1 /* $NetBSD: charset.c,v 1.5 2023/10/06 05:49:49 simonb Exp $ */
2
3 /*
4 * Copyright (C) 1984-2023 Mark Nudelman
5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Less License, as specified in the README file.
8 *
9 * For more information, see the README file.
10 */
11
12
13 /*
14 * Functions to define the character set
15 * and do things specific to the character set.
16 */
17
18 #include "less.h"
19 #if HAVE_LOCALE
20 #include <locale.h>
21 #include <ctype.h>
22 #include <langinfo.h>
23 #endif
24
25 #include "charset.h"
26 #include "xbuf.h"
27
28 #if MSDOS_COMPILER==WIN32C
29 #define WIN32_LEAN_AND_MEAN
30 #include <windows.h>
31 #endif
32
33 extern int bs_mode;
34
35 public int utf_mode = 0;
36
37 /*
38 * Predefined character sets,
39 * selected by the LESSCHARSET environment variable.
40 */
41 struct charset {
42 char *name;
43 int *p_flag;
44 char *desc;
45 } charsets[] = {
46 { "ascii", NULL, "8bcccbcc18b95.b" },
47 { "utf-8", &utf_mode, "8bcccbcc18b95.b126.bb" },
48 { "iso8859", NULL, "8bcccbcc18b95.33b." },
49 { "latin3", NULL, "8bcccbcc18b95.33b5.b8.b15.b4.b12.b18.b12.b." },
50 { "arabic", NULL, "8bcccbcc18b95.33b.3b.7b2.13b.3b.b26.5b19.b" },
51 { "greek", NULL, "8bcccbcc18b95.33b4.2b4.b3.b35.b44.b" },
52 { "greek2005", NULL, "8bcccbcc18b95.33b14.b35.b44.b" },
53 { "hebrew", NULL, "8bcccbcc18b95.33b.b29.32b28.2b2.b" },
54 { "koi8-r", NULL, "8bcccbcc18b95.b." },
55 { "KOI8-T", NULL, "8bcccbcc18b95.b8.b6.b8.b.b.5b7.3b4.b4.b3.b.b.3b." },
56 { "georgianps", NULL, "8bcccbcc18b95.3b11.4b12.2b." },
57 { "tcvn", NULL, "b..b...bcccbccbbb7.8b95.b48.5b." },
58 { "TIS-620", NULL, "8bcccbcc18b95.b.4b.11b7.8b." },
59 { "next", NULL, "8bcccbcc18b95.bb125.bb" },
60 { "dos", NULL, "8bcccbcc12bc5b95.b." },
61 { "windows-1251", NULL, "8bcccbcc12bc5b95.b24.b." },
62 { "windows-1252", NULL, "8bcccbcc12bc5b95.b.b11.b.2b12.b." },
63 { "windows-1255", NULL, "8bcccbcc12bc5b95.b.b8.b.5b9.b.4b." },
64 { "ebcdic", NULL, "5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b." },
65 { "IBM-1047", NULL, "4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc191.b" },
66 { NULL, NULL, NULL }
67 };
68
69 /*
70 * Support "locale charmap"/nl_langinfo(CODESET) values, as well as others.
71 */
72 struct cs_alias {
73 char *name;
74 char *oname;
75 } cs_aliases[] = {
76 { "UTF-8", "utf-8" },
77 { "utf8", "utf-8" },
78 { "UTF8", "utf-8" },
79 { "ANSI_X3.4-1968", "ascii" },
80 { "US-ASCII", "ascii" },
81 { "latin1", "iso8859" },
82 { "ISO-8859-1", "iso8859" },
83 { "latin9", "iso8859" },
84 { "ISO-8859-15", "iso8859" },
85 { "latin2", "iso8859" },
86 { "ISO-8859-2", "iso8859" },
87 { "ISO-8859-3", "latin3" },
88 { "latin4", "iso8859" },
89 { "ISO-8859-4", "iso8859" },
90 { "cyrillic", "iso8859" },
91 { "ISO-8859-5", "iso8859" },
92 { "ISO-8859-6", "arabic" },
93 { "ISO-8859-7", "greek" },
94 { "IBM9005", "greek2005" },
95 { "ISO-8859-8", "hebrew" },
96 { "latin5", "iso8859" },
97 { "ISO-8859-9", "iso8859" },
98 { "latin6", "iso8859" },
99 { "ISO-8859-10", "iso8859" },
100 { "latin7", "iso8859" },
101 { "ISO-8859-13", "iso8859" },
102 { "latin8", "iso8859" },
103 { "ISO-8859-14", "iso8859" },
104 { "latin10", "iso8859" },
105 { "ISO-8859-16", "iso8859" },
106 { "IBM437", "dos" },
107 { "EBCDIC-US", "ebcdic" },
108 { "IBM1047", "IBM-1047" },
109 { "KOI8-R", "koi8-r" },
110 { "KOI8-U", "koi8-r" },
111 { "GEORGIAN-PS", "georgianps" },
112 { "TCVN5712-1", "tcvn" },
113 { "NEXTSTEP", "next" },
114 { "windows", "windows-1252" }, /* backward compatibility */
115 { "CP1251", "windows-1251" },
116 { "CP1252", "windows-1252" },
117 { "CP1255", "windows-1255" },
118 { NULL, NULL }
119 };
120
121 #define IS_BINARY_CHAR 01
122 #define IS_CONTROL_CHAR 02
123
124 static char chardef[256];
125 static char *binfmt = NULL;
126 static char *utfbinfmt = NULL;
127 public int binattr = AT_STANDOUT|AT_COLOR_BIN;
128
129 static struct xbuffer user_wide_array;
130 static struct xbuffer user_ubin_array;
131 static struct xbuffer user_compose_array;
132 static struct xbuffer user_prt_array;
133 static struct wchar_range_table user_wide_table;
134 static struct wchar_range_table user_ubin_table;
135 static struct wchar_range_table user_compose_table;
136 static struct wchar_range_table user_prt_table;
137
138 /*
139 * Set a wchar_range_table to the table in an xbuffer.
140 */
wchar_range_table_set(struct wchar_range_table * tbl,struct xbuffer * arr)141 static void wchar_range_table_set(struct wchar_range_table *tbl, struct xbuffer *arr)
142 {
143 tbl->table = (struct wchar_range *) arr->data;
144 tbl->count = arr->end / sizeof(struct wchar_range);
145 }
146
147 /*
148 * Skip over a "U" or "U+" prefix before a hex codepoint.
149 */
skip_uprefix(char * s)150 static char * skip_uprefix(char *s)
151 {
152 if (*s == 'U' || *s == 'u')
153 if (*++s == '+') ++s;
154 return s;
155 }
156
157 /*
158 * Parse a dash-separated range of hex values.
159 */
wchar_range_get(char ** ss,struct wchar_range * range)160 static void wchar_range_get(char **ss, struct wchar_range *range)
161 {
162 char *s = skip_uprefix(*ss);
163 range->first = lstrtoul(s, &s, 16);
164 if (s[0] == '-')
165 {
166 s = skip_uprefix(&s[1]);
167 range->last = lstrtoul(s, &s, 16);
168 } else
169 {
170 range->last = range->first;
171 }
172 *ss = s;
173 }
174
175 /*
176 * Parse the LESSUTFCHARDEF variable.
177 */
ichardef_utf(char * s)178 static void ichardef_utf(char *s)
179 {
180 xbuf_init(&user_wide_array);
181 xbuf_init(&user_ubin_array);
182 xbuf_init(&user_compose_array);
183 xbuf_init(&user_prt_array);
184
185 if (s != NULL)
186 {
187 while (s[0] != '\0')
188 {
189 struct wchar_range range;
190 wchar_range_get(&s, &range);
191 if (range.last == 0)
192 {
193 error("invalid hex number(s) in LESSUTFCHARDEF", NULL_PARG);
194 quit(QUIT_ERROR);
195 }
196 if (*s++ != ':')
197 {
198 error("missing colon in LESSUTFCHARDEF", NULL_PARG);
199 quit(QUIT_ERROR);
200 }
201 switch (*s++)
202 {
203 case 'b':
204 xbuf_add_data(&user_ubin_array, (unsigned char *) &range, sizeof(range));
205 break;
206 case 'c':
207 xbuf_add_data(&user_compose_array, (unsigned char *) &range, sizeof(range));
208 break;
209 case 'w':
210 xbuf_add_data(&user_wide_array, (unsigned char *) &range, sizeof(range));
211 xbuf_add_data(&user_prt_array, (unsigned char *) &range, sizeof(range));
212 break;
213 case 'p': case '.':
214 xbuf_add_data(&user_prt_array, (unsigned char *) &range, sizeof(range));
215 break;
216 case '\0':
217 s--;
218 break;
219 default:
220 /* Ignore unknown character attribute. */
221 break;
222 }
223 if (s[0] == ',') ++s;
224 }
225 }
226 wchar_range_table_set(&user_wide_table, &user_wide_array);
227 wchar_range_table_set(&user_ubin_table, &user_ubin_array);
228 wchar_range_table_set(&user_compose_table, &user_compose_array);
229 wchar_range_table_set(&user_prt_table, &user_prt_array);
230 }
231
232 /*
233 * Define a charset, given a description string.
234 * The string consists of 256 letters,
235 * one for each character in the charset.
236 * If the string is shorter than 256 letters, missing letters
237 * are taken to be identical to the last one.
238 * A decimal number followed by a letter is taken to be a
239 * repetition of the letter.
240 *
241 * Each letter is one of:
242 * . normal character
243 * b binary character
244 * c control character
245 */
ichardef(char * s)246 static void ichardef(char *s)
247 {
248 char *cp;
249 int n;
250 char v;
251
252 n = 0;
253 v = 0;
254 cp = chardef;
255 while (*s != '\0')
256 {
257 switch (*s++)
258 {
259 case '.':
260 v = 0;
261 break;
262 case 'c':
263 v = IS_CONTROL_CHAR;
264 break;
265 case 'b':
266 v = IS_BINARY_CHAR|IS_CONTROL_CHAR;
267 break;
268
269 case '0': case '1': case '2': case '3': case '4':
270 case '5': case '6': case '7': case '8': case '9':
271 if (ckd_mul(&n, n, 10) || ckd_add(&n, n, s[-1] - '0'))
272 goto invalid_chardef;
273 continue;
274
275 default:
276 invalid_chardef:
277 error("invalid chardef", NULL_PARG);
278 quit(QUIT_ERROR);
279 /*NOTREACHED*/
280 }
281
282 do
283 {
284 if (cp >= chardef + sizeof(chardef))
285 {
286 error("chardef longer than 256", NULL_PARG);
287 quit(QUIT_ERROR);
288 /*NOTREACHED*/
289 }
290 *cp++ = v;
291 } while (--n > 0);
292 n = 0;
293 }
294
295 while (cp < chardef + sizeof(chardef))
296 *cp++ = v;
297 }
298
299 /*
300 * Define a charset, given a charset name.
301 * The valid charset names are listed in the "charsets" array.
302 */
icharset(char * name,int no_error)303 static int icharset(char *name, int no_error)
304 {
305 struct charset *p;
306 struct cs_alias *a;
307
308 if (name == NULL || *name == '\0')
309 return (0);
310
311 /* First see if the name is an alias. */
312 for (a = cs_aliases; a->name != NULL; a++)
313 {
314 if (strcmp(name, a->name) == 0)
315 {
316 name = a->oname;
317 break;
318 }
319 }
320
321 for (p = charsets; p->name != NULL; p++)
322 {
323 if (strcmp(name, p->name) == 0)
324 {
325 ichardef(p->desc);
326 if (p->p_flag != NULL)
327 {
328 #if MSDOS_COMPILER==WIN32C
329 *(p->p_flag) = 1 + (GetConsoleOutputCP() != CP_UTF8);
330 #else
331 *(p->p_flag) = 1;
332 #endif
333 }
334 return (1);
335 }
336 }
337
338 if (!no_error) {
339 error("invalid charset name", NULL_PARG);
340 quit(QUIT_ERROR);
341 }
342 return (0);
343 }
344
345 #if HAVE_LOCALE
346 /*
347 * Define a charset, given a locale name.
348 */
ilocale(void)349 static void ilocale(void)
350 {
351 int c;
352
353 for (c = 0; c < (int) sizeof(chardef); c++)
354 {
355 if (isprint(c))
356 chardef[c] = 0;
357 else if (iscntrl(c))
358 chardef[c] = IS_CONTROL_CHAR;
359 else
360 chardef[c] = IS_BINARY_CHAR|IS_CONTROL_CHAR;
361 }
362 }
363 #endif
364
365 /*
366 * Define the printing format for control (or binary utf) chars.
367 */
setfmt(char * s,char ** fmtvarptr,int * attrptr,char * default_fmt,int for_printf)368 public void setfmt(char *s, char **fmtvarptr, int *attrptr, char *default_fmt, int for_printf)
369 {
370 if (s && utf_mode)
371 {
372 /* It would be too hard to account for width otherwise. */
373 char constant *t = s;
374 while (*t)
375 {
376 if (*t < ' ' || *t > '~')
377 {
378 s = default_fmt;
379 goto attr;
380 }
381 t++;
382 }
383 }
384
385 if (s == NULL || *s == '\0')
386 s = default_fmt;
387 else if (for_printf &&
388 ((*s == '*' && (s[1] == '\0' || s[2] == '\0' || strchr(s + 2, 'n'))) ||
389 (*s != '*' && strchr(s, 'n'))))
390 /* %n is evil */
391 s = default_fmt;
392
393 /*
394 * Select the attributes if it starts with "*".
395 */
396 attr:
397 if (*s == '*' && s[1] != '\0')
398 {
399 switch (s[1])
400 {
401 case 'd': *attrptr = AT_BOLD; break;
402 case 'k': *attrptr = AT_BLINK; break;
403 case 's': *attrptr = AT_STANDOUT; break;
404 case 'u': *attrptr = AT_UNDERLINE; break;
405 default: *attrptr = AT_NORMAL; break;
406 }
407 s += 2;
408 }
409 *fmtvarptr = s;
410 }
411
412 /*
413 *
414 */
set_charset(void)415 static void set_charset(void)
416 {
417 char *s;
418
419 #if MSDOS_COMPILER==WIN32C
420 /*
421 * If the Windows console is using UTF-8, we'll use it too.
422 */
423 if (GetConsoleOutputCP() == CP_UTF8)
424 if (icharset("utf-8", 1))
425 return;
426 #endif
427
428 ichardef_utf(lgetenv("LESSUTFCHARDEF"));
429
430 /*
431 * See if environment variable LESSCHARSET is defined.
432 */
433 s = lgetenv("LESSCHARSET");
434 if (icharset(s, 0))
435 return;
436
437 /*
438 * LESSCHARSET is not defined: try LESSCHARDEF.
439 */
440 s = lgetenv("LESSCHARDEF");
441 if (!isnullenv(s))
442 {
443 ichardef(s);
444 return;
445 }
446
447 #if HAVE_LOCALE
448 #ifdef CODESET
449 /*
450 * Try using the codeset name as the charset name.
451 */
452 s = nl_langinfo(CODESET);
453 if (icharset(s, 1))
454 return;
455 #endif
456 #endif
457
458 #if HAVE_STRSTR
459 /*
460 * Check whether LC_ALL, LC_CTYPE or LANG look like UTF-8 is used.
461 */
462 if ((s = lgetenv("LC_ALL")) != NULL ||
463 (s = lgetenv("LC_CTYPE")) != NULL ||
464 (s = lgetenv("LANG")) != NULL)
465 {
466 if ( strstr(s, "UTF-8") != NULL || strstr(s, "utf-8") != NULL
467 || strstr(s, "UTF8") != NULL || strstr(s, "utf8") != NULL)
468 if (icharset("utf-8", 1))
469 return;
470 }
471 #endif
472
473 #if HAVE_LOCALE
474 /*
475 * Get character definitions from locale functions,
476 * rather than from predefined charset entry.
477 */
478 ilocale();
479 #else
480 #if MSDOS_COMPILER
481 /*
482 * Default to "dos".
483 */
484 (void) icharset("dos", 1);
485 #else
486 /*
487 * Default to "latin1".
488 */
489 (void) icharset("latin1", 1);
490 #endif
491 #endif
492 }
493
494 /*
495 * Initialize charset data structures.
496 */
init_charset(void)497 public void init_charset(void)
498 {
499 char *s;
500
501 #if HAVE_LOCALE
502 setlocale(LC_ALL, "");
503 #endif
504
505 set_charset();
506
507 s = lgetenv("LESSBINFMT");
508 setfmt(s, &binfmt, &binattr, "*s<%02X>", TRUE);
509
510 s = lgetenv("LESSUTFBINFMT");
511 setfmt(s, &utfbinfmt, &binattr, "<U+%04lX>", TRUE);
512 }
513
514 /*
515 * Is a given character a "binary" character?
516 */
binary_char(LWCHAR c)517 public int binary_char(LWCHAR c)
518 {
519 if (utf_mode)
520 return (is_ubin_char(c));
521 c &= 0377;
522 return (chardef[c] & IS_BINARY_CHAR);
523 }
524
525 /*
526 * Is a given character a "control" character?
527 */
control_char(LWCHAR c)528 public int control_char(LWCHAR c)
529 {
530 c &= 0377;
531 return (chardef[c] & IS_CONTROL_CHAR);
532 }
533
534 /*
535 * Return the printable form of a character.
536 * For example, in the "ascii" charset '\3' is printed as "^C".
537 */
prchar(LWCHAR c)538 public char * prchar(LWCHAR c)
539 {
540 /* {{ This buffer can be overrun if LESSBINFMT is a long string. }} */
541 static char buf[MAX_PRCHAR_LEN+1];
542
543 c &= 0377;
544 if ((c < 128 || !utf_mode) && !control_char(c))
545 SNPRINTF1(buf, sizeof(buf), "%c", (int) c);
546 else if (c == ESC)
547 strcpy(buf, "ESC");
548 #if IS_EBCDIC_HOST
549 else if (!binary_char(c) && c < 64)
550 SNPRINTF1(buf, sizeof(buf), "^%c",
551 /*
552 * This array roughly inverts CONTROL() #defined in less.h,
553 * and should be kept in sync with CONTROL() and IBM-1047.
554 */
555 "@ABC.I.?...KLMNO"
556 "PQRS.JH.XY.."
557 "\\]^_"
558 "......W[.....EFG"
559 "..V....D....TU.Z"[c]);
560 #else
561 else if (c < 128 && !control_char(c ^ 0100))
562 SNPRINTF1(buf, sizeof(buf), "^%c", (int) (c ^ 0100));
563 #endif
564 else
565 SNPRINTF1(buf, sizeof(buf), binfmt, c);
566 return (buf);
567 }
568
569 /*
570 * Return the printable form of a UTF-8 character.
571 */
prutfchar(LWCHAR ch)572 public char * prutfchar(LWCHAR ch)
573 {
574 static char buf[MAX_PRCHAR_LEN+1];
575
576 if (ch == ESC)
577 strcpy(buf, "ESC");
578 else if (ch < 128 && control_char(ch))
579 {
580 if (!control_char(ch ^ 0100))
581 SNPRINTF1(buf, sizeof(buf), "^%c", ((char) ch) ^ 0100);
582 else
583 SNPRINTF1(buf, sizeof(buf), binfmt, (char) ch);
584 } else if (is_ubin_char(ch))
585 {
586 SNPRINTF1(buf, sizeof(buf), utfbinfmt, ch);
587 } else
588 {
589 char *p = buf;
590 if (ch >= 0x80000000)
591 ch = 0xFFFD; /* REPLACEMENT CHARACTER */
592 put_wchar(&p, ch);
593 *p = '\0';
594 }
595 return (buf);
596 }
597
598 /*
599 * Get the length of a UTF-8 character in bytes.
600 */
utf_len(int ch)601 public int utf_len(int ch)
602 {
603 if ((ch & 0x80) == 0)
604 return 1;
605 if ((ch & 0xE0) == 0xC0)
606 return 2;
607 if ((ch & 0xF0) == 0xE0)
608 return 3;
609 if ((ch & 0xF8) == 0xF0)
610 return 4;
611 if ((ch & 0xFC) == 0xF8)
612 return 5;
613 if ((ch & 0xFE) == 0xFC)
614 return 6;
615 /* Invalid UTF-8 encoding. */
616 return 1;
617 }
618
619 /*
620 * Does the parameter point to the lead byte of a well-formed UTF-8 character?
621 */
is_utf8_well_formed(char * ss,int slen)622 public int is_utf8_well_formed(char *ss, int slen)
623 {
624 int i;
625 int len;
626 unsigned char *s = (unsigned char *) ss;
627
628 if (IS_UTF8_INVALID(s[0]))
629 return (0);
630
631 len = utf_len(s[0]);
632 if (len > slen)
633 return (0);
634 if (len == 1)
635 return (1);
636 if (len == 2)
637 {
638 if (s[0] < 0xC2)
639 return (0);
640 } else
641 {
642 unsigned char mask;
643 mask = (~((1 << (8-len)) - 1)) & 0xFF;
644 if (s[0] == mask && (s[1] & mask) == 0x80)
645 return (0);
646 }
647
648 for (i = 1; i < len; i++)
649 if (!IS_UTF8_TRAIL(s[i]))
650 return (0);
651 return (1);
652 }
653
654 /*
655 * Skip bytes until a UTF-8 lead byte (11xxxxxx) or ASCII byte (0xxxxxxx) is found.
656 */
utf_skip_to_lead(char ** pp,char * limit)657 public void utf_skip_to_lead(char **pp, char *limit)
658 {
659 do {
660 ++(*pp);
661 } while (*pp < limit && !IS_UTF8_LEAD((*pp)[0] & 0377) && !IS_ASCII_OCTET((*pp)[0]));
662 }
663
664
665 /*
666 * Get the value of a UTF-8 character.
667 */
get_wchar(constant char * p)668 public LWCHAR get_wchar(constant char *p)
669 {
670 switch (utf_len(p[0]))
671 {
672 case 1:
673 default:
674 /* 0xxxxxxx */
675 return (LWCHAR)
676 (p[0] & 0xFF);
677 case 2:
678 /* 110xxxxx 10xxxxxx */
679 return (LWCHAR) (
680 ((p[0] & 0x1F) << 6) |
681 (p[1] & 0x3F));
682 case 3:
683 /* 1110xxxx 10xxxxxx 10xxxxxx */
684 return (LWCHAR) (
685 ((p[0] & 0x0F) << 12) |
686 ((p[1] & 0x3F) << 6) |
687 (p[2] & 0x3F));
688 case 4:
689 /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
690 return (LWCHAR) (
691 ((p[0] & 0x07) << 18) |
692 ((p[1] & 0x3F) << 12) |
693 ((p[2] & 0x3F) << 6) |
694 (p[3] & 0x3F));
695 case 5:
696 /* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
697 return (LWCHAR) (
698 ((p[0] & 0x03) << 24) |
699 ((p[1] & 0x3F) << 18) |
700 ((p[2] & 0x3F) << 12) |
701 ((p[3] & 0x3F) << 6) |
702 (p[4] & 0x3F));
703 case 6:
704 /* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
705 return (LWCHAR) (
706 ((p[0] & 0x01) << 30) |
707 ((p[1] & 0x3F) << 24) |
708 ((p[2] & 0x3F) << 18) |
709 ((p[3] & 0x3F) << 12) |
710 ((p[4] & 0x3F) << 6) |
711 (p[5] & 0x3F));
712 }
713 }
714
715 /*
716 * Store a character into a UTF-8 string.
717 */
put_wchar(char ** pp,LWCHAR ch)718 public void put_wchar(char **pp, LWCHAR ch)
719 {
720 if (!utf_mode || ch < 0x80)
721 {
722 /* 0xxxxxxx */
723 *(*pp)++ = (char) ch;
724 } else if (ch < 0x800)
725 {
726 /* 110xxxxx 10xxxxxx */
727 *(*pp)++ = (char) (0xC0 | ((ch >> 6) & 0x1F));
728 *(*pp)++ = (char) (0x80 | (ch & 0x3F));
729 } else if (ch < 0x10000)
730 {
731 /* 1110xxxx 10xxxxxx 10xxxxxx */
732 *(*pp)++ = (char) (0xE0 | ((ch >> 12) & 0x0F));
733 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
734 *(*pp)++ = (char) (0x80 | (ch & 0x3F));
735 } else if (ch < 0x200000)
736 {
737 /* 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
738 *(*pp)++ = (char) (0xF0 | ((ch >> 18) & 0x07));
739 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F));
740 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
741 *(*pp)++ = (char) (0x80 | (ch & 0x3F));
742 } else if (ch < 0x4000000)
743 {
744 /* 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
745 *(*pp)++ = (char) (0xF0 | ((ch >> 24) & 0x03));
746 *(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F));
747 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F));
748 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
749 *(*pp)++ = (char) (0x80 | (ch & 0x3F));
750 } else
751 {
752 /* 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx */
753 *(*pp)++ = (char) (0xF0 | ((ch >> 30) & 0x01));
754 *(*pp)++ = (char) (0x80 | ((ch >> 24) & 0x3F));
755 *(*pp)++ = (char) (0x80 | ((ch >> 18) & 0x3F));
756 *(*pp)++ = (char) (0x80 | ((ch >> 12) & 0x3F));
757 *(*pp)++ = (char) (0x80 | ((ch >> 6) & 0x3F));
758 *(*pp)++ = (char) (0x80 | (ch & 0x3F));
759 }
760 }
761
762 /*
763 * Step forward or backward one character in a string.
764 */
step_char(char ** pp,signed int dir,constant char * limit)765 public LWCHAR step_char(char **pp, signed int dir, constant char *limit)
766 {
767 LWCHAR ch;
768 int len;
769 char *p = *pp;
770
771 if (!utf_mode)
772 {
773 /* It's easy if chars are one byte. */
774 if (dir > 0)
775 ch = (LWCHAR) (unsigned char) ((p < limit) ? *p++ : 0);
776 else
777 ch = (LWCHAR) (unsigned char) ((p > limit) ? *--p : 0);
778 } else if (dir > 0)
779 {
780 len = utf_len(*p);
781 if (p + len > limit)
782 {
783 ch = 0;
784 p = (char *) limit;
785 } else
786 {
787 ch = get_wchar(p);
788 p += len;
789 }
790 } else
791 {
792 while (p > limit && IS_UTF8_TRAIL(p[-1]))
793 p--;
794 if (p > limit)
795 ch = get_wchar(--p);
796 else
797 ch = 0;
798 }
799 *pp = p;
800 return ch;
801 }
802
803 /*
804 * Unicode characters data
805 * Actual data is in the generated *.uni files.
806 */
807
808 #define DECLARE_RANGE_TABLE_START(name) \
809 static struct wchar_range name##_array[] = {
810 #define DECLARE_RANGE_TABLE_END(name) \
811 }; struct wchar_range_table name##_table = { name##_array, sizeof(name##_array)/sizeof(*name##_array) };
812
813 DECLARE_RANGE_TABLE_START(compose)
814 #include "compose.uni"
815 DECLARE_RANGE_TABLE_END(compose)
816
817 DECLARE_RANGE_TABLE_START(ubin)
818 #include "ubin.uni"
819 DECLARE_RANGE_TABLE_END(ubin)
820
821 DECLARE_RANGE_TABLE_START(wide)
822 #include "wide.uni"
823 DECLARE_RANGE_TABLE_END(wide)
824
825 DECLARE_RANGE_TABLE_START(fmt)
826 #include "fmt.uni"
827 DECLARE_RANGE_TABLE_END(fmt)
828
829 /* comb_table is special pairs, not ranges. */
830 static struct wchar_range comb_table[] = {
831 {0x0644,0x0622}, {0x0644,0x0623}, {0x0644,0x0625}, {0x0644,0x0627},
832 };
833
834
is_in_table(LWCHAR ch,struct wchar_range_table * table)835 static int is_in_table(LWCHAR ch, struct wchar_range_table *table)
836 {
837 int hi;
838 int lo;
839
840 /* Binary search in the table. */
841 if (table->table == NULL || table->count == 0 || ch < table->table[0].first)
842 return 0;
843 lo = 0;
844 hi = table->count - 1;
845 while (lo <= hi)
846 {
847 int mid = (lo + hi) / 2;
848 if (ch > table->table[mid].last)
849 lo = mid + 1;
850 else if (ch < table->table[mid].first)
851 hi = mid - 1;
852 else
853 return 1;
854 }
855 return 0;
856 }
857
858 /*
859 * Is a character a UTF-8 composing character?
860 * If a composing character follows any char, the two combine into one glyph.
861 */
is_composing_char(LWCHAR ch)862 public int is_composing_char(LWCHAR ch)
863 {
864 if (is_in_table(ch, &user_prt_table)) return 0;
865 return is_in_table(ch, &user_compose_table) ||
866 is_in_table(ch, &compose_table) ||
867 (bs_mode != BS_CONTROL && is_in_table(ch, &fmt_table));
868 }
869
870 /*
871 * Should this UTF-8 character be treated as binary?
872 */
is_ubin_char(LWCHAR ch)873 public int is_ubin_char(LWCHAR ch)
874 {
875 if (is_in_table(ch, &user_prt_table)) return 0;
876 return is_in_table(ch, &user_ubin_table) ||
877 is_in_table(ch, &ubin_table) ||
878 (bs_mode == BS_CONTROL && is_in_table(ch, &fmt_table));
879 }
880
881 /*
882 * Is this a double width UTF-8 character?
883 */
is_wide_char(LWCHAR ch)884 public int is_wide_char(LWCHAR ch)
885 {
886 return is_in_table(ch, &user_wide_table) ||
887 is_in_table(ch, &wide_table);
888 }
889
890 /*
891 * Is a character a UTF-8 combining character?
892 * A combining char acts like an ordinary char, but if it follows
893 * a specific char (not any char), the two combine into one glyph.
894 */
is_combining_char(LWCHAR ch1,LWCHAR ch2)895 public int is_combining_char(LWCHAR ch1, LWCHAR ch2)
896 {
897 /* The table is small; use linear search. */
898 int i;
899 for (i = 0; i < sizeof(comb_table)/sizeof(*comb_table); i++)
900 {
901 if (ch1 == comb_table[i].first &&
902 ch2 == comb_table[i].last)
903 return 1;
904 }
905 return 0;
906 }
907
908