ffmpeg: factorize input thread creation and destruction

Signed-off-by: Marton Balint <cus@passwd.hu>

fftools/ffmpeg.c

@@ -4053,16 +4053,13 @@ static void *input_thread(void *arg)
     return NULL;
 }
 
-static void free_input_threads(void)
+static void free_input_thread(int i)
 {
-    int i;
-
-    for (i = 0; i < nb_input_files; i++) {
     InputFile *f = input_files[i];
     AVPacket pkt;
 
     if (!f || !f->in_thread_queue)
-            continue;
+        return;
     av_thread_message_queue_set_err_send(f->in_thread_queue, AVERROR_EOF);
     while (av_thread_message_queue_recv(f->in_thread_queue, &pkt, 0) >= 0)
         av_packet_unref(&pkt);
@@ -4070,19 +4067,24 @@ static void free_input_threads(void)
     pthread_join(f->thread, NULL);
     f->joined = 1;
     av_thread_message_queue_free(&f->in_thread_queue);
-    }
 }
 
-static int init_input_threads(void)
+static void free_input_threads(void)
 {
-    int i, ret;
+    int i;
 
-    if (nb_input_files == 1)
-        return 0;
+    for (i = 0; i < nb_input_files; i++)
+        free_input_thread(i);
+}
 
-    for (i = 0; i < nb_input_files; i++) {
+static int init_input_thread(int i)
+{
+    int ret;
     InputFile *f = input_files[i];
 
+    if (nb_input_files == 1)
+        return 0;
+
     if (f->ctx->pb ? !f->ctx->pb->seekable :
         strcmp(f->ctx->iformat->name, "lavfi"))
         f->non_blocking = 1;
@@ -4096,6 +4098,18 @@ static int init_input_threads(void)
         av_thread_message_queue_free(&f->in_thread_queue);
         return AVERROR(ret);
     }
+
+    return 0;
+}
+
+static int init_input_threads(void)
+{
+    int i, ret;
+
+    for (i = 0; i < nb_input_files; i++) {
+        ret = init_input_thread(i);
+        if (ret < 0)
+            return ret;
     }
     return 0;
 }