buffer.c 151 KB
Newer Older
Roland McGrath's avatar
Roland McGrath committed
1
/* Buffer manipulation primitives for GNU Emacs.
2
   Copyright (C) 1985,86,87,88,89,93,94,95,97,98, 1999
3
	Free Software Foundation, Inc.
Roland McGrath's avatar
Roland McGrath committed
4 5 6 7 8

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
9
the Free Software Foundation; either version 2, or (at your option)
Roland McGrath's avatar
Roland McGrath committed
10 11 12 13 14 15 16 17 18
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
19 20
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */
Roland McGrath's avatar
Roland McGrath committed
21

22
#include <config.h>
Roland McGrath's avatar
Roland McGrath committed
23

24 25
#include <sys/types.h>
#include <sys/stat.h>
Roland McGrath's avatar
Roland McGrath committed
26
#include <sys/param.h>
Richard M. Stallman's avatar
Richard M. Stallman committed
27 28 29
#include <errno.h>

extern int errno;
Roland McGrath's avatar
Roland McGrath committed
30 31 32 33 34 35

#ifndef MAXPATHLEN
/* in 4.1, param.h fails to define this. */
#define MAXPATHLEN 1024
#endif /* not MAXPATHLEN */

Andreas Schwab's avatar
Andreas Schwab committed
36 37 38
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
Roland McGrath's avatar
Roland McGrath committed
39
#include "lisp.h"
40
#include "intervals.h"
Roland McGrath's avatar
Roland McGrath committed
41 42 43
#include "window.h"
#include "commands.h"
#include "buffer.h"
Karl Heuer's avatar
Karl Heuer committed
44
#include "charset.h"
45
#include "region-cache.h"
Roland McGrath's avatar
Roland McGrath committed
46
#include "indent.h"
Richard M. Stallman's avatar
Richard M. Stallman committed
47
#include "blockinput.h"
48
#include "frame.h"
Roland McGrath's avatar
Roland McGrath committed
49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

struct buffer *current_buffer;		/* the current buffer */

/* First buffer in chain of all buffers (in reverse order of creation).
   Threaded through ->next.  */

struct buffer *all_buffers;

/* This structure holds the default values of the buffer-local variables
   defined with DEFVAR_PER_BUFFER, that have special slots in each buffer.
   The default value occupies the same slot in this structure
   as an individual buffer's value occupies in that buffer.
   Setting the default value also goes through the alist of buffers
   and stores into each buffer that does not say it has a local value.  */

struct buffer buffer_defaults;

/* A Lisp_Object pointer to the above, used for staticpro */

static Lisp_Object Vbuffer_defaults;

/* This structure marks which slots in a buffer have corresponding
   default values in buffer_defaults.
   Each such slot has a nonzero value in this structure.
   The value has only one nonzero bit.

   When a buffer has its own local value for a slot,
76 77
   the entry for that slot (found in the same slot in this structure)
   is turned on in the buffer's local_flags array.
Roland McGrath's avatar
Roland McGrath committed
78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101

   If a slot in this structure is -1, then even though there may
   be a DEFVAR_PER_BUFFER for the slot, there is no default value for it;
   and the corresponding slot in buffer_defaults is not used.

   If a slot is -2, then there is no DEFVAR_PER_BUFFER for it,
   but there is a default value which is copied into each buffer.

   If a slot in this structure is negative, then even though there may
   be a DEFVAR_PER_BUFFER for the slot, there is no default value for it;
   and the corresponding slot in buffer_defaults is not used.

   If a slot in this structure corresponding to a DEFVAR_PER_BUFFER is
   zero, that is a bug */

struct buffer buffer_local_flags;

/* This structure holds the names of symbols whose values may be
   buffer-local.  It is indexed and accessed in the same way as the above. */

struct buffer buffer_local_symbols;
/* A Lisp_Object pointer to the above, used for staticpro */
static Lisp_Object Vbuffer_local_symbols;

102 103 104 105
/* This structure holds the required types for the values in the
   buffer-local slots.  If a slot contains Qnil, then the
   corresponding buffer slot may contain a value of any type.  If a
   slot contains an integer, then prospective values' tags must be
106 107 108 109 110
   equal to that integer (except nil is always allowed).
   When a tag does not match, the function
   buffer_slot_type_mismatch will signal an error.

   If a slot here contains -1, the corresponding variable is read-only.  */
111 112
struct buffer buffer_local_types;

113 114
/* Flags indicating which built-in buffer-local variables
   are permanent locals.  */
115
static char buffer_permanent_local_flags[MAX_PER_BUFFER_VARS];
116 117 118

/* Number of per-buffer variables used.  */

119
int last_per_buffer_idx;
120

Roland McGrath's avatar
Roland McGrath committed
121
Lisp_Object Fset_buffer ();
Roland McGrath's avatar
Roland McGrath committed
122
void set_buffer_internal ();
123
void set_buffer_internal_1 ();
124
static void call_overlay_mod_hooks ();
125
static void swap_out_buffer_local_variables ();
126
static void reset_buffer_local_variables ();
Roland McGrath's avatar
Roland McGrath committed
127 128 129 130 131 132 133 134 135

/* Alist of all buffer names vs the buffers. */
/* This used to be a variable, but is no longer,
 to prevent lossage due to user rplac'ing this alist or its elements.  */
Lisp_Object Vbuffer_alist;

/* Functions to call before and after each text change. */
Lisp_Object Vbefore_change_function;
Lisp_Object Vafter_change_function;
136 137
Lisp_Object Vbefore_change_functions;
Lisp_Object Vafter_change_functions;
Roland McGrath's avatar
Roland McGrath committed
138

139 140
Lisp_Object Vtransient_mark_mode;

141 142 143 144 145
/* t means ignore all read-only text properties.
   A list means ignore such a property if its value is a member of the list.
   Any non-nil value means ignore buffer-read-only.  */
Lisp_Object Vinhibit_read_only;

146 147 148 149
/* List of functions to call that can query about killing a buffer.
   If any of these functions returns nil, we don't kill it.  */
Lisp_Object Vkill_buffer_query_functions;

Jim Blandy's avatar
Jim Blandy committed
150 151
/* List of functions to call before changing an unmodified buffer.  */
Lisp_Object Vfirst_change_hook;
152

Jim Blandy's avatar
Jim Blandy committed
153
Lisp_Object Qfirst_change_hook;
154 155
Lisp_Object Qbefore_change_functions;
Lisp_Object Qafter_change_functions;
Roland McGrath's avatar
Roland McGrath committed
156

157 158 159
/* If nonzero, all modification hooks are suppressed.  */
int inhibit_modification_hooks;

Roland McGrath's avatar
Roland McGrath committed
160 161 162 163 164 165 166 167
Lisp_Object Qfundamental_mode, Qmode_class, Qpermanent_local;

Lisp_Object Qprotected_field;

Lisp_Object QSFundamental;	/* A string "Fundamental" */

Lisp_Object Qkill_buffer_hook;

Richard M. Stallman's avatar
Richard M. Stallman committed
168 169
Lisp_Object Qget_file_buffer;

Jim Blandy's avatar
Jim Blandy committed
170 171
Lisp_Object Qoverlayp;

172
Lisp_Object Qpriority, Qwindow, Qevaporate, Qbefore_string, Qafter_string;
173

174 175 176 177
Lisp_Object Qmodification_hooks;
Lisp_Object Qinsert_in_front_hooks;
Lisp_Object Qinsert_behind_hooks;

Roland McGrath's avatar
Roland McGrath committed
178 179 180
/* For debugging; temporary.  See set_buffer_internal.  */
/* Lisp_Object Qlisp_mode, Vcheck_symbol; */

181
void
Roland McGrath's avatar
Roland McGrath committed
182 183 184
nsberror (spec)
     Lisp_Object spec;
{
185
  if (STRINGP (spec))
Roland McGrath's avatar
Roland McGrath committed
186 187 188 189
    error ("No buffer named %s", XSTRING (spec)->data);
  error ("Invalid buffer argument");
}

190 191 192 193 194 195 196 197 198 199
DEFUN ("buffer-live-p", Fbuffer_live_p, Sbuffer_live_p, 1, 1, 0,
  "Return non-nil if OBJECT is a buffer which has not been killed.\n\
Value is nil if OBJECT is not a buffer or if it has been killed.")
  (object)
     Lisp_Object object;
{
  return ((BUFFERP (object) && ! NILP (XBUFFER (object)->name))
	  ? Qt : Qnil);
}

200 201 202 203 204
DEFUN ("buffer-list", Fbuffer_list, Sbuffer_list, 0, 1, 0,
  "Return a list of all existing live buffers.\n\
If the optional arg FRAME is a frame, we return that frame's buffer list.")
  (frame)
     Lisp_Object frame;
Roland McGrath's avatar
Roland McGrath committed
205
{
206 207 208 209 210 211 212 213 214 215 216 217 218 219 220
  Lisp_Object framelist, general;
  general = Fmapcar (Qcdr, Vbuffer_alist);

  if (FRAMEP (frame))
    {
      Lisp_Object tail;

      CHECK_FRAME (frame, 1);

      framelist = Fcopy_sequence (XFRAME (frame)->buffer_list);

      /* Remove from GENERAL any buffer that duplicates one in FRAMELIST.  */
      tail = framelist;
      while (! NILP (tail))
	{
221 222
	  general = Fdelq (XCAR (tail), general);
	  tail = XCDR (tail);
223 224 225 226 227
	}
      return nconc2 (framelist, general);
    }

  return general;
Roland McGrath's avatar
Roland McGrath committed
228 229
}

230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250
/* Like Fassoc, but use Fstring_equal to compare
   (which ignores text properties),
   and don't ever QUIT.  */

static Lisp_Object
assoc_ignore_text_properties (key, list)
     register Lisp_Object key;
     Lisp_Object list;
{
  register Lisp_Object tail;
  for (tail = list; !NILP (tail); tail = Fcdr (tail))
    {
      register Lisp_Object elt, tem;
      elt = Fcar (tail);
      tem = Fstring_equal (Fcar (elt), key);
      if (!NILP (tem))
	return elt;
    }
  return Qnil;
}

Roland McGrath's avatar
Roland McGrath committed
251 252 253 254 255 256 257
DEFUN ("get-buffer", Fget_buffer, Sget_buffer, 1, 1, 0,
  "Return the buffer named NAME (a string).\n\
If there is no live buffer named NAME, return nil.\n\
NAME may also be a buffer; if so, the value is that buffer.")
  (name)
     register Lisp_Object name;
{
258
  if (BUFFERP (name))
Roland McGrath's avatar
Roland McGrath committed
259 260 261
    return name;
  CHECK_STRING (name, 0);

262
  return Fcdr (assoc_ignore_text_properties (name, Vbuffer_alist));
Roland McGrath's avatar
Roland McGrath committed
263 264 265 266
}

DEFUN ("get-file-buffer", Fget_file_buffer, Sget_file_buffer, 1, 1, 0,
  "Return the buffer visiting file FILENAME (a string).\n\
Karl Heuer's avatar
Karl Heuer committed
267
The buffer's `buffer-file-name' must match exactly the expansion of FILENAME.\n\
268 269
If there is no such live buffer, return nil.\n\
See also `find-buffer-visiting'.")
Roland McGrath's avatar
Roland McGrath committed
270 271 272 273
  (filename)
     register Lisp_Object filename;
{
  register Lisp_Object tail, buf, tem;
Richard M. Stallman's avatar
Richard M. Stallman committed
274 275
  Lisp_Object handler;

Roland McGrath's avatar
Roland McGrath committed
276 277 278
  CHECK_STRING (filename, 0);
  filename = Fexpand_file_name (filename, Qnil);

Richard M. Stallman's avatar
Richard M. Stallman committed
279 280
  /* If the file name has special constructs in it,
     call the corresponding file handler.  */
281
  handler = Ffind_file_name_handler (filename, Qget_file_buffer);
Richard M. Stallman's avatar
Richard M. Stallman committed
282 283 284
  if (!NILP (handler))
    return call2 (handler, Qget_file_buffer, filename);

285
  for (tail = Vbuffer_alist; CONSP (tail); tail = XCDR (tail))
Roland McGrath's avatar
Roland McGrath committed
286
    {
287
      buf = Fcdr (XCAR (tail));
288 289
      if (!BUFFERP (buf)) continue;
      if (!STRINGP (XBUFFER (buf)->filename)) continue;
Roland McGrath's avatar
Roland McGrath committed
290
      tem = Fstring_equal (XBUFFER (buf)->filename, filename);
Jim Blandy's avatar
Jim Blandy committed
291
      if (!NILP (tem))
Roland McGrath's avatar
Roland McGrath committed
292 293 294 295 296
	return buf;
    }
  return Qnil;
}

297 298 299 300 301 302
Lisp_Object
get_truename_buffer (filename)
     register Lisp_Object filename;
{
  register Lisp_Object tail, buf, tem;

303
  for (tail = Vbuffer_alist; CONSP (tail); tail = XCDR (tail))
304
    {
305
      buf = Fcdr (XCAR (tail));
306 307 308 309 310 311 312 313 314
      if (!BUFFERP (buf)) continue;
      if (!STRINGP (XBUFFER (buf)->file_truename)) continue;
      tem = Fstring_equal (XBUFFER (buf)->file_truename, filename);
      if (!NILP (tem))
	return buf;
    }
  return Qnil;
}

Roland McGrath's avatar
Roland McGrath committed
315 316 317 318 319 320
/* Incremented for each buffer created, to assign the buffer number. */
int buffer_count;

DEFUN ("get-buffer-create", Fget_buffer_create, Sget_buffer_create, 1, 1, 0,
  "Return the buffer named NAME, or create such a buffer and return it.\n\
A new buffer is created if there is no live buffer named NAME.\n\
321
If NAME starts with a space, the new buffer does not keep undo information.\n\
Roland McGrath's avatar
Roland McGrath committed
322 323 324 325 326
If NAME is a buffer instead of a string, then it is the value returned.\n\
The value is never nil.")  
  (name)
     register Lisp_Object name;
{
327
  register Lisp_Object buf;
Roland McGrath's avatar
Roland McGrath committed
328 329 330
  register struct buffer *b;

  buf = Fget_buffer (name);
Jim Blandy's avatar
Jim Blandy committed
331
  if (!NILP (buf))
Roland McGrath's avatar
Roland McGrath committed
332 333
    return buf;

334 335 336
  if (XSTRING (name)->size == 0)
    error ("Empty string for buffer name is not allowed");

337
  b = (struct buffer *) allocate_buffer ();
Roland McGrath's avatar
Roland McGrath committed
338

339 340 341 342 343 344
  b->size = sizeof (struct buffer) / sizeof (EMACS_INT);

  /* An ordinary buffer uses its own struct buffer_text.  */
  b->text = &b->own_text;
  b->base_buffer = 0;

Roland McGrath's avatar
Roland McGrath committed
345
  BUF_GAP_SIZE (b) = 20;
346
  BLOCK_INPUT;
Karl Heuer's avatar
Karl Heuer committed
347 348 349
  /* We allocate extra 1-byte at the tail and keep it always '\0' for
     anchoring a search.  */
  BUFFER_ALLOC (BUF_BEG_ADDR (b), (BUF_GAP_SIZE (b) + 1));
350
  UNBLOCK_INPUT;
Roland McGrath's avatar
Roland McGrath committed
351
  if (! BUF_BEG_ADDR (b))
352
    buffer_memory_full ();
Roland McGrath's avatar
Roland McGrath committed
353 354 355 356 357 358

  BUF_PT (b) = 1;
  BUF_GPT (b) = 1;
  BUF_BEGV (b) = 1;
  BUF_ZV (b) = 1;
  BUF_Z (b) = 1;
359 360 361 362 363
  BUF_PT_BYTE (b) = 1;
  BUF_GPT_BYTE (b) = 1;
  BUF_BEGV_BYTE (b) = 1;
  BUF_ZV_BYTE (b) = 1;
  BUF_Z_BYTE (b) = 1;
Roland McGrath's avatar
Roland McGrath committed
364
  BUF_MODIFF (b) = 1;
365
  BUF_OVERLAY_MODIFF (b) = 1;
366 367
  BUF_SAVE_MODIFF (b) = 1;
  BUF_INTERVALS (b) = 0;
368 369 370 371
  BUF_UNCHANGED_MODIFIED (b) = 1;
  BUF_OVERLAY_UNCHANGED_MODIFIED (b) = 1;
  BUF_END_UNCHANGED (b) = 0;
  BUF_BEG_UNCHANGED (b) = 0;
Karl Heuer's avatar
Karl Heuer committed
372
  *(BUF_GPT_ADDR (b)) = *(BUF_Z_ADDR (b)) = 0; /* Put an anchor '\0'.  */
Roland McGrath's avatar
Roland McGrath committed
373

374 375 376
  b->newline_cache = 0;
  b->width_run_cache = 0;
  b->width_table = Qnil;
377
  b->prevent_redisplay_optimizations_p = 1;
378

Roland McGrath's avatar
Roland McGrath committed
379 380 381 382
  /* Put this on the chain of all buffers including killed ones.  */
  b->next = all_buffers;
  all_buffers = b;

383 384 385 386 387
  /* An ordinary buffer normally doesn't need markers
     to handle BEGV and ZV.  */
  b->pt_marker = Qnil;
  b->begv_marker = Qnil;
  b->zv_marker = Qnil;
388 389 390

  name = Fcopy_sequence (name);
  INITIALIZE_INTERVAL (XSTRING (name), NULL_INTERVAL);
Roland McGrath's avatar
Roland McGrath committed
391
  b->name = name;
392

Roland McGrath's avatar
Roland McGrath committed
393 394 395 396 397 398
  if (XSTRING (name)->data[0] != ' ')
    b->undo_list = Qnil;
  else
    b->undo_list = Qt;

  reset_buffer (b);
399
  reset_buffer_local_variables (b, 1);
Roland McGrath's avatar
Roland McGrath committed
400 401

  /* Put this in the alist of all live buffers.  */
402
  XSETBUFFER (buf, b);
Roland McGrath's avatar
Roland McGrath committed
403 404 405
  Vbuffer_alist = nconc2 (Vbuffer_alist, Fcons (Fcons (name, buf), Qnil));

  b->mark = Fmake_marker ();
406 407 408 409 410
  BUF_MARKERS (b) = Qnil;
  b->name = name;
  return buf;
}

411
DEFUN ("make-indirect-buffer", Fmake_indirect_buffer, Smake_indirect_buffer, 2, 2,
412
       "bMake indirect buffer (to buffer): \nBName of indirect buffer: ",
413 414
  "Create and return an indirect buffer for buffer BASE-BUFFER, named NAME.\n\
BASE-BUFFER should be an existing buffer (or buffer name).\n\
415 416 417
NAME should be a string which is not the name of an existing buffer.")
  (base_buffer, name)
     register Lisp_Object base_buffer, name;
418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433
{
  register Lisp_Object buf;
  register struct buffer *b;

  buf = Fget_buffer (name);
  if (!NILP (buf))
    error ("Buffer name `%s' is in use", XSTRING (name)->data);

  base_buffer = Fget_buffer (base_buffer);
  if (NILP (base_buffer))
    error ("No such buffer: `%s'",
	   XSTRING (XBUFFER (base_buffer)->name)->data);

  if (XSTRING (name)->size == 0)
    error ("Empty string for buffer name is not allowed");

434
  b = (struct buffer *) allocate_buffer ();
435 436 437 438 439 440 441 442 443 444 445 446 447
  b->size = sizeof (struct buffer) / sizeof (EMACS_INT);

  if (XBUFFER (base_buffer)->base_buffer)
    b->base_buffer = XBUFFER (base_buffer)->base_buffer;
  else
    b->base_buffer = XBUFFER (base_buffer);

  /* Use the base buffer's text object.  */
  b->text = b->base_buffer->text;

  BUF_BEGV (b) = BUF_BEGV (b->base_buffer);
  BUF_ZV (b) = BUF_ZV (b->base_buffer);
  BUF_PT (b) = BUF_PT (b->base_buffer);
448 449 450
  BUF_BEGV_BYTE (b) = BUF_BEGV_BYTE (b->base_buffer);
  BUF_ZV_BYTE (b) = BUF_ZV_BYTE (b->base_buffer);
  BUF_PT_BYTE (b) = BUF_PT_BYTE (b->base_buffer);
451 452 453 454 455 456 457 458 459 460 461 462 463 464

  b->newline_cache = 0;
  b->width_run_cache = 0;
  b->width_table = Qnil;

  /* Put this on the chain of all buffers including killed ones.  */
  b->next = all_buffers;
  all_buffers = b;

  name = Fcopy_sequence (name);
  INITIALIZE_INTERVAL (XSTRING (name), NULL_INTERVAL);
  b->name = name;

  reset_buffer (b);
465
  reset_buffer_local_variables (b, 1);
466 467 468 469 470 471

  /* Put this in the alist of all live buffers.  */
  XSETBUFFER (buf, b);
  Vbuffer_alist = nconc2 (Vbuffer_alist, Fcons (Fcons (name, buf), Qnil));

  b->mark = Fmake_marker ();
Roland McGrath's avatar
Roland McGrath committed
472
  b->name = name;
473

474 475 476
  /* The multibyte status belongs to the base buffer.  */
  b->enable_multibyte_characters = b->base_buffer->enable_multibyte_characters;

477 478 479 480
  /* Make sure the base buffer has markers for its narrowing.  */
  if (NILP (b->base_buffer->pt_marker))
    {
      b->base_buffer->pt_marker = Fmake_marker ();
481 482 483
      set_marker_both (b->base_buffer->pt_marker, base_buffer,
		       BUF_PT (b->base_buffer),
		       BUF_PT_BYTE (b->base_buffer));
484 485 486 487
    }
  if (NILP (b->base_buffer->begv_marker))
    {
      b->base_buffer->begv_marker = Fmake_marker ();
488 489 490
      set_marker_both (b->base_buffer->begv_marker, base_buffer,
		       BUF_BEGV (b->base_buffer),
		       BUF_BEGV_BYTE (b->base_buffer));
491 492 493 494
    }
  if (NILP (b->base_buffer->zv_marker))
    {
      b->base_buffer->zv_marker = Fmake_marker ();
495 496 497
      set_marker_both (b->base_buffer->zv_marker, base_buffer,
		       BUF_ZV (b->base_buffer),
		       BUF_ZV_BYTE (b->base_buffer));
498
      XMARKER (b->base_buffer->zv_marker)->insertion_type = 1;
499 500 501
    }

  /* Give the indirect buffer markers for its narrowing.  */
502
  b->pt_marker = Fmake_marker ();
503
  set_marker_both (b->pt_marker, buf, BUF_PT (b), BUF_PT_BYTE (b));
504
  b->begv_marker = Fmake_marker ();
505
  set_marker_both (b->begv_marker, buf, BUF_BEGV (b), BUF_BEGV_BYTE (b));
506
  b->zv_marker = Fmake_marker ();
507
  set_marker_both (b->zv_marker, buf, BUF_ZV (b), BUF_ZV_BYTE (b));
508
  XMARKER (b->zv_marker)->insertion_type = 1;
509

510
  return buf;
Roland McGrath's avatar
Roland McGrath committed
511 512
}

513 514
/* Reinitialize everything about a buffer except its name and contents
   and local variables.  */
Roland McGrath's avatar
Roland McGrath committed
515 516 517 518 519 520

void
reset_buffer (b)
     register struct buffer *b;
{
  b->filename = Qnil;
521
  b->file_truename = Qnil;
Roland McGrath's avatar
Roland McGrath committed
522 523
  b->directory = (current_buffer) ? current_buffer->directory : Qnil;
  b->modtime = 0;
524
  XSETFASTINT (b->save_length, 0);
Roland McGrath's avatar
Roland McGrath committed
525
  b->last_window_start = 1;
526
  /* It is more conservative to start out "changed" than "unchanged".  */
527 528
  b->clip_changed = 0;
  b->prevent_redisplay_optimizations_p = 1;
Roland McGrath's avatar
Roland McGrath committed
529 530
  b->backed_up = Qnil;
  b->auto_save_modified = 0;
531
  b->auto_save_failure_time = -1;
Roland McGrath's avatar
Roland McGrath committed
532 533
  b->auto_save_file_name = Qnil;
  b->read_only = Qnil;
534 535
  b->overlays_before = Qnil;
  b->overlays_after = Qnil;
536
  XSETFASTINT (b->overlay_center, 1);
537
  b->mark_active = Qnil;
538
  b->point_before_scroll = Qnil;
539
  b->file_format = Qnil;
540
  b->last_selected_window = Qnil;
541
  XSETINT (b->display_count, 0);
542
  b->display_time = Qnil;
543 544
  b->extra2 = Qnil;
  b->extra3 = Qnil;
545
  b->enable_multibyte_characters = buffer_defaults.enable_multibyte_characters;
546
  b->cursor_type = buffer_defaults.cursor_type;
Roland McGrath's avatar
Roland McGrath committed
547 548
}

549 550 551
/* Reset buffer B's local variables info.
   Don't use this on a buffer that has already been in use;
   it does not treat permanent locals consistently.
552 553 554 555 556
   Instead, use Fkill_all_local_variables.

   If PERMANENT_TOO is 1, then we reset permanent built-in
   buffer-local variables.  If PERMANENT_TOO is 0,
   we preserve those.  */
557

558 559
static void
reset_buffer_local_variables (b, permanent_too)
Roland McGrath's avatar
Roland McGrath committed
560
     register struct buffer *b;
561
     int permanent_too;
Roland McGrath's avatar
Roland McGrath committed
562 563
{
  register int offset;
564
  int i;
Roland McGrath's avatar
Roland McGrath committed
565 566 567 568 569 570 571 572 573 574

  /* Reset the major mode to Fundamental, together with all the
     things that depend on the major mode.
     default-major-mode is handled at a higher level.
     We ignore it here.  */
  b->major_mode = Qfundamental_mode;
  b->keymap = Qnil;
  b->abbrev_table = Vfundamental_mode_abbrev_table;
  b->mode_name = QSFundamental;
  b->minor_modes = Qnil;
575 576 577 578 579 580 581 582

  /* If the standard case table has been altered and invalidated,
     fix up its insides first.  */
  if (! (CHAR_TABLE_P (XCHAR_TABLE (Vascii_downcase_table)->extras[0])
	 && CHAR_TABLE_P (XCHAR_TABLE (Vascii_downcase_table)->extras[1])
	 && CHAR_TABLE_P (XCHAR_TABLE (Vascii_downcase_table)->extras[2])))
    Fset_standard_case_table (Vascii_downcase_table);

Roland McGrath's avatar
Roland McGrath committed
583
  b->downcase_table = Vascii_downcase_table;
584 585 586
  b->upcase_table = XCHAR_TABLE (Vascii_downcase_table)->extras[0];
  b->case_canon_table = XCHAR_TABLE (Vascii_downcase_table)->extras[1];
  b->case_eqv_table = XCHAR_TABLE (Vascii_downcase_table)->extras[2];
587
  b->invisibility_spec = Qt;
588 589 590
#ifndef DOS_NT
  b->buffer_file_type = Qnil;
#endif
591

Roland McGrath's avatar
Roland McGrath committed
592 593 594 595 596
#if 0
  b->sort_table = XSTRING (Vascii_sort_table);
  b->folding_sort_table = XSTRING (Vascii_folding_sort_table);
#endif /* 0 */

597
  /* Reset all (or most) per-buffer variables to their defaults.  */
Roland McGrath's avatar
Roland McGrath committed
598
  b->local_var_alist = Qnil;
599
  for (i = 0; i < last_per_buffer_idx; ++i)
600
    if (permanent_too || buffer_permanent_local_flags[i] == 0)
601
      SET_PER_BUFFER_VALUE_P (b, i, 0);
Roland McGrath's avatar
Roland McGrath committed
602 603 604 605

  /* For each slot that has a default value,
     copy that into the slot.  */

606
  for (offset = PER_BUFFER_VAR_OFFSET (name);
607 608
       offset < sizeof *b;
       offset += sizeof (Lisp_Object))
609
    {
610
      int idx = PER_BUFFER_IDX (offset);
611 612 613 614 615
      if ((idx > 0
	   && (permanent_too
	       || buffer_permanent_local_flags[idx] == 0))
	  /* Is -2 used anywhere?  */
	  || idx == -2)
616
	PER_BUFFER_VALUE (b, offset) = PER_BUFFER_DEFAULT (offset);
617
    }
Roland McGrath's avatar
Roland McGrath committed
618 619
}

Roland McGrath's avatar
Roland McGrath committed
620 621 622 623 624
/* We split this away from generate-new-buffer, because rename-buffer
   and set-visited-file-name ought to be able to use this to really
   rename the buffer properly.  */

DEFUN ("generate-new-buffer-name", Fgenerate_new_buffer_name, Sgenerate_new_buffer_name,
625
  1, 2, 0,
Roland McGrath's avatar
Roland McGrath committed
626 627
  "Return a string that is the name of no existing buffer based on NAME.\n\
If there is no live buffer named NAME, then return NAME.\n\
Roland McGrath's avatar
Roland McGrath committed
628
Otherwise modify name by appending `<NUMBER>', incrementing NUMBER\n\
629
until an unused name is found, and then return that name.\n\
630
Optional second argument IGNORE specifies a name that is okay to use\n\
631
\(if it is in the sequence to be tried)\n\
632
even if a buffer with that name exists.")
633 634
 (name, ignore)
     register Lisp_Object name, ignore;
Roland McGrath's avatar
Roland McGrath committed
635 636 637 638 639 640 641 642
{
  register Lisp_Object gentemp, tem;
  int count;
  char number[10];

  CHECK_STRING (name, 0);

  tem = Fget_buffer (name);
Jim Blandy's avatar
Jim Blandy committed
643
  if (NILP (tem))
Roland McGrath's avatar
Roland McGrath committed
644
    return name;
Roland McGrath's avatar
Roland McGrath committed
645 646 647 648 649 650

  count = 1;
  while (1)
    {
      sprintf (number, "<%d>", ++count);
      gentemp = concat2 (name, build_string (number));
651
      tem = Fstring_equal (gentemp, ignore);
652 653
      if (!NILP (tem))
	return gentemp;
Roland McGrath's avatar
Roland McGrath committed
654
      tem = Fget_buffer (gentemp);
Jim Blandy's avatar
Jim Blandy committed
655
      if (NILP (tem))
Roland McGrath's avatar
Roland McGrath committed
656
	return gentemp;
Roland McGrath's avatar
Roland McGrath committed
657 658 659 660 661 662
    }
}


DEFUN ("buffer-name", Fbuffer_name, Sbuffer_name, 0, 1, 0,
  "Return the name of BUFFER, as a string.\n\
Roland McGrath's avatar
Roland McGrath committed
663
With no argument or nil as argument, return the name of the current buffer.")
Roland McGrath's avatar
Roland McGrath committed
664 665 666
  (buffer)
     register Lisp_Object buffer;
{
Jim Blandy's avatar
Jim Blandy committed
667
  if (NILP (buffer))
Roland McGrath's avatar
Roland McGrath committed
668 669 670 671 672 673 674 675 676 677 678
    return current_buffer->name;
  CHECK_BUFFER (buffer, 0);
  return XBUFFER (buffer)->name;
}

DEFUN ("buffer-file-name", Fbuffer_file_name, Sbuffer_file_name, 0, 1, 0,
  "Return name of file BUFFER is visiting, or nil if none.\n\
No argument or nil as argument means use the current buffer.")
  (buffer)
     register Lisp_Object buffer;
{
Jim Blandy's avatar
Jim Blandy committed
679
  if (NILP (buffer))
Roland McGrath's avatar
Roland McGrath committed
680 681 682 683 684
    return current_buffer->filename;
  CHECK_BUFFER (buffer, 0);
  return XBUFFER (buffer)->filename;
}

685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708
DEFUN ("buffer-base-buffer", Fbuffer_base_buffer, Sbuffer_base_buffer,
       0, 1, 0,
  "Return the base buffer of indirect buffer BUFFER.\n\
If BUFFER is not indirect, return nil.")
  (buffer)
     register Lisp_Object buffer;
{
  struct buffer *base;
  Lisp_Object base_buffer;

  if (NILP (buffer))
    base = current_buffer->base_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      base = XBUFFER (buffer)->base_buffer;
    }

  if (! base)
    return Qnil;
  XSETBUFFER (base_buffer, base);
  return base_buffer;
}

Roland McGrath's avatar
Roland McGrath committed
709 710 711
DEFUN ("buffer-local-variables", Fbuffer_local_variables,
  Sbuffer_local_variables, 0, 1, 0,
  "Return an alist of variables that are buffer-local in BUFFER.\n\
712 713
Most elements look like (SYMBOL . VALUE), describing one variable.\n\
For a symbol that is locally unbound, just the symbol appears in the value.\n\
Roland McGrath's avatar
Roland McGrath committed
714 715 716 717 718 719
Note that storing new VALUEs in these elements doesn't change the variables.\n\
No argument or nil as argument means use current buffer as BUFFER.")
  (buffer)
     register Lisp_Object buffer;
{
  register struct buffer *buf;
720
  register Lisp_Object result;
Roland McGrath's avatar
Roland McGrath committed
721

Jim Blandy's avatar
Jim Blandy committed
722
  if (NILP (buffer))
Roland McGrath's avatar
Roland McGrath committed
723 724 725 726 727 728 729
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

730 731
  result = Qnil;

Roland McGrath's avatar
Roland McGrath committed
732
  {
733
    register Lisp_Object tail;
734
    for (tail = buf->local_var_alist; CONSP (tail); tail = XCDR (tail))
Roland McGrath's avatar
Roland McGrath committed
735
      {
736 737
	Lisp_Object val, elt;

738
	elt = XCAR (tail);
739

740 741 742 743 744
	/* Reference each variable in the alist in buf.
	   If inquiring about the current buffer, this gets the current values,
	   so store them into the alist so the alist is up to date.
	   If inquiring about some other buffer, this swaps out any values
	   for that buffer, making the alist up to date automatically.  */
745
	val = find_symbol_value (XCAR (elt));
746 747
	/* Use the current buffer value only if buf is the current buffer.  */
	if (buf != current_buffer)
748
	  val = XCDR (elt);
749 750 751

	/* If symbol is unbound, put just the symbol in the list.  */
	if (EQ (val, Qunbound))
752
	  result = Fcons (XCAR (elt), result);
753 754
	/* Otherwise, put (symbol . value) in the list.  */
	else
755
	  result = Fcons (Fcons (XCAR (elt), val), result);
Roland McGrath's avatar
Roland McGrath committed
756 757 758 759 760
      }
  }

  /* Add on all the variables stored in special slots.  */
  {
761
    int offset, idx;
Roland McGrath's avatar
Roland McGrath committed
762

763
    for (offset = PER_BUFFER_VAR_OFFSET (name);
Roland McGrath's avatar
Roland McGrath committed
764
	 offset < sizeof (struct buffer);
765 766
	 /* sizeof EMACS_INT == sizeof Lisp_Object */
	 offset += (sizeof (EMACS_INT)))
Roland McGrath's avatar
Roland McGrath committed
767
      {
768 769 770 771 772
	idx = PER_BUFFER_IDX (offset);
	if ((idx == -1 || PER_BUFFER_VALUE_P (buf, idx))
	    && SYMBOLP (PER_BUFFER_SYMBOL (offset)))
	  result = Fcons (Fcons (PER_BUFFER_SYMBOL (offset),
				 PER_BUFFER_VALUE (buf, offset)),
773
			  result);
Roland McGrath's avatar
Roland McGrath committed
774 775
      }
  }
776 777

  return result;
Roland McGrath's avatar
Roland McGrath committed
778 779 780 781 782 783 784 785 786 787 788
}


DEFUN ("buffer-modified-p", Fbuffer_modified_p, Sbuffer_modified_p,
  0, 1, 0,
  "Return t if BUFFER was modified since its file was last read or saved.\n\
No argument or nil as argument means use current buffer as BUFFER.")
  (buffer)
     register Lisp_Object buffer;
{
  register struct buffer *buf;
Jim Blandy's avatar
Jim Blandy committed
789
  if (NILP (buffer))
Roland McGrath's avatar
Roland McGrath committed
790 791 792 793 794 795 796
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

797
  return BUF_SAVE_MODIFF (buf) < BUF_MODIFF (buf) ? Qt : Qnil;
Roland McGrath's avatar
Roland McGrath committed
798 799 800 801 802 803 804 805 806 807 808
}

DEFUN ("set-buffer-modified-p", Fset_buffer_modified_p, Sset_buffer_modified_p,
  1, 1, 0,
  "Mark current buffer as modified or unmodified according to FLAG.\n\
A non-nil FLAG means mark the buffer modified.")
  (flag)
     register Lisp_Object flag;
{
  register int already;
  register Lisp_Object fn;
809
  Lisp_Object buffer, window;
Roland McGrath's avatar
Roland McGrath committed
810 811 812 813 814

#ifdef CLASH_DETECTION
  /* If buffer becoming modified, lock the file.
     If buffer becoming unmodified, unlock the file.  */

815
  fn = current_buffer->file_truename;
816 817
  /* Test buffer-file-name so that binding it to nil is effective.  */
  if (!NILP (fn) && ! NILP (current_buffer->filename))
Roland McGrath's avatar
Roland McGrath committed
818
    {
819
      already = SAVE_MODIFF < MODIFF;
Jim Blandy's avatar
Jim Blandy committed
820
      if (!already && !NILP (flag))
Roland McGrath's avatar
Roland McGrath committed
821
	lock_file (fn);
Jim Blandy's avatar
Jim Blandy committed
822
      else if (already && NILP (flag))
Roland McGrath's avatar
Roland McGrath committed
823 824 825 826
	unlock_file (fn);
    }
#endif /* CLASH_DETECTION */

827
  SAVE_MODIFF = NILP (flag) ? MODIFF : 0;
828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844
  
  /* Set update_mode_lines only if buffer is displayed in some window.
     Packages like jit-lock or lazy-lock preserve a buffer's modified
     state by recording/restoring the state around blocks of code.
     Setting update_mode_lines makes redisplay consider all windows
     (on all frames).  Stealth fontification of buffers not displayed
     would incur additional redisplay costs if we'd set
     update_modes_lines unconditionally.

     Ideally, I think there should be another mechanism for fontifying
     buffers without "modifying" buffers, or redisplay should be
     smarter about updating the `*' in mode lines.  --gerd  */
  XSETBUFFER (buffer, current_buffer);
  window = Fget_buffer_window (buffer, Qt);
  if (WINDOWP (window))
    update_mode_lines++;
  
Roland McGrath's avatar
Roland McGrath committed
845 846 847
  return flag;
}

848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877
DEFUN ("restore-buffer-modified-p", Frestore_buffer_modified_p,
       Srestore_buffer_modified_p, 1, 1, 0,
   "Like `set-buffer-modified-p', with a differences concerning redisplay.\n\
It is not ensured that mode lines will be updated to show the modified\n\
state of the current buffer.  Use with care.")
  (flag)
     Lisp_Object flag;
{
#ifdef CLASH_DETECTION
  Lisp_Object fn;
  
  /* If buffer becoming modified, lock the file.
     If buffer becoming unmodified, unlock the file.  */

  fn = current_buffer->file_truename;
  /* Test buffer-file-name so that binding it to nil is effective.  */
  if (!NILP (fn) && ! NILP (current_buffer->filename))
    {
      int already = SAVE_MODIFF < MODIFF;
      if (!already && !NILP (flag))
	lock_file (fn);
      else if (already && NILP (flag))
	unlock_file (fn);
    }
#endif /* CLASH_DETECTION */
  
  SAVE_MODIFF = NILP (flag) ? MODIFF : 0;
  return flag;
}

Roland McGrath's avatar
Roland McGrath committed
878 879 880 881 882 883 884 885 886 887
DEFUN ("buffer-modified-tick", Fbuffer_modified_tick, Sbuffer_modified_tick,
  0, 1, 0,
  "Return BUFFER's tick counter, incremented for each change in text.\n\
Each buffer has a tick counter which is incremented each time the text in\n\
that buffer is changed.  It wraps around occasionally.\n\
No argument or nil as argument means use current buffer as BUFFER.")
  (buffer)
     register Lisp_Object buffer;
{
  register struct buffer *buf;
Jim Blandy's avatar
Jim Blandy committed
888
  if (NILP (buffer))
Roland McGrath's avatar
Roland McGrath committed
889 890 891 892 893 894 895 896 897 898
    buf = current_buffer;
  else
    {
      CHECK_BUFFER (buffer, 0);
      buf = XBUFFER (buffer);
    }

  return make_number (BUF_MODIFF (buf));
}

Roland McGrath's avatar
Roland McGrath committed
899
DEFUN ("rename-buffer", Frename_buffer, Srename_buffer, 1, 2,
900
       "sRename buffer (to new name): \nP",
Roland McGrath's avatar
Roland McGrath committed
901
  "Change current buffer's name to NEWNAME (a string).\n\
902
If second arg UNIQUE is nil or omitted, it is an error if a\n\
Roland McGrath's avatar
Roland McGrath committed
903
buffer named NEWNAME already exists.\n\
904
If UNIQUE is non-nil, come up with a new name using\n\
Roland McGrath's avatar
Roland McGrath committed
905
`generate-new-buffer-name'.\n\
906 907
Interactively, you can set UNIQUE with a prefix argument.\n\
We return the name we actually gave the buffer.\n\
Roland McGrath's avatar
Roland McGrath committed
908
This does not change the name of the visited file (if any).")
909 910
  (newname, unique)
     register Lisp_Object newname, unique;
Roland McGrath's avatar
Roland McGrath committed
911 912 913
{
  register Lisp_Object tem, buf;

914
  CHECK_STRING (newname, 0);
915

916
  if (XSTRING (newname)->size == 0)
917 918
    error ("Empty string is invalid as a buffer name");

919
  tem = Fget_buffer (newname);
Jim Blandy's avatar
Jim Blandy committed
920
  if (!NILP (tem))
Roland McGrath's avatar
Roland McGrath committed
921
    {
922 923 924 925 926 927
      /* Don't short-circuit if UNIQUE is t.  That is a useful way to
	 rename the buffer automatically so you can create another
	 with the original name.  It makes UNIQUE equivalent to
	 (rename-buffer (generate-new-buffer-name NEWNAME)).  */
      if (NILP (unique) && XBUFFER (tem) == current_buffer)
	return current_buffer->name;
928
      if (!NILP (unique))
929
	newname = Fgenerate_new_buffer_name (newname, current_buffer->name);
Roland McGrath's avatar
Roland McGrath committed
930
      else
931
	error ("Buffer name `%s' is in use", XSTRING (newname)->data);
Roland McGrath's avatar
Roland McGrath committed
932
    }
Roland McGrath's avatar
Roland McGrath committed
933

934
  current_buffer->name = newname;
935 936 937 938 939

  /* Catch redisplay's attention.  Unless we do this, the mode lines for
     any windows displaying current_buffer will stay unchanged.  */
  update_mode_lines++;

940
  XSETBUFFER (buf, current_buffer);
941
  Fsetcar (Frassq (buf, Vbuffer_alist), newname);
942 943
  if (NILP (current_buffer->filename)
      && !NILP (current_buffer->auto_save_file_name))
Roland McGrath's avatar
Roland McGrath committed
944
    call0 (intern ("rename-auto-save-file"));
945 946
  /* Refetch since that last call may have done GC.  */
  return current_buffer->name;
Roland McGrath's avatar
Roland McGrath committed
947 948
}

949
DEFUN ("other-buffer", Fother_buffer, Sother_buffer, 0, 3, 0,
Roland McGrath's avatar
Roland McGrath committed
950
  "Return most recently selected buffer other than BUFFER.\n\
951 952
Buffers not visible in windows are preferred to visible buffers,\n\
unless optional second argument VISIBLE-OK is non-nil.\n\
953 954
If the optional third argument FRAME is non-nil, use that frame's\n\
buffer list instead of the selected frame's buffer list.\n\
Roland McGrath's avatar
Roland McGrath committed
955 956
If no other buffer exists, the buffer `*scratch*' is returned.\n\
If BUFFER is omitted or nil, some interesting buffer is returned.")
957 958
  (buffer, visible_ok, frame)
     register Lisp_Object buffer, visible_ok, frame;
Roland McGrath's avatar
Roland McGrath committed
959
{
960
  Lisp_Object Fset_buffer_major_mode ();
961
  register Lisp_Object tail, buf, notsogood, tem, pred, add_ons;
Roland McGrath's avatar
Roland McGrath committed
962 963
  notsogood = Qnil;

964
  if (NILP (frame))
965
    frame = selected_frame;
966

967
  tail = Vbuffer_alist;
968
  pred = frame_buffer_predicate (frame);
969 970 971 972

  /* Consider buffers that have been seen in the selected frame
     before other buffers.  */
    
973
  tem = frame_buffer_list (frame);
974 975 976
  add_ons = Qnil;
  while (CONSP (tem))
    {
977 978 979
      if (BUFFERP (XCAR (tem)))
	add_ons = Fcons (Fcons (Qnil, XCAR (tem)), add_ons);
      tem = XCDR (tem);
980 981 982 983
    }
  tail = nconc2 (Fnreverse (add_ons), tail);

  for (; !NILP (tail); tail = Fcdr (tail))
Roland McGrath's avatar
Roland McGrath committed
984 985 986 987 988 989
    {
      buf = Fcdr (Fcar (tail));
      if (EQ (buf, buffer))
	continue;
      if (XSTRING (XBUFFER (buf)->name)->data[0] == ' ')
	continue;
990 991
      /* If the selected frame has a buffer_predicate,
	 disregard buffers that don't fit the predicate.  */
992
      if (!NILP (pred))
993
	{
994
	  tem = call1 (pred, buf);
995 996 997 998
	  if (NILP (tem))
	    continue;
	}

999
      if (NILP (visible_ok))
1000
	tem = Fget_buffer_window (buf, Qt);
1001 1002
      else
	tem = Qnil;
Jim Blandy's avatar
Jim Blandy committed
1003