workaround ffmpeg hybrid_fragmented bug when no packets have been recorded yet

1 files changed, 28 insertions, 0 deletions

diff --git a/src/ffmpeg_utils.c b/src/ffmpeg_utils.c
index ce239a1..fc4e4ed 100644
--- a/src/ffmpeg_utils.c
+++ b/src/ffmpeg_utils.c
@@ -1,7 +1,10 @@
 #include "../include/ffmpeg_utils.h"
+#include "../include/log.h"
 
 #include <string.h>
 #include <libavutil/error.h>
+#include <libavutil/opt.h>
+#include <libavformat/avformat.h>
 
 static _Thread_local char av_error_buffer[AV_ERROR_MAX_STRING_SIZE];
 
@@ -10,3 +13,28 @@ const char* gsr_av_error_to_string(int err) {
         strcpy(av_error_buffer, "Unknown error");
     return av_error_buffer;
 }
+
+void gsr_av_format_context_mark_packet_written(AVFormatContext *av_format_context) {
+    av_format_context->opaque = (void*)1;
+}
+
+static bool av_format_context_uses_hybrid_fragmented(AVFormatContext *av_format_context) {
+    if(LIBAVFORMAT_VERSION_INT < AV_VERSION_INT(62, 6, 101))
+        return false;
+
+    const AVOption *opt = av_opt_find(av_format_context->priv_data, "movflags", NULL, 0, 0);
+    if(!opt || !opt->unit)
+        return false;
+
+    return av_opt_find(av_format_context->priv_data, "hybrid_fragmented", opt->unit, 0, 0) != NULL;
+}
+
+int gsr_av_format_context_write_trailer(AVFormatContext *av_format_context) {
+    const bool packet_written = av_format_context->opaque != NULL;
+    if(!packet_written && av_format_context_uses_hybrid_fragmented(av_format_context)) {
+        gsr_log(GSR_LOG_LEVEL_WARNING, "not finalizing the video file because it has no video/audio data");
+        return 0;
+    }
+
+    return av_write_trailer(av_format_context);
+}