adaptivedemux: handle snap seeking without setting any position

When the start_type is GST_SEEK_TYPE_NONE for a forward seek
(or stop_type for a reverse) is not set on a snap seeking operation,
the element should use the current position and then snap as requested.

Also fixes uninitialized variable complaint by clang about
'ts' variable.

2 files changed, 69 insertions, 30 deletions

diff --git a/gst-libs/gst/adaptivedemux/gstadaptivedemux.c b/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
index ae6ce2cb5..a83b9d194 100644
--- a/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
+++ b/gst-libs/gst/adaptivedemux/gstadaptivedemux.c
@@ -1305,20 +1305,6 @@ gst_adaptive_demux_src_event (GstPad * pad, GstObject * parent,
       }
 
       GST_ADAPTIVE_DEMUX_SEGMENT_LOCK (demux);
-      gst_segment_do_seek (&demux->segment, rate, format, flags, start_type,
-          start, stop_type, stop, &update);
-
-      /* FIXME - this seems unatural, do_seek() is updating base when we
-       * only want the start/stop position to change, maybe do_seek() needs
-       * some fixing? */
-      if (!(flags & GST_SEEK_FLAG_FLUSH) && ((rate > 0
-                  && start_type == GST_SEEK_TYPE_NONE) || (rate < 0
-                  && stop_type == GST_SEEK_TYPE_NONE))) {
-        demux->segment.base = oldsegment.base;
-      }
-
-      GST_DEBUG_OBJECT (demux, "Seeking to segment %" GST_SEGMENT_FORMAT,
-          &demux->segment);
 
       /*
        * Handle snap seeks as follows:
@@ -1341,10 +1327,20 @@ gst_adaptive_demux_src_event (GstPad * pad, GstObject * parent,
         /* snap-seek on the stream that received the event and then
          * use the resulting position to seek on all streams */
 
-        if (rate >= 0 && start_type != GST_SEEK_TYPE_NONE) {
-          ts = start;
-        } else if (rate < 0 && stop_type != GST_SEEK_TYPE_NONE) {
-          ts = stop;
+        if (rate >= 0) {
+          if (start_type != GST_SEEK_TYPE_NONE)
+            ts = start;
+          else {
+            ts = stream->segment.position;
+            start_type = GST_SEEK_TYPE_SET;
+          }
+        } else {
+          if (stop_type != GST_SEEK_TYPE_NONE)
+            ts = stop;
+          else {
+            stop_type = GST_SEEK_TYPE_SET;
+            ts = stream->segment.position;
+          }
         }
 
         demux_class->stream_seek (stream, rate >= 0, stream_seek_flags, ts,
@@ -1352,9 +1348,9 @@ gst_adaptive_demux_src_event (GstPad * pad, GstObject * parent,
 
         /* replace event with a new one without snaping to seek on all streams */
         gst_event_unref (event);
-        if (rate >= 0 && start_type != GST_SEEK_TYPE_NONE) {
+        if (rate >= 0) {
           start = ts;
-        } else if (rate < 0 && stop_type != GST_SEEK_TYPE_NONE) {
+        } else {
           stop = ts;
         }
         event =
@@ -1363,8 +1359,22 @@ gst_adaptive_demux_src_event (GstPad * pad, GstObject * parent,
         GST_DEBUG_OBJECT (demux, "Adapted snap seek to %" GST_PTR_FORMAT,
             event);
       }
+
+      gst_segment_do_seek (&demux->segment, rate, format, flags, start_type,
+          start, stop_type, stop, &update);
+
+      /* FIXME - this seems unatural, do_seek() is updating base when we
+       * only want the start/stop position to change, maybe do_seek() needs
+       * some fixing? */
+      if (!(flags & GST_SEEK_FLAG_FLUSH) && ((rate > 0
+                  && start_type == GST_SEEK_TYPE_NONE) || (rate < 0
+                  && stop_type == GST_SEEK_TYPE_NONE))) {
+        demux->segment.base = oldsegment.base;
+      }
+
       GST_DEBUG_OBJECT (demux, "Calling subclass seek: %" GST_PTR_FORMAT,
           event);
+
       ret = demux_class->seek (demux, event);
 
       if (!ret) {
diff --git a/tests/check/elements/dash_demux.c b/tests/check/elements/dash_demux.c
index de240a571..961e12e1b 100644
--- a/tests/check/elements/dash_demux.c
+++ b/tests/check/elements/dash_demux.c
@@ -500,11 +500,12 @@ GST_START_TEST (testSeek)
 GST_END_TEST;
 
 
+#define SEGMENT_SIZE 10000
 static void
 run_seek_position_test (gdouble rate, GstSeekType start_type,
     guint64 seek_start, GstSeekType stop_type, guint64 seek_stop,
     GstSeekFlags flags, guint64 segment_start, guint64 segment_stop,
-    gint segments)
+    gint segments, gint seek_threshold_bytes)
 {
   const gchar *mpd =
       "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
@@ -549,7 +550,7 @@ run_seek_position_test (gdouble rate, GstSeekType start_type,
   GstTestHTTPSrcCallbacks http_src_callbacks = { 0 };
   GstAdaptiveDemuxTestExpectedOutput outputTestData[] = {
     /* 1 from the init segment */
-    {"audio_00", (1 + segments) * 10000, NULL},
+    {"audio_00", (segments ? 1 + segments : 0) * 10000, NULL},
   };
   GstAdaptiveDemuxTestCase *testData;
 
@@ -564,7 +565,10 @@ run_seek_position_test (gdouble rate, GstSeekType start_type,
    * on the first pad listed in GstAdaptiveDemuxTestOutputStreamData and the
    * first chunk of at least one byte has already arrived in AppSink
    */
-  testData->threshold_for_seek = 4687 + 1;
+  if (seek_threshold_bytes)
+    testData->threshold_for_seek = seek_threshold_bytes;
+  else
+    testData->threshold_for_seek = 4687 + 1;
 
   /* FIXME hack to avoid having a 0 seqnum */
   gst_util_seqnum_next ();
@@ -589,7 +593,7 @@ GST_START_TEST (testSeekKeyUnitPosition)
    * pushed */
   run_seek_position_test (1.0, GST_SEEK_TYPE_SET, 1500 * GST_MSECOND,
       GST_SEEK_TYPE_NONE, 0, GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_KEY_UNIT,
-      1000 * GST_MSECOND, -1, 3);
+      1000 * GST_MSECOND, -1, 3, 0);
 }
 
 GST_END_TEST;
@@ -598,7 +602,7 @@ GST_END_TEST;
 GST_START_TEST (testSeekUpdateStopPosition)
 {
   run_seek_position_test (1.0, GST_SEEK_TYPE_NONE, 1500 * GST_MSECOND,
-      GST_SEEK_TYPE_SET, 3000 * GST_MSECOND, 0, 0, 3000 * GST_MSECOND, 3);
+      GST_SEEK_TYPE_SET, 3000 * GST_MSECOND, 0, 0, 3000 * GST_MSECOND, 3, 0);
 }
 
 GST_END_TEST;
@@ -609,7 +613,7 @@ GST_START_TEST (testSeekPosition)
    * from the 1st segment, so 3 segments will be
    * pushed */
   run_seek_position_test (1.0, GST_SEEK_TYPE_SET, 1500 * GST_MSECOND,
-      GST_SEEK_TYPE_NONE, 0, GST_SEEK_FLAG_FLUSH, 1500 * GST_MSECOND, -1, 3);
+      GST_SEEK_TYPE_NONE, 0, GST_SEEK_FLAG_FLUSH, 1500 * GST_MSECOND, -1, 3, 0);
 }
 
 GST_END_TEST;
@@ -619,7 +623,7 @@ GST_START_TEST (testSeekSnapBeforePosition)
   /* Seek to 1.5s, snap before, it go to 1s */
   run_seek_position_test (1.0, GST_SEEK_TYPE_SET, 1500 * GST_MSECOND,
       GST_SEEK_TYPE_NONE, 0, GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_SNAP_BEFORE,
-      1000 * GST_MSECOND, -1, 3);
+      1000 * GST_MSECOND, -1, 3, 0);
 }
 
 GST_END_TEST;
@@ -630,18 +634,41 @@ GST_START_TEST (testSeekSnapAfterPosition)
   /* Seek to 1.5s with snap after, it should move to 2s */
   run_seek_position_test (1.0, GST_SEEK_TYPE_SET, 1500 * GST_MSECOND,
       GST_SEEK_TYPE_NONE, 0, GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_SNAP_AFTER,
-      2000 * GST_MSECOND, -1, 2);
+      2000 * GST_MSECOND, -1, 2, 0);
+}
+
+GST_END_TEST;
+
+
+GST_START_TEST (testSeekSnapBeforeSamePosition)
+{
+  /* Snap seek without position */
+  run_seek_position_test (1.0, GST_SEEK_TYPE_NONE, GST_CLOCK_TIME_NONE,
+      GST_SEEK_TYPE_NONE, 0, GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_SNAP_BEFORE,
+      2 * GST_MSECOND, -1, 2, SEGMENT_SIZE * 3 + 1);
+}
+
+GST_END_TEST;
+
+
+GST_START_TEST (testSeekSnapAfterSamePosition)
+{
+  /* Snap seek without position */
+  run_seek_position_test (1.0, GST_SEEK_TYPE_NONE, GST_CLOCK_TIME_NONE,
+      GST_SEEK_TYPE_NONE, 0, GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_SNAP_AFTER,
+      3 * GST_MSECOND, -1, 1, SEGMENT_SIZE * 3 + 1);
 }
 
 GST_END_TEST;
 
 
+
 GST_START_TEST (testReverseSeekSnapBeforePosition)
 {
   run_seek_position_test (-1.0, GST_SEEK_TYPE_SET, 1000 * GST_MSECOND,
       GST_SEEK_TYPE_SET, 2500 * GST_MSECOND,
       GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_SNAP_BEFORE, 1000 * GST_MSECOND,
-      3000 * GST_MSECOND, 2);
+      3000 * GST_MSECOND, 2, 0);
 }
 
 GST_END_TEST;
@@ -652,7 +679,7 @@ GST_START_TEST (testReverseSeekSnapAfterPosition)
   run_seek_position_test (-1.0, GST_SEEK_TYPE_SET, 1000 * GST_MSECOND,
       GST_SEEK_TYPE_SET, 2500 * GST_MSECOND,
       GST_SEEK_FLAG_FLUSH | GST_SEEK_FLAG_SNAP_AFTER, 1000 * GST_MSECOND,
-      2000 * GST_MSECOND, 1);
+      2000 * GST_MSECOND, 1, 0);
 }
 
 GST_END_TEST;
@@ -982,6 +1009,8 @@ dash_demux_suite (void)
   tcase_add_test (tc_basicTest, testSeekUpdateStopPosition);
   tcase_add_test (tc_basicTest, testSeekSnapBeforePosition);
   tcase_add_test (tc_basicTest, testSeekSnapAfterPosition);
+  tcase_add_test (tc_basicTest, testSeekSnapBeforeSamePosition);
+  tcase_add_test (tc_basicTest, testSeekSnapAfterSamePosition);
   tcase_add_test (tc_basicTest, testReverseSeekSnapBeforePosition);
   tcase_add_test (tc_basicTest, testReverseSeekSnapAfterPosition);
   tcase_add_test (tc_basicTest, testDownloadError);