libavformat/webm_chunk: Option to specify HTTP header

Add an option to specify HTTP header in the WebM Chunk Muxer (this
works the same way as the 'method' parameter in the HLS muxer).
Signed-off-by: Vignesh Venkatasubramanian <vigneshv@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/webm_chunk.c

@@ -50,6 +50,7 @@ typedef struct WebMChunkContext {
     char *header_filename;
     int chunk_duration;
     int chunk_index;
+    char *http_method;
     uint64_t duration_written;
     int prev_pts;
     AVOutputFormat *oformat;
@@ -112,6 +113,7 @@ static int webm_chunk_write_header(AVFormatContext *s)
     AVFormatContext *oc = NULL;
     int ret;
     int i;
+    AVDictionary *options = NULL;
 
     // DASH Streams can only have either one track per file.
     if (s->nb_streams != 1) { return AVERROR_INVALIDDATA; }
@@ -128,7 +130,10 @@ static int webm_chunk_write_header(AVFormatContext *s)
     ret = get_chunk_filename(s, 1, oc->filename);
     if (ret < 0)
         return ret;
-    ret = s->io_open(s, &oc->pb, oc->filename, AVIO_FLAG_WRITE, NULL);
+    if (wc->http_method)
+        av_dict_set(&options, "method", wc->http_method, 0);
+    ret = s->io_open(s, &oc->pb, oc->filename, AVIO_FLAG_WRITE, &options);
+    av_dict_free(&options);
     if (ret < 0)
         return ret;
 
@@ -166,6 +171,7 @@ static int chunk_end(AVFormatContext *s)
     uint8_t *buffer;
     AVIOContext *pb;
     char filename[MAX_FILENAME_SIZE];
+    AVDictionary *options = NULL;
 
     if (wc->chunk_start_index == wc->chunk_index)
         return 0;
@@ -175,13 +181,16 @@ static int chunk_end(AVFormatContext *s)
     ret = get_chunk_filename(s, 0, filename);
     if (ret < 0)
         goto fail;
-    ret = s->io_open(s, &pb, filename, AVIO_FLAG_WRITE, NULL);
+    if (wc->http_method)
+        av_dict_set(&options, "method", wc->http_method, 0);
+    ret = s->io_open(s, &pb, filename, AVIO_FLAG_WRITE, &options);
     if (ret < 0)
         goto fail;
     avio_write(pb, buffer, buffer_size);
     ff_format_io_close(s, &pb);
     oc->pb = NULL;
 fail:
+    av_dict_free(&options);
     av_free(buffer);
     return (ret < 0) ? ret : 0;
 }
@@ -243,6 +252,7 @@ static const AVOption options[] = {
     { "chunk_start_index",  "start index of the chunk", OFFSET(chunk_start_index), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
     { "header", "filename of the header where the initialization data will be written", OFFSET(header_filename), AV_OPT_TYPE_STRING, { 0 }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
     { "audio_chunk_duration", "duration of each chunk in milliseconds", OFFSET(chunk_duration), AV_OPT_TYPE_INT, {.i64 = 5000}, 0, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
+    { "method", "set the HTTP method", OFFSET(http_method), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0, AV_OPT_FLAG_ENCODING_PARAM },
     { NULL },
 };