avfilter/asubprocess: improve eof handling

Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

libavfilter/af_asubprocess.c

 #include "libavutil/opt.h"
 #include "libavutil/mem.h"
 #include "libavutil/intreadwrite.h"
+#include "libavutil/avassert.h"
 #include "libavformat/avio.h"
 #include "libavformat/avio_internal.h"
 
@@ -21,7 +22,6 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <fcntl.h>
-#include <assert.h>
 #include <poll.h>
 #include <stdlib.h>
 #include <stdbool.h>
@@ -31,18 +31,19 @@
 
 typedef struct SPB
 {
-  struct SPB *next;
-  int offset;
-  int count;
-  char data[BUFFER_SIZE];
+    struct SPB *next;
+    int offset;
+    int count;
+    char data[BUFFER_SIZE];
 } SPB;
 
 typedef struct SP
 {
-  int input_pipe;
-  int output_pipe;
-  SPB *out_buffers;
-  int pid;
+    int input_pipe;
+    int output_pipe;
+    SPB *out_buffers;
+    int pid;
+    bool done;
 } SP;
 
 static SPB *spb_new(void)
@@ -90,11 +91,11 @@ sp_new (const char *command)
   close (input_pipe[0]);
   close (output_pipe[1]);
   i = fcntl(output_pipe[0], F_GETFL);
-  assert(i != -1);
+  av_assert0(i != -1);
   i |= O_NONBLOCK;
   fcntl(output_pipe[0], F_SETFL, i);
   i = fcntl(input_pipe[1], F_GETFL);
-  assert(i != -1);
+  av_assert0(i != -1);
   i |= O_NONBLOCK;
   fcntl(input_pipe[1], F_SETFL, i);
   sp->input_pipe = input_pipe[1];
@@ -136,7 +137,7 @@ sp_read (SP *sp, char *buffer, int count)
     }
 }
 
-static bool
+static void
 sp_write (SP *sp, char *buffer, int count)
 {
   int offset = 0;
@@ -183,11 +184,17 @@ sp_write (SP *sp, char *buffer, int count)
               int status;
               waitpid (sp->pid, &status, 0);
               printf ("wstatus=%d\n", WEXITSTATUS (status));
-              return true;
+              sp->done = true;
+              return;
             }
         }
     } while (count);
-  return false;
+}
+
+static bool
+sp_done (SP *sp)
+{
+    return sp->done;
 }
 // =============================================
 
@@ -311,7 +318,6 @@ static int config_input(AVFilterLink *inlink)
 static void read_samples(ASubProcessContext *s, int32_t *data, int count)
 {
     int sample_size = s->in_bit_depth / 8;
-    assert(in->nb_samples <= NB_BUFFER_SAMPLES);
 #if !HAVE_BIGENDIAN
     if (s->out_bit_depth == 32)
     {
@@ -353,10 +359,9 @@ static void read_samples(ASubProcessContext *s, int32_t *data, int count)
 static void write_samples(ASubProcessContext *s, int32_t *data, int count)
 {
     int sample_size = s->in_bit_depth / 8;
-    assert(in->nb_samples <= NB_BUFFER_SAMPLES);
 
 #if !HAVE_BIGENDIAN
-    if (s->out_bit_depth == 32)
+    if (s->in_bit_depth == 32)
     {
         /* optimized case: on little endian systems we don't need any conversion */
         sp_write(s->sp, (char *)data, sample_size * count);
@@ -391,13 +396,8 @@ static int write_frame(ASubProcessContext *s, AVFilterLink *inlink, AVFrame *in)
 {
     int ret = 0;
 
+    av_assert0(in->nb_samples <= NB_BUFFER_SAMPLES);
     write_samples(s, (int32_t *)in->data[0], in->nb_samples * inlink->ch_layout.nb_channels);
-    if (s->eof)
-    {
-        while (!sp_write (s->sp, 0, 0))
-            ;
-        printf ("eof\n");
-    }
     av_frame_free(&in);
     return ret;
 }
@@ -456,6 +456,7 @@ static int try_read_frame(ASubProcessContext *s, AVFilterLink *outlink)
             if (!out) {
                 return AVERROR(ENOMEM);
             }
+            av_assert0(avail <= NB_BUFFER_SAMPLES);
             read_samples(s, (int32_t *)out->data[0], avail * outlink->ch_layout.nb_channels);
             ret = ff_filter_frame(outlink, out);
             if (ret < 0)
@@ -498,6 +499,12 @@ static int activate(AVFilterContext *ctx)
         if (ret != 0)
             return ret;
     }
+    if (s->eof && !sp_done (s->sp))
+    {
+        while (!sp_done (s->sp))
+            sp_write (s->sp, 0, 0);
+        printf ("eof\n");
+    }
     ret = try_read_frame(s, outlink);
     if (ret != 0)
         return ret;