[vlc-devel] [PATCH 2/9] RFC: audio_output: fix buffers_lost count

[Thomas Guillem]

aout_FiltersPlay can return NULL without loosing a buffer (the block can still
be in filters internals)

This is hackish and I'm not sure this will work in all cases .

Should we change pf_*_filter to differentiate an error from an absence of block
?
---
 src/audio_output/aout_internal.h |  2 ++
 src/audio_output/dec.c           | 20 ++++++++++++++++----
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/src/audio_output/aout_internal.h b/src/audio_output/aout_internal.h
index c6edf8e..5592e22 100644
--- a/src/audio_output/aout_internal.h
+++ b/src/audio_output/aout_internal.h
@@ -80,6 +80,8 @@ typedef struct
 
     aout_request_vout_t request_vout;
 
+    mtime_t last_dts;
+    unsigned buffers_filtered_count;
     atomic_uint buffers_lost;
     atomic_uint buffers_played;
     atomic_uchar restart;
diff --git a/src/audio_output/dec.c b/src/audio_output/dec.c
index c1cc1db..ca2105f 100644
--- a/src/audio_output/dec.c
+++ b/src/audio_output/dec.c
@@ -107,6 +107,8 @@ error:
     owner->sync.discontinuity = true;
     aout_OutputUnlock (p_aout);
 
+    owner->last_dts = VLC_TS_INVALID;
+    owner->buffers_filtered_count = 0;
     atomic_init (&owner->buffers_lost, 0);
     atomic_init (&owner->buffers_played, 0);
     return 0;
@@ -374,9 +376,22 @@ int aout_DecPlay (audio_output_t *aout, block_t *block, int input_rate)
     if (block->i_flags & BLOCK_FLAG_DISCONTINUITY)
         owner->sync.discontinuity = true;
 
+    mtime_t last_dts = block->i_dts;
     block = aout_FiltersPlay (owner->filters, block, input_rate);
     if (block == NULL)
-        goto lost;
+    {
+        if (owner->last_dts != VLC_TS_INVALID)
+            owner->last_dts = last_dts;
+        owner->buffers_filtered_count++;
+        goto out;
+    }
+    else if (owner->last_dts != VLC_TS_INVALID && block->i_dts > owner->last_dts)
+    {
+        assert( owner->buffers_filtered_count > 0 );
+        atomic_fetch_add(&owner->buffers_lost, owner->buffers_filtered_count);
+    }
+    owner->last_dts = VLC_TS_INVALID;
+    owner->buffers_filtered_count = 0;
 
     /* Software volume */
     aout_volume_Amplify (owner->volume, block);
@@ -395,9 +410,6 @@ out:
 drop:
     owner->sync.discontinuity = true;
     block_Release (block);
-lost:
-    atomic_fetch_add(&owner->buffers_lost, 1);
-    goto out;
 }
 
 void aout_DecGetResetStats(audio_output_t *aout, unsigned *restrict lost,
-- 
2.9.3