editfns.c 144 KB
Newer Older
Jim Blandy's avatar
Jim Blandy committed
1
/* Lisp functions pertaining to editing.
2 3
   Copyright (C) 1985, 1986, 1987, 1989, 1993, 1994, 1995, 1996,
                 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
4
                 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
Jim Blandy's avatar
Jim Blandy committed
5 6 7

This file is part of GNU Emacs.

8
GNU Emacs is free software: you can redistribute it and/or modify
Jim Blandy's avatar
Jim Blandy committed
9
it under the terms of the GNU General Public License as published by
10 11
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Jim Blandy's avatar
Jim Blandy committed
12 13 14 15 16 17 18

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
19
along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
Jim Blandy's avatar
Jim Blandy committed
20 21


22
#include <config.h>
23
#include <sys/types.h>
24
#include <stdio.h>
25
#include <setjmp.h>
Jim Blandy's avatar
Jim Blandy committed
26

27
#ifdef HAVE_PWD_H
Jim Blandy's avatar
Jim Blandy committed
28
#include <pwd.h>
Jim Blandy's avatar
Jim Blandy committed
29 30
#endif

Andreas Schwab's avatar
Andreas Schwab committed
31 32 33 34
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

35 36 37 38
#ifdef HAVE_SYS_UTSNAME_H
#include <sys/utsname.h>
#endif

39 40
#include "lisp.h"

41 42 43 44
/* systime.h includes <sys/time.h> which, on some systems, is required
   for <sys/resource.h>; thus systime.h must be included before
   <sys/resource.h> */
#include "systime.h"
45 46

#if defined HAVE_SYS_RESOURCE_H
47
#include <sys/resource.h>
48 49
#endif

50 51
#include <ctype.h>

52
#include "intervals.h"
Jim Blandy's avatar
Jim Blandy committed
53
#include "buffer.h"
54
#include "character.h"
55
#include "coding.h"
56
#include "frame.h"
Jim Blandy's avatar
Jim Blandy committed
57
#include "window.h"
YAMAMOTO Mitsuharu's avatar
YAMAMOTO Mitsuharu committed
58
#include "blockinput.h"
Jim Blandy's avatar
Jim Blandy committed
59

60 61 62 63 64 65 66
#ifdef STDC_HEADERS
#include <float.h>
#define MAX_10_EXP	DBL_MAX_10_EXP
#else
#define MAX_10_EXP	310
#endif

67 68 69 70
#ifndef NULL
#define NULL 0
#endif

71 72 73 74
#ifndef USER_FULL_NAME
#define USER_FULL_NAME pw->pw_gecos
#endif

75
#ifndef USE_CRT_DLL
76
extern char **environ;
77 78
#endif

79 80
#define TM_YEAR_BASE 1900

81 82 83 84 85 86 87
/* Nonzero if TM_YEAR is a struct tm's tm_year value that causes
   asctime to have well-defined behavior.  */
#ifndef TM_YEAR_IN_ASCTIME_RANGE
# define TM_YEAR_IN_ASCTIME_RANGE(tm_year) \
    (1000 - TM_YEAR_BASE <= (tm_year) && (tm_year) <= 9999 - TM_YEAR_BASE)
#endif

88 89
extern size_t emacs_strftimeu P_ ((char *, size_t, const char *,
				   const struct tm *, int));
90 91 92 93 94

#ifdef WINDOWSNT
extern Lisp_Object w32_get_internal_run_time ();
#endif

95
static int tm_diff P_ ((struct tm *, struct tm *));
96
static void find_field P_ ((Lisp_Object, Lisp_Object, Lisp_Object, int *, Lisp_Object, int *));
97 98
static void update_buffer_properties P_ ((int, int));
static Lisp_Object region_limit P_ ((int));
99
int lisp_time_argument P_ ((Lisp_Object, time_t *, int *));
100 101
static size_t emacs_memftimeu P_ ((char *, size_t, const char *,
				   size_t, const struct tm *, int));
102 103 104 105 106
static void general_insert_function (void (*) (const unsigned char *, EMACS_INT),
				     void (*) (Lisp_Object, EMACS_INT,
					       EMACS_INT, EMACS_INT,
					       EMACS_INT, int),
				     int, int, Lisp_Object *);
107 108 109
static Lisp_Object subst_char_in_region_unwind P_ ((Lisp_Object));
static Lisp_Object subst_char_in_region_unwind_1 P_ ((Lisp_Object));
static void transpose_markers P_ ((int, int, int, int, int, int, int, int));
110

Gerd Moellmann's avatar
Gerd Moellmann committed
111 112 113 114
#ifdef HAVE_INDEX
extern char *index P_ ((const char *, int));
#endif

115 116 117
Lisp_Object Vbuffer_access_fontify_functions;
Lisp_Object Qbuffer_access_fontify_functions;
Lisp_Object Vbuffer_access_fontified_property;
118

119
Lisp_Object Fuser_full_name P_ ((Lisp_Object));
120

121 122 123 124
/* Non-nil means don't stop at field boundary in text motion commands.  */

Lisp_Object Vinhibit_field_text_motion;

Jim Blandy's avatar
Jim Blandy committed
125 126 127
/* Some static data, and a function to initialize it for each run */

Lisp_Object Vsystem_name;
128 129 130
Lisp_Object Vuser_real_login_name;	/* login name of current user ID */
Lisp_Object Vuser_full_name;		/* full name of current user */
Lisp_Object Vuser_login_name;		/* user name from LOGNAME or USER */
131
Lisp_Object Voperating_system_release;  /* Operating System Release */
Jim Blandy's avatar
Jim Blandy committed
132

133 134 135 136 137 138 139 140 141
/* Symbol for the text property used to mark fields.  */

Lisp_Object Qfield;

/* A special value for Qfield properties.  */

Lisp_Object Qboundary;


Jim Blandy's avatar
Jim Blandy committed
142 143 144
void
init_editfns ()
{
Jim Blandy's avatar
Jim Blandy committed
145
  char *user_name;
146
  register unsigned char *p;
Jim Blandy's avatar
Jim Blandy committed
147 148 149 150
  struct passwd *pw;	/* password entry for the current user */
  Lisp_Object tem;

  /* Set up system_name even when dumping.  */
151
  init_system_name ();
Jim Blandy's avatar
Jim Blandy committed
152 153 154 155 156 157 158 159

#ifndef CANNOT_DUMP
  /* Don't bother with this on initial start when just dumping out */
  if (!initialized)
    return;
#endif /* not CANNOT_DUMP */

  pw = (struct passwd *) getpwuid (getuid ());
Morten Welinder's avatar
Morten Welinder committed
160 161 162 163
#ifdef MSDOS
  /* We let the real user name default to "root" because that's quite
     accurate on MSDOG and because it lets Emacs find the init file.
     (The DVX libraries override the Djgpp libraries here.)  */
164
  Vuser_real_login_name = build_string (pw ? pw->pw_name : "root");
Morten Welinder's avatar
Morten Welinder committed
165
#else
166
  Vuser_real_login_name = build_string (pw ? pw->pw_name : "unknown");
Morten Welinder's avatar
Morten Welinder committed
167
#endif
Jim Blandy's avatar
Jim Blandy committed
168

Jim Blandy's avatar
Jim Blandy committed
169 170
  /* Get the effective user name, by consulting environment variables,
     or the effective uid if those are unset.  */
171
  user_name = (char *) getenv ("LOGNAME");
Jim Blandy's avatar
Jim Blandy committed
172
  if (!user_name)
173 174 175
#ifdef WINDOWSNT
    user_name = (char *) getenv ("USERNAME");	/* it's USERNAME on NT */
#else  /* WINDOWSNT */
176
    user_name = (char *) getenv ("USER");
177
#endif /* WINDOWSNT */
Jim Blandy's avatar
Jim Blandy committed
178 179 180 181 182
  if (!user_name)
    {
      pw = (struct passwd *) getpwuid (geteuid ());
      user_name = (char *) (pw ? pw->pw_name : "unknown");
    }
183
  Vuser_login_name = build_string (user_name);
Jim Blandy's avatar
Jim Blandy committed
184

Jim Blandy's avatar
Jim Blandy committed
185 186
  /* If the user name claimed in the environment vars differs from
     the real uid, use the claimed name to find the full name.  */
187
  tem = Fstring_equal (Vuser_login_name, Vuser_real_login_name);
188 189
  Vuser_full_name = Fuser_full_name (NILP (tem)? make_number (geteuid())
				     : Vuser_login_name);
Sam Steingold's avatar
Sam Steingold committed
190

191
  p = (unsigned char *) getenv ("NAME");
192 193
  if (p)
    Vuser_full_name = build_string (p);
194 195
  else if (NILP (Vuser_full_name))
    Vuser_full_name = build_string ("unknown");
196 197 198 199 200 201 202 203 204 205

#ifdef HAVE_SYS_UTSNAME_H
  {
    struct utsname uts;
    uname (&uts);
    Voperating_system_release = build_string (uts.release);
  }
#else
  Voperating_system_release = Qnil;
#endif
Jim Blandy's avatar
Jim Blandy committed
206 207 208
}

DEFUN ("char-to-string", Fchar_to_string, Schar_to_string, 1, 1, 0,
209 210
       doc: /* Convert arg CHAR to a string containing that character.
usage: (char-to-string CHAR)  */)
211
     (character)
212
     Lisp_Object character;
Jim Blandy's avatar
Jim Blandy committed
213
{
Karl Heuer's avatar
Karl Heuer committed
214
  int len;
215
  unsigned char str[MAX_MULTIBYTE_LENGTH];
Karl Heuer's avatar
Karl Heuer committed
216

217
  CHECK_CHARACTER (character);
Jim Blandy's avatar
Jim Blandy committed
218

219
  len = CHAR_STRING (XFASTINT (character), str);
220
  return make_string_from_bytes (str, 1, len);
Jim Blandy's avatar
Jim Blandy committed
221 222
}

223 224 225 226 227 228 229 230 231 232
DEFUN ("byte-to-string", Fbyte_to_string, Sbyte_to_string, 1, 1, 0,
       doc: /* Convert arg BYTE to a string containing that byte.  */)
     (byte)
     Lisp_Object byte;
{
  CHECK_NUMBER (byte);
  unsigned char b = XINT (byte);
  return make_string_from_bytes (&b, 1, 1);
}

Jim Blandy's avatar
Jim Blandy committed
233
DEFUN ("string-to-char", Fstring_to_char, Sstring_to_char, 1, 1, 0,
234 235 236
       doc: /* Convert arg STRING to a character, the first character of that string.
A multibyte character is handled correctly.  */)
     (string)
237
     register Lisp_Object string;
Jim Blandy's avatar
Jim Blandy committed
238 239
{
  register Lisp_Object val;
240
  CHECK_STRING (string);
241
  if (SCHARS (string))
242 243
    {
      if (STRING_MULTIBYTE (string))
244
	XSETFASTINT (val, STRING_CHAR (SDATA (string)));
245
      else
246
	XSETFASTINT (val, SREF (string, 0));
247
    }
Jim Blandy's avatar
Jim Blandy committed
248
  else
249
    XSETFASTINT (val, 0);
Jim Blandy's avatar
Jim Blandy committed
250 251 252 253
  return val;
}

static Lisp_Object
254 255
buildmark (charpos, bytepos)
     int charpos, bytepos;
Jim Blandy's avatar
Jim Blandy committed
256 257 258
{
  register Lisp_Object mark;
  mark = Fmake_marker ();
259
  set_marker_both (mark, Qnil, charpos, bytepos);
Jim Blandy's avatar
Jim Blandy committed
260 261 262 263
  return mark;
}

DEFUN ("point", Fpoint, Spoint, 0, 0, 0,
264 265 266
       doc: /* Return value of point, as an integer.
Beginning of buffer is position (point-min).  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
267 268
{
  Lisp_Object temp;
269
  XSETFASTINT (temp, PT);
Jim Blandy's avatar
Jim Blandy committed
270 271 272 273
  return temp;
}

DEFUN ("point-marker", Fpoint_marker, Spoint_marker, 0, 0, 0,
274 275
       doc: /* Return value of point, as a marker object.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
276
{
277
  return buildmark (PT, PT_BYTE);
Jim Blandy's avatar
Jim Blandy committed
278 279 280 281 282 283 284 285 286 287 288 289 290 291 292
}

int
clip_to_bounds (lower, num, upper)
     int lower, num, upper;
{
  if (num < lower)
    return lower;
  else if (num > upper)
    return upper;
  else
    return num;
}

DEFUN ("goto-char", Fgoto_char, Sgoto_char, 1, 1, "NGoto char: ",
293
       doc: /* Set point to POSITION, a number or marker.
Eli Zaretskii's avatar
Eli Zaretskii committed
294 295 296
Beginning of buffer is position (point-min), end is (point-max).

The return value is POSITION.  */)
297
     (position)
298
     register Lisp_Object position;
Jim Blandy's avatar
Jim Blandy committed
299
{
Karl Heuer's avatar
Karl Heuer committed
300 301
  int pos;

302 303
  if (MARKERP (position)
      && current_buffer == XMARKER (position)->buffer)
304 305 306 307 308 309 310 311 312 313 314 315
    {
      pos = marker_position (position);
      if (pos < BEGV)
	SET_PT_BOTH (BEGV, BEGV_BYTE);
      else if (pos > ZV)
	SET_PT_BOTH (ZV, ZV_BYTE);
      else
	SET_PT_BOTH (pos, marker_byte_position (position));

      return position;
    }

316
  CHECK_NUMBER_COERCE_MARKER (position);
Jim Blandy's avatar
Jim Blandy committed
317

Karl Heuer's avatar
Karl Heuer committed
318 319
  pos = clip_to_bounds (BEGV, XINT (position), ZV);
  SET_PT (pos);
320
  return position;
Jim Blandy's avatar
Jim Blandy committed
321 322
}

323 324 325 326 327

/* Return the start or end position of the region.
   BEGINNINGP non-zero means return the start.
   If there is no region active, signal an error. */

Jim Blandy's avatar
Jim Blandy committed
328 329 330 331
static Lisp_Object
region_limit (beginningp)
     int beginningp;
{
332
  extern Lisp_Object Vmark_even_if_inactive; /* Defined in callint.c. */
333
  Lisp_Object m;
334

335 336
  if (!NILP (Vtransient_mark_mode)
      && NILP (Vmark_even_if_inactive)
337
      && NILP (current_buffer->mark_active))
338
    xsignal0 (Qmark_inactive);
339

Jim Blandy's avatar
Jim Blandy committed
340
  m = Fmarker_position (current_buffer->mark);
341
  if (NILP (m))
342
    error ("The mark is not set now, so there is no region");
343

Kenichi Handa's avatar
Kenichi Handa committed
344
  if ((PT < XFASTINT (m)) == (beginningp != 0))
345 346
    m = make_number (PT);
  return m;
Jim Blandy's avatar
Jim Blandy committed
347 348 349
}

DEFUN ("region-beginning", Fregion_beginning, Sregion_beginning, 0, 0, 0,
350 351
       doc: /* Return position of beginning of region, as an integer.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
352
{
353
  return region_limit (1);
Jim Blandy's avatar
Jim Blandy committed
354 355 356
}

DEFUN ("region-end", Fregion_end, Sregion_end, 0, 0, 0,
357 358
       doc: /* Return position of end of region, as an integer.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
359
{
360
  return region_limit (0);
Jim Blandy's avatar
Jim Blandy committed
361 362 363
}

DEFUN ("mark-marker", Fmark_marker, Smark_marker, 0, 0, 0,
364
       doc: /* Return this buffer's mark, as a marker object.
Pavel Janík's avatar
Pavel Janík committed
365
Watch out!  Moving this marker changes the mark position.
366 367
If you set the marker not to point anywhere, the buffer will have no mark.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
368 369 370
{
  return current_buffer->mark;
}
371 372


373 374 375 376 377 378 379 380 381 382
/* Find all the overlays in the current buffer that touch position POS.
   Return the number found, and store them in a vector in VEC
   of length LEN.  */

static int
overlays_around (pos, vec, len)
     int pos;
     Lisp_Object *vec;
     int len;
{
383 384
  Lisp_Object overlay, start, end;
  struct Lisp_Overlay *tail;
385 386 387
  int startpos, endpos;
  int idx = 0;

388
  for (tail = current_buffer->overlays_before; tail; tail = tail->next)
389
    {
390
      XSETMISC (overlay, tail);
391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406

      end = OVERLAY_END (overlay);
      endpos = OVERLAY_POSITION (end);
      if (endpos < pos)
	  break;
      start = OVERLAY_START (overlay);
      startpos = OVERLAY_POSITION (start);
      if (startpos <= pos)
	{
	  if (idx < len)
	    vec[idx] = overlay;
	  /* Keep counting overlays even if we can't return them all.  */
	  idx++;
	}
    }

407
  for (tail = current_buffer->overlays_after; tail; tail = tail->next)
408
    {
409
      XSETMISC (overlay, tail);
410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435

      start = OVERLAY_START (overlay);
      startpos = OVERLAY_POSITION (start);
      if (pos < startpos)
	break;
      end = OVERLAY_END (overlay);
      endpos = OVERLAY_POSITION (end);
      if (pos <= endpos)
	{
	  if (idx < len)
	    vec[idx] = overlay;
	  idx++;
	}
    }

  return idx;
}

/* Return the value of property PROP, in OBJECT at POSITION.
   It's the value of PROP that a char inserted at POSITION would get.
   OBJECT is optional and defaults to the current buffer.
   If OBJECT is a buffer, then overlay properties are considered as well as
   text properties.
   If OBJECT is a window, then that window's buffer is used, but
   window-specific overlays are considered only if they are associated
   with OBJECT. */
436
Lisp_Object
437 438 439 440 441 442 443 444
get_pos_property (position, prop, object)
     Lisp_Object position, object;
     register Lisp_Object prop;
{
  CHECK_NUMBER_COERCE_MARKER (position);

  if (NILP (object))
    XSETBUFFER (object, current_buffer);
445 446 447 448 449 450 451 452 453
  else if (WINDOWP (object))
    object = XWINDOW (object)->buffer;

  if (!BUFFERP (object))
    /* pos-property only makes sense in buffers right now, since strings
       have no overlays and no notion of insertion for which stickiness
       could be obeyed.  */
    return Fget_text_property (position, prop, object);
  else
454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497
    {
      int posn = XINT (position);
      int noverlays;
      Lisp_Object *overlay_vec, tem;
      struct buffer *obuf = current_buffer;

      set_buffer_temp (XBUFFER (object));

      /* First try with room for 40 overlays.  */
      noverlays = 40;
      overlay_vec = (Lisp_Object *) alloca (noverlays * sizeof (Lisp_Object));
      noverlays = overlays_around (posn, overlay_vec, noverlays);

      /* If there are more than 40,
	 make enough space for all, and try again.  */
      if (noverlays > 40)
	{
	  overlay_vec = (Lisp_Object *) alloca (noverlays * sizeof (Lisp_Object));
	  noverlays = overlays_around (posn, overlay_vec, noverlays);
	}
      noverlays = sort_overlays (overlay_vec, noverlays, NULL);

      set_buffer_temp (obuf);

      /* Now check the overlays in order of decreasing priority.  */
      while (--noverlays >= 0)
	{
	  Lisp_Object ol = overlay_vec[noverlays];
	  tem = Foverlay_get (ol, prop);
	  if (!NILP (tem))
	    {
	      /* Check the overlay is indeed active at point.  */
	      Lisp_Object start = OVERLAY_START (ol), finish = OVERLAY_END (ol);
	      if ((OVERLAY_POSITION (start) == posn
		   && XMARKER (start)->insertion_type == 1)
		  || (OVERLAY_POSITION (finish) == posn
		      && XMARKER (finish)->insertion_type == 0))
		; /* The overlay will not cover a char inserted at point.  */
	      else
		{
		  return tem;
		}
	    }
	}
498

499
      { /* Now check the text properties.  */
500 501 502 503 504 505 506 507 508 509
	int stickiness = text_property_stickiness (prop, position, object);
	if (stickiness > 0)
	  return Fget_text_property (position, prop, object);
	else if (stickiness < 0
		 && XINT (position) > BUF_BEGV (XBUFFER (object)))
	  return Fget_text_property (make_number (XINT (position) - 1),
				     prop, object);
	else
	  return Qnil;
      }
510 511 512
    }
}

513
/* Find the field surrounding POS in *BEG and *END.  If POS is nil,
Lars Hansen's avatar
Lars Hansen committed
514
   the value of point is used instead.  If BEG or END is null,
515
   means don't store the beginning or end of the field.
516

517 518 519
   BEG_LIMIT and END_LIMIT serve to limit the ranged of the returned
   results; they do not effect boundary behavior.

520
   If MERGE_AT_BOUNDARY is nonzero, then if POS is at the very first
521 522 523 524 525 526 527 528
   position of a field, then the beginning of the previous field is
   returned instead of the beginning of POS's field (since the end of a
   field is actually also the beginning of the next input field, this
   behavior is sometimes useful).  Additionally in the MERGE_AT_BOUNDARY
   true case, if two fields are separated by a field with the special
   value `boundary', and POS lies within it, then the two separated
   fields are considered to be adjacent, and POS between them, when
   finding the beginning and ending of the "merged" field.
529 530 531 532

   Either BEG or END may be 0, in which case the corresponding value
   is not stored.  */

533
static void
534
find_field (pos, merge_at_boundary, beg_limit, beg, end_limit, end)
535 536
     Lisp_Object pos;
     Lisp_Object merge_at_boundary;
537
     Lisp_Object beg_limit, end_limit;
538 539
     int *beg, *end;
{
540 541
  /* Fields right before and after the point.  */
  Lisp_Object before_field, after_field;
542 543 544 545
  /* 1 if POS counts as the start of a field.  */
  int at_field_start = 0;
  /* 1 if POS counts as the end of a field.  */
  int at_field_end = 0;
546

547 548 549
  if (NILP (pos))
    XSETFASTINT (pos, PT);
  else
550
    CHECK_NUMBER_COERCE_MARKER (pos);
551

552
  after_field
553
    = get_char_property_and_overlay (pos, Qfield, Qnil, NULL);
554 555
  before_field
    = (XFASTINT (pos) > BEGV
Miles Bader's avatar
Miles Bader committed
556
       ? get_char_property_and_overlay (make_number (XINT (pos) - 1),
557
					Qfield, Qnil, NULL)
558 559 560
       /* Using nil here would be a more obvious choice, but it would
          fail when the buffer starts with a non-sticky field.  */
       : after_field);
561 562 563 564 565 566 567

  /* See if we need to handle the case where MERGE_AT_BOUNDARY is nil
     and POS is at beginning of a field, which can also be interpreted
     as the end of the previous field.  Note that the case where if
     MERGE_AT_BOUNDARY is non-nil (see function comment) is actually the
     more natural one; then we avoid treating the beginning of a field
     specially.  */
568
  if (NILP (merge_at_boundary))
569
    {
570 571
      Lisp_Object field = get_pos_property (pos, Qfield, Qnil);
      if (!EQ (field, after_field))
572
	at_field_end = 1;
573 574
      if (!EQ (field, before_field))
	at_field_start = 1;
575 576 577 578 579 580
      if (NILP (field) && at_field_start && at_field_end)
	/* If an inserted char would have a nil field while the surrounding
	   text is non-nil, we're probably not looking at a
	   zero-length field, but instead at a non-nil field that's
	   not intended for editing (such as comint's prompts).  */
	at_field_end = at_field_start = 0;
581 582
    }

583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604
  /* Note about special `boundary' fields:

     Consider the case where the point (`.') is between the fields `x' and `y':

	xxxx.yyyy

     In this situation, if merge_at_boundary is true, we consider the
     `x' and `y' fields as forming one big merged field, and so the end
     of the field is the end of `y'.

     However, if `x' and `y' are separated by a special `boundary' field
     (a field with a `field' char-property of 'boundary), then we ignore
     this special field when merging adjacent fields.  Here's the same
     situation, but with a `boundary' field between the `x' and `y' fields:

	xxx.BBBByyyy

     Here, if point is at the end of `x', the beginning of `y', or
     anywhere in-between (within the `boundary' field), we merge all
     three fields and consider the beginning as being the beginning of
     the `x' field, and the end as being the end of the `y' field.  */

605
  if (beg)
606 607 608 609 610 611 612 613
    {
      if (at_field_start)
	/* POS is at the edge of a field, and we should consider it as
	   the beginning of the following field.  */
	*beg = XFASTINT (pos);
      else
	/* Find the previous field boundary.  */
	{
614
	  Lisp_Object p = pos;
615 616
	  if (!NILP (merge_at_boundary) && EQ (before_field, Qboundary))
	    /* Skip a `boundary' field.  */
617
	    p = Fprevious_single_char_property_change (p, Qfield, Qnil,
618
						       beg_limit);
619 620 621 622

	  p = Fprevious_single_char_property_change (p, Qfield, Qnil,
						     beg_limit);
	  *beg = NILP (p) ? BEGV : XFASTINT (p);
623 624
	}
    }
625 626

  if (end)
627 628 629 630 631 632 633 634 635 636
    {
      if (at_field_end)
	/* POS is at the edge of a field, and we should consider it as
	   the end of the previous field.  */
	*end = XFASTINT (pos);
      else
	/* Find the next field boundary.  */
	{
	  if (!NILP (merge_at_boundary) && EQ (after_field, Qboundary))
	    /* Skip a `boundary' field.  */
637 638
	    pos = Fnext_single_char_property_change (pos, Qfield, Qnil,
						     end_limit);
639

640 641
	  pos = Fnext_single_char_property_change (pos, Qfield, Qnil,
						   end_limit);
642 643 644
	  *end = NILP (pos) ? ZV : XFASTINT (pos);
	}
    }
645
}
646

647

648
DEFUN ("delete-field", Fdelete_field, Sdelete_field, 0, 1, 0,
649
       doc: /* Delete the field surrounding POS.
Pavel Janík's avatar
Pavel Janík committed
650
A field is a region of text with the same `field' property.
Thien-Thi Nguyen's avatar
Thien-Thi Nguyen committed
651
If POS is nil, the value of point is used for POS.  */)
652
     (pos)
653 654 655
     Lisp_Object pos;
{
  int beg, end;
656
  find_field (pos, Qnil, Qnil, &beg, Qnil, &end);
657 658
  if (beg != end)
    del_range (beg, end);
659
  return Qnil;
660 661 662
}

DEFUN ("field-string", Ffield_string, Sfield_string, 0, 1, 0,
663
       doc: /* Return the contents of the field surrounding POS as a string.
Pavel Janík's avatar
Pavel Janík committed
664
A field is a region of text with the same `field' property.
Thien-Thi Nguyen's avatar
Thien-Thi Nguyen committed
665
If POS is nil, the value of point is used for POS.  */)
666
     (pos)
667 668 669
     Lisp_Object pos;
{
  int beg, end;
670
  find_field (pos, Qnil, Qnil, &beg, Qnil, &end);
671 672 673 674
  return make_buffer_string (beg, end, 1);
}

DEFUN ("field-string-no-properties", Ffield_string_no_properties, Sfield_string_no_properties, 0, 1, 0,
675
       doc: /* Return the contents of the field around POS, without text properties.
Pavel Janík's avatar
Pavel Janík committed
676
A field is a region of text with the same `field' property.
Thien-Thi Nguyen's avatar
Thien-Thi Nguyen committed
677
If POS is nil, the value of point is used for POS.  */)
678
     (pos)
679 680 681
     Lisp_Object pos;
{
  int beg, end;
682
  find_field (pos, Qnil, Qnil, &beg, Qnil, &end);
683 684 685
  return make_buffer_string (beg, end, 0);
}

686
DEFUN ("field-beginning", Ffield_beginning, Sfield_beginning, 0, 3, 0,
687
       doc: /* Return the beginning of the field surrounding POS.
Pavel Janík's avatar
Pavel Janík committed
688 689 690
A field is a region of text with the same `field' property.
If POS is nil, the value of point is used for POS.
If ESCAPE-FROM-EDGE is non-nil and POS is at the beginning of its
691 692
field, then the beginning of the *previous* field is returned.
If LIMIT is non-nil, it is a buffer position; if the beginning of the field
Thien-Thi Nguyen's avatar
Thien-Thi Nguyen committed
693
is before LIMIT, then LIMIT will be returned instead.  */)
694 695
     (pos, escape_from_edge, limit)
     Lisp_Object pos, escape_from_edge, limit;
696 697
{
  int beg;
698
  find_field (pos, escape_from_edge, limit, &beg, Qnil, 0);
699 700 701
  return make_number (beg);
}

702
DEFUN ("field-end", Ffield_end, Sfield_end, 0, 3, 0,
703
       doc: /* Return the end of the field surrounding POS.
Pavel Janík's avatar
Pavel Janík committed
704 705 706
A field is a region of text with the same `field' property.
If POS is nil, the value of point is used for POS.
If ESCAPE-FROM-EDGE is non-nil and POS is at the end of its field,
707 708
then the end of the *following* field is returned.
If LIMIT is non-nil, it is a buffer position; if the end of the field
Thien-Thi Nguyen's avatar
Thien-Thi Nguyen committed
709
is after LIMIT, then LIMIT will be returned instead.  */)
710 711
     (pos, escape_from_edge, limit)
     Lisp_Object pos, escape_from_edge, limit;
712 713
{
  int end;
714
  find_field (pos, escape_from_edge, Qnil, 0, limit, &end);
715 716 717
  return make_number (end);
}

718
DEFUN ("constrain-to-field", Fconstrain_to_field, Sconstrain_to_field, 2, 5, 0,
719
       doc: /* Return the position closest to NEW-POS that is in the same field as OLD-POS.
Pavel Janík's avatar
Pavel Janík committed
720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743

A field is a region of text with the same `field' property.
If NEW-POS is nil, then the current point is used instead, and set to the
constrained position if that is different.

If OLD-POS is at the boundary of two fields, then the allowable
positions for NEW-POS depends on the value of the optional argument
ESCAPE-FROM-EDGE: If ESCAPE-FROM-EDGE is nil, then NEW-POS is
constrained to the field that has the same `field' char-property
as any new characters inserted at OLD-POS, whereas if ESCAPE-FROM-EDGE
is non-nil, NEW-POS is constrained to the union of the two adjacent
fields.  Additionally, if two fields are separated by another field with
the special value `boundary', then any point within this special field is
also considered to be `on the boundary'.

If the optional argument ONLY-IN-LINE is non-nil and constraining
NEW-POS would move it to a different line, NEW-POS is returned
unconstrained.  This useful for commands that move by line, like
\\[next-line] or \\[beginning-of-line], which should generally respect field boundaries
only in the case where they can still move to the right line.

If the optional argument INHIBIT-CAPTURE-PROPERTY is non-nil, and OLD-POS has
a non-nil property of that name, then any field boundaries are ignored.

744 745
Field boundaries are not noticed if `inhibit-field-text-motion' is non-nil.  */)
     (new_pos, old_pos, escape_from_edge, only_in_line, inhibit_capture_property)
746 747
     Lisp_Object new_pos, old_pos;
     Lisp_Object escape_from_edge, only_in_line, inhibit_capture_property;
748 749 750
{
  /* If non-zero, then the original point, before re-positioning.  */
  int orig_point = 0;
751 752
  int fwd;
  Lisp_Object prev_old, prev_new;
753

754 755 756 757 758 759 760
  if (NILP (new_pos))
    /* Use the current point, and afterwards, set it.  */
    {
      orig_point = PT;
      XSETFASTINT (new_pos, PT);
    }

761 762 763 764 765 766 767
  CHECK_NUMBER_COERCE_MARKER (new_pos);
  CHECK_NUMBER_COERCE_MARKER (old_pos);

  fwd = (XFASTINT (new_pos) > XFASTINT (old_pos));

  prev_old = make_number (XFASTINT (old_pos) - 1);
  prev_new = make_number (XFASTINT (new_pos) - 1);
768

769 770
  if (NILP (Vinhibit_field_text_motion)
      && !EQ (new_pos, old_pos)
771 772
      && (!NILP (Fget_char_property (new_pos, Qfield, Qnil))
          || !NILP (Fget_char_property (old_pos, Qfield, Qnil))
773 774 775 776 777
          /* To recognize field boundaries, we must also look at the
             previous positions; we could use `get_pos_property'
             instead, but in itself that would fail inside non-sticky
             fields (like comint prompts).  */
          || (XFASTINT (new_pos) > BEGV
778
              && !NILP (Fget_char_property (prev_new, Qfield, Qnil)))
779
          || (XFASTINT (old_pos) > BEGV
780
              && !NILP (Fget_char_property (prev_old, Qfield, Qnil))))
781
      && (NILP (inhibit_capture_property)
782 783 784 785 786
          /* Field boundaries are again a problem; but now we must
             decide the case exactly, so we need to call
             `get_pos_property' as well.  */
          || (NILP (get_pos_property (old_pos, inhibit_capture_property, Qnil))
              && (XFASTINT (old_pos) <= BEGV
787 788
                  || NILP (Fget_char_property (old_pos, inhibit_capture_property, Qnil))
                  || NILP (Fget_char_property (prev_old, inhibit_capture_property, Qnil))))))
789 790
    /* It is possible that NEW_POS is not within the same field as
       OLD_POS; try to move NEW_POS so that it is.  */
791
    {
792
      int shortage;
793 794 795
      Lisp_Object field_bound;

      if (fwd)
796
	field_bound = Ffield_end (old_pos, escape_from_edge, new_pos);
797
      else
798
	field_bound = Ffield_beginning (old_pos, escape_from_edge, new_pos);
799

800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816
      if (/* See if ESCAPE_FROM_EDGE caused FIELD_BOUND to jump to the
             other side of NEW_POS, which would mean that NEW_POS is
             already acceptable, and it's not necessary to constrain it
             to FIELD_BOUND.  */
	  ((XFASTINT (field_bound) < XFASTINT (new_pos)) ? fwd : !fwd)
	  /* NEW_POS should be constrained, but only if either
	     ONLY_IN_LINE is nil (in which case any constraint is OK),
	     or NEW_POS and FIELD_BOUND are on the same line (in which
	     case the constraint is OK even if ONLY_IN_LINE is non-nil). */
	  && (NILP (only_in_line)
	      /* This is the ONLY_IN_LINE case, check that NEW_POS and
		 FIELD_BOUND are on the same line by seeing whether
		 there's an intervening newline or not.  */
	      || (scan_buffer ('\n',
			       XFASTINT (new_pos), XFASTINT (field_bound),
			       fwd ? -1 : 1, &shortage, 1),
		  shortage != 0)))
817 818 819 820 821 822 823 824 825 826
	/* Constrain NEW_POS to FIELD_BOUND.  */
	new_pos = field_bound;

      if (orig_point && XFASTINT (new_pos) != orig_point)
	/* The NEW_POS argument was originally nil, so automatically set PT. */
	SET_PT (XFASTINT (new_pos));
    }

  return new_pos;
}
827

828

829 830
DEFUN ("line-beginning-position",
       Fline_beginning_position, Sline_beginning_position, 0, 1, 0,
831
       doc: /* Return the character position of the first character on the current line.
Pavel Janík's avatar
Pavel Janík committed
832 833
With argument N not nil or 1, move forward N - 1 lines first.
If scan reaches end of buffer, return that position.
834

835 836 837 838
This function constrains the returned position to the current field
unless that would be on a different line than the original,
unconstrained result.  If N is nil or 1, and a front-sticky field
starts at point, the scan stops as soon as it starts.  To ignore field
839
boundaries bind `inhibit-field-text-motion' to t.
Pavel Janík's avatar
Pavel Janík committed
840

841 842
This function does not move point.  */)
     (n)
843 844
     Lisp_Object n;
{
845
  int orig, orig_byte, end;
846 847
  int count = SPECPDL_INDEX ();
  specbind (Qinhibit_point_motion_hooks, Qt);
848 849 850 851

  if (NILP (n))
    XSETFASTINT (n, 1);
  else
852
    CHECK_NUMBER (n);
853 854

  orig = PT;
855
  orig_byte = PT_BYTE;
856 857
  Fforward_line (make_number (XINT (n) - 1));
  end = PT;
858

859
  SET_PT_BOTH (orig, orig_byte);
Jim Blandy's avatar
Jim Blandy committed
860

861 862
  unbind_to (count, Qnil);

863
  /* Return END constrained to the current input field.  */
864 865
  return Fconstrain_to_field (make_number (end), make_number (orig),
			      XINT (n) != 1 ? Qt : Qnil,
866
			      Qt, Qnil);
867 868
}

869
DEFUN ("line-end-position", Fline_end_position, Sline_end_position, 0, 1, 0,
870
       doc: /* Return the character position of the last character on the current line.
Pavel Janík's avatar
Pavel Janík committed
871 872
With argument N not nil or 1, move forward N - 1 lines first.
If scan reaches end of buffer, return that position.
873

874 875 876 877
This function constrains the returned position to the current field
unless that would be on a different line than the original,
unconstrained result.  If N is nil or 1, and a rear-sticky field ends
at point, the scan stops as soon as it starts.  To ignore field
878 879
boundaries bind `inhibit-field-text-motion' to t.

880 881
This function does not move point.  */)
     (n)
882 883
     Lisp_Object n;
{
884
  int end_pos;
885
  int orig = PT;
886

887 888 889
  if (NILP (n))
    XSETFASTINT (n, 1);
  else
890
    CHECK_NUMBER (n);
891

892 893 894
  end_pos = find_before_next_newline (orig, 0, XINT (n) - (XINT (n) <= 0));

  /* Return END_POS constrained to the current input field.  */
895
  return Fconstrain_to_field (make_number (end_pos), make_number (orig),
896
			      Qnil, Qt, Qnil);
897
}
898

899

Jim Blandy's avatar
Jim Blandy committed
900 901 902
Lisp_Object
save_excursion_save ()
{
903 904
  int visible = (XBUFFER (XWINDOW (selected_window)->buffer)
		 == current_buffer);
Jim Blandy's avatar
Jim Blandy committed
905 906

  return Fcons (Fpoint_marker (),
907
		Fcons (Fcopy_marker (current_buffer->mark, Qnil),
908
		       Fcons (visible ? Qt : Qnil,
909 910
			      Fcons (current_buffer->mark_active,
				     selected_window))));
Jim Blandy's avatar
Jim Blandy committed
911 912 913 914
}

Lisp_Object
save_excursion_restore (info)
915
     Lisp_Object info;
Jim Blandy's avatar
Jim Blandy committed
916
{
917 918
  Lisp_Object tem, tem1, omark, nmark;
  struct gcpro gcpro1, gcpro2, gcpro3;
919
  int visible_p;
Jim Blandy's avatar
Jim Blandy committed
920

921
  tem = Fmarker_buffer (XCAR (info));
Jim Blandy's avatar
Jim Blandy committed
922 923 924 925
  /* If buffer being returned to is now deleted, avoid error */
  /* Otherwise could get error here while unwinding to top level
     and crash */
  /* In that case, Fmarker_buffer returns nil now.  */
Jim Blandy's avatar
Jim Blandy committed
926
  if (NILP (tem))
Jim Blandy's avatar
Jim Blandy committed
927
    return Qnil;
928 929 930 931

  omark = nmark = Qnil;
  GCPRO3 (info, omark, nmark);

Jim Blandy's avatar
Jim Blandy committed
932
  Fset_buffer (tem);
933 934 935

  /* Point marker.  */
  tem = XCAR (info);
Jim Blandy's avatar
Jim Blandy committed
936
  Fgoto_char (tem);
937
  unchain_marker (XMARKER (tem));
938 939 940 941

  /* Mark marker.  */
  info = XCDR (info);
  tem = XCAR (info);
942
  omark = Fmarker_position (current_buffer->mark);
Jim Blandy's avatar
Jim Blandy committed
943
  Fset_marker (current_buffer->mark, tem, Fcurrent_buffer ());
944
  nmark = Fmarker_position (tem);
945
  unchain_marker (XMARKER (tem));
946 947 948 949

  /* visible */
  info = XCDR (info);
  visible_p = !NILP (XCAR (info));
950

951 952 953 954
#if 0 /* We used to make the current buffer visible in the selected window
	 if that was true previously.  That avoids some anomalies.
	 But it creates others, and it wasn't documented, and it is simpler
	 and cleaner never to alter the window/buffer connections.  */
955 956
  tem1 = Fcar (tem);
  if (!NILP (tem1)
957
      && current_buffer != XBUFFER (XWINDOW (selected_window)->buffer))
Jim Blandy's avatar
Jim Blandy committed
958
    Fswitch_to_buffer (Fcurrent_buffer (), Qnil);
959
#endif /* 0 */
960

961 962 963
  /* Mark active */
  info = XCDR (info);
  tem = XCAR (info);
964
  tem1 = current_buffer->mark_active;
965 966
  current_buffer->mark_active = tem;

967 968
  if (!NILP (Vrun_hooks))
    {
969 970
      /* If mark is active now, and either was not active
	 or was at a different place, run the activate hook.  */
971
      if (! NILP (current_buffer->mark_active))
972 973 974 975 976
	{
	  if (! EQ (omark, nmark))
	    call1 (Vrun_hooks, intern ("activate-mark-hook"));
	}
      /* If mark has ceased to be active, run deactivate hook.  */
977 978 979
      else if (! NILP (tem1))
	call1 (Vrun_hooks, intern ("deactivate-mark-hook"));
    }
980 981

  /* If buffer was visible in a window, and a different window was
982 983
     selected, and the old selected window is still showing this
     buffer, restore point in that window.  */
984 985 986
  tem = XCDR (info);
  if (visible_p
      && !EQ (tem, selected_window)
987 988 989 990 991
      && (tem1 = XWINDOW (tem)->buffer,
	  (/* Window is live...  */
	   BUFFERP (tem1)
	   /* ...and it shows the current buffer.  */
	   && XBUFFER (tem1) == current_buffer)))
992 993
    Fset_window_point (tem, make_number (PT));

994
  UNGCPRO;
Jim Blandy's avatar
Jim Blandy committed
995 996 997 998
  return Qnil;
}

DEFUN ("save-excursion", Fsave_excursion, Ssave_excursion, 0, UNEVALLED, 0,
999
       doc: /* Save point, mark, and current buffer; execute BODY; restore those things.
Pavel Janík's avatar
Pavel Janík committed
1000 1001 1002 1003 1004 1005 1006 1007
Executes BODY just like `progn'.
The values of point, mark and the current buffer are restored
even in case of abnormal exit (throw or error).
The state of activation of the mark is also restored.

This construct does not save `deactivate-mark', and therefore
functions that change the buffer will still cause deactivation
of the mark at the end of the command.  To prevent that, bind
1008 1009
`deactivate-mark' with `let'.

1010 1011 1012
If you only want to save the current buffer but not point nor mark,
then just use `save-current-buffer', or even `with-current-buffer'.

1013
usage: (save-excursion &rest BODY)  */)
1014
     (args)
Jim Blandy's avatar
Jim Blandy committed
1015 1016 1017
     Lisp_Object args;
{
  register Lisp_Object val;
Juanma Barranquero's avatar
Juanma Barranquero committed
1018
  int count = SPECPDL_INDEX ();
Jim Blandy's avatar
Jim Blandy committed
1019 1020

  record_unwind_protect (save_excursion_restore, save_excursion_save ());
1021 1022 1023 1024 1025 1026

  val = Fprogn (args);
  return unbind_to (count, val);
}

DEFUN ("save-current-buffer", Fsave_current_buffer, Ssave_current_buffer, 0, UNEVALLED, 0,
1027
       doc: /* Save the current buffer; execute BODY; restore the current buffer.
1028 1029
Executes BODY just like `progn'.
usage: (save-current-buffer &rest BODY)  */)
1030
     (args)
1031 1032
     Lisp_Object args;
{
1033
  Lisp_Object val;
Juanma Barranquero's avatar
Juanma Barranquero committed
1034
  int count = SPECPDL_INDEX ();
1035

1036
  record_unwind_protect (set_buffer_if_live, Fcurrent_buffer ());
1037

Jim Blandy's avatar
Jim Blandy committed
1038 1039 1040 1041
  val = Fprogn (args);
  return unbind_to (count, val);
}

1042
DEFUN ("buffer-size", Fbufsize, Sbufsize, 0, 1, 0,
1043 1044 1045
       doc: /* Return the number of characters in the current buffer.
If BUFFER, return the number of characters in that buffer instead.  */)
     (buffer)
1046
     Lisp_Object buffer;
Jim Blandy's avatar
Jim Blandy committed
1047
{
1048 1049
  if (NILP (buffer))
    return make_number (Z - BEG);
1050 1051
  else
    {
1052
      CHECK_BUFFER (buffer);
1053 1054 1055
      return make_number (BUF_Z (XBUFFER (buffer))
			  - BUF_BEG (XBUFFER (buffer)));
    }
Jim Blandy's avatar
Jim Blandy committed
1056 1057 1058
}

DEFUN ("point-min", Fpoint_min, Spoint_min, 0, 0, 0,
1059 1060 1061
       doc: /* Return the minimum permissible value of point in the current buffer.
This is 1, unless narrowing (a buffer restriction) is in effect.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
1062 1063
{
  Lisp_Object temp;
1064
  XSETFASTINT (temp, BEGV);
Jim Blandy's avatar
Jim Blandy committed
1065 1066 1067 1068
  return temp;
}

DEFUN ("point-min-marker", Fpoint_min_marker, Spoint_min_marker, 0, 0, 0,
1069 1070 1071
       doc: /* Return a marker to the minimum permissible value of point in this buffer.
This is the beginning, unless narrowing (a buffer restriction) is in effect.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
1072
{
1073
  return buildmark (BEGV, BEGV_BYTE);
Jim Blandy's avatar
Jim Blandy committed
1074 1075 1076
}

DEFUN ("point-max", Fpoint_max, Spoint_max, 0, 0, 0,
1077
       doc: /* Return the maximum permissible value of point in the current buffer.
Pavel Janík's avatar
Pavel Janík committed
1078
This is (1+ (buffer-size)), unless narrowing (a buffer restriction)
1079 1080
is in effect, in which case it is less.  */)
     ()
Jim Blandy's avatar
Jim Blandy committed
1081 1082
{
  Lisp_Object temp;
1083
  XSETFASTINT (temp, ZV);
Jim Blandy's avatar
Jim Blandy committed
1084 1085 1086 1087
  return temp;
}

DEFUN ("point-max-marker", Fpoint_max_marker, Spoint_max_marker, 0, 0, 0,