[bpt/emacs.git] / src / coding.h

/* Header for coding system handler.
   Copyright (C) 1995, 1997 Electrotechnical Laboratory, JAPAN.
   Licensed to the Free Software Foundation.

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#ifndef _CODING_H
#define _CODING_H

#ifndef _CCL_H
#include "../src/ccl.h"
#endif

/*** EMACS' INTERNAL FORMAT (emacs-mule) section ***/

/* All code (1-byte) of Emacs' internal format is classified into one
   of the followings.  See also `charset.h'.  */
enum emacs_code_class_type
  {
    EMACS_control_code,		/* Control codes in the range
				   0x00..0x1F and 0x7F except for the
				   following two codes.  */
    EMACS_linefeed_code,	/* 0x0A (linefeed) to denote
				   end-of-line.  */
    EMACS_carriage_return_code,	/* 0x0D (carriage-return) to be used
				   in selective display mode.  */
    EMACS_ascii_code,		/* ASCII characters.  */
    EMACS_leading_code_composition, /* Leading code of a composite
				       character.  */
    EMACS_leading_code_2,	/* Base leading code of official
				   TYPE9N character.  */
    EMACS_leading_code_3,	/* Base leading code of private TYPE9N
				   or official TYPE9Nx9N character.  */
    EMACS_leading_code_4,	/* Base leading code of private
				   TYPE9Nx9N character.  */
    EMACS_invalid_code		/* Invalid code, i.e. a base leading
				   code not yet assigned to any
				   charset, or a code of the range
				   0xA0..0xFF.  */
  };

extern enum emacs_code_class_type emacs_code_class[256];

/*** ISO2022 section ***/

/* Macros to define code of control characters for ISO2022's functions.  */
			/* code */	/* function */
#define ISO_CODE_LF	0x0A		/* line-feed */
#define ISO_CODE_CR	0x0D		/* carriage-return */
#define ISO_CODE_SO	0x0E		/* shift-out */
#define ISO_CODE_SI	0x0F		/* shift-in */
#define ISO_CODE_SS2_7	0x19		/* single-shift-2 for 7-bit code */
#define ISO_CODE_ESC	0x1B		/* escape */
#define ISO_CODE_SS2	0x8E		/* single-shift-2 */
#define ISO_CODE_SS3	0x8F		/* single-shift-3 */
#define ISO_CODE_CSI	0x9B		/* control-sequence-introduce */

/* All code (1-byte) of ISO2022 is classified into one of the
   followings.  */
enum iso_code_class_type
  {
    ISO_control_code,		/* Control codes in the range
				   0x00..0x1F, 0x7F, and 0x80..0x9F,
				   except for the following seven
				   codes.  */
    ISO_carriage_return,	/* ISO_CODE_CR (0x0D) */
    ISO_shift_out,		/* ISO_CODE_SO (0x0E) */
    ISO_shift_in,		/* ISO_CODE_SI (0x0F) */
    ISO_single_shift_2_7,	/* ISO_CODE_SS2_7 (0x19) */
    ISO_escape,			/* ISO_CODE_SO (0x1B) */
    ISO_single_shift_2,		/* ISO_CODE_SS2 (0x8E) */
    ISO_single_shift_3,		/* ISO_CODE_SS3 (0x8F) */
    ISO_control_sequence_introducer, /* ISO_CODE_CSI (0x9B) */
    ISO_0x20_or_0x7F,		/* Codes of the values 0x20 or 0x7F.  */
    ISO_graphic_plane_0,	/* Graphic codes in the range 0x21..0x7E.  */
    ISO_0xA0_or_0xFF,		/* Codes of the values 0xA0 or 0xFF.  */
    ISO_graphic_plane_1		/* Graphic codes in the range 0xA1..0xFE.  */
  };

/** The macros CODING_FLAG_ISO_XXX defines a flag bit of the `flags'
  element in the structure `coding_system'.  This information is used
  while encoding a text to ISO2022.  **/

/* If set, produce short-form designation sequence (e.g. ESC $ A)
   instead of long-form sequence (e.g. ESC $ ( A).  */
#define CODING_FLAG_ISO_SHORT_FORM	0x0001

/* If set, reset graphic planes and registers at end-of-line to the
   initial state.  */
#define CODING_FLAG_ISO_RESET_AT_EOL	0x0002

/* If set, reset graphic planes and registers before any control
   characters to the initial state.  */
#define CODING_FLAG_ISO_RESET_AT_CNTL	0x0004

/* If set, encode by 7-bit environment.  */
#define CODING_FLAG_ISO_SEVEN_BITS	0x0008

/* If set, use locking-shift function.  */
#define CODING_FLAG_ISO_LOCKING_SHIFT	0x0010

/* If set, use single-shift function.  Overwrite
   CODING_FLAG_ISO_LOCKING_SHIFT.  */
#define CODING_FLAG_ISO_SINGLE_SHIFT	0x0020

/* If set, designate JISX0201-Roman instead of ASCII.  */
#define CODING_FLAG_ISO_USE_ROMAN	0x0040

/* If set, designate JISX0208-1978 instead of JISX0208-1983.  */
#define CODING_FLAG_ISO_USE_OLDJIS	0x0080

/* If set, do not produce ISO6429's direction specifying sequence.  */
#define CODING_FLAG_ISO_NO_DIRECTION	0x0100

/* If set, assume designation states are reset at beginning of line on
   output.  */
#define CODING_FLAG_ISO_INIT_AT_BOL	0x0200

/* If set, designation sequence should be placed at beginning of line
   on output.  */
#define CODING_FLAG_ISO_DESIGNATE_AT_BOL 0x0400

/* If set, do not encode unexpected charactes on output.  */
#define CODING_FLAG_ISO_SAFE		0x0800

/* A character to be produced on output if encoding of the original
   character is prohibited by CODING_FLAG_ISO_SAFE.  */
#define CODING_INHIBIT_CHARACTER_SUBSTITUTION  077 /* `?' */

/* Structure of the field `spec.iso2022' in the structure `coding_system'.  */
struct iso2022_spec
{
  /* The current graphic register invoked to each graphic plane.  */
  int current_invocation[2];

  /* The current charset designated to each graphic register.  */
  int current_designation[4];

  /* A charset initially designated to each graphic register.  */
  int initial_designation[4];

  /* A graphic register to which each charset should be designated.  */
  unsigned char requested_designation[MAX_CHARSET + 1];

  /* Set to 1 temporarily only when graphic register 2 or 3 is invoked
     by single-shift while encoding.  */
  int single_shifting;

  /* Set to 1 temporarily only when processing at beginning of line.  */
  int bol;
};

/* Macros to access each field in the structure `spec.iso2022'.  */
#define CODING_SPEC_ISO_INVOCATION(coding, plane) \
  coding->spec.iso2022.current_invocation[plane]
#define CODING_SPEC_ISO_DESIGNATION(coding, reg) \
  coding->spec.iso2022.current_designation[reg]
#define CODING_SPEC_ISO_INITIAL_DESIGNATION(coding, reg) \
  coding->spec.iso2022.initial_designation[reg]
#define CODING_SPEC_ISO_REQUESTED_DESIGNATION(coding, charset) \
  coding->spec.iso2022.requested_designation[charset]
#define CODING_SPEC_ISO_SINGLE_SHIFTING(coding) \
  coding->spec.iso2022.single_shifting
#define CODING_SPEC_ISO_BOL(coding) \
  coding->spec.iso2022.bol

/* A value which may appear in
   coding->spec.iso2022.requested_designation indicating that the
   corresponding charset does not request any graphic register to be
   designated.  */
#define CODING_SPEC_ISO_NO_REQUESTED_DESIGNATION 4

/* Return a charset which is currently designated to the graphic plane
   PLANE in the coding-system CODING.  */
#define CODING_SPEC_ISO_PLANE_CHARSET(coding, plane)	\
  ((CODING_SPEC_ISO_INVOCATION (coding, plane) < 0)	\
   ? -1							\
   : CODING_SPEC_ISO_DESIGNATION (coding,		\
				  CODING_SPEC_ISO_INVOCATION (coding, plane)))

/*** BIG5 section ***/

/* Macros to denote each type of BIG5 coding system.  */
#define CODING_FLAG_BIG5_HKU	0x00 /* BIG5-HKU is one of variants of
					BIG5 developed by Hong Kong
					University.  */
#define CODING_FLAG_BIG5_ETEN	0x01 /* BIG5_ETen is one of variants
					of BIG5 developed by the
					company ETen in Taiwan.  */

/*** GENERAL section ***/

/* Types of coding system.  */
enum coding_type
  {
    coding_type_no_conversion,	/* A coding system which requires no
				   conversion for reading and writing
				   including end-of-line format.  */
    coding_type_emacs_mule,	/* A coding system used in Emacs'
				   buffer and string.  Requires no
				   conversion for reading and writing
				   except for end-of-line format.  */
    coding_type_undecided,	/* A coding system which requires
				   automatic detection of a real
				   coding system.  */
    coding_type_sjis,		/* SJIS coding system for Japanese.  */
    coding_type_iso2022,	/* Any coding system of ISO2022
				   variants.  */
    coding_type_big5,		/* BIG5 coding system for Chinese.  */
    coding_type_ccl		/* The coding system of which decoder
				   and encoder are written in CCL.  */
  };

/* Formats of end-of-line.  */
#define CODING_EOL_LF	0	/* Line-feed only, same as Emacs'
				   internal format.  */
#define CODING_EOL_CRLF	1	/* Sequence of carriage-return and
				   line-feed.  */
#define CODING_EOL_CR	2	/* Carriage-return only.  */
#define CODING_EOL_UNDECIDED 3	/* This value is used to denote the
				   eol-type is not yet decided.  */

/* Character composition status while encoding/decoding.  */
#define COMPOSING_NO		 0 /* not composing */
#define COMPOSING_WITH_RULE_HEAD 1 /* 1st char of with-rule composing follow */
#define COMPOSING_NO_RULE_HEAD	 2 /* 1st char of no-rule composing follow */
#define COMPOSING_WITH_RULE_TAIL 3 /* Nth char of with-rule composing follow */
#define COMPOSING_NO_RULE_TAIL	 4 /* Nth char of no-rule composing follow */
#define COMPOSING_WITH_RULE_RULE 5 /* composition rule follow */

/* 1 iff composing.  */
#define COMPOSING_P(composing) (composing)
/* 1 iff 1st char of composing element follows.  */
#define COMPOSING_HEAD_P(composing) \
  ((composing) && (composing) <= COMPOSING_NO_RULE_HEAD)
/* 1 iff composing with embeded composition rule.  */
#define COMPOSING_WITH_RULE_P(composing) ((composing) & 1)

struct coding_system
{
  /* Type of the coding system.  */
  enum coding_type type;

  /* If the coding system requires specific code to be attached at the
     tail of converted text, this value should be set to `1'.  */
  int require_flushing;

  /* Flag bits of the coding system.  The meaning of each bit depends
     on the type of the coding system.  */
  unsigned int flags;

  /* Type of end-of-line format (LF, CRLF, or CR) of the coding system.  */
  int eol_type;

  /* Non-zero means that the current source text is the last block of the
     whole text to be converted.  */
  int last_block;

  /* Non-zero means that characters are being composed currently while
     decoding or encoding.  See macros COMPOSING_XXXX above for the
     meaing of each non-zero value.  */
  int composing;

  /* 0 (left-to-right) or 1 (right-to-left): the direction of the text
     being processed currently.  */
  int direction;

  /* Non-zero means that the current source text is in a buffer which
     enables selective display.  */
  int selective;

  /* Detailed information specific to each type of coding system.  */
  union spec
    {
      struct iso2022_spec iso2022;
      struct ccl_spec ccl;	/* Defined in ccl.h.  */
    } spec;

  /* Backward pointer to the Lisp symbol of the coding system.  */
  Lisp_Object symbol;

  /* Lisp function (symbol) to be called after decoding to do
     additional conversion. */
  Lisp_Object post_read_conversion;

  /* Lisp function (symbol) to be called before encoding to do
     additional conversion. */
  Lisp_Object pre_write_conversion;

  /* Character unification tables to look up, or nil.  */
  Lisp_Object character_unification_table_for_decode;
  Lisp_Object character_unification_table_for_encode;

  /* Carryover yielded by decoding/encoding incomplete source.  No
     coding-system yields more than 7-byte of carryover.  This does
     not include a text which is not processed because of short of
     output buffer.  */
  char carryover[8];

  /* Actual data length in the above array.  */
  int carryover_size;
};

/* Return 1 if coding system CODING never requires any code conversion.  */
#define CODING_REQUIRE_NO_CONVERSION(coding)		\
  (((coding)->type == coding_type_no_conversion		\
    || (coding)->type == coding_type_emacs_mule)	\
   && (coding)->eol_type == CODING_EOL_LF)

/* Return 1 if coding system CODING may not require code conversion.  */
#define CODING_MAY_REQUIRE_NO_CONVERSION(coding)	\
  (((coding)->type == coding_type_no_conversion		\
    || (coding)->type == coding_type_emacs_mule		\
    || (coding)->type == coding_type_undecided)		\
   && ((coding)->eol_type == CODING_EOL_LF		\
       || (coding)->eol_type == CODING_EOL_UNDECIDED))

/* Index for each coding category in `coding_category_table' */
#define CODING_CATEGORY_IDX_EMACS_MULE	0
#define CODING_CATEGORY_IDX_SJIS	1
#define CODING_CATEGORY_IDX_ISO_7	2
#define CODING_CATEGORY_IDX_ISO_8_1	3
#define CODING_CATEGORY_IDX_ISO_8_2	4
#define CODING_CATEGORY_IDX_ISO_7_ELSE	5
#define CODING_CATEGORY_IDX_ISO_8_ELSE	6
#define CODING_CATEGORY_IDX_BIG5	7
#define CODING_CATEGORY_IDX_BINARY	8
#define CODING_CATEGORY_IDX_MAX		9

/* Definitions of flag bits returned by the function
   detect_coding_mask ().  */
#define CODING_CATEGORY_MASK_EMACS_MULE	(1 << CODING_CATEGORY_IDX_EMACS_MULE)
#define CODING_CATEGORY_MASK_SJIS	(1 << CODING_CATEGORY_IDX_SJIS)
#define CODING_CATEGORY_MASK_ISO_7	(1 << CODING_CATEGORY_IDX_ISO_7)
#define CODING_CATEGORY_MASK_ISO_8_1	(1 << CODING_CATEGORY_IDX_ISO_8_1)
#define CODING_CATEGORY_MASK_ISO_8_2	(1 << CODING_CATEGORY_IDX_ISO_8_2)
#define CODING_CATEGORY_MASK_ISO_7_ELSE	(1 << CODING_CATEGORY_IDX_ISO_7_ELSE)
#define CODING_CATEGORY_MASK_ISO_8_ELSE	(1 << CODING_CATEGORY_IDX_ISO_8_ELSE)
#define CODING_CATEGORY_MASK_BIG5	(1 << CODING_CATEGORY_IDX_BIG5)
#define CODING_CATEGORY_MASK_BINARY	(1 << CODING_CATEGORY_IDX_BINARY)

/* This value is returned if detect_coding_mask () find nothing other
   than ASCII characters.  */
#define CODING_CATEGORY_MASK_ANY  	\
  (  CODING_CATEGORY_MASK_EMACS_MULE	\
   | CODING_CATEGORY_MASK_SJIS	  	\
   | CODING_CATEGORY_MASK_ISO_7	  	\
   | CODING_CATEGORY_MASK_ISO_8_1 	\
   | CODING_CATEGORY_MASK_ISO_8_2 	\
   | CODING_CATEGORY_MASK_ISO_7_ELSE	\
   | CODING_CATEGORY_MASK_ISO_8_ELSE	\
   | CODING_CATEGORY_MASK_BIG5)

/* Macros to decode or encode a character of JISX0208 in SJIS.  S1 and
   S2 are the 1st and 2nd position-codes of JISX0208 in SJIS coding
   system.  C1 and C2 are the 1st and 2nd position codes of Emacs'
   internal format.  */

#define DECODE_SJIS(s1, s2, c1, c2)		  	\
  do {						  	\
    if (s2 >= 0x9F)				  	\
      c1 = s1 * 2 - (s1 >= 0xE0 ? 0x160 : 0xE0),  	\
      c2 = s2 - 0x7E;				  	\
    else					  	\
      c1 = s1 * 2 - ((s1 >= 0xE0) ? 0x161 : 0xE1),	\
      c2 = s2 - ((s2 >= 0x7F) ? 0x20 : 0x1F);	  	\
  } while (0)

#define ENCODE_SJIS(c1, c2, s1, s2)			\
  do {							\
    if (c1 & 1)						\
      s1 = c1 / 2 + ((c1 < 0x5F) ? 0x71 : 0xB1),	\
      s2 = c2 + ((c2 >= 0x60) ? 0x20 : 0x1F);		\
    else						\
      s1 = c1 / 2 + ((c1 < 0x5F) ? 0x70 : 0xB0),	\
      s2 = c2 + 0x7E;					\
  } while (0)

/* Extern declarations.  */
extern int decode_coding (), encode_coding ();
extern int decoding_buffer_size (), encoding_buffer_size ();
extern int conversion_buffer_size;
extern char *conversion_buffer, *get_conversion_buffer ();
extern Lisp_Object Fcheck_coding_system ();
extern Lisp_Object Qcoding_system, Qeol_type, Qcoding_category_index;
extern Lisp_Object Qemacs_mule;
extern Lisp_Object Qbuffer_file_coding_system;
extern Lisp_Object Vcoding_category_list;

/* Mnemonic character to indicate each type of end-of-line.  */
extern int eol_mnemonic_unix, eol_mnemonic_dos, eol_mnemonic_mac;
/* Mnemonic character to indicate type of end-of-line is not yet decided.  */
extern int eol_mnemonic_undecided;

/* Table of coding-systems currently assigned to each coding-category.  */
extern Lisp_Object coding_category_table[CODING_CATEGORY_IDX_MAX];
/* Table of names of symbol for each coding-category.  */
extern char *coding_category_name[CODING_CATEGORY_IDX_MAX];

#ifdef emacs
extern Lisp_Object Qfile_coding_system;
extern Lisp_Object Qcall_process, Qcall_process_region, Qprocess_argument;
extern Lisp_Object Qstart_process, Qopen_network_stream;

/* Coding-system for reading files and receiving data from process.  */
extern Lisp_Object Vcoding_system_for_read;
/* Coding-system for writing files and sending data to process.  */
extern Lisp_Object Vcoding_system_for_write;
/* Coding-system actually used in the latest I/O.  */
extern Lisp_Object Vlast_coding_system_used;

/* Coding-system to be used for encoding terminal output.  This
   structure contains information of a coding-system specified by the
   function `set-terminal-coding-system'.  */
extern struct coding_system terminal_coding;

/* Coding system to be used to encode text for terminal display when
   terminal coding system is nil.  */
extern struct coding_system safe_terminal_coding;

/* Coding-system of what is sent from terminal keyboard.  This
   structure contains information of a coding-system specified by the
   function `set-keyboard-coding-system'.  */
extern struct coding_system keyboard_coding;

/* Default coding systems used for process I/O.  */
extern Lisp_Object Vdefault_process_coding_system;

#endif

#endif /* _CODING_H */
Commit	Line	Data
4ed46869	1	/* Header for coding system handler.
75c8c592 RS	2	Copyright (C) 1995, 1997 Electrotechnical Laboratory, JAPAN.
75c8c592 RS	3	Licensed to the Free Software Foundation.
4ed46869	4
369314dc KH	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.
4ed46869	11
369314dc KH	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.
4ed46869	16
369314dc KH	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. */
4ed46869 KH	21
	22	#ifndef _CODING_H
	23	#define _CODING_H
	24
	25	#ifndef _CCL_H
	26	#include "../src/ccl.h"
	27	#endif
	28
0ef69138	29	/* EMACS' INTERNAL FORMAT (emacs-mule) section */
4ed46869 KH	30
	31	/* All code (1-byte) of Emacs' internal format is classified into one
	32	of the followings. See also `charset.h'. */
	33	enum emacs_code_class_type
	34	{
	35	EMACS_control_code, /* Control codes in the range
	36	0x00..0x1F and 0x7F except for the
	37	following two codes. */
	38	EMACS_linefeed_code, /* 0x0A (linefeed) to denote
	39	end-of-line. */
	40	EMACS_carriage_return_code, /* 0x0D (carriage-return) to be used
	41	in selective display mode. */
	42	EMACS_ascii_code, /* ASCII characters. */
	43	EMACS_leading_code_composition, /* Leading code of a composite
	44	character. */
	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
	57	extern 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. */
	75	enum iso_code_class_type
	76	{
	77	ISO_control_code, /* Control codes in the range
	78	0x00..0x1F, 0x7F, and 0x80..0x9F,
	79	except for the following seven
	80	codes. */
	81	ISO_carriage_return, /* ISO_CODE_CR (0x0D) */
	82	ISO_shift_out, /* ISO_CODE_SO (0x0E) */
	83	ISO_shift_in, /* ISO_CODE_SI (0x0F) */
	84	ISO_single_shift_2_7, /* ISO_CODE_SS2_7 (0x19) */
	85	ISO_escape, /* ISO_CODE_SO (0x1B) */
	86	ISO_single_shift_2, /* ISO_CODE_SS2 (0x8E) */
	87	ISO_single_shift_3, /* ISO_CODE_SS3 (0x8F) */
	88	ISO_control_sequence_introducer, /* ISO_CODE_CSI (0x9B) */
	89	ISO_0x20_or_0x7F, /* Codes of the values 0x20 or 0x7F. */
	90	ISO_graphic_plane_0, /* Graphic codes in the range 0x21..0x7E. */
	91	ISO_0xA0_or_0xFF, /* Codes of the values 0xA0 or 0xFF. */
	92	ISO_graphic_plane_1 /* Graphic codes in the range 0xA1..0xFE. */
	93	};
94
95	/** The macros CODING_FLAG_ISO_XXX defines a flag bit of the `flags'
96	element in the structure `coding_system'. This information is used
97	while encoding a text to ISO2022. **/
98
99	/* If set, produce short-form designation sequence (e.g. ESC $ A)
100	instead of long-form sequence (e.g. ESC $ ( A). */
101	#define CODING_FLAG_ISO_SHORT_FORM 0x0001
102
103	/* If set, reset graphic planes and registers at end-of-line to the
104	initial state. */
105	#define CODING_FLAG_ISO_RESET_AT_EOL 0x0002
106
107	/* If set, reset graphic planes and registers before any control
108	characters to the initial state. */
109	#define CODING_FLAG_ISO_RESET_AT_CNTL 0x0004
110
111	/* If set, encode by 7-bit environment. */
112	#define CODING_FLAG_ISO_SEVEN_BITS 0x0008
113
114	/* If set, use locking-shift function. */
115	#define CODING_FLAG_ISO_LOCKING_SHIFT 0x0010
116
117	/* If set, use single-shift function. Overwrite
118	CODING_FLAG_ISO_LOCKING_SHIFT. */
119	#define CODING_FLAG_ISO_SINGLE_SHIFT 0x0020
120
121	/* If set, designate JISX0201-Roman instead of ASCII. */
122	#define CODING_FLAG_ISO_USE_ROMAN 0x0040
123
124	/* If set, designate JISX0208-1978 instead of JISX0208-1983. */
125	#define CODING_FLAG_ISO_USE_OLDJIS 0x0080
126
127	/* If set, do not produce ISO6429's direction specifying sequence. */
128	#define CODING_FLAG_ISO_NO_DIRECTION 0x0100
129
8ddb35b2 KH	130	/* If set, assume designation states are reset at beginning of line on
	131	output. */
	132	#define CODING_FLAG_ISO_INIT_AT_BOL 0x0200
	133
	134	/* If set, designation sequence should be placed at beginning of line
	135	on output. */
	136	#define CODING_FLAG_ISO_DESIGNATE_AT_BOL 0x0400
	137
fbaa2ed9 KH	138	/* If set, do not encode unexpected charactes on output. */
	139	#define CODING_FLAG_ISO_SAFE 0x0800
	140
	141	/* A character to be produced on output if encoding of the original
	142	character is prohibited by CODING_FLAG_ISO_SAFE. */
	143	#define CODING_INHIBIT_CHARACTER_SUBSTITUTION 077 /* `?' */
	144
4ed46869 KH	145	/* Structure of the field `spec.iso2022' in the structure `coding_system'. */
	146	struct iso2022_spec
	147	{
	148	/* The current graphic register invoked to each graphic plane. */
	149	int current_invocation[2];
	150
	151	/* The current charset designated to each graphic register. */
	152	int current_designation[4];
	153
	154	/* A charset initially designated to each graphic register. */
	155	int initial_designation[4];
	156
	157	/* A graphic register to which each charset should be designated. */
da30d5b1	158	unsigned char requested_designation[MAX_CHARSET + 1];
4ed46869 KH	159
	160	/* Set to 1 temporarily only when graphic register 2 or 3 is invoked
	161	by single-shift while encoding. */
	162	int single_shifting;
8ddb35b2 KH	163
	164	/* Set to 1 temporarily only when processing at beginning of line. */
	165	int bol;
4ed46869 KH	166	};
	167
	168	/* Macros to access each field in the structure `spec.iso2022'. */
	169	#define CODING_SPEC_ISO_INVOCATION(coding, plane) \
	170	coding->spec.iso2022.current_invocation[plane]
	171	#define CODING_SPEC_ISO_DESIGNATION(coding, reg) \
	172	coding->spec.iso2022.current_designation[reg]
	173	#define CODING_SPEC_ISO_INITIAL_DESIGNATION(coding, reg) \
	174	coding->spec.iso2022.initial_designation[reg]
	175	#define CODING_SPEC_ISO_REQUESTED_DESIGNATION(coding, charset) \
	176	coding->spec.iso2022.requested_designation[charset]
4ed46869 KH	177	#define CODING_SPEC_ISO_SINGLE_SHIFTING(coding) \
4ed46869 KH	178	coding->spec.iso2022.single_shifting
8ddb35b2 KH	179	#define CODING_SPEC_ISO_BOL(coding) \
8ddb35b2 KH	180	coding->spec.iso2022.bol
4ed46869	181
da30d5b1 KH	182	/* A value which may appear in
	183	coding->spec.iso2022.requested_designation indicating that the
	184	corresponding charset does not request any graphic register to be
	185	designated. */
	186	#define CODING_SPEC_ISO_NO_REQUESTED_DESIGNATION 4
	187
4ed46869 KH	188	/* Return a charset which is currently designated to the graphic plane
4ed46869 KH	189	PLANE in the coding-system CODING. */
ceb58510 KH	190	#define CODING_SPEC_ISO_PLANE_CHARSET(coding, plane) \
	191	((CODING_SPEC_ISO_INVOCATION (coding, plane) < 0) \
	192	? -1 \
	193	: CODING_SPEC_ISO_DESIGNATION (coding, \
	194	CODING_SPEC_ISO_INVOCATION (coding, plane)))
4ed46869 KH	195
	196	/* BIG5 section */
	197
	198	/* Macros to denote each type of BIG5 coding system. */
	199	#define CODING_FLAG_BIG5_HKU 0x00 /* BIG5-HKU is one of variants of
	200	BIG5 developed by Hong Kong
	201	University. */
	202	#define CODING_FLAG_BIG5_ETEN 0x01 /* BIG5_ETen is one of variants
	203	of BIG5 developed by the
	204	company ETen in Taiwan. */
	205
	206	/* GENERAL section */
	207
	208	/* Types of coding system. */
	209	enum coding_type
	210	{
	211	coding_type_no_conversion, /* A coding system which requires no
	212	conversion for reading and writing
	213	including end-of-line format. */
0ef69138	214	coding_type_emacs_mule, /* A coding system used in Emacs'
4ed46869 KH	215	buffer and string. Requires no
	216	conversion for reading and writing
	217	except for end-of-line format. */
0ef69138	218	coding_type_undecided, /* A coding system which requires
4ed46869 KH	219	automatic detection of a real
	220	coding system. */
	221	coding_type_sjis, /* SJIS coding system for Japanese. */
	222	coding_type_iso2022, /* Any coding system of ISO2022
	223	variants. */
	224	coding_type_big5, /* BIG5 coding system for Chinese. */
	225	coding_type_ccl /* The coding system of which decoder
	226	and encoder are written in CCL. */
	227	};
	228
	229	/* Formats of end-of-line. */
	230	#define CODING_EOL_LF 0 /* Line-feed only, same as Emacs'
	231	internal format. */
	232	#define CODING_EOL_CRLF 1 /* Sequence of carriage-return and
	233	line-feed. */
	234	#define CODING_EOL_CR 2 /* Carriage-return only. */
0ef69138	235	#define CODING_EOL_UNDECIDED 3 /* This value is used to denote the
4ed46869 KH	236	eol-type is not yet decided. */
	237
	238	/* Character composition status while encoding/decoding. */
	239	#define COMPOSING_NO 0 /* not composing */
	240	#define COMPOSING_WITH_RULE_HEAD 1 /* 1st char of with-rule composing follow */
	241	#define COMPOSING_NO_RULE_HEAD 2 /* 1st char of no-rule composing follow */
	242	#define COMPOSING_WITH_RULE_TAIL 3 /* Nth char of with-rule composing follow */
	243	#define COMPOSING_NO_RULE_TAIL 4 /* Nth char of no-rule composing follow */
	244	#define COMPOSING_WITH_RULE_RULE 5 /* composition rule follow */
	245
	246	/* 1 iff composing. */
	247	#define COMPOSING_P(composing) (composing)
	248	/* 1 iff 1st char of composing element follows. */
	249	#define COMPOSING_HEAD_P(composing) \
	250	((composing) && (composing) <= COMPOSING_NO_RULE_HEAD)
	251	/* 1 iff composing with embeded composition rule. */
	252	#define COMPOSING_WITH_RULE_P(composing) ((composing) & 1)
	253
	254	struct coding_system
	255	{
	256	/* Type of the coding system. */
	257	enum coding_type type;
	258
	259	/* If the coding system requires specific code to be attached at the
	260	tail of converted text, this value should be set to `1'. */
	261	int require_flushing;
	262
	263	/* Flag bits of the coding system. The meaning of each bit depends
	264	on the type of the coding system. */
	265	unsigned int flags;
	266
	267	/* Type of end-of-line format (LF, CRLF, or CR) of the coding system. */
	268	int eol_type;
	269
	270	/* Non-zero means that the current source text is the last block of the
	271	whole text to be converted. */
	272	int last_block;
	273
	274	/* Non-zero means that characters are being composed currently while
	275	decoding or encoding. See macros COMPOSING_XXXX above for the
	276	meaing of each non-zero value. */
	277	int composing;
	278
	279	/* 0 (left-to-right) or 1 (right-to-left): the direction of the text
	280	being processed currently. */
	281	int direction;
	282
	283	/* Non-zero means that the current source text is in a buffer which
	284	enables selective display. */
	285	int selective;
	286
	287	/* Detailed information specific to each type of coding system. */
	288	union spec
	289	{
	290	struct iso2022_spec iso2022;
	291	struct ccl_spec ccl; /* Defined in ccl.h. */
	292	} spec;
	293
	294	/* Backward pointer to the Lisp symbol of the coding system. */
	295	Lisp_Object symbol;
	296
	297	/* Lisp function (symbol) to be called after decoding to do
	298	additional conversion. */
	299	Lisp_Object post_read_conversion;
300
301	/* Lisp function (symbol) to be called before encoding to do
302	additional conversion. */
303	Lisp_Object pre_write_conversion;
304
e8cafdc1 KH	305	/* Character unification tables to look up, or nil. */
	306	Lisp_Object character_unification_table_for_decode;
	307	Lisp_Object character_unification_table_for_encode;
ceb58510	308
4ed46869 KH	309	/* Carryover yielded by decoding/encoding incomplete source. No
	310	coding-system yields more than 7-byte of carryover. This does
	311	not include a text which is not processed because of short of
	312	output buffer. */
	313	char carryover[8];
	314
	315	/* Actual data length in the above array. */
	316	int carryover_size;
	317	};
	318
4dad0cba KH	319	/* Return 1 if coding system CODING never requires any code conversion. */
	320	#define CODING_REQUIRE_NO_CONVERSION(coding) \
	321	(((coding)->type == coding_type_no_conversion \
	322	\|\| (coding)->type == coding_type_emacs_mule) \
	323	&& (coding)->eol_type == CODING_EOL_LF)
	324
	325	/* Return 1 if coding system CODING may not require code conversion. */
	326	#define CODING_MAY_REQUIRE_NO_CONVERSION(coding) \
	327	(((coding)->type == coding_type_no_conversion \
	328	\|\| (coding)->type == coding_type_emacs_mule \
	329	\|\| (coding)->type == coding_type_undecided) \
	330	&& ((coding)->eol_type == CODING_EOL_LF \
	331	\|\| (coding)->eol_type == CODING_EOL_UNDECIDED))
4ed46869 KH	332
4ed46869 KH	333	/* Index for each coding category in `coding_category_table' */
0ef69138	334	#define CODING_CATEGORY_IDX_EMACS_MULE 0
4ed46869 KH	335	#define CODING_CATEGORY_IDX_SJIS 1
	336	#define CODING_CATEGORY_IDX_ISO_7 2
	337	#define CODING_CATEGORY_IDX_ISO_8_1 3
	338	#define CODING_CATEGORY_IDX_ISO_8_2 4
a38ede41 KH	339	#define CODING_CATEGORY_IDX_ISO_7_ELSE 5
	340	#define CODING_CATEGORY_IDX_ISO_8_ELSE 6
	341	#define CODING_CATEGORY_IDX_BIG5 7
	342	#define CODING_CATEGORY_IDX_BINARY 8
	343	#define CODING_CATEGORY_IDX_MAX 9
4ed46869 KH	344
	345	/* Definitions of flag bits returned by the function
	346	detect_coding_mask (). */
0ef69138	347	#define CODING_CATEGORY_MASK_EMACS_MULE (1 << CODING_CATEGORY_IDX_EMACS_MULE)
4ed46869 KH	348	#define CODING_CATEGORY_MASK_SJIS (1 << CODING_CATEGORY_IDX_SJIS)
	349	#define CODING_CATEGORY_MASK_ISO_7 (1 << CODING_CATEGORY_IDX_ISO_7)
	350	#define CODING_CATEGORY_MASK_ISO_8_1 (1 << CODING_CATEGORY_IDX_ISO_8_1)
	351	#define CODING_CATEGORY_MASK_ISO_8_2 (1 << CODING_CATEGORY_IDX_ISO_8_2)
a38ede41 KH	352	#define CODING_CATEGORY_MASK_ISO_7_ELSE (1 << CODING_CATEGORY_IDX_ISO_7_ELSE)
a38ede41 KH	353	#define CODING_CATEGORY_MASK_ISO_8_ELSE (1 << CODING_CATEGORY_IDX_ISO_8_ELSE)
4ed46869	354	#define CODING_CATEGORY_MASK_BIG5 (1 << CODING_CATEGORY_IDX_BIG5)
1f312d8a	355	#define CODING_CATEGORY_MASK_BINARY (1 << CODING_CATEGORY_IDX_BINARY)
4ed46869 KH	356
	357	/* This value is returned if detect_coding_mask () find nothing other
	358	than ASCII characters. */
	359	#define CODING_CATEGORY_MASK_ANY \
0ef69138	360	( CODING_CATEGORY_MASK_EMACS_MULE \
4ed46869 KH	361	\| CODING_CATEGORY_MASK_SJIS \
	362	\| CODING_CATEGORY_MASK_ISO_7 \
	363	\| CODING_CATEGORY_MASK_ISO_8_1 \
	364	\| CODING_CATEGORY_MASK_ISO_8_2 \
a38ede41 KH	365	\| CODING_CATEGORY_MASK_ISO_7_ELSE \
a38ede41 KH	366	\| CODING_CATEGORY_MASK_ISO_8_ELSE \
4ed46869 KH	367	\| CODING_CATEGORY_MASK_BIG5)
	368
	369	/* Macros to decode or encode a character of JISX0208 in SJIS. S1 and
	370	S2 are the 1st and 2nd position-codes of JISX0208 in SJIS coding
	371	system. C1 and C2 are the 1st and 2nd position codes of Emacs'
	372	internal format. */
	373
	374	#define DECODE_SJIS(s1, s2, c1, c2) \
	375	do { \
	376	if (s2 >= 0x9F) \
	377	c1 = s1 * 2 - (s1 >= 0xE0 ? 0x160 : 0xE0), \
	378	c2 = s2 - 0x7E; \
	379	else \
	380	c1 = s1 * 2 - ((s1 >= 0xE0) ? 0x161 : 0xE1), \
	381	c2 = s2 - ((s2 >= 0x7F) ? 0x20 : 0x1F); \
	382	} while (0)
	383
	384	#define ENCODE_SJIS(c1, c2, s1, s2) \
	385	do { \
	386	if (c1 & 1) \
	387	s1 = c1 / 2 + ((c1 < 0x5F) ? 0x71 : 0xB1), \
	388	s2 = c2 + ((c2 >= 0x60) ? 0x20 : 0x1F); \
	389	else \
	390	s1 = c1 / 2 + ((c1 < 0x5F) ? 0x70 : 0xB0), \
	391	s2 = c2 + 0x7E; \
	392	} while (0)
	393
	394	/* Extern declarations. */
	395	extern int decode_coding (), encode_coding ();
	396	extern int decoding_buffer_size (), encoding_buffer_size ();
	397	extern int conversion_buffer_size;
	398	extern char conversion_buffer, get_conversion_buffer ();
	399	extern Lisp_Object Fcheck_coding_system ();
	400	extern Lisp_Object Qcoding_system, Qeol_type, Qcoding_category_index;
3f356e65	401	extern Lisp_Object Qemacs_mule;
4ed46869 KH	402	extern Lisp_Object Qbuffer_file_coding_system;
	403	extern Lisp_Object Vcoding_category_list;
	404
	405	/* Mnemonic character to indicate each type of end-of-line. */
	406	extern int eol_mnemonic_unix, eol_mnemonic_dos, eol_mnemonic_mac;
	407	/* Mnemonic character to indicate type of end-of-line is not yet decided. */
	408	extern int eol_mnemonic_undecided;
	409
	410	/* Table of coding-systems currently assigned to each coding-category. */
	411	extern Lisp_Object coding_category_table[CODING_CATEGORY_IDX_MAX];
	412	/* Table of names of symbol for each coding-category. */
	413	extern char *coding_category_name[CODING_CATEGORY_IDX_MAX];
	414
	415	#ifdef emacs
	416	extern Lisp_Object Qfile_coding_system;
	417	extern Lisp_Object Qcall_process, Qcall_process_region, Qprocess_argument;
	418	extern Lisp_Object Qstart_process, Qopen_network_stream;
	419
	420	/* Coding-system for reading files and receiving data from process. */
	421	extern Lisp_Object Vcoding_system_for_read;
	422	/* Coding-system for writing files and sending data to process. */
	423	extern Lisp_Object Vcoding_system_for_write;
	424	/* Coding-system actually used in the latest I/O. */
	425	extern Lisp_Object Vlast_coding_system_used;
	426
	427	/* Coding-system to be used for encoding terminal output. This
	428	structure contains information of a coding-system specified by the
	429	function `set-terminal-coding-system'. */
	430	extern struct coding_system terminal_coding;
	431
fbaa2ed9 KH	432	/* Coding system to be used to encode text for terminal display when
	433	terminal coding system is nil. */
	434	extern struct coding_system safe_terminal_coding;
	435
4ed46869 KH	436	/* Coding-system of what is sent from terminal keyboard. This
	437	structure contains information of a coding-system specified by the
	438	function `set-keyboard-coding-system'. */
	439	extern struct coding_system keyboard_coding;
	440
a5825a24 KH	441	/* Default coding systems used for process I/O. */
a5825a24 KH	442	extern Lisp_Object Vdefault_process_coding_system;
4ed46869 KH	443
	444	#endif
	445
	446	#endif /* _CODING_H */