Move pending seek operations from ChunkDemuxer to Demuxer.
This moves StartWaitingForSeek() and CancelPendingSeek() to the Demuxer
base class. The main advantage is that this removes the need to
specialize for ChunkDemuxer; instead PipelineController can just issue
these operations for every demuxer. In the future, this may provide an
API for aborting seeks in FFmpegDemuxer.
PipelineController is changed to accept a flag that indicates whether
the data source is 'static' (meaining that the data doesn't change); for
now all data sources are static except for MSE which is never static.
Review URL: https://codereview.chromium.org/1774043002
Cr-Commit-Position: refs/heads/master@{#380026}
diff --git a/media/base/demuxer.h b/media/base/demuxer.h
index 7e1dbc8..6e1344b 100644
--- a/media/base/demuxer.h
+++ b/media/base/demuxer.h
@@ -85,6 +85,32 @@
const PipelineStatusCB& status_cb,
bool enable_text_tracks) = 0;
+ // Indicates that a new Seek() call is on its way. Implementations may abort
+ // pending reads and future Read() calls may return kAborted until Seek() is
+ // executed. |seek_time| is the presentation timestamp of the new Seek() call.
+ //
+ // In actual use, this call occurs on the main thread while Seek() is called
+ // on the media thread. StartWaitingForSeek() can be used to synchronize the
+ // two.
+ //
+ // StartWaitingForSeek() MUST be called before Seek().
+ virtual void StartWaitingForSeek(base::TimeDelta seek_time) = 0;
+
+ // Indicates that the current Seek() operation is obsoleted by a new one.
+ // Implementations can expect that StartWaitingForSeek() will be called
+ // when the current seek operation completes.
+ //
+ // Like StartWaitingForSeek(), CancelPendingSeek() is called on the main
+ // thread. Ordering with respect to the to-be-canceled Seek() is not
+ // guaranteed. Regardless of ordering, implementations may abort pending reads
+ // and may return kAborted from future Read() calls, until after
+ // StartWaitingForSeek() and the following Seek() call occurs.
+ //
+ // |seek_time| should match that passed to the next StartWaitingForSeek(), but
+ // may not if the seek target changes again before the current seek operation
+ // completes or is aborted.
+ virtual void CancelPendingSeek(base::TimeDelta seek_time) = 0;
+
// Carry out any actions required to seek to the given time, executing the
// callback upon completion.
virtual void Seek(base::TimeDelta time,
