Add two functions to check and change the SIGSEGV behaviour when loading plugins.

Original commit message from CVS:
* docs/gst/gstreamer-sections.txt:
* gst/gst.c: (gst_segtrap_is_enabled), (gst_segtrap_set_enabled):
* gst/gst.h:
* gst/gstplugin.c: (_gst_plugin_fault_handler_restore):
Add two functions to check and change the SIGSEGV behaviour
when loading plugins.
Don't mess with the SIGSEGV handler when we were told not to.
Fixes #347794.
API: gst_segtrap_is_enabled
API: gst_segtrap_set_enabled

ChangeLog

@@ -1,3 +1,16 @@
+2006-07-17  Wim Taymans  <wim@fluendo.com>
+
+	* docs/gst/gstreamer-sections.txt:
+	* gst/gst.c: (gst_segtrap_is_enabled), (gst_segtrap_set_enabled):
+	* gst/gst.h:
+	* gst/gstplugin.c: (_gst_plugin_fault_handler_restore):
+	Add two functions to check and change the SIGSEGV behaviour
+	when loading plugins.
+	Don't mess with the SIGSEGV handler when we were told not to.
+	Fixes #347794.
+	API: gst_segtrap_is_enabled
+	API: gst_segtrap_set_enabled
+
 2006-07-14  Wim Taymans  <wim@fluendo.com>
 
 	* libs/gst/base/gstbasesrc.c: (gst_base_src_update_length):

docs/gst/gstreamer-sections.txt

@@ -25,6 +25,8 @@ gst_init_get_option_group
 gst_deinit
 gst_version
 gst_version_string
+gst_segtrap_is_enabled
+gst_segtrap_set_enabled
 <SUBSECTION Private>
 </SECTION>
 

gst/gst.c

@@ -131,7 +131,6 @@ extern gint _gst_trace_on;
 /* set to TRUE when segfaults need to be left as is */
 gboolean _gst_disable_segtrap = FALSE;
 
-
 static void load_plugin_func (gpointer data, gpointer user_data);
 static gboolean init_pre (void);
 static gboolean init_post (void);
@@ -1055,3 +1054,40 @@ gst_version_string ()
     return g_strdup_printf ("GStreamer %d.%d.%d (prerelease)", major, minor,
         micro);
 }
+
+/**
+ * gst_segtrap_is_enabled:
+ *
+ * Some functions in the GStreamer core might install a custom SIGSEGV handler to
+ * better catch and report errors to the application. Currently this feature is 
+ * enabled by default when loading plugins.
+ *
+ * Applications might want to disable this behaviour with the
+ * gst_segtrap_set_enabled() function. This is typically done if the application
+ * wants to install its own handler without GStreamer interfering.
+ *
+ * Returns: %TRUE if GStreamer is allowed to install a custom SIGSEGV handler.
+ *
+ * Since: 0.10.10
+ */
+gboolean
+gst_segtrap_is_enabled (void)
+{
+  /* yeps, it's enabled when it's not disabled */
+  return !_gst_disable_segtrap;
+}
+
+/**
+ * gst_segtrap_set_enabled:
+ * @enabled: whether a custom SIGSEGV handler should be installed.
+ *
+ * Applications might want to disable/enable the SIGSEGV handling of
+ * the GStreamer core. See gst_segtrap_is_enabled() for more information.
+ *
+ * Since: 0.10.10
+ */
+void
+gst_segtrap_set_enabled (gboolean enabled)
+{
+  _gst_disable_segtrap = !enabled;
+}

gst/gst.h

@@ -85,6 +85,9 @@ void		gst_version			(guint *major, guint *minor,
 						 guint *micro, guint *nano);
 gchar *		gst_version_string		(void);
 
+gboolean        gst_segtrap_is_enabled          (void);
+void            gst_segtrap_set_enabled         (gboolean enabled);
+
 G_END_DECLS
 
 #endif /* __GST_H__ */

gst/gstplugin.c

@@ -279,6 +279,10 @@ _gst_plugin_fault_handler_restore (void)
 {
   struct sigaction action;
 
+  /* if asked to leave segfaults alone, just return */
+  if (_gst_disable_segtrap)
+    return;
+
   memset (&action, 0, sizeof (action));
   action.sa_handler = SIG_DFL;