textprop.c 29.2 KB
Newer Older
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1
/* Interface code for dealing with text properties.
2
   Copyright (C) 1993 Free Software Foundation, Inc.
Joseph Arceneaux's avatar
Joseph Arceneaux committed
3 4 5 6 7

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
Jim Blandy's avatar
Jim Blandy committed
8
the Free Software Foundation; either version 2, or (at your option)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
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
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "config.h"
#include "lisp.h"
#include "intervals.h"
#include "buffer.h"


/* NOTES:  previous- and next- property change will have to skip
  zero-length intervals if they are implemented.  This could be done
  inside next_interval and previous_interval.

Joseph Arceneaux's avatar
Joseph Arceneaux committed
30 31
  set_properties needs to deal with the interval property cache.

Joseph Arceneaux's avatar
Joseph Arceneaux committed
32
  It is assumed that for any interval plist, a property appears
33
  only once on the list.  Although some code i.e., remove_properties,
Joseph Arceneaux's avatar
Joseph Arceneaux committed
34
  handles the more general case, the uniqueness of properties is
35
  necessary for the system to remain consistent.  This requirement
Joseph Arceneaux's avatar
Joseph Arceneaux committed
36 37
  is enforced by the subrs installing properties onto the intervals. */

38 39
/* The rest of the file is within this conditional */
#ifdef USE_TEXT_PROPERTIES
Joseph Arceneaux's avatar
Joseph Arceneaux committed
40 41 42 43 44 45

/* Types of hooks. */
Lisp_Object Qmouse_left;
Lisp_Object Qmouse_entered;
Lisp_Object Qpoint_left;
Lisp_Object Qpoint_entered;
46
Lisp_Object Qmodification_hooks;
47 48
Lisp_Object Qcategory;
Lisp_Object Qlocal_map;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
49 50 51 52

/* Visual properties text (including strings) may have. */
Lisp_Object Qforeground, Qbackground, Qfont, Qunderline, Qstipple;
Lisp_Object Qinvisible, Qread_only;
53 54 55 56 57 58

/* If o1 is a cons whose cdr is a cons, return non-zero and set o2 to
   the o1's cdr.  Otherwise, return zero.  This is handy for
   traversing plists.  */
#define PLIST_ELT_P(o1, o2) (CONSP (o1) && CONSP ((o2) = XCONS (o1)->cdr))

Joseph Arceneaux's avatar
Joseph Arceneaux committed
59

Joseph Arceneaux's avatar
Joseph Arceneaux committed
60 61 62 63 64 65
/* Extract the interval at the position pointed to by BEGIN from
   OBJECT, a string or buffer.  Additionally, check that the positions
   pointed to by BEGIN and END are within the bounds of OBJECT, and
   reverse them if *BEGIN is greater than *END.  The objects pointed
   to by BEGIN and END may be integers or markers; if the latter, they
   are coerced to integers.
Joseph Arceneaux's avatar
Joseph Arceneaux committed
66

67 68 69
   When OBJECT is a string, we increment *BEGIN and *END
   to make them origin-one.

Joseph Arceneaux's avatar
Joseph Arceneaux committed
70 71 72 73 74 75 76 77 78
   Note that buffer points don't correspond to interval indices.
   For example, point-max is 1 greater than the index of the last
   character.  This difference is handled in the caller, which uses
   the validated points to determine a length, and operates on that.
   Exceptions are Ftext_properties_at, Fnext_property_change, and
   Fprevious_property_change which call this function with BEGIN == END.
   Handle this case specially.

   If FORCE is soft (0), it's OK to return NULL_INTERVAL.  Otherwise,
Joseph Arceneaux's avatar
Joseph Arceneaux committed
79 80
   create an interval tree for OBJECT if one doesn't exist, provided
   the object actually contains text.  In the current design, if there
81
   is no text, there can be no text properties.  */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
82 83 84 85 86 87 88 89 90 91

#define soft 0
#define hard 1

static INTERVAL
validate_interval_range (object, begin, end, force)
     Lisp_Object object, *begin, *end;
     int force;
{
  register INTERVAL i;
92 93
  int searchpos;

Joseph Arceneaux's avatar
Joseph Arceneaux committed
94 95 96 97 98 99 100 101 102 103 104
  CHECK_STRING_OR_BUFFER (object, 0);
  CHECK_NUMBER_COERCE_MARKER (*begin, 0);
  CHECK_NUMBER_COERCE_MARKER (*end, 0);

  /* If we are asked for a point, but from a subr which operates
     on a range, then return nothing. */
  if (*begin == *end && begin != end)
    return NULL_INTERVAL;

  if (XINT (*begin) > XINT (*end))
    {
105 106
      Lisp_Object n;
      n = *begin;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
107
      *begin = *end;
108
      *end = n;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
109 110 111 112 113 114 115 116 117 118 119
    }

  if (XTYPE (object) == Lisp_Buffer)
    {
      register struct buffer *b = XBUFFER (object);

      if (!(BUF_BEGV (b) <= XINT (*begin) && XINT (*begin) <= XINT (*end)
	    && XINT (*end) <= BUF_ZV (b)))
	args_out_of_range (*begin, *end);
      i = b->intervals;

120 121 122 123 124 125 126 127
      /* If there's no text, there are no properties. */
      if (BUF_BEGV (b) == BUF_ZV (b))
	return NULL_INTERVAL;

      searchpos = XINT (*begin);
      if (searchpos == BUF_Z (b))
	searchpos--;
#if 0
Joseph Arceneaux's avatar
Joseph Arceneaux committed
128 129 130 131
      /* Special case for point-max:  return the interval for the
         last character. */
      if (*begin == *end && *begin == BUF_Z (b))
	*begin -= 1;
132
#endif
Joseph Arceneaux's avatar
Joseph Arceneaux committed
133 134 135 136 137
    }
  else
    {
      register struct Lisp_String *s = XSTRING (object);

138
      if (! (0 <= XINT (*begin) && XINT (*begin) <= XINT (*end)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
139 140
	     && XINT (*end) <= s->size))
	args_out_of_range (*begin, *end);
141 142 143 144
      /* User-level Positions in strings start with 0,
	 but the interval code always wants positions starting with 1.  */
      XFASTINT (*begin) += 1;
      XFASTINT (*end) += 1;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
145
      i = s->intervals;
146 147 148 149 150 151 152

      if (s->size == 0)
	return NULL_INTERVAL;

      searchpos = XINT (*begin);
      if (searchpos > s->size)
	searchpos--;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
153 154 155 156 157
    }

  if (NULL_INTERVAL_P (i))
    return (force ? create_root_interval (object) : i);
    
158
  return find_interval (i, searchpos);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246
}

/* Validate LIST as a property list.  If LIST is not a list, then
   make one consisting of (LIST nil).  Otherwise, verify that LIST
   is even numbered and thus suitable as a plist. */

static Lisp_Object
validate_plist (list)
{
  if (NILP (list))
    return Qnil;

  if (CONSP (list))
    {
      register int i;
      register Lisp_Object tail;
      for (i = 0, tail = list; !NILP (tail); i++)
	tail = Fcdr (tail);
      if (i & 1)
	error ("Odd length text property list");
      return list;
    }

  return Fcons (list, Fcons (Qnil, Qnil));
}

/* Return nonzero if interval I has all the properties,
   with the same values, of list PLIST. */

static int
interval_has_all_properties (plist, i)
     Lisp_Object plist;
     INTERVAL i;
{
  register Lisp_Object tail1, tail2, sym1, sym2;
  register int found;

  /* Go through each element of PLIST. */
  for (tail1 = plist; ! NILP (tail1); tail1 = Fcdr (Fcdr (tail1)))
    {
      sym1 = Fcar (tail1);
      found = 0;

      /* Go through I's plist, looking for sym1 */
      for (tail2 = i->plist; ! NILP (tail2); tail2 = Fcdr (Fcdr (tail2)))
	if (EQ (sym1, Fcar (tail2)))
	  {
	    /* Found the same property on both lists.  If the
	       values are unequal, return zero. */
	    if (! EQ (Fequal (Fcar (Fcdr (tail1)), Fcar (Fcdr (tail2))),
		      Qt))
	      return 0;

	    /* Property has same value on both lists;  go to next one. */
	    found = 1;
	    break;
	  }

      if (! found)
	return 0;
    }

  return 1;
}

/* Return nonzero if the plist of interval I has any of the
   properties of PLIST, regardless of their values. */

static INLINE int
interval_has_some_properties (plist, i)
     Lisp_Object plist;
     INTERVAL i;
{
  register Lisp_Object tail1, tail2, sym;

  /* Go through each element of PLIST. */
  for (tail1 = plist; ! NILP (tail1); tail1 = Fcdr (Fcdr (tail1)))
    {
      sym = Fcar (tail1);

      /* Go through i's plist, looking for tail1 */
      for (tail2 = i->plist; ! NILP (tail2); tail2 = Fcdr (Fcdr (tail2)))
	if (EQ (sym, Fcar (tail2)))
	  return 1;
    }

  return 0;
}
247

248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265
/* Changing the plists of individual intervals.  */

/* Return the value of PROP in property-list PLIST, or Qunbound if it
   has none.  */
static int
property_value (plist, prop)
{
  Lisp_Object value;

  while (PLIST_ELT_P (plist, value))
    if (EQ (XCONS (plist)->car, prop))
      return XCONS (value)->car;
    else
      plist = XCONS (value)->cdr;

  return Qunbound;
}

266 267 268 269 270 271 272 273 274
/* Set the properties of INTERVAL to PROPERTIES,
   and record undo info for the previous values.
   OBJECT is the string or buffer that INTERVAL belongs to.  */

static void
set_properties (properties, interval, object)
     Lisp_Object properties, object;
     INTERVAL interval;
{
275
  Lisp_Object sym, value;
276

277
  if (BUFFERP (object))
278
    {
279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298
      /* For each property in the old plist which is missing from PROPERTIES,
	 or has a different value in PROPERTIES, make an undo record.  */
      for (sym = interval->plist;
	   PLIST_ELT_P (sym, value);
	   sym = XCONS (value)->cdr)
	if (! EQ (property_value (properties, XCONS (sym)->car),
		  XCONS (value)->car))
	  record_property_change (interval->position, LENGTH (interval),
				  XCONS (sym)->car, XCONS (value)->car,
				  object);

      /* For each new property that has no value at all in the old plist,
	 make an undo record binding it to nil, so it will be removed.  */
      for (sym = properties;
	   PLIST_ELT_P (sym, value);
	   sym = XCONS (value)->cdr)
	if (EQ (property_value (interval->plist, XCONS (sym)->car), Qunbound))
	  record_property_change (interval->position, LENGTH (interval),
				  XCONS (sym)->car, Qnil,
				  object);
299 300 301 302 303
    }

  /* Store new properties.  */
  interval->plist = Fcopy_sequence (properties);
}
Joseph Arceneaux's avatar
Joseph Arceneaux committed
304 305 306 307 308

/* Add the properties of PLIST to the interval I, or set
   the value of I's property to the value of the property on PLIST
   if they are different.

309 310
   OBJECT should be the string or buffer the interval is in.

Joseph Arceneaux's avatar
Joseph Arceneaux committed
311 312 313
   Return nonzero if this changes I (i.e., if any members of PLIST
   are actually added to I's plist) */

314 315
static int
add_properties (plist, i, object)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
316 317
     Lisp_Object plist;
     INTERVAL i;
318
     Lisp_Object object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341
{
  register Lisp_Object tail1, tail2, sym1, val1;
  register int changed = 0;
  register int found;

  /* Go through each element of PLIST. */
  for (tail1 = plist; ! NILP (tail1); tail1 = Fcdr (Fcdr (tail1)))
    {
      sym1 = Fcar (tail1);
      val1 = Fcar (Fcdr (tail1));
      found = 0;

      /* Go through I's plist, looking for sym1 */
      for (tail2 = i->plist; ! NILP (tail2); tail2 = Fcdr (Fcdr (tail2)))
	if (EQ (sym1, Fcar (tail2)))
	  {
	    register Lisp_Object this_cdr = Fcdr (tail2);

	    /* Found the property.  Now check its value. */
	    found = 1;

	    /* The properties have the same value on both lists.
	       Continue to the next property. */
342
	    if (!NILP (Fequal (val1, Fcar (this_cdr))))
Joseph Arceneaux's avatar
Joseph Arceneaux committed
343 344
	      break;

345 346 347 348 349
	    /* Record this change in the buffer, for undo purposes.  */
	    if (XTYPE (object) == Lisp_Buffer)
	      {
		record_property_change (i->position, LENGTH (i),
					sym1, Fcar (this_cdr), object);
350 351
		modify_region (XBUFFER (object),
			       make_number (i->position),
352 353 354
			       make_number (i->position + LENGTH (i)));
	      }

Joseph Arceneaux's avatar
Joseph Arceneaux committed
355 356 357 358 359 360 361 362
	    /* I's property has a different value -- change it */
	    Fsetcar (this_cdr, val1);
	    changed++;
	    break;
	  }

      if (! found)
	{
363 364 365 366 367
	  /* Record this change in the buffer, for undo purposes.  */
	  if (XTYPE (object) == Lisp_Buffer)
	    {
	      record_property_change (i->position, LENGTH (i),
				      sym1, Qnil, object);
368 369
	      modify_region (XBUFFER (object),
			     make_number (i->position),
370 371
			     make_number (i->position + LENGTH (i)));
	    }
Joseph Arceneaux's avatar
Joseph Arceneaux committed
372 373 374 375 376 377 378 379 380
	  i->plist = Fcons (sym1, Fcons (val1, i->plist));
	  changed++;
	}
    }

  return changed;
}

/* For any members of PLIST which are properties of I, remove them
381 382
   from I's plist.
   OBJECT is the string or buffer containing I.  */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
383

384 385
static int
remove_properties (plist, i, object)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
386 387
     Lisp_Object plist;
     INTERVAL i;
388
     Lisp_Object object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
389 390 391 392 393 394 395 396 397 398 399 400 401
{
  register Lisp_Object tail1, tail2, sym;
  register Lisp_Object current_plist = i->plist;
  register int changed = 0;

  /* Go through each element of plist. */
  for (tail1 = plist; ! NILP (tail1); tail1 = Fcdr (Fcdr (tail1)))
    {
      sym = Fcar (tail1);

      /* First, remove the symbol if its at the head of the list */
      while (! NILP (current_plist) && EQ (sym, Fcar (current_plist)))
	{
402 403 404 405 406
	  if (XTYPE (object) == Lisp_Buffer)
	    {
	      record_property_change (i->position, LENGTH (i),
				      sym, Fcar (Fcdr (current_plist)),
				      object);
407 408
	      modify_region (XBUFFER (object),
			     make_number (i->position),
409 410 411
			     make_number (i->position + LENGTH (i)));
	    }

Joseph Arceneaux's avatar
Joseph Arceneaux committed
412 413 414 415 416 417 418 419 420 421 422
	  current_plist = Fcdr (Fcdr (current_plist));
	  changed++;
	}

      /* Go through i's plist, looking for sym */
      tail2 = current_plist;
      while (! NILP (tail2))
	{
	  register Lisp_Object this = Fcdr (Fcdr (tail2));
	  if (EQ (sym, Fcar (this)))
	    {
423 424 425 426
	      if (XTYPE (object) == Lisp_Buffer)
		{
		  record_property_change (i->position, LENGTH (i),
					  sym, Fcar (Fcdr (this)), object);
427 428
		  modify_region (XBUFFER (object),
				 make_number (i->position),
429 430 431
				 make_number (i->position + LENGTH (i)));
		}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
432 433 434 435 436 437 438 439 440 441 442 443
	      Fsetcdr (Fcdr (tail2), Fcdr (Fcdr (this)));
	      changed++;
	    }
	  tail2 = this;
	}
    }

  if (changed)
    i->plist = current_plist;
  return changed;
}

444
#if 0
Joseph Arceneaux's avatar
Joseph Arceneaux committed
445 446 447 448 449 450 451 452 453 454 455 456 457
/* Remove all properties from interval I.  Return non-zero
   if this changes the interval. */

static INLINE int
erase_properties (i)
     INTERVAL i;
{
  if (NILP (i->plist))
    return 0;

  i->plist = Qnil;
  return 1;
}
458
#endif
Joseph Arceneaux's avatar
Joseph Arceneaux committed
459 460 461 462 463

DEFUN ("text-properties-at", Ftext_properties_at,
       Stext_properties_at, 1, 2, 0,
  "Return the list of properties held by the character at POSITION\n\
in optional argument OBJECT, a string or buffer.  If nil, OBJECT\n\
464 465
defaults to the current buffer.\n\
If POSITION is at the end of OBJECT, the value is nil.")
Joseph Arceneaux's avatar
Joseph Arceneaux committed
466 467 468 469 470 471 472 473 474 475 476
  (pos, object)
     Lisp_Object pos, object;
{
  register INTERVAL i;

  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

  i = validate_interval_range (object, &pos, &pos, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;
477 478 479 480 481 482
  /* If POS is at the end of the interval,
     it means it's the end of OBJECT.
     There are no properties at the very end,
     since no character follows.  */
  if (XINT (pos) == LENGTH (i) + i->position)
    return Qnil;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
483 484 485 486

  return i->plist;
}

487
DEFUN ("get-text-property", Fget_text_property, Sget_text_property, 2, 3, 0,
488
  "Return the value of position POS's property PROP, in OBJECT.\n\
489 490
OBJECT is optional and defaults to the current buffer.\n\
If POSITION is at the end of OBJECT, the value is nil.")
491
  (pos, prop, object)
492
     Lisp_Object pos, object;
493 494 495 496 497 498 499 500 501 502 503
     register Lisp_Object prop;
{
  register INTERVAL i;
  register Lisp_Object tail;

  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);
  i = validate_interval_range (object, &pos, &pos, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;

504 505 506 507 508 509 510
  /* If POS is at the end of the interval,
     it means it's the end of OBJECT.
     There are no properties at the very end,
     since no character follows.  */
  if (XINT (pos) == LENGTH (i) + i->position)
    return Qnil;

511
  return textget (i->plist, prop);
512 513
}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
514
DEFUN ("next-property-change", Fnext_property_change,
515 516 517 518 519 520 521
       Snext_property_change, 1, 2, 0,
  "Return the position of next property change.\n\
Scans characters forward from POS in OBJECT till it finds\n\
a change in some text property, then returns the position of the change.\n\
The optional second argument OBJECT is the string or buffer to scan.\n\
Return nil if the property is constant all the way to the end of OBJECT.\n\
If the value is non-nil, it is a position greater than POS, never equal.")
Joseph Arceneaux's avatar
Joseph Arceneaux committed
522 523 524 525 526
  (pos, object)
     Lisp_Object pos, object;
{
  register INTERVAL i, next;

527 528 529
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
530 531 532 533 534 535 536 537 538 539 540
  i = validate_interval_range (object, &pos, &pos, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;

  next = next_interval (i);
  while (! NULL_INTERVAL_P (next) && intervals_equal (i, next))
    next = next_interval (next);

  if (NULL_INTERVAL_P (next))
    return Qnil;

541 542
  return next->position - (XTYPE (object) == Lisp_String);
;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
543 544
}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
545
DEFUN ("next-single-property-change", Fnext_single_property_change,
546 547 548 549 550 551 552 553 554
       Snext_single_property_change, 1, 3, 0,
  "Return the position of next property change for a specific property.\n\
Scans characters forward from POS till it finds\n\
a change in the PROP property, then returns the position of the change.\n\
The optional third argument OBJECT is the string or buffer to scan.\n\
Return nil if the property is constant all the way to the end of OBJECT.\n\
If the value is non-nil, it is a position greater than POS, never equal.")
  (pos, prop, object)
     Lisp_Object pos, prop, object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
555 556 557 558
{
  register INTERVAL i, next;
  register Lisp_Object here_val;

559 560 561
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
562 563 564 565
  i = validate_interval_range (object, &pos, &pos, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;

566
  here_val = textget (i->plist, prop);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
567
  next = next_interval (i);
568 569
  while (! NULL_INTERVAL_P (next) 
	 && EQ (here_val, textget (next->plist, prop)))
Joseph Arceneaux's avatar
Joseph Arceneaux committed
570 571 572 573 574
    next = next_interval (next);

  if (NULL_INTERVAL_P (next))
    return Qnil;

575
  return next->position - (XTYPE (object) == Lisp_String);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
576 577
}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
578
DEFUN ("previous-property-change", Fprevious_property_change,
579 580 581 582 583 584 585
       Sprevious_property_change, 1, 2, 0,
  "Return the position of previous property change.\n\
Scans characters backwards from POS in OBJECT till it finds\n\
a change in some text property, then returns the position of the change.\n\
The optional second argument OBJECT is the string or buffer to scan.\n\
Return nil if the property is constant all the way to the start of OBJECT.\n\
If the value is non-nil, it is a position less than POS, never equal.")
Joseph Arceneaux's avatar
Joseph Arceneaux committed
586 587 588 589 590
  (pos, object)
     Lisp_Object pos, object;
{
  register INTERVAL i, previous;

591 592 593
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
594 595 596 597 598 599 600 601 602 603
  i = validate_interval_range (object, &pos, &pos, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;

  previous = previous_interval (i);
  while (! NULL_INTERVAL_P (previous) && intervals_equal (previous, i))
    previous = previous_interval (previous);
  if (NULL_INTERVAL_P (previous))
    return Qnil;

604 605
  return (previous->position + LENGTH (previous) - 1
	  - (XTYPE (object) == Lisp_String));
Joseph Arceneaux's avatar
Joseph Arceneaux committed
606 607
}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
608
DEFUN ("previous-single-property-change", Fprevious_single_property_change,
609 610 611 612 613 614 615 616 617
       Sprevious_single_property_change, 2, 3, 0,
  "Return the position of previous property change for a specific property.\n\
Scans characters backward from POS till it finds\n\
a change in the PROP property, then returns the position of the change.\n\
The optional third argument OBJECT is the string or buffer to scan.\n\
Return nil if the property is constant all the way to the start of OBJECT.\n\
If the value is non-nil, it is a position less than POS, never equal.")
     (pos, prop, object)
     Lisp_Object pos, prop, object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
618 619 620 621
{
  register INTERVAL i, previous;
  register Lisp_Object here_val;

622 623 624
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
625 626 627 628
  i = validate_interval_range (object, &pos, &pos, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;

629
  here_val = textget (i->plist, prop);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
630 631
  previous = previous_interval (i);
  while (! NULL_INTERVAL_P (previous)
632
	 && EQ (here_val, textget (previous->plist, prop)))
Joseph Arceneaux's avatar
Joseph Arceneaux committed
633 634 635 636
    previous = previous_interval (previous);
  if (NULL_INTERVAL_P (previous))
    return Qnil;

637 638
  return (previous->position + LENGTH (previous) - 1
	  - (XTYPE (object) == Lisp_String));
Joseph Arceneaux's avatar
Joseph Arceneaux committed
639 640
}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
641
DEFUN ("add-text-properties", Fadd_text_properties,
642 643 644 645 646 647 648 649 650
       Sadd_text_properties, 3, 4, 0,
  "Add properties to the text from START to END.\n\
The third argument PROPS is a property list\n\
specifying the property values to add.\n\
The optional fourth argument, OBJECT,\n\
is the string or buffer containing the text.\n\
Return t if any property value actually changed, nil otherwise.")
  (start, end, properties, object)
     Lisp_Object start, end, properties, object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
651 652
{
  register INTERVAL i, unchanged;
653
  register int s, len, modified = 0;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
654 655 656 657 658

  properties = validate_plist (properties);
  if (NILP (properties))
    return Qnil;

659 660 661
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680
  i = validate_interval_range (object, &start, &end, hard);
  if (NULL_INTERVAL_P (i))
    return Qnil;

  s = XINT (start);
  len = XINT (end) - s;

  /* If we're not starting on an interval boundary, we have to
    split this interval. */
  if (i->position != s)
    {
      /* If this interval already has the properties, we can
         skip it. */
      if (interval_has_all_properties (properties, i))
	{
	  int got = (LENGTH (i) - (s - i->position));
	  if (got >= len)
	    return Qnil;
	  len -= got;
681
	  i = next_interval (i);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
682 683 684 685 686 687 688 689 690
	}
      else
	{
	  unchanged = i;
	  i = split_interval_right (unchanged, s - unchanged->position + 1);
	  copy_properties (unchanged, i);
	}
    }

691
  /* We are at the beginning of interval I, with LEN chars to scan.  */
692
  for (;;)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
693
    {
694 695 696
      if (i == 0)
	abort ();

Joseph Arceneaux's avatar
Joseph Arceneaux committed
697 698 699 700 701 702 703
      if (LENGTH (i) >= len)
	{
	  if (interval_has_all_properties (properties, i))
	    return modified ? Qt : Qnil;

	  if (LENGTH (i) == len)
	    {
704
	      add_properties (properties, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
705 706 707 708 709 710 711
	      return Qt;
	    }

	  /* i doesn't have the properties, and goes past the change limit */
	  unchanged = i;
	  i = split_interval_left (unchanged, len + 1);
	  copy_properties (unchanged, i);
712
	  add_properties (properties, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
713 714 715 716
	  return Qt;
	}

      len -= LENGTH (i);
717
      modified += add_properties (properties, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
718 719 720 721
      i = next_interval (i);
    }
}

722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737
DEFUN ("put-text-property", Fput_text_property,
       Sput_text_property, 4, 5, 0,
  "Set one property of the text from START to END.\n\
The third and fourth arguments PROP and VALUE\n\
specify the property to add.\n\
The optional fifth argument, OBJECT,\n\
is the string or buffer containing the text.")
  (start, end, prop, value, object)
     Lisp_Object start, end, prop, value, object;
{
  Fadd_text_properties (start, end,
			Fcons (prop, Fcons (value, Qnil)),
			object);
  return Qnil;
}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
738
DEFUN ("set-text-properties", Fset_text_properties,
739 740 741 742 743 744 745
       Sset_text_properties, 3, 4, 0,
  "Completely replace properties of text from START to END.\n\
The third argument PROPS is the new property list.\n\
The optional fourth argument, OBJECT,\n\
is the string or buffer containing the text.")
  (start, end, props, object)
     Lisp_Object start, end, props, object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
746 747
{
  register INTERVAL i, unchanged;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
748
  register INTERVAL prev_changed = NULL_INTERVAL;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
749 750
  register int s, len;

751
  props = validate_plist (props);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
752

753 754 755
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
756 757 758 759 760 761 762 763 764 765 766
  i = validate_interval_range (object, &start, &end, hard);
  if (NULL_INTERVAL_P (i))
    return Qnil;

  s = XINT (start);
  len = XINT (end) - s;

  if (i->position != s)
    {
      unchanged = i;
      i = split_interval_right (unchanged, s - unchanged->position + 1);
767

Joseph Arceneaux's avatar
Joseph Arceneaux committed
768 769
      if (LENGTH (i) > len)
	{
Joseph Arceneaux's avatar
Joseph Arceneaux committed
770
	  copy_properties (unchanged, i);
771 772
	  i = split_interval_left (i, len + 1);
	  set_properties (props, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
773 774 775
	  return Qt;
	}

776 777
      set_properties (props, i, object);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
778 779 780 781
      if (LENGTH (i) == len)
	return Qt;

      prev_changed = i;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
782 783 784 785
      len -= LENGTH (i);
      i = next_interval (i);
    }

786
  /* We are starting at the beginning of an interval, I */
787
  while (len > 0)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
788
    {
789 790 791
      if (i == 0)
	abort ();

Joseph Arceneaux's avatar
Joseph Arceneaux committed
792 793
      if (LENGTH (i) >= len)
	{
794 795
	  if (LENGTH (i) > len)
	    i = split_interval_left (i, len + 1);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
796

Joseph Arceneaux's avatar
Joseph Arceneaux committed
797
	  if (NULL_INTERVAL_P (prev_changed))
798
	    set_properties (props, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
799 800
	  else
	    merge_interval_left (i);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
801 802 803 804
	  return Qt;
	}

      len -= LENGTH (i);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
805 806
      if (NULL_INTERVAL_P (prev_changed))
	{
807
	  set_properties (props, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
808 809 810 811 812
	  prev_changed = i;
	}
      else
	prev_changed = i = merge_interval_left (i);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
813 814 815 816 817 818 819
      i = next_interval (i);
    }

  return Qt;
}

DEFUN ("remove-text-properties", Fremove_text_properties,
820 821 822 823 824 825 826 827 828 829
       Sremove_text_properties, 3, 4, 0,
  "Remove some properties from text from START to END.\n\
The third argument PROPS is a property list\n\
whose property names specify the properties to remove.\n\
\(The values stored in PROPS are ignored.)\n\
The optional fourth argument, OBJECT,\n\
is the string or buffer containing the text.\n\
Return t if any property was actually removed, nil otherwise.")
  (start, end, props, object)
     Lisp_Object start, end, props, object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
830 831
{
  register INTERVAL i, unchanged;
832
  register int s, len, modified = 0;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
833

834 835 836
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
837 838 839 840 841 842
  i = validate_interval_range (object, &start, &end, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;

  s = XINT (start);
  len = XINT (end) - s;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
843

Joseph Arceneaux's avatar
Joseph Arceneaux committed
844 845 846 847
  if (i->position != s)
    {
      /* No properties on this first interval -- return if
         it covers the entire region. */
848
      if (! interval_has_some_properties (props, i))
Joseph Arceneaux's avatar
Joseph Arceneaux committed
849 850 851 852 853
	{
	  int got = (LENGTH (i) - (s - i->position));
	  if (got >= len)
	    return Qnil;
	  len -= got;
854
	  i = next_interval (i);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
855
	}
856 857
      /* Split away the beginning of this interval; what we don't
	 want to modify.  */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
858 859 860 861 862 863 864 865 866
      else
	{
	  unchanged = i;
	  i = split_interval_right (unchanged, s - unchanged->position + 1);
	  copy_properties (unchanged, i);
	}
    }

  /* We are at the beginning of an interval, with len to scan */
867
  for (;;)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
868
    {
869 870 871
      if (i == 0)
	abort ();

Joseph Arceneaux's avatar
Joseph Arceneaux committed
872 873
      if (LENGTH (i) >= len)
	{
874
	  if (! interval_has_some_properties (props, i))
Joseph Arceneaux's avatar
Joseph Arceneaux committed
875 876 877 878
	    return modified ? Qt : Qnil;

	  if (LENGTH (i) == len)
	    {
879
	      remove_properties (props, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
880 881 882 883
	      return Qt;
	    }

	  /* i has the properties, and goes past the change limit */
884 885
	  unchanged = i;
	  i = split_interval_left (i, len + 1);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
886
	  copy_properties (unchanged, i);
887
	  remove_properties (props, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
888 889 890 891
	  return Qt;
	}

      len -= LENGTH (i);
892
      modified += remove_properties (props, i, object);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
893 894 895 896
      i = next_interval (i);
    }
}

897 898
#if 0 /* You can use set-text-properties for this.  */

Joseph Arceneaux's avatar
Joseph Arceneaux committed
899
DEFUN ("erase-text-properties", Ferase_text_properties,
900 901 902 903 904 905
       Serase_text_properties, 2, 3, 0,
  "Remove all properties from the text from START to END.\n\
The optional third argument, OBJECT,\n\
is the string or buffer containing the text.")
  (start, end, object)
     Lisp_Object start, end, object;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
906
{
907
  register INTERVAL i;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
908
  register INTERVAL prev_changed = NULL_INTERVAL;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
909 910
  register int s, len, modified;

911 912 913
  if (NILP (object))
    XSET (object, Lisp_Buffer, current_buffer);

Joseph Arceneaux's avatar
Joseph Arceneaux committed
914 915 916 917 918 919
  i = validate_interval_range (object, &start, &end, soft);
  if (NULL_INTERVAL_P (i))
    return Qnil;

  s = XINT (start);
  len = XINT (end) - s;
920

Joseph Arceneaux's avatar
Joseph Arceneaux committed
921 922
  if (i->position != s)
    {
923
      register int got;
924
      register INTERVAL unchanged = i;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
925

926
      /* If there are properties here, then this text will be modified. */
927
      if (! NILP (i->plist))
Joseph Arceneaux's avatar
Joseph Arceneaux committed
928 929
	{
	  i = split_interval_right (unchanged, s - unchanged->position + 1);
930
	  i->plist = Qnil;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
931
	  modified++;
932 933 934 935 936 937 938 939 940 941 942 943

	  if (LENGTH (i) > len)
	    {
	      i = split_interval_right (i, len + 1);
	      copy_properties (unchanged, i);
	      return Qt;
	    }

	  if (LENGTH (i) == len)
	    return Qt;

	  got = LENGTH (i);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
944
	}
945 946 947
      /* If the text of I is without any properties, and contains
         LEN or more characters, then we may return without changing
	 anything.*/
948 949
      else if (LENGTH (i) - (s - i->position) <= len)
	return Qnil;
950 951
      /* The amount of text to change extends past I, so just note
	 how much we've gotten. */
952 953
      else
	got = LENGTH (i) - (s - i->position);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
954 955

      len -= got;
956
      prev_changed = i;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
957 958 959
      i = next_interval (i);
    }

960
  /* We are starting at the beginning of an interval, I. */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
961 962
  while (len > 0)
    {
963
      if (LENGTH (i) >= len)
Joseph Arceneaux's avatar
Joseph Arceneaux committed
964
	{
965 966
	  /* If I has no properties, simply merge it if possible.  */
	  if (NILP (i->plist))
967 968 969
	    {
	      if (! NULL_INTERVAL_P (prev_changed))
		merge_interval_left (i);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
970

971 972 973
	      return modified ? Qt : Qnil;
	    }

974 975
          if (LENGTH (i) > len)
            i = split_interval_left (i, len + 1);
976 977
	  if (! NULL_INTERVAL_P (prev_changed))
	    merge_interval_left (i);
978 979
	  else
	    i->plist = Qnil;
980

981
	  return Qt;
Joseph Arceneaux's avatar
Joseph Arceneaux committed
982 983
	}

984
      /* Here if we still need to erase past the end of I */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
985
      len -= LENGTH (i);
986 987 988 989 990 991 992
      if (NULL_INTERVAL_P (prev_changed))
	{
	  modified += erase_properties (i);
	  prev_changed = i;
	}
      else
	{
993 994
	  modified += ! NILP (i->plist);
	  /* Merging I will give it the properties of PREV_CHANGED. */
995 996 997
	  prev_changed = i = merge_interval_left (i);
	}

Joseph Arceneaux's avatar
Joseph Arceneaux committed
998 999 1000 1001 1002
      i = next_interval (i);
    }

  return modified ? Qt : Qnil;
}
1003
#endif /* 0 */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1004 1005 1006 1007 1008

void
syms_of_textprop ()
{
  DEFVAR_INT ("interval-balance-threshold", &interval_balance_threshold,
1009
	      "Threshold for rebalancing interval trees, expressed as the\n\
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028
percentage by which the left interval tree should not differ from the right.");
  interval_balance_threshold = 8;

  /* Common attributes one might give text */

  staticpro (&Qforeground);
  Qforeground = intern ("foreground");
  staticpro (&Qbackground);
  Qbackground = intern ("background");
  staticpro (&Qfont);
  Qfont = intern ("font");
  staticpro (&Qstipple);
  Qstipple = intern ("stipple");
  staticpro (&Qunderline);
  Qunderline = intern ("underline");
  staticpro (&Qread_only);
  Qread_only = intern ("read-only");
  staticpro (&Qinvisible);
  Qinvisible = intern ("invisible");
1029 1030 1031 1032
  staticpro (&Qcategory);
  Qcategory = intern ("category");
  staticpro (&Qlocal_map);
  Qlocal_map = intern ("local-map");
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043

  /* Properties that text might use to specify certain actions */

  staticpro (&Qmouse_left);
  Qmouse_left = intern ("mouse-left");
  staticpro (&Qmouse_entered);
  Qmouse_entered = intern ("mouse-entered");
  staticpro (&Qpoint_left);
  Qpoint_left = intern ("point-left");
  staticpro (&Qpoint_entered);
  Qpoint_entered = intern ("point-entered");
1044 1045
  staticpro (&Qmodification_hooks);
  Qmodification_hooks = intern ("modification-hooks");
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1046 1047

  defsubr (&Stext_properties_at);
1048
  defsubr (&Sget_text_property);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1049
  defsubr (&Snext_property_change);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1050
  defsubr (&Snext_single_property_change);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1051
  defsubr (&Sprevious_property_change);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1052
  defsubr (&Sprevious_single_property_change);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1053
  defsubr (&Sadd_text_properties);
1054
  defsubr (&Sput_text_property);
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1055 1056
  defsubr (&Sset_text_properties);
  defsubr (&Sremove_text_properties);
1057
/*  defsubr (&Serase_text_properties); */
Joseph Arceneaux's avatar
Joseph Arceneaux committed
1058
}
1059 1060 1061 1062 1063 1064

#else

lose -- this shouldn't be compiled if USE_TEXT_PROPERTIES isn't defined

#endif /* USE_TEXT_PROPERTIES */