gdkselection.c

gtk是linux一款强大的夸平台的图形化开发工具

/* GDK - The GIMP Drawing Kit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the GTK+ Team and others 1997-1999.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
 */

#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <string.h>
#include "gdk.h"
#include "gdkprivate.h"
#include "gdkx.h"


gint
gdk_selection_owner_set (GdkWindow *owner,
			 GdkAtom    selection,
			 guint32    time,
			 gint       send_event)
{
  Display *xdisplay;
  Window xwindow;

  if (owner)
    {
      GdkWindowPrivate *private;

      private = (GdkWindowPrivate*) owner;
      if (private->destroyed)
	return FALSE;

      xdisplay = private->xdisplay;
      xwindow = private->xwindow;
    }
  else
    {
      xdisplay = gdk_display;
      xwindow = None;
    }

  XSetSelectionOwner (xdisplay, selection, xwindow, time);

  return (XGetSelectionOwner (xdisplay, selection) == xwindow);
}

GdkWindow*
gdk_selection_owner_get (GdkAtom selection)
{
  Window xwindow;

  xwindow = XGetSelectionOwner (gdk_display, selection);
  if (xwindow == None)
    return NULL;

  return gdk_window_lookup (xwindow);
}

void
gdk_selection_convert (GdkWindow *requestor,
		       GdkAtom    selection,
		       GdkAtom    target,
		       guint32    time)
{
  GdkWindowPrivate *private;

  g_return_if_fail (requestor != NULL);

  private = (GdkWindowPrivate*) requestor;
  if (private->destroyed)
    return;

  XConvertSelection (private->xdisplay, selection, target,
		     gdk_selection_property, private->xwindow, time);
}

gint
gdk_selection_property_get (GdkWindow  *requestor,
			    guchar    **data,
			    GdkAtom    *ret_type,
			    gint       *ret_format)
{
  GdkWindowPrivate *private;
  gulong nitems;
  gulong nbytes;
  gulong length;
  GdkAtom prop_type;
  gint prop_format;
  guchar *t = NULL;

  g_return_val_if_fail (requestor != NULL, 0);

  /* If retrieved chunks are typically small, (and the ICCCM says the
     should be) it would be a win to try first with a buffer of
     moderate length, to avoid two round trips to the server */

  private = (GdkWindowPrivate*) requestor;
  if (private->destroyed)
    return 0;

  t = NULL;
  XGetWindowProperty (private->xdisplay, private->xwindow,
		      gdk_selection_property, 0, 0, False,
		      AnyPropertyType, &prop_type, &prop_format,
		      &nitems, &nbytes, &t);

  if (ret_type)
    *ret_type = prop_type;
  if (ret_format)
    *ret_format = prop_format;

  if (prop_type == None)
    {
      *data = NULL;
      return 0;
    }
  
  if (t)
    {
      XFree (t);
      t = NULL;
    }

  /* Add on an extra byte to handle null termination.  X guarantees
     that t will be 1 longer than nbytes and null terminated */
  length = nbytes + 1;

  /* We can't delete the selection here, because it might be the INCR
     protocol, in which case the client has to make sure they'll be
     notified of PropertyChange events _before_ the property is deleted.
     Otherwise there's no guarantee we'll win the race ... */
  XGetWindowProperty (private->xdisplay, private->xwindow,
		      gdk_selection_property, 0, (nbytes + 3) / 4, False,
		      AnyPropertyType, &prop_type, &prop_format,
		      &nitems, &nbytes, &t);

  if (prop_type != None)
    {
      *data = g_new (guchar, length);
      memcpy (*data, t, length);
      if (t)
	XFree (t);
      return length-1;
    }
  else
    {
      *data = NULL;
      return 0;
    }
}


void
gdk_selection_send_notify (guint32  requestor,
			   GdkAtom  selection,
			   GdkAtom  target,
			   GdkAtom  property,
			   guint32  time)
{
  XSelectionEvent xevent;

  xevent.type = SelectionNotify;
  xevent.serial = 0;
  xevent.send_event = True;
  xevent.display = gdk_display;
  xevent.requestor = requestor;
  xevent.selection = selection;
  xevent.target = target;
  xevent.property = property;
  xevent.time = time;

  gdk_send_xevent (requestor, False, NoEventMask, (XEvent*) &xevent);
}

gint
gdk_text_property_to_text_list (GdkAtom encoding, gint format, 
			     guchar *text, gint length,
			     gchar ***list)
{
  XTextProperty property;
  gint count = 0;
  gint res;

  if (!list) 
    return 0;

  property.value = text;
  property.encoding = encoding;
  property.format = format;
  property.nitems = length;
  res = XmbTextPropertyToTextList (GDK_DISPLAY(), &property, list, &count);

  if (res == XNoMemory || res == XLocaleNotSupported || 
      res == XConverterNotFound)
    return 0;
  else
    return count;
}

void
gdk_free_text_list (gchar **list)
{
  g_return_if_fail (list != NULL);

  XFreeStringList (list);
}

gint
gdk_string_to_compound_text (gchar *str,
			     GdkAtom *encoding, gint *format,
			     guchar **ctext, gint *length)
{
  gint res;
  XTextProperty property;

  res = XmbTextListToTextProperty (GDK_DISPLAY(), 
				   &str, 1, XCompoundTextStyle,
                               	   &property);
  if (res != Success)
    {
      property.encoding = None;
      property.format = None;
      property.value = NULL;
      property.nitems = 0;
    }

  if (encoding)
    *encoding = property.encoding;
  if (format)
    *format = property.format;
  if (ctext)
    *ctext = property.value;
  if (length)
    *length = property.nitems;

  return res;
}

void gdk_free_compound_text (guchar *ctext)
{
  if (ctext)
    XFree (ctext);
}