path: root/stream/stream.h
diff options
authorwm4 <wm4@nowhere>2013-05-24 23:20:09 +0200
committerwm4 <wm4@nowhere>2013-06-16 22:05:09 +0200
commitd5ad9a8f60779ec41a3213f91c39d8f48d1296bc (patch)
tree75213bc5d476fc4ff9d8b45ba61aff5912d504e0 /stream/stream.h
parent7c4202b863752e5903c76231420d9b391a0961e1 (diff)
stream: add stream_unread_buffer()
demux_lavf probes up to 2 MB of data in the worst case. When the ffmpeg demuxer is actually opened, the stream is seeked back to 0, and the previously read data is thrown away. This wasn't a problem for playback of local files, but it's less than ideal for playing from slow media (like web streams), and breaks completely if the media is not seekable (pipes, some web streams). This new function is intended to allow fixing this. demux_lavf will use it to put the read probe data back into the buffer. The simplest way of implementing this function is by making it transparently extend the normal stream buffer. This makes sure no existing code is broken by new weird special cases. For simplicity and to avoid possible performance loss due to extra dereferencing when accessing the buffer, we just extend the static buffer from 8 KB to 2 MB. Normally, most of these 2 MB will stay uncommitted, so there's no associated waste of memory. If demux_lavf really reads all 2 MB, the memory will be committed and stay unused, though.
Diffstat (limited to 'stream/stream.h')
1 files changed, 7 insertions, 3 deletions
diff --git a/stream/stream.h b/stream/stream.h
index 43ed6280bf..12ef430b28 100644
--- a/stream/stream.h
+++ b/stream/stream.h
@@ -58,6 +58,9 @@
#define STREAM_MAX_SECTOR_SIZE (8 * 1024)
+// Max buffer for initial probe.
+#define STREAM_MAX_BUFFER_SIZE (2 * 1024 * 1024)
/// atm it will always use mode == STREAM_READ
/// streams that use the new api should check the mode at open
#define STREAM_READ 0
@@ -184,14 +187,14 @@ typedef struct stream {
char *lavf_type; // name of expected demuxer type for lavf
struct MPOpts *opts;
streaming_ctrl_t *streaming_ctrl;
- unsigned char buffer[STREAM_BUFFER_SIZE >
FILE *capture_file;
char *capture_filename;
struct stream *uncached_stream;
+ // Includes additional padding in case sizes get rounded up by sector size.
+ unsigned char buffer[];
} stream_t;
@@ -199,6 +202,7 @@ typedef struct stream {
int stream_fill_buffer(stream_t *s);
+void stream_unread_buffer(stream_t *s, void *buffer, size_t buffer_size);
void stream_set_capture_file(stream_t *s, const char *filename);
void stream_capture_write(stream_t *s);