 668 switch (utf_len(p[0])) 669 { 670 case 1: 671 default: 672 /* 0xxxxxxx */ 673 return (LWCHAR) 674 (p[0] & 0xFF); 675 case 2: 676 /* 110xxxxx 10xxxxxx */ 677 return (LWCHAR) ( 678 ((p[0] & 0x1F) << 6) | 679 (p[1] & 0x3F)); 680 case 3: 681 /* 1110xxxx 10xxxxxx 10xxxxxx */ 682 return (LWCHAR) ( 683 ((p[0] & 0x0F) << 12) | 684 ((p[1] & 0x3F) << 6) | 685 (p[2] & 0x3F)); 686 case 4: 687 /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */ 688 return (LWCHAR) ( 689 ((p[0] & 0x07) << 18) | 690 ((p[1] & 0x3F) << 12) | 691 ((p[2] & 0x3F) << 6) | 692 (p[3] & 0x3F)); 693 case 5: 694 /* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 695 return (LWCHAR) ( 696 ((p[0] & 0x03) << 24) | 697 ((p[1] & 0x3F) << 18) | 698 ((p[2] & 0x3F) << 12) | 699 ((p[3] & 0x3F) << 6) | 700 (p[4] & 0x3F)); 701 case 6: 702 /* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 703 return (LWCHAR) ( 704 ((p[0] & 0x01) << 30) | 705 ((p[1] & 0x3F) << 24) | 706 ((p[2] & 0x3F) << 18) | 707 ((p[3] & 0x3F) << 12) | 708 ((p[4] & 0x3F) << 6) | 709 (p[5] & 0x3F)); 710 } 711 } 712 713 /* 714 * Store a character into a UTF-8 string. 715 */ 716 public void put_wchar(char **pp, LWCHAR ch) 717 { 718 if (!utf_mode || ch < 0x80) 719 { 720 /* 0xxxxxxx */ 721 *(*pp)++ = (char) ch; 722 } else if (ch < 0x800) 723 { 724 /* 110xxxxx 10xxxxxx */ 725 *(*pp)++ = (char) (0xC0 | ((ch >> 6) & 0x1F)); 726 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 727 } else if (ch < 0x10000) 728 { 729 /* 1110xxxx 10xxxxxx 10xxxxxx */ 730 *(*pp)++ = (char) (0xE0 | ((ch >> 12) & 0x0F)); 731 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 732 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 733 } else if (ch < 0x200000) 734 { 735 /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */ 736 *(*pp)++ = (char) (0xF0 | ((ch >> 18) & 0x07)); 737 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F)); 738 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 739 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 740 } else if (ch < 0x4000000) 741 { 742 /* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 743 *(*pp)++ = (char) (0xF0 | ((ch >> 24) & 0x03)); 744 *(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F)); 745 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F)); 746 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 747 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 748 } else 749 { 750 /* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */ 751 *(*pp)++ = (char) (0xF0 | ((ch >> 30) & 0x01)); 752 *(*pp)++ = (char) (0x80 | ((ch >> 24) & 0x3F)); 753 *(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F)); 754 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F)); 755 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F)); 756 *(*pp)++ = (char) (0x80 | (ch & 0x3F)); 757 } 758 } 759 760 /* 761 * Step forward or backward one character in a string. 762 */ 763 public LWCHAR step_char(char **pp, signed int dir, constant char *limit) 764 { 765 LWCHAR ch; 766 int len; 767 char *p = *pp; 768 769 if (!utf_mode) 770 { 771 /* It's easy if chars are one byte. */ 772 if (dir > 0) 773 ch = (LWCHAR) (unsigned char) ((p < limit) ? *p++ : 0); 774 else 775 ch = (LWCHAR) (unsigned char) ((p > limit) ? *--p : 0); 776 } else if (dir > 0) 777 { 778 len = utf_len(*p); 779 if (p + len > limit) 780 { 781 ch = 0; 782 p = (char *) limit; 783 } else 784 { 785 ch = get_wchar(p); 786 p += len; 787 } 788 } else 789 { 790 while (p > limit && IS_UTF8_TRAIL(p[-1])) 791 p--; 792 if (p > limit) 793 ch = get_wchar(--p); 794 else 795 ch = 0; 796 } 797 *pp = p; 798 return ch; 799 } 800 801 /* 802 * Unicode characters data 803 * Actual data is in the generated *.uni files. 804 */ 805 806 #define DECLARE_RANGE_TABLE_START(name) \ 807 static struct wchar_range name##_array[] = { 808 #define DECLARE_RANGE_TABLE_END(name) \ 809 }; struct wchar_range_table name##_table = { name##_array, sizeof(name##_array)/sizeof(*name##_array) }; 810 811 DECLARE_RANGE_TABLE_START(compose) 812 #include "compose.uni" 813 DECLARE_RANGE_TABLE_END(compose) 814 815 DECLARE_RANGE_TABLE_START(ubin) 816 #include "ubin.uni" 817 DECLARE_RANGE_TABLE_END(ubin) 818 819 DECLARE_RANGE_TABLE_START(wide) 820 #include "wide.uni" 821 DECLARE_RANGE_TABLE_END(wide) 822 823 DECLARE_RANGE_TABLE_START(fmt) 824 #include "fmt.uni" 825 DECLARE_RANGE_TABLE_END(fmt) 826 827 /* comb_table is special pairs, not ranges. */ 828 static struct wchar_range comb_table[] = { 829 {0x0644,0x0622}, {0x0644,0x0623}, {0x0644,0x0625}, {0x0644,0x0627}, 830 }; 831 832 833 static int is_in_table(LWCHAR ch, struct wchar_range_table *table) 834 { 835 int hi; 836 int lo; 837 838 /* Binary search in the table. */ 839 if (table->table == NULL || table->count == 0 || ch < table->table[0].first) 840 return 0; 841 lo = 0; 842 hi = table->count - 1; 843 while (lo <= hi) 844 { 845 int mid = (lo + hi) / 2; 846 if (ch > table->table[mid].last) 847 lo = mid + 1; 848 else if (ch < table->table[mid].first) 849 hi = mid - 1; 850 else 851 return 1; 852 } 853 return 0; 854 } 855 856 /* 857 * Is a character a UTF-8 composing character? 858 * If a composing character follows any char, the two combine into one glyph. 859 */ 860 public int is_composing_char(LWCHAR ch) 861 { 862 if (is_in_table(ch, &user_prt_table)) return 0; 863 return is_in_table(ch, &user_compose_table) || 864 is_in_table(ch, &compose_table) || 865 (bs_mode != BS_CONTROL && is_in_table(ch, &fmt_table)); 866 } 867 868 /* 869 * Should this UTF-8 character be treated as binary? 870 */ 871 public int is_ubin_char(LWCHAR ch) 872 { 873 if (is_in_table(ch, &user_prt_table)) return 0; 874 return is_in_table(ch, &user_ubin_table) || 875 is_in_table(ch, &ubin_table) || 876 (bs_mode == BS_CONTROL && is_in_table(ch, &fmt_table)); 877 } 878 879 /* 880 * Is this a double width UTF-8 character? 881 */ 882 public int is_wide_char(LWCHAR ch) 883 { 884 return is_in_table(ch, &user_wide_table) || 885 is_in_table(ch, &wide_table); 886 } 887 888 /* 889 * Is a character a UTF-8 combining character? 890 * A combining char acts like an ordinary char, but if it follows 891 * a specific char (not any char), the two combine into one glyph. 892 */ 893 public int is_combining_char(LWCHAR ch1, LWCHAR ch2) 894 { 895 /* The table is small; use linear search. */ 896 int i; 897 for (i = 0; i < sizeof(comb_table)/sizeof(*comb_table); i++) 898 { 899 if (ch1 == comb_table[i].first && 900 ch2 == comb_table[i].last) 901 return 1; 902 } 903 return 0; 904 } 905 906