src/coding.h

   1 /* Header for coding system handler.
   2    Copyright (C) 1995, 1997 Electrotechnical Laboratory, JAPAN.
   3    Licensed to the Free Software Foundation.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #ifndef EMACS_CODING_H
  23 #define EMACS_CODING_H
  24
  25 #include "ccl.h"
  26
  27 /*** EMACS' INTERNAL FORMAT (emacs-mule) section ***/
  28
  29 /* All code (1-byte) of Emacs' internal format is classified into one
  30    of the followings.  See also `charset.h'.  */
  31 enum emacs_code_class_type
  32   {
  33     EMACS_control_code,         /* Control codes in the range
  34                                    0x00..0x1F and 0x7F except for the
  35                                    following two codes.  */
  36     EMACS_linefeed_code,        /* 0x0A (linefeed) to denote
  37                                    end-of-line.  */
  38     EMACS_carriage_return_code, /* 0x0D (carriage-return) to be used
  39                                    in selective display mode.  */
  40     EMACS_ascii_code,           /* ASCII characters.  */
  41     EMACS_leading_code_2,       /* Base leading code of official
  42                                    TYPE9N character.  */
  43     EMACS_leading_code_3,       /* Base leading code of private TYPE9N
  44                                    or official TYPE9Nx9N character.  */
  45     EMACS_leading_code_4,       /* Base leading code of private
  46                                    TYPE9Nx9N character.  */
  47     EMACS_invalid_code          /* Invalid code, i.e. a base leading
  48                                    code not yet assigned to any
  49                                    charset, or a code of the range
  50                                    0xA0..0xFF.  */
  51   };
  52
  53 extern enum emacs_code_class_type emacs_code_class[256];
  54
  55 /*** ISO2022 section ***/
  56
  57 /* Macros to define code of control characters for ISO2022's functions.  */
  58                         /* code */      /* function */
  59 #define ISO_CODE_LF     0x0A            /* line-feed */
  60 #define ISO_CODE_CR     0x0D            /* carriage-return */
  61 #define ISO_CODE_SO     0x0E            /* shift-out */
  62 #define ISO_CODE_SI     0x0F            /* shift-in */
  63 #define ISO_CODE_SS2_7  0x19            /* single-shift-2 for 7-bit code */
  64 #define ISO_CODE_ESC    0x1B            /* escape */
  65 #define ISO_CODE_SS2    0x8E            /* single-shift-2 */
  66 #define ISO_CODE_SS3    0x8F            /* single-shift-3 */
  67 #define ISO_CODE_CSI    0x9B            /* control-sequence-introduce */
  68
  69 /* All code (1-byte) of ISO2022 is classified into one of the
  70    followings.  */
  71 enum iso_code_class_type
  72   {
  73     ISO_control_0,              /* Control codes in the range
  74                                    0x00..0x1F and 0x7F, except for the
  75                                    following 5 codes.  */
  76     ISO_carriage_return,        /* ISO_CODE_CR (0x0D) */
  77     ISO_shift_out,              /* ISO_CODE_SO (0x0E) */
  78     ISO_shift_in,               /* ISO_CODE_SI (0x0F) */
  79     ISO_single_shift_2_7,       /* ISO_CODE_SS2_7 (0x19) */
  80     ISO_escape,                 /* ISO_CODE_SO (0x1B) */
  81     ISO_control_1,              /* Control codes in the range
  82                                    0x80..0x9F, except for the
  83                                    following 3 codes.  */
  84     ISO_single_shift_2,         /* ISO_CODE_SS2 (0x8E) */
  85     ISO_single_shift_3,         /* ISO_CODE_SS3 (0x8F) */
  86     ISO_control_sequence_introducer, /* ISO_CODE_CSI (0x9B) */
  87     ISO_0x20_or_0x7F,           /* Codes of the values 0x20 or 0x7F.  */
  88     ISO_graphic_plane_0,        /* Graphic codes in the range 0x21..0x7E.  */
  89     ISO_0xA0_or_0xFF,           /* Codes of the values 0xA0 or 0xFF.  */
  90     ISO_graphic_plane_1         /* Graphic codes in the range 0xA1..0xFE.  */
  91   };
  92
  93 /** The macros CODING_FLAG_ISO_XXX defines a flag bit of the `flags'
  94   element in the structure `coding_system'.  This information is used
  95   while encoding a text to ISO2022.  **/
  96
  97 /* If set, produce short-form designation sequence (e.g. ESC $ A)
  98    instead of long-form sequence (e.g. ESC $ ( A).  */
  99 #define CODING_FLAG_ISO_SHORT_FORM      0x0001
 100
 101 /* If set, reset graphic planes and registers at end-of-line to the
 102    initial state.  */
 103 #define CODING_FLAG_ISO_RESET_AT_EOL    0x0002
 104
 105 /* If set, reset graphic planes and registers before any control
 106    characters to the initial state.  */
 107 #define CODING_FLAG_ISO_RESET_AT_CNTL   0x0004
 108
 109 /* If set, encode by 7-bit environment.  */
 110 #define CODING_FLAG_ISO_SEVEN_BITS      0x0008
 111
 112 /* If set, use locking-shift function.  */
 113 #define CODING_FLAG_ISO_LOCKING_SHIFT   0x0010
 114
 115 /* If set, use single-shift function.  Overwrite
 116    CODING_FLAG_ISO_LOCKING_SHIFT.  */
 117 #define CODING_FLAG_ISO_SINGLE_SHIFT    0x0020
 118
 119 /* If set, designate JISX0201-Roman instead of ASCII.  */
 120 #define CODING_FLAG_ISO_USE_ROMAN       0x0040
 121
 122 /* If set, designate JISX0208-1978 instead of JISX0208-1983.  */
 123 #define CODING_FLAG_ISO_USE_OLDJIS      0x0080
 124
 125 /* If set, do not produce ISO6429's direction specifying sequence.  */
 126 #define CODING_FLAG_ISO_NO_DIRECTION    0x0100
 127
 128 /* If set, assume designation states are reset at beginning of line on
 129    output.  */
 130 #define CODING_FLAG_ISO_INIT_AT_BOL     0x0200
 131
 132 /* If set, designation sequence should be placed at beginning of line
 133    on output.  */
 134 #define CODING_FLAG_ISO_DESIGNATE_AT_BOL 0x0400
 135
 136 /* If set, do not encode unsafe characters on output.  */
 137 #define CODING_FLAG_ISO_SAFE            0x0800
 138
 139 /* If set, extra latin codes (128..159) are accepted as a valid code
 140    on input.  */
 141 #define CODING_FLAG_ISO_LATIN_EXTRA     0x1000
 142
 143 /* If set, use designation escape sequence.  */
 144 #define CODING_FLAG_ISO_DESIGNATION     0x10000
 145
 146 /* A character to be produced on output if encoding of the original
 147    character is prohibited by CODING_FLAG_ISO_SAFE.  */
 148 #define CODING_INHIBIT_CHARACTER_SUBSTITUTION  077 /* 077 == `?' */
 149
 150 /* Structure of the field `spec.iso2022' in the structure `coding_system'.  */
 151 struct iso2022_spec
 152 {
 153   /* The current graphic register invoked to each graphic plane.  */
 154   int current_invocation[2];
 155
 156   /* The current charset designated to each graphic register.  */
 157   int current_designation[4];
 158
 159   /* A charset initially designated to each graphic register.  */
 160   int initial_designation[4];
 161
 162   /* If not -1, it is a graphic register specified in an invalid
 163      designation sequence.  */
 164   int last_invalid_designation_register;
 165
 166   /* A graphic register to which each charset should be designated.  */
 167   unsigned char requested_designation[MAX_CHARSET + 1];
 168
 169   /* A revision number to be specified for each charset on encoding.
 170      The value 255 means no revision number for the corresponding
 171      charset.  */
 172   unsigned char charset_revision_number[MAX_CHARSET + 1];
 173
 174   /* Set to 1 temporarily only when graphic register 2 or 3 is invoked
 175      by single-shift while encoding.  */
 176   int single_shifting;
 177
 178   /* Set to 1 temporarily only when processing at beginning of line.  */
 179   int bol;
 180 };
 181
 182 /* Macros to access each field in the structure `spec.iso2022'.  */
 183 #define CODING_SPEC_ISO_INVOCATION(coding, plane) \
 184   (coding)->spec.iso2022.current_invocation[plane]
 185 #define CODING_SPEC_ISO_DESIGNATION(coding, reg) \
 186   (coding)->spec.iso2022.current_designation[reg]
 187 #define CODING_SPEC_ISO_INITIAL_DESIGNATION(coding, reg) \
 188   (coding)->spec.iso2022.initial_designation[reg]
 189 #define CODING_SPEC_ISO_REQUESTED_DESIGNATION(coding, charset) \
 190   (coding)->spec.iso2022.requested_designation[charset]
 191 #define CODING_SPEC_ISO_REVISION_NUMBER(coding, charset) \
 192   (coding)->spec.iso2022.charset_revision_number[charset]
 193 #define CODING_SPEC_ISO_SINGLE_SHIFTING(coding) \
 194   (coding)->spec.iso2022.single_shifting
 195 #define CODING_SPEC_ISO_BOL(coding) \
 196   (coding)->spec.iso2022.bol
 197
 198 /* A value which may appear in
 199    coding->spec.iso2022.requested_designation indicating that the
 200    corresponding charset does not request any graphic register to be
 201    designated.  */
 202 #define CODING_SPEC_ISO_NO_REQUESTED_DESIGNATION 4
 203
 204 /* Return a charset which is currently designated to the graphic plane
 205    PLANE in the coding-system CODING.  */
 206 #define CODING_SPEC_ISO_PLANE_CHARSET(coding, plane)    \
 207   ((CODING_SPEC_ISO_INVOCATION (coding, plane) < 0)     \
 208    ? -1                                                 \
 209    : CODING_SPEC_ISO_DESIGNATION (coding,               \
 210                                   CODING_SPEC_ISO_INVOCATION (coding, plane)))
 211
 212 /*** BIG5 section ***/
 213
 214 /* Macros to denote each type of BIG5 coding system.  */
 215 #define CODING_FLAG_BIG5_HKU    0x00 /* BIG5-HKU is one of variants of
 216                                         BIG5 developed by Hong Kong
 217                                         University.  */
 218 #define CODING_FLAG_BIG5_ETEN   0x01 /* BIG5_ETen is one of variants
 219                                         of BIG5 developed by the
 220                                         company ETen in Taiwan.  */
 221
 222 /*** GENERAL section ***/
 223
 224 /* Types of coding system.  */
 225 enum coding_type
 226   {
 227     coding_type_no_conversion,  /* A coding system which requires no
 228                                    conversion for reading and writing
 229                                    including end-of-line format.  */
 230     coding_type_emacs_mule,     /* A coding system used in Emacs'
 231                                    buffer and string.  Requires no
 232                                    conversion for reading and writing
 233                                    except for end-of-line format.  */
 234     coding_type_undecided,      /* A coding system which requires
 235                                    automatic detection of a real
 236                                    coding system.  */
 237     coding_type_sjis,           /* SJIS coding system for Japanese.  */
 238     coding_type_iso2022,        /* Any coding system of ISO2022
 239                                    variants.  */
 240     coding_type_big5,           /* BIG5 coding system for Chinese.  */
 241     coding_type_ccl,            /* The coding system of which decoder
 242                                    and encoder are written in CCL.  */
 243     coding_type_raw_text        /* A coding system for a text
 244                                    containing random 8-bit code which
 245                                    does not require code conversion
 246                                    except for end-of-line format. */
 247   };
 248
 249 /* Formats of end-of-line.  */
 250 #define CODING_EOL_LF   0       /* Line-feed only, same as Emacs'
 251                                    internal format.  */
 252 #define CODING_EOL_CRLF 1       /* Sequence of carriage-return and
 253                                    line-feed.  */
 254 #define CODING_EOL_CR   2       /* Carriage-return only.  */
 255 #define CODING_EOL_UNDECIDED 3  /* This value is used to denote the
 256                                    eol-type is not yet decided.  */
 257 #define CODING_EOL_INCONSISTENT 4 /* This value is used to denote the
 258                                      eol-type is not consistent
 259                                      through the file.  */
 260
 261 /* 1 iff composing.  */
 262 #define COMPOSING_P(coding) ((int) coding->composing > (int) COMPOSITION_NO)
 263
 264 #define COMPOSITION_DATA_SIZE 4080
 265 #define COMPOSITION_DATA_MAX_BUNCH_LENGTH (4 + MAX_COMPOSITION_COMPONENTS*2)
 266
 267 /* Data structure to hold information about compositions of text that
 268    is being decoded or encode.  ISO 2022 base code conversion routines
 269    handle special ESC sequences for composition specification.  But,
 270    they can't get/put such information directly from/to a buffer in
 271    the deepest place.  So, they store or retrieve the information
 272    through this structure.
 273
 274    The encoder stores the information in this structure when it meets
 275    ESC sequences for composition while encoding codes, then, after all
 276    text codes are encoded, puts `composition' properties on the text
 277    by referring to the structure.
 278
 279    The decoder at first stores the information of a text to be
 280    decoded, then, while decoding codes, generates ESC sequences for
 281    composition at proper places by referring to the structure.  */
 282
 283 struct composition_data
 284 {
 285   /* The character position of the first character to be encoded or
 286      decoded.  START and END (see below) are relative to this
 287      position.  */
 288   int char_offset;
 289
 290   /* The composition data.  These elements are repeated for each
 291      composition:
 292         LENGTH START END METHOD [ COMPONENT ... ]
 293      where,
 294         LENGTH is the number of elements for this composition.
 295
 296         START and END are starting and ending character positions of
 297         the composition relative to `char_offset'.
 298
 299         METHOD is one of `enum composing_status' specifying the way of
 300         composition.
 301
 302         COMPONENT is a character or an encoded composition rule.  */
 303   int data[COMPOSITION_DATA_SIZE];
 304
 305   /* The number of elements in `data' currently used.  */
 306   int used;
 307
 308   /* Pointers to the previous and next structures.  When `data' is
 309      filled up, another structure is allocated and linked in `next'.
 310      The new structure has backward link to this structure in `prev'.
 311      The number of chained structures depends on how many compositions
 312      the text being encoded or decoded contains.  */
 313   struct composition_data *prev, *next;
 314 };
 315
 316 /* Macros used for the member `result' of the struct
 317    coding_system.  */
 318 #define CODING_FINISH_NORMAL            0
 319 #define CODING_FINISH_INSUFFICIENT_SRC  1
 320 #define CODING_FINISH_INSUFFICIENT_DST  2
 321 #define CODING_FINISH_INCONSISTENT_EOL  3
 322 #define CODING_FINISH_INSUFFICIENT_CMP  4
 323 #define CODING_FINISH_INTERRUPT         5
 324
 325 /* Macros used for the member `mode' of the struct coding_system.  */
 326
 327 /* If set, recover the original CR or LF of the already decoded text
 328    when the decoding routine encounters an inconsistent eol format.  */
 329 #define CODING_MODE_INHIBIT_INCONSISTENT_EOL    0x01
 330
 331 /* If set, the decoding/encoding routines treat the current data as
 332    the last block of the whole text to be converted, and do
 333    appropriate finishing job.  */
 334 #define CODING_MODE_LAST_BLOCK                  0x02
 335
 336 /* If set, it means that the current source text is in a buffer which
 337    enables selective display.  */
 338 #define CODING_MODE_SELECTIVE_DISPLAY           0x04
 339
 340 /* This flag is used by the decoding/encoding routines on the fly.  If
 341    set, it means that right-to-left text is being processed.  */
 342 #define CODING_MODE_DIRECTION                   0x08
 343
 344 struct coding_system
 345 {
 346   /* Type of the coding system.  */
 347   enum coding_type type;
 348
 349   /* Type of end-of-line format (LF, CRLF, or CR) of the coding system.  */
 350   int eol_type;
 351
 352   /* Flag bits of the coding system.  The meaning of each bit is common
 353      to all types of coding systems.  */
 354   unsigned int common_flags;
 355
 356   /* Flag bits of the coding system.  The meaning of each bit depends
 357      on the type of the coding system.  */
 358   unsigned int flags;
 359
 360   /* Mode bits of the coding system.  See the comments of the macros
 361      CODING_MODE_XXX.  */
 362   unsigned int mode;
 363
 364   /* The current status of composition handling.  */
 365   int composing;
 366
 367   /* 1 iff the next character is a composition rule.  */
 368   int composition_rule_follows;
 369
 370   /* Information of compositions are stored here on decoding and set
 371      in advance on encoding.  */
 372   struct composition_data *cmp_data;
 373
 374   /* Index to cmp_data->data for the first element for the current
 375      composition.  */
 376   int cmp_data_start;
 377
 378   /* Index to cmp_data->data for the current element for the current
 379      composition.  */
 380   int cmp_data_index;
 381
 382   /* Detailed information specific to each type of coding system.  */
 383   union spec
 384     {
 385       struct iso2022_spec iso2022;
 386       struct ccl_spec ccl;      /* Defined in ccl.h.  */
 387     } spec;
 388
 389   /* Index number of coding category of the coding system.  */
 390   int category_idx;
 391
 392   /* The following two members specify how characters 128..159 are
 393      represented in source and destination text respectively.  1 means
 394      they are represented by 2-byte sequence, 0 means they are
 395      represented by 1-byte as is (see the comment in charset.h).  */
 396   unsigned src_multibyte : 1;
 397   unsigned dst_multibyte : 1;
 398
 399   /* How may heading bytes we can skip for decoding.  This is set to
 400      -1 in setup_coding_system, and updated by detect_coding.  So,
 401      when this is equal to the byte length of the text being
 402      converted, we can skip the actual conversion process.  */
 403   int heading_ascii;
 404
 405   /* The following members are set by encoding/decoding routine.  */
 406   int produced, produced_char, consumed, consumed_char;
 407
 408   /* Number of error source data found in a decoding routine.  */
 409   int errors;
 410
 411   /* Finish status of code conversion.  It should be one of macros
 412      CODING_FINISH_XXXX.  */
 413   int result;
 414
 415   /* If nonzero, suppress error notification.  */
 416   int suppress_error;
 417
 418   /* The following members are all Lisp symbols.  We don't have to
 419      protect them from GC because the current garbage collection
 420      doesn't relocate Lisp symbols.  But, when it is changed, we must
 421      find a way to protect them.  */
 422
 423   /* Backward pointer to the Lisp symbol of the coding system.  */
 424   Lisp_Object symbol;
 425
 426   /* Lisp function (symbol) to be called after decoding to do
 427      additional conversion, or nil.  */
 428   Lisp_Object post_read_conversion;
 429
 430   /* Lisp function (symbol) to be called before encoding to do
 431      additional conversion, or nil.  */
 432   Lisp_Object pre_write_conversion;
 433
 434   /* Character translation tables to look up, or nil.  */
 435   Lisp_Object translation_table_for_decode;
 436   Lisp_Object translation_table_for_encode;
 437 };
 438
 439 #define CODING_REQUIRE_FLUSHING_MASK    1
 440 #define CODING_REQUIRE_DECODING_MASK    2
 441 #define CODING_REQUIRE_ENCODING_MASK    4
 442 #define CODING_REQUIRE_DETECTION_MASK   8
 443
 444 /* Return 1 if the coding system CODING requires specific code to be
 445    attached at the tail of converted text.  */
 446 #define CODING_REQUIRE_FLUSHING(coding) \
 447   ((coding)->common_flags & CODING_REQUIRE_FLUSHING_MASK)
 448
 449 /* Return 1 if the coding system CODING requires code conversion on
 450    decoding.  */
 451 #define CODING_REQUIRE_DECODING(coding) \
 452   ((coding)->dst_multibyte              \
 453    || (coding)->common_flags & CODING_REQUIRE_DECODING_MASK)
 454
 455 /* Return 1 if the coding system CODING requires code conversion on
 456    encoding.  */
 457 #define CODING_REQUIRE_ENCODING(coding) \
 458   ((coding)->src_multibyte              \
 459    || (coding)->common_flags & CODING_REQUIRE_ENCODING_MASK)
 460
 461 /* Return 1 if the coding system CODING requires some kind of code
 462    detection.  */
 463 #define CODING_REQUIRE_DETECTION(coding) \
 464   ((coding)->common_flags & CODING_REQUIRE_DETECTION_MASK)
 465
 466 /* Return 1 if the coding system CODING requires code conversion on
 467    decoding or some kind of code detection.  */
 468 #define CODING_MAY_REQUIRE_DECODING(coding)     \
 469   (CODING_REQUIRE_DECODING (coding)             \
 470    || CODING_REQUIRE_DETECTION (coding))
 471
 472 /* Index for each coding category in `coding_category_table' */
 473 #define CODING_CATEGORY_IDX_EMACS_MULE  0
 474 #define CODING_CATEGORY_IDX_SJIS        1
 475 #define CODING_CATEGORY_IDX_ISO_7       2
 476 #define CODING_CATEGORY_IDX_ISO_7_TIGHT 3
 477 #define CODING_CATEGORY_IDX_ISO_8_1     4
 478 #define CODING_CATEGORY_IDX_ISO_8_2     5
 479 #define CODING_CATEGORY_IDX_ISO_7_ELSE  6
 480 #define CODING_CATEGORY_IDX_ISO_8_ELSE  7
 481 #define CODING_CATEGORY_IDX_CCL         8
 482 #define CODING_CATEGORY_IDX_BIG5        9
 483 #define CODING_CATEGORY_IDX_UTF_8       10
 484 #define CODING_CATEGORY_IDX_UTF_16_BE   11
 485 #define CODING_CATEGORY_IDX_UTF_16_LE   12
 486 #define CODING_CATEGORY_IDX_RAW_TEXT    13
 487 #define CODING_CATEGORY_IDX_BINARY      14
 488 #define CODING_CATEGORY_IDX_MAX         15
 489
 490 /* Definitions of flag bits returned by the function
 491    detect_coding_mask ().  */
 492 #define CODING_CATEGORY_MASK_EMACS_MULE (1 << CODING_CATEGORY_IDX_EMACS_MULE)
 493 #define CODING_CATEGORY_MASK_SJIS       (1 << CODING_CATEGORY_IDX_SJIS)
 494 #define CODING_CATEGORY_MASK_ISO_7      (1 << CODING_CATEGORY_IDX_ISO_7)
 495 #define CODING_CATEGORY_MASK_ISO_7_TIGHT (1 << CODING_CATEGORY_IDX_ISO_7_TIGHT)
 496 #define CODING_CATEGORY_MASK_ISO_8_1    (1 << CODING_CATEGORY_IDX_ISO_8_1)
 497 #define CODING_CATEGORY_MASK_ISO_8_2    (1 << CODING_CATEGORY_IDX_ISO_8_2)
 498 #define CODING_CATEGORY_MASK_ISO_7_ELSE (1 << CODING_CATEGORY_IDX_ISO_7_ELSE)
 499 #define CODING_CATEGORY_MASK_ISO_8_ELSE (1 << CODING_CATEGORY_IDX_ISO_8_ELSE)
 500 #define CODING_CATEGORY_MASK_CCL        (1 << CODING_CATEGORY_IDX_CCL)
 501 #define CODING_CATEGORY_MASK_BIG5       (1 << CODING_CATEGORY_IDX_BIG5)
 502 #define CODING_CATEGORY_MASK_UTF_8      (1 << CODING_CATEGORY_IDX_UTF_8)
 503 #define CODING_CATEGORY_MASK_UTF_16_BE  (1 << CODING_CATEGORY_IDX_UTF_16_BE)
 504 #define CODING_CATEGORY_MASK_UTF_16_LE  (1 << CODING_CATEGORY_IDX_UTF_16_LE)
 505 #define CODING_CATEGORY_MASK_RAW_TEXT   (1 << CODING_CATEGORY_IDX_RAW_TEXT)
 506 #define CODING_CATEGORY_MASK_BINARY     (1 << CODING_CATEGORY_IDX_BINARY)
 507
 508 /* This value is returned if detect_coding_mask () find nothing other
 509    than ASCII characters.  */
 510 #define CODING_CATEGORY_MASK_ANY        \
 511   (  CODING_CATEGORY_MASK_EMACS_MULE    \
 512    | CODING_CATEGORY_MASK_SJIS          \
 513    | CODING_CATEGORY_MASK_ISO_7         \
 514    | CODING_CATEGORY_MASK_ISO_7_TIGHT   \
 515    | CODING_CATEGORY_MASK_ISO_8_1       \
 516    | CODING_CATEGORY_MASK_ISO_8_2       \
 517    | CODING_CATEGORY_MASK_ISO_7_ELSE    \
 518    | CODING_CATEGORY_MASK_ISO_8_ELSE    \
 519    | CODING_CATEGORY_MASK_CCL           \
 520    | CODING_CATEGORY_MASK_BIG5          \
 521    | CODING_CATEGORY_MASK_UTF_8         \
 522    | CODING_CATEGORY_MASK_UTF_16_BE     \
 523    | CODING_CATEGORY_MASK_UTF_16_LE)
 524
 525 #define CODING_CATEGORY_MASK_ISO_7BIT \
 526   (CODING_CATEGORY_MASK_ISO_7 | CODING_CATEGORY_MASK_ISO_7_TIGHT)
 527
 528 #define CODING_CATEGORY_MASK_ISO_8BIT \
 529   (CODING_CATEGORY_MASK_ISO_8_1 | CODING_CATEGORY_MASK_ISO_8_2)
 530
 531 #define CODING_CATEGORY_MASK_ISO_SHIFT \
 532   (CODING_CATEGORY_MASK_ISO_7_ELSE | CODING_CATEGORY_MASK_ISO_8_ELSE)
 533
 534 #define CODING_CATEGORY_MASK_ISO        \
 535   (  CODING_CATEGORY_MASK_ISO_7BIT      \
 536    | CODING_CATEGORY_MASK_ISO_SHIFT     \
 537    | CODING_CATEGORY_MASK_ISO_8BIT)
 538
 539 #define CODING_CATEGORY_MASK_UTF_16_BE_LE \
 540    (CODING_CATEGORY_MASK_UTF_16_BE | CODING_CATEGORY_MASK_UTF_16_LE)
 541
 542 /* Macros to decode or encode a character of JISX0208 in SJIS.  S1 and
 543    S2 are the 1st and 2nd position-codes of JISX0208 in SJIS coding
 544    system.  C1 and C2 are the 1st and 2nd position codes of Emacs'
 545    internal format.  */
 546
 547 #define DECODE_SJIS(s1, s2, c1, c2)                     \
 548   do {                                                  \
 549     if (s2 >= 0x9F)                                     \
 550       c1 = s1 * 2 - (s1 >= 0xE0 ? 0x160 : 0xE0),        \
 551       c2 = s2 - 0x7E;                                   \
 552     else                                                \
 553       c1 = s1 * 2 - ((s1 >= 0xE0) ? 0x161 : 0xE1),      \
 554       c2 = s2 - ((s2 >= 0x7F) ? 0x20 : 0x1F);           \
 555   } while (0)
 556
 557 #define ENCODE_SJIS(c1, c2, s1, s2)                     \
 558   do {                                                  \
 559     if (c1 & 1)                                         \
 560       s1 = c1 / 2 + ((c1 < 0x5F) ? 0x71 : 0xB1),        \
 561       s2 = c2 + ((c2 >= 0x60) ? 0x20 : 0x1F);           \
 562     else                                                \
 563       s1 = c1 / 2 + ((c1 < 0x5F) ? 0x70 : 0xB0),        \
 564       s2 = c2 + 0x7E;                                   \
 565   } while (0)
 566
 567 /* Encode the file name NAME using the specified coding system
 568    for file names, if any.  */
 569 #define ENCODE_FILE(name)                                                  \
 570   (! NILP (Vfile_name_coding_system)                                       \
 571    && XFASTINT (Vfile_name_coding_system) != 0                             \
 572    ? code_convert_string_norecord (name, Vfile_name_coding_system, 1)      \
 573    : (! NILP (Vdefault_file_name_coding_system)                            \
 574       && XFASTINT (Vdefault_file_name_coding_system) != 0                  \
 575       ? code_convert_string_norecord (name, Vdefault_file_name_coding_system, 1) \
 576       : name))
 577
 578 /* Decode the file name NAME using the specified coding system
 579    for file names, if any.  */
 580 #define DECODE_FILE(name)                                                  \
 581   (! NILP (Vfile_name_coding_system)                                       \
 582    && XFASTINT (Vfile_name_coding_system) != 0                             \
 583    ? code_convert_string_norecord (name, Vfile_name_coding_system, 0)      \
 584    : (! NILP (Vdefault_file_name_coding_system)                            \
 585       && XFASTINT (Vdefault_file_name_coding_system) != 0                  \
 586       ? code_convert_string_norecord (name, Vdefault_file_name_coding_system, 0) \
 587       : name))
 588
 589 #ifdef WINDOWSNT
 590 /* Encode the string STR using the specified coding system
 591    for w32 system functions, if any.  */
 592 #define ENCODE_SYSTEM(str)                                                 \
 593   (! NILP (Vw32_system_coding_system)                                      \
 594    && XFASTINT (Vw32_system_coding_system) != 0                            \
 595    ? code_convert_string_norecord (str, Vw32_system_coding_system, 1)      \
 596    : str)
 597
 598 /* Decode the string STR using the specified coding system
 599    for w32 system functions, if any.  */
 600 #define DECODE_SYSTEM(name)                                                \
 601   (! NILP (Vw32_system_coding_system)                                      \
 602    && XFASTINT (Vw32_system_coding_system) != 0                            \
 603    ? code_convert_string_norecord (str, Vw32_system_coding_system, 0)      \
 604    : str)
 605 #endif
 606
 607 /* Extern declarations.  */
 608 extern int decode_coding P_ ((struct coding_system *, unsigned char *,
 609                               unsigned char *, int, int));
 610 extern int encode_coding P_ ((struct coding_system *, unsigned char *,
 611                               unsigned char *, int, int));
 612 extern void coding_save_composition P_ ((struct coding_system *, int, int,
 613                                          Lisp_Object));
 614 extern void coding_free_composition_data P_ ((struct coding_system *));
 615 extern void coding_adjust_composition_offset P_ ((struct coding_system *,
 616                                                   int));
 617 extern void coding_allocate_composition_data P_ ((struct coding_system *,
 618                                                   int));
 619 extern void coding_restore_composition P_ ((struct coding_system *,
 620                                             Lisp_Object));
 621 extern int code_convert_region P_ ((int, int, int, int, struct coding_system *,
 622                                     int, int));
 623 extern int decoding_buffer_size P_ ((struct coding_system *, int));
 624 extern int encoding_buffer_size P_ ((struct coding_system *, int));
 625 extern void detect_coding P_ ((struct coding_system *, unsigned char *, int));
 626 extern void detect_eol P_ ((struct coding_system *, unsigned char *, int));
 627 extern int setup_coding_system P_ ((Lisp_Object, struct coding_system *));
 628 extern Lisp_Object code_convert_string P_ ((Lisp_Object,
 629                                             struct coding_system *, int, int));
 630 extern Lisp_Object code_convert_string1 P_ ((Lisp_Object, Lisp_Object,
 631                                              Lisp_Object, int));
 632 extern Lisp_Object code_convert_string_norecord P_ ((Lisp_Object, Lisp_Object,
 633                                                      int));
 634 extern void setup_raw_text_coding_system P_ ((struct coding_system *));
 635 extern Lisp_Object encode_coding_string P_ ((Lisp_Object,
 636                                              struct coding_system *, int));
 637 extern Lisp_Object decode_coding_string P_ ((Lisp_Object,
 638                                              struct coding_system *, int));
 639 extern Lisp_Object Qcoding_system, Qeol_type, Qcoding_category_index;
 640 extern Lisp_Object Qraw_text, Qemacs_mule;
 641 extern Lisp_Object Qbuffer_file_coding_system;
 642 extern Lisp_Object Vcoding_category_list;
 643
 644 extern Lisp_Object Qtranslation_table;
 645 extern Lisp_Object Qtranslation_table_id;
 646
 647 /* Mnemonic strings to indicate each type of end-of-line.  */
 648 extern Lisp_Object eol_mnemonic_unix, eol_mnemonic_dos, eol_mnemonic_mac;
 649 /* Mnemonic string to indicate type of end-of-line is not yet decided.  */
 650 extern Lisp_Object eol_mnemonic_undecided;
 651
 652 #ifdef emacs
 653 extern Lisp_Object Qfile_coding_system;
 654 extern Lisp_Object Qcall_process, Qcall_process_region, Qprocess_argument;
 655 extern Lisp_Object Qstart_process, Qopen_network_stream;
 656 extern Lisp_Object Qwrite_region;
 657
 658 extern char *emacs_strerror P_ ((int));
 659
 660 /* Coding-system for reading files and receiving data from process.  */
 661 extern Lisp_Object Vcoding_system_for_read;
 662 /* Coding-system for writing files and sending data to process.  */
 663 extern Lisp_Object Vcoding_system_for_write;
 664 /* Coding-system actually used in the latest I/O.  */
 665 extern Lisp_Object Vlast_coding_system_used;
 666 /* Coding-system to use with system messages (e.g. strerror).  */
 667 extern Lisp_Object Vlocale_coding_system;
 668
 669 /* If non-zero, process buffer inherits the coding system used to decode
 670    the subprocess output.  */
 671 extern int inherit_process_coding_system;
 672
 673 /* Coding-system to be used for encoding terminal output.  This
 674    structure contains information of a coding-system specified by the
 675    function `set-terminal-coding-system'.  */
 676 extern struct coding_system terminal_coding;
 677
 678 /* Coding system to be used to encode text for terminal display when
 679    terminal coding system is nil.  */
 680 extern struct coding_system safe_terminal_coding;
 681
 682 /* Coding-system of what is sent from terminal keyboard.  This
 683    structure contains information of a coding-system specified by the
 684    function `set-keyboard-coding-system'.  */
 685 extern struct coding_system keyboard_coding;
 686
 687 /* Default coding system to be used to write a file.  */
 688 extern struct coding_system default_buffer_file_coding;
 689
 690 /* Default coding systems used for process I/O.  */
 691 extern Lisp_Object Vdefault_process_coding_system;
 692
 693 /* Function to call to force a user to force select a proper coding
 694    system.  */
 695 extern Lisp_Object Vselect_safe_coding_system_function;
 696
 697 /* Coding system for file names, or nil if none.  */
 698 extern Lisp_Object Vfile_name_coding_system;
 699
 700 /* Coding system for file names used only when
 701    Vfile_name_coding_system is nil.  */
 702 extern Lisp_Object Vdefault_file_name_coding_system;
 703
 704 #ifdef WINDOWSNT
 705 /* Coding system for w32 system strings, or nil if none.  */
 706 extern Lisp_Object Vw32_system_coding_system;
 707 #endif
 708 #endif
 709
 710 /* Error signaled when there's a problem with detecting coding system */
 711 extern Lisp_Object Qcoding_system_error;
 712
 713 #endif /* EMACS_CODING_H */