1/* Header for coding system 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_CODING_H
27#define EMACS_CODING_H
28
29#include "ccl.h"
30
31/*** EMACS' INTERNAL FORMAT (emacs-mule) section ***/
32
33/* All code (1-byte) of Emacs' internal format is classified into one
34   of the followings.  See also `charset.h'.  */
35enum emacs_code_class_type
36  {
37    EMACS_control_code,		/* Control codes in the range
38				   0x00..0x1F and 0x7F except for the
39				   following two codes.  */
40    EMACS_linefeed_code,	/* 0x0A (linefeed) to denote
41				   end-of-line.  */
42    EMACS_carriage_return_code,	/* 0x0D (carriage-return) to be used
43				   in selective display mode.  */
44    EMACS_ascii_code,		/* ASCII characters.  */
45    EMACS_leading_code_2,	/* Base leading code of official
46				   TYPE9N character.  */
47    EMACS_leading_code_3,	/* Base leading code of private TYPE9N
48				   or official TYPE9Nx9N character.  */
49    EMACS_leading_code_4,	/* Base leading code of private
50				   TYPE9Nx9N character.  */
51    EMACS_invalid_code		/* Invalid code, i.e. a base leading
52				   code not yet assigned to any
53				   charset, or a code of the range
54				   0xA0..0xFF.  */
55  };
56
57extern enum emacs_code_class_type emacs_code_class[256];
58
59/*** ISO2022 section ***/
60
61/* Macros to define code of control characters for ISO2022's functions.  */
62			/* code */	/* function */
63#define ISO_CODE_LF	0x0A		/* line-feed */
64#define ISO_CODE_CR	0x0D		/* carriage-return */
65#define ISO_CODE_SO	0x0E		/* shift-out */
66#define ISO_CODE_SI	0x0F		/* shift-in */
67#define ISO_CODE_SS2_7	0x19		/* single-shift-2 for 7-bit code */
68#define ISO_CODE_ESC	0x1B		/* escape */
69#define ISO_CODE_SS2	0x8E		/* single-shift-2 */
70#define ISO_CODE_SS3	0x8F		/* single-shift-3 */
71#define ISO_CODE_CSI	0x9B		/* control-sequence-introduce */
72
73/* All code (1-byte) of ISO2022 is classified into one of the
74   followings.  */
75enum iso_code_class_type
76  {
77    ISO_control_0,		/* Control codes in the range
78				   0x00..0x1F and 0x7F, except for the
79				   following 5 codes.  */
80    ISO_carriage_return,	/* ISO_CODE_CR (0x0D) */
81    ISO_shift_out,		/* ISO_CODE_SO (0x0E) */
82    ISO_shift_in,		/* ISO_CODE_SI (0x0F) */
83    ISO_single_shift_2_7,	/* ISO_CODE_SS2_7 (0x19) */
84    ISO_escape,			/* ISO_CODE_SO (0x1B) */
85    ISO_control_1,		/* Control codes in the range
86				   0x80..0x9F, except for the
87				   following 3 codes.  */
88    ISO_single_shift_2,		/* ISO_CODE_SS2 (0x8E) */
89    ISO_single_shift_3,		/* ISO_CODE_SS3 (0x8F) */
90    ISO_control_sequence_introducer, /* ISO_CODE_CSI (0x9B) */
91    ISO_0x20_or_0x7F,		/* Codes of the values 0x20 or 0x7F.  */
92    ISO_graphic_plane_0,	/* Graphic codes in the range 0x21..0x7E.  */
93    ISO_0xA0_or_0xFF,		/* Codes of the values 0xA0 or 0xFF.  */
94    ISO_graphic_plane_1		/* Graphic codes in the range 0xA1..0xFE.  */
95  };
96
97/** The macros CODING_FLAG_ISO_XXX defines a flag bit of the `flags'
98  element in the structure `coding_system'.  This information is used
99  while encoding a text to ISO2022.  **/
100
101/* If set, produce short-form designation sequence (e.g. ESC $ A)
102   instead of long-form sequence (e.g. ESC $ ( A).  */
103#define CODING_FLAG_ISO_SHORT_FORM	0x0001
104
105/* If set, reset graphic planes and registers at end-of-line to the
106   initial state.  */
107#define CODING_FLAG_ISO_RESET_AT_EOL	0x0002
108
109/* If set, reset graphic planes and registers before any control
110   characters to the initial state.  */
111#define CODING_FLAG_ISO_RESET_AT_CNTL	0x0004
112
113/* If set, encode by 7-bit environment.  */
114#define CODING_FLAG_ISO_SEVEN_BITS	0x0008
115
116/* If set, use locking-shift function.  */
117#define CODING_FLAG_ISO_LOCKING_SHIFT	0x0010
118
119/* If set, use single-shift function.  Overwrite
120   CODING_FLAG_ISO_LOCKING_SHIFT.  */
121#define CODING_FLAG_ISO_SINGLE_SHIFT	0x0020
122
123/* If set, designate JISX0201-Roman instead of ASCII.  */
124#define CODING_FLAG_ISO_USE_ROMAN	0x0040
125
126/* If set, designate JISX0208-1978 instead of JISX0208-1983.  */
127#define CODING_FLAG_ISO_USE_OLDJIS	0x0080
128
129/* If set, do not produce ISO6429's direction specifying sequence.  */
130#define CODING_FLAG_ISO_NO_DIRECTION	0x0100
131
132/* If set, assume designation states are reset at beginning of line on
133   output.  */
134#define CODING_FLAG_ISO_INIT_AT_BOL	0x0200
135
136/* If set, designation sequence should be placed at beginning of line
137   on output.  */
138#define CODING_FLAG_ISO_DESIGNATE_AT_BOL 0x0400
139
140/* If set, do not encode unsafe characters on output.  */
141#define CODING_FLAG_ISO_SAFE		0x0800
142
143/* If set, extra latin codes (128..159) are accepted as a valid code
144   on input.  */
145#define CODING_FLAG_ISO_LATIN_EXTRA	0x1000
146
147/* If set, use designation escape sequence.  */
148#define CODING_FLAG_ISO_DESIGNATION	0x10000
149
150/* A character to be produced on output if encoding of the original
151   character is inhibitted by CODING_MODE_INHIBIT_UNENCODABLE_CHAR.
152   It must be an ASCII character.  */
153#define CODING_REPLACEMENT_CHARACTER '?'
154
155/* Structure of the field `spec.iso2022' in the structure `coding_system'.  */
156struct iso2022_spec
157{
158  /* The current graphic register invoked to each graphic plane.  */
159  int current_invocation[2];
160
161  /* The current charset designated to each graphic register.  */
162  int current_designation[4];
163
164  /* A charset initially designated to each graphic register.  */
165  int initial_designation[4];
166
167  /* If not -1, it is a graphic register specified in an invalid
168     designation sequence.  */
169  int last_invalid_designation_register;
170
171  /* A graphic register to which each charset should be designated.  */
172  unsigned char requested_designation[MAX_CHARSET + 1];
173
174  /* A revision number to be specified for each charset on encoding.
175     The value 255 means no revision number for the corresponding
176     charset.  */
177  unsigned char charset_revision_number[MAX_CHARSET + 1];
178
179  /* Set to 1 temporarily only when graphic register 2 or 3 is invoked
180     by single-shift while encoding.  */
181  int single_shifting;
182
183  /* Set to 1 temporarily only when processing at beginning of line.  */
184  int bol;
185};
186
187/* Macros to access each field in the structure `spec.iso2022'.  */
188#define CODING_SPEC_ISO_INVOCATION(coding, plane) \
189  (coding)->spec.iso2022.current_invocation[plane]
190#define CODING_SPEC_ISO_DESIGNATION(coding, reg) \
191  (coding)->spec.iso2022.current_designation[reg]
192#define CODING_SPEC_ISO_INITIAL_DESIGNATION(coding, reg) \
193  (coding)->spec.iso2022.initial_designation[reg]
194#define CODING_SPEC_ISO_REQUESTED_DESIGNATION(coding, charset) \
195  (coding)->spec.iso2022.requested_designation[charset]
196#define CODING_SPEC_ISO_REVISION_NUMBER(coding, charset) \
197  (coding)->spec.iso2022.charset_revision_number[charset]
198#define CODING_SPEC_ISO_SINGLE_SHIFTING(coding) \
199  (coding)->spec.iso2022.single_shifting
200#define CODING_SPEC_ISO_BOL(coding) \
201  (coding)->spec.iso2022.bol
202
203/* A value which may appear in
204   coding->spec.iso2022.requested_designation indicating that the
205   corresponding charset does not request any graphic register to be
206   designated.  */
207#define CODING_SPEC_ISO_NO_REQUESTED_DESIGNATION 4
208
209/* Return a charset which is currently designated to the graphic plane
210   PLANE in the coding-system CODING.  */
211#define CODING_SPEC_ISO_PLANE_CHARSET(coding, plane)	\
212  ((CODING_SPEC_ISO_INVOCATION (coding, plane) < 0)	\
213   ? -1							\
214   : CODING_SPEC_ISO_DESIGNATION (coding,		\
215				  CODING_SPEC_ISO_INVOCATION (coding, plane)))
216
217/*** BIG5 section ***/
218
219/* Macros to denote each type of BIG5 coding system.  */
220#define CODING_FLAG_BIG5_HKU	0x00 /* BIG5-HKU is one of variants of
221					BIG5 developed by Hong Kong
222					University.  */
223#define CODING_FLAG_BIG5_ETEN	0x01 /* BIG5_ETen is one of variants
224					of BIG5 developed by the
225					company ETen in Taiwan.  */
226
227/*** GENERAL section ***/
228
229/* Types of coding system.  */
230enum coding_type
231  {
232    coding_type_no_conversion,	/* A coding system which requires no
233				   conversion for reading and writing
234				   including end-of-line format.  */
235    coding_type_emacs_mule,	/* A coding system used in Emacs'
236				   buffer and string.  Requires no
237				   conversion for reading and writing
238				   except for end-of-line format.  */
239    coding_type_undecided,	/* A coding system which requires
240				   automatic detection of a real
241				   coding system.  */
242    coding_type_sjis,		/* SJIS coding system for Japanese.  */
243    coding_type_iso2022,	/* Any coding system of ISO2022
244				   variants.  */
245    coding_type_big5,		/* BIG5 coding system for Chinese.  */
246    coding_type_ccl,		/* The coding system of which decoder
247				   and encoder are written in CCL.  */
248    coding_type_raw_text	/* A coding system for a text
249				   containing random 8-bit code which
250				   does not require code conversion
251				   except for end-of-line format. */
252  };
253
254/* Formats of end-of-line.  */
255#define CODING_EOL_LF	0	/* Line-feed only, same as Emacs'
256				   internal format.  */
257#define CODING_EOL_CRLF	1	/* Sequence of carriage-return and
258				   line-feed.  */
259#define CODING_EOL_CR	2	/* Carriage-return only.  */
260#define CODING_EOL_UNDECIDED 3	/* This value is used to denote the
261				   eol-type is not yet decided.  */
262#define CODING_EOL_INCONSISTENT 4 /* This value is used to denote the
263				     eol-type is not consistent
264				     through the file.  */
265
266/* 1 iff composing.  */
267#define COMPOSING_P(coding) ((int) coding->composing > (int) COMPOSITION_NO)
268
269#define COMPOSITION_DATA_SIZE 4080
270#define COMPOSITION_DATA_MAX_BUNCH_LENGTH (4 + MAX_COMPOSITION_COMPONENTS*2)
271
272/* Data structure to hold information about compositions of text that
273   is being decoded or encode.  ISO 2022 base code conversion routines
274   handle special ESC sequences for composition specification.  But,
275   they can't get/put such information directly from/to a buffer in
276   the deepest place.  So, they store or retrieve the information
277   through this structure.
278
279   The encoder stores the information in this structure when it meets
280   ESC sequences for composition while encoding codes, then, after all
281   text codes are encoded, puts `composition' properties on the text
282   by referring to the structure.
283
284   The decoder at first stores the information of a text to be
285   decoded, then, while decoding codes, generates ESC sequences for
286   composition at proper places by referring to the structure.  */
287
288struct composition_data
289{
290  /* The character position of the first character to be encoded or
291     decoded.  START and END (see below) are relative to this
292     position.  */
293  int char_offset;
294
295  /* The composition data.  These elements are repeated for each
296     composition:
297	LENGTH START END METHOD [ COMPONENT ... ]
298     where,
299        LENGTH is the number of elements for this composition.
300
301	START and END are starting and ending character positions of
302	the composition relative to `char_offset'.
303
304	METHOD is one of `enum composing_status' specifying the way of
305	composition.
306
307	COMPONENT is a character or an encoded composition rule.  */
308  int data[COMPOSITION_DATA_SIZE];
309
310  /* The number of elements in `data' currently used.  */
311  int used;
312
313  /* Pointers to the previous and next structures.  When `data' is
314     filled up, another structure is allocated and linked in `next'.
315     The new structure has backward link to this structure in `prev'.
316     The number of chained structures depends on how many compositions
317     the text being encoded or decoded contains.  */
318  struct composition_data *prev, *next;
319};
320
321/* Macros used for the member `result' of the struct
322   coding_system.  */
323#define CODING_FINISH_NORMAL		0
324#define CODING_FINISH_INSUFFICIENT_SRC	1
325#define CODING_FINISH_INSUFFICIENT_DST	2
326#define CODING_FINISH_INCONSISTENT_EOL	3
327#define CODING_FINISH_INSUFFICIENT_CMP	4
328#define CODING_FINISH_INTERRUPT		5
329
330/* Macros used for the member `mode' of the struct coding_system.  */
331
332/* If set, recover the original CR or LF of the already decoded text
333   when the decoding routine encounters an inconsistent eol format.  */
334#define CODING_MODE_INHIBIT_INCONSISTENT_EOL	0x01
335
336/* If set, the decoding/encoding routines treat the current data as
337   the last block of the whole text to be converted, and do
338   appropriate finishing job.  */
339#define CODING_MODE_LAST_BLOCK			0x02
340
341/* If set, it means that the current source text is in a buffer which
342   enables selective display.  */
343#define CODING_MODE_SELECTIVE_DISPLAY		0x04
344
345/* If set, replace unencodabae characters by `?' on encoding.  */
346#define CODING_MODE_INHIBIT_UNENCODABLE_CHAR	0x08
347
348/* This flag is used by the decoding/encoding routines on the fly.  If
349   set, it means that right-to-left text is being processed.  */
350#define CODING_MODE_DIRECTION			0x10
351
352struct coding_system
353{
354  /* Type of the coding system.  */
355  enum coding_type type;
356
357  /* Type of end-of-line format (LF, CRLF, or CR) of the coding system.  */
358  int eol_type;
359
360  /* Flag bits of the coding system.  The meaning of each bit is common
361     to all types of coding systems.  */
362  unsigned int common_flags;
363
364  /* Flag bits of the coding system.  The meaning of each bit depends
365     on the type of the coding system.  */
366  unsigned int flags;
367
368  /* Mode bits of the coding system.  See the comments of the macros
369     CODING_MODE_XXX.  */
370  unsigned int mode;
371
372  /* The current status of composition handling.  */
373  int composing;
374
375  /* 1 iff the next character is a composition rule.  */
376  int composition_rule_follows;
377
378  /* Information of compositions are stored here on decoding and set
379     in advance on encoding.  */
380  struct composition_data *cmp_data;
381
382  /* Index to cmp_data->data for the first element for the current
383     composition.  */
384  int cmp_data_start;
385
386  /* Index to cmp_data->data for the current element for the current
387     composition.  */
388  int cmp_data_index;
389
390  /* Detailed information specific to each type of coding system.  */
391  union spec
392    {
393      struct iso2022_spec iso2022;
394      struct ccl_spec ccl;	/* Defined in ccl.h.  */
395    } spec;
396
397  /* Index number of coding category of the coding system.  */
398  int category_idx;
399
400  /* The following two members specify how characters 128..159 are
401     represented in source and destination text respectively.  1 means
402     they are represented by 2-byte sequence, 0 means they are
403     represented by 1-byte as is (see the comment in charset.h).  */
404  unsigned src_multibyte : 1;
405  unsigned dst_multibyte : 1;
406
407  /* How may heading bytes we can skip for decoding.  This is set to
408     -1 in setup_coding_system, and updated by detect_coding.  So,
409     when this is equal to the byte length of the text being
410     converted, we can skip the actual conversion process.  */
411  int heading_ascii;
412
413  /* The following members are set by encoding/decoding routine.  */
414  int produced, produced_char, consumed, consumed_char;
415
416  /* Number of error source data found in a decoding routine.  */
417  int errors;
418
419  /* Finish status of code conversion.  It should be one of macros
420     CODING_FINISH_XXXX.  */
421  int result;
422
423  /* If nonzero, suppress error notification.  */
424  int suppress_error;
425
426  /* The following members are all Lisp symbols.  We don't have to
427     protect them from GC because the current garbage collection
428     doesn't relocate Lisp symbols.  But, when it is changed, we must
429     find a way to protect them.  */
430
431  /* Backward pointer to the Lisp symbol of the coding system.  */
432  Lisp_Object symbol;
433
434  /* Lisp function (symbol) to be called after decoding to do
435     additional conversion, or nil.  */
436  Lisp_Object post_read_conversion;
437
438  /* Lisp function (symbol) to be called before encoding to do
439     additional conversion, or nil.  */
440  Lisp_Object pre_write_conversion;
441
442  /* Character translation tables to look up, or nil.  */
443  Lisp_Object translation_table_for_decode;
444  Lisp_Object translation_table_for_encode;
445};
446
447/* Mask bits for (struct coding_system *)->common_flags.  */
448#define CODING_REQUIRE_FLUSHING_MASK	0x01
449#define CODING_REQUIRE_DECODING_MASK	0x02
450#define CODING_REQUIRE_ENCODING_MASK	0x04
451#define CODING_REQUIRE_DETECTION_MASK	0x08
452#define CODING_ASCII_INCOMPATIBLE_MASK	0x10
453
454/* Return 1 if the coding system CODING requires specific code to be
455   attached at the tail of converted text.  */
456#define CODING_REQUIRE_FLUSHING(coding) \
457  ((coding)->common_flags & CODING_REQUIRE_FLUSHING_MASK)
458
459/* Return 1 if the coding system CODING requires code conversion on
460   decoding.  */
461#define CODING_REQUIRE_DECODING(coding)	\
462  ((coding)->dst_multibyte		\
463   || (coding)->common_flags & CODING_REQUIRE_DECODING_MASK)
464
465/* Return 1 if the coding system CODING requires code conversion on
466   encoding.
467   The non-multibyte part of the condition is to support encoding of
468   unibyte strings/buffers generated by string-as-unibyte or
469   (set-buffer-multibyte nil) from multibyte strings/buffers.  */
470#define CODING_REQUIRE_ENCODING(coding)	\
471  ((coding)->src_multibyte		\
472   || (coding)->common_flags & CODING_REQUIRE_ENCODING_MASK)
473
474/* Return 1 if the coding system CODING requires some kind of code
475   detection.  */
476#define CODING_REQUIRE_DETECTION(coding) \
477  ((coding)->common_flags & CODING_REQUIRE_DETECTION_MASK)
478
479/* Return 1 if the coding system CODING requires code conversion on
480   decoding or some kind of code detection.  */
481#define CODING_MAY_REQUIRE_DECODING(coding)	\
482  (CODING_REQUIRE_DECODING (coding)		\
483   || CODING_REQUIRE_DETECTION (coding))
484
485/* Index for each coding category in `coding_category_table' */
486#define CODING_CATEGORY_IDX_EMACS_MULE	0
487#define CODING_CATEGORY_IDX_SJIS	1
488#define CODING_CATEGORY_IDX_ISO_7	2
489#define CODING_CATEGORY_IDX_ISO_7_TIGHT	3
490#define CODING_CATEGORY_IDX_ISO_8_1	4
491#define CODING_CATEGORY_IDX_ISO_8_2	5
492#define CODING_CATEGORY_IDX_ISO_7_ELSE	6
493#define CODING_CATEGORY_IDX_ISO_8_ELSE	7
494#define CODING_CATEGORY_IDX_CCL		8
495#define CODING_CATEGORY_IDX_BIG5	9
496#define CODING_CATEGORY_IDX_UTF_8       10
497#define CODING_CATEGORY_IDX_UTF_16_BE   11
498#define CODING_CATEGORY_IDX_UTF_16_LE   12
499#define CODING_CATEGORY_IDX_RAW_TEXT	13
500#define CODING_CATEGORY_IDX_BINARY	14
501#define CODING_CATEGORY_IDX_MAX		15
502
503/* Definitions of flag bits returned by the function
504   detect_coding_mask ().  */
505#define CODING_CATEGORY_MASK_EMACS_MULE	(1 << CODING_CATEGORY_IDX_EMACS_MULE)
506#define CODING_CATEGORY_MASK_SJIS	(1 << CODING_CATEGORY_IDX_SJIS)
507#define CODING_CATEGORY_MASK_ISO_7	(1 << CODING_CATEGORY_IDX_ISO_7)
508#define CODING_CATEGORY_MASK_ISO_7_TIGHT (1 << CODING_CATEGORY_IDX_ISO_7_TIGHT)
509#define CODING_CATEGORY_MASK_ISO_8_1	(1 << CODING_CATEGORY_IDX_ISO_8_1)
510#define CODING_CATEGORY_MASK_ISO_8_2	(1 << CODING_CATEGORY_IDX_ISO_8_2)
511#define CODING_CATEGORY_MASK_ISO_7_ELSE	(1 << CODING_CATEGORY_IDX_ISO_7_ELSE)
512#define CODING_CATEGORY_MASK_ISO_8_ELSE	(1 << CODING_CATEGORY_IDX_ISO_8_ELSE)
513#define CODING_CATEGORY_MASK_CCL	(1 << CODING_CATEGORY_IDX_CCL)
514#define CODING_CATEGORY_MASK_BIG5	(1 << CODING_CATEGORY_IDX_BIG5)
515#define CODING_CATEGORY_MASK_UTF_8      (1 << CODING_CATEGORY_IDX_UTF_8)
516#define CODING_CATEGORY_MASK_UTF_16_BE  (1 << CODING_CATEGORY_IDX_UTF_16_BE)
517#define CODING_CATEGORY_MASK_UTF_16_LE  (1 << CODING_CATEGORY_IDX_UTF_16_LE)
518#define CODING_CATEGORY_MASK_RAW_TEXT	(1 << CODING_CATEGORY_IDX_RAW_TEXT)
519#define CODING_CATEGORY_MASK_BINARY	(1 << CODING_CATEGORY_IDX_BINARY)
520
521/* This value is returned if detect_coding_mask () find nothing other
522   than ASCII characters.  */
523#define CODING_CATEGORY_MASK_ANY  	\
524  (  CODING_CATEGORY_MASK_EMACS_MULE	\
525   | CODING_CATEGORY_MASK_SJIS	  	\
526   | CODING_CATEGORY_MASK_ISO_7	  	\
527   | CODING_CATEGORY_MASK_ISO_7_TIGHT  	\
528   | CODING_CATEGORY_MASK_ISO_8_1 	\
529   | CODING_CATEGORY_MASK_ISO_8_2 	\
530   | CODING_CATEGORY_MASK_ISO_7_ELSE	\
531   | CODING_CATEGORY_MASK_ISO_8_ELSE	\
532   | CODING_CATEGORY_MASK_CCL		\
533   | CODING_CATEGORY_MASK_BIG5		\
534   | CODING_CATEGORY_MASK_UTF_8		\
535   | CODING_CATEGORY_MASK_UTF_16_BE	\
536   | CODING_CATEGORY_MASK_UTF_16_LE)
537
538#define CODING_CATEGORY_MASK_ISO_7BIT \
539  (CODING_CATEGORY_MASK_ISO_7 | CODING_CATEGORY_MASK_ISO_7_TIGHT)
540
541#define CODING_CATEGORY_MASK_ISO_8BIT \
542  (CODING_CATEGORY_MASK_ISO_8_1 | CODING_CATEGORY_MASK_ISO_8_2)
543
544#define CODING_CATEGORY_MASK_ISO_SHIFT \
545  (CODING_CATEGORY_MASK_ISO_7_ELSE | CODING_CATEGORY_MASK_ISO_8_ELSE)
546
547#define CODING_CATEGORY_MASK_ISO	\
548  (  CODING_CATEGORY_MASK_ISO_7BIT	\
549   | CODING_CATEGORY_MASK_ISO_SHIFT	\
550   | CODING_CATEGORY_MASK_ISO_8BIT)
551
552#define CODING_CATEGORY_MASK_UTF_16_BE_LE \
553   (CODING_CATEGORY_MASK_UTF_16_BE | CODING_CATEGORY_MASK_UTF_16_LE)
554
555/* Macros to decode or encode a character of JISX0208 in SJIS.  S1 and
556   S2 are the 1st and 2nd position-codes of JISX0208 in SJIS coding
557   system.  C1 and C2 are the 1st and 2nd position codes of Emacs'
558   internal format.  */
559
560#define DECODE_SJIS(s1, s2, c1, c2)		  	\
561  do {						  	\
562    if (s2 >= 0x9F)				  	\
563      c1 = s1 * 2 - (s1 >= 0xE0 ? 0x160 : 0xE0),  	\
564      c2 = s2 - 0x7E;				  	\
565    else					  	\
566      c1 = s1 * 2 - ((s1 >= 0xE0) ? 0x161 : 0xE1),	\
567      c2 = s2 - ((s2 >= 0x7F) ? 0x20 : 0x1F);	  	\
568  } while (0)
569
570#define ENCODE_SJIS(c1, c2, s1, s2)			\
571  do {							\
572    if (c1 & 1)						\
573      s1 = c1 / 2 + ((c1 < 0x5F) ? 0x71 : 0xB1),	\
574      s2 = c2 + ((c2 >= 0x60) ? 0x20 : 0x1F);		\
575    else						\
576      s1 = c1 / 2 + ((c1 < 0x5F) ? 0x70 : 0xB0),	\
577      s2 = c2 + 0x7E;					\
578  } while (0)
579
580/* Encode the file name NAME using the specified coding system
581   for file names, if any.  */
582#define ENCODE_FILE(name)						   \
583  (! NILP (Vfile_name_coding_system)					   \
584   && !EQ (Vfile_name_coding_system, make_number (0))			   \
585   ? code_convert_string_norecord (name, Vfile_name_coding_system, 1)	   \
586   : (! NILP (Vdefault_file_name_coding_system)				   \
587      && !EQ (Vdefault_file_name_coding_system, make_number (0))	   \
588      ? code_convert_string_norecord (name, Vdefault_file_name_coding_system, 1) \
589      : name))
590
591/* Decode the file name NAME using the specified coding system
592   for file names, if any.  */
593#define DECODE_FILE(name)						   \
594  (! NILP (Vfile_name_coding_system)					   \
595   && !EQ (Vfile_name_coding_system, make_number (0))			   \
596   ? code_convert_string_norecord (name, Vfile_name_coding_system, 0)	   \
597   : (! NILP (Vdefault_file_name_coding_system)				   \
598      && !EQ (Vdefault_file_name_coding_system, make_number (0))	   \
599      ? code_convert_string_norecord (name, Vdefault_file_name_coding_system, 0) \
600      : name))
601
602/* Encode the string STR using the specified coding system
603   for system functions, if any.  */
604#define ENCODE_SYSTEM(str)						   \
605  (! NILP (Vlocale_coding_system)					   \
606   && !EQ (Vlocale_coding_system, make_number (0))			   \
607   ? code_convert_string_norecord (str, Vlocale_coding_system, 1)	   \
608   : str)
609
610/* Decode the string STR using the specified coding system
611   for system functions, if any.  */
612#define DECODE_SYSTEM(str)						   \
613  (! NILP (Vlocale_coding_system)					   \
614   && !EQ (Vlocale_coding_system, make_number (0))			   \
615   ? code_convert_string_norecord (str, Vlocale_coding_system, 0)	   \
616   : str)
617
618#define ENCODE_UTF_8(str) code_convert_string_norecord (str, Qutf_8, 1)
619
620/* Extern declarations.  */
621extern int decode_coding P_ ((struct coding_system *, const unsigned char *,
622			      unsigned char *, int, int));
623extern int encode_coding P_ ((struct coding_system *, const unsigned char *,
624			      unsigned char *, int, int));
625extern void coding_save_composition P_ ((struct coding_system *, int, int,
626					 Lisp_Object));
627extern void coding_free_composition_data P_ ((struct coding_system *));
628extern void coding_adjust_composition_offset P_ ((struct coding_system *,
629						  int));
630extern void coding_allocate_composition_data P_ ((struct coding_system *,
631						  int));
632extern void coding_restore_composition P_ ((struct coding_system *,
633					    Lisp_Object));
634extern int code_convert_region P_ ((int, int, int, int, struct coding_system *,
635				    int, int));
636extern Lisp_Object run_pre_post_conversion_on_str P_ ((Lisp_Object,
637						       struct coding_system *,
638						       int));
639extern void run_pre_write_conversin_on_c_str P_ ((unsigned char **, int *,
640						  int, int,
641						  struct coding_system *));
642
643extern int decoding_buffer_size P_ ((struct coding_system *, int));
644extern int encoding_buffer_size P_ ((struct coding_system *, int));
645extern void detect_coding P_ ((struct coding_system *, const unsigned char *,
646			       int));
647extern void detect_eol P_ ((struct coding_system *, const unsigned char *,
648			    int));
649extern int setup_coding_system P_ ((Lisp_Object, struct coding_system *));
650extern Lisp_Object code_convert_string P_ ((Lisp_Object,
651					    struct coding_system *, int, int));
652extern Lisp_Object code_convert_string1 P_ ((Lisp_Object, Lisp_Object,
653					     Lisp_Object, int));
654extern Lisp_Object code_convert_string_norecord P_ ((Lisp_Object, Lisp_Object,
655						     int));
656extern void setup_raw_text_coding_system P_ ((struct coding_system *));
657extern Lisp_Object encode_coding_string P_ ((Lisp_Object,
658					     struct coding_system *, int));
659extern Lisp_Object decode_coding_string P_ ((Lisp_Object,
660					     struct coding_system *, int));
661extern Lisp_Object Qcoding_system, Qeol_type, Qcoding_category_index;
662extern Lisp_Object Qraw_text, Qemacs_mule;
663extern Lisp_Object Qbuffer_file_coding_system;
664extern Lisp_Object Vcoding_category_list;
665extern Lisp_Object Qutf_8;
666
667extern Lisp_Object Qtranslation_table;
668extern Lisp_Object Qtranslation_table_id;
669
670/* Mnemonic strings to indicate each type of end-of-line.  */
671extern Lisp_Object eol_mnemonic_unix, eol_mnemonic_dos, eol_mnemonic_mac;
672/* Mnemonic string to indicate type of end-of-line is not yet decided.  */
673extern Lisp_Object eol_mnemonic_undecided;
674
675/* Format of end-of-line decided by system.  */
676extern int system_eol_type;
677
678#ifdef emacs
679extern Lisp_Object Qfile_coding_system;
680extern Lisp_Object Qcall_process, Qcall_process_region;
681extern Lisp_Object Qstart_process, Qopen_network_stream;
682extern Lisp_Object Qwrite_region;
683
684extern char *emacs_strerror P_ ((int));
685
686/* Coding-system for reading files and receiving data from process.  */
687extern Lisp_Object Vcoding_system_for_read;
688/* Coding-system for writing files and sending data to process.  */
689extern Lisp_Object Vcoding_system_for_write;
690/* Coding-system actually used in the latest I/O.  */
691extern Lisp_Object Vlast_coding_system_used;
692/* Coding-system to use with system messages (e.g. strerror).  */
693extern Lisp_Object Vlocale_coding_system;
694
695/* If non-zero, process buffer inherits the coding system used to decode
696   the subprocess output.  */
697extern int inherit_process_coding_system;
698
699/* Coding-system to be used for encoding terminal output.  This
700   structure contains information of a coding-system specified by the
701   function `set-terminal-coding-system'.  */
702extern struct coding_system terminal_coding;
703
704/* Coding system to be used to encode text for terminal display when
705   terminal coding system is nil.  */
706extern struct coding_system safe_terminal_coding;
707
708/* Coding-system of what is sent from terminal keyboard.  This
709   structure contains information of a coding-system specified by the
710   function `set-keyboard-coding-system'.  */
711extern struct coding_system keyboard_coding;
712
713/* Default coding system to be used to write a file.  */
714extern struct coding_system default_buffer_file_coding;
715
716/* Default coding systems used for process I/O.  */
717extern Lisp_Object Vdefault_process_coding_system;
718
719/* Function to call to force a user to force select a proper coding
720   system.  */
721extern Lisp_Object Vselect_safe_coding_system_function;
722
723/* If nonzero, on writing a file, Vselect_safe_coding_system_function
724   is called even if Vcoding_system_for_write is non-nil.  */
725extern int coding_system_require_warning;
726
727/* Coding system for file names, or nil if none.  */
728extern Lisp_Object Vfile_name_coding_system;
729
730/* Coding system for file names used only when
731   Vfile_name_coding_system is nil.  */
732extern Lisp_Object Vdefault_file_name_coding_system;
733
734#endif
735
736/* Error signaled when there's a problem with detecting coding system */
737extern Lisp_Object Qcoding_system_error;
738
739#endif /* EMACS_CODING_H */
740
741/* arch-tag: 2bc3b4fa-6870-4f64-8135-b962b2d290e4
742   (do not change this comment) */
743