Bug 549711 – Race condition when loading gdk-pixbuf image modules

2008-09-03  Matthias Clasen  <mclasen@redhat.com>

        Bug 549711 – Race condition when loading gdk-pixbuf image modules

        * gdk-pixbuf-io.c: Fix a race condition in module loading,
        spotted by Chris Lord.

svn path=/trunk/; revision=21268

diff --git a/gdk-pixbuf/ChangeLog b/gdk-pixbuf/ChangeLog
index f0fa4083550542477156c02020c318f53d85719e..60101479afda8fbc1166f5c5fde3338e028dc720 100644 (file)
--- a/gdk-pixbuf/ChangeLog
+++ b/gdk-pixbuf/ChangeLog
@@ -1,3 +1,10 @@
+2008-09-03  Matthias Clasen  <mclasen@redhat.com>
+
+       Bug 549711 – Race condition when loading gdk-pixbuf image modules
+
+       * gdk-pixbuf-io.c: Fix a race condition in module loading,
+       spotted by Chris Lord.
+
 2008-08-27  Matthias Clasen  <mclasen@redhat.com>
 
        Bug 549322 – Typo in gdk_pixbuf_save_to_buffer docs

diff --git a/gdk-pixbuf/gdk-pixbuf-io.c b/gdk-pixbuf/gdk-pixbuf-io.c
index a262c03ab256601809b1c14704a25c5ed1ac63d3..6b248738b6d35b45725d164555aa05df1c8b6bb0 100644 (file)
--- a/gdk-pixbuf/gdk-pixbuf-io.c
+++ b/gdk-pixbuf/gdk-pixbuf-io.c
@@ -626,6 +626,20 @@ _gdk_pixbuf_load_module (GdkPixbufModule *image_module,
        GdkPixbufModuleFillInfoFunc fill_info = NULL;
         GdkPixbufModuleFillVtableFunc fill_vtable = NULL;
 
+       /* be extra careful, maybe the module initializes
+        * the thread system
+        */
+       if (g_threads_got_initialized) {
+               G_LOCK (init_lock);
+               locked = TRUE;
+       }
+
+       if (image_module->module != NULL) {
+               if (locked)
+                       G_UNLOCK (init_lock);
+               return TRUE;
+       }
+
 #define try_module(format,id)                                          \
        if (fill_info == NULL &&                                        \
            strcmp (image_module->module_name, #format) == 0) {         \
@@ -701,34 +715,26 @@ _gdk_pixbuf_load_module (GdkPixbufModule *image_module,
                image_module->info = g_new0 (GdkPixbufFormat, 1);
                (* fill_info) (image_module->info);
 
-                return TRUE;
+                ret = TRUE;
        }
-
+       else {
 #ifdef USE_GMODULE
+               ret = _gdk_pixbuf_load_module_unlocked (image_module, error);
+#else
+               g_set_error (error,
+                            GDK_PIXBUF_ERROR,
+                            GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
+                            _("Image type '%s' is not supported",
+                            image_module->module_name);
 
-       /* be extra careful, maybe the module initializes
-        * the thread system
-        */
-       if (g_threads_got_initialized)
-       {
-               G_LOCK (init_lock);
-               locked = TRUE;
+               ret = FALSE;
+#endif
        }
-       ret = _gdk_pixbuf_load_module_unlocked (image_module, error);
+
        if (locked)
                G_UNLOCK (init_lock);
-       return ret;
-
-#else
-       g_set_error (error,
-                    GDK_PIXBUF_ERROR,
-                    GDK_PIXBUF_ERROR_UNKNOWN_TYPE,
-                    _("Image type '%s' is not supported"),
-                    image_module->module_name);
-
-       return FALSE;
 
-#endif
+       return ret;
 }
 
 \f
@@ -967,12 +973,11 @@ gdk_pixbuf_new_from_file (const char *filename,
                 return NULL;
         }
 
-       if (image_module->module == NULL)
-                if (!_gdk_pixbuf_load_module (image_module, error)) {
-                       g_free (display_name);
-                        fclose (f);
-                        return NULL;
-                }
+        if (!_gdk_pixbuf_load_module (image_module, error)) {
+               g_free (display_name);
+               fclose (f);
+               return NULL;
+        }
 
        fseek (f, 0, SEEK_SET);
        pixbuf = _gdk_pixbuf_generic_image_load (image_module, f, error);
@@ -1561,12 +1566,10 @@ gdk_pixbuf_new_from_xpm_data (const char **data)
                return NULL;
        }
 
-       if (xpm_module->module == NULL) {
-                if (!_gdk_pixbuf_load_module (xpm_module, &error)) {
-                        g_warning ("Error loading XPM image loader: %s", error->message);
-                        g_error_free (error);
-                        return NULL;
-                }
+        if (!_gdk_pixbuf_load_module (xpm_module, &error)) {
+                g_warning ("Error loading XPM image loader: %s", error->message);
+                g_error_free (error);
+                return NULL;
         }
 
        locked = _gdk_pixbuf_lock (xpm_module);
@@ -1659,9 +1662,8 @@ gdk_pixbuf_real_save (GdkPixbuf     *pixbuf,
        if (image_module == NULL)
                return FALSE;
        
-       if (image_module->module == NULL)
-               if (!_gdk_pixbuf_load_module (image_module, error))
-                       return FALSE;
+       if (!_gdk_pixbuf_load_module (image_module, error))
+               return FALSE;
 
        locked = _gdk_pixbuf_lock (image_module);
 
@@ -1790,9 +1792,8 @@ gdk_pixbuf_real_save_to_callback (GdkPixbuf         *pixbuf,
        if (image_module == NULL)
                return FALSE;
        
-       if (image_module->module == NULL)
-               if (!_gdk_pixbuf_load_module (image_module, error))
-                       return FALSE;
+       if (!_gdk_pixbuf_load_module (image_module, error))
+               return FALSE;
 
        locked = _gdk_pixbuf_lock (image_module);