src/coding.h

   1 /* Header for coding system handler.
   2    Copyright (C) 2001-2012  Free Software Foundation, Inc.
   3    Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   4      2005, 2006, 2007, 2008, 2009, 2010, 2011
   5      National Institute of Advanced Industrial Science and Technology (AIST)
   6      Registration Number H14PRO021
   7    Copyright (C) 2003
   8      National Institute of Advanced Industrial Science and Technology (AIST)
   9      Registration Number H13PRO009
  10
  11 This file is part of GNU Emacs.
  12
  13 GNU Emacs is free software: you can redistribute it and/or modify
  14 it under the terms of the GNU General Public License as published by
  15 the Free Software Foundation, either version 3 of the License, or
  16 (at your option) any later version.
  17
  18 GNU Emacs is distributed in the hope that it will be useful,
  19 but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 GNU General Public License for more details.
  22
  23 You should have received a copy of the GNU General Public License
  24 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  25
  26 #ifndef EMACS_CODING_H
  27 #define EMACS_CODING_H
  28
  29 /* Index to arguments of Fdefine_coding_system_internal.  */
  30
  31 enum define_coding_system_arg_index
  32   {
  33     coding_arg_name,
  34     coding_arg_mnemonic,
  35     coding_arg_coding_type,
  36     coding_arg_charset_list,
  37     coding_arg_ascii_compatible_p,
  38     coding_arg_decode_translation_table,
  39     coding_arg_encode_translation_table,
  40     coding_arg_post_read_conversion,
  41     coding_arg_pre_write_conversion,
  42     coding_arg_default_char,
  43     coding_arg_for_unibyte,
  44     coding_arg_plist,
  45     coding_arg_eol_type,
  46     coding_arg_max
  47   };
  48
  49 enum define_coding_iso2022_arg_index
  50   {
  51     coding_arg_iso2022_initial = coding_arg_max,
  52     coding_arg_iso2022_reg_usage,
  53     coding_arg_iso2022_request,
  54     coding_arg_iso2022_flags,
  55     coding_arg_iso2022_max
  56   };
  57
  58 enum define_coding_utf8_arg_index
  59   {
  60     coding_arg_utf8_bom = coding_arg_max,
  61     coding_arg_utf8_max
  62   };
  63
  64 enum define_coding_utf16_arg_index
  65   {
  66     coding_arg_utf16_bom = coding_arg_max,
  67     coding_arg_utf16_endian,
  68     coding_arg_utf16_max
  69   };
  70
  71 enum define_coding_ccl_arg_index
  72   {
  73     coding_arg_ccl_decoder = coding_arg_max,
  74     coding_arg_ccl_encoder,
  75     coding_arg_ccl_valids,
  76     coding_arg_ccl_max
  77   };
  78
  79 /* Hash table for all coding systems.  Keys are coding system symbols
  80    and values are spec vectors of the corresponding coding system.  A
  81    spec vector has the form [ ATTRS ALIASES EOL-TYPE ].  ATTRS is a
  82    vector of attribute of the coding system.  ALIASES is a list of
  83    aliases (symbols) of the coding system.  EOL-TYPE is `unix', `dos',
  84    `mac' or a vector of coding systems (symbols).  */
  85
  86 extern Lisp_Object Vcoding_system_hash_table;
  87
  88
  89 /* Enumeration of coding system type.  */
  90
  91 enum coding_system_type
  92   {
  93     coding_type_charset,
  94     coding_type_utf_8,
  95     coding_type_utf_16,
  96     coding_type_iso_2022,
  97     coding_type_emacs_mule,
  98     coding_type_sjis,
  99     coding_type_ccl,
 100     coding_type_raw_text,
 101     coding_type_undecided,
 102     coding_type_max
 103   };
 104
 105
 106 /* Enumeration of end-of-line format type.  */
 107
 108 enum end_of_line_type
 109   {
 110     eol_lf,             /* Line-feed only, same as Emacs' internal
 111                            format.  */
 112     eol_crlf,           /* Sequence of carriage-return and
 113                            line-feed.  */
 114     eol_cr,             /* Carriage-return only.  */
 115     eol_any,            /* Accept any of above.  Produce line-feed
 116                            only.  */
 117     eol_undecided,      /* This value is used to denote that the
 118                            eol-type is not yet undecided.  */
 119     eol_type_max
 120   };
 121
 122 /* Enumeration of index to an attribute vector of a coding system.  */
 123
 124 enum coding_attr_index
 125   {
 126     coding_attr_base_name,
 127     coding_attr_docstring,
 128     coding_attr_mnemonic,
 129     coding_attr_type,
 130     coding_attr_charset_list,
 131     coding_attr_ascii_compat,
 132     coding_attr_decode_tbl,
 133     coding_attr_encode_tbl,
 134     coding_attr_trans_tbl,
 135     coding_attr_post_read,
 136     coding_attr_pre_write,
 137     coding_attr_default_char,
 138     coding_attr_for_unibyte,
 139     coding_attr_plist,
 140
 141     coding_attr_category,
 142     coding_attr_safe_charsets,
 143
 144     /* The followings are extra attributes for each type.  */
 145     coding_attr_charset_valids,
 146
 147     coding_attr_ccl_decoder,
 148     coding_attr_ccl_encoder,
 149     coding_attr_ccl_valids,
 150
 151     coding_attr_iso_initial,
 152     coding_attr_iso_usage,
 153     coding_attr_iso_request,
 154     coding_attr_iso_flags,
 155
 156     coding_attr_utf_bom,
 157     coding_attr_utf_16_endian,
 158
 159     coding_attr_emacs_mule_full,
 160
 161     coding_attr_last_index
 162   };
 163
 164
 165 /* Macros to access an element of an attribute vector.  */
 166
 167 #define CODING_ATTR_BASE_NAME(attrs)    AREF (attrs, coding_attr_base_name)
 168 #define CODING_ATTR_TYPE(attrs)         AREF (attrs, coding_attr_type)
 169 #define CODING_ATTR_CHARSET_LIST(attrs) AREF (attrs, coding_attr_charset_list)
 170 #define CODING_ATTR_MNEMONIC(attrs)     AREF (attrs, coding_attr_mnemonic)
 171 #define CODING_ATTR_DOCSTRING(attrs)    AREF (attrs, coding_attr_docstring)
 172 #define CODING_ATTR_ASCII_COMPAT(attrs) AREF (attrs, coding_attr_ascii_compat)
 173 #define CODING_ATTR_DECODE_TBL(attrs)   AREF (attrs, coding_attr_decode_tbl)
 174 #define CODING_ATTR_ENCODE_TBL(attrs)   AREF (attrs, coding_attr_encode_tbl)
 175 #define CODING_ATTR_TRANS_TBL(attrs)    AREF (attrs, coding_attr_trans_tbl)
 176 #define CODING_ATTR_POST_READ(attrs)    AREF (attrs, coding_attr_post_read)
 177 #define CODING_ATTR_PRE_WRITE(attrs)    AREF (attrs, coding_attr_pre_write)
 178 #define CODING_ATTR_DEFAULT_CHAR(attrs) AREF (attrs, coding_attr_default_char)
 179 #define CODING_ATTR_FOR_UNIBYTE(attrs)  AREF (attrs, coding_attr_for_unibyte)
 180 #define CODING_ATTR_FLUSHING(attrs)     AREF (attrs, coding_attr_flushing)
 181 #define CODING_ATTR_PLIST(attrs)        AREF (attrs, coding_attr_plist)
 182 #define CODING_ATTR_CATEGORY(attrs)     AREF (attrs, coding_attr_category)
 183 #define CODING_ATTR_SAFE_CHARSETS(attrs)AREF (attrs, coding_attr_safe_charsets)
 184
 185
 186 /* Return the name of a coding system specified by ID.  */
 187 #define CODING_ID_NAME(id) \
 188   (HASH_KEY (XHASH_TABLE (Vcoding_system_hash_table), id))
 189
 190 /* Return the attribute vector of a coding system specified by ID.  */
 191
 192 #define CODING_ID_ATTRS(id)     \
 193   (AREF (HASH_VALUE (XHASH_TABLE (Vcoding_system_hash_table), id), 0))
 194
 195 /* Return the list of aliases of a coding system specified by ID.  */
 196
 197 #define CODING_ID_ALIASES(id)   \
 198   (AREF (HASH_VALUE (XHASH_TABLE (Vcoding_system_hash_table), id), 1))
 199
 200 /* Return the eol-type of a coding system specified by ID.  */
 201
 202 #define CODING_ID_EOL_TYPE(id)  \
 203   (AREF (HASH_VALUE (XHASH_TABLE (Vcoding_system_hash_table), id), 2))
 204
 205
 206 /* Return the spec vector of CODING_SYSTEM_SYMBOL.  */
 207
 208 #define CODING_SYSTEM_SPEC(coding_system_symbol)        \
 209   (Fgethash (coding_system_symbol, Vcoding_system_hash_table, Qnil))
 210
 211
 212 /* Return the ID of CODING_SYSTEM_SYMBOL.  */
 213
 214 #define CODING_SYSTEM_ID(coding_system_symbol)                  \
 215   hash_lookup (XHASH_TABLE (Vcoding_system_hash_table),         \
 216                coding_system_symbol, NULL)
 217
 218 /* Return 1 if CODING_SYSTEM_SYMBOL is a coding system.  */
 219
 220 #define CODING_SYSTEM_P(coding_system_symbol)           \
 221   (CODING_SYSTEM_ID (coding_system_symbol) >= 0         \
 222    || (! NILP (coding_system_symbol)                    \
 223        && ! NILP (Fcoding_system_p (coding_system_symbol))))
 224
 225 /* Check if X is a coding system or not.  */
 226
 227 #define CHECK_CODING_SYSTEM(x)                          \
 228   do {                                                  \
 229     if (CODING_SYSTEM_ID (x) < 0                        \
 230         && NILP (Fcheck_coding_system (x)))             \
 231       wrong_type_argument (Qcoding_system_p, (x));      \
 232   } while (0)
 233
 234
 235 /* Check if X is a coding system or not.  If it is, set SEPC to the
 236    spec vector of the coding system.  */
 237
 238 #define CHECK_CODING_SYSTEM_GET_SPEC(x, spec)           \
 239   do {                                                  \
 240     spec = CODING_SYSTEM_SPEC (x);                      \
 241     if (NILP (spec))                                    \
 242       {                                                 \
 243         Fcheck_coding_system (x);                       \
 244         spec = CODING_SYSTEM_SPEC (x);                  \
 245       }                                                 \
 246     if (NILP (spec))                                    \
 247       wrong_type_argument (Qcoding_system_p, (x));      \
 248   } while (0)
 249
 250
 251 /* Check if X is a coding system or not.  If it is, set ID to the
 252    ID of the coding system.  */
 253
 254 #define CHECK_CODING_SYSTEM_GET_ID(x, id)                       \
 255   do                                                            \
 256     {                                                           \
 257       id = CODING_SYSTEM_ID (x);                                \
 258       if (id < 0)                                               \
 259         {                                                       \
 260           Fcheck_coding_system (x);                             \
 261           id = CODING_SYSTEM_ID (x);                            \
 262         }                                                       \
 263       if (id < 0)                                               \
 264         wrong_type_argument (Qcoding_system_p, (x));    \
 265     } while (0)
 266
 267
 268 /*** GENERAL section ***/
 269
 270 /* Enumeration of result code of code conversion.  */
 271 enum coding_result_code
 272   {
 273     CODING_RESULT_SUCCESS,
 274     CODING_RESULT_INSUFFICIENT_SRC,
 275     CODING_RESULT_INSUFFICIENT_DST,
 276     CODING_RESULT_INCONSISTENT_EOL,
 277     CODING_RESULT_INVALID_SRC,
 278     CODING_RESULT_INTERRUPT,
 279     CODING_RESULT_INSUFFICIENT_MEM
 280   };
 281
 282
 283 /* Macros used for the member `mode' of the struct coding_system.  */
 284
 285 /* If set, recover the original CR or LF of the already decoded text
 286    when the decoding routine encounters an inconsistent eol format.  */
 287 #define CODING_MODE_INHIBIT_INCONSISTENT_EOL    0x01
 288
 289 /* If set, the decoding/encoding routines treat the current data as
 290    the last block of the whole text to be converted, and do the
 291    appropriate finishing job.  */
 292 #define CODING_MODE_LAST_BLOCK                  0x02
 293
 294 /* If set, it means that the current source text is in a buffer which
 295    enables selective display.  */
 296 #define CODING_MODE_SELECTIVE_DISPLAY           0x04
 297
 298 /* This flag is used by the decoding/encoding routines on the fly.  If
 299    set, it means that right-to-left text is being processed.  */
 300 #define CODING_MODE_DIRECTION                   0x08
 301
 302 #define CODING_MODE_FIXED_DESTINATION           0x10
 303
 304 /* If set, it means that the encoding routines produces some safe
 305    ASCII characters (usually '?') for unsupported characters.  */
 306 #define CODING_MODE_SAFE_ENCODING               0x20
 307
 308   /* For handling composition sequence.  */
 309 #include "composite.h"
 310
 311 enum composition_state
 312   {
 313     COMPOSING_NO,
 314     COMPOSING_CHAR,
 315     COMPOSING_RULE,
 316     COMPOSING_COMPONENT_CHAR,
 317     COMPOSING_COMPONENT_RULE
 318   };
 319
 320 /* Structure for the current composition status.  */
 321 struct composition_status
 322 {
 323   enum composition_state state;
 324   enum composition_method method;
 325   int old_form;           /* 0:pre-21 form, 1:post-21 form */
 326   int length;             /* number of elements produced in charbuf */
 327   int nchars;             /* number of characters composed */
 328   int ncomps;             /* number of composition components */
 329   /* Maximum carryover is for the case of COMPOSITION_WITH_RULE_ALTCHARS.
 330      See the comment in coding.c.  */
 331   int carryover[4               /* annotation header */
 332                 + MAX_COMPOSITION_COMPONENTS * 3 - 2 /* ALTs and RULEs */
 333                 + 2                                  /* intermediate -1 -1 */
 334                 + MAX_COMPOSITION_COMPONENTS         /* CHARs */
 335                 ];
 336 };
 337
 338
 339 /* Structure of the field `spec.iso_2022' in the structure
 340    `coding_system'.  */
 341 struct iso_2022_spec
 342 {
 343   /* Bit-wise-or of CODING_ISO_FLAG_XXX.  */
 344   unsigned flags;
 345
 346   /* The current graphic register invoked to each graphic plane.  */
 347   int current_invocation[2];
 348
 349   /* The current charset designated to each graphic register.  The
 350      value -1 means that not charset is designated, -2 means that
 351      there was an invalid designation previously.  */
 352   int current_designation[4];
 353
 354   /* Set to 1 temporarily only when graphic register 2 or 3 is invoked
 355      by single-shift while encoding.  */
 356   int single_shifting;
 357
 358   /* Set to 1 temporarily only when processing at beginning of line.  */
 359   int bol;
 360
 361   /* If positive, we are now scanning CTEXT extended segment.  */
 362   int ctext_extended_segment_len;
 363
 364   /* If nonzero, we are now scanning embedded UTF-8 sequence.  */
 365   int embedded_utf_8;
 366
 367   /* The current composition.  */
 368   struct composition_status cmp_status;
 369 };
 370
 371 struct emacs_mule_spec
 372 {
 373   int full_support;
 374   struct composition_status cmp_status;
 375 };
 376
 377 struct ccl_spec;
 378
 379 enum utf_bom_type
 380   {
 381     utf_detect_bom,
 382     utf_without_bom,
 383     utf_with_bom
 384   };
 385
 386 enum utf_16_endian_type
 387   {
 388     utf_16_big_endian,
 389     utf_16_little_endian
 390   };
 391
 392 struct utf_16_spec
 393 {
 394   enum utf_bom_type bom;
 395   enum utf_16_endian_type endian;
 396   int surrogate;
 397 };
 398
 399 struct coding_detection_info
 400 {
 401   /* Values of these members are bitwise-OR of CATEGORY_MASK_XXXs.  */
 402   /* Which categories are already checked.  */
 403   int checked;
 404   /* Which categories are strongly found.  */
 405   int found;
 406   /* Which categories are rejected.  */
 407   int rejected;
 408 };
 409
 410
 411 struct coding_system
 412 {
 413   /* ID number of the coding system.  This is an index to
 414      Vcoding_system_hash_table.  This value is set by
 415      setup_coding_system.  At the early stage of building time, this
 416      value is -1 in the array coding_categories to indicate that no
 417      coding-system of that category is yet defined.  */
 418   ptrdiff_t id;
 419
 420   /* Flag bits of the coding system.  The meaning of each bit is common
 421      to all types of coding systems.  */
 422   int common_flags;
 423
 424   /* Mode bits of the coding system.  See the comments of the macros
 425      CODING_MODE_XXX.  */
 426   unsigned int mode;
 427
 428   /* Detailed information specific to each type of coding system.  */
 429   union
 430     {
 431       struct iso_2022_spec iso_2022;
 432       struct ccl_spec *ccl;     /* Defined in ccl.h.  */
 433       struct utf_16_spec utf_16;
 434       enum utf_bom_type utf_8_bom;
 435       struct emacs_mule_spec emacs_mule;
 436     } spec;
 437
 438   int max_charset_id;
 439   unsigned char *safe_charsets;
 440
 441   /* The following two members specify how binary 8-bit code 128..255
 442      are represented in source and destination text respectively.  1
 443      means they are represented by 2-byte sequence, 0 means they are
 444      represented by 1-byte as is (see the comment in character.h).  */
 445   unsigned src_multibyte : 1;
 446   unsigned dst_multibyte : 1;
 447
 448   /* How may heading bytes we can skip for decoding.  This is set to
 449      -1 in setup_coding_system, and updated by detect_coding.  So,
 450      when this is equal to the byte length of the text being
 451      converted, we can skip the actual conversion process.  */
 452   EMACS_INT head_ascii;
 453
 454   /* The following members are set by encoding/decoding routine.  */
 455   EMACS_INT produced, produced_char, consumed, consumed_char;
 456
 457   /* Number of error source data found in a decoding routine.  */
 458   int errors;
 459
 460   /* Store the positions of error source data.  */
 461   EMACS_INT *error_positions;
 462
 463   /* Finish status of code conversion.  */
 464   enum coding_result_code result;
 465
 466   EMACS_INT src_pos, src_pos_byte, src_chars, src_bytes;
 467   Lisp_Object src_object;
 468   const unsigned char *source;
 469
 470   EMACS_INT dst_pos, dst_pos_byte, dst_bytes;
 471   Lisp_Object dst_object;
 472   unsigned char *destination;
 473
 474   /* Set to 1 if the source of conversion is not in the member
 475      `charbuf', but at `src_object'.  */
 476   int chars_at_source;
 477
 478   /* If an element is non-negative, it is a character code.
 479
 480      If it is in the range -128..-1, it is a 8-bit character code
 481      minus 256.
 482
 483      If it is less than -128, it specifies the start of an annotation
 484      chunk.  The length of the chunk is -128 minus the value of the
 485      element.  The following elements are OFFSET, ANNOTATION-TYPE, and
 486      a sequence of actual data for the annotation.  OFFSET is a
 487      character position offset from dst_pos or src_pos,
 488      ANNOTATION-TYPE specifies the meaning of the annotation and how to
 489      handle the following data..  */
 490   int *charbuf;
 491   int charbuf_size, charbuf_used;
 492
 493   /* Set to 1 if charbuf contains an annotation.  */
 494   int annotated;
 495
 496   unsigned char carryover[64];
 497   int carryover_bytes;
 498
 499   int default_char;
 500
 501   int (*detector) (struct coding_system *,
 502                    struct coding_detection_info *);
 503   void (*decoder) (struct coding_system *);
 504   int (*encoder) (struct coding_system *);
 505 };
 506
 507 /* Meanings of bits in the member `common_flags' of the structure
 508    coding_system.  The lowest 8 bits are reserved for various kind of
 509    annotations (currently two of them are used).  */
 510 #define CODING_ANNOTATION_MASK                  0x00FF
 511 #define CODING_ANNOTATE_COMPOSITION_MASK        0x0001
 512 #define CODING_ANNOTATE_DIRECTION_MASK          0x0002
 513 #define CODING_ANNOTATE_CHARSET_MASK            0x0003
 514 #define CODING_FOR_UNIBYTE_MASK                 0x0100
 515 #define CODING_REQUIRE_FLUSHING_MASK            0x0200
 516 #define CODING_REQUIRE_DECODING_MASK            0x0400
 517 #define CODING_REQUIRE_ENCODING_MASK            0x0800
 518 #define CODING_REQUIRE_DETECTION_MASK           0x1000
 519 #define CODING_RESET_AT_BOL_MASK                0x2000
 520
 521 /* Return 1 if the coding context CODING requires annotation
 522    handling.  */
 523 #define CODING_REQUIRE_ANNOTATION(coding) \
 524   ((coding)->common_flags & CODING_ANNOTATION_MASK)
 525
 526 /* Return 1 if the coding context CODING prefers decoding into unibyte.  */
 527 #define CODING_FOR_UNIBYTE(coding) \
 528   ((coding)->common_flags & CODING_FOR_UNIBYTE_MASK)
 529
 530 /* Return 1 if the coding context CODING requires specific code to be
 531    attached at the tail of converted text.  */
 532 #define CODING_REQUIRE_FLUSHING(coding) \
 533   ((coding)->common_flags & CODING_REQUIRE_FLUSHING_MASK)
 534
 535 /* Return 1 if the coding context CODING requires code conversion on
 536    decoding.  */
 537 #define CODING_REQUIRE_DECODING(coding) \
 538   ((coding)->dst_multibyte              \
 539    || (coding)->common_flags & CODING_REQUIRE_DECODING_MASK)
 540
 541
 542 /* Return 1 if the coding context CODING requires code conversion on
 543    encoding.
 544    The non-multibyte part of the condition is to support encoding of
 545    unibyte strings/buffers generated by string-as-unibyte or
 546    (set-buffer-multibyte nil) from multibyte strings/buffers.  */
 547 #define CODING_REQUIRE_ENCODING(coding)                         \
 548   ((coding)->src_multibyte                                      \
 549    || (coding)->common_flags & CODING_REQUIRE_ENCODING_MASK     \
 550    || (coding)->mode & CODING_MODE_SELECTIVE_DISPLAY)
 551
 552
 553 /* Return 1 if the coding context CODING requires some kind of code
 554    detection.  */
 555 #define CODING_REQUIRE_DETECTION(coding) \
 556   ((coding)->common_flags & CODING_REQUIRE_DETECTION_MASK)
 557
 558 /* Return 1 if the coding context CODING requires code conversion on
 559    decoding or some kind of code detection.  */
 560 #define CODING_MAY_REQUIRE_DECODING(coding)     \
 561   (CODING_REQUIRE_DECODING (coding)             \
 562    || CODING_REQUIRE_DETECTION (coding))
 563
 564 /* Macros to decode or encode a character of JISX0208 in SJIS.  S1 and
 565    S2 are the 1st and 2nd position-codes of JISX0208 in SJIS coding
 566    system.  C1 and C2 are the 1st and 2nd position codes of Emacs'
 567    internal format.  */
 568
 569 #define SJIS_TO_JIS(code)                               \
 570   do {                                                  \
 571     int s1, s2, j1, j2;                                 \
 572                                                         \
 573     s1 = (code) >> 8, s2 = (code) & 0xFF;               \
 574                                                         \
 575     if (s2 >= 0x9F)                                     \
 576       (j1 = s1 * 2 - (s1 >= 0xE0 ? 0x160 : 0xE0),       \
 577        j2 = s2 - 0x7E);                                 \
 578     else                                                \
 579       (j1 = s1 * 2 - ((s1 >= 0xE0) ? 0x161 : 0xE1),     \
 580        j2 = s2 - ((s2 >= 0x7F) ? 0x20 : 0x1F));         \
 581     (code) = (j1 << 8) | j2;                            \
 582   } while (0)
 583
 584 #define SJIS_TO_JIS2(code)                              \
 585   do {                                                  \
 586     int s1, s2, j1, j2;                                 \
 587                                                         \
 588     s1 = (code) >> 8, s2 = (code) & 0xFF;               \
 589                                                         \
 590     if (s2 >= 0x9F)                                     \
 591       {                                                 \
 592         j1 = (s1 == 0xF0 ? 0x28                         \
 593               : s1 == 0xF1 ? 0x24                       \
 594               : s1 == 0xF2 ? 0x2C                       \
 595               : s1 == 0xF3 ? 0x2E                       \
 596               : 0x6E + (s1 - 0xF4) * 2);                \
 597         j2 = s2 - 0x7E;                                 \
 598       }                                                 \
 599     else                                                \
 600       {                                                 \
 601         j1 = (s1 <= 0xF2 ? 0x21 + (s1 - 0xF0) * 2       \
 602               : s1 <= 0xF4 ? 0x2D + (s1 - 0xF3) * 2     \
 603               : 0x6F + (s1 - 0xF5) * 2);                \
 604         j2 = s2 - ((s2 >= 0x7F ? 0x20 : 0x1F));         \
 605       }                                                 \
 606     (code) = (j1 << 8) | j2;                            \
 607   } while (0)
 608
 609
 610 #define JIS_TO_SJIS(code)                               \
 611   do {                                                  \
 612     int s1, s2, j1, j2;                                 \
 613                                                         \
 614     j1 = (code) >> 8, j2 = (code) & 0xFF;               \
 615     if (j1 & 1)                                         \
 616       (s1 = j1 / 2 + ((j1 < 0x5F) ? 0x71 : 0xB1),       \
 617        s2 = j2 + ((j2 >= 0x60) ? 0x20 : 0x1F));         \
 618     else                                                \
 619       (s1 = j1 / 2 + ((j1 < 0x5F) ? 0x70 : 0xB0),       \
 620        s2 = j2 + 0x7E);                                 \
 621     (code) = (s1 << 8) | s2;                            \
 622   } while (0)
 623
 624 #define JIS_TO_SJIS2(code)                              \
 625   do {                                                  \
 626     int s1, s2, j1, j2;                                 \
 627                                                         \
 628     j1 = (code) >> 8, j2 = (code) & 0xFF;               \
 629     if (j1 & 1)                                         \
 630       {                                                 \
 631         s1 = (j1 <= 0x25 ? 0xF0 + (j1 - 0x21) / 2       \
 632               : j1 <= 0x2F ? 0xF3 + (j1 - 0x2D) / 2     \
 633               : 0xF5 + (j1 - 0x6F) / 2);                \
 634         s2 = j2 + ((j2 >= 0x60) ? 0x20 : 0x1F);         \
 635       }                                                 \
 636     else                                                \
 637       {                                                 \
 638         s1 = (j1 == 0x28 ? 0xF0                         \
 639               : j1 == 0x24 ? 0xF1                       \
 640               : j1 == 0x2C ? 0xF2                       \
 641               : j1 == 0x2E ? 0xF3                       \
 642               : 0xF4 + (j1 - 0x6E) / 2);                \
 643         s2 = j2 + 0x7E;                                 \
 644       }                                                 \
 645     (code) = (s1 << 8) | s2;                            \
 646   } while (0)
 647
 648 /* Encode the file name NAME using the specified coding system
 649    for file names, if any.  */
 650 #define ENCODE_FILE(name)                                                  \
 651   (! NILP (Vfile_name_coding_system)                                       \
 652    && !EQ (Vfile_name_coding_system, make_number (0))                      \
 653    ? code_convert_string_norecord (name, Vfile_name_coding_system, 1)      \
 654    : (! NILP (Vdefault_file_name_coding_system)                            \
 655       && !EQ (Vdefault_file_name_coding_system, make_number (0))           \
 656       ? code_convert_string_norecord (name, Vdefault_file_name_coding_system, 1) \
 657       : name))
 658
 659
 660 /* Decode the file name NAME using the specified coding system
 661    for file names, if any.  */
 662 #define DECODE_FILE(name)                                                  \
 663   (! NILP (Vfile_name_coding_system)                                       \
 664    && !EQ (Vfile_name_coding_system, make_number (0))                      \
 665    ? code_convert_string_norecord (name, Vfile_name_coding_system, 0)      \
 666    : (! NILP (Vdefault_file_name_coding_system)                            \
 667       && !EQ (Vdefault_file_name_coding_system, make_number (0))           \
 668       ? code_convert_string_norecord (name, Vdefault_file_name_coding_system, 0) \
 669       : name))
 670
 671
 672 /* Encode the string STR using the specified coding system
 673    for system functions, if any.  */
 674 #define ENCODE_SYSTEM(str)                                                 \
 675   (! NILP (Vlocale_coding_system)                                          \
 676    && !EQ (Vlocale_coding_system, make_number (0))                         \
 677    ? code_convert_string_norecord (str, Vlocale_coding_system, 1)          \
 678    : str)
 679
 680 /* Decode the string STR using the specified coding system
 681    for system functions, if any.  */
 682 #define DECODE_SYSTEM(str)                                                 \
 683   (! NILP (Vlocale_coding_system)                                          \
 684    && !EQ (Vlocale_coding_system, make_number (0))                         \
 685    ? code_convert_string_norecord (str, Vlocale_coding_system, 0)          \
 686    : str)
 687
 688 /* Note that this encodes utf-8, not utf-8-emacs, so it's not a no-op.  */
 689 #define ENCODE_UTF_8(str) code_convert_string_norecord (str, Qutf_8, 1)
 690
 691 /* Extern declarations.  */
 692 extern Lisp_Object code_conversion_save (int, int);
 693 extern int decoding_buffer_size (struct coding_system *, int);
 694 extern int encoding_buffer_size (struct coding_system *, int);
 695 extern void setup_coding_system (Lisp_Object, struct coding_system *);
 696 extern Lisp_Object coding_charset_list (struct coding_system *);
 697 extern Lisp_Object coding_system_charset_list (Lisp_Object);
 698 extern Lisp_Object code_convert_string (Lisp_Object, Lisp_Object,
 699                                         Lisp_Object, int, int, int);
 700 extern Lisp_Object code_convert_string_norecord (Lisp_Object, Lisp_Object,
 701                                                  int);
 702 extern Lisp_Object raw_text_coding_system (Lisp_Object);
 703 extern Lisp_Object coding_inherit_eol_type (Lisp_Object, Lisp_Object);
 704 extern Lisp_Object complement_process_encoding_system (Lisp_Object);
 705
 706 extern int decode_coding_gap (struct coding_system *,
 707                               EMACS_INT, EMACS_INT);
 708 extern void decode_coding_object (struct coding_system *,
 709                                   Lisp_Object, EMACS_INT, EMACS_INT,
 710                                   EMACS_INT, EMACS_INT, Lisp_Object);
 711 extern void encode_coding_object (struct coding_system *,
 712                                   Lisp_Object, EMACS_INT, EMACS_INT,
 713                                   EMACS_INT, EMACS_INT, Lisp_Object);
 714
 715 /* Macros for backward compatibility.  */
 716
 717 #define decode_coding_region(coding, from, to)          \
 718   decode_coding_object (coding, Fcurrent_buffer (),     \
 719                         from, CHAR_TO_BYTE (from),      \
 720                         to, CHAR_TO_BYTE (to), Fcurrent_buffer ())
 721
 722
 723 #define encode_coding_region(coding, from, to)          \
 724   encode_coding_object (coding, Fcurrent_buffer (),     \
 725                         from, CHAR_TO_BYTE (from),      \
 726                         to, CHAR_TO_BYTE (to), Fcurrent_buffer ())
 727
 728
 729 #define decode_coding_string(coding, string, nocopy)                    \
 730   decode_coding_object (coding, string, 0, 0, SCHARS (string),          \
 731                         SBYTES (string), Qt)
 732
 733 #define encode_coding_string(coding, string, nocopy)                    \
 734   (STRING_MULTIBYTE(string) ?                                           \
 735     (encode_coding_object (coding, string, 0, 0, SCHARS (string),       \
 736                            SBYTES (string), Qt),                        \
 737      (coding)->dst_object) : (string))
 738
 739
 740 #define decode_coding_c_string(coding, src, bytes, dst_object)          \
 741   do {                                                                  \
 742     (coding)->source = (src);                                           \
 743     (coding)->src_chars = (coding)->src_bytes = (bytes);                \
 744     decode_coding_object ((coding), Qnil, 0, 0, (bytes), (bytes),       \
 745                           (dst_object));                                \
 746   } while (0)
 747
 748
 749 extern Lisp_Object preferred_coding_system (void);
 750
 751
 752 extern Lisp_Object Qutf_8, Qutf_8_emacs;
 753
 754 extern Lisp_Object Qcoding_category_index;
 755 extern Lisp_Object Qcoding_system_p;
 756 extern Lisp_Object Qraw_text, Qemacs_mule, Qno_conversion, Qundecided;
 757 extern Lisp_Object Qbuffer_file_coding_system;
 758
 759 extern Lisp_Object Qunix, Qdos, Qmac;
 760
 761 extern Lisp_Object Qtranslation_table;
 762 extern Lisp_Object Qtranslation_table_id;
 763
 764 #ifdef emacs
 765 extern Lisp_Object Qfile_coding_system;
 766 extern Lisp_Object Qcall_process, Qcall_process_region;
 767 extern Lisp_Object Qstart_process, Qopen_network_stream;
 768 extern Lisp_Object Qwrite_region;
 769
 770 extern char *emacs_strerror (int);
 771
 772 /* Coding system to be used to encode text for terminal display when
 773    terminal coding system is nil.  */
 774 extern struct coding_system safe_terminal_coding;
 775
 776 #endif
 777
 778 /* Error signaled when there's a problem with detecting coding system */
 779 extern Lisp_Object Qcoding_system_error;
 780
 781 extern char emacs_mule_bytes[256];
 782 extern int emacs_mule_string_char (unsigned char *);
 783
 784 #endif /* EMACS_CODING_H */