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

/* Header for coding system handler.
   Ver.1.0

   Copyright (C) 1995 Free Software Foundation, Inc.
   Copyright (C) 1995 Electrotechnical Laboratory, JAPAN.

   This program 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.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#ifndef _CODING_H
#define _CODING_H

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

/*** EMACS' INTERNAL FORMAT 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

/* 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.  */
  int requested_designation[MAX_CHARSET];

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

/* 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]

/* Set to 1 temporarily only when encoding a character with
   single-shift function.  */
#define CODING_SPEC_ISO_SINGLE_SHIFTING(coding) \
  coding->spec.iso2022.single_shifting

/* 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_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_internal,	/* A coding system used in Emacs'
				   buffer and string.  Requires no
				   conversion for reading and writing
				   except for end-of-line format.  */
    coding_type_automatic,	/* 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_AUTOMATIC 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;

  /* 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 the coding-system CODING requires conversion of
   representation of a visible character (text).  */
#define CODING_REQUIRE_TEXT_CONVERSION(coding)	\
  ((coding)->type != coding_type_no_conversion  	\
   && (coding)->type != coding_type_internal)

/* Return 1 if the coding-system CODING requires conversion of the
   format of end-of-line.  */
#define CODING_REQUIRE_EOL_CONVERSION(coding)	\
  ((coding)->eol_type != CODING_EOL_AUTOMATIC  	\
   && (coding)->eol_type != CODING_EOL_LF)

/* Return 1 if the coding-system CODING requires some conversion.  */
#define CODING_REQUIRE_CONVERSION(coding)  	\
  (CODING_REQUIRE_TEXT_CONVERSION (coding) 	\
   || CODING_REQUIRE_EOL_CONVERSION (coding))

/* Index for each coding category in `coding_category_table' */
#define CODING_CATEGORY_IDX_INTERNAL	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_ELSE	5
#define CODING_CATEGORY_IDX_BIG5	6
#define CODING_CATEGORY_IDX_BINARY	7
#define CODING_CATEGORY_IDX_MAX		8

/* Definitions of flag bits returned by the function
   detect_coding_mask ().  */
#define CODING_CATEGORY_MASK_INTERNAL	(1 << CODING_CATEGORY_IDX_INTERNAL)
#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_ELSE	(1 << CODING_CATEGORY_IDX_ISO_ELSE)
#define CODING_CATEGORY_MASK_BIG5	(1 << CODING_CATEGORY_IDX_BIG5)

/* This value is returned if detect_coding_mask () find nothing other
   than ASCII characters.  */
#define CODING_CATEGORY_MASK_ANY  	\
  (  CODING_CATEGORY_MASK_INTERNAL	\
   | 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_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 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 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;

extern Lisp_Object Vcoding_system_alist;

#endif

#endif /* _CODING_H */
Commit	Line	Data
4ed46869 KH	1	/* Header for coding system handler.
	2	Ver.1.0
	3
	4	Copyright (C) 1995 Free Software Foundation, Inc.
	5	Copyright (C) 1995 Electrotechnical Laboratory, JAPAN.
	6
	7	This program 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	This program 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 this program; if not, write to the Free Software
	19	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
	20
	21	#ifndef _CODING_H
	22	#define _CODING_H
	23
	24	#ifndef _CCL_H
	25	#include "../src/ccl.h"
	26	#endif
	27
	28	/* EMACS' INTERNAL FORMAT section */
	29
	30	/* All code (1-byte) of Emacs' internal format is classified into one
	31	of the followings. See also `charset.h'. */
	32	enum emacs_code_class_type
	33	{
	34	EMACS_control_code, /* Control codes in the range
	35	0x00..0x1F and 0x7F except for the
	36	following two codes. */
	37	EMACS_linefeed_code, /* 0x0A (linefeed) to denote
	38	end-of-line. */
	39	EMACS_carriage_return_code, /* 0x0D (carriage-return) to be used
	40	in selective display mode. */
	41	EMACS_ascii_code, /* ASCII characters. */
	42	EMACS_leading_code_composition, /* Leading code of a composite
	43	character. */
	44	EMACS_leading_code_2, /* Base leading code of official
	45	TYPE9N character. */
	46	EMACS_leading_code_3, /* Base leading code of private TYPE9N
	47	or official TYPE9Nx9N character. */
	48	EMACS_leading_code_4, /* Base leading code of private
	49	TYPE9Nx9N character. */
	50	EMACS_invalid_code /* Invalid code, i.e. a base leading
	51	code not yet assigned to any
	52	charset, or a code of the range
	53	0xA0..0xFF. */
	54	};
	55
	56	extern enum emacs_code_class_type emacs_code_class[256];
	57
	58	/* ISO2022 section */
	59
	60	/* Macros to define code of control characters for ISO2022's functions. */
	61	/* code / / function */
	62	#define ISO_CODE_LF 0x0A /* line-feed */
	63	#define ISO_CODE_CR 0x0D /* carriage-return */
	64	#define ISO_CODE_SO 0x0E /* shift-out */
65	#define ISO_CODE_SI 0x0F /* shift-in */
66	#define ISO_CODE_SS2_7 0x19 /* single-shift-2 for 7-bit code */
67	#define ISO_CODE_ESC 0x1B /* escape */
68	#define ISO_CODE_SS2 0x8E /* single-shift-2 */
69	#define ISO_CODE_SS3 0x8F /* single-shift-3 */
70	#define ISO_CODE_CSI 0x9B /* control-sequence-introduce */
71
72	/* All code (1-byte) of ISO2022 is classified into one of the
73	followings. */
74	enum iso_code_class_type
75	{
76	ISO_control_code, /* Control codes in the range
77	0x00..0x1F, 0x7F, and 0x80..0x9F,
78	except for the following seven
79	codes. */
80	ISO_carriage_return, /* ISO_CODE_CR (0x0D) */
81	ISO_shift_out, /* ISO_CODE_SO (0x0E) */
82	ISO_shift_in, /* ISO_CODE_SI (0x0F) */
83	ISO_single_shift_2_7, /* ISO_CODE_SS2_7 (0x19) */
84	ISO_escape, /* ISO_CODE_SO (0x1B) */
85	ISO_single_shift_2, /* ISO_CODE_SS2 (0x8E) */
86	ISO_single_shift_3, /* ISO_CODE_SS3 (0x8F) */
87	ISO_control_sequence_introducer, /* ISO_CODE_CSI (0x9B) */
88	ISO_0x20_or_0x7F, /* Codes of the values 0x20 or 0x7F. */
89	ISO_graphic_plane_0, /* Graphic codes in the range 0x21..0x7E. */
90	ISO_0xA0_or_0xFF, /* Codes of the values 0xA0 or 0xFF. */
91	ISO_graphic_plane_1 /* Graphic codes in the range 0xA1..0xFE. */
92	};
93
94	/** The macros CODING_FLAG_ISO_XXX defines a flag bit of the `flags'
95	element in the structure `coding_system'. This information is used
96	while encoding a text to ISO2022. **/
97
98	/* If set, produce short-form designation sequence (e.g. ESC $ A)
99	instead of long-form sequence (e.g. ESC $ ( A). */
100	#define CODING_FLAG_ISO_SHORT_FORM 0x0001
101
102	/* If set, reset graphic planes and registers at end-of-line to the
103	initial state. */
104	#define CODING_FLAG_ISO_RESET_AT_EOL 0x0002
105
106	/* If set, reset graphic planes and registers before any control
107	characters to the initial state. */
108	#define CODING_FLAG_ISO_RESET_AT_CNTL 0x0004
109
110	/* If set, encode by 7-bit environment. */
111	#define CODING_FLAG_ISO_SEVEN_BITS 0x0008
112
113	/* If set, use locking-shift function. */
114	#define CODING_FLAG_ISO_LOCKING_SHIFT 0x0010
115
116	/* If set, use single-shift function. Overwrite
117	CODING_FLAG_ISO_LOCKING_SHIFT. */
118	#define CODING_FLAG_ISO_SINGLE_SHIFT 0x0020
119
120	/* If set, designate JISX0201-Roman instead of ASCII. */
121	#define CODING_FLAG_ISO_USE_ROMAN 0x0040
122
123	/* If set, designate JISX0208-1978 instead of JISX0208-1983. */
124	#define CODING_FLAG_ISO_USE_OLDJIS 0x0080
125
126	/* If set, do not produce ISO6429's direction specifying sequence. */
127	#define CODING_FLAG_ISO_NO_DIRECTION 0x0100
128
129	/* Structure of the field `spec.iso2022' in the structure `coding_system'. */
130	struct iso2022_spec
131	{
132	/* The current graphic register invoked to each graphic plane. */
133	int current_invocation[2];
134
135	/* The current charset designated to each graphic register. */
136	int current_designation[4];
137
138	/* A charset initially designated to each graphic register. */
139	int initial_designation[4];
140
141	/* A graphic register to which each charset should be designated. */
142	int requested_designation[MAX_CHARSET];
143
144	/* Set to 1 temporarily only when graphic register 2 or 3 is invoked
145	by single-shift while encoding. */
146	int single_shifting;
147	};
148
149	/* Macros to access each field in the structure `spec.iso2022'. */
150	#define CODING_SPEC_ISO_INVOCATION(coding, plane) \
151	coding->spec.iso2022.current_invocation[plane]
152	#define CODING_SPEC_ISO_DESIGNATION(coding, reg) \
153	coding->spec.iso2022.current_designation[reg]
154	#define CODING_SPEC_ISO_INITIAL_DESIGNATION(coding, reg) \
155	coding->spec.iso2022.initial_designation[reg]
156	#define CODING_SPEC_ISO_REQUESTED_DESIGNATION(coding, charset) \
157	coding->spec.iso2022.requested_designation[charset]
158
159	/* Set to 1 temporarily only when encoding a character with
160	single-shift function. */
161	#define CODING_SPEC_ISO_SINGLE_SHIFTING(coding) \
162	coding->spec.iso2022.single_shifting
163
164	/* Return a charset which is currently designated to the graphic plane
165	PLANE in the coding-system CODING. */
166	#define CODING_SPEC_ISO_PLANE_CHARSET(coding, plane) \
167	CODING_SPEC_ISO_DESIGNATION \
168	(coding, CODING_SPEC_ISO_INVOCATION (coding, plane))
169
170	/* BIG5 section */
171
172	/* Macros to denote each type of BIG5 coding system. */
173	#define CODING_FLAG_BIG5_HKU 0x00 /* BIG5-HKU is one of variants of
174	BIG5 developed by Hong Kong
175	University. */
176	#define CODING_FLAG_BIG5_ETEN 0x01 /* BIG5_ETen is one of variants
177	of BIG5 developed by the
178	company ETen in Taiwan. */
179
180	/* GENERAL section */
181
182	/* Types of coding system. */
183	enum coding_type
184	{
185	coding_type_no_conversion, /* A coding system which requires no
186	conversion for reading and writing
187	including end-of-line format. */
188	coding_type_internal, /* A coding system used in Emacs'
189	buffer and string. Requires no
190	conversion for reading and writing
191	except for end-of-line format. */
192	coding_type_automatic, /* A coding system which requires
193	automatic detection of a real
194	coding system. */
195	coding_type_sjis, /* SJIS coding system for Japanese. */
196	coding_type_iso2022, /* Any coding system of ISO2022
197	variants. */
198	coding_type_big5, /* BIG5 coding system for Chinese. */
199	coding_type_ccl /* The coding system of which decoder
200	and encoder are written in CCL. */
201	};
202
203	/* Formats of end-of-line. */
204	#define CODING_EOL_LF 0 /* Line-feed only, same as Emacs'
205	internal format. */
206	#define CODING_EOL_CRLF 1 /* Sequence of carriage-return and
207	line-feed. */
208	#define CODING_EOL_CR 2 /* Carriage-return only. */
209	#define CODING_EOL_AUTOMATIC 3 /* This value is used to denote the
210	eol-type is not yet decided. */
211
212	/* Character composition status while encoding/decoding. */
213	#define COMPOSING_NO 0 /* not composing */
214	#define COMPOSING_WITH_RULE_HEAD 1 /* 1st char of with-rule composing follow */
215	#define COMPOSING_NO_RULE_HEAD 2 /* 1st char of no-rule composing follow */
216	#define COMPOSING_WITH_RULE_TAIL 3 /* Nth char of with-rule composing follow */
217	#define COMPOSING_NO_RULE_TAIL 4 /* Nth char of no-rule composing follow */
218	#define COMPOSING_WITH_RULE_RULE 5 /* composition rule follow */
219
220	/* 1 iff composing. */
221	#define COMPOSING_P(composing) (composing)
222	/* 1 iff 1st char of composing element follows. */
223	#define COMPOSING_HEAD_P(composing) \
224	((composing) && (composing) <= COMPOSING_NO_RULE_HEAD)
225	/* 1 iff composing with embeded composition rule. */
226	#define COMPOSING_WITH_RULE_P(composing) ((composing) & 1)
227
228	struct coding_system
229	{
230	/* Type of the coding system. */
231	enum coding_type type;
232
233	/* If the coding system requires specific code to be attached at the
234	tail of converted text, this value should be set to `1'. */
235	int require_flushing;
236
237	/* Flag bits of the coding system. The meaning of each bit depends
238	on the type of the coding system. */
239	unsigned int flags;
240
241	/* Type of end-of-line format (LF, CRLF, or CR) of the coding system. */
242	int eol_type;
243
244	/* Non-zero means that the current source text is the last block of the
245	whole text to be converted. */
246	int last_block;
247
248	/* Non-zero means that characters are being composed currently while
249	decoding or encoding. See macros COMPOSING_XXXX above for the
250	meaing of each non-zero value. */
251	int composing;
252
253	/* 0 (left-to-right) or 1 (right-to-left): the direction of the text
254	being processed currently. */
255	int direction;
256
257	/* Non-zero means that the current source text is in a buffer which
258	enables selective display. */
259	int selective;
260
261	/* Detailed information specific to each type of coding system. */
262	union spec
263	{
264	struct iso2022_spec iso2022;
265	struct ccl_spec ccl; /* Defined in ccl.h. */
266	} spec;
267
268	/* Backward pointer to the Lisp symbol of the coding system. */
269	Lisp_Object symbol;
270
271	/* Lisp function (symbol) to be called after decoding to do
272	additional conversion. */
273	Lisp_Object post_read_conversion;
274
275	/* Lisp function (symbol) to be called before encoding to do
276	additional conversion. */
277	Lisp_Object pre_write_conversion;
278
279	/* Carryover yielded by decoding/encoding incomplete source. No
280	coding-system yields more than 7-byte of carryover. This does
281	not include a text which is not processed because of short of
282	output buffer. */
283	char carryover[8];
284
285	/* Actual data length in the above array. */
286	int carryover_size;
287	};
288
289	/* Return 1 if the coding-system CODING requires conversion of
290	representation of a visible character (text). */
291	#define CODING_REQUIRE_TEXT_CONVERSION(coding) \
292	((coding)->type != coding_type_no_conversion \
293	&& (coding)->type != coding_type_internal)
294
295	/* Return 1 if the coding-system CODING requires conversion of the
296	format of end-of-line. */
297	#define CODING_REQUIRE_EOL_CONVERSION(coding) \
298	((coding)->eol_type != CODING_EOL_AUTOMATIC \
299	&& (coding)->eol_type != CODING_EOL_LF)
300
301	/* Return 1 if the coding-system CODING requires some conversion. */
302	#define CODING_REQUIRE_CONVERSION(coding) \
303	(CODING_REQUIRE_TEXT_CONVERSION (coding) \
304	\|\| CODING_REQUIRE_EOL_CONVERSION (coding))
305
306	/* Index for each coding category in `coding_category_table' */
307	#define CODING_CATEGORY_IDX_INTERNAL 0
308	#define CODING_CATEGORY_IDX_SJIS 1
309	#define CODING_CATEGORY_IDX_ISO_7 2
310	#define CODING_CATEGORY_IDX_ISO_8_1 3
311	#define CODING_CATEGORY_IDX_ISO_8_2 4
312	#define CODING_CATEGORY_IDX_ISO_ELSE 5
313	#define CODING_CATEGORY_IDX_BIG5 6
314	#define CODING_CATEGORY_IDX_BINARY 7
315	#define CODING_CATEGORY_IDX_MAX 8
316
317	/* Definitions of flag bits returned by the function
318	detect_coding_mask (). */
319	#define CODING_CATEGORY_MASK_INTERNAL (1 << CODING_CATEGORY_IDX_INTERNAL)
320	#define CODING_CATEGORY_MASK_SJIS (1 << CODING_CATEGORY_IDX_SJIS)
321	#define CODING_CATEGORY_MASK_ISO_7 (1 << CODING_CATEGORY_IDX_ISO_7)
322	#define CODING_CATEGORY_MASK_ISO_8_1 (1 << CODING_CATEGORY_IDX_ISO_8_1)
323	#define CODING_CATEGORY_MASK_ISO_8_2 (1 << CODING_CATEGORY_IDX_ISO_8_2)
324	#define CODING_CATEGORY_MASK_ISO_ELSE (1 << CODING_CATEGORY_IDX_ISO_ELSE)
325	#define CODING_CATEGORY_MASK_BIG5 (1 << CODING_CATEGORY_IDX_BIG5)
326
327	/* This value is returned if detect_coding_mask () find nothing other
328	than ASCII characters. */
329	#define CODING_CATEGORY_MASK_ANY \
330	( CODING_CATEGORY_MASK_INTERNAL \
331	\| CODING_CATEGORY_MASK_SJIS \
332	\| CODING_CATEGORY_MASK_ISO_7 \
333	\| CODING_CATEGORY_MASK_ISO_8_1 \
334	\| CODING_CATEGORY_MASK_ISO_8_2 \
335	\| CODING_CATEGORY_MASK_ISO_ELSE \
336	\| CODING_CATEGORY_MASK_BIG5)
337
338	/* Macros to decode or encode a character of JISX0208 in SJIS. S1 and
339	S2 are the 1st and 2nd position-codes of JISX0208 in SJIS coding
340	system. C1 and C2 are the 1st and 2nd position codes of Emacs'
341	internal format. */
342
343	#define DECODE_SJIS(s1, s2, c1, c2) \
344	do { \
345	if (s2 >= 0x9F) \
346	c1 = s1 * 2 - (s1 >= 0xE0 ? 0x160 : 0xE0), \
347	c2 = s2 - 0x7E; \
348	else \
349	c1 = s1 * 2 - ((s1 >= 0xE0) ? 0x161 : 0xE1), \
350	c2 = s2 - ((s2 >= 0x7F) ? 0x20 : 0x1F); \
351	} while (0)
352
353	#define ENCODE_SJIS(c1, c2, s1, s2) \
354	do { \
355	if (c1 & 1) \
356	s1 = c1 / 2 + ((c1 < 0x5F) ? 0x71 : 0xB1), \
357	s2 = c2 + ((c2 >= 0x60) ? 0x20 : 0x1F); \
358	else \
359	s1 = c1 / 2 + ((c1 < 0x5F) ? 0x70 : 0xB0), \
360	s2 = c2 + 0x7E; \
361	} while (0)
362
363	/* Extern declarations. */
364	extern int decode_coding (), encode_coding ();
365	extern int decoding_buffer_size (), encoding_buffer_size ();
366	extern int conversion_buffer_size;
367	extern char conversion_buffer, get_conversion_buffer ();
368	extern Lisp_Object Fcheck_coding_system ();
369	extern Lisp_Object Qcoding_system, Qeol_type, Qcoding_category_index;
370	extern Lisp_Object Qbuffer_file_coding_system;
371	extern Lisp_Object Vcoding_category_list;
372
373	/* Mnemonic character to indicate each type of end-of-line. */
374	extern int eol_mnemonic_unix, eol_mnemonic_dos, eol_mnemonic_mac;
375	/* Mnemonic character to indicate type of end-of-line is not yet decided. */
376	extern int eol_mnemonic_undecided;
377
378	/* Table of coding-systems currently assigned to each coding-category. */
379	extern Lisp_Object coding_category_table[CODING_CATEGORY_IDX_MAX];
380	/* Table of names of symbol for each coding-category. */
381	extern char *coding_category_name[CODING_CATEGORY_IDX_MAX];
382
383	#ifdef emacs
384	extern Lisp_Object Qfile_coding_system;
385	extern Lisp_Object Qcall_process, Qcall_process_region, Qprocess_argument;
386	extern Lisp_Object Qstart_process, Qopen_network_stream;
387
388	/* Coding-system for reading files and receiving data from process. */
389	extern Lisp_Object Vcoding_system_for_read;
390	/* Coding-system for writing files and sending data to process. */
391	extern Lisp_Object Vcoding_system_for_write;
392	/* Coding-system actually used in the latest I/O. */
393	extern Lisp_Object Vlast_coding_system_used;
394
395	/* Coding-system to be used for encoding terminal output. This
396	structure contains information of a coding-system specified by the
397	function `set-terminal-coding-system'. */
398	extern struct coding_system terminal_coding;
399
400	/* Coding-system of what is sent from terminal keyboard. This
401	structure contains information of a coding-system specified by the
402	function `set-keyboard-coding-system'. */
403	extern struct coding_system keyboard_coding;
404
405	extern Lisp_Object Vcoding_system_alist;
406
407	#endif
408
409	#endif /* _CODING_H */