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 */
wchar_range_table_set(struct wchar_range_table * tbl,struct xbuffer * arr)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 */
skip_uprefix(char * s)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 */
wchar_range_get(char ** ss,struct wchar_range * range)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 */
ichardef_utf(char * s)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 */
ichardef(char * s)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 */
icharset(char * name,int no_error)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 */
ilocale(void)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 */
setfmt(char * s,char ** fmtvarptr,int * attrptr,char * default_fmt,int for_printf)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 */
set_charset(void)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 */
init_charset(void)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 */
binary_char(LWCHAR c)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 */
control_char(LWCHAR c)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 */
prchar(LWCHAR c)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 */
prutfchar(LWCHAR ch)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 */
utf_len(int ch)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 */
is_utf8_well_formed(char * ss,int slen)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 */
utf_skip_to_lead(char ** pp,char * limit)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 */
get_wchar(constant char * p)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 */
put_wchar(char ** pp,LWCHAR ch)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 */
step_char(char ** pp,signed int dir,constant char * limit)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
is_in_table(LWCHAR ch,struct wchar_range_table * table)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 */
is_composing_char(LWCHAR ch)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 */
is_ubin_char(LWCHAR ch)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 */
is_wide_char(LWCHAR ch)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 */
is_combining_char(LWCHAR ch1,LWCHAR ch2)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