view src/marker.c @ 1330:4542b72c005e

[xemacs-hg @ 2003-03-01 07:25:26 by ben] build patch Makefile.in.in: Move src deletions to src/Makefile.in.in. dump-paths.el, dumped-lisp.el: Delete. Combine stuff into setup-paths.el. find-paths.el: Removed. Make this file contain generic routines only. Move stuff to compute Emacs roots to setup-paths.el. startup.el: Removed. Move these variables into setup-paths.el. setup-paths.el, startup.el: Removed. Combine all high-level code for computing the paths into setup-paths.el. Create new function startup-find-load-path to encapsulate all logic for computing `load-path'. Eliminate invocation-directory and invocation-name parameters since there is no point (false generality) -- the code references other globals, which cannot be specified. Eliminate some code duplicated between setup-paths.el and startup.el. Clean up the debug-paths code and output load-path in addition. Add logic to paths-emacs-root-p to support separated source and build trees. loadup.el, make-docfile.el, update-elc-2.el, update-elc.el: Rewrite to allow for separated source and build trees, as may occur in MS Windows. NOTE TO BUILD HACKERS: loadup.el, make-docfile.el, update-elc.el and update-elc-2.el made two assumptions that are no longer correct: (1) The source and build trees are in the same place. (2) They can make assumptions about where `.' is. These files now compute the locations of the source and build roots at the top of the file. *ALL* constant file names or path snippets must now be made absolute using expand-file-name and one of these roots. dumped-lisp.el, packages.el: Removed. Remove some unused lists of Lisp files. packages-hardcoded-lisp (empty, in any case) moved to dumped-lisp.el. startup.el: When a compiled init file is out-of-date wrt the uncompiled version, load the uncompiled version and issue a nasty warning. update-elc-2.el: Force touching of auto-autoloads files when REBUILD_AUTOLOADS was set. update-elc.el: Fix code that checks whether dumping is necessary to check against xemacs.dmp, not xemacs.exe, when Unix and pdump. lwlib-Xm.c: Fix compile warning. README, config.inc.samp, xemacs.mak: -- Major reorganization and cleanup. -- Add support for separated build tree and source tree. -- Delete all support for X Windows building, since it's totally bit-rotten and will never be fixed up. Instruct people to use Cygwin if they want such support. make-build-dir: New script to create a skeleton build tree for use with separated build and source tree compilation. m/acorn.h, m/alliant-2800.h, m/alliant.h, m/altos.h, m/amdahl.h, m/arm.h, m/att3b.h, m/aviion.h, m/clipper.h, m/cnvrgnt.h, m/convex.h, m/cydra5.h, m/delta.h, m/delta88k.h, m/dpx2.h, m/elxsi.h, m/ews4800r.h, m/gould.h, m/hp800.h, m/hp9000s300.h, m/i860.h, m/ibmps2-aix.h, m/ibmrs6000.h, m/ibmrt-aix.h, m/ibmrt.h, m/intel386.h, m/iris4d.h, m/iris5d.h, m/iris6d.h, m/irist.h, m/m68k.h, m/masscomp.h, m/mg1.h, m/mips-nec.h, m/mips-siemens.h, m/mips.h, m/nh3000.h, m/nh4000.h, m/ns32000.h, m/plexus.h, m/powerpc.h, m/sequent-ptx.h, m/sequent.h, m/sgi-challenge.h, m/stride.h, m/tad68k.h, m/targon31.h, m/tekxd88.h, m/template.h, m/tower32.h, m/tower32v3.h, m/ustation.h, m/wicat.h, m/xps100.h, data.c, doc.c, editfns.c, emacs.c, lrecord.h, ntheap.c, process-unix.c, sysdep.c, unexec.c: Delete all support for bit-rotten CANNOT_DUMP. Just use pdump. Makefile.in.in: Lots o' cleanup. Use names like LISP, SRC instead of lispdir, srcdir, for consistency with xemacs.mak and the conventions in the rest of the file. Eliminate use of ${...} in favor of $(...), to make it easier to move code between this file and xemacs.mak. Fix dependency handling wrt NEEDTODUMP to eliminate problems some people (e.g. Vin) have been seeing with non-GNU makes. Write a long section about the subtle but oh-so-important differences in dependency processing between nmake, make, and GNU make. Add unicode-encapsulate target, from xemacs.mak. chartab.c, lrecord.h: Fix crash due to attempt to free objects across dump/undump.
author ben
date Sat, 01 Mar 2003 07:25:56 +0000
parents e22b0213b713
children 04bc9d2f42c7
line wrap: on
line source

/* Markers: examining, setting and killing.
   Copyright (C) 1985, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
   Copyright (C) 2002 Ben Wing.

This file is part of XEmacs.

XEmacs is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.

XEmacs 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 XEmacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* Synched up with: FSF 19.30. */

/* This file has been Mule-ized. */

/* Note that markers are currently kept in an unordered list.
   This means that marker operations may be inefficient if
   there are a bunch of markers in the buffer.  This probably
   won't have a significant impact on redisplay (which uses
   markers), but if it does, it wouldn't be too hard to change
   to an ordered gap array. (Just copy the code from extents.c.)
   */

#include <config.h>
#include "lisp.h"

#include "buffer.h"

static Lisp_Object
mark_marker (Lisp_Object obj)
{
  Lisp_Marker *marker = XMARKER (obj);
  Lisp_Object buf;
  /* DO NOT mark through the marker's chain.
     The buffer's markers chain does not preserve markers from gc;
     Instead, markers are removed from the chain when they are freed
     by gc.
   */
  if (!marker->buffer)
    return (Qnil);

  buf = wrap_buffer (marker->buffer);
  return (buf);
}

static void
print_marker (Lisp_Object obj, Lisp_Object printcharfun, int escapeflag)
{
  Lisp_Marker *marker = XMARKER (obj);

  if (print_readably)
    printing_unreadable_object ("#<marker 0x%lx>", (long) marker);

  write_c_string (printcharfun, GETTEXT ("#<marker "));
  if (!marker->buffer)
    write_c_string (printcharfun, GETTEXT ("in no buffer"));
  else
    {
      write_fmt_string (printcharfun, "at %ld in ",
			(long) marker_position (obj));
      print_internal (marker->buffer->name, printcharfun, 0);
    }
  if (marker->insertion_type)
    write_c_string (printcharfun, " insertion-type=t");
  write_fmt_string (printcharfun, " 0x%lx>", (long) marker);
}

static int
marker_equal (Lisp_Object obj1, Lisp_Object obj2, int depth)
{
  Lisp_Marker *marker1 = XMARKER (obj1);
  Lisp_Marker *marker2 = XMARKER (obj2);

  return ((marker1->buffer == marker2->buffer) &&
	  (marker1->membpos == marker2->membpos ||
	  /* All markers pointing nowhere are equal */
	   !marker1->buffer));
}

static unsigned long
marker_hash (Lisp_Object obj, int depth)
{
  unsigned long hash = (unsigned long) XMARKER (obj)->buffer;
  if (hash)
    hash = HASH2 (hash, XMARKER (obj)->membpos);
  return hash;
}

static const struct memory_description marker_description[] = {
  { XD_LISP_OBJECT, offsetof (Lisp_Marker, next), 0, 0, XD_FLAG_NO_KKCC },
  { XD_LISP_OBJECT, offsetof (Lisp_Marker, prev), 0, 0, XD_FLAG_NO_KKCC },
  { XD_LISP_OBJECT, offsetof (Lisp_Marker, buffer) },
  { XD_END }
};

DEFINE_BASIC_LRECORD_IMPLEMENTATION ("marker", marker,
				     1, /*dumpable-flag*/
				     mark_marker, print_marker, 0,
				     marker_equal, marker_hash,
				     marker_description, Lisp_Marker);

/* Operations on markers. */

DEFUN ("marker-buffer", Fmarker_buffer, 1, 1, 0, /*
Return the buffer that MARKER points into, or nil if none.
Return nil if MARKER points into a dead buffer or doesn't point anywhere.
*/
       (marker))
{
  struct buffer *buf;
  CHECK_MARKER (marker);
  /* Return marker's buffer only if it is not dead.  */
  if ((buf = XMARKER (marker)->buffer) && BUFFER_LIVE_P (buf))
    {
      return wrap_buffer (buf);
    }
  return Qnil;
}

DEFUN ("marker-position", Fmarker_position, 1, 1, 0, /*
Return the position MARKER points at, as a character number.
Return `nil' if marker doesn't point anywhere.
*/
       (marker))
{
  CHECK_MARKER (marker);
  return XMARKER (marker)->buffer ? make_int (marker_position (marker)) : Qnil;
}

#if 0 /* useful debugging function */

static void
check_marker_circularities (struct buffer *buf)
{
  Lisp_Marker *tortoise, *hare;

  tortoise = BUF_MARKERS (buf);
  hare = tortoise;

  if (!tortoise)
    return;

  while (1)
    {
      assert (hare->buffer == buf);
      hare = hare->next;
      if (!hare)
        return;
      assert (hare->buffer == buf);
      hare = hare->next;
      if (!hare)
        return;
      tortoise = tortoise->next;
      assert (tortoise != hare);
    }
}

#endif

static Lisp_Object
set_marker_internal (Lisp_Object marker, Lisp_Object position,
		     Lisp_Object buffer, int restricted_p)
{
  Charbpos charno;
  struct buffer *b;
  Lisp_Marker *m;
  int point_p;

  CHECK_MARKER (marker);

  point_p = POINT_MARKER_P (marker);

  /* If position is nil or a marker that points nowhere,
     make this marker point nowhere.  */
  if (NILP (position) ||
      (MARKERP (position) && !XMARKER (position)->buffer))
    {
      if (point_p)
	invalid_operation ("Can't make point-marker point nowhere",
			   marker);
      if (XMARKER (marker)->buffer)
	unchain_marker (marker);
      return marker;
    }

  CHECK_INT_COERCE_MARKER (position);
  if (NILP (buffer))
    b = current_buffer;
  else
    {
      CHECK_BUFFER (buffer);
      b = XBUFFER (buffer);
      /* If buffer is dead, set marker to point nowhere.  */
      if (!BUFFER_LIVE_P (XBUFFER (buffer)))
	{
	  if (point_p)
	    invalid_operation
	      ("Can't move point-marker in a killed buffer", marker);
	  if (XMARKER (marker)->buffer)
	    unchain_marker (marker);
	  return marker;
	}
    }

  charno = XINT (position);
  m = XMARKER (marker);

  if (restricted_p)
    {
      if (charno < BUF_BEGV (b)) charno = BUF_BEGV (b);
      if (charno > BUF_ZV (b)) charno = BUF_ZV (b);
    }
  else
    {
      if (charno < BUF_BEG (b)) charno = BUF_BEG (b);
      if (charno > BUF_Z (b)) charno = BUF_Z (b);
    }

  if (point_p)
    {
#ifndef moving_point_by_moving_its_marker_is_a_bug
      BUF_SET_PT (b, charno);	/* this will move the marker */
#else  /* It's not a feature, so it must be a bug */
      invalid_operation ("DEBUG: attempt to move point via point-marker",
			 marker);
#endif
    }
  else
    {
      m->membpos = charbpos_to_membpos (b, charno);
    }

  if (m->buffer != b)
    {
      if (point_p)
	invalid_operation ("Can't change buffer of point-marker", marker);
      if (m->buffer != 0)
	unchain_marker (marker);
      m->buffer = b;
      marker_next (m) = BUF_MARKERS (b);
      marker_prev (m) = 0;
      if (BUF_MARKERS (b))
        marker_prev (BUF_MARKERS (b)) = m;
      BUF_MARKERS (b) = m;
    }

  return marker;
}


DEFUN ("set-marker", Fset_marker, 2, 3, 0, /*
Move MARKER to position POSITION in BUFFER.
POSITION can be a marker, an integer or nil.  If POSITION is an
integer, make MARKER point before the POSITIONth character in BUFFER.
If POSITION is nil, makes MARKER point nowhere.  Then it no longer
slows down editing in any buffer.  If POSITION is less than 1, move
MARKER to the beginning of BUFFER.  If POSITION is greater than the
size of BUFFER, move MARKER to the end of BUFFER.
BUFFER defaults to the current buffer.
If this marker was returned by (point-marker t), then changing its
position moves point.  You cannot change its buffer or make it point
nowhere.
The return value is MARKER.
*/
       (marker, position, buffer))
{
  return set_marker_internal (marker, position, buffer, 0);
}


/* This version of Fset_marker won't let the position
   be outside the visible part.  */
Lisp_Object
set_marker_restricted (Lisp_Object marker, Lisp_Object position,
		       Lisp_Object buffer)
{
  return set_marker_internal (marker, position, buffer, 1);
}


/* This is called during garbage collection,
   so we must be careful to ignore and preserve mark bits,
   including those in chain fields of markers.  */

void
unchain_marker (Lisp_Object m)
{
  Lisp_Marker *marker = XMARKER (m);
  struct buffer *b = marker->buffer;

  if (b == 0)
    return;

#ifdef ERROR_CHECK_STRUCTURES
  assert (BUFFER_LIVE_P (b));
#endif

  if (marker_next (marker))
    marker_prev (marker_next (marker)) = marker_prev (marker);
  if (marker_prev (marker))
    marker_next (marker_prev (marker)) = marker_next (marker);
  else
    BUF_MARKERS (b) = marker_next (marker);

#ifdef ERROR_CHECK_STRUCTURES
  assert (marker != XMARKER (b->point_marker));
#endif

  marker->buffer = 0;
}

Bytebpos
byte_marker_position (Lisp_Object marker)
{
  Lisp_Marker *m = XMARKER (marker);
  struct buffer *buf = m->buffer;
  Bytebpos pos;

  if (!buf)
    invalid_argument ("Marker does not point anywhere", Qunbound);

  /* FSF claims that marker indices could end up denormalized, i.e.
     in the gap.  This is way bogus if it ever happens, and means
     something fucked up elsewhere.  Since I've overhauled all this
     shit, I don't think this can happen.  In any case, the following
     macro has an assert() in it that will catch these denormalized
     positions. */
  pos = membpos_to_bytebpos (buf, m->membpos);

  return pos;
}

Charbpos
marker_position (Lisp_Object marker)
{
  struct buffer *buf = XMARKER (marker)->buffer;

  if (!buf)
    invalid_argument ("Marker does not point anywhere", Qunbound);

  return bytebpos_to_charbpos (buf, byte_marker_position (marker));
}

void
set_byte_marker_position (Lisp_Object marker, Bytebpos pos)
{
  Lisp_Marker *m = XMARKER (marker);
  struct buffer *buf = m->buffer;

  if (!buf)
    invalid_argument ("Marker does not point anywhere", Qunbound);

  m->membpos = bytebpos_to_membpos (buf, pos);
}

void
set_marker_position (Lisp_Object marker, Charbpos pos)
{
  struct buffer *buf = XMARKER (marker)->buffer;

  if (!buf)
    invalid_argument ("Marker does not point anywhere", Qunbound);

  set_byte_marker_position (marker, charbpos_to_bytebpos (buf, pos));
}

static Lisp_Object
copy_marker_1 (Lisp_Object marker, Lisp_Object type, int noseeum)
{
  REGISTER Lisp_Object new;

  while (1)
    {
      if (INTP (marker) || MARKERP (marker))
	{
	  if (noseeum)
	    new = noseeum_make_marker ();
	  else
	    new = Fmake_marker ();
	  Fset_marker (new, marker,
		       (MARKERP (marker) ? Fmarker_buffer (marker) : Qnil));
	  XMARKER (new)->insertion_type = !NILP (type);
	  return new;
	}
      else
	marker = wrong_type_argument (Qinteger_or_marker_p, marker);
    }

  RETURN_NOT_REACHED (Qnil); /* not reached */
}

DEFUN ("copy-marker", Fcopy_marker, 1, 2, 0, /*
Return a new marker pointing at the same place as MARKER-OR-INTEGER.
If MARKER-OR-INTEGER is an integer, return a new marker pointing
at that position in the current buffer.
Optional argument MARKER-TYPE specifies the insertion type of the new
marker; see `marker-insertion-type'.
*/
       (marker_or_integer, marker_type))
{
  return copy_marker_1 (marker_or_integer, marker_type, 0);
}

Lisp_Object
noseeum_copy_marker (Lisp_Object marker, Lisp_Object marker_type)
{
  return copy_marker_1 (marker, marker_type, 1);
}

DEFUN ("marker-insertion-type", Fmarker_insertion_type, 1, 1, 0, /*
Return insertion type of MARKER: t if it stays after inserted text.
nil means the marker stays before text inserted there.
*/
       (marker))
{
  CHECK_MARKER (marker);
  return XMARKER (marker)->insertion_type ? Qt : Qnil;
}

DEFUN ("set-marker-insertion-type", Fset_marker_insertion_type, 2, 2, 0, /*
Set the insertion-type of MARKER to TYPE.
If TYPE is t, it means the marker advances when you insert text at it.
If TYPE is nil, it means the marker stays behind when you insert text at it.
*/
       (marker, type))
{
  CHECK_MARKER (marker);

  XMARKER (marker)->insertion_type = ! NILP (type);
  return type;
}

/* #### What is the possible use of this?  It looks quite useless to
   me, because there is no way to find *which* markers are positioned
   at POSITION.  Additional bogosity bonus: (buffer-has-markers-at
   (point)) will always return t because of the `point-marker'.  The
   same goes for the position of mark.  Bletch!

   Someone should discuss this with Stallman, but I don't have the
   stomach.  In fact, this function sucks so badly that I'm disabling
   it by default (although I've debugged it).  If you want to use it,
   use extents instead.  --hniksic */
#if 0
DEFUN ("buffer-has-markers-at", Fbuffer_has_markers_at, 1, 1, 0, /*
Return t if there are markers pointing at POSITION in the current buffer.
*/
       (position))
{
  Lisp_Marker *marker;
  Membpos pos;

  /* A small optimization trick: convert POS to membpos now, rather
     than converting every marker's memory index to charbpos.  */
  pos = bytebpos_to_membpos (current_buffer,
			  get_buffer_pos_byte (current_buffer, position,
					       GB_COERCE_RANGE));

  for (marker = BUF_MARKERS (current_buffer);
       marker;
       marker = marker_next (marker))
    {
      /* We use marker->membpos, so we don't have to go through the
         unwieldy operation of creating a Lisp_Object for
         marker_position() every time around.  */
      if (marker->membpos == pos)
	return Qt;
    }

  return Qnil;
}
#endif /* 0 */

#ifdef MEMORY_USAGE_STATS

int
compute_buffer_marker_usage (struct buffer *b, struct overhead_stats *ovstats)
{
  Lisp_Marker *m;
  int total = 0;
  int overhead;

  for (m = BUF_MARKERS (b); m; m = m->next)
    total += sizeof (Lisp_Marker);
  ovstats->was_requested += total;
  overhead = fixed_type_block_overhead (total);
  /* #### claiming this is all malloc overhead is not really right,
     but it has to go somewhere. */
  ovstats->malloc_overhead += overhead;
  return total + overhead;
}

#endif /* MEMORY_USAGE_STATS */


void
syms_of_marker (void)
{
  INIT_LRECORD_IMPLEMENTATION (marker);

  DEFSUBR (Fmarker_position);
  DEFSUBR (Fmarker_buffer);
  DEFSUBR (Fset_marker);
  DEFSUBR (Fcopy_marker);
  DEFSUBR (Fmarker_insertion_type);
  DEFSUBR (Fset_marker_insertion_type);
#if 0 /* FSFmacs crock */
  DEFSUBR (Fbuffer_has_markers_at);
#endif
}

void
init_buffer_markers (struct buffer *b)
{
  Lisp_Object buf = wrap_buffer (b);

  b->mark = Fmake_marker ();
  BUF_MARKERS (b) = 0;
  b->point_marker = Fmake_marker ();
  Fset_marker (b->point_marker,
	       /* For indirect buffers, point is already set.  */
	       b->base_buffer ? make_int (BUF_PT (b)) : make_int (1),
	       buf);
}

void
uninit_buffer_markers (struct buffer *b)
{
  /* Unchain all markers of this buffer
     and leave them pointing nowhere.  */
  REGISTER Lisp_Marker *m, *next;
  for (m = BUF_MARKERS (b); m; m = next)
    {
      m->buffer = 0;
      next = marker_next (m);
      marker_next (m) = 0;
      marker_prev (m) = 0;
    }
  BUF_MARKERS (b) = 0;
}