539 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			539 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* gtktextmark.c - mark segments
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|  *
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|  * Copyright (c) 1994 The Regents of the University of California.
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|  * Copyright (c) 1994-1997 Sun Microsystems, Inc.
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|  * Copyright (c) 2000      Red Hat, Inc.
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|  * Tk -> Gtk port by Havoc Pennington <hp@redhat.com>
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|  *
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|  * This software is copyrighted by the Regents of the University of
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|  * California, Sun Microsystems, Inc., and other parties.  The
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|  * following terms apply to all files associated with the software
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|  * unless explicitly disclaimed in individual files.
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|  *
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|  * The authors hereby grant permission to use, copy, modify,
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|  * distribute, and license this software and its documentation for any
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|  * purpose, provided that existing copyright notices are retained in
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|  * all copies and that this notice is included verbatim in any
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|  * distributions. No written agreement, license, or royalty fee is
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|  * required for any of the authorized uses.  Modifications to this
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|  * software may be copyrighted by their authors and need not follow
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|  * the licensing terms described here, provided that the new terms are
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|  * clearly indicated on the first page of each file where they apply.
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|  *
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|  * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY
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|  * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
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|  * DAMAGES ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION,
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|  * OR ANY DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED
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|  * OF THE POSSIBILITY OF SUCH DAMAGE.
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|  *
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|  * THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
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|  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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|  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND
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|  * NON-INFRINGEMENT.  THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS,
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|  * AND THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE
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|  * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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|  *
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|  * GOVERNMENT USE: If you are acquiring this software on behalf of the
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|  * U.S. government, the Government shall have only "Restricted Rights"
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|  * in the software and related documentation as defined in the Federal
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|  * Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2).  If you
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|  * are acquiring the software on behalf of the Department of Defense,
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|  * the software shall be classified as "Commercial Computer Software"
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|  * and the Government shall have only "Restricted Rights" as defined
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|  * in Clause 252.227-7013 (c) (1) of DFARs.  Notwithstanding the
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|  * foregoing, the authors grant the U.S. Government and others acting
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|  * in its behalf permission to use and distribute the software in
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|  * accordance with the terms specified in this license.
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|  *
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|  */
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| 
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| #define GTK_TEXT_USE_INTERNAL_UNSUPPORTED_API
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| #include "config.h"
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| #include "gtktextbtree.h"
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| #include "gtkprivate.h"
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| #include "gtkintl.h"
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| 
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| 
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| /**
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|  * SECTION:gtktextmark
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|  * @Short_description: A position in the buffer preserved across buffer modifications
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|  * @Title: GtkTextMark
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|  *
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|  * You may wish to begin by reading the
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|  * [text widget conceptual overview](TextWidget.html)
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|  * which gives an overview of all the objects and data
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|  * types related to the text widget and how they work together.
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|  *
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|  * A #GtkTextMark is like a bookmark in a text buffer; it preserves a position in
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|  * the text. You can convert the mark to an iterator using
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|  * gtk_text_buffer_get_iter_at_mark(). Unlike iterators, marks remain valid across
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|  * buffer mutations, because their behavior is defined when text is inserted or
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|  * deleted. When text containing a mark is deleted, the mark remains in the
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|  * position originally occupied by the deleted text. When text is inserted at a
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|  * mark, a mark with “left gravity” will be moved to the
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|  * beginning of the newly-inserted text, and a mark with “right
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|  * gravity” will be moved to the end.
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|  *
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|  * Note that “left” and “right” here refer to logical direction (left
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|  * is the toward the start of the buffer); in some languages such as
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|  * Hebrew the logically-leftmost text is not actually on the left when
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|  * displayed.
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|  *
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|  * Marks are reference counted, but the reference count only controls the validity
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|  * of the memory; marks can be deleted from the buffer at any time with
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|  * gtk_text_buffer_delete_mark(). Once deleted from the buffer, a mark is
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|  * essentially useless.
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|  *
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|  * Marks optionally have names; these can be convenient to avoid passing the
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|  * #GtkTextMark object around.
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|  *
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|  * Marks are typically created using the gtk_text_buffer_create_mark() function.
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|  */
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| 
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| /*
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|  * Macro that determines the size of a mark segment:
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|  */
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| #define MSEG_SIZE ((unsigned) (G_STRUCT_OFFSET (GtkTextLineSegment, body) \
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|         + sizeof (GtkTextMarkBody)))
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| 
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| static void gtk_text_mark_set_property (GObject         *object,
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| 				        guint            prop_id,
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| 					const GValue    *value,
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| 					GParamSpec      *pspec);
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| static void gtk_text_mark_get_property (GObject         *object,
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| 					guint            prop_id,
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| 					GValue          *value,
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| 					GParamSpec      *pspec);
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| static void gtk_text_mark_finalize     (GObject         *object);
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| 
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| static GtkTextLineSegment *gtk_mark_segment_new (GtkTextMark *mark_obj);
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| 
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| G_DEFINE_TYPE (GtkTextMark, gtk_text_mark, G_TYPE_OBJECT)
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| 
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| enum {
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|   PROP_0,
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|   PROP_NAME,
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|   PROP_LEFT_GRAVITY
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| };
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| 
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| static void
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| gtk_text_mark_class_init (GtkTextMarkClass *klass)
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| {
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|   GObjectClass *object_class = G_OBJECT_CLASS (klass);
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| 
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|   object_class->finalize = gtk_text_mark_finalize;
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|   object_class->set_property = gtk_text_mark_set_property;
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|   object_class->get_property = gtk_text_mark_get_property;
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| 
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|   /**
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|    * GtkTextMark:name:
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|    *
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|    * The name of the mark or %NULL if the mark is anonymous.
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|    */
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|   g_object_class_install_property (object_class,
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|                                    PROP_NAME,
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|                                    g_param_spec_string ("name",
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|                                                         P_("Name"),
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|                                                         P_("Mark name"),
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|                                                         NULL,
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|                                                         GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
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| 
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|   /**
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|    * GtkTextMark:left-gravity:
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|    *
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|    * Whether the mark has left gravity. When text is inserted at the mark’s
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|    * current location, if the mark has left gravity it will be moved
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|    * to the left of the newly-inserted text, otherwise to the right.
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|    */
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|   g_object_class_install_property (object_class,
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|                                    PROP_LEFT_GRAVITY,
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|                                    g_param_spec_boolean ("left-gravity",
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|                                                          P_("Left gravity"),
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|                                                          P_("Whether the mark has left gravity"),
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|                                                          FALSE,
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|                                                          GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
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| }
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| 
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| static void
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| gtk_text_mark_init (GtkTextMark *mark)
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| {
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|   mark->segment = gtk_mark_segment_new (mark);
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| }
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| 
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| static void
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| gtk_text_mark_finalize (GObject *obj)
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| {
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|   GtkTextMark *mark;
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|   GtkTextLineSegment *seg;
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| 
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|   mark = GTK_TEXT_MARK (obj);
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| 
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|   seg = mark->segment;
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| 
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|   if (seg)
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|     {
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|       if (seg->body.mark.tree != NULL)
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|         g_warning ("GtkTextMark being finalized while still in the buffer; "
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|                    "someone removed a reference they didn't own! Crash "
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|                    "impending");
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| 
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|       g_free (seg->body.mark.name);
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|       g_slice_free1 (MSEG_SIZE, seg);
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| 
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|       mark->segment = NULL;
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|     }
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| 
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|   /* chain parent_class' handler */
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|   G_OBJECT_CLASS (gtk_text_mark_parent_class)->finalize (obj);
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| }
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| 
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| static void
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| gtk_text_mark_set_property (GObject      *object,
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| 			    guint         prop_id,
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| 			    const GValue *value,
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| 			    GParamSpec   *pspec)
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| {
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|   gchar *tmp;
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|   GtkTextMark *mark = GTK_TEXT_MARK (object);
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|   GtkTextLineSegment *seg = mark->segment;
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| 
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|   switch (prop_id)
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|     {
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|     case PROP_NAME:
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|       tmp = seg->body.mark.name;
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|       seg->body.mark.name = g_value_dup_string (value);
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|       g_free (tmp);
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|       break;
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| 
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|     case PROP_LEFT_GRAVITY:
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|       if (g_value_get_boolean (value))
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| 	seg->type = >k_text_left_mark_type;
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|       else
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| 	seg->type = >k_text_right_mark_type;
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|       break;
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| 
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|     default:
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|       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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|     }
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| }
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| 
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| static void
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| gtk_text_mark_get_property (GObject    *object,
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| 			    guint       prop_id,
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| 			    GValue     *value,
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| 			    GParamSpec *pspec)
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| {
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|   GtkTextMark *mark = GTK_TEXT_MARK (object);
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| 
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|   switch (prop_id)
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|     {
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|     case PROP_NAME:
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|       g_value_set_string (value, gtk_text_mark_get_name (mark));
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|       break;
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| 
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|     case PROP_LEFT_GRAVITY:
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|       g_value_set_boolean (value, gtk_text_mark_get_left_gravity (mark));
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|       break;
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| 
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|     default:
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|       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
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|     }
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| }
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| 
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| /**
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|  * gtk_text_mark_new:
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|  * @name: (allow-none): mark name or %NULL
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|  * @left_gravity: whether the mark should have left gravity
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|  *
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|  * Creates a text mark. Add it to a buffer using gtk_text_buffer_add_mark().
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|  * If @name is %NULL, the mark is anonymous; otherwise, the mark can be 
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|  * retrieved by name using gtk_text_buffer_get_mark(). If a mark has left 
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|  * gravity, and text is inserted at the mark’s current location, the mark 
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|  * will be moved to the left of the newly-inserted text. If the mark has 
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|  * right gravity (@left_gravity = %FALSE), the mark will end up on the 
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|  * right of newly-inserted text. The standard left-to-right cursor is a 
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|  * mark with right gravity (when you type, the cursor stays on the right
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|  * side of the text you’re typing).
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|  *
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|  * Returns: new #GtkTextMark
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|  *
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|  * Since: 2.12
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|  **/
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| GtkTextMark *
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| gtk_text_mark_new (const gchar *name,
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| 		   gboolean     left_gravity)
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| {
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|   return g_object_new (GTK_TYPE_TEXT_MARK,
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| 		       "name", name,
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| 		       "left-gravity", left_gravity,
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| 		       NULL);
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| }
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| 
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| /**
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|  * gtk_text_mark_get_visible:
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|  * @mark: a #GtkTextMark
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|  * 
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|  * Returns %TRUE if the mark is visible (i.e. a cursor is displayed
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|  * for it).
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|  * 
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|  * Returns: %TRUE if visible
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|  **/
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| gboolean
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| gtk_text_mark_get_visible (GtkTextMark *mark)
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| {
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|   GtkTextLineSegment *seg;
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| 
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|   seg = mark->segment;
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| 
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|   return seg->body.mark.visible;
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| }
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| 
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| /**
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|  * gtk_text_mark_get_name:
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|  * @mark: a #GtkTextMark
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|  * 
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|  * Returns the mark name; returns NULL for anonymous marks.
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|  * 
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|  * Returns: (nullable): mark name
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|  **/
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| const char *
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| gtk_text_mark_get_name (GtkTextMark *mark)
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| {
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|   GtkTextLineSegment *seg;
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| 
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|   seg = mark->segment;
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| 
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|   return seg->body.mark.name;
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| }
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| 
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| /**
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|  * gtk_text_mark_get_deleted:
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|  * @mark: a #GtkTextMark
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|  * 
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|  * Returns %TRUE if the mark has been removed from its buffer
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|  * with gtk_text_buffer_delete_mark(). See gtk_text_buffer_add_mark()
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|  * for a way to add it to a buffer again.
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|  * 
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|  * Returns: whether the mark is deleted
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|  **/
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| gboolean
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| gtk_text_mark_get_deleted (GtkTextMark *mark)
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| {
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|   GtkTextLineSegment *seg;
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| 
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|   g_return_val_if_fail (GTK_IS_TEXT_MARK (mark), FALSE);
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| 
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|   seg = mark->segment;
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| 
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|   if (seg == NULL)
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|     return TRUE;
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| 
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|   return seg->body.mark.tree == NULL;
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| }
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| 
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| /**
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|  * gtk_text_mark_get_buffer:
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|  * @mark: a #GtkTextMark
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|  * 
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|  * Gets the buffer this mark is located inside,
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|  * or %NULL if the mark is deleted.
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|  *
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|  * Returns: (transfer none): the mark’s #GtkTextBuffer
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|  **/
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| GtkTextBuffer*
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| gtk_text_mark_get_buffer (GtkTextMark *mark)
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| {
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|   GtkTextLineSegment *seg;
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| 
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|   g_return_val_if_fail (GTK_IS_TEXT_MARK (mark), NULL);
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| 
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|   seg = mark->segment;
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| 
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|   if (seg->body.mark.tree == NULL)
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|     return NULL;
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|   else
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|     return _gtk_text_btree_get_buffer (seg->body.mark.tree);
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| }
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| 
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| /**
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|  * gtk_text_mark_get_left_gravity:
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|  * @mark: a #GtkTextMark
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|  * 
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|  * Determines whether the mark has left gravity.
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|  * 
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|  * Returns: %TRUE if the mark has left gravity, %FALSE otherwise
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|  **/
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| gboolean
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| gtk_text_mark_get_left_gravity (GtkTextMark *mark)
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| {
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|   GtkTextLineSegment *seg;
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| 
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|   g_return_val_if_fail (GTK_IS_TEXT_MARK (mark), FALSE);
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|   
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|   seg = mark->segment;
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| 
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|   return seg->type == >k_text_left_mark_type;
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| }
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| 
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| static GtkTextLineSegment *
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| gtk_mark_segment_new (GtkTextMark *mark_obj)
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| {
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|   GtkTextLineSegment *mark;
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| 
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|   mark = g_slice_alloc0 (MSEG_SIZE);
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|   mark->body.mark.name = NULL;
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|   mark->type = >k_text_right_mark_type;
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| 
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|   mark->byte_count = 0;
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|   mark->char_count = 0;
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| 
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|   mark->body.mark.obj = mark_obj;
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|   mark_obj->segment = mark;
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| 
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|   mark->body.mark.tree = NULL;
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|   mark->body.mark.line = NULL;
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|   mark->next = NULL;
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| 
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|   mark->body.mark.visible = FALSE;
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|   mark->body.mark.not_deleteable = FALSE;
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| 
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|   return mark;
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| }
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| 
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| void
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| _gtk_mark_segment_set_tree (GtkTextLineSegment *mark,
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| 			    GtkTextBTree       *tree)
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| {
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|   g_assert (mark->body.mark.tree == NULL);
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|   g_assert (mark->body.mark.obj != NULL);
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| 
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|   mark->byte_count = 0;
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|   mark->char_count = 0;
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| 
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|   mark->body.mark.tree = tree;
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|   mark->body.mark.line = NULL;
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|   mark->next = NULL;
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| 
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|   mark->body.mark.not_deleteable = FALSE;
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| }
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| 
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| static int                 mark_segment_delete_func  (GtkTextLineSegment *segPtr,
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|                                                       GtkTextLine        *line,
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|                                                       int                 treeGone);
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| static GtkTextLineSegment *mark_segment_cleanup_func (GtkTextLineSegment *segPtr,
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|                                                       GtkTextLine        *line);
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| static void                mark_segment_check_func   (GtkTextLineSegment *segPtr,
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|                                                       GtkTextLine        *line);
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| 
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| 
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| /*
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|  * The following structures declare the "mark" segment types.
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|  * There are actually two types for marks, one with left gravity
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|  * and one with right gravity.  They are identical except for
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|  * their gravity property.
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|  */
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| 
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| const GtkTextLineSegmentClass gtk_text_right_mark_type = {
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|   "mark",                                               /* name */
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|   FALSE,                                                /* leftGravity */
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|   NULL,                                         /* splitFunc */
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|   mark_segment_delete_func,                             /* deleteFunc */
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|   mark_segment_cleanup_func,                            /* cleanupFunc */
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|   NULL,                                         /* lineChangeFunc */
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|   mark_segment_check_func                               /* checkFunc */
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| };
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| 
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| const GtkTextLineSegmentClass gtk_text_left_mark_type = {
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|   "mark",                                               /* name */
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|   TRUE,                                         /* leftGravity */
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|   NULL,                                         /* splitFunc */
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|   mark_segment_delete_func,                             /* deleteFunc */
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|   mark_segment_cleanup_func,                            /* cleanupFunc */
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|   NULL,                                         /* lineChangeFunc */
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|   mark_segment_check_func                               /* checkFunc */
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| };
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| 
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| /*
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|  *--------------------------------------------------------------
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|  *
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|  * mark_segment_delete_func --
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|  *
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|  *      This procedure is invoked by the text B-tree code whenever
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|  *      a mark lies in a range of characters being deleted.
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|  *
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|  * Results:
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|  *      Returns 1 to indicate that deletion has been rejected,
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|  *      or 0 otherwise
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|  *
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|  * Side effects:
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|  *      Frees mark if tree is going away
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|  *
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|  *--------------------------------------------------------------
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|  */
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| 
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| static gboolean
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| mark_segment_delete_func (GtkTextLineSegment *seg,
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|                           GtkTextLine        *line,
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|                           gboolean            tree_gone)
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| {
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|   if (tree_gone)
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|     {
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|       _gtk_text_btree_release_mark_segment (seg->body.mark.tree, seg);
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|       return FALSE;
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|     }
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|   else
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|     return TRUE;
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| }
 | ||
| 
 | ||
| /*
 | ||
|  *--------------------------------------------------------------
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|  *
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|  * mark_segment_cleanup_func --
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|  *
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|  *      This procedure is invoked by the B-tree code whenever a
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|  *      mark segment is moved from one line to another.
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|  *
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|  * Results:
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|  *      None.
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|  *
 | ||
|  * Side effects:
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|  *      The line field of the segment gets updated.
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|  *
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|  *--------------------------------------------------------------
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|  */
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| 
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| static GtkTextLineSegment *
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| mark_segment_cleanup_func (GtkTextLineSegment *seg,
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|                            GtkTextLine        *line)
 | ||
| {
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|   /* not sure why Tk did this here and not in LineChangeFunc */
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|   seg->body.mark.line = line;
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|   return seg;
 | ||
| }
 | ||
| 
 | ||
| /*
 | ||
|  *--------------------------------------------------------------
 | ||
|  *
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|  * mark_segment_check_func --
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|  *
 | ||
|  *      This procedure is invoked by the B-tree code to perform
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|  *      consistency checks on mark segments.
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|  *
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|  * Results:
 | ||
|  *      None.
 | ||
|  *
 | ||
|  * Side effects:
 | ||
|  *      The procedure panics if it detects anything wrong with
 | ||
|  *      the mark.
 | ||
|  *
 | ||
|  *--------------------------------------------------------------
 | ||
|  */
 | ||
| 
 | ||
| static void
 | ||
| mark_segment_check_func (GtkTextLineSegment *seg,
 | ||
|                          GtkTextLine        *line)
 | ||
| {
 | ||
|   if (seg->body.mark.line != line)
 | ||
|     g_error ("mark_segment_check_func: seg->body.mark.line bogus");
 | ||
| }
 | 
