1/* Header for multibyte character handler.
2   Copyright (C) 2001, 2002, 2003, 2004, 2005,
3                 2006, 2007 Free Software Foundation, Inc.
4   Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
5     2005, 2006, 2007
6     National Institute of Advanced Industrial Science and Technology (AIST)
7     Registration Number H14PRO021
8
9This file is part of GNU Emacs.
10
11GNU Emacs is free software; you can redistribute it and/or modify
12it under the terms of the GNU General Public License as published by
13the Free Software Foundation; either version 2, or (at your option)
14any later version.
15
16GNU Emacs is distributed in the hope that it will be useful,
17but WITHOUT ANY WARRANTY; without even the implied warranty of
18MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19GNU General Public License for more details.
20
21You should have received a copy of the GNU General Public License
22along with GNU Emacs; see the file COPYING.  If not, write to
23the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
24Boston, MA 02110-1301, USA.  */
25
26#ifndef EMACS_CHARSET_H
27#define EMACS_CHARSET_H
28
29/* #define BYTE_COMBINING_DEBUG */
30
31/*** GENERAL NOTE on CHARACTER SET (CHARSET) ***
32
33  A character set ("charset" hereafter) is a meaningful collection
34  (i.e. language, culture, functionality, etc) of characters.  Emacs
35  handles multiple charsets at once.  Each charset corresponds to one
36  of the ISO charsets.  Emacs identifies a charset by a unique
37  identification number, whereas ISO identifies a charset by a triplet
38  of DIMENSION, CHARS and FINAL-CHAR.  So, hereafter, just saying
39  "charset" means an identification number (integer value).
40
41  The value range of charsets is 0x00, 0x81..0xFE.  There are four
42  kinds of charset depending on DIMENSION (1 or 2) and CHARS (94 or
43  96).  For instance, a charset of DIMENSION2_CHARS94 contains 94x94
44  characters.
45
46  Within Emacs Lisp, a charset is treated as a symbol which has a
47  property `charset'.  The property value is a vector containing
48  various information about the charset.  For readability of C code,
49  we use the following convention for C variable names:
50	charset_symbol: Emacs Lisp symbol of a charset
51	charset_id: Emacs Lisp integer of an identification number of a charset
52	charset: C integer of an identification number of a charset
53
54  Each charset (except for ascii) is assigned a base leading-code
55  (range 0x80..0x9E).  In addition, a charset of greater than 0xA0
56  (whose base leading-code is 0x9A..0x9D) is assigned an extended
57  leading-code (range 0xA0..0xFE).  In this case, each base
58  leading-code specifies the allowable range of extended leading-code
59  as shown in the table below.  A leading-code is used to represent a
60  character in Emacs' buffer and string.
61
62  We call a charset which has extended leading-code a "private
63  charset" because those are mainly for a charset which is not yet
64  registered by ISO.  On the contrary, we call a charset which does
65  not have extended leading-code an "official charset".
66
67  ---------------------------------------------------------------------------
68  charset	dimension	 base leading-code	extended leading-code
69  ---------------------------------------------------------------------------
70  0x00		official dim1    -- none --		-- none --
71		(ASCII)
72  0x01..0x7F	--never used--
73  0x80		official dim1	 -- none --		-- none --
74		(eight-bit-graphic)
75  0x81..0x8F	official dim1    same as charset	-- none --
76  0x90..0x99	official dim2	 same as charset	-- none --
77  0x9A..0x9D	--never used--
78  0x9E		official dim1	 same as charset	-- none --
79		(eight-bit-control)
80  0x9F		--never used--
81  0xA0..0xDF	private dim1	    0x9A		same as charset
82		of 1-column width
83  0xE0..0xEF	private dim1	    0x9B		same as charset
84		of 2-column width
85  0xF0..0xF4	private dim2	    0x9C		same as charset
86		of 1-column width
87  0xF5..0xFE	private dim2	    0x9D		same as charset
88		of 2-column width
89  0xFF		--never used--
90  ---------------------------------------------------------------------------
91
92*/
93
94/* Definition of special leading-codes.  */
95/* Leading-code followed by extended leading-code.  */
96#define LEADING_CODE_PRIVATE_11	0x9A /* for private DIMENSION1 of 1-column */
97#define LEADING_CODE_PRIVATE_12	0x9B /* for private DIMENSION1 of 2-column */
98#define LEADING_CODE_PRIVATE_21	0x9C /* for private DIMENSION2 of 1-column */
99#define LEADING_CODE_PRIVATE_22	0x9D /* for private DIMENSION2 of 2-column */
100
101#define LEADING_CODE_8_BIT_CONTROL 0x9E /* for `eight-bit-control' */
102
103/* Extended leading-code.  */
104/* Start of each extended leading-codes.  */
105#define LEADING_CODE_EXT_11 0xA0 /* follows LEADING_CODE_PRIVATE_11 */
106#define LEADING_CODE_EXT_12 0xE0 /* follows LEADING_CODE_PRIVATE_12 */
107#define LEADING_CODE_EXT_21 0xF0 /* follows LEADING_CODE_PRIVATE_21 */
108#define LEADING_CODE_EXT_22 0xF5 /* follows LEADING_CODE_PRIVATE_22 */
109/* Maximum value of extended leading-codes.  */
110#define LEADING_CODE_EXT_MAX 0xFE
111
112/* Definition of minimum/maximum charset of each DIMENSION.  */
113#define MIN_CHARSET_OFFICIAL_DIMENSION1	0x80
114#define MAX_CHARSET_OFFICIAL_DIMENSION1	0x8F
115#define MIN_CHARSET_OFFICIAL_DIMENSION2	0x90
116#define MAX_CHARSET_OFFICIAL_DIMENSION2 0x99
117#define MIN_CHARSET_PRIVATE_DIMENSION1	LEADING_CODE_EXT_11
118#define MIN_CHARSET_PRIVATE_DIMENSION2	LEADING_CODE_EXT_21
119
120/* Maximum value of overall charset identification number.  */
121#define MAX_CHARSET 0xFE
122
123/* Definition of special charsets.  */
124#define CHARSET_ASCII		0	/* 0x00..0x7F */
125#define CHARSET_8_BIT_CONTROL	0x9E	/* 0x80..0x9F */
126#define CHARSET_8_BIT_GRAPHIC	0x80	/* 0xA0..0xFF */
127
128extern int charset_latin_iso8859_1; /* ISO8859-1 (Latin-1) */
129extern int charset_jisx0208_1978; /* JISX0208.1978 (Japanese Kanji old set) */
130extern int charset_jisx0208;	/* JISX0208.1983 (Japanese Kanji) */
131extern int charset_katakana_jisx0201; /* JISX0201.Kana (Japanese Katakana) */
132extern int charset_latin_jisx0201; /* JISX0201.Roman (Japanese Roman) */
133extern int charset_big5_1;	/* Big5 Level 1 (Chinese Traditional) */
134extern int charset_big5_2;	/* Big5 Level 2 (Chinese Traditional) */
135extern int charset_mule_unicode_0100_24ff;
136extern int charset_mule_unicode_2500_33ff;
137extern int charset_mule_unicode_e000_ffff;
138
139/* Check if CH is an ASCII character or a base leading-code.
140   Nowadays, any byte can be the first byte of a character in a
141   multibyte buffer/string.  So this macro name is not appropriate.  */
142#define CHAR_HEAD_P(ch) ((unsigned char) (ch) < 0xA0)
143
144/*** GENERAL NOTE on CHARACTER REPRESENTATION ***
145
146  Firstly, the term "character" or "char" is used for a multilingual
147  character (of course, including ASCII characters), not for a byte in
148  computer memory.  We use the term "code" or "byte" for the latter
149  case.
150
151  A character is identified by charset and one or two POSITION-CODEs.
152  POSITION-CODE is the position of the character in the charset.  A
153  character of DIMENSION1 charset has one POSITION-CODE: POSITION-CODE-1.
154  A character of DIMENSION2 charset has two POSITION-CODE:
155  POSITION-CODE-1 and POSITION-CODE-2.  The code range of
156  POSITION-CODE is 0x20..0x7F.
157
158  Emacs has two kinds of representation of a character: multi-byte
159  form (for buffers and strings) and single-word form (for character
160  objects in Emacs Lisp).  The latter is called "character code"
161  hereafter.  Both representations encode the information of charset
162  and POSITION-CODE but in a different way (for instance, the MSB of
163  POSITION-CODE is set in multi-byte form).
164
165  For details of the multi-byte form, see the section "2. Emacs
166  internal format handlers" of `coding.c'.
167
168  Emacs uses 19 bits for a character code.  The bits are divided into
169  3 fields: FIELD1(5bits):FIELD2(7bits):FIELD3(7bits).
170
171  A character code of DIMENSION1 character uses FIELD2 to hold charset
172  and FIELD3 to hold POSITION-CODE-1.  A character code of DIMENSION2
173  character uses FIELD1 to hold charset, FIELD2 and FIELD3 to hold
174  POSITION-CODE-1 and POSITION-CODE-2 respectively.
175
176  More precisely...
177
178  FIELD2 of DIMENSION1 character (except for ascii, eight-bit-control,
179  and eight-bit-graphic) is "charset - 0x70".  This is to make all
180  character codes except for ASCII and 8-bit codes greater than 256.
181  So, the range of FIELD2 of DIMENSION1 character is 0, 1, or
182  0x11..0x7F.
183
184  FIELD1 of DIMENSION2 character is "charset - 0x8F" for official
185  charset and "charset - 0xE0" for private charset.  So, the range of
186  FIELD1 of DIMENSION2 character is 0x01..0x1E.
187
188  -----------------------------------------------------------------------------
189  charset		FIELD1 (5-bit)	    FIELD2 (7-bit)	FIELD3 (7-bit)
190  -----------------------------------------------------------------------------
191  ascii			0		    0			0x00..0x7F
192  eight-bit-control	0		    1			0x00..0x1F
193  eight-bit-graphic	0		    1			0x20..0x7F
194  DIMENSION1		0		    charset - 0x70	POSITION-CODE-1
195  DIMENSION2(o)		charset - 0x8F	    POSITION-CODE-1	POSITION-CODE-2
196  DIMENSION2(p)		charset - 0xE0	    POSITION-CODE-1	POSITION-CODE-2
197  -----------------------------------------------------------------------------
198  "(o)": official, "(p)": private
199  -----------------------------------------------------------------------------
200*/
201
202/* Masks of each field of character code.  */
203#define CHAR_FIELD1_MASK (0x1F << 14)
204#define CHAR_FIELD2_MASK (0x7F << 7)
205#define CHAR_FIELD3_MASK 0x7F
206
207/* Macros to access each field of character C.  */
208#define CHAR_FIELD1(c) (((c) & CHAR_FIELD1_MASK) >> 14)
209#define CHAR_FIELD2(c) (((c) & CHAR_FIELD2_MASK) >> 7)
210#define CHAR_FIELD3(c) ((c) & CHAR_FIELD3_MASK)
211
212/* Minimum character code of character of each DIMENSION.  */
213#define MIN_CHAR_OFFICIAL_DIMENSION1 \
214  ((0x81 - 0x70) << 7)
215#define MIN_CHAR_PRIVATE_DIMENSION1 \
216  ((MIN_CHARSET_PRIVATE_DIMENSION1 - 0x70) << 7)
217#define MIN_CHAR_OFFICIAL_DIMENSION2 \
218  ((MIN_CHARSET_OFFICIAL_DIMENSION2 - 0x8F) << 14)
219#define MIN_CHAR_PRIVATE_DIMENSION2 \
220  ((MIN_CHARSET_PRIVATE_DIMENSION2 - 0xE0) << 14)
221/* Maximum character code currently used plus 1.  */
222#define MAX_CHAR (0x1F << 14)
223
224/* 1 if C is a single byte character, else 0.  */
225#define SINGLE_BYTE_CHAR_P(c) (((unsigned)(c) & 0xFF) == (c))
226
227/* 1 if BYTE is an ASCII character in itself, in multibyte mode.  */
228#define ASCII_BYTE_P(byte) ((byte) < 0x80)
229
230/* A char-table containing information on each character set.
231
232   Unlike ordinary char-tables, this doesn't contain any nested tables.
233   Only the top level elements are used.  Each element is a vector of
234   the following information:
235	CHARSET-ID, BYTES, DIMENSION, CHARS, WIDTH, DIRECTION,
236	LEADING-CODE-BASE, LEADING-CODE-EXT,
237	ISO-FINAL-CHAR, ISO-GRAPHIC-PLANE,
238	REVERSE-CHARSET, SHORT-NAME, LONG-NAME,	DESCRIPTION,
239	PLIST.
240
241   CHARSET-ID (integer) is the identification number of the charset.
242
243   BYTES (integer) is the length of the multi-byte form of a character
244   in the charset: one of 1, 2, 3, and 4.
245
246   DIMENSION (integer) is the number of bytes to represent a character: 1 or 2.
247
248   CHARS (integer) is the number of characters in a dimension: 94 or 96.
249
250   WIDTH (integer) is the number of columns a character in the charset
251   occupies on the screen: one of 0, 1, and 2..
252
253   DIRECTION (integer) is the rendering direction of characters in the
254   charset when rendering.  If 0, render from left to right, else
255   render from right to left.
256
257   LEADING-CODE-BASE (integer) is the base leading-code for the
258   charset.
259
260   LEADING-CODE-EXT (integer) is the extended leading-code for the
261   charset.  All charsets of less than 0xA0 have the value 0.
262
263   ISO-FINAL-CHAR (character) is the final character of the
264   corresponding ISO 2022 charset.  It is -1 for such a character
265   that is used only internally (e.g. `eight-bit-control').
266
267   ISO-GRAPHIC-PLANE (integer) is the graphic plane to be invoked
268   while encoding to variants of ISO 2022 coding system, one of the
269   following: 0/graphic-plane-left(GL), 1/graphic-plane-right(GR).  It
270   is -1 for such a character that is used only internally
271   (e.g. `eight-bit-control').
272
273   REVERSE-CHARSET (integer) is the charset which differs only in
274   LEFT-TO-RIGHT value from the charset.  If there's no such a
275   charset, the value is -1.
276
277   SHORT-NAME (string) is the short name to refer to the charset.
278
279   LONG-NAME (string) is the long name to refer to the charset.
280
281   DESCRIPTION (string) is the description string of the charset.
282
283   PLIST (property list) may contain any type of information a user
284   wants to put and get by functions `put-charset-property' and
285   `get-charset-property' respectively.  */
286extern Lisp_Object Vcharset_table;
287
288/* Macros to access various information of CHARSET in Vcharset_table.
289   We provide these macros for efficiency.  No range check of CHARSET.  */
290
291/* Return entry of CHARSET (C integer) in Vcharset_table.  */
292#define CHARSET_TABLE_ENTRY(charset)					\
293  XCHAR_TABLE (Vcharset_table)->contents[((charset) == CHARSET_ASCII	\
294					  ? 0 : (charset) + 128)]
295
296/* Return information INFO-IDX of CHARSET.  */
297#define CHARSET_TABLE_INFO(charset, info_idx) \
298  XVECTOR (CHARSET_TABLE_ENTRY (charset))->contents[info_idx]
299
300#define CHARSET_ID_IDX (0)
301#define CHARSET_BYTES_IDX (1)
302#define CHARSET_DIMENSION_IDX (2)
303#define CHARSET_CHARS_IDX (3)
304#define CHARSET_WIDTH_IDX (4)
305#define CHARSET_DIRECTION_IDX (5)
306#define CHARSET_LEADING_CODE_BASE_IDX (6)
307#define CHARSET_LEADING_CODE_EXT_IDX (7)
308#define CHARSET_ISO_FINAL_CHAR_IDX (8)
309#define CHARSET_ISO_GRAPHIC_PLANE_IDX (9)
310#define CHARSET_REVERSE_CHARSET_IDX (10)
311#define CHARSET_SHORT_NAME_IDX (11)
312#define CHARSET_LONG_NAME_IDX (12)
313#define CHARSET_DESCRIPTION_IDX (13)
314#define CHARSET_PLIST_IDX (14)
315/* Size of a vector of each entry of Vcharset_table.  */
316#define CHARSET_MAX_IDX (15)
317
318/* And several more macros to be used frequently.  */
319#define CHARSET_BYTES(charset) \
320  XFASTINT (CHARSET_TABLE_INFO (charset, CHARSET_BYTES_IDX))
321#define CHARSET_DIMENSION(charset) \
322  XFASTINT (CHARSET_TABLE_INFO (charset, CHARSET_DIMENSION_IDX))
323#define CHARSET_CHARS(charset) \
324  XFASTINT (CHARSET_TABLE_INFO (charset, CHARSET_CHARS_IDX))
325#define CHARSET_WIDTH(charset) \
326  XFASTINT (CHARSET_TABLE_INFO (charset, CHARSET_WIDTH_IDX))
327#define CHARSET_DIRECTION(charset) \
328  XFASTINT (CHARSET_TABLE_INFO (charset, CHARSET_DIRECTION_IDX))
329#define CHARSET_LEADING_CODE_BASE(charset) \
330  XFASTINT (CHARSET_TABLE_INFO (charset, CHARSET_LEADING_CODE_BASE_IDX))
331#define CHARSET_LEADING_CODE_EXT(charset) \
332  XFASTINT (CHARSET_TABLE_INFO (charset, CHARSET_LEADING_CODE_EXT_IDX))
333#define CHARSET_ISO_FINAL_CHAR(charset) \
334  XINT (CHARSET_TABLE_INFO (charset, CHARSET_ISO_FINAL_CHAR_IDX))
335#define CHARSET_ISO_GRAPHIC_PLANE(charset) \
336  XINT (CHARSET_TABLE_INFO (charset, CHARSET_ISO_GRAPHIC_PLANE_IDX))
337#define CHARSET_REVERSE_CHARSET(charset) \
338  XINT (CHARSET_TABLE_INFO (charset, CHARSET_REVERSE_CHARSET_IDX))
339
340/* Macros to specify direction of a charset.  */
341#define CHARSET_DIRECTION_LEFT_TO_RIGHT 0
342#define CHARSET_DIRECTION_RIGHT_TO_LEFT 1
343
344/* A vector of charset symbol indexed by charset-id.  This is used
345   only for returning charset symbol from C functions.  */
346extern Lisp_Object Vcharset_symbol_table;
347
348/* Return symbol of CHARSET.  */
349#define CHARSET_SYMBOL(charset) \
350  XVECTOR (Vcharset_symbol_table)->contents[charset]
351
352/* 1 if CHARSET is in valid value range, else 0.  */
353#define CHARSET_VALID_P(charset)					 \
354  ((charset) == 0							 \
355   || ((charset) > 0x80 && (charset) <= MAX_CHARSET_OFFICIAL_DIMENSION2) \
356   || ((charset) >= MIN_CHARSET_PRIVATE_DIMENSION1			 \
357       && (charset) <= MAX_CHARSET)					 \
358   || ((charset) == CHARSET_8_BIT_CONTROL)				 \
359   || ((charset) == CHARSET_8_BIT_GRAPHIC))
360
361/* 1 if CHARSET is already defined, else 0.  */
362#define CHARSET_DEFINED_P(charset)			\
363  (((charset) >= 0) && ((charset) <= MAX_CHARSET)	\
364   && !NILP (CHARSET_TABLE_ENTRY (charset)))
365
366/* Since the information CHARSET-BYTES and CHARSET-WIDTH of
367   Vcharset_table can be retrieved only by the first byte of
368   multi-byte form (an ASCII code or a base leading-code), we provide
369   here tables to be used by macros BYTES_BY_CHAR_HEAD and
370   WIDTH_BY_CHAR_HEAD for faster information retrieval.  */
371extern int bytes_by_char_head[256];
372extern int width_by_char_head[256];
373
374#define BYTES_BY_CHAR_HEAD(char_head)	\
375  (ASCII_BYTE_P (char_head) ? 1 : bytes_by_char_head[char_head])
376#define WIDTH_BY_CHAR_HEAD(char_head)	\
377  (ASCII_BYTE_P (char_head) ? 1 : width_by_char_head[char_head])
378
379/* Charset of the character C.  */
380#define CHAR_CHARSET(c)							\
381  (SINGLE_BYTE_CHAR_P (c)						\
382   ? (ASCII_BYTE_P (c)							\
383      ? CHARSET_ASCII							\
384      : (c) < 0xA0 ? CHARSET_8_BIT_CONTROL : CHARSET_8_BIT_GRAPHIC)	\
385   : ((c) < MIN_CHAR_OFFICIAL_DIMENSION2				\
386      ? CHAR_FIELD2 (c) + 0x70						\
387      : ((c) < MIN_CHAR_PRIVATE_DIMENSION2				\
388	 ? CHAR_FIELD1 (c) + 0x8F					\
389	 : CHAR_FIELD1 (c) + 0xE0)))
390
391/* Check if two characters C1 and C2 belong to the same charset.  */
392#define SAME_CHARSET_P(c1, c2)				\
393  (c1 < MIN_CHAR_OFFICIAL_DIMENSION2			\
394   ? (c1 & CHAR_FIELD2_MASK) == (c2 & CHAR_FIELD2_MASK)	\
395   : (c1 & CHAR_FIELD1_MASK) == (c2 & CHAR_FIELD1_MASK))
396
397/* Return a character of which charset is CHARSET and position-codes
398   are C1 and C2.  DIMENSION1 character ignores C2.  */
399#define MAKE_CHAR(charset, c1, c2)					    \
400  ((charset) == CHARSET_ASCII						    \
401   ? (c1) & 0x7F							    \
402   : (((charset) == CHARSET_8_BIT_CONTROL				    \
403       || (charset) == CHARSET_8_BIT_GRAPHIC)				    \
404      ? ((c1) & 0x7F) | 0x80						    \
405      : ((CHARSET_DEFINED_P (charset)					    \
406	  ? CHARSET_DIMENSION (charset) == 1				    \
407	  : (charset) < MIN_CHARSET_PRIVATE_DIMENSION2)			    \
408	 ? (((charset) - 0x70) << 7) | ((c1) <= 0 ? 0 : ((c1) & 0x7F))	    \
409	 : ((((charset)							    \
410	      - ((charset) < MIN_CHARSET_PRIVATE_DIMENSION2 ? 0x8F : 0xE0)) \
411	     << 14)							    \
412	    | ((c2) <= 0 ? 0 : ((c2) & 0x7F))				    \
413	    | ((c1) <= 0 ? 0 : (((c1) & 0x7F) << 7))))))
414
415
416/* If GENERICP is nonzero, return nonzero iff C is a valid normal or
417   generic character.  If GENERICP is zero, return nonzero iff C is a
418   valid normal character.  */
419#define CHAR_VALID_P(c, genericp)	\
420  ((c) >= 0				\
421   && (SINGLE_BYTE_CHAR_P (c) || char_valid_p (c, genericp)))
422
423/* This default value is used when nonascii-translation-table or
424   nonascii-insert-offset fail to convert unibyte character to a valid
425   multibyte character.  This makes a Latin-1 character.  */
426
427#define DEFAULT_NONASCII_INSERT_OFFSET 0x800
428
429/* Parse multibyte string STR of length LENGTH and set BYTES to the
430   byte length of a character at STR.  */
431
432#ifdef BYTE_COMBINING_DEBUG
433
434#define PARSE_MULTIBYTE_SEQ(str, length, bytes)			\
435  do {								\
436    int i = 1;							\
437    while (i < (length) && ! CHAR_HEAD_P ((str)[i])) i++;	\
438    (bytes) = BYTES_BY_CHAR_HEAD ((str)[0]);			\
439    if ((bytes) > i)						\
440      abort ();							\
441  } while (0)
442
443#else  /* not BYTE_COMBINING_DEBUG */
444
445#define PARSE_MULTIBYTE_SEQ(str, length, bytes)	\
446  ((void)(length), (bytes) = BYTES_BY_CHAR_HEAD ((str)[0]))
447
448#endif /* not BYTE_COMBINING_DEBUG */
449
450#define VALID_LEADING_CODE_P(code)	\
451  (! NILP (CHARSET_TABLE_ENTRY (code)))
452
453/* Return 1 iff the byte sequence at unibyte string STR (LENGTH bytes)
454   is valid as a multibyte form.  If valid, by a side effect, BYTES is
455   set to the byte length of the multibyte form.  */
456
457#define UNIBYTE_STR_AS_MULTIBYTE_P(str, length, bytes)		\
458  (((str)[0] < 0x80 || (str)[0] >= 0xA0)			\
459   ? ((bytes) = 1)						\
460   : (((bytes) = BYTES_BY_CHAR_HEAD ((str)[0])),		\
461      ((bytes) <= (length)					\
462       && !CHAR_HEAD_P ((str)[1])				\
463       && ((bytes) == 2						\
464	   ? (str)[0] != LEADING_CODE_8_BIT_CONTROL		\
465	   : (!CHAR_HEAD_P ((str)[2])				\
466	      && ((bytes) == 3					\
467		  ? (((str)[0] != LEADING_CODE_PRIVATE_11	\
468		      && (str)[0] != LEADING_CODE_PRIVATE_12)	\
469		     || VALID_LEADING_CODE_P (str[1]))		\
470		  : (!CHAR_HEAD_P ((str)[3])			\
471		     && VALID_LEADING_CODE_P (str[1]))))))))
472
473
474/* Return 1 iff the byte sequence at multibyte string STR is valid as
475   a unibyte form.  By a side effect, BYTES is set to the byte length
476   of one character at STR.  */
477
478#define MULTIBYTE_STR_AS_UNIBYTE_P(str, bytes)	\
479  ((bytes) = BYTES_BY_CHAR_HEAD ((str)[0]),	\
480   (str)[0] != LEADING_CODE_8_BIT_CONTROL)
481
482/* The charset of character C is stored in CHARSET, and the
483   position-codes of C are stored in C1 and C2.
484   We store -1 in C2 if the dimension of the charset is 1.  */
485
486#define SPLIT_CHAR(c, charset, c1, c2)					    \
487  (SINGLE_BYTE_CHAR_P (c)						    \
488   ? ((charset								    \
489       = (ASCII_BYTE_P (c)						    \
490	  ? CHARSET_ASCII						    \
491	  : ((c) < 0xA0 ? CHARSET_8_BIT_CONTROL : CHARSET_8_BIT_GRAPHIC))), \
492      c1 = (c), c2 = -1)						    \
493   : ((c) & CHAR_FIELD1_MASK						    \
494      ? (charset = (CHAR_FIELD1 (c)					    \
495		    + ((c) < MIN_CHAR_PRIVATE_DIMENSION2 ? 0x8F : 0xE0)),   \
496	 c1 = CHAR_FIELD2 (c),						    \
497	 c2 = CHAR_FIELD3 (c))						    \
498      : (charset = CHAR_FIELD2 (c) + 0x70,				    \
499	 c1 = CHAR_FIELD3 (c),						    \
500	 c2 = -1)))
501
502/* Return 1 iff character C has valid printable glyph.  */
503#define CHAR_PRINTABLE_P(c) (ASCII_BYTE_P (c) || char_printable_p (c))
504
505/* The charset of the character at STR is stored in CHARSET, and the
506   position-codes are stored in C1 and C2.
507   We store -1 in C2 if the character is just 2 bytes.  */
508
509#define SPLIT_STRING(str, len, charset, c1, c2)			\
510  ((BYTES_BY_CHAR_HEAD ((unsigned char) *(str)) < 2		\
511    || BYTES_BY_CHAR_HEAD ((unsigned char) *(str)) > len	\
512    || split_string (str, len, &charset, &c1, &c2) < 0)		\
513   ? c1 = *(str), charset = CHARSET_ASCII			\
514   : charset)
515
516/* Mapping table from ISO2022's charset (specified by DIMENSION,
517   CHARS, and FINAL_CHAR) to Emacs' charset.  Should be accessed by
518   macro ISO_CHARSET_TABLE (DIMENSION, CHARS, FINAL_CHAR).  */
519extern int iso_charset_table[2][2][128];
520
521#define ISO_CHARSET_TABLE(dimension, chars, final_char) \
522  iso_charset_table[XINT (dimension) - 1][XINT (chars) > 94][XINT (final_char)]
523
524#define BASE_LEADING_CODE_P(c) (BYTES_BY_CHAR_HEAD ((unsigned char) (c)) > 1)
525
526/* Return how many bytes C will occupy in a multibyte buffer.  */
527#define CHAR_BYTES(c)					\
528  (SINGLE_BYTE_CHAR_P (c)				\
529   ? ((ASCII_BYTE_P (c) || (c) >= 0xA0) ? 1 : 2)	\
530   : char_bytes (c))
531
532/* The following two macros CHAR_STRING and STRING_CHAR are the main
533   entry points to convert between Emacs's two types of character
534   representations: multi-byte form and single-word form (character
535   code).  */
536
537/* Store multi-byte form of the character C in STR.  The caller should
538   allocate at least MAX_MULTIBYTE_LENGTH bytes area at STR in
539   advance.  Returns the length of the multi-byte form.  If C is an
540   invalid character code, signal an error.  */
541
542#define CHAR_STRING(c, str)						  \
543  (SINGLE_BYTE_CHAR_P (c)						  \
544   ? ((ASCII_BYTE_P (c) || c >= 0xA0)			  \
545      ? (*(str) = (unsigned char)(c), 1)				  \
546      : (*(str) = LEADING_CODE_8_BIT_CONTROL, *((str)+ 1) = c + 0x20, 2)) \
547   : char_to_string (c, (unsigned char *) str))
548
549/* Like CHAR_STRING but don't signal an error if C is invalid.
550   Value is -1 in this case.  */
551
552#define CHAR_STRING_NO_SIGNAL(c, str)					  \
553  (SINGLE_BYTE_CHAR_P (c)						  \
554   ? ((ASCII_BYTE_P (c) || c >= 0xA0)					  \
555      ? (*(str) = (unsigned char)(c), 1)				  \
556      : (*(str) = LEADING_CODE_8_BIT_CONTROL, *((str)+ 1) = c + 0x20, 2)) \
557   : char_to_string_1 (c, (unsigned char *) str))
558
559/* Return a character code of the character of which multi-byte form
560   is at STR and the length is LEN.  If STR doesn't contain valid
561   multi-byte form, only the first byte in STR is returned.  */
562
563#define STRING_CHAR(str, len)				\
564  (BYTES_BY_CHAR_HEAD ((unsigned char) *(str)) == 1	\
565   ? (unsigned char) *(str)				\
566   : string_to_char (str, len, 0))
567
568/* This is like STRING_CHAR but the third arg ACTUAL_LEN is set to the
569   length of the multi-byte form.  Just to know the length, use
570   MULTIBYTE_FORM_LENGTH.  */
571
572#define STRING_CHAR_AND_LENGTH(str, len, actual_len)	\
573  (BYTES_BY_CHAR_HEAD ((unsigned char) *(str)) == 1	\
574   ? ((actual_len) = 1), (unsigned char) *(str)		\
575   : string_to_char (str, len, &(actual_len)))
576
577/* Fetch the "next" character from Lisp string STRING at byte position
578   BYTEIDX, character position CHARIDX.  Store it into OUTPUT.
579
580   All the args must be side-effect-free.
581   BYTEIDX and CHARIDX must be lvalues;
582   we increment them past the character fetched.  */
583
584#define FETCH_STRING_CHAR_ADVANCE(OUTPUT, STRING, CHARIDX, BYTEIDX)	   \
585if (1)									   \
586  {									   \
587    CHARIDX++;								   \
588    if (STRING_MULTIBYTE (STRING))					   \
589      {									   \
590	const unsigned char *ptr = SDATA (STRING) + BYTEIDX;		   \
591	int space_left = SBYTES (STRING) - BYTEIDX;			   \
592	int actual_len;							   \
593									   \
594	OUTPUT = STRING_CHAR_AND_LENGTH (ptr, space_left, actual_len);	   \
595	BYTEIDX += actual_len;						   \
596      }									   \
597    else								   \
598      OUTPUT = SREF (STRING, BYTEIDX++);				   \
599  }									   \
600else
601
602/* Like FETCH_STRING_CHAR_ADVANCE but assume STRING is multibyte.  */
603
604#define FETCH_STRING_CHAR_ADVANCE_NO_CHECK(OUTPUT, STRING, CHARIDX, BYTEIDX)  \
605if (1)									      \
606  {									      \
607    const unsigned char *fetch_string_char_ptr = SDATA (STRING) + BYTEIDX;    \
608    int fetch_string_char_space_left = SBYTES (STRING) - BYTEIDX;	      \
609    int actual_len;							      \
610    									      \
611    OUTPUT								      \
612      = STRING_CHAR_AND_LENGTH (fetch_string_char_ptr,			      \
613			        fetch_string_char_space_left, actual_len);    \
614									      \
615    BYTEIDX += actual_len;						      \
616    CHARIDX++;								      \
617  }									      \
618else
619
620/* Like FETCH_STRING_CHAR_ADVANCE but fetch character from the current
621   buffer.  */
622
623#define FETCH_CHAR_ADVANCE(OUTPUT, CHARIDX, BYTEIDX)			  \
624if (1)									  \
625  {									  \
626    CHARIDX++;								  \
627    if (!NILP (current_buffer->enable_multibyte_characters))		  \
628      {									  \
629	unsigned char *ptr = BYTE_POS_ADDR (BYTEIDX);			  \
630	int space_left = ((CHARIDX < GPT ? GPT_BYTE : Z_BYTE) - BYTEIDX); \
631	int actual_len;							  \
632									  \
633	OUTPUT= STRING_CHAR_AND_LENGTH (ptr, space_left, actual_len);	  \
634	BYTEIDX += actual_len;						  \
635      }									  \
636    else								  \
637      {									  \
638	OUTPUT = *(BYTE_POS_ADDR (BYTEIDX));				  \
639	BYTEIDX++;							  \
640      }									  \
641  }									  \
642else
643
644/* Return the length of the multi-byte form at string STR of length LEN.  */
645
646#define MULTIBYTE_FORM_LENGTH(str, len)			\
647  (BYTES_BY_CHAR_HEAD (*(unsigned char *)(str)) == 1	\
648   ? 1							\
649   : multibyte_form_length (str, len))
650
651/* If P is before LIMIT, advance P to the next character boundary.  It
652   assumes that P is already at a character boundary of the sane
653   mulitbyte form whose end address is LIMIT.  */
654
655#define NEXT_CHAR_BOUNDARY(p, limit)	\
656  do {					\
657    if ((p) < (limit))			\
658      (p) += BYTES_BY_CHAR_HEAD (*(p));	\
659  } while (0)
660
661
662/* If P is after LIMIT, advance P to the previous character boundary.  */
663
664#define PREV_CHAR_BOUNDARY(p, limit)					\
665  do {									\
666    if ((p) > (limit))							\
667      {									\
668	const unsigned char *p0 = (p);					\
669	const unsigned char *p_limit = max (limit, p0 - MAX_MULTIBYTE_LENGTH);\
670	do {								\
671	  p0--;								\
672	} while (p0 >= p_limit && ! CHAR_HEAD_P (*p0));			\
673	/* If BBCH(*p0) > p-p0, it means we were not on a boundary.  */	\
674	(p) = (BYTES_BY_CHAR_HEAD (*p0) >= (p) - p0) ? p0 : (p) - 1;	\
675      }									\
676  } while (0)
677
678#define AT_CHAR_BOUNDARY_P(result, p, limit)	\
679  do {						\
680    if (CHAR_HEAD_P (*(p)) || (p) <= limit)	\
681      /* Optimization for the common case. */	\
682      (result) = 1;				\
683    else					\
684      {						\
685	const unsigned char *p_aux = (p)+1;	\
686	PREV_CHAR_BOUNDARY (p_aux, limit);	\
687	(result) = (p_aux == (p));		\
688      }						\
689} while (0)
690
691#ifdef emacs
692
693/* Increase the buffer byte position POS_BYTE of the current buffer to
694   the next character boundary.  This macro relies on the fact that
695   *GPT_ADDR and *Z_ADDR are always accessible and the values are
696   '\0'.  No range checking of POS.  */
697
698#ifdef BYTE_COMBINING_DEBUG
699
700#define INC_POS(pos_byte)				\
701  do {							\
702    unsigned char *p = BYTE_POS_ADDR (pos_byte);	\
703    if (BASE_LEADING_CODE_P (*p))			\
704      {							\
705	int len, bytes;					\
706	len = Z_BYTE - pos_byte;			\
707	PARSE_MULTIBYTE_SEQ (p, len, bytes);		\
708	pos_byte += bytes;				\
709      }							\
710    else						\
711      pos_byte++;					\
712  } while (0)
713
714#else  /* not BYTE_COMBINING_DEBUG */
715
716#define INC_POS(pos_byte)				\
717  do {							\
718    unsigned char *p = BYTE_POS_ADDR (pos_byte);	\
719    pos_byte += BYTES_BY_CHAR_HEAD (*p);		\
720  } while (0)
721
722#endif /* not BYTE_COMBINING_DEBUG */
723
724/* Decrease the buffer byte position POS_BYTE of the current buffer to
725   the previous character boundary.  No range checking of POS.  */
726#define DEC_POS(pos_byte)						\
727  do {									\
728    unsigned char *p, *p_min;						\
729    									\
730    pos_byte--;								\
731    if (pos_byte < GPT_BYTE)						\
732      p = BEG_ADDR + pos_byte - BEG_BYTE, p_min = BEG_ADDR;		\
733    else								\
734      p = BEG_ADDR + GAP_SIZE + pos_byte - BEG_BYTE, p_min = GAP_END_ADDR;\
735    if (p > p_min && !CHAR_HEAD_P (*p))					\
736      {									\
737	unsigned char *pend = p--;					\
738	int len, bytes;							\
739        if (p_min < p - MAX_MULTIBYTE_LENGTH)				\
740          p_min = p - MAX_MULTIBYTE_LENGTH;				\
741	while (p > p_min && !CHAR_HEAD_P (*p)) p--;			\
742	len = pend + 1 - p;						\
743	PARSE_MULTIBYTE_SEQ (p, len, bytes);				\
744	if (bytes == len)						\
745	  pos_byte -= len - 1;						\
746      }									\
747  } while (0)
748
749/* Increment both CHARPOS and BYTEPOS, each in the appropriate way.  */
750
751#define INC_BOTH(charpos, bytepos)				\
752do								\
753  {								\
754    (charpos)++;						\
755    if (NILP (current_buffer->enable_multibyte_characters))	\
756      (bytepos)++;						\
757    else							\
758      INC_POS ((bytepos));					\
759  }								\
760while (0)
761
762/* Decrement both CHARPOS and BYTEPOS, each in the appropriate way.  */
763
764#define DEC_BOTH(charpos, bytepos)				\
765do								\
766  {								\
767    (charpos)--;						\
768    if (NILP (current_buffer->enable_multibyte_characters))	\
769      (bytepos)--;						\
770    else							\
771      DEC_POS ((bytepos));					\
772  }								\
773while (0)
774
775/* Increase the buffer byte position POS_BYTE of the current buffer to
776   the next character boundary.  This macro relies on the fact that
777   *GPT_ADDR and *Z_ADDR are always accessible and the values are
778   '\0'.  No range checking of POS_BYTE.  */
779
780#ifdef BYTE_COMBINING_DEBUG
781
782#define BUF_INC_POS(buf, pos_byte)				\
783  do {								\
784    unsigned char *p = BUF_BYTE_ADDRESS (buf, pos_byte);	\
785    if (BASE_LEADING_CODE_P (*p))				\
786      {								\
787	int len, bytes;						\
788	len = BUF_Z_BYTE (buf) - pos_byte;			\
789	PARSE_MULTIBYTE_SEQ (p, len, bytes);			\
790	pos_byte += bytes;					\
791      }								\
792    else							\
793      pos_byte++;						\
794  } while (0)
795
796#else  /* not BYTE_COMBINING_DEBUG */
797
798#define BUF_INC_POS(buf, pos_byte)				\
799  do {								\
800    unsigned char *p = BUF_BYTE_ADDRESS (buf, pos_byte);	\
801    pos_byte += BYTES_BY_CHAR_HEAD (*p);			\
802  } while (0)
803
804#endif /* not BYTE_COMBINING_DEBUG */
805
806/* Decrease the buffer byte position POS_BYTE of the current buffer to
807   the previous character boundary.  No range checking of POS_BYTE.  */
808#define BUF_DEC_POS(buf, pos_byte)					\
809  do {									\
810    unsigned char *p, *p_min;						\
811    pos_byte--;								\
812    if (pos_byte < BUF_GPT_BYTE (buf))					\
813      {									\
814	p = BUF_BEG_ADDR (buf) + pos_byte - BEG_BYTE;			\
815	p_min = BUF_BEG_ADDR (buf);					\
816      }									\
817    else								\
818      {									\
819	p = BUF_BEG_ADDR (buf) + BUF_GAP_SIZE (buf) + pos_byte - BEG_BYTE;\
820	p_min = BUF_GAP_END_ADDR (buf);					\
821      }									\
822    if (p > p_min && !CHAR_HEAD_P (*p))					\
823      {									\
824	unsigned char *pend = p--;					\
825	int len, bytes;							\
826        if (p_min < p - MAX_MULTIBYTE_LENGTH)				\
827          p_min = p - MAX_MULTIBYTE_LENGTH;				\
828	while (p > p_min && !CHAR_HEAD_P (*p)) p--;			\
829	len = pend + 1 - p;						\
830	PARSE_MULTIBYTE_SEQ (p, len, bytes);				\
831	if (bytes == len)						\
832	  pos_byte -= len - 1;						\
833      }									\
834  } while (0)
835
836#endif /* emacs */
837
838/* This is the maximum byte length of multi-byte sequence.  */
839#define MAX_MULTIBYTE_LENGTH 4
840
841extern void invalid_character P_ ((int)) NO_RETURN;
842
843extern int translate_char P_ ((Lisp_Object, int, int, int, int));
844extern int split_string P_ ((const unsigned char *, int, int *,
845				       unsigned char *, unsigned char *));
846extern int char_to_string P_ ((int, unsigned char *));
847extern int char_to_string_1 P_ ((int, unsigned char *));
848extern int string_to_char P_ ((const unsigned char *, int, int *));
849extern int char_printable_p P_ ((int c));
850extern int multibyte_form_length P_ ((const unsigned char *, int));
851extern void parse_str_as_multibyte P_ ((const unsigned char *, int, int *,
852					int *));
853extern int str_as_multibyte P_ ((unsigned char *, int, int, int *));
854extern int parse_str_to_multibyte P_ ((unsigned char *, int));
855extern int str_to_multibyte P_ ((unsigned char *, int, int));
856extern int str_as_unibyte P_ ((unsigned char *, int));
857extern int get_charset_id P_ ((Lisp_Object));
858extern int find_charset_in_text P_ ((const unsigned char *, int, int, int *,
859				    Lisp_Object));
860extern int strwidth P_ ((unsigned char *, int));
861extern int c_string_width P_ ((const unsigned char *, int, int, int *, int *));
862extern int lisp_string_width P_ ((Lisp_Object, int, int *, int *));
863extern int char_bytes P_ ((int));
864extern int char_valid_p P_ ((int, int));
865
866EXFUN (Funibyte_char_to_multibyte, 1);
867
868extern Lisp_Object Vtranslation_table_vector;
869
870/* Return a translation table of id number ID.  */
871#define GET_TRANSLATION_TABLE(id) \
872  (XCDR(XVECTOR(Vtranslation_table_vector)->contents[(id)]))
873
874/* A char-table for characters which may invoke auto-filling.  */
875extern Lisp_Object Vauto_fill_chars;
876
877/* Copy LEN bytes from FROM to TO.  This macro should be used only
878   when a caller knows that LEN is short and the obvious copy loop is
879   faster than calling bcopy which has some overhead.  Copying a
880   multibyte sequence of a multibyte character is the typical case.  */
881
882#define BCOPY_SHORT(from, to, len)		\
883  do {						\
884    int i = len;				\
885    const unsigned char *from_p = from;		\
886    unsigned char *to_p = to;			\
887    while (i--) *to_p++ = *from_p++;		\
888  } while (0)
889
890#endif /* EMACS_CHARSET_H */
891
892/* arch-tag: 3b96db55-4961-481d-ac3e-219f46a2b3aa
893   (do not change this comment) */
894