On Sun, 29 Jan 2017, Peter Große wrote:
The dash_write function drops data, if no IOContext is initialized.
Since the mp4 muxer is used in "frag_custom" mode, data is only
written when calling av_write_frame(NULL) explicitly and thus
there will be no data loss.
To add support for webm as subordinate muxer, which doesn't have
such a mode, a dynamic buffer is required to provide an always
initialized IOContext.
Signed-off-by: Peter Große <[email protected]>
---
v2:
* fix mp4 init segment handling
* reword commit message
---
libavformat/dashenc.c | 60 ++++++++++++++++++++++++++++++---------------------
1 file changed, 35 insertions(+), 25 deletions(-)
diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
index 4116fc8..d5bf275 100644
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@@ -67,11 +67,10 @@ typedef struct AdaptationSet {
typedef struct OutputStream {
AVFormatContext *ctx;
int ctx_inited, as_idx;
- uint8_t iobuf[32768];
AVIOContext *out;
int packets_written;
char initfile[1024];
- int64_t init_start_pos;
+ int64_t init_start_pos, pos;
int init_range_length;
int nb_segments, segments_size, segment_index;
Segment **segments;
@@ -107,14 +106,6 @@ typedef struct DASHContext {
const char *utc_timing_url;
} DASHContext;
-static int dash_write(void *opaque, uint8_t *buf, int buf_size)
-{
- OutputStream *os = opaque;
- if (os->out)
- avio_write(os->out, buf, buf_size);
- return buf_size;
-}
-
// RFC 6381
static void set_codec_str(AVFormatContext *s, AVCodecParameters *par,
char *str, int size)
@@ -181,6 +172,27 @@ static void set_codec_str(AVFormatContext *s,
AVCodecParameters *par,
}
}
+static int flush_dynbuf(OutputStream *os, int *range_length)
+{
+ uint8_t *buffer;
+
+ if (!os->ctx->pb) {
+ return AVERROR(EINVAL);
+ }
+
+ // flush
+ av_write_frame(os->ctx, NULL);
+ avio_flush(os->ctx->pb);
+
+ // write out to file
+ *range_length = avio_close_dyn_buf(os->ctx->pb, &buffer);
+ avio_write(os->out, buffer, *range_length);
+ av_free(buffer);
+
+ // re-open buffer
+ return avio_open_dyn_buf(&os->ctx->pb);
+}
Sorry for not noticing in the previous round, but... If avio_open_dyn_buf
fails, it will not set the pointer to NULL, so in that case, we'd end up
with a dangling pointer in os->ctx->pb and end up with a double free
later.
The rest of the patch seems fine. No need to repost just for this, I can
add the necessary os->ctx->pb = NULL before pushing.
// Martin
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