*** empty log message ***
[emacs.git] / src / buffer.h
bloba1d838c037d85173ac70b9099891146061f231a8
1 /* Header file for the buffer manipulation primitives.
2 Copyright (C) 1985, 1986, 1990 Free Software Foundation, Inc.
4 This file is part of GNU Emacs.
6 GNU Emacs is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 1, or (at your option)
9 any later version.
11 GNU Emacs is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU Emacs; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 #ifdef lint
22 #include "undo.h"
23 #endif /* lint */
26 #define SET_PT(position) (current_buffer->text.pt = (position))
28 /* Character position of beginning of buffer. */
29 #define BEG (1)
31 /* Character position of beginning of accessible range of buffer. */
32 #define BEGV (current_buffer->text.begv)
34 /* Character position of point in buffer. The "+ 0" makes this
35 not an l-value, so you can't assign to it. Use SET_PT instead. */
36 #define PT (current_buffer->text.pt + 0)
38 /* Character position of gap in buffer. */
39 #define GPT (current_buffer->text.gpt)
41 /* Character position of end of accessible range of buffer. */
42 #define ZV (current_buffer->text.zv)
44 /* Character position of end of buffer. */
45 #define Z (current_buffer->text.z)
47 /* Modification count. */
48 #define MODIFF (current_buffer->text.modiff)
50 /* Address of beginning of buffer. */
51 #define BEG_ADDR (current_buffer->text.beg)
53 /* Address of beginning of accessible range of buffer. */
54 #define BEGV_ADDR (&FETCH_CHAR (current_buffer->text.begv))
56 /* Address of point in buffer. */
57 #define PT_ADDR (&FETCH_CHAR (current_buffer->text.pt))
59 /* Address of beginning of gap in buffer. */
60 #define GPT_ADDR (current_buffer->text.beg + current_buffer->text.gpt - 1)
62 /* Address of end of gap in buffer. */
63 #define GAP_END_ADDR (current_buffer->text.beg + current_buffer->text.gpt + current_buffer->text.gap_size - 1)
65 /* Address of end of accessible range of buffer. */
66 #define ZV_ADDR (&FETCH_CHAR (current_buffer->text.zv))
68 /* Size of gap. */
69 #define GAP_SIZE (current_buffer->text.gap_size)
71 /* Now similar macros for a specified buffer.
72 Note that many of these evaluate the buffer argument more than once. */
74 /* Character position of beginning of buffer. */
75 #define BUF_BEG(buf) (1)
77 /* Character position of beginning of accessible range of buffer. */
78 #define BUF_BEGV(buf) ((buf)->text.begv)
80 /* Character position of point in buffer. */
81 #define BUF_PT(buf) ((buf)->text.pt)
83 /* Character position of gap in buffer. */
84 #define BUF_GPT(buf) ((buf)->text.gpt)
86 /* Character position of end of accessible range of buffer. */
87 #define BUF_ZV(buf) ((buf)->text.zv)
89 /* Character position of end of buffer. */
90 #define BUF_Z(buf) ((buf)->text.z)
92 /* Modification count. */
93 #define BUF_MODIFF(buf) ((buf)->text.modiff)
95 /* Address of beginning of buffer. */
96 #define BUF_BEG_ADDR(buf) ((buf)->text.beg)
98 /* Macro for setting the value of BUF_ZV (BUF) to VALUE,
99 by varying the end of the accessible region. */
100 #define SET_BUF_ZV(buf, value) ((buf)->text.zv = (value))
101 #define SET_BUF_PT(buf, value) ((buf)->text.pt = (value))
103 /* Size of gap. */
104 #define BUF_GAP_SIZE(buf) ((buf)->text.gap_size)
106 /* Return the address of character at position POS in buffer BUF.
107 Note that both arguments can be computed more than once. */
108 #define BUF_CHAR_ADDRESS(buf, pos) \
109 ((buf)->text.beg + (pos) - 1 \
110 + ((pos) >= (buf)->text.gpt ? (buf)->text.gap_size : 0))
112 /* Convert the address of a char in the buffer into a character position. */
113 #define PTR_CHAR_POS(ptr) \
114 ((ptr) - (current_buffer)->text.beg \
115 - (ptr - (current_buffer)->text.beg < (unsigned) GPT ? 0 : GAP_SIZE) \
116 + 1)
118 struct buffer_text
120 unsigned char *beg; /* Actual address of buffer contents. */
121 int begv; /* Index of beginning of accessible range. */
122 int pt; /* Position of point in buffer. */
123 int gpt; /* Index of gap in buffer. */
124 int zv; /* Index of end of accessible range. */
125 int z; /* Index of end of buffer. */
126 int gap_size; /* Size of buffer's gap */
127 int modiff; /* This counts buffer-modification events
128 for this buffer. It is incremented for
129 each such event, and never otherwise
130 changed. */
133 struct buffer
135 /* Everything before the `name' slot must be of a non-Lisp_Object type,
136 and every slot after `name' must be a Lisp_Object.
138 Check out mark_buffer (alloc.c) to see why.
141 /* This structure holds the coordinates of the buffer contents. */
142 struct buffer_text text;
143 /* Next buffer, in chain of all buffers including killed buffers.
144 This chain is used only for garbage collection, in order to
145 collect killed buffers properly. */
146 struct buffer *next;
147 /* Flags saying which DEFVAR_PER_BUFFER variables
148 are local to this buffer. */
149 int local_var_flags;
150 /* Value of text.modiff as of when visited file was read or written. */
151 int save_modified;
152 /* Set to the modtime of the visited file when read or written.
153 -1 means visited file was nonexistent.
154 0 means visited file modtime unknown; in no case complain
155 about any mismatch on next save attempt. */
156 int modtime;
157 /* the value of text.modiff at the last auto-save. */
158 int auto_save_modified;
159 /* Position in buffer at which display started
160 the last time this buffer was displayed */
161 int last_window_start;
163 /* This is a special exception -- as this slot should not be
164 marked by gc_sweep, and as it is not lisp-accessible as
165 a local variable -- so we regard it as not really being of type
166 Lisp_Object */
167 /* the markers that refer to this buffer.
168 This is actually a single marker ---
169 successive elements in its marker `chain'
170 are the other markers referring to this
171 buffer */
172 Lisp_Object markers;
175 /* Everything from here down must be a Lisp_Object */
178 /* the name of this buffer */
179 Lisp_Object name;
180 /* Nuked: buffer number, assigned when buffer made Lisp_Object number;*/
181 /* the name of the file associated with this buffer */
182 Lisp_Object filename;
183 /* Dir for expanding relative pathnames */
184 Lisp_Object directory;
185 /* true iff this buffer has been been backed
186 up (if you write to its associated file
187 and it hasn't been backed up, then a
188 backup will be made) */
189 /* This isn't really used by the C code, so could be deleted. */
190 Lisp_Object backed_up;
191 /* Length of file when last read or saved. */
192 Lisp_Object save_length;
193 /* file name used for auto-saving this buffer */
194 Lisp_Object auto_save_file_name;
195 /* Non-nil if buffer read-only */
196 Lisp_Object read_only;
197 /* "The mark"; no longer allowed to be nil */
198 Lisp_Object mark;
200 /* Alist of elements (SYMBOL . VALUE-IN-THIS-BUFFER)
201 for all per-buffer variables of this buffer. */
202 Lisp_Object local_var_alist;
205 /* Symbol naming major mode (eg lisp-mode) */
206 Lisp_Object major_mode;
207 /* Pretty name of major mode (eg "Lisp") */
208 Lisp_Object mode_name;
209 /* Format string for mode line */
210 Lisp_Object mode_line_format;
212 /* Keys that are bound local to this buffer */
213 Lisp_Object keymap;
214 /* This buffer's local abbrev table */
215 Lisp_Object abbrev_table;
216 /* This buffer's syntax table. */
217 Lisp_Object syntax_table;
219 /* Values of several buffer-local variables */
220 /* tab-width is buffer-local so that redisplay can find it
221 in buffers that are not current */
222 Lisp_Object case_fold_search;
223 Lisp_Object tab_width;
224 Lisp_Object fill_column;
225 Lisp_Object left_margin;
226 /* Function to call when insert space past fill column */
227 Lisp_Object auto_fill_function;
229 /* String of length 256 mapping each char to its lower-case version. */
230 Lisp_Object downcase_table;
231 /* String of length 256 mapping each char to its upper-case version. */
232 Lisp_Object upcase_table;
234 /* Non-nil means do not display continuation lines */
235 Lisp_Object truncate_lines;
236 /* Non-nil means display ctl chars with uparrow */
237 Lisp_Object ctl_arrow;
238 /* Non-nil means do selective display;
239 See doc string in syms_of_buffer (buffer.c) for details. */
240 Lisp_Object selective_display;
241 #ifndef old
242 /* Non-nil means show ... at end of line followed by invisible lines. */
243 Lisp_Object selective_display_ellipses;
244 #endif
245 /* Alist of (FUNCTION . STRING) for each minor mode enabled in buffer. */
246 Lisp_Object minor_modes;
247 /* t if "self-insertion" should overwrite */
248 Lisp_Object overwrite_mode;
249 /* non-nil means abbrev mode is on. Expand abbrevs automatically. */
250 Lisp_Object abbrev_mode;
251 /* Display table to use for text in this buffer. */
252 Lisp_Object display_table;
253 /* Translate table for case-folding search. */
254 Lisp_Object case_canon_table;
255 /* Inverse translate (equivalence class) table for case-folding search. */
256 Lisp_Object case_eqv_table;
257 /* Changes in the buffer are recorded here for undo.
258 t means don't record anything. */
259 Lisp_Object undo_list;
261 /* List of fields in this buffer. */
262 Lisp_Object fieldlist;
265 extern struct buffer *current_buffer;
267 /* This structure holds the default values of the buffer-local variables
268 defined with DefBufferLispVar, that have special slots in each buffer.
269 The default value occupies the same slot in this structure
270 as an individual buffer's value occupies in that buffer.
271 Setting the default value also goes through the alist of buffers
272 and stores into each buffer that does not say it has a local value. */
274 extern struct buffer buffer_defaults;
276 /* This structure marks which slots in a buffer have corresponding
277 default values in buffer_defaults.
278 Each such slot has a nonzero value in this structure.
279 The value has only one nonzero bit.
281 When a buffer has its own local value for a slot,
282 the bit for that slot (found in the same slot in this structure)
283 is turned on in the buffer's local_var_flags slot.
285 If a slot in this structure is zero, then even though there may
286 be a DefBufferLispVar for the slot, there is no default valuefeor it;
287 and the corresponding slot in buffer_defaults is not used. */
289 extern struct buffer buffer_local_flags;
291 /* For each buffer slot, this points to the Lisp symbol name
292 for that slot in the current buffer. It is 0 for slots
293 that don't have such names. */
295 extern struct buffer buffer_local_symbols;
297 /* Point in the current buffer. */
299 #define point (current_buffer->text.pt + 0)
301 /* Return character at position n. No range checking */
302 #define FETCH_CHAR(n) *(((n)>= GPT ? GAP_SIZE : 0) + (n) + BEG_ADDR - 1)
304 /* BUFFER_CEILING_OF (resp. BUFFER_FLOOR_OF), when applied to n, return
305 the max (resp. min) p such that
307 &FETCH_CHAR (p) - &FETCH_CHAR (n) == p - n */
309 #define BUFFER_CEILING_OF(n) (((n) < GPT && GPT < ZV ? GPT : ZV) - 1)
310 #define BUFFER_FLOOR_OF(n) (BEGV <= GPT && GPT <= (n) ? GPT : BEGV)
312 extern void reset_buffer ();
314 /* Functions to call before and after each text change. */
315 extern Lisp_Object Vbefore_change_function;
316 extern Lisp_Object Vafter_change_function;
317 extern Lisp_Object Vfirst_change_function;
319 /* Fields.
321 A field is like a marker but it defines a region rather than a
322 point. Like a marker, a field is asocated with a buffer.
323 The field mechanism uses the marker mechanism in the
324 sense that its start and end points are maintained as markers
325 updated in the usual way as the buffer changes.
327 A field can be protected or unprotected. If it is protected,
328 no modifications can be made that affect the field in its buffer,
329 when protected field checking is enabled.
331 Each field also contains an alist, in which you can store
332 whatever you like. */
334 /* Slots in a field: */
336 #define FIELD_BUFFER(f) (XVECTOR(f)->contents[1])
337 #define FIELD_START_MARKER(f) (XVECTOR(f)->contents[2])
338 #define FIELD_END_MARKER(f) (XVECTOR(f)->contents[3])
339 #define FIELD_PROTECTED_FLAG(f) (XVECTOR(f)->contents[4])
340 #define FIELD_ALIST(f) (XVECTOR(f)->contents[5])
342 /* Allocation of buffer data. */
343 #ifdef REL_ALLOC
344 #define BUFFER_ALLOC(data,size) ((unsigned char *) r_alloc (&data, (size)))
345 #define BUFFER_REALLOC(data,size) ((unsigned char *) r_re_alloc (&data, (size)))
346 #define BUFFER_FREE(data) (r_alloc_free (&data))
347 #define R_ALLOC_DECLARE(var,data) (r_alloc_declare (&var, (data)))
348 #else
349 #define BUFFER_ALLOC(data,size) (data = (unsigned char *) malloc ((size)))
350 #define BUFFER_REALLOC(data,size) ((unsigned char *) realloc ((data), (size)))
351 #define BUFFER_FREE(data) (free ((data)))
352 #define R_ALLOC_DECLARE(var,data)
353 #endif
355 /* A search buffer, with a fastmap allocated and ready to go. */
356 extern struct re_pattern_buffer searchbuf;