docs/design/part-qos.txt: Fix typo.

Original commit message from CVS:
* docs/design/part-qos.txt:
Fix typo.
* gst/gstevent.c:
* gst/gstevent.h:
Update seek event docs regarding negative rates.
Rename @cur to @start.
* gst/gstsegment.c: (gst_segment_set_seek):
* gst/gstsegment.h:
Update set_seek docs regarding negative rates.
Correctly update last_stop to @stop when dealing with negative
rates.
Rename @cur to @start.
* tests/check/gst/gstpad.c: (GST_START_TEST):
Activate pads before trying to use them.
* tests/check/gst/gstsegment.c: (GST_START_TEST),
(gst_segment_suite):
Add simple check for segments and negative rates.

ChangeLog

@@ -1,3 +1,27 @@
+2006-10-09  Wim Taymans  <wim@fluendo.com>
+
+	* docs/design/part-qos.txt:
+	Fix typo.
+
+	* gst/gstevent.c:
+	* gst/gstevent.h:
+	Update seek event docs regarding negative rates.
+	Rename @cur to @start. 
+
+	* gst/gstsegment.c: (gst_segment_set_seek):
+	* gst/gstsegment.h:
+	Update set_seek docs regarding negative rates.
+	Correctly update last_stop to @stop when dealing with negative
+	rates.
+	Rename @cur to @start. 
+
+	* tests/check/gst/gstpad.c: (GST_START_TEST):
+	Activate pads before trying to use them.
+
+	* tests/check/gst/gstsegment.c: (GST_START_TEST),
+	(gst_segment_suite):
+	Add simple check for segments and negative rates.
+
 2006-10-09  Tim-Philipp Müller  <tim at centricular dot net>
 
 	* gst/gsttaglist.c: (gst_tag_list_is_empty):

docs/design/part-qos.txt

@@ -32,9 +32,9 @@ The QoS event travels upstream and contains the following fields:
 
  - timestamp:  The timestamp on the buffer that generated the QoS
                event. These timestamps are expressed in total running time in
-	       the sink so that the value is every increasing.
+	       the sink so that the value is ever increasing.
 
- - jitter:     The difference of that timestamp against the currentl clock time.
+ - jitter:     The difference of that timestamp against the current clock time.
                Negative values mean the timestamp was on time. Positive values
 	       indicate the timestamp was late by that amount.
 

gst/gstevent.c

@@ -785,33 +785,34 @@ gst_event_parse_qos (GstEvent * event, gdouble * proportion,
  * @rate: The new playback rate
  * @format: The format of the seek values
  * @flags: The optional seek flags
- * @cur_type: The type and flags for the new current position
+ * @start_type: The type and flags for the new start position
- * @cur: The value of the new current position
+ * @start: The value of the new start position
  * @stop_type: The type and flags for the new stop position
  * @stop: The value of the new stop position
  *
  * Allocate a new seek event with the given parameters.
  *
- * The seek event configures playback of the pipeline from
+ * The seek event configures playback of the pipeline between @start to @stop
- * @cur to @stop at the speed given in @rate, also called a playback segment.
+ * at the speed given in @rate, also called a playback segment.
- * The @cur and @stop values are expressed in format @format.
+ * The @start and @stop values are expressed in @format.
  *
  * A @rate of 1.0 means normal playback rate, 2.0 means double speed.
  * Negatives values means backwards playback. A value of 0.0 for the
  * rate is not allowed and should be accomplished instead by PAUSING the
  * pipeline.
  *
- * A pipeline has a default playback segment configured with a current
+ * A pipeline has a default playback segment configured with a start
- * position of 0, a stop position of the total duration of the stream(s) and
+ * position of 0, a stop position of -1 and a rate of 1.0. The currently
- * a rate of 1.0. The currently configured playback segment can be queried
+ * configured playback segment can be queried with #GST_QUERY_SEGMENT. 
- * with #GST_QUERY_SEGMENT. 
  *
- * @cur_type and @stop_type specify how to adjust the current and stop
+ * @start_type and @stop_type specify how to adjust the currently configured 
- * time, relative or absolute to the last configured playback segment. A type
+ * start and stop fields in @segment. Adjustments can be made relative or
- * of #GST_SEEK_TYPE_NONE means that the position should not be updated.
+ * absolute to the last configured values. A type of #GST_SEEK_TYPE_NONE means
+ * that the position should not be updated.
  *
- * Updating the @cur position will actually move the current playback position
+ * When the rate is positive and @start has been updated, playback will start
- * to that new position. 
+ * from the newly configured start position. For negative rates, playback will
+ * start from the newly configured stop position.
  *
  * It is not possible to seek relative to the current playback position, to do
  * this, PAUSE the pipeline, query the current playback position with

gst/gstevent.h

@@ -411,11 +411,11 @@ void		gst_event_parse_qos		(GstEvent *event, gdouble *proportion, GstClockTimeDi
 						 GstClockTime *timestamp);
 /* seek event */
 GstEvent*	gst_event_new_seek		(gdouble rate, GstFormat format, GstSeekFlags flags,
-						 GstSeekType cur_type, gint64 cur,
+						 GstSeekType start_type, gint64 start,
 						 GstSeekType stop_type, gint64 stop);
 void		gst_event_parse_seek		(GstEvent *event, gdouble *rate, GstFormat *format,
 		                                 GstSeekFlags *flags,
-						 GstSeekType *cur_type, gint64 *cur,
+						 GstSeekType *start_type, gint64 *start,
 						 GstSeekType *stop_type, gint64 *stop);
 /* navigation event */
 GstEvent*	gst_event_new_navigation	(GstStructure *structure);

gst/gstsegment.c

@@ -172,7 +172,7 @@ gst_segment_init (GstSegment * segment, GstFormat format)
  * gst_segment_set_duration:
  * @segment: a #GstSegment structure.
  * @format: the format of the segment.
- * @duration: the duration of the segment info.
+ * @duration: the duration of the segment info or -1 if unknown.
  *
  * Set the duration of the segment to @duration. This function is mainly
  * used by elements that perform seeking and know the total duration of the
@@ -226,19 +226,31 @@ gst_segment_set_last_stop (GstSegment * segment, GstFormat format,
  * @rate: the rate of the segment.
  * @format: the format of the segment.
  * @flags: the seek flags for the segment
- * @cur_type: the seek method
+ * @start_type: the seek method
- * @cur: the seek start value
+ * @start: the seek start value
  * @stop_type: the seek method
  * @stop: the seek stop value
  * @update: boolean holding whether start or stop were updated.
  *
- * Update the segment structure with the field values of a seek event.
+ * Update the segment structure with the field values of a seek event (see
+ * gst_event_new_seek()).
  *
- * After calling this method, the segment field last_stop will contain
+ * After calling this method, the segment field last_stop and time will
- * the requested new position in the segment. If the cur_type is different
+ * contain the requested new position in the segment. The new requested
- * from GST_SEEK_TYPE_NONE, the current position is not updated and 
+ * position in the segment depends on @rate and @start_type and @stop_type. 
- * streaming should continue from the last position, possibly with
+ *
- * updated rate, flags or stop position.
+ * For positive @rate, the new position in the segment is the new @segment
+ * start field when it was updated with a @start_type different from
+ * #GST_SEEK_TYPE_NONE. If no update was performed on @segment start position
+ * (#GST_SEEK_TYPE_NONE), @start is ignored and @segment last_stop is
+ * unmodified.
+ *
+ * For negative @rate, the new position in the segment is the new @segment
+ * stop field when it was updated with a @stop_type different from
+ * #GST_SEEK_TYPE_NONE. If no stop was previously configured in the segment, the
+ * duration of the segment will be used to update the stop position.
+ * If no update was performed on @segment stop position (#GST_SEEK_TYPE_NONE),
+ * @stop is ignored and @segment last_stop is unmodified.
  *
  * The applied rate of the segment will be set to 1.0 by default.
  * If the caller can apply a rate change, it should update @segment
@@ -247,7 +259,7 @@ gst_segment_set_last_stop (GstSegment * segment, GstFormat format,
 void
 gst_segment_set_seek (GstSegment * segment, gdouble rate,
     GstFormat format, GstSeekFlags flags,
-    GstSeekType cur_type, gint64 cur,
+    GstSeekType start_type, gint64 start,
     GstSeekType stop_type, gint64 stop, gboolean * update)
 {
   gboolean update_stop, update_start;
@@ -263,35 +275,35 @@ gst_segment_set_seek (GstSegment * segment, gdouble rate,
   update_stop = update_start = TRUE;
 
   /* start is never invalid */
-  switch (cur_type) {
+  switch (start_type) {
     case GST_SEEK_TYPE_NONE:
       /* no update to segment */
-      cur = segment->start;
+      start = segment->start;
       update_start = FALSE;
       break;
     case GST_SEEK_TYPE_SET:
-      /* cur holds desired position */
+      /* start holds desired position */
       break;
     case GST_SEEK_TYPE_CUR:
-      /* add cur to currently configure segment */
+      /* add start to currently configure segment */
-      cur = segment->start + cur;
+      start = segment->start + start;
       break;
     case GST_SEEK_TYPE_END:
       if (segment->duration != -1) {
-        /* add cur to total length */
+        /* add start to total length */
-        cur = segment->duration + cur;
+        start = segment->duration + start;
       } else {
         /* no update if duration unknown */
-        cur = segment->start;
+        start = segment->start;
         update_start = FALSE;
       }
       break;
   }
   /* bring in sane range */
   if (segment->duration != -1)
-    cur = CLAMP (cur, 0, segment->duration);
+    start = CLAMP (start, 0, segment->duration);
   else
-    cur = MAX (cur, 0);
+    start = MAX (start, 0);
 
   /* stop can be -1 if we have not configured a stop. */
   switch (stop_type) {
@@ -328,15 +340,18 @@ gst_segment_set_seek (GstSegment * segment, gdouble rate,
 
   /* we can't have stop before start */
   if (stop != -1)
-    g_return_if_fail (cur <= stop);
+    g_return_if_fail (start <= stop);
 
   segment->rate = rate;
   segment->abs_rate = ABS (rate);
   segment->applied_rate = 1.0;
   segment->flags = flags;
-  segment->start = cur;
+  segment->start = start;
-  if (update_start) {
+  if (update_start && rate > 0.0) {
-    segment->last_stop = cur;
+    segment->last_stop = start;
+  }
+  if (update_stop && rate < 0.0) {
+    segment->last_stop = stop;
   }
   segment->time = segment->last_stop;
   segment->stop = stop;

gst/gstsegment.h

@@ -83,7 +83,7 @@ void         gst_segment_set_last_stop       (GstSegment *segment, GstFormat for
 
 void         gst_segment_set_seek            (GstSegment *segment, gdouble rate,
                                               GstFormat format, GstSeekFlags flags,
-                                              GstSeekType cur_type, gint64 cur,
+                                              GstSeekType start_type, gint64 start,
                                               GstSeekType stop_type, gint64 stop,
                                               gboolean *update);
 

tests/check/gst/gstpad.c

@@ -333,9 +333,21 @@ GST_START_TEST (test_push_linked)
   fail_unless (GST_PAD_LINK_SUCCESSFUL (plr));
   ASSERT_CAPS_REFCOUNT (caps, "caps", 3);
 
+  buffer = gst_buffer_new ();
+#if 0
+  /* FIXME, new pad should be flushing */
+  gst_buffer_ref (buffer);
+  fail_unless (gst_pad_push (src, buffer) == GST_FLOW_WRONG_STATE);
+  gst_buffer_ref (buffer);
+  fail_unless (gst_pad_chain (sink, buffer) == GST_FLOW_WRONG_STATE);
+#endif
+
+  /* activate pads */
+  gst_pad_set_active (src, TRUE);
+  gst_pad_set_active (sink, TRUE);
+
   /* test */
   /* pushing on a linked pad will drop the ref to the buffer */
-  buffer = gst_buffer_new ();
   gst_buffer_ref (buffer);
   fail_unless (gst_pad_push (src, buffer) == GST_FLOW_OK);
   ASSERT_MINI_OBJECT_REFCOUNT (buffer, "buffer", 2);

tests/check/gst/gstsegment.c

@@ -380,6 +380,43 @@ GST_START_TEST (segment_seek_size)
 
 GST_END_TEST;
 
+GST_START_TEST (segment_seek_reverse)
+{
+  GstSegment segment;
+  gboolean update;
+
+  gst_segment_init (&segment, GST_FORMAT_BYTES);
+  gst_segment_set_duration (&segment, GST_FORMAT_BYTES, 200);
+
+  /* configure segment to stop 100 */
+  gst_segment_set_seek (&segment, -1.0,
+      GST_FORMAT_BYTES,
+      GST_SEEK_FLAG_NONE,
+      GST_SEEK_TYPE_SET, 0, GST_SEEK_TYPE_SET, 100, &update);
+  fail_unless (segment.start == 0);
+  fail_unless (segment.stop == 100);
+  fail_unless (segment.last_stop == 100);
+
+  /* update */
+  gst_segment_set_seek (&segment, -1.0,
+      GST_FORMAT_BYTES,
+      GST_SEEK_FLAG_NONE,
+      GST_SEEK_TYPE_SET, 10, GST_SEEK_TYPE_CUR, -20, &update);
+  fail_unless (segment.start == 10);
+  fail_unless (segment.stop == 80);
+  fail_unless (segment.last_stop == 80);
+
+  gst_segment_set_seek (&segment, -1.0,
+      GST_FORMAT_BYTES,
+      GST_SEEK_FLAG_NONE,
+      GST_SEEK_TYPE_SET, 20, GST_SEEK_TYPE_NONE, 0, &update);
+  fail_unless (segment.start == 20);
+  fail_unless (segment.stop == 80);
+  fail_unless (segment.last_stop == 80);
+}
+
+GST_END_TEST;
+
 /* mess with the segment structure in the bytes format */
 GST_START_TEST (segment_newsegment_open)
 {
@@ -1289,6 +1326,7 @@ gst_segment_suite (void)
   suite_add_tcase (s, tc_chain);
   tcase_add_test (tc_chain, segment_seek_nosize);
   tcase_add_test (tc_chain, segment_seek_size);
+  tcase_add_test (tc_chain, segment_seek_reverse);
   tcase_add_test (tc_chain, segment_newsegment_open);
   tcase_add_test (tc_chain, segment_newsegment_closed);
   tcase_add_test (tc_chain, segment_newsegment_streamtime);