gst: Add missing G_GNUC_NULL_TERMINATED markers

Functions that require NULL as their last vararg are marked so the
compiler can warn on missing NULL.

Also, document the NULL terminator for gst_make_element_message_details()
and gst_tracer_record_new().

https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/669

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/774>

8 files changed, 10 insertions, 8 deletions

diff --git a/gst/gstcapsfeatures.h b/gst/gstcapsfeatures.h
index 97babb2716..aa5e72b042 100644
--- a/gst/gstcapsfeatures.h
+++ b/gst/gstcapsfeatures.h
@@ -58,7 +58,7 @@ GST_API
 GstCapsFeatures * gst_caps_features_new_any (void);
 
 GST_API
-GstCapsFeatures * gst_caps_features_new (const gchar *feature1, ...);
+GstCapsFeatures * gst_caps_features_new (const gchar *feature1, ...) G_GNUC_NULL_TERMINATED;
 
 GST_API
 GstCapsFeatures * gst_caps_features_new_valist (const gchar *feature1, va_list varargs);
diff --git a/gst/gstelement.c b/gst/gstelement.c
index 13d586edf9..23b3f45191 100644
--- a/gst/gstelement.c
+++ b/gst/gstelement.c
@@ -3845,7 +3845,8 @@ _priv_gst_element_cleanup (void)
  * @name: Name of the first field to set
  * @...: variable arguments in the same form as #GstStructure
  *
- * Create a #GstStructure to be used with #gst_element_message_full_with_details
+ * Create a #GstStructure to be used with #gst_element_message_full_with_details.
+ * %NULL terminator required.
  *
  * Since: 1.10
  */
diff --git a/gst/gstelement.h b/gst/gstelement.h
index 6b12ad2326..6740067ffe 100644
--- a/gst/gstelement.h
+++ b/gst/gstelement.h
@@ -484,7 +484,7 @@ typedef enum
 #define GST_ELEMENT_START_TIME(elem)            (GST_ELEMENT_CAST(elem)->start_time)
 
 GST_API
-GstStructure *gst_make_element_message_details (const char *name, ...);
+GstStructure *gst_make_element_message_details (const char *name, ...) G_GNUC_NULL_TERMINATED;
 
 #define GST_ELEMENT_MESSAGE_MAKE_DETAILS(args) gst_make_element_message_details args
 
diff --git a/gst/gsttaglist.h b/gst/gsttaglist.h
index 2df43c7254..c15ea2d34f 100644
--- a/gst/gsttaglist.h
+++ b/gst/gsttaglist.h
@@ -201,7 +201,7 @@ GST_API
 GstTagList * gst_tag_list_new_empty         (void) G_GNUC_MALLOC;
 
 GST_API
-GstTagList * gst_tag_list_new               (const gchar * tag, ...) G_GNUC_MALLOC;
+GstTagList * gst_tag_list_new               (const gchar * tag, ...) G_GNUC_NULL_TERMINATED G_GNUC_MALLOC;
 
 GST_API
 GstTagList * gst_tag_list_new_valist        (va_list var_args) G_GNUC_MALLOC;
diff --git a/gst/gsttracerrecord.c b/gst/gsttracerrecord.c
index 97d4c00019..1caa687135 100644
--- a/gst/gsttracerrecord.c
+++ b/gst/gsttracerrecord.c
@@ -159,6 +159,7 @@ gst_tracer_record_init (GstTracerRecord * self)
  *
  * Create a new tracer record. The record instance can be used to efficiently
  * log entries using gst_tracer_record_log().
+ * %NULL terminator required after the last argument.
  *
  * The @name without the ".class" suffix will be used for the log records.
  * There must be fields for each value that gets logged where the field name is
diff --git a/gst/gsttracerrecord.h b/gst/gsttracerrecord.h
index a7e1bb4b61..3d8c4da9c0 100644
--- a/gst/gsttracerrecord.h
+++ b/gst/gsttracerrecord.h
@@ -92,7 +92,7 @@ typedef enum
 } GstTracerValueFlags;
 
 GST_API
-GstTracerRecord * gst_tracer_record_new (const gchar * name, const gchar * firstfield, ...);
+GstTracerRecord * gst_tracer_record_new (const gchar * name, const gchar * firstfield, ...) G_GNUC_NULL_TERMINATED;
 
 #ifndef GST_DISABLE_GST_DEBUG
 GST_API
diff --git a/gst/gsttypefind.h b/gst/gsttypefind.h
index 6a0a63069f..7844adb649 100644
--- a/gst/gsttypefind.h
+++ b/gst/gsttypefind.h
@@ -196,7 +196,7 @@ GST_API
 void            gst_type_find_suggest_simple (GstTypeFind * find,
                                               guint         probability,
                                               const char  * media_type,
-                                              const char  * fieldname, ...);
+                                              const char  * fieldname, ...) G_GNUC_NULL_TERMINATED;
 GST_API
 guint64   gst_type_find_get_length (GstTypeFind   * find);
 
diff --git a/libs/gst/check/gstharness.h b/libs/gst/check/gstharness.h
index e4290d94c4..160fdb01d8 100644
--- a/libs/gst/check/gstharness.h
+++ b/libs/gst/check/gstharness.h
@@ -337,12 +337,12 @@ GstElement *  gst_harness_find_element (GstHarness * h,
 GST_CHECK_API
 void          gst_harness_set (GstHarness  * h,
                                const gchar * element_name,
-                               const gchar * first_property_name, ...);
+                               const gchar * first_property_name, ...) G_GNUC_NULL_TERMINATED;
 
 GST_CHECK_API
 void          gst_harness_get (GstHarness  * h,
                                const gchar * element_name,
-                               const gchar * first_property_name, ...);
+                               const gchar * first_property_name, ...) G_GNUC_NULL_TERMINATED;
 
 GST_CHECK_API
 void          gst_harness_add_probe (GstHarness        * h,