Add a --screen option for setting the default screen. (Based on a patch

Thu Oct 31 12:40:39 2002  Owen Taylor  <otaylor@redhat.com>

        * gdk/gdk.[ch] gdk/gdkglobals.c gdk/gdkinternals.h
        gdk/{x11,win32,linux-fb}/gdkscreen-{x11,win32,linux-fb}.c:
        Add a --screen option for setting the default screen.
        (Based on a patch from Balamurali Viswanathan, #81145)

        * gdk/gdk.c gdkdisplay.h gtk/gtkmain.c: Add
        gdk_display_open_default_libgtk_only(), so gtk_init_check()
        and gdk_init_check() can share the same behavior w.r.t.
        --screen.

        * gdk/gdk.[ch]: Make gdk_get_display_arg_name() G_CONST_RETURN.

        * gdk/x11/gdkselection-x11.c (gdk_selection_property_get):
        Suppress a spurious warning.

        * tests/testgtkrc: Remove someleft-over commented out
        includes that could be confusing.

10 files changed, 122 insertions, 31 deletions

diff --git a/gdk/gdk.c b/gdk/gdk.c
index 1eee68bbb5..f1712e876a 100644
--- a/gdk/gdk.c
+++ b/gdk/gdk.c
@@ -239,6 +239,7 @@ static GdkArgDesc gdk_args[] = {
   { "class" ,       GDK_ARG_CALLBACK, NULL, gdk_arg_class_cb                   },
   { "name",         GDK_ARG_CALLBACK, NULL, gdk_arg_name_cb                    },
   { "display",      GDK_ARG_STRING,   &_gdk_display_name,     (GdkArgFunc)NULL },
+  { "screen",       GDK_ARG_INT,      &_gdk_screen_number,    (GdkArgFunc)NULL },
 
 #ifdef G_ENABLE_DEBUG
   { "gdk-debug",    GDK_ARG_CALLBACK, NULL, gdk_arg_debug_cb    },
@@ -355,11 +356,60 @@ gdk_parse_args (int    *argc,
  * to gdk_init() or gdk_parse_args(), if any.
  *
  * Returns: the display name, if specified explicitely, otherwise %NULL
+ *   this string is owned by GTK+ and must not be modified or freed.
  */
-gchar *
+G_CONST_RETURN gchar *
 gdk_get_display_arg_name (void)
 {
-  return _gdk_display_name;
+  if (!_gdk_display_arg_name)
+    {
+      if (_gdk_screen_number >= 0)
+	_gdk_display_arg_name = _gdk_windowing_substitute_screen_number (_gdk_display_name, _gdk_screen_number);
+      else
+	_gdk_display_arg_name = g_strdup (_gdk_display_name);
+   }
+
+   return _gdk_display_arg_name;
+}
+
+/**
+ * gdk_display_open_default_libgtk_only:
+ * 
+ * Opens the default display specified by command line arguments or
+ * environment variables, sets it as the default display, and returns
+ * it.  gdk_parse_args must have been called first. If the default
+ * display has previously been set, simply returns that. An internal
+ * function that should not be used by applications.
+ * 
+ * Return value: the default display, if it could be opened,
+ *   otherwise %NULL.
+ **/
+GdkDisplay *
+gdk_display_open_default_libgtk_only (void)
+{
+  GdkDisplay *display;
+
+  g_return_if_fail (gdk_initialized);
+  
+  display = gdk_display_get_default ();
+  if (display)
+    return display;
+
+  display = gdk_display_open (gdk_get_display_arg_name ());
+
+  if (!display && _gdk_screen_number >= 0)
+    {
+      g_free (_gdk_display_arg_name);
+      _gdk_display_arg_name = g_strdup (_gdk_display_name);
+      
+      display = gdk_display_open (_gdk_display_name);
+    }
+  
+  if (display)
+    gdk_display_manager_set_default_display (gdk_display_manager_get (),
+					     display);
+  
+  return display;
 }
 
 /*
@@ -392,19 +442,7 @@ gdk_init_check (int    *argc,
   
   gdk_parse_args (argc, argv);
 
-  if (gdk_display_get_default ())
-    return TRUE;
-    
-  display = gdk_display_open (_gdk_display_name);
-
-  if (display)
-    {
-      gdk_display_manager_set_default_display (gdk_display_manager_get (),
-					       display);
-      return TRUE;
-    }
-  else
-    return FALSE;
+  return gdk_display_open_default_libgtk_only () != NULL;
 }
 
 void
diff --git a/gdk/gdk.h b/gdk/gdk.h
index 44b7391e93..811c484935 100644
--- a/gdk/gdk.h
+++ b/gdk/gdk.h
@@ -85,8 +85,8 @@ void	  gdk_set_use_xshm		(gboolean	 use_xshm);
 gboolean  gdk_get_use_xshm		(void);
 #endif /* GDK_DISABLE_DEPRECATED */
 
-gchar*	  gdk_get_display		(void);
-gchar*	  gdk_get_display_arg_name	(void);
+gchar*	                  gdk_get_display		(void);
+G_CONST_RETURN gchar*	  gdk_get_display_arg_name	(void);
 
 #ifndef GDK_DISABLE_DEPRECATED
 gint gdk_input_add_full	  (gint		     source,
diff --git a/gdk/gdkdisplay.h b/gdk/gdkdisplay.h
index a7f7234924..5e2485f5fa 100644
--- a/gdk/gdkdisplay.h
+++ b/gdk/gdkdisplay.h
@@ -146,6 +146,8 @@ GdkWindow *      gdk_display_get_window_at_pointer (GdkDisplay             *disp
 GdkDisplayPointerHooks *gdk_display_set_pointer_hooks (GdkDisplay                   *display,
 						       const GdkDisplayPointerHooks *new_hooks);
 
+GdkDisplay *gdk_display_open_default_libgtk_only (void);
+
 G_END_DECLS
 
 #endif				/* __GDK_DISPLAY_H__ */
diff --git a/gdk/gdkglobals.c b/gdk/gdkglobals.c
index 052938952a..a4ec657457 100644
--- a/gdk/gdkglobals.c
+++ b/gdk/gdkglobals.c
@@ -35,6 +35,8 @@ gint                _gdk_error_code = 0;
 gint                _gdk_error_warnings = TRUE;
 GList              *_gdk_default_filters = NULL;
 gchar              *_gdk_display_name = NULL;
+gint                _gdk_screen_number = -1;
+gchar              *_gdk_display_arg_name = NULL;
 
 GSList             *_gdk_displays = NULL;
 
diff --git a/gdk/gdkinternals.h b/gdk/gdkinternals.h
index 3805c15504..d1e3e857e4 100644
--- a/gdk/gdkinternals.h
+++ b/gdk/gdkinternals.h
@@ -166,6 +166,8 @@ extern GDestroyNotify _gdk_event_notify;
 
 extern GSList    *_gdk_displays;
 extern gchar     *_gdk_display_name;
+extern gint       _gdk_screen_number;
+extern gchar     *_gdk_display_arg_name;
 
 void      _gdk_events_queue  (GdkDisplay *display);
 GdkEvent* _gdk_event_unqueue (GdkDisplay *display);
@@ -236,6 +238,9 @@ void     _gdk_windowing_init                    (gint       *argc,
                                                  gchar    ***argv);
 void     _gdk_windowing_set_default_display     (GdkDisplay *display);
 
+gchar *_gdk_windowing_substitute_screen_number (const gchar *display_name,
+					        gint         screen_number);
+
 void     _gdk_windowing_window_get_offsets      (GdkWindow  *window,
 						 gint       *x_offset,
 						 gint       *y_offset);
diff --git a/gdk/gdkscreen.h b/gdk/gdkscreen.h
index 2e2b199286..6e2241aa5b 100644
--- a/gdk/gdkscreen.h
+++ b/gdk/gdkscreen.h
@@ -73,7 +73,6 @@ GList *      gdk_screen_list_visuals          (GdkScreen   *screen);
 GList *      gdk_screen_get_toplevel_windows  (GdkScreen   *screen);
 gchar *      gdk_screen_make_display_name     (GdkScreen   *screen);
 
-
 gint          gdk_screen_get_n_monitors        (GdkScreen *screen);
 void          gdk_screen_get_monitor_geometry  (GdkScreen *screen,
 						gint       monitor_num,
diff --git a/gdk/linux-fb/gdkscreen-fb.c b/gdk/linux-fb/gdkscreen-fb.c
index cb8e8f4fd7..a5914734b3 100644
--- a/gdk/linux-fb/gdkscreen-fb.c
+++ b/gdk/linux-fb/gdkscreen-fb.c
@@ -79,6 +79,13 @@ gdk_screen_get_number (GdkScreen *screen)
   return 0;
 }
 
+gchar * 
+_gdk_windowing_substitute_screen_number (gchar *display_name,
+					 int    screen_number)
+{
+  return g_strdup (display_name);
+}
+
 gchar *
 gdk_screen_make_display_name (GdkScreen *screen)
 {
diff --git a/gdk/win32/gdkscreen-win32.c b/gdk/win32/gdkscreen-win32.c
index 084b6c88e9..c5455bd3b9 100644
--- a/gdk/win32/gdkscreen-win32.c
+++ b/gdk/win32/gdkscreen-win32.c
@@ -81,6 +81,13 @@ gdk_screen_get_number (GdkScreen *screen)
   return 0;
 }
 
+gchar * 
+_gdk_windowing_substitute_screen_number (gchar *display_name,
+					 int    screen_number)
+{
+  return g_strdup (display_name);
+}
+
 gchar *
 gdk_screen_make_display_name (GdkScreen *screen)
 {
diff --git a/gdk/x11/gdkscreen-x11.c b/gdk/x11/gdkscreen-x11.c
index 98a60a7fd0..dd030103ff 100644
--- a/gdk/x11/gdkscreen-x11.c
+++ b/gdk/x11/gdkscreen-x11.c
@@ -552,6 +552,45 @@ _gdk_x11_screen_window_manager_changed (GdkScreen *screen)
 }
 
 /**
+ * _gdk_windowing_substitute_screen_number:
+ * @display_name : The name of a display, in the form used by 
+ *                 gdk_display_open (). If %NULL a default value
+ *                 will be used. On X11, this is derived from the DISPLAY
+ *                 environment variable.
+ * @screen_number : The number of a screen within the display
+ *                  referred to by @display_name.
+ *
+ * Modifies a @display_name to make @screen_number the default
+ * screen when the display is opened.
+ *
+ * Return value: a newly allocated string holding the resulting
+ *   display name. Free with g_free().
+ */
+gchar * 
+_gdk_windowing_substitute_screen_number (const gchar *display_name,
+					 gint         screen_number)
+{
+  GString *str;
+  gchar   *p;
+
+  if (!display_name)
+    display_name = getenv ("DISPLAY");
+
+  if (!display_name)
+    return NULL;
+
+  str = g_string_new (display_name);
+
+  p = strrchr (str->str, '.');
+  if (p && p >	strchr (str->str, ':'))
+    g_string_truncate (str, p - str->str);
+
+  g_string_append_printf (str, ".%d", screen_number);
+
+  return g_string_free (str, FALSE);
+}
+
+/**
  * gdk_screen_make_display_name:
  * @screen: a #GdkScreen
  * 
@@ -563,20 +602,12 @@ _gdk_x11_screen_window_manager_changed (GdkScreen *screen)
 gchar *
 gdk_screen_make_display_name (GdkScreen *screen)
 {
-  GString     *str;
   const gchar *old_display;
-  gchar       *p;
-
-  old_display = gdk_display_get_name (gdk_screen_get_display (screen));
 
-  str = g_string_new (old_display);
-        
-  p = strrchr (str->str, '.');
-  if (p && p >  strchr (str->str, ':'))
-    g_string_truncate (str, p - str->str);
+  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);
 
-  g_string_append_printf (str, ".%d", gdk_screen_get_number (screen));
+  old_display = gdk_display_get_name (gdk_screen_get_display (screen));
 
-  return g_string_free (str, FALSE);
+  return _gdk_windowing_substitute_screen_number (old_display, 
+						  gdk_screen_get_number (screen));
 }
-
diff --git a/gdk/x11/gdkselection-x11.c b/gdk/x11/gdkselection-x11.c
index 927dc61e49..7e87980b64 100644
--- a/gdk/x11/gdkselection-x11.c
+++ b/gdk/x11/gdkselection-x11.c
@@ -261,7 +261,7 @@ gdk_selection_property_get (GdkWindow  *requestor,
 {
   gulong nitems;
   gulong nbytes;
-  gulong length;
+  gulong length = 0;		/* Quiet GCC */
   Atom prop_type;
   gint prop_format;
   guchar *t = NULL;