/* Markers: examining, setting and deleting.
- Copyright (C) 1985, 1997, 1998 Free Software Foundation, Inc.
+ Copyright (C) 1985, 1997, 1998, 2001, 2002, 2003, 2004,
+ 2005, 2006, 2007 Free Software Foundation, Inc.
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
-the Free Software Foundation; either version 2, or (at your option)
+the Free Software Foundation; either version 3, or (at your option)
any later version.
GNU Emacs is distributed in the hope that it will be useful,
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, Inc., 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA. */
#include <config.h>
/* Converting between character positions and byte positions. */
/* There are several places in the buffer where we know
- the corrspondence: BEG, BEGV, PT, GPT, ZV and Z,
+ the correspondence: BEG, BEGV, PT, GPT, ZV and Z,
and everywhere there is a marker. So we find the one of these places
that is closest to the specified position, and scan from there. */
struct buffer *b;
int charpos;
{
- Lisp_Object tail;
+ struct Lisp_Marker *tail;
int best_above, best_above_byte;
int best_below, best_below_byte;
if (b == cached_buffer && BUF_MODIFF (b) == cached_modiff)
CONSIDER (cached_charpos, cached_bytepos);
- tail = BUF_MARKERS (b);
- while (! NILP (tail))
+ for (tail = BUF_MARKERS (b); tail; tail = tail->next)
{
- CONSIDER (XMARKER (tail)->charpos, XMARKER (tail)->bytepos);
+ CONSIDER (tail->charpos, tail->bytepos);
/* If we are down to a range of 50 chars,
don't bother checking any other markers;
scan the intervening chars directly now. */
if (best_above - best_below < 50)
break;
-
- tail = XMARKER (tail)->chain;
}
/* We get here if we did not exactly hit one of the known places.
}
#undef CONSIDER
+
+/* Used for debugging: recompute the bytepos corresponding to CHARPOS
+ in the simplest, most reliable way. */
+
+int
+verify_bytepos (charpos)
+ int charpos;
+{
+ int below = 1;
+ int below_byte = 1;
+
+ while (below != charpos)
+ {
+ below++;
+ BUF_INC_POS (current_buffer, below_byte);
+ }
+
+ return below_byte;
+}
\f
/* bytepos_to_charpos returns the char position corresponding to BYTEPOS. */
struct buffer *b;
int bytepos;
{
- Lisp_Object tail;
+ struct Lisp_Marker *tail;
int best_above, best_above_byte;
int best_below, best_below_byte;
if (b == cached_buffer && BUF_MODIFF (b) == cached_modiff)
CONSIDER (cached_bytepos, cached_charpos);
- tail = BUF_MARKERS (b);
- while (! NILP (tail))
+ for (tail = BUF_MARKERS (b); tail; tail = tail->next)
{
- CONSIDER (XMARKER (tail)->bytepos, XMARKER (tail)->charpos);
+ CONSIDER (tail->bytepos, tail->charpos);
/* If we are down to a range of 50 chars,
don't bother checking any other markers;
scan the intervening chars directly now. */
if (best_above - best_below < 50)
break;
-
- tail = XMARKER (tail)->chain;
}
/* We get here if we did not exactly hit one of the known places.
It will last until the next GC.
But don't do it if BUF_MARKERS is nil;
that is a signal from Fset_buffer_multibyte. */
- if (record && ! NILP (BUF_MARKERS (b)))
+ if (record && BUF_MARKERS (b))
{
Lisp_Object marker, buffer;
marker = Fmake_marker ();
It will last until the next GC.
But don't do it if BUF_MARKERS is nil;
that is a signal from Fset_buffer_multibyte. */
- if (record && ! NILP (BUF_MARKERS (b)))
+ if (record && BUF_MARKERS (b))
{
Lisp_Object marker, buffer;
marker = Fmake_marker ();
if (XMARKER (marker)->buffer)
{
XSETBUFFER (buf, XMARKER (marker)->buffer);
- /* Return marker's buffer only if it is not dead. */
- if (!NILP (XBUFFER (buf)->name))
- return buf;
+ /* If the buffer is dead, we're in trouble: the buffer pointer here
+ does not preserve the buffer from being GC'd (it's weak), so
+ markers have to be unlinked from their buffer as soon as the buffer
+ is killed. */
+ eassert (!NILP (XBUFFER (buf)->name));
+ return buf;
}
return Qnil;
}
DEFUN ("marker-position", Fmarker_position, Smarker_position, 1, 1, 0,
- doc: /* Return the position MARKER points at, as a character number. */)
+ doc: /* Return the position MARKER points at, as a character number.
+Returns nil if MARKER points nowhere. */)
(marker)
Lisp_Object marker;
{
register struct Lisp_Marker *m;
CHECK_MARKER (marker);
+ m = XMARKER (marker);
+
/* If position is nil or a marker that points nowhere,
make this marker point nowhere. */
if (NILP (position)
|| (MARKERP (position) && !XMARKER (position)->buffer))
{
- unchain_marker (marker);
+ unchain_marker (m);
return marker;
}
/* If buffer is dead, set marker to point nowhere. */
if (EQ (b->name, Qnil))
{
- unchain_marker (marker);
+ unchain_marker (m);
return marker;
}
}
- m = XMARKER (marker);
-
/* Optimize the special case where we are copying the position
of an existing marker, and MARKER is already in the same buffer. */
if (MARKERP (position) && b == XMARKER (position)->buffer
if (m->buffer != b)
{
- unchain_marker (marker);
+ unchain_marker (m);
m->buffer = b;
- m->chain = BUF_MARKERS (b);
- BUF_MARKERS (b) = marker;
+ m->next = BUF_MARKERS (b);
+ BUF_MARKERS (b) = m;
}
-
+
return marker;
}
/* This version of Fset_marker won't let the position
be outside the visible part. */
-Lisp_Object
+Lisp_Object
set_marker_restricted (marker, pos, buffer)
Lisp_Object marker, pos, buffer;
{
register struct Lisp_Marker *m;
CHECK_MARKER (marker);
+ m = XMARKER (marker);
+
/* If position is nil or a marker that points nowhere,
make this marker point nowhere. */
if (NILP (pos)
|| (MARKERP (pos) && !XMARKER (pos)->buffer))
{
- unchain_marker (marker);
+ unchain_marker (m);
return marker;
}
/* If buffer is dead, set marker to point nowhere. */
if (EQ (b->name, Qnil))
{
- unchain_marker (marker);
+ unchain_marker (m);
return marker;
}
}
- m = XMARKER (marker);
-
/* Optimize the special case where we are copying the position
of an existing marker, and MARKER is already in the same buffer. */
if (MARKERP (pos) && b == XMARKER (pos)->buffer
if (m->buffer != b)
{
- unchain_marker (marker);
+ unchain_marker (m);
m->buffer = b;
- m->chain = BUF_MARKERS (b);
- BUF_MARKERS (b) = marker;
+ m->next = BUF_MARKERS (b);
+ BUF_MARKERS (b) = m;
}
-
+
return marker;
}
\f
/* Set the position of MARKER, specifying both the
character position and the corresponding byte position. */
-Lisp_Object
+Lisp_Object
set_marker_both (marker, buffer, charpos, bytepos)
Lisp_Object marker, buffer;
int charpos, bytepos;
register struct Lisp_Marker *m;
CHECK_MARKER (marker);
+ m = XMARKER (marker);
if (NILP (buffer))
b = current_buffer;
/* If buffer is dead, set marker to point nowhere. */
if (EQ (b->name, Qnil))
{
- unchain_marker (marker);
+ unchain_marker (m);
return marker;
}
}
- m = XMARKER (marker);
-
/* In a single-byte buffer, the two positions must be equal. */
if (BUF_Z (b) == BUF_Z_BYTE (b)
&& charpos != bytepos)
if (m->buffer != b)
{
- unchain_marker (marker);
+ unchain_marker (m);
m->buffer = b;
- m->chain = BUF_MARKERS (b);
- BUF_MARKERS (b) = marker;
+ m->next = BUF_MARKERS (b);
+ BUF_MARKERS (b) = m;
}
-
+
return marker;
}
/* This version of set_marker_both won't let the position
be outside the visible part. */
-Lisp_Object
+Lisp_Object
set_marker_restricted_both (marker, buffer, charpos, bytepos)
Lisp_Object marker, buffer;
int charpos, bytepos;
register struct Lisp_Marker *m;
CHECK_MARKER (marker);
+ m = XMARKER (marker);
if (NILP (buffer))
b = current_buffer;
/* If buffer is dead, set marker to point nowhere. */
if (EQ (b->name, Qnil))
{
- unchain_marker (marker);
+ unchain_marker (m);
return marker;
}
}
- m = XMARKER (marker);
-
if (charpos < BUF_BEGV (b))
charpos = BUF_BEGV (b);
if (charpos > BUF_ZV (b))
if (m->buffer != b)
{
- unchain_marker (marker);
+ unchain_marker (m);
m->buffer = b;
- m->chain = BUF_MARKERS (b);
- BUF_MARKERS (b) = marker;
+ m->next = BUF_MARKERS (b);
+ BUF_MARKERS (b) = m;
}
-
+
return marker;
}
\f
void
unchain_marker (marker)
- register Lisp_Object marker;
+ register struct Lisp_Marker *marker;
{
- register Lisp_Object tail, prev, next;
- register EMACS_INT omark;
+ register struct Lisp_Marker *tail, *prev, *next;
register struct buffer *b;
- b = XMARKER (marker)->buffer;
+ b = marker->buffer;
if (b == 0)
return;
if (EQ (b->name, Qnil))
abort ();
- XMARKER (marker)->buffer = 0;
+ marker->buffer = 0;
tail = BUF_MARKERS (b);
- prev = Qnil;
- while (! GC_NILP (tail))
+ prev = NULL;
+ while (tail)
{
- next = XMARKER (tail)->chain;
- XUNMARK (next);
+ next = tail->next;
- if (XMARKER (marker) == XMARKER (tail))
+ if (marker == tail)
{
- if (NILP (prev))
+ if (!prev)
{
BUF_MARKERS (b) = next;
/* Deleting first marker from the buffer's chain. Crash
if new first marker in chain does not say it belongs
to the same buffer, or at least that they have the same
base buffer. */
- if (!NILP (next) && b->text != XMARKER (next)->buffer->text)
+ if (next && b->text != next->buffer->text)
abort ();
}
else
- {
- omark = XMARKBIT (XMARKER (prev)->chain);
- XMARKER (prev)->chain = next;
- XSETMARKBIT (XMARKER (prev)->chain, omark);
- }
+ prev->next = next;
/* We have removed the marker from the chain;
no need to scan the rest of the chain. */
return;
{
register Lisp_Object new;
- if (! (INTEGERP (marker) || MARKERP (marker)))
- marker = wrong_type_argument (Qinteger_or_marker_p, marker);
+ CHECK_TYPE (INTEGERP (marker) || MARKERP (marker), Qinteger_or_marker_p, marker);
new = Fmake_marker ();
Fset_marker (new, marker,
DEFUN ("marker-insertion-type", Fmarker_insertion_type,
Smarker_insertion_type, 1, 1, 0,
doc: /* Return insertion type of MARKER: t if it stays after inserted text.
-nil means the marker stays before text inserted there. */)
+The value nil means the marker stays before text inserted there. */)
(marker)
register Lisp_Object marker;
{
(position)
Lisp_Object position;
{
- register Lisp_Object tail;
+ register struct Lisp_Marker *tail;
register int charno;
charno = XINT (position);
if (charno > Z)
charno = Z;
- for (tail = BUF_MARKERS (current_buffer);
- !NILP (tail);
- tail = XMARKER (tail)->chain)
- if (XMARKER (tail)->charpos == charno)
+ for (tail = BUF_MARKERS (current_buffer); tail; tail = tail->next)
+ if (tail->charpos == charno)
return Qt;
return Qnil;
}
+
+/* For debugging -- count the markers in buffer BUF. */
+
+int
+count_markers (buf)
+ struct buffer *buf;
+{
+ int total = 0;
+ struct Lisp_Marker *tail;
+
+ for (tail = BUF_MARKERS (buf); tail; tail = tail->next)
+ total++;
+
+ return total;
+}
\f
void
syms_of_marker ()
doc: /* Non-nil enables debugging checks in byte/char position conversions. */);
byte_debug_flag = 0;
}
+
+/* arch-tag: 50aa418f-cdd0-4838-b64b-94aa4b2a3b74
+ (do not change this comment) */