gstreamer/ext/hls/gsthlsdemux.c
Alex Ashley 0bdf13c36a hlsdemux: Fix dereferencing of NULL pointer
On some live HLS streams, gst_hls_demux_switch_playlist causes
assertion failures because it tried to dereference a NULL fragment.
This is because g_queue_peek_tail sometimes was returning NULL and
this case was not being checked.

This patch does two things:
* move the g_queue_peek_tail inside the semaphore protection
* check if q_queue_peek_tail returns NULL

https://bugzilla.gnome.org/show_bug.cgi?id=708849
2013-09-28 13:14:01 +02:00

1370 lines
42 KiB
C

/* GStreamer
* Copyright (C) 2010 Marc-Andre Lureau <marcandre.lureau@gmail.com>
* Copyright (C) 2010 Andoni Morales Alastruey <ylatuya@gmail.com>
* Copyright (C) 2011, Hewlett-Packard Development Company, L.P.
* Author: Youness Alaoui <youness.alaoui@collabora.co.uk>, Collabora Ltd.
* Author: Sebastian Dröge <sebastian.droege@collabora.co.uk>, Collabora Ltd.
*
* Gsthlsdemux.c:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:element-hlsdemux
*
* HTTP Live Streaming demuxer element.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch souphttpsrc location=http://devimages.apple.com/iphone/samples/bipbop/gear4/prog_index.m3u8 ! hlsdemux ! decodebin2 ! videoconvert ! videoscale ! autovideosink
* ]|
* </refsect2>
*
* Last reviewed on 2010-10-07
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
/* FIXME 0.11: suppress warnings for deprecated API such as GStaticRecMutex
* with newer GLib versions (>= 2.31.0) */
#define GLIB_DISABLE_DEPRECATION_WARNINGS
#include <string.h>
#include <gst/glib-compat-private.h>
#include <gnutls/gnutls.h>
#include <gnutls/crypto.h>
#include "gsthlsdemux.h"
static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src_%u",
GST_PAD_SRC,
GST_PAD_SOMETIMES,
GST_STATIC_CAPS_ANY);
static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("application/x-hls"));
GST_DEBUG_CATEGORY_STATIC (gst_hls_demux_debug);
#define GST_CAT_DEFAULT gst_hls_demux_debug
enum
{
PROP_0,
PROP_FRAGMENTS_CACHE,
PROP_BITRATE_LIMIT,
PROP_CONNECTION_SPEED,
PROP_LAST
};
static const float update_interval_factor[] = { 1, 0.5, 1.5, 3 };
#define DEFAULT_FRAGMENTS_CACHE 3
#define DEFAULT_FAILED_COUNT 3
#define DEFAULT_BITRATE_LIMIT 0.8
#define DEFAULT_CONNECTION_SPEED 0
/* GObject */
static void gst_hls_demux_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_hls_demux_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static void gst_hls_demux_dispose (GObject * obj);
/* GstElement */
static GstStateChangeReturn
gst_hls_demux_change_state (GstElement * element, GstStateChange transition);
/* GstHLSDemux */
static GstFlowReturn gst_hls_demux_chain (GstPad * pad, GstObject * parent,
GstBuffer * buf);
static gboolean gst_hls_demux_sink_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static gboolean gst_hls_demux_src_event (GstPad * pad, GstObject * parent,
GstEvent * event);
static gboolean gst_hls_demux_src_query (GstPad * pad, GstObject * parent,
GstQuery * query);
static void gst_hls_demux_stream_loop (GstHLSDemux * demux);
static void gst_hls_demux_updates_loop (GstHLSDemux * demux);
static void gst_hls_demux_stop (GstHLSDemux * demux);
static void gst_hls_demux_pause_tasks (GstHLSDemux * demux, gboolean caching);
static gboolean gst_hls_demux_cache_fragments (GstHLSDemux * demux);
static gboolean gst_hls_demux_schedule (GstHLSDemux * demux);
static gboolean gst_hls_demux_switch_playlist (GstHLSDemux * demux);
static gboolean gst_hls_demux_get_next_fragment (GstHLSDemux * demux,
gboolean caching);
static gboolean gst_hls_demux_update_playlist (GstHLSDemux * demux,
gboolean update);
static void gst_hls_demux_reset (GstHLSDemux * demux, gboolean dispose);
static gboolean gst_hls_demux_set_location (GstHLSDemux * demux,
const gchar * uri);
static gchar *gst_hls_src_buf_to_utf8_playlist (GstBuffer * buf);
#define gst_hls_demux_parent_class parent_class
G_DEFINE_TYPE (GstHLSDemux, gst_hls_demux, GST_TYPE_ELEMENT);
static void
gst_hls_demux_dispose (GObject * obj)
{
GstHLSDemux *demux = GST_HLS_DEMUX (obj);
if (demux->stream_task) {
if (GST_TASK_STATE (demux->stream_task) != GST_TASK_STOPPED) {
GST_DEBUG_OBJECT (demux, "Leaving streaming task");
gst_task_stop (demux->stream_task);
g_rec_mutex_lock (&demux->stream_lock);
g_rec_mutex_unlock (&demux->stream_lock);
gst_task_join (demux->stream_task);
}
gst_object_unref (demux->stream_task);
g_rec_mutex_clear (&demux->stream_lock);
demux->stream_task = NULL;
}
if (demux->updates_task) {
if (GST_TASK_STATE (demux->updates_task) != GST_TASK_STOPPED) {
GST_DEBUG_OBJECT (demux, "Leaving updates task");
demux->cancelled = TRUE;
gst_uri_downloader_cancel (demux->downloader);
gst_task_stop (demux->updates_task);
g_mutex_lock (&demux->updates_timed_lock);
GST_TASK_SIGNAL (demux->updates_task);
g_rec_mutex_lock (&demux->updates_lock);
g_rec_mutex_unlock (&demux->updates_lock);
g_mutex_unlock (&demux->updates_timed_lock);
gst_task_join (demux->updates_task);
}
gst_object_unref (demux->updates_task);
g_mutex_clear (&demux->updates_timed_lock);
g_rec_mutex_clear (&demux->updates_lock);
demux->updates_task = NULL;
}
if (demux->downloader != NULL) {
g_object_unref (demux->downloader);
demux->downloader = NULL;
}
gst_hls_demux_reset (demux, TRUE);
g_queue_free (demux->queue);
G_OBJECT_CLASS (parent_class)->dispose (obj);
}
static void
gst_hls_demux_class_init (GstHLSDemuxClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *element_class;
gobject_class = (GObjectClass *) klass;
element_class = (GstElementClass *) klass;
gobject_class->set_property = gst_hls_demux_set_property;
gobject_class->get_property = gst_hls_demux_get_property;
gobject_class->dispose = gst_hls_demux_dispose;
g_object_class_install_property (gobject_class, PROP_FRAGMENTS_CACHE,
g_param_spec_uint ("fragments-cache", "Fragments cache",
"Number of fragments needed to be cached to start playing",
2, G_MAXUINT, DEFAULT_FRAGMENTS_CACHE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_BITRATE_LIMIT,
g_param_spec_float ("bitrate-limit",
"Bitrate limit in %",
"Limit of the available bitrate to use when switching to alternates.",
0, 1, DEFAULT_BITRATE_LIMIT,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_CONNECTION_SPEED,
g_param_spec_uint ("connection-speed", "Connection Speed",
"Network connection speed in kbps (0 = unknown)",
0, G_MAXUINT / 1000, DEFAULT_CONNECTION_SPEED,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
element_class->change_state = GST_DEBUG_FUNCPTR (gst_hls_demux_change_state);
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&srctemplate));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&sinktemplate));
gst_element_class_set_static_metadata (element_class,
"HLS Demuxer",
"Demuxer/URIList",
"HTTP Live Streaming demuxer",
"Marc-Andre Lureau <marcandre.lureau@gmail.com>\n"
"Andoni Morales Alastruey <ylatuya@gmail.com>");
GST_DEBUG_CATEGORY_INIT (gst_hls_demux_debug, "hlsdemux", 0,
"hlsdemux element");
}
static void
gst_hls_demux_init (GstHLSDemux * demux)
{
/* sink pad */
demux->sinkpad = gst_pad_new_from_static_template (&sinktemplate, "sink");
gst_pad_set_chain_function (demux->sinkpad,
GST_DEBUG_FUNCPTR (gst_hls_demux_chain));
gst_pad_set_event_function (demux->sinkpad,
GST_DEBUG_FUNCPTR (gst_hls_demux_sink_event));
gst_element_add_pad (GST_ELEMENT (demux), demux->sinkpad);
/* Downloader */
demux->downloader = gst_uri_downloader_new ();
demux->do_typefind = TRUE;
/* Properties */
demux->fragments_cache = DEFAULT_FRAGMENTS_CACHE;
demux->bitrate_limit = DEFAULT_BITRATE_LIMIT;
demux->connection_speed = DEFAULT_CONNECTION_SPEED;
demux->queue = g_queue_new ();
/* Updates task */
g_rec_mutex_init (&demux->updates_lock);
demux->updates_task =
gst_task_new ((GstTaskFunction) gst_hls_demux_updates_loop, demux, NULL);
gst_task_set_lock (demux->updates_task, &demux->updates_lock);
g_mutex_init (&demux->updates_timed_lock);
/* Streaming task */
g_rec_mutex_init (&demux->stream_lock);
demux->stream_task =
gst_task_new ((GstTaskFunction) gst_hls_demux_stream_loop, demux, NULL);
gst_task_set_lock (demux->stream_task, &demux->stream_lock);
demux->have_group_id = FALSE;
demux->group_id = G_MAXUINT;
}
static void
gst_hls_demux_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstHLSDemux *demux = GST_HLS_DEMUX (object);
switch (prop_id) {
case PROP_FRAGMENTS_CACHE:
demux->fragments_cache = g_value_get_uint (value);
break;
case PROP_BITRATE_LIMIT:
demux->bitrate_limit = g_value_get_float (value);
break;
case PROP_CONNECTION_SPEED:
demux->connection_speed = g_value_get_uint (value) * 1000;
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_hls_demux_get_property (GObject * object, guint prop_id, GValue * value,
GParamSpec * pspec)
{
GstHLSDemux *demux = GST_HLS_DEMUX (object);
switch (prop_id) {
case PROP_FRAGMENTS_CACHE:
g_value_set_uint (value, demux->fragments_cache);
break;
case PROP_BITRATE_LIMIT:
g_value_set_float (value, demux->bitrate_limit);
break;
case PROP_CONNECTION_SPEED:
g_value_set_uint (value, demux->connection_speed / 1000);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static GstStateChangeReturn
gst_hls_demux_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret;
GstHLSDemux *demux = GST_HLS_DEMUX (element);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_PAUSED:
gst_hls_demux_reset (demux, FALSE);
gst_uri_downloader_reset (demux->downloader);
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_PAUSED_TO_READY:
demux->cancelled = TRUE;
gst_hls_demux_stop (demux);
gst_task_join (demux->stream_task);
gst_hls_demux_reset (demux, FALSE);
break;
default:
break;
}
return ret;
}
static gboolean
gst_hls_demux_src_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstHLSDemux *demux;
demux = GST_HLS_DEMUX (parent);
switch (event->type) {
case GST_EVENT_SEEK:
{
gdouble rate;
GstFormat format;
GstSeekFlags flags;
GstSeekType start_type, stop_type;
gint64 start, stop;
GList *walk;
GstClockTime position, current_pos, target_pos;
gint current_sequence;
GstM3U8MediaFile *file;
GST_INFO_OBJECT (demux, "Received GST_EVENT_SEEK");
if (gst_m3u8_client_is_live (demux->client)) {
GST_WARNING_OBJECT (demux, "Received seek event for live stream");
return FALSE;
}
gst_event_parse_seek (event, &rate, &format, &flags, &start_type, &start,
&stop_type, &stop);
if (format != GST_FORMAT_TIME)
return FALSE;
GST_DEBUG_OBJECT (demux, "seek event, rate: %f start: %" GST_TIME_FORMAT
" stop: %" GST_TIME_FORMAT, rate, GST_TIME_ARGS (start),
GST_TIME_ARGS (stop));
GST_M3U8_CLIENT_LOCK (demux->client);
file = GST_M3U8_MEDIA_FILE (demux->client->current->files->data);
current_sequence = file->sequence;
current_pos = 0;
target_pos = (GstClockTime) start;
for (walk = demux->client->current->files; walk; walk = walk->next) {
file = walk->data;
current_sequence = file->sequence;
if (current_pos <= target_pos
&& target_pos < current_pos + file->duration) {
break;
}
current_pos += file->duration;
}
GST_M3U8_CLIENT_UNLOCK (demux->client);
if (walk == NULL) {
GST_WARNING_OBJECT (demux, "Could not find seeked fragment");
return FALSE;
}
if (flags & GST_SEEK_FLAG_FLUSH) {
GST_DEBUG_OBJECT (demux, "sending flush start");
gst_pad_push_event (demux->srcpad, gst_event_new_flush_start ());
}
demux->cancelled = TRUE;
gst_task_pause (demux->stream_task);
gst_uri_downloader_cancel (demux->downloader);
gst_task_stop (demux->updates_task);
g_mutex_lock (&demux->updates_timed_lock);
GST_TASK_SIGNAL (demux->updates_task);
g_mutex_unlock (&demux->updates_timed_lock);
g_rec_mutex_lock (&demux->updates_lock);
g_rec_mutex_unlock (&demux->updates_lock);
gst_task_pause (demux->stream_task);
/* wait for streaming to finish */
g_rec_mutex_lock (&demux->stream_lock);
demux->need_cache = TRUE;
while (!g_queue_is_empty (demux->queue)) {
GstFragment *fragment = g_queue_pop_head (demux->queue);
g_object_unref (fragment);
}
g_queue_clear (demux->queue);
GST_M3U8_CLIENT_LOCK (demux->client);
GST_DEBUG_OBJECT (demux, "seeking to sequence %d", current_sequence);
demux->client->sequence = current_sequence;
gst_m3u8_client_get_current_position (demux->client, &position);
demux->position_shift = start - position;
demux->need_segment = TRUE;
GST_M3U8_CLIENT_UNLOCK (demux->client);
if (flags & GST_SEEK_FLAG_FLUSH) {
GST_DEBUG_OBJECT (demux, "sending flush stop");
gst_pad_push_event (demux->srcpad, gst_event_new_flush_stop (TRUE));
}
demux->cancelled = FALSE;
gst_uri_downloader_reset (demux->downloader);
gst_task_start (demux->stream_task);
g_rec_mutex_unlock (&demux->stream_lock);
return TRUE;
}
default:
break;
}
return gst_pad_event_default (pad, parent, event);
}
static gboolean
gst_hls_demux_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstHLSDemux *demux;
GstQuery *query;
gboolean ret;
gchar *uri;
demux = GST_HLS_DEMUX (parent);
switch (event->type) {
case GST_EVENT_EOS:{
gchar *playlist = NULL;
if (demux->playlist == NULL) {
GST_WARNING_OBJECT (demux, "Received EOS without a playlist.");
break;
}
GST_DEBUG_OBJECT (demux,
"Got EOS on the sink pad: main playlist fetched");
query = gst_query_new_uri ();
ret = gst_pad_peer_query (demux->sinkpad, query);
if (ret) {
gst_query_parse_uri_redirection (query, &uri);
if (uri == NULL)
gst_query_parse_uri (query, &uri);
gst_hls_demux_set_location (demux, uri);
g_free (uri);
}
gst_query_unref (query);
playlist = gst_hls_src_buf_to_utf8_playlist (demux->playlist);
demux->playlist = NULL;
if (playlist == NULL) {
GST_WARNING_OBJECT (demux, "Error validating first playlist.");
} else if (!gst_m3u8_client_update (demux->client, playlist)) {
/* In most cases, this will happen if we set a wrong url in the
* source element and we have received the 404 HTML response instead of
* the playlist */
GST_ELEMENT_ERROR (demux, STREAM, DECODE, ("Invalid playlist."),
(NULL));
return FALSE;
}
if (!ret && gst_m3u8_client_is_live (demux->client)) {
GST_ELEMENT_ERROR (demux, RESOURCE, NOT_FOUND,
("Failed querying the playlist uri, "
"required for live sources."), (NULL));
return FALSE;
}
gst_task_start (demux->stream_task);
gst_event_unref (event);
return TRUE;
}
case GST_EVENT_SEGMENT:
/* Swallow newsegments, we'll push our own */
gst_event_unref (event);
return TRUE;
default:
break;
}
return gst_pad_event_default (pad, parent, event);
}
static gboolean
gst_hls_demux_src_query (GstPad * pad, GstObject * parent, GstQuery * query)
{
GstHLSDemux *hlsdemux;
gboolean ret = FALSE;
if (query == NULL)
return FALSE;
hlsdemux = GST_HLS_DEMUX (parent);
switch (query->type) {
case GST_QUERY_DURATION:{
GstClockTime duration = -1;
GstFormat fmt;
gst_query_parse_duration (query, &fmt, NULL);
if (fmt == GST_FORMAT_TIME) {
duration = gst_m3u8_client_get_duration (hlsdemux->client);
if (GST_CLOCK_TIME_IS_VALID (duration) && duration > 0) {
gst_query_set_duration (query, GST_FORMAT_TIME, duration);
ret = TRUE;
}
}
GST_INFO_OBJECT (hlsdemux, "GST_QUERY_DURATION returns %s with duration %"
GST_TIME_FORMAT, ret ? "TRUE" : "FALSE", GST_TIME_ARGS (duration));
break;
}
case GST_QUERY_URI:
if (hlsdemux->client) {
/* FIXME: Do we answer with the variant playlist, with the current
* playlist or the the uri of the least downlowaded fragment? */
gst_query_set_uri (query, gst_m3u8_client_get_uri (hlsdemux->client));
ret = TRUE;
}
break;
case GST_QUERY_SEEKING:{
GstFormat fmt;
gint64 stop = -1;
gst_query_parse_seeking (query, &fmt, NULL, NULL, NULL);
GST_INFO_OBJECT (hlsdemux, "Received GST_QUERY_SEEKING with format %d",
fmt);
if (fmt == GST_FORMAT_TIME) {
GstClockTime duration;
duration = gst_m3u8_client_get_duration (hlsdemux->client);
if (GST_CLOCK_TIME_IS_VALID (duration) && duration > 0)
stop = duration;
gst_query_set_seeking (query, fmt,
!gst_m3u8_client_is_live (hlsdemux->client), 0, stop);
ret = TRUE;
GST_INFO_OBJECT (hlsdemux, "GST_QUERY_SEEKING returning with stop : %"
GST_TIME_FORMAT, GST_TIME_ARGS (stop));
}
break;
}
default:
/* Don't fordward queries upstream because of the special nature of this
* "demuxer", which relies on the upstream element only to be fed with the
* first playlist */
break;
}
return ret;
}
static GstFlowReturn
gst_hls_demux_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
{
GstHLSDemux *demux = GST_HLS_DEMUX (parent);
if (demux->playlist == NULL)
demux->playlist = buf;
else
demux->playlist = gst_buffer_append (demux->playlist, buf);
return GST_FLOW_OK;
}
static void
gst_hls_demux_pause_tasks (GstHLSDemux * demux, gboolean caching)
{
if (GST_TASK_STATE (demux->updates_task) != GST_TASK_STOPPED) {
demux->cancelled = TRUE;
gst_uri_downloader_cancel (demux->downloader);
gst_task_pause (demux->updates_task);
if (!caching)
g_mutex_lock (&demux->updates_timed_lock);
GST_TASK_SIGNAL (demux->updates_task);
if (!caching)
g_mutex_unlock (&demux->updates_timed_lock);
}
if (GST_TASK_STATE (demux->stream_task) != GST_TASK_STOPPED) {
demux->stop_stream_task = TRUE;
gst_task_pause (demux->stream_task);
}
}
static void
gst_hls_demux_stop (GstHLSDemux * demux)
{
gst_uri_downloader_cancel (demux->downloader);
if (GST_TASK_STATE (demux->updates_task) != GST_TASK_STOPPED) {
demux->cancelled = TRUE;
gst_uri_downloader_cancel (demux->downloader);
gst_task_stop (demux->updates_task);
g_mutex_lock (&demux->updates_timed_lock);
GST_TASK_SIGNAL (demux->updates_task);
g_mutex_unlock (&demux->updates_timed_lock);
g_rec_mutex_lock (&demux->updates_lock);
g_rec_mutex_unlock (&demux->updates_lock);
}
if (GST_TASK_STATE (demux->stream_task) != GST_TASK_STOPPED) {
demux->stop_stream_task = TRUE;
gst_task_stop (demux->stream_task);
g_rec_mutex_lock (&demux->stream_lock);
g_rec_mutex_unlock (&demux->stream_lock);
}
}
static void
switch_pads (GstHLSDemux * demux, GstCaps * newcaps)
{
GstPad *oldpad = demux->srcpad;
GstEvent *event;
gchar *stream_id;
GST_DEBUG ("Switching pads (oldpad:%p) with caps: %" GST_PTR_FORMAT, oldpad,
newcaps);
/* First create and activate new pad */
demux->srcpad = gst_pad_new_from_static_template (&srctemplate, NULL);
gst_pad_set_event_function (demux->srcpad,
GST_DEBUG_FUNCPTR (gst_hls_demux_src_event));
gst_pad_set_query_function (demux->srcpad,
GST_DEBUG_FUNCPTR (gst_hls_demux_src_query));
gst_pad_set_element_private (demux->srcpad, demux);
gst_pad_set_active (demux->srcpad, TRUE);
stream_id =
gst_pad_create_stream_id (demux->srcpad, GST_ELEMENT_CAST (demux), NULL);
event = gst_pad_get_sticky_event (demux->sinkpad, GST_EVENT_STREAM_START, 0);
if (event) {
if (gst_event_parse_group_id (event, &demux->group_id))
demux->have_group_id = TRUE;
else
demux->have_group_id = FALSE;
gst_event_unref (event);
} else if (!demux->have_group_id) {
demux->have_group_id = TRUE;
demux->group_id = gst_util_group_id_next ();
}
event = gst_event_new_stream_start (stream_id);
if (demux->have_group_id)
gst_event_set_group_id (event, demux->group_id);
gst_pad_push_event (demux->srcpad, event);
g_free (stream_id);
gst_pad_set_caps (demux->srcpad, newcaps);
gst_element_add_pad (GST_ELEMENT (demux), demux->srcpad);
gst_element_no_more_pads (GST_ELEMENT (demux));
if (oldpad) {
/* Push out EOS */
gst_pad_push_event (oldpad, gst_event_new_eos ());
gst_pad_set_active (oldpad, FALSE);
gst_element_remove_pad (GST_ELEMENT (demux), oldpad);
}
}
static void
gst_hls_demux_stream_loop (GstHLSDemux * demux)
{
GstFragment *fragment;
GstBuffer *buf;
GstFlowReturn ret;
GstCaps *bufcaps, *srccaps = NULL;
/* Loop for the source pad task. The task is started when we have
* received the main playlist from the source element. It tries first to
* cache the first fragments and then it waits until it has more data in the
* queue. This task is woken up when we push a new fragment to the queue or
* when we reached the end of the playlist */
GST_DEBUG_OBJECT (demux, "Enter task");
if (G_UNLIKELY (demux->need_cache)) {
if (!gst_hls_demux_cache_fragments (demux))
goto cache_error;
/* we can start now the updates thread (only if on playing) */
gst_task_start (demux->updates_task);
GST_INFO_OBJECT (demux, "First fragments cached successfully");
}
if (g_queue_is_empty (demux->queue)) {
if (demux->end_of_playlist)
goto end_of_playlist;
goto pause_task;
}
fragment = g_queue_pop_head (demux->queue);
buf = gst_fragment_get_buffer (fragment);
/* Figure out if we need to create/switch pads */
if (G_LIKELY (demux->srcpad))
srccaps = gst_pad_get_current_caps (demux->srcpad);
bufcaps = gst_fragment_get_caps (fragment);
if (G_UNLIKELY (!srccaps || !gst_caps_is_equal_fixed (bufcaps, srccaps)
|| demux->need_segment)) {
switch_pads (demux, bufcaps);
demux->need_segment = TRUE;
}
gst_caps_unref (bufcaps);
if (G_LIKELY (srccaps))
gst_caps_unref (srccaps);
g_object_unref (fragment);
if (demux->need_segment) {
GstSegment segment;
GstClockTime start = GST_BUFFER_PTS (buf);
start += demux->position_shift;
/* And send a newsegment */
GST_DEBUG_OBJECT (demux, "Sending new-segment. segment start:%"
GST_TIME_FORMAT, GST_TIME_ARGS (start));
gst_segment_init (&segment, GST_FORMAT_TIME);
segment.start = start;
segment.time = start;
gst_pad_push_event (demux->srcpad, gst_event_new_segment (&segment));
demux->need_segment = FALSE;
demux->position_shift = 0;
}
GST_DEBUG_OBJECT (demux, "Pushing buffer %p", buf);
ret = gst_pad_push (demux->srcpad, buf);
if (ret != GST_FLOW_OK)
goto error_pushing;
GST_DEBUG_OBJECT (demux, "Pushed buffer");
return;
end_of_playlist:
{
GST_DEBUG_OBJECT (demux, "Reached end of playlist, sending EOS");
gst_pad_push_event (demux->srcpad, gst_event_new_eos ());
gst_hls_demux_pause_tasks (demux, FALSE);
return;
}
cache_error:
{
gst_task_pause (demux->stream_task);
if (!demux->cancelled) {
GST_ELEMENT_ERROR (demux, RESOURCE, NOT_FOUND,
("Could not cache the first fragments"), (NULL));
gst_hls_demux_pause_tasks (demux, FALSE);
}
return;
}
error_pushing:
{
if (ret == GST_FLOW_NOT_LINKED || ret < GST_FLOW_EOS) {
GST_ELEMENT_ERROR (demux, STREAM, FAILED, (NULL),
("stream stopped, reason %s", gst_flow_get_name (ret)));
gst_pad_push_event (demux->srcpad, gst_event_new_eos ());
} else {
GST_DEBUG_OBJECT (demux, "stream stopped, reason %s",
gst_flow_get_name (ret));
}
gst_hls_demux_pause_tasks (demux, FALSE);
return;
}
pause_task:
{
GST_DEBUG_OBJECT (demux, "Pause task");
gst_task_pause (demux->stream_task);
return;
}
}
static void
gst_hls_demux_reset (GstHLSDemux * demux, gboolean dispose)
{
demux->need_cache = TRUE;
demux->end_of_playlist = FALSE;
demux->cancelled = FALSE;
demux->do_typefind = TRUE;
if (demux->input_caps) {
gst_caps_unref (demux->input_caps);
demux->input_caps = NULL;
}
if (demux->playlist) {
gst_buffer_unref (demux->playlist);
demux->playlist = NULL;
}
if (demux->client) {
gst_m3u8_client_free (demux->client);
demux->client = NULL;
}
if (!dispose) {
demux->client = gst_m3u8_client_new ("");
}
while (!g_queue_is_empty (demux->queue)) {
GstFragment *fragment = g_queue_pop_head (demux->queue);
g_object_unref (fragment);
}
g_queue_clear (demux->queue);
demux->position_shift = 0;
demux->need_segment = TRUE;
demux->have_group_id = FALSE;
demux->group_id = G_MAXUINT;
}
static gboolean
gst_hls_demux_set_location (GstHLSDemux * demux, const gchar * uri)
{
if (demux->client)
gst_m3u8_client_free (demux->client);
demux->client = gst_m3u8_client_new (uri);
GST_INFO_OBJECT (demux, "Changed location: %s", uri);
return TRUE;
}
void
gst_hls_demux_updates_loop (GstHLSDemux * demux)
{
/* Loop for the updates. It's started when the first fragments are cached and
* schedules the next update of the playlist (for lives sources) and the next
* update of fragments. When a new fragment is downloaded, it compares the
* download time with the next scheduled update to check if we can or should
* switch to a different bitrate */
/* block until the next scheduled update or the signal to quit this thread */
g_mutex_lock (&demux->updates_timed_lock);
GST_DEBUG_OBJECT (demux, "Started updates task");
while (TRUE) {
if (demux->cancelled)
goto quit;
/* schedule the next update */
gst_hls_demux_schedule (demux);
/* block until the next scheduled update or the signal to quit this thread */
GST_DEBUG_OBJECT (demux, "Waiting");
if (g_cond_timed_wait (GST_TASK_GET_COND (demux->updates_task),
&demux->updates_timed_lock, &demux->next_update)) {
GST_DEBUG_OBJECT (demux, "Unlocked");
goto quit;
}
GST_DEBUG_OBJECT (demux, "Continue");
if (demux->cancelled)
goto quit;
/* update the playlist for live sources */
if (gst_m3u8_client_is_live (demux->client)) {
if (!gst_hls_demux_update_playlist (demux, TRUE)) {
if (demux->cancelled)
goto quit;
demux->client->update_failed_count++;
if (demux->client->update_failed_count < DEFAULT_FAILED_COUNT) {
GST_WARNING_OBJECT (demux, "Could not update the playlist");
continue;
} else {
GST_ELEMENT_ERROR (demux, RESOURCE, NOT_FOUND,
("Could not update the playlist"), (NULL));
goto error;
}
}
}
/* if it's a live source and the playlist couldn't be updated, there aren't
* more fragments in the playlist, so we just wait for the next schedulled
* update */
if (gst_m3u8_client_is_live (demux->client) &&
demux->client->update_failed_count > 0) {
GST_WARNING_OBJECT (demux,
"The playlist hasn't been updated, failed count is %d",
demux->client->update_failed_count);
continue;
}
if (demux->cancelled)
goto quit;
/* fetch the next fragment */
if (g_queue_is_empty (demux->queue)) {
GST_DEBUG_OBJECT (demux, "queue empty, get next fragment");
if (!gst_hls_demux_get_next_fragment (demux, FALSE)) {
if (demux->cancelled) {
goto quit;
} else if (!demux->end_of_playlist && !demux->cancelled) {
demux->client->update_failed_count++;
if (demux->client->update_failed_count < DEFAULT_FAILED_COUNT) {
GST_WARNING_OBJECT (demux, "Could not fetch the next fragment");
continue;
} else {
GST_ELEMENT_ERROR (demux, RESOURCE, NOT_FOUND,
("Could not fetch the next fragment"), (NULL));
goto error;
}
}
} else {
demux->client->update_failed_count = 0;
if (demux->cancelled)
goto quit;
/* try to switch to another bitrate if needed */
gst_hls_demux_switch_playlist (demux);
}
}
}
quit:
{
GST_DEBUG_OBJECT (demux, "Stopped updates task");
g_mutex_unlock (&demux->updates_timed_lock);
return;
}
error:
{
GST_DEBUG_OBJECT (demux, "Stopped updates task because of error");
gst_hls_demux_pause_tasks (demux, TRUE);
g_mutex_unlock (&demux->updates_timed_lock);
}
}
static gboolean
gst_hls_demux_cache_fragments (GstHLSDemux * demux)
{
gint i;
/* If this playlist is a variant playlist, select the first one
* and update it */
if (gst_m3u8_client_has_variant_playlist (demux->client)) {
GstM3U8 *child = NULL;
if (demux->connection_speed == 0) {
GST_M3U8_CLIENT_LOCK (demux->client);
child = demux->client->main->current_variant->data;
GST_M3U8_CLIENT_UNLOCK (demux->client);
} else {
GList *tmp = gst_m3u8_client_get_playlist_for_bitrate (demux->client,
demux->connection_speed);
child = GST_M3U8 (tmp->data);
}
gst_m3u8_client_set_current (demux->client, child);
if (!gst_hls_demux_update_playlist (demux, FALSE)) {
GST_ERROR_OBJECT (demux, "Could not fetch the child playlist %s",
child->uri);
return FALSE;
}
}
if (!gst_m3u8_client_is_live (demux->client)) {
GstClockTime duration = gst_m3u8_client_get_duration (demux->client);
GST_DEBUG_OBJECT (demux, "Sending duration message : %" GST_TIME_FORMAT,
GST_TIME_ARGS (duration));
if (duration != GST_CLOCK_TIME_NONE)
gst_element_post_message (GST_ELEMENT (demux),
gst_message_new_duration_changed (GST_OBJECT (demux)));
}
/* Cache the first fragments */
for (i = 0; i < demux->fragments_cache; i++) {
gst_element_post_message (GST_ELEMENT (demux),
gst_message_new_buffering (GST_OBJECT (demux),
100 * i / demux->fragments_cache));
g_get_current_time (&demux->next_update);
if (!gst_hls_demux_get_next_fragment (demux, TRUE)) {
if (demux->end_of_playlist)
break;
if (!demux->cancelled)
GST_ERROR_OBJECT (demux, "Error caching the first fragments");
return FALSE;
}
/* make sure we stop caching fragments if something cancelled it */
if (demux->cancelled)
return FALSE;
gst_hls_demux_switch_playlist (demux);
}
gst_element_post_message (GST_ELEMENT (demux),
gst_message_new_buffering (GST_OBJECT (demux), 100));
g_get_current_time (&demux->next_update);
demux->need_cache = FALSE;
return TRUE;
}
static gchar *
gst_hls_src_buf_to_utf8_playlist (GstBuffer * buf)
{
GstMapInfo info;
gchar *playlist;
if (!gst_buffer_map (buf, &info, GST_MAP_READ))
return NULL;
if (!g_utf8_validate ((gchar *) info.data, info.size, NULL))
goto validate_error;
/* alloc size + 1 to end with a null character */
playlist = g_malloc0 (info.size + 1);
memcpy (playlist, info.data, info.size);
gst_buffer_unmap (buf, &info);
gst_buffer_unref (buf);
return playlist;
validate_error:
gst_buffer_unmap (buf, &info);
gst_buffer_unref (buf);
return NULL;
}
static gboolean
gst_hls_demux_update_playlist (GstHLSDemux * demux, gboolean update)
{
GstFragment *download;
GstBuffer *buf;
gchar *playlist;
gboolean updated = FALSE;
const gchar *uri = gst_m3u8_client_get_current_uri (demux->client);
download = gst_uri_downloader_fetch_uri (demux->downloader, uri);
if (download == NULL)
return FALSE;
buf = gst_fragment_get_buffer (download);
playlist = gst_hls_src_buf_to_utf8_playlist (buf);
g_object_unref (download);
if (playlist == NULL) {
GST_WARNING_OBJECT (demux, "Couldn't not validate playlist encoding");
return FALSE;
}
updated = gst_m3u8_client_update (demux->client, playlist);
/* If it's a live source, do not let the sequence number go beyond
* three fragments before the end of the list */
if (updated && update == FALSE && demux->client->current &&
gst_m3u8_client_is_live (demux->client)) {
guint last_sequence;
GST_M3U8_CLIENT_LOCK (demux->client);
last_sequence =
GST_M3U8_MEDIA_FILE (g_list_last (demux->client->current->
files)->data)->sequence;
if (demux->client->sequence >= last_sequence - 3) {
GST_DEBUG_OBJECT (demux, "Sequence is beyond playlist. Moving back to %d",
last_sequence - 3);
demux->need_segment = TRUE;
demux->client->sequence = last_sequence - 3;
}
GST_M3U8_CLIENT_UNLOCK (demux->client);
}
return updated;
}
static gboolean
gst_hls_demux_change_playlist (GstHLSDemux * demux, guint max_bitrate)
{
GList *previous_variant, *current_variant;
gint old_bandwidth, new_bandwidth;
/* If user specifies a connection speed never use a playlist with a bandwidth
* superior than it */
if (demux->connection_speed != 0 && max_bitrate > demux->connection_speed)
max_bitrate = demux->connection_speed;
previous_variant = demux->client->main->current_variant;
current_variant = gst_m3u8_client_get_playlist_for_bitrate (demux->client,
max_bitrate);
retry_failover_protection:
old_bandwidth = GST_M3U8 (previous_variant->data)->bandwidth;
new_bandwidth = GST_M3U8 (current_variant->data)->bandwidth;
/* Don't do anything else if the playlist is the same */
if (new_bandwidth == old_bandwidth) {
return TRUE;
}
demux->client->main->current_variant = current_variant;
GST_M3U8_CLIENT_UNLOCK (demux->client);
gst_m3u8_client_set_current (demux->client, current_variant->data);
GST_INFO_OBJECT (demux, "Client was on %dbps, max allowed is %dbps, switching"
" to bitrate %dbps", old_bandwidth, max_bitrate, new_bandwidth);
if (gst_hls_demux_update_playlist (demux, FALSE)) {
GstStructure *s;
s = gst_structure_new ("playlist",
"uri", G_TYPE_STRING, gst_m3u8_client_get_current_uri (demux->client),
"bitrate", G_TYPE_INT, new_bandwidth, NULL);
gst_element_post_message (GST_ELEMENT_CAST (demux),
gst_message_new_element (GST_OBJECT_CAST (demux), s));
} else {
GList *failover = NULL;
GST_INFO_OBJECT (demux, "Unable to update playlist. Switching back");
GST_M3U8_CLIENT_LOCK (demux->client);
failover = g_list_previous (current_variant);
if (failover && new_bandwidth == GST_M3U8 (failover->data)->bandwidth) {
current_variant = failover;
goto retry_failover_protection;
}
demux->client->main->current_variant = previous_variant;
GST_M3U8_CLIENT_UNLOCK (demux->client);
gst_m3u8_client_set_current (demux->client, previous_variant->data);
/* Try a lower bitrate (or stop if we just tried the lowest) */
if (new_bandwidth ==
GST_M3U8 (g_list_first (demux->client->main->lists)->data)->bandwidth)
return FALSE;
else
return gst_hls_demux_change_playlist (demux, new_bandwidth - 1);
}
/* Force typefinding since we might have changed media type */
demux->do_typefind = TRUE;
return TRUE;
}
static gboolean
gst_hls_demux_schedule (GstHLSDemux * demux)
{
gfloat update_factor;
gint count;
/* As defined in §6.3.4. Reloading the Playlist file:
* "If the client reloads a Playlist file and finds that it has not
* changed then it MUST wait for a period of time before retrying. The
* minimum delay is a multiple of the target duration. This multiple is
* 0.5 for the first attempt, 1.5 for the second, and 3.0 thereafter."
*/
count = demux->client->update_failed_count;
if (count < 3)
update_factor = update_interval_factor[count];
else
update_factor = update_interval_factor[3];
/* schedule the next update using the target duration field of the
* playlist */
g_time_val_add (&demux->next_update,
gst_m3u8_client_get_target_duration (demux->client)
/ GST_SECOND * G_USEC_PER_SEC * update_factor);
GST_DEBUG_OBJECT (demux, "Next update scheduled at %s",
g_time_val_to_iso8601 (&demux->next_update));
return TRUE;
}
static gboolean
gst_hls_demux_switch_playlist (GstHLSDemux * demux)
{
GTimeVal now;
GstClockTime diff;
gsize size;
gint bitrate;
GstFragment *fragment;
GstBuffer *buffer;
GST_M3U8_CLIENT_LOCK (demux->client);
fragment = g_queue_peek_tail (demux->queue);
if (!demux->client->main->lists || !fragment) {
GST_M3U8_CLIENT_UNLOCK (demux->client);
return TRUE;
}
GST_M3U8_CLIENT_UNLOCK (demux->client);
/* compare the time when the fragment was downloaded with the time when it was
* scheduled */
g_get_current_time (&now);
diff = (GST_TIMEVAL_TO_TIME (now) - GST_TIMEVAL_TO_TIME (demux->next_update));
buffer = gst_fragment_get_buffer (fragment);
size = gst_buffer_get_size (buffer);
bitrate = (size * 8) / ((double) diff / GST_SECOND);
GST_DEBUG ("Downloaded %d bytes in %" GST_TIME_FORMAT ". Bitrate is : %d",
(guint) size, GST_TIME_ARGS (diff), bitrate);
gst_buffer_unref (buffer);
return gst_hls_demux_change_playlist (demux, bitrate * demux->bitrate_limit);
}
static GstFragment *
gst_hls_demux_decrypt_fragment (GstHLSDemux * demux,
GstFragment * encrypted_fragment, const gchar * key, const guint8 * iv)
{
GstFragment *key_fragment, *ret;
GstBuffer *key_buffer, *encrypted_buffer, *decrypted_buffer;
GstMapInfo key_info, encrypted_info, decrypted_info;
gnutls_cipher_hd_t aes_ctx;
gnutls_datum_t key_d, iv_d;
gsize unpadded_size;
GST_INFO_OBJECT (demux, "Fetching key %s", key);
key_fragment = gst_uri_downloader_fetch_uri (demux->downloader, key);
if (key_fragment == NULL)
return NULL;
key_buffer = gst_fragment_get_buffer (key_fragment);
encrypted_buffer = gst_fragment_get_buffer (encrypted_fragment);
decrypted_buffer =
gst_buffer_new_allocate (NULL, gst_buffer_get_size (encrypted_buffer),
NULL);
gst_buffer_map (key_buffer, &key_info, GST_MAP_READ);
gst_buffer_map (encrypted_buffer, &encrypted_info, GST_MAP_READ);
gst_buffer_map (decrypted_buffer, &decrypted_info, GST_MAP_WRITE);
key_d.data = key_info.data;
key_d.size = 16;
iv_d.data = (unsigned char *) iv;
iv_d.size = 16;
gnutls_cipher_init (&aes_ctx, gnutls_cipher_get_id ("AES-128-CBC"), &key_d,
&iv_d);
gnutls_cipher_decrypt2 (aes_ctx, encrypted_info.data, encrypted_info.size,
decrypted_info.data, decrypted_info.size);
gnutls_cipher_deinit (aes_ctx);
/* Handle pkcs7 unpadding here */
unpadded_size =
decrypted_info.size - decrypted_info.data[decrypted_info.size - 1];
gst_buffer_unmap (decrypted_buffer, &decrypted_info);
gst_buffer_unmap (encrypted_buffer, &encrypted_info);
gst_buffer_unmap (key_buffer, &key_info);
gst_buffer_resize (decrypted_buffer, 0, unpadded_size);
gst_buffer_unref (key_buffer);
gst_buffer_unref (encrypted_buffer);
g_object_unref (key_fragment);
g_object_unref (encrypted_fragment);
ret = gst_fragment_new ();
gst_fragment_add_buffer (ret, decrypted_buffer);
ret->completed = TRUE;
return ret;
}
static gboolean
gst_hls_demux_get_next_fragment (GstHLSDemux * demux, gboolean caching)
{
GstFragment *download;
const gchar *next_fragment_uri;
GstClockTime duration;
GstClockTime timestamp;
GstBuffer *buf;
gboolean discont;
const gchar *key = NULL;
const guint8 *iv = NULL;
if (!gst_m3u8_client_get_next_fragment (demux->client, &discont,
&next_fragment_uri, &duration, &timestamp, &key, &iv)) {
GST_INFO_OBJECT (demux, "This playlist doesn't contain more fragments");
demux->end_of_playlist = TRUE;
gst_task_start (demux->stream_task);
return FALSE;
}
GST_INFO_OBJECT (demux, "Fetching next fragment %s", next_fragment_uri);
download = gst_uri_downloader_fetch_uri (demux->downloader,
next_fragment_uri);
if (download && key)
download = gst_hls_demux_decrypt_fragment (demux, download, key, iv);
if (download == NULL)
goto error;
buf = gst_fragment_get_buffer (download);
GST_BUFFER_DURATION (buf) = duration;
GST_BUFFER_PTS (buf) = timestamp;
/* We actually need to do this every time we switch bitrate */
if (G_UNLIKELY (demux->do_typefind)) {
GstCaps *caps = gst_fragment_get_caps (download);
if (!demux->input_caps || !gst_caps_is_equal (caps, demux->input_caps)) {
gst_caps_replace (&demux->input_caps, caps);
/* gst_pad_set_caps (demux->srcpad, demux->input_caps); */
GST_INFO_OBJECT (demux, "Input source caps: %" GST_PTR_FORMAT,
demux->input_caps);
demux->do_typefind = FALSE;
}
gst_caps_unref (caps);
} else {
gst_fragment_set_caps (download, demux->input_caps);
}
if (discont) {
GST_DEBUG_OBJECT (demux, "Marking fragment as discontinuous");
GST_BUFFER_FLAG_SET (buf, GST_BUFFER_FLAG_DISCONT);
}
GST_DEBUG_OBJECT (demux, "Pushing fragment in queue");
g_queue_push_tail (demux->queue, download);
if (!caching) {
GST_TASK_SIGNAL (demux->updates_task);
gst_task_start (demux->stream_task);
}
return TRUE;
error:
{
gst_hls_demux_stop (demux);
return FALSE;
}
}