ffmpeg: restructure sending EOF to filters

Be more careful when an input stream encounters EOF when its filtergraph
has not been configured yet. The current code would immediately mark the
corresponding output streams as finished, while there may still be
buffered frames waiting for frames to appear on other filtergraph
inputs.

This should fix the random FATE failures for complex filtergraph tests
after a3a0230a9870b9018dc7415ae5872784d524cfe5

This merges Libav commit 94ebf55. It was previously skipped.

This is the last filter init related Libav commit that was skipped, so
this also removes the commits from doc/libav-merge.txt.

Signed-off-by: wm4 <nfxjfg@googlemail.com>

4 files changed, 43 insertions, 12 deletions

diff --git a/doc/libav-merge.txt b/doc/libav-merge.txt
index 23b48d1e2b..39d846f8fc 100644
--- a/doc/libav-merge.txt
+++ b/doc/libav-merge.txt
@@ -95,7 +95,6 @@ Stuff that didn't reach the codebase:
   - 0cef06df0 checkasm: add HEVC MC tests
   - e7078e842 hevcdsp: add x86 SIMD for MC
 - QSV scaling filter (62c58c5)
-- ffmpeg.c filter init decoupling (3e265ca,a3a0230,d2e56cf,94ebf55)
 
 Collateral damage that needs work locally:
 ------------------------------------------
diff --git a/ffmpeg.c b/ffmpeg.c
index f52d3e2f0f..275894dbf5 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -2197,6 +2197,34 @@ static int ifilter_send_frame(InputFilter *ifilter, AVFrame *frame)
     return 0;
 }
 
+static int ifilter_send_eof(InputFilter *ifilter)
+{
+    int i, j, ret;
+
+    ifilter->eof = 1;
+
+    if (ifilter->filter) {
+        ret = av_buffersrc_add_frame_flags(ifilter->filter, NULL, AV_BUFFERSRC_FLAG_PUSH);
+        if (ret < 0)
+            return ret;
+    } else {
+        // the filtergraph was never configured
+        FilterGraph *fg = ifilter->graph;
+        for (i = 0; i < fg->nb_inputs; i++)
+            if (!fg->inputs[i]->eof)
+                break;
+        if (i == fg->nb_inputs) {
+            // All the input streams have finished without the filtergraph
+            // ever being configured.
+            // Mark the output streams as finished.
+            for (j = 0; j < fg->nb_outputs; j++)
+                finish_output_stream(fg->outputs[j]->ost);
+        }
+    }
+
+    return 0;
+}
+
 // This does not quite work like avcodec_decode_audio4/avcodec_decode_video2.
 // There is the following difference: if you got a frame, you must call
 // it again with pkt=NULL. pkt==NULL is treated differently from pkt.size==0
@@ -2498,18 +2526,11 @@ out:
 
 static int send_filter_eof(InputStream *ist)
 {
-    int i, j, ret;
+    int i, ret;
     for (i = 0; i < ist->nb_filters; i++) {
-        if (ist->filters[i]->filter) {
-            ret = av_buffersrc_add_frame(ist->filters[i]->filter, NULL);
-            if (ret < 0)
-                return ret;
-        } else {
-            // the filtergraph was never configured
-            FilterGraph *fg = ist->filters[i]->graph;
-            for (j = 0; j < fg->nb_outputs; j++)
-                finish_output_stream(fg->outputs[j]->ost);
-        }
+        ret = ifilter_send_eof(ist->filters[i]);
+        if (ret < 0)
+            return ret;
     }
     return 0;
 }
diff --git a/ffmpeg.h b/ffmpeg.h
index 56e35ebb9c..5d20d453eb 100644
--- a/ffmpeg.h
+++ b/ffmpeg.h
@@ -248,6 +248,8 @@ typedef struct InputFilter {
     uint64_t channel_layout;
 
     AVBufferRef *hw_frames_ctx;
+
+    int eof;
 } InputFilter;
 
 typedef struct OutputFilter {
diff --git a/ffmpeg_filter.c b/ffmpeg_filter.c
index 4d9a4e2eb8..816c906c7e 100644
--- a/ffmpeg_filter.c
+++ b/ffmpeg_filter.c
@@ -1128,6 +1128,15 @@ int configure_filtergraph(FilterGraph *fg)
         }
     }
 
+    /* send the EOFs for the finished inputs */
+    for (i = 0; i < fg->nb_inputs; i++) {
+        if (fg->inputs[i]->eof) {
+            ret = av_buffersrc_add_frame(fg->inputs[i]->filter, NULL);
+            if (ret < 0)
+                return ret;
+        }
+    }
+
     return 0;
 }