1 /* Header file for the buffer manipulation primitives.
2 Copyright (C) 1985, 86, 93, 94, 95, 97, 1998 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 2, or (at your option)
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, Inc., 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* Accessing the parameters of the current buffer. */
24 /* These macros come in pairs, one for the char position
25 and one for the byte position. */
27 /* Position of beginning of buffer. */
31 /* Position of beginning of accessible range of buffer. */
32 #define BEGV (current_buffer->begv)
33 #define BEGV_BYTE (current_buffer->begv_byte)
35 /* Position of point in buffer. The "+ 0" makes this
36 not an l-value, so you can't assign to it. Use SET_PT instead. */
37 #define PT (current_buffer->pt + 0)
38 #define PT_BYTE (current_buffer->pt_byte + 0)
40 /* Position of gap in buffer. */
41 #define GPT (current_buffer->text->gpt)
42 #define GPT_BYTE (current_buffer->text->gpt_byte)
44 /* Position of end of accessible range of buffer. */
45 #define ZV (current_buffer->zv)
46 #define ZV_BYTE (current_buffer->zv_byte)
48 /* Position of end of buffer. */
49 #define Z (current_buffer->text->z)
50 #define Z_BYTE (current_buffer->text->z_byte)
52 /* Macros for the addresses of places in the buffer. */
54 /* Address of beginning of buffer. */
55 #define BEG_ADDR (current_buffer->text->beg)
57 /* Address of beginning of accessible range of buffer. */
58 #define BEGV_ADDR (BYTE_POS_ADDR (current_buffer->begv_byte))
60 /* Address of point in buffer. */
61 #define PT_ADDR (BYTE_POS_ADDR (current_buffer->pt_byte))
63 /* Address of beginning of gap in buffer. */
64 #define GPT_ADDR (current_buffer->text->beg + current_buffer->text->gpt_byte - 1)
66 /* Address of end of gap in buffer. */
67 #define GAP_END_ADDR (current_buffer->text->beg + current_buffer->text->gpt_byte + current_buffer->text->gap_size - 1)
69 /* Address of end of accessible range of buffer. */
70 #define ZV_ADDR (BYTE_POS_ADDR (current_buffer->zv_byte))
72 /* Address of end of buffer. */
73 #define Z_ADDR (current_buffer->text->beg + current_buffer->text->gap_size + current_buffer->text->z_byte - 1)
76 #define GAP_SIZE (current_buffer->text->gap_size)
78 /* Is the current buffer narrowed? */
79 #define NARROWED ((BEGV != BEG) || (ZV != Z))
81 /* Modification count. */
82 #define MODIFF (current_buffer->text->modiff)
84 /* Overlay modification count. */
85 #define OVERLAY_MODIFF (current_buffer->text->overlay_modiff)
87 /* Modification count as of last visit or save. */
88 #define SAVE_MODIFF (current_buffer->text->save_modiff)
90 /* BUFFER_CEILING_OF (resp. BUFFER_FLOOR_OF), when applied to n, return
91 the max (resp. min) p such that
93 BYTE_POS_ADDR (p) - BYTE_POS_ADDR (n) == p - n */
95 #define BUFFER_CEILING_OF(BYTEPOS) \
96 (((BYTEPOS) < GPT_BYTE && GPT < ZV ? GPT_BYTE : ZV_BYTE) - 1)
97 #define BUFFER_FLOOR_OF(BYTEPOS) \
98 (BEGV <= GPT && GPT_BYTE <= (BYTEPOS) ? GPT_BYTE : BEGV_BYTE)
100 /* Similar macros to operate on a specified buffer.
101 Note that many of these evaluate the buffer argument more than once. */
103 /* Position of beginning of buffer. */
104 #define BUF_BEG(buf) (1)
105 #define BUF_BEG_BYTE(buf) (1)
107 /* Position of beginning of accessible range of buffer. */
108 #define BUF_BEGV(buf) ((buf)->begv)
109 #define BUF_BEGV_BYTE(buf) ((buf)->begv_byte)
111 /* Position of point in buffer. */
112 #define BUF_PT(buf) ((buf)->pt)
113 #define BUF_PT_BYTE(buf) ((buf)->pt_byte)
115 /* Position of gap in buffer. */
116 #define BUF_GPT(buf) ((buf)->text->gpt)
117 #define BUF_GPT_BYTE(buf) ((buf)->text->gpt_byte)
119 /* Position of end of accessible range of buffer. */
120 #define BUF_ZV(buf) ((buf)->zv)
121 #define BUF_ZV_BYTE(buf) ((buf)->zv_byte)
123 /* Position of end of buffer. */
124 #define BUF_Z(buf) ((buf)->text->z)
125 #define BUF_Z_BYTE(buf) ((buf)->text->z_byte)
127 /* Address of beginning of buffer. */
128 #define BUF_BEG_ADDR(buf) ((buf)->text->beg)
130 /* Address of beginning of gap of buffer. */
131 #define BUF_GPT_ADDR(buf) ((buf)->text->beg + (buf)->text->gpt_byte - 1)
133 /* Address of end of buffer. */
134 #define BUF_Z_ADDR(buf) ((buf)->text->beg + (buf)->text->gap_size + (buf)->text->z_byte - 1)
136 /* Address of end of gap in buffer. */
137 #define BUF_GAP_END_ADDR(buf) ((buf)->text->beg + (buf)->text->gpt_byte + (buf)->text->gap_size - 1)
140 #define BUF_GAP_SIZE(buf) ((buf)->text->gap_size)
142 /* Is this buffer narrowed? */
143 #define BUF_NARROWED(buf) ((BUF_BEGV (buf) != BUF_BEG (buf)) \
144 || (BUF_ZV (buf) != BUF_Z (buf)))
146 /* Modification count. */
147 #define BUF_MODIFF(buf) ((buf)->text->modiff)
149 /* Modification count as of last visit or save. */
150 #define BUF_SAVE_MODIFF(buf) ((buf)->text->save_modiff)
152 /* Overlay modification count. */
153 #define BUF_OVERLAY_MODIFF(buf) ((buf)->text->overlay_modiff)
155 /* Interval tree of buffer. */
156 #define BUF_INTERVALS(buf) ((buf)->text->intervals)
158 /* Marker chain of buffer. */
159 #define BUF_MARKERS(buf) ((buf)->text->markers)
161 /* Macros to set PT in the current buffer, or another buffer.. */
163 #ifdef USE_TEXT_PROPERTIES
164 #define SET_PT(position) (set_point (current_buffer, (position)))
165 #define TEMP_SET_PT(position) (temp_set_point (current_buffer, (position)))
167 #define SET_PT_BOTH(position, byte) \
168 (set_point_both (current_buffer, (position), (byte)))
169 #define TEMP_SET_PT_BOTH(position, byte) \
170 (temp_set_point_both (current_buffer, (position), (byte)))
172 #define BUF_SET_PT(buffer, position) \
173 (set_point ((buffer), (position)))
174 #define BUF_TEMP_SET_PT(buffer, position) \
175 (temp_set_point ((buffer), (position)))
177 extern void set_point
P_ ((struct buffer
*, int));
178 extern INLINE
void temp_set_point
P_ ((struct buffer
*, int));
179 extern void set_point_both
P_ ((struct buffer
*, int, int));
180 extern INLINE
void temp_set_point_both
P_ ((struct buffer
*, int, int));
182 #else /* don't support text properties */
184 #define SET_PT(position) (current_buffer->pt = (position))
185 #define TEMP_SET_PT(position) (current_buffer->pt = (position))
187 #define SET_PT_BOTH(position, byte) \
188 (current_buffer->pt = (position), \
189 current_buffer->pt_byte = (byte))
191 #define TEMP_SET_PT_BOTH(position, byte) \
192 (current_buffer->pt = (position), \
193 current_buffer->pt_byte = (byte))
195 #define BUF_SET_PT(buffer, position) (buffer->pt = (position))
196 #define BUF_TEMP_SET_PT(buffer, position) (buffer->pt = (position))
197 #endif /* don't support text properties */
199 /* Macros for setting the BEGV, ZV or PT of a given buffer.
201 SET_BUF_PT* seet to be redundant. Get rid of them?
203 The ..._BOTH macros take both a charpos and a bytepos,
204 which must correspond to each other.
206 The macros without ..._BOTH take just a charpos,
207 and compute the bytepos from it. */
209 #define SET_BUF_BEGV(buf, charpos) \
210 ((buf)->begv_byte = buf_charpos_to_bytepos ((buf), (charpos)), \
211 (buf)->begv = (charpos))
213 #define SET_BUF_ZV(buf, charpos) \
214 ((buf)->zv_byte = buf_charpos_to_bytepos ((buf), (charpos)), \
215 (buf)->zv = (charpos))
217 #define SET_BUF_BEGV_BOTH(buf, charpos, byte) \
218 ((buf)->begv = (charpos), \
219 (buf)->begv_byte = (byte))
221 #define SET_BUF_ZV_BOTH(buf, charpos, byte) \
222 ((buf)->zv = (charpos), \
223 (buf)->zv_byte = (byte))
225 #define SET_BUF_PT_BOTH(buf, charpos, byte) \
226 ((buf)->pt = (charpos), \
227 (buf)->pt_byte = (byte))
229 /* Macros to access a character or byte in the current buffer,
230 or convert between a byte position and an address.
231 These macros do not check that the position is in range. */
233 /* Access a Lisp position value in POS,
234 and store the charpos in CHARPOS and the bypepos in BYPEPOS. */
236 #define DECODE_POSITION(charpos, bytepos, pos) \
239 Lisp_Object __pos = (pos); \
240 if (NUMBERP (__pos)) \
243 bytepos = buf_charpos_to_bytepos (current_buffer, __pos); \
245 else if (MARKERP (__pos)) \
247 charpos = marker_position (__pos); \
248 bytepos = marker_byte_position (__pos); \
251 wrong_type_argument (Qinteger_or_marker_p, __pos); \
255 /* Return the address of byte position N in current buffer. */
257 #define BYTE_POS_ADDR(n) \
258 (((n) >= GPT_BYTE ? GAP_SIZE : 0) + (n) + BEG_ADDR - 1)
260 /* Return the address of char position N. */
262 #define CHAR_POS_ADDR(n) \
263 (((n) >= GPT ? GAP_SIZE : 0) \
264 + buf_charpos_to_bytepos (current_buffer, n) \
267 /* Convert a character position to a byte position. */
269 #define CHAR_TO_BYTE(charpos) \
270 (buf_charpos_to_bytepos (current_buffer, charpos))
272 /* Convert a byte position to a character position. */
274 #define BYTE_TO_CHAR(bytepos) \
275 (buf_bytepos_to_charpos (current_buffer, bytepos))
277 /* Convert PTR, the address of a byte in the buffer, into a byte position. */
279 #define PTR_BYTE_POS(ptr) \
280 ((ptr) - (current_buffer)->text->beg \
281 - (ptr - (current_buffer)->text->beg < (unsigned) GPT_BYTE ? 0 : GAP_SIZE) \
284 /* Return character at position POS. */
286 #define FETCH_CHAR(pos) \
287 (!NILP (current_buffer->enable_multibyte_characters) \
288 ? FETCH_MULTIBYTE_CHAR ((pos)) \
289 : FETCH_BYTE ((pos)))
291 /* Return the byte at byte position N. */
293 #define FETCH_BYTE(n) *(BYTE_POS_ADDR ((n)))
295 /* Variables used locally in FETCH_MULTIBYTE_CHAR. */
296 extern unsigned char *_fetch_multibyte_char_p
;
297 extern int _fetch_multibyte_char_len
;
299 /* Return character code of multi-byte form at position POS. If POS
300 doesn't point the head of valid multi-byte form, only the byte at
301 POS is returned. No range checking. */
303 #define FETCH_MULTIBYTE_CHAR(pos) \
304 (_fetch_multibyte_char_p = (((pos) >= GPT_BYTE ? GAP_SIZE : 0) \
305 + (pos) + BEG_ADDR - 1), \
306 _fetch_multibyte_char_len \
307 = ((pos) >= GPT_BYTE ? ZV_BYTE : GPT_BYTE) - (pos), \
308 STRING_CHAR (_fetch_multibyte_char_p, _fetch_multibyte_char_len))
310 /* Macros for accessing a character or byte,
311 or converting between byte positions and addresses,
312 in a specified buffer. */
314 /* Return the address of character at byte position POS in buffer BUF.
315 Note that both arguments can be computed more than once. */
317 #define BUF_BYTE_ADDRESS(buf, pos) \
318 ((buf)->text->beg + (pos) - 1 \
319 + ((pos) >= (buf)->text->gpt_byte ? (buf)->text->gap_size : 0))
321 /* Return the address of character at char position POS in buffer BUF.
322 Note that both arguments can be computed more than once. */
324 #define BUF_CHAR_ADDRESS(buf, pos) \
325 ((buf)->text->beg + buf_charpos_to_bytepos ((buf), (pos)) - 1 \
326 + ((pos) >= (buf)->text->gpt ? (buf)->text->gap_size : 0))
328 /* Convert PTR, the address of a char in buffer BUF,
329 into a character position. */
331 #define BUF_PTR_BYTE_POS(buf, ptr) \
332 ((ptr) - (buf)->text->beg \
333 - (ptr - (buf)->text->beg < (unsigned) BUF_GPT_BYTE ((buf)) \
334 ? 0 : BUF_GAP_SIZE ((buf))) \
337 /* Return the character at byte position POS in buffer BUF. */
339 #define BUF_FETCH_CHAR(buf, pos) \
340 (!NILP (buf->enable_multibyte_characters) \
341 ? BUF_FETCH_MULTIBYTE_CHAR ((buf), (pos)) \
342 : BUF_FETCH_BYTE ((buf), (pos)))
344 /* Return the byte at byte position N in buffer BUF. */
346 #define BUF_FETCH_BYTE(buf, n) \
347 *(BUF_BYTE_ADDRESS ((buf), (n)))
349 /* Return character code of multi-byte form at byte position POS in BUF.
350 If POS doesn't point the head of valid multi-byte form, only the byte at
351 POS is returned. No range checking. */
353 #define BUF_FETCH_MULTIBYTE_CHAR(buf, pos) \
354 (_fetch_multibyte_char_p \
355 = (((pos) >= BUF_GPT_BYTE (buf) ? BUF_GAP_SIZE (buf) : 0) \
356 + (pos) + BUF_BEG_ADDR (buf) - 1), \
357 _fetch_multibyte_char_len \
358 = (((pos) >= BUF_GPT_BYTE (buf) ? BUF_ZV_BYTE (buf) : BUF_GPT_BYTE (buf)) \
360 STRING_CHAR (_fetch_multibyte_char_p, _fetch_multibyte_char_len))
362 /* Define the actual buffer data structures. */
364 /* This data structure describes the actual text contents of a buffer.
365 It is shared between indirect buffers and their base buffer. */
369 unsigned char *beg
; /* Actual address of buffer contents. */
370 int gpt
; /* Char pos of gap in buffer. */
371 int z
; /* Char pos of end of buffer. */
372 int gpt_byte
; /* Byte pos of gap in buffer. */
373 int z_byte
; /* Byte pos of end of buffer. */
374 int gap_size
; /* Size of buffer's gap. */
375 int modiff
; /* This counts buffer-modification events
376 for this buffer. It is incremented for
377 each such event, and never otherwise
379 int save_modiff
; /* Previous value of modiff, as of last
380 time buffer visited or saved a file. */
382 int overlay_modiff
; /* Counts modifications to overlays. */
384 /* Properties of this buffer's text -- conditionally compiled. */
387 /* The markers that refer to this buffer.
388 This is actually a single marker ---
389 successive elements in its marker `chain'
390 are the other markers referring to this buffer. */
394 /* This is the structure that the buffer Lisp object points to. */
398 /* Everything before the `name' slot must be of a non-Lisp_Object type,
399 and every slot after `name' must be a Lisp_Object.
401 Check out mark_buffer (alloc.c) to see why. */
405 /* Next buffer, in chain of all buffers including killed buffers.
406 This chain is used only for garbage collection, in order to
407 collect killed buffers properly.
408 Note that vectors and most pseudovectors are all on one chain,
409 but buffers are on a separate chain of their own. */
412 /* This structure holds the coordinates of the buffer contents
413 in ordinary buffers. In indirect buffers, this is not used. */
414 struct buffer_text own_text
;
416 /* This points to the `struct buffer_text' that used for this buffer.
417 In an ordinary buffer, this is the own_text field above.
418 In an indirect buffer, this is the own_text field of another buffer. */
419 struct buffer_text
*text
;
421 /* Char position of point in buffer. */
423 /* Byte position of point in buffer. */
425 /* Char position of beginning of accessible range. */
427 /* Byte position of beginning of accessible range. */
429 /* Char position of end of accessible range. */
431 /* Byte position of end of accessible range. */
434 /* In an indirect buffer, this points to the base buffer.
435 In an ordinary buffer, it is 0. */
436 struct buffer
*base_buffer
;
438 /* Flags saying which DEFVAR_PER_BUFFER variables
439 are local to this buffer. */
441 /* Set to the modtime of the visited file when read or written.
442 -1 means visited file was nonexistent.
443 0 means visited file modtime unknown; in no case complain
444 about any mismatch on next save attempt. */
446 /* the value of text->modiff at the last auto-save. */
447 int auto_save_modified
;
448 /* The time at which we detected a failure to auto-save,
449 Or -1 if we didn't have a failure. */
450 int auto_save_failure_time
;
451 /* Position in buffer at which display started
452 the last time this buffer was displayed. */
453 int last_window_start
;
455 /* Set nonzero whenever the narrowing is changed in this buffer. */
458 /* If the long line scan cache is enabled (i.e. the buffer-local
459 variable cache-long-line-scans is non-nil), newline_cache
460 points to the newline cache, and width_run_cache points to the
463 The newline cache records which stretches of the buffer are
464 known *not* to contain newlines, so that they can be skipped
465 quickly when we search for newlines.
467 The width run cache records which stretches of the buffer are
468 known to contain characters whose widths are all the same. If
469 the width run cache maps a character to a value > 0, that value is
470 the character's width; if it maps a character to zero, we don't
471 know what its width is. This allows compute_motion to process
472 such regions very quickly, using algebra instead of inspecting
473 each character. See also width_table, below. */
474 struct region_cache
*newline_cache
;
475 struct region_cache
*width_run_cache
;
477 /* Everything from here down must be a Lisp_Object */
480 /* The name of this buffer. */
482 /* The name of the file visited in this buffer, or nil. */
483 Lisp_Object filename
;
484 /* Dir for expanding relative file names. */
485 Lisp_Object directory
;
486 /* True iff this buffer has been backed up (if you write to the
487 visited file and it hasn't been backed up, then a backup will
489 /* This isn't really used by the C code, so could be deleted. */
490 Lisp_Object backed_up
;
491 /* Length of file when last read or saved.
492 This is not in the struct buffer_text
493 because it's not used in indirect buffers at all. */
494 Lisp_Object save_length
;
495 /* File name used for auto-saving this buffer.
496 This is not in the struct buffer_text
497 because it's not used in indirect buffers at all. */
498 Lisp_Object auto_save_file_name
;
500 /* Non-nil if buffer read-only. */
501 Lisp_Object read_only
;
502 /* "The mark". This is a marker which may
503 point into this buffer or may point nowhere. */
506 /* Alist of elements (SYMBOL . VALUE-IN-THIS-BUFFER)
507 for all per-buffer variables of this buffer. */
508 Lisp_Object local_var_alist
;
510 /* Symbol naming major mode (eg, lisp-mode). */
511 Lisp_Object major_mode
;
512 /* Pretty name of major mode (eg, "Lisp"). */
513 Lisp_Object mode_name
;
514 /* Mode line element that controls format of mode line. */
515 Lisp_Object mode_line_format
;
517 /* Keys that are bound local to this buffer. */
519 /* This buffer's local abbrev table. */
520 Lisp_Object abbrev_table
;
521 /* This buffer's syntax table. */
522 Lisp_Object syntax_table
;
523 /* This buffer's category table. */
524 Lisp_Object category_table
;
526 /* Values of several buffer-local variables */
527 /* tab-width is buffer-local so that redisplay can find it
528 in buffers that are not current */
529 Lisp_Object case_fold_search
;
530 Lisp_Object tab_width
;
531 Lisp_Object fill_column
;
532 Lisp_Object left_margin
;
533 /* Function to call when insert space past fill column. */
534 Lisp_Object auto_fill_function
;
535 /* nil: text, t: binary.
536 This value is meaningful only on certain operating systems. */
537 /* Actually, we don't need this flag any more because end-of-line
538 is handled correctly according to the buffer-file-coding-system
539 of the buffer. Just keeping it for backward compatibility. */
540 Lisp_Object buffer_file_type
;
542 /* Case table for case-conversion in this buffer.
543 This char-table maps each char into its lower-case version. */
544 Lisp_Object downcase_table
;
545 /* Char-table mapping each char to its upper-case version. */
546 Lisp_Object upcase_table
;
547 /* Char-table for conversion for case-folding search. */
548 Lisp_Object case_canon_table
;
549 /* Char-table of equivalences for case-folding search. */
550 Lisp_Object case_eqv_table
;
552 /* Non-nil means do not display continuation lines. */
553 Lisp_Object truncate_lines
;
554 /* Non-nil means display ctl chars with uparrow. */
555 Lisp_Object ctl_arrow
;
556 /* Non-nil means display text from right to left. */
557 Lisp_Object direction_reversed
;
558 /* Non-nil means do selective display;
559 see doc string in syms_of_buffer (buffer.c) for details. */
560 Lisp_Object selective_display
;
562 /* Non-nil means show ... at end of line followed by invisible lines. */
563 Lisp_Object selective_display_ellipses
;
565 /* Alist of (FUNCTION . STRING) for each minor mode enabled in buffer. */
566 Lisp_Object minor_modes
;
567 /* t if "self-insertion" should overwrite; `binary' if it should also
568 overwrite newlines and tabs - for editing executables and the like. */
569 Lisp_Object overwrite_mode
;
570 /* non-nil means abbrev mode is on. Expand abbrevs automatically. */
571 Lisp_Object abbrev_mode
;
572 /* Display table to use for text in this buffer. */
573 Lisp_Object display_table
;
574 /* t means the mark and region are currently active. */
575 Lisp_Object mark_active
;
577 /* Changes in the buffer are recorded here for undo.
578 t means don't record anything.
579 This information belongs to the base buffer of an indirect buffer,
580 But we can't store it in the struct buffer_text
581 because local variables have to be right in the struct buffer.
582 So we copy it around in set_buffer_internal. */
583 Lisp_Object undo_list
;
585 /* List of overlays that end at or before the current center,
586 in order of end-position. */
587 Lisp_Object overlays_before
;
589 /* List of overlays that end after the current center,
590 in order of start-position. */
591 Lisp_Object overlays_after
;
593 /* Position where the overlay lists are centered. */
594 Lisp_Object overlay_center
;
596 /* Non-nil means the buffer contents are regarded as multi-byte
597 form of characters, not a binary code. */
598 Lisp_Object enable_multibyte_characters
;
600 /* Coding system to be used for encoding the buffer contents on
602 Lisp_Object buffer_file_coding_system
;
604 /* List of symbols naming the file format used for visited file. */
605 Lisp_Object file_format
;
607 /* True if the newline position cache and width run cache are
608 enabled. See search.c and indent.c. */
609 Lisp_Object cache_long_line_scans
;
611 /* If the width run cache is enabled, this table contains the
612 character widths width_run_cache (see above) assumes. When we
613 do a thorough redisplay, we compare this against the buffer's
614 current display table to see whether the display table has
615 affected the widths of any characters. If it has, we
616 invalidate the width run cache, and re-initialize width_table. */
617 Lisp_Object width_table
;
619 /* In an indirect buffer, or a buffer that is the base of an
620 indirect buffer, this holds a marker that records
621 PT for this buffer when the buffer is not current. */
622 Lisp_Object pt_marker
;
624 /* In an indirect buffer, or a buffer that is the base of an
625 indirect buffer, this holds a marker that records
626 BEGV for this buffer when the buffer is not current. */
627 Lisp_Object begv_marker
;
629 /* In an indirect buffer, or a buffer that is the base of an
630 indirect buffer, this holds a marker that records
631 ZV for this buffer when the buffer is not current. */
632 Lisp_Object zv_marker
;
634 /* This holds the point value before the last scroll operation.
635 Explicitly setting point sets this to nil. */
636 Lisp_Object point_before_scroll
;
638 /* Truename of the visited file, or nil. */
639 Lisp_Object file_truename
;
641 /* Invisibility spec of this buffer.
642 t => any non-nil `invisible' property means invisible.
643 A list => `invisible' property means invisible
644 if it is memq in that list. */
645 Lisp_Object invisibility_spec
;
647 /* This is the last window that was selected with this buffer in it,
648 or nil if that window no longer displays this buffer. */
649 Lisp_Object last_selected_window
;
651 /* Incremented each time the buffer is displayed in a window. */
652 Lisp_Object display_count
;
654 /* These are so we don't have to recompile everything
655 the next few times we add a new slot. */
656 Lisp_Object extra2
, extra3
;
659 /* This points to the current buffer. */
661 extern struct buffer
*current_buffer
;
663 /* This structure holds the default values of the buffer-local variables
664 that have special slots in each buffer.
665 The default value occupies the same slot in this structure
666 as an individual buffer's value occupies in that buffer.
667 Setting the default value also goes through the alist of buffers
668 and stores into each buffer that does not say it has a local value. */
670 extern struct buffer buffer_defaults
;
672 /* This structure marks which slots in a buffer have corresponding
673 default values in buffer_defaults.
674 Each such slot has a nonzero value in this structure.
675 The value has only one nonzero bit.
677 When a buffer has its own local value for a slot,
678 the bit for that slot (found in the same slot in this structure)
679 is turned on in the buffer's local_var_flags slot.
681 If a slot in this structure is zero, then even though there may
682 be a Lisp-level local variable for the slot, it has no default value,
683 and the corresponding slot in buffer_defaults is not used. */
685 extern struct buffer buffer_local_flags
;
687 /* For each buffer slot, this points to the Lisp symbol name
688 for that slot in the current buffer. It is 0 for slots
689 that don't have such names. */
691 extern struct buffer buffer_local_symbols
;
693 /* This structure holds the required types for the values in the
694 buffer-local slots. If a slot contains Qnil, then the
695 corresponding buffer slot may contain a value of any type. If a
696 slot contains an integer, then prospective values' tags must be
697 equal to that integer (except nil is always allowed).
698 When a tag does not match, the function
699 buffer_slot_type_mismatch will signal an error.
701 If a slot here contains -1, the corresponding variable is read-only. */
703 extern struct buffer buffer_local_types
;
705 extern void reset_buffer
P_ ((struct buffer
*));
706 extern void evaporate_overlays
P_ ((int));
707 extern int overlays_at
P_ ((int, int, Lisp_Object
**, int *, int *, int *));
708 extern int sort_overlays
P_ ((Lisp_Object
*, int, struct window
*));
709 extern void recenter_overlay_lists
P_ ((struct buffer
*, int));
710 extern int overlay_strings
P_ ((int, struct window
*, unsigned char **));
711 extern void validate_region
P_ ((Lisp_Object
*, Lisp_Object
*));
712 extern void set_buffer_internal
P_ ((struct buffer
*));
713 extern void set_buffer_internal_1
P_ ((struct buffer
*));
714 extern void set_buffer_temp
P_ ((struct buffer
*));
715 extern void record_buffer
P_ ((Lisp_Object
));
716 extern void buffer_slot_type_mismatch
P_ ((int));
717 extern void fix_overlays_before
P_ ((struct buffer
*, int, int));
720 EXFUN (Fbuffer_name
, 1);
721 EXFUN (Fget_file_buffer
, 1);
722 EXFUN (Fnext_overlay_change
, 1);
723 EXFUN (Fdelete_overlay
, 1);
725 /* Functions to call before and after each text change. */
726 extern Lisp_Object Vbefore_change_function
;
727 extern Lisp_Object Vafter_change_function
;
728 extern Lisp_Object Vbefore_change_functions
;
729 extern Lisp_Object Vafter_change_functions
;
730 extern Lisp_Object Vfirst_change_hook
;
731 extern Lisp_Object Qbefore_change_functions
;
732 extern Lisp_Object Qafter_change_functions
;
733 extern Lisp_Object Qfirst_change_hook
;
735 extern Lisp_Object Vdeactivate_mark
;
736 extern Lisp_Object Vtransient_mark_mode
;
740 /* 1 if the OV is an overlay object. */
741 #define OVERLAY_VALID(OV) (OVERLAYP (OV))
743 /* Return the marker that stands for where OV starts in the buffer. */
744 #define OVERLAY_START(OV) (XOVERLAY (OV)->start)
746 /* Return the marker that stands for where OV ends in the buffer. */
747 #define OVERLAY_END(OV) (XOVERLAY (OV)->end)
749 /* Return the actual buffer position for the marker P.
750 We assume you know which buffer it's pointing into. */
752 #define OVERLAY_POSITION(P) \
753 (GC_MARKERP (P) ? marker_position (P) : (abort (), 0))
755 /* Allocation of buffer text. */
758 #define BUFFER_ALLOC(data,size) ((unsigned char *) r_alloc (&data, (size)))
759 #define BUFFER_REALLOC(data,size) ((unsigned char *) r_re_alloc (&data, (size)))
760 #define BUFFER_FREE(data) (r_alloc_free (&data))
761 #define R_ALLOC_DECLARE(var,data) (r_alloc_declare (&var, (data)))
763 #define BUFFER_ALLOC(data,size) (data = (unsigned char *) malloc ((size)))
764 #define BUFFER_REALLOC(data,size) ((unsigned char *) realloc ((data), (size)))
765 #define BUFFER_FREE(data) (free ((data)))
766 #define R_ALLOC_DECLARE(var,data)