1 /* Header for multibyte character handler.
2    Copyright (C) 1995, 1997, 1998 Electrotechnical Laboratory, JAPAN.
3      Licensed to the Free Software Foundation.
4    Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
5      National Institute of Advanced Industrial Science and Technology (AIST)
6      Registration Number H13PRO009
7 
8 This file is part of GNU Emacs.
9 
10 GNU Emacs is free software: you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation, either version 3 of the License, or (at
13 your option) any later version.
14 
15 GNU Emacs is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18 GNU General Public License for more details.
19 
20 You should have received a copy of the GNU General Public License
21 along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
22 
23 #ifndef EMACS_CHARACTER_H
24 #define EMACS_CHARACTER_H
25 
26 #include <verify.h>
27 #include "lisp.h"
28 
29 INLINE_HEADER_BEGIN
30 
31 /* character code	1st byte   byte sequence
32    --------------	--------   -------------
33         0-7F		00..7F	   0xxxxxxx
34        80-7FF		C2..DF	   110xxxxx 10xxxxxx
35       800-FFFF		E0..EF	   1110xxxx 10xxxxxx 10xxxxxx
36     10000-1FFFFF	F0..F7	   11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
37    200000-3FFF7F	F8	   11111000 1000xxxx 10xxxxxx 10xxxxxx 10xxxxxx
38    3FFF80-3FFFFF	C0..C1	   1100000x 10xxxxxx (for eight-bit-char)
39    400000-...		invalid
40 
41    invalid 1st byte	80..BF	   10xxxxxx
42 			F9..FF	   11111xxx (xxx != 000)
43 */
44 
45 /* Maximum character code ((1 << CHARACTERBITS) - 1).  */
46 #define MAX_CHAR  0x3FFFFF
47 
48 /* Maximum Unicode character code.  */
49 #define MAX_UNICODE_CHAR 0x10FFFF
50 
51 /* Maximum N-byte character codes.  */
52 #define MAX_1_BYTE_CHAR 0x7F
53 #define MAX_2_BYTE_CHAR 0x7FF
54 #define MAX_3_BYTE_CHAR 0xFFFF
55 #define MAX_4_BYTE_CHAR 0x1FFFFF
56 #define MAX_5_BYTE_CHAR 0x3FFF7F
57 
58 /* Minimum leading code of multibyte characters.  */
59 #define MIN_MULTIBYTE_LEADING_CODE 0xC0
60 /* Maximum leading code of multibyte characters.  Note: this must be
61    updated if we ever increase MAX_CHAR above.  */
62 #define MAX_MULTIBYTE_LEADING_CODE 0xF8
63 
64 /* Unicode character values.  */
65 enum
66 {
67   NO_BREAK_SPACE = 0x00A0,
68   SOFT_HYPHEN = 0x00AD,
69   ZERO_WIDTH_NON_JOINER = 0x200C,
70   ZERO_WIDTH_JOINER = 0x200D,
71   HYPHEN = 0x2010,
72   NON_BREAKING_HYPHEN = 0x2011,
73   LEFT_SINGLE_QUOTATION_MARK = 0x2018,
74   RIGHT_SINGLE_QUOTATION_MARK = 0x2019,
75   PARAGRAPH_SEPARATOR = 0x2029,
76   LEFT_POINTING_ANGLE_BRACKET = 0x2329,
77   RIGHT_POINTING_ANGLE_BRACKET = 0x232A,
78   LEFT_ANGLE_BRACKET = 0x3008,
79   RIGHT_ANGLE_BRACKET = 0x3009,
80   OBJECT_REPLACEMENT_CHARACTER = 0xFFFC,
81 };
82 
83 /* UTF-8 encodings.  Use \x escapes, so they are portable to pre-C11
84    compilers and can be concatenated with ordinary string literals.  */
85 #define uLSQM "\xE2\x80\x98" /* U+2018 LEFT SINGLE QUOTATION MARK */
86 #define uRSQM "\xE2\x80\x99" /* U+2019 RIGHT SINGLE QUOTATION MARK */
87 
88 /* Nonzero iff C is a character that corresponds to a raw 8-bit
89    byte.  */
90 #define CHAR_BYTE8_P(c) ((c) > MAX_5_BYTE_CHAR)
91 
92 /* Return the character code for raw 8-bit byte BYTE.  */
93 #define BYTE8_TO_CHAR(byte) ((byte) + 0x3FFF00)
94 
95 #define UNIBYTE_TO_CHAR(byte) \
96   (ASCII_CHAR_P (byte) ? (byte) : BYTE8_TO_CHAR (byte))
97 
98 /* Return the raw 8-bit byte for character C.  */
99 #define CHAR_TO_BYTE8(c) (CHAR_BYTE8_P (c) ? (c) - 0x3FFF00 : (c & 0xFF))
100 
101 /* Return the raw 8-bit byte for character C,
102    or -1 if C doesn't correspond to a byte.  */
103 #define CHAR_TO_BYTE_SAFE(c)						\
104   (ASCII_CHAR_P (c) ? c : (CHAR_BYTE8_P (c) ? (c) - 0x3FFF00 : -1))
105 
106 /* Nonzero iff BYTE is the 1st byte of a multibyte form of a character
107    that corresponds to a raw 8-bit byte.  */
108 #define CHAR_BYTE8_HEAD_P(byte) ((byte) == 0xC0 || (byte) == 0xC1)
109 
110 /* If C is not ASCII, make it unibyte. */
111 #define MAKE_CHAR_UNIBYTE(c)	\
112   do {				\
113     if (! ASCII_CHAR_P (c))	\
114       c = CHAR_TO_BYTE8 (c);	\
115   } while (false)
116 
117 
118 /* If C is not ASCII, make it multibyte.  Assumes C < 256.  */
119 #define MAKE_CHAR_MULTIBYTE(c) \
120   (eassert ((c) >= 0 && (c) < 256), (c) = UNIBYTE_TO_CHAR (c))
121 
122 /* This is the maximum byte length of multibyte form.  */
123 #define MAX_MULTIBYTE_LENGTH 5
124 
125 /* Nonzero iff X is a character.  */
126 #define CHARACTERP(x) (FIXNATP (x) && XFIXNAT (x) <= MAX_CHAR)
127 
128 /* Nonzero iff C is valid as a character code.  */
129 #define CHAR_VALID_P(c) UNSIGNED_CMP (c, <=, MAX_CHAR)
130 
131 /* Check if Lisp object X is a character or not.  */
132 #define CHECK_CHARACTER(x) \
133   CHECK_TYPE (CHARACTERP (x), Qcharacterp, x)
134 
135 #define CHECK_CHARACTER_CAR(x) \
136   do {					\
137     Lisp_Object tmp = XCAR (x);		\
138     CHECK_CHARACTER (tmp);		\
139   } while (false)
140 
141 #define CHECK_CHARACTER_CDR(x) \
142   do {					\
143     Lisp_Object tmp = XCDR (x);		\
144     CHECK_CHARACTER (tmp);		\
145   } while (false)
146 
147 /* Nonzero iff C is a character of code less than 0x100.  */
148 #define SINGLE_BYTE_CHAR_P(c) UNSIGNED_CMP (c, <, 0x100)
149 
150 /* Nonzero if character C has a printable glyph.  */
151 #define CHAR_PRINTABLE_P(c)	\
152   (((c) >= 32 && (c) < 127)	\
153    || ! NILP (CHAR_TABLE_REF (Vprintable_chars, (c))))
154 
155 /* Return byte length of multibyte form for character C.  */
156 #define CHAR_BYTES(c)			\
157   ( (c) <= MAX_1_BYTE_CHAR ? 1		\
158     : (c) <= MAX_2_BYTE_CHAR ? 2	\
159     : (c) <= MAX_3_BYTE_CHAR ? 3	\
160     : (c) <= MAX_4_BYTE_CHAR ? 4	\
161     : (c) <= MAX_5_BYTE_CHAR ? 5	\
162     : 2)
163 
164 
165 /* Return the leading code of multibyte form of C.  */
166 #define CHAR_LEADING_CODE(c)				\
167   ((c) <= MAX_1_BYTE_CHAR ? c				\
168    : (c) <= MAX_2_BYTE_CHAR ? (0xC0 | ((c) >> 6))	\
169    : (c) <= MAX_3_BYTE_CHAR ? (0xE0 | ((c) >> 12))	\
170    : (c) <= MAX_4_BYTE_CHAR ? (0xF0 | ((c) >> 18))	\
171    : (c) <= MAX_5_BYTE_CHAR ? 0xF8			\
172    : (0xC0 | (((c) >> 6) & 0x01)))
173 
174 
175 /* Store multibyte form of the character C in P.  The caller should
176    allocate at least MAX_MULTIBYTE_LENGTH bytes area at P in advance.
177    Returns the length of the multibyte form.  */
178 
179 #define CHAR_STRING(c, p)			\
180   (UNSIGNED_CMP (c, <=, MAX_1_BYTE_CHAR)	\
181    ? ((p)[0] = (c),				\
182       1)					\
183    : UNSIGNED_CMP (c, <=, MAX_2_BYTE_CHAR)	\
184    ? ((p)[0] = (0xC0 | ((c) >> 6)),		\
185       (p)[1] = (0x80 | ((c) & 0x3F)),		\
186       2)					\
187    : UNSIGNED_CMP (c, <=, MAX_3_BYTE_CHAR)	\
188    ? ((p)[0] = (0xE0 | ((c) >> 12)),		\
189       (p)[1] = (0x80 | (((c) >> 6) & 0x3F)),	\
190       (p)[2] = (0x80 | ((c) & 0x3F)),		\
191       3)					\
192    : verify_expr (sizeof (c) <= sizeof (unsigned), char_string (c, p)))
193 
194 /* Store multibyte form of byte B in P.  The caller should allocate at
195    least MAX_MULTIBYTE_LENGTH bytes area at P in advance.  Returns the
196    length of the multibyte form.  */
197 
198 #define BYTE8_STRING(b, p)			\
199   ((p)[0] = (0xC0 | (((b) >> 6) & 0x01)),	\
200    (p)[1] = (0x80 | ((b) & 0x3F)),		\
201    2)
202 
203 
204 /* Store multibyte form of the character C in P and advance P to the
205    end of the multibyte form.  The caller should allocate at least
206    MAX_MULTIBYTE_LENGTH bytes area at P in advance.  */
207 
208 #define CHAR_STRING_ADVANCE(c, p)		\
209   do {						\
210     if ((c) <= MAX_1_BYTE_CHAR)			\
211       *(p)++ = (c);				\
212     else if ((c) <= MAX_2_BYTE_CHAR)		\
213       *(p)++ = (0xC0 | ((c) >> 6)),		\
214 	*(p)++ = (0x80 | ((c) & 0x3F));		\
215     else if ((c) <= MAX_3_BYTE_CHAR)		\
216       *(p)++ = (0xE0 | ((c) >> 12)),		\
217 	*(p)++ = (0x80 | (((c) >> 6) & 0x3F)),	\
218 	*(p)++ = (0x80 | ((c) & 0x3F));		\
219     else					\
220       {						\
221 	verify (sizeof (c) <= sizeof (unsigned));	\
222 	(p) += char_string (c, p);		\
223       }						\
224   } while (false)
225 
226 
227 /* Nonzero iff BYTE starts a non-ASCII character in a multibyte
228    form.  */
229 #define LEADING_CODE_P(byte) (((byte) & 0xC0) == 0xC0)
230 
231 /* Nonzero iff BYTE is a trailing code of a non-ASCII character in a
232    multibyte form.  */
233 #define TRAILING_CODE_P(byte) (((byte) & 0xC0) == 0x80)
234 
235 /* Nonzero iff BYTE starts a character in a multibyte form.
236    This is equivalent to:
237 	(ASCII_CHAR_P (byte) || LEADING_CODE_P (byte))  */
238 #define CHAR_HEAD_P(byte) (((byte) & 0xC0) != 0x80)
239 
240 /* How many bytes a character that starts with BYTE occupies in a
241    multibyte form.  Unlike MULTIBYTE_LENGTH below, this macro does not
242    validate the multibyte form, but looks only at its first byte.  */
243 #define BYTES_BY_CHAR_HEAD(byte)	\
244   (!((byte) & 0x80) ? 1			\
245    : !((byte) & 0x20) ? 2		\
246    : !((byte) & 0x10) ? 3		\
247    : !((byte) & 0x08) ? 4		\
248    : 5)
249 
250 
251 /* The byte length of multibyte form at unibyte string P ending at
252    PEND.  If the string doesn't point to a valid multibyte form,
253    return 0.  Unlike BYTES_BY_CHAR_HEAD, this macro validates the
254    multibyte form.  */
255 
256 #define MULTIBYTE_LENGTH(p, pend)				\
257   (p >= pend ? 0						\
258    : !((p)[0] & 0x80) ? 1					\
259    : ((p + 1 >= pend) || (((p)[1] & 0xC0) != 0x80)) ? 0		\
260    : ((p)[0] & 0xE0) == 0xC0 ? 2				\
261    : ((p + 2 >= pend) || (((p)[2] & 0xC0) != 0x80)) ? 0		\
262    : ((p)[0] & 0xF0) == 0xE0 ? 3				\
263    : ((p + 3 >= pend) || (((p)[3] & 0xC0) != 0x80)) ? 0		\
264    : ((p)[0] & 0xF8) == 0xF0 ? 4				\
265    : ((p + 4 >= pend) || (((p)[4] & 0xC0) != 0x80)) ? 0		\
266    : (p)[0] == 0xF8 && ((p)[1] & 0xF0) == 0x80 ? 5		\
267    : 0)
268 
269 
270 /* Like MULTIBYTE_LENGTH, but don't check the ending address.  The
271    multibyte form is still validated, unlike BYTES_BY_CHAR_HEAD.  */
272 
273 #define MULTIBYTE_LENGTH_NO_CHECK(p)			\
274   (!((p)[0] & 0x80) ? 1					\
275    : ((p)[1] & 0xC0) != 0x80 ? 0			\
276    : ((p)[0] & 0xE0) == 0xC0 ? 2			\
277    : ((p)[2] & 0xC0) != 0x80 ? 0			\
278    : ((p)[0] & 0xF0) == 0xE0 ? 3			\
279    : ((p)[3] & 0xC0) != 0x80 ? 0			\
280    : ((p)[0] & 0xF8) == 0xF0 ? 4			\
281    : ((p)[4] & 0xC0) != 0x80 ? 0			\
282    : (p)[0] == 0xF8 && ((p)[1] & 0xF0) == 0x80 ? 5	\
283    : 0)
284 
285 /* If P is before LIMIT, advance P to the next character boundary.
286    Assumes that P is already at a character boundary of the same
287    multibyte form whose end address is LIMIT.  */
288 
289 #define NEXT_CHAR_BOUNDARY(p, limit)	\
290   do {					\
291     if ((p) < (limit))			\
292       (p) += BYTES_BY_CHAR_HEAD (*(p));	\
293   } while (false)
294 
295 
296 /* If P is after LIMIT, advance P to the previous character boundary.
297    Assumes that P is already at a character boundary of the same
298    multibyte form whose beginning address is LIMIT.  */
299 
300 #define PREV_CHAR_BOUNDARY(p, limit)					\
301   do {									\
302     if ((p) > (limit))							\
303       {									\
304 	const unsigned char *chp = (p);					\
305 	do {								\
306 	  chp--;							\
307 	} while (chp >= limit && ! CHAR_HEAD_P (*chp));			\
308 	(p) = (BYTES_BY_CHAR_HEAD (*chp) == (p) - chp) ? chp : (p) - 1;	\
309       }									\
310   } while (false)
311 
312 /* Return the character code of character whose multibyte form is at P.  */
313 
314 #define STRING_CHAR(p)						\
315   (!((p)[0] & 0x80)						\
316    ? (p)[0]							\
317    : ! ((p)[0] & 0x20)						\
318    ? (((((p)[0] & 0x1F) << 6)					\
319        | ((p)[1] & 0x3F))					\
320       + (((unsigned char) (p)[0]) < 0xC2 ? 0x3FFF80 : 0))	\
321    : ! ((p)[0] & 0x10)						\
322    ? ((((p)[0] & 0x0F) << 12)					\
323       | (((p)[1] & 0x3F) << 6)					\
324       | ((p)[2] & 0x3F))					\
325    : string_char ((p), NULL, NULL))
326 
327 
328 /* Like STRING_CHAR, but set ACTUAL_LEN to the length of multibyte
329    form.  */
330 
331 #define STRING_CHAR_AND_LENGTH(p, actual_len)			\
332   (!((p)[0] & 0x80)						\
333    ? ((actual_len) = 1, (p)[0])					\
334    : ! ((p)[0] & 0x20)						\
335    ? ((actual_len) = 2,						\
336       (((((p)[0] & 0x1F) << 6)					\
337 	| ((p)[1] & 0x3F))					\
338        + (((unsigned char) (p)[0]) < 0xC2 ? 0x3FFF80 : 0)))	\
339    : ! ((p)[0] & 0x10)						\
340    ? ((actual_len) = 3,						\
341       ((((p)[0] & 0x0F) << 12)					\
342        | (((p)[1] & 0x3F) << 6)					\
343        | ((p)[2] & 0x3F)))					\
344    : string_char ((p), NULL, &actual_len))
345 
346 
347 /* Like STRING_CHAR, but advance P to the end of multibyte form.  */
348 
349 #define STRING_CHAR_ADVANCE(p)					\
350   (!((p)[0] & 0x80)						\
351    ? *(p)++							\
352    : ! ((p)[0] & 0x20)						\
353    ? ((p) += 2,							\
354       ((((p)[-2] & 0x1F) << 6)					\
355        | ((p)[-1] & 0x3F)					\
356        | ((unsigned char) ((p)[-2]) < 0xC2 ? 0x3FFF80 : 0)))	\
357    : ! ((p)[0] & 0x10)						\
358    ? ((p) += 3,							\
359       ((((p)[-3] & 0x0F) << 12)					\
360        | (((p)[-2] & 0x3F) << 6)				\
361        | ((p)[-1] & 0x3F)))					\
362    : string_char ((p), &(p), NULL))
363 
364 
365 /* Fetch the "next" character from Lisp string STRING at byte position
366    BYTEIDX, character position CHARIDX.  Store it into OUTPUT.
367 
368    All the args must be side-effect-free.
369    BYTEIDX and CHARIDX must be lvalues;
370    we increment them past the character fetched.  */
371 
372 #define FETCH_STRING_CHAR_ADVANCE(OUTPUT, STRING, CHARIDX, BYTEIDX)	\
373   do                                                                    \
374     {									\
375       CHARIDX++;							\
376       if (STRING_MULTIBYTE (STRING))					\
377 	{								\
378 	  unsigned char *chp = &SDATA (STRING)[BYTEIDX];		\
379 	  int chlen;							\
380 									\
381 	  OUTPUT = STRING_CHAR_AND_LENGTH (chp, chlen);			\
382 	  BYTEIDX += chlen;						\
383 	}								\
384       else								\
385 	{								\
386 	  OUTPUT = SREF (STRING, BYTEIDX);				\
387 	  BYTEIDX++;							\
388 	}								\
389     }									\
390   while (false)
391 
392 /* Like FETCH_STRING_CHAR_ADVANCE, but return a multibyte character
393    even if STRING is unibyte.  */
394 
395 #define FETCH_STRING_CHAR_AS_MULTIBYTE_ADVANCE(OUTPUT, STRING, CHARIDX, BYTEIDX) \
396   do                                                                          \
397     {									      \
398       CHARIDX++;							      \
399       if (STRING_MULTIBYTE (STRING))					      \
400 	{								      \
401 	  unsigned char *chp = &SDATA (STRING)[BYTEIDX];		      \
402 	  int chlen;							      \
403 									      \
404 	  OUTPUT = STRING_CHAR_AND_LENGTH (chp, chlen);			      \
405 	  BYTEIDX += chlen;						      \
406 	}								      \
407       else								      \
408 	{								      \
409 	  OUTPUT = SREF (STRING, BYTEIDX);				      \
410 	  BYTEIDX++;							      \
411 	  MAKE_CHAR_MULTIBYTE (OUTPUT);					      \
412 	}								      \
413     }									      \
414   while (false)
415 
416 
417 /* Like FETCH_STRING_CHAR_ADVANCE, but assumes STRING is multibyte.  */
418 
419 #define FETCH_STRING_CHAR_ADVANCE_NO_CHECK(OUTPUT, STRING, CHARIDX, BYTEIDX) \
420   do    								     \
421     {									     \
422       unsigned char *fetch_ptr = &SDATA (STRING)[BYTEIDX];		     \
423       int fetch_len;							     \
424 									     \
425       OUTPUT = STRING_CHAR_AND_LENGTH (fetch_ptr, fetch_len);		     \
426       BYTEIDX += fetch_len;						     \
427       CHARIDX++;							     \
428     }									     \
429   while (false)
430 
431 
432 /* Like FETCH_STRING_CHAR_ADVANCE, but fetch character from the current
433    buffer.  */
434 
435 #define FETCH_CHAR_ADVANCE(OUTPUT, CHARIDX, BYTEIDX)		\
436   do    							\
437     {								\
438       CHARIDX++;						\
439       if (!NILP (BVAR (current_buffer, enable_multibyte_characters)))	\
440 	{							\
441 	  unsigned char *chp = BYTE_POS_ADDR (BYTEIDX);		\
442 	  int chlen;						\
443 								\
444 	  OUTPUT = STRING_CHAR_AND_LENGTH (chp, chlen);		\
445 	  BYTEIDX += chlen;					\
446 	}							\
447       else							\
448 	{							\
449 	  OUTPUT = *(BYTE_POS_ADDR (BYTEIDX));			\
450 	  BYTEIDX++;						\
451 	}							\
452     }								\
453   while (false)
454 
455 
456 /* Like FETCH_CHAR_ADVANCE, but assumes the current buffer is multibyte.  */
457 
458 #define FETCH_CHAR_ADVANCE_NO_CHECK(OUTPUT, CHARIDX, BYTEIDX)	\
459   do    							\
460     {								\
461       unsigned char *chp = BYTE_POS_ADDR (BYTEIDX);		\
462       int chlen;							\
463 								\
464       OUTPUT = STRING_CHAR_AND_LENGTH (chp, chlen);		\
465       BYTEIDX += chlen;						\
466       CHARIDX++;						\
467     }								\
468   while (false)
469 
470 
471 /* Increment the buffer byte position POS_BYTE of the current buffer to
472    the next character boundary.  No range checking of POS.  */
473 
474 #define INC_POS(pos_byte)				\
475   do {							\
476     unsigned char *chp = BYTE_POS_ADDR (pos_byte);	\
477     pos_byte += BYTES_BY_CHAR_HEAD (*chp);		\
478   } while (false)
479 
480 
481 /* Decrement the buffer byte position POS_BYTE of the current buffer to
482    the previous character boundary.  No range checking of POS.  */
483 
484 #define DEC_POS(pos_byte)			\
485   do {						\
486     unsigned char *chp;				\
487     						\
488     pos_byte--;					\
489     if (pos_byte < GPT_BYTE)			\
490       chp = BEG_ADDR + pos_byte - BEG_BYTE;	\
491     else					\
492       chp = BEG_ADDR + GAP_SIZE + pos_byte - BEG_BYTE; \
493     while (!CHAR_HEAD_P (*chp))			\
494       {						\
495 	chp--;					\
496 	pos_byte--;				\
497       }						\
498   } while (false)
499 
500 /* Increment both CHARPOS and BYTEPOS, each in the appropriate way.  */
501 
502 #define INC_BOTH(charpos, bytepos)				\
503   do								\
504     {								\
505       (charpos)++;						\
506       if (NILP (BVAR (current_buffer, enable_multibyte_characters)))	\
507 	(bytepos)++;						\
508       else							\
509 	INC_POS ((bytepos));					\
510     }								\
511   while (false)
512 
513 
514 /* Decrement both CHARPOS and BYTEPOS, each in the appropriate way.  */
515 
516 #define DEC_BOTH(charpos, bytepos)				\
517   do								\
518     {								\
519       (charpos)--;						\
520       if (NILP (BVAR (current_buffer, enable_multibyte_characters)))	\
521 	(bytepos)--;						\
522       else							\
523 	DEC_POS ((bytepos));					\
524     }								\
525   while (false)
526 
527 
528 /* Increment the buffer byte position POS_BYTE of the current buffer to
529    the next character boundary.  This macro relies on the fact that
530    *GPT_ADDR and *Z_ADDR are always accessible and the values are
531    '\0'.  No range checking of POS_BYTE.  */
532 
533 #define BUF_INC_POS(buf, pos_byte)				\
534   do {								\
535     unsigned char *chp = BUF_BYTE_ADDRESS (buf, pos_byte);	\
536     pos_byte += BYTES_BY_CHAR_HEAD (*chp);			\
537   } while (false)
538 
539 
540 /* Decrement the buffer byte position POS_BYTE of the current buffer to
541    the previous character boundary.  No range checking of POS_BYTE.  */
542 
543 #define BUF_DEC_POS(buf, pos_byte)					\
544   do {									\
545     unsigned char *chp;							\
546     pos_byte--;								\
547     if (pos_byte < BUF_GPT_BYTE (buf))					\
548       chp = BUF_BEG_ADDR (buf) + pos_byte - BEG_BYTE;			\
549     else								\
550       chp = BUF_BEG_ADDR (buf) + BUF_GAP_SIZE (buf) + pos_byte - BEG_BYTE;\
551     while (!CHAR_HEAD_P (*chp))						\
552       {									\
553 	chp--;								\
554 	pos_byte--;							\
555       }									\
556   } while (false)
557 
558 
559 /* Return a non-outlandish value for the tab width.  */
560 
561 #define SANE_TAB_WIDTH(buf) sanitize_tab_width (BVAR (buf, tab_width))
562 
563 INLINE int
sanitize_tab_width(Lisp_Object width)564 sanitize_tab_width (Lisp_Object width)
565 {
566   return (FIXNUMP (width) && 0 < XFIXNUM (width) && XFIXNUM (width) <= 1000
567 	  ? XFIXNUM (width) : 8);
568 }
569 
570 /* Return the width of ASCII character C.  The width is measured by
571    how many columns C will occupy on the screen when displayed in the
572    current buffer.  */
573 
574 #define ASCII_CHAR_WIDTH(c)						\
575   (c < 0x20								\
576    ? (c == '\t'								\
577       ? SANE_TAB_WIDTH (current_buffer)					\
578       : (c == '\n' ? 0 : (NILP (BVAR (current_buffer, ctl_arrow)) ? 4 : 2)))	\
579    : (c < 0x7f								\
580       ? 1								\
581       : ((NILP (BVAR (current_buffer, ctl_arrow)) ? 4 : 2))))
582 
583 /* Return a non-outlandish value for a character width.  */
584 
585 INLINE int
sanitize_char_width(EMACS_INT width)586 sanitize_char_width (EMACS_INT width)
587 {
588   return 0 <= width && width <= 1000 ? width : 1000;
589 }
590 
591 /* Return the width of character C.  The width is measured by how many
592    columns C will occupy on the screen when displayed in the current
593    buffer.  The name CHARACTER_WIDTH avoids a collision with <limits.h>
594    CHAR_WIDTH when enabled; see ISO/IEC TS 18661-1:2014.  */
595 
596 #define CHARACTER_WIDTH(c)	\
597   (ASCII_CHAR_P (c)		\
598    ? ASCII_CHAR_WIDTH (c)	\
599    : sanitize_char_width (XFIXNUM (CHAR_TABLE_REF (Vchar_width_table, c))))
600 
601 /* If C is a variation selector, return the index of the
602    variation selector (1..256).  Otherwise, return 0.  */
603 
604 #define CHAR_VARIATION_SELECTOR_P(c)		\
605   ((c) < 0xFE00 ? 0				\
606    : (c) <= 0xFE0F ? (c) - 0xFE00 + 1		\
607    : (c) < 0xE0100 ? 0				\
608    : (c) <= 0xE01EF ? (c) - 0xE0100 + 17	\
609    : 0)
610 
611 /* Return true if C is a surrogate.  */
612 
613 INLINE bool
char_surrogate_p(int c)614 char_surrogate_p (int c)
615 {
616   return 0xD800 <= c && c <= 0xDFFF;
617 }
618 
619 /* Data type for Unicode general category.
620 
621    The order of members must be in sync with the 8th element of the
622    member of unidata-prop-alist (in admin/unidata/unidata-gen.el) for
623    Unicode character property `general-category'.  */
624 
625 typedef enum {
626   UNICODE_CATEGORY_UNKNOWN = 0,
627   UNICODE_CATEGORY_Lu,
628   UNICODE_CATEGORY_Ll,
629   UNICODE_CATEGORY_Lt,
630   UNICODE_CATEGORY_Lm,
631   UNICODE_CATEGORY_Lo,
632   UNICODE_CATEGORY_Mn,
633   UNICODE_CATEGORY_Mc,
634   UNICODE_CATEGORY_Me,
635   UNICODE_CATEGORY_Nd,
636   UNICODE_CATEGORY_Nl,
637   UNICODE_CATEGORY_No,
638   UNICODE_CATEGORY_Pc,
639   UNICODE_CATEGORY_Pd,
640   UNICODE_CATEGORY_Ps,
641   UNICODE_CATEGORY_Pe,
642   UNICODE_CATEGORY_Pi,
643   UNICODE_CATEGORY_Pf,
644   UNICODE_CATEGORY_Po,
645   UNICODE_CATEGORY_Sm,
646   UNICODE_CATEGORY_Sc,
647   UNICODE_CATEGORY_Sk,
648   UNICODE_CATEGORY_So,
649   UNICODE_CATEGORY_Zs,
650   UNICODE_CATEGORY_Zl,
651   UNICODE_CATEGORY_Zp,
652   UNICODE_CATEGORY_Cc,
653   UNICODE_CATEGORY_Cf,
654   UNICODE_CATEGORY_Cs,
655   UNICODE_CATEGORY_Co,
656   UNICODE_CATEGORY_Cn
657 } unicode_category_t;
658 
659 extern EMACS_INT char_resolve_modifier_mask (EMACS_INT) ATTRIBUTE_CONST;
660 extern int char_string (unsigned, unsigned char *);
661 extern int string_char (const unsigned char *,
662                         const unsigned char **, int *);
663 
664 extern int translate_char (Lisp_Object, int c);
665 extern ptrdiff_t count_size_as_multibyte (const unsigned char *, ptrdiff_t);
666 extern ptrdiff_t str_as_multibyte (unsigned char *, ptrdiff_t, ptrdiff_t,
667 				   ptrdiff_t *);
668 extern ptrdiff_t str_to_multibyte (unsigned char *, ptrdiff_t, ptrdiff_t);
669 extern ptrdiff_t str_as_unibyte (unsigned char *, ptrdiff_t);
670 extern ptrdiff_t str_to_unibyte (const unsigned char *, unsigned char *,
671                                  ptrdiff_t);
672 extern ptrdiff_t strwidth (const char *, ptrdiff_t);
673 extern ptrdiff_t c_string_width (const unsigned char *, ptrdiff_t, int,
674 				 ptrdiff_t *, ptrdiff_t *);
675 extern ptrdiff_t lisp_string_width (Lisp_Object, ptrdiff_t,
676 				    ptrdiff_t *, ptrdiff_t *);
677 
678 extern Lisp_Object Vchar_unify_table;
679 extern Lisp_Object string_escape_byte8 (Lisp_Object);
680 
681 extern bool alphabeticp (int);
682 extern bool alphanumericp (int);
683 extern bool graphicp (int);
684 extern bool printablep (int);
685 extern bool blankp (int);
686 
687 /* Return a translation table of id number ID.  */
688 #define GET_TRANSLATION_TABLE(id) \
689   (XCDR (XVECTOR (Vtranslation_table_vector)->contents[(id)]))
690 
691 /* Look up the element in char table OBJ at index CH, and return it as
692    an integer.  If the element is not a character, return CH itself.  */
693 
694 INLINE int
char_table_translate(Lisp_Object obj,int ch)695 char_table_translate (Lisp_Object obj, int ch)
696 {
697   /* This internal function is expected to be called with valid arguments,
698      so there is an eassert instead of CHECK_xxx for the sake of speed.  */
699   eassert (CHAR_VALID_P (ch));
700   eassert (CHAR_TABLE_P (obj));
701   obj = CHAR_TABLE_REF (obj, ch);
702   return CHARACTERP (obj) ? XFIXNUM (obj) : ch;
703 }
704 
705 extern signed char const hexdigit[];
706 
707 /* If C is a hexadecimal digit ('0'-'9', 'a'-'f', 'A'-'F'), return its
708    value (0-15).  Otherwise return -1.  */
709 
710 INLINE int
char_hexdigit(int c)711 char_hexdigit (int c)
712 {
713   return 0 <= c && c <= UCHAR_MAX ? hexdigit[c] - 1 : -1;
714 }
715 
716 INLINE_HEADER_END
717 
718 #endif /* EMACS_CHARACTER_H */
719