gstreamer/gst/rtsp-server/rtsp-session-pool.c

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/* GStreamer
* Copyright (C) 2008 Wim Taymans <wim.taymans at gmail.com>
*
* 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
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* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
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*/
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/**
* SECTION:rtsp-session-pool
* @short_description: An object for managing sessions
* @see_also: #GstRTSPSession
*
* The #GstRTSPSessionPool object manages a list of #GstRTSPSession objects.
*
* The maximum number of sessions can be configured with
* gst_rtsp_session_pool_set_max_sessions(). The current number of sessions can
* be retrieved with gst_rtsp_session_pool_get_n_sessions().
*
* Use gst_rtsp_session_pool_create() to create a new #GstRTSPSession object.
* The session object can be found again with its id and
* gst_rtsp_session_pool_find().
*
* All sessions can be iterated with gst_rtsp_session_pool_filter().
*
* Run gst_rtsp_session_pool_cleanup() periodically to remove timed out sessions
* or use gst_rtsp_session_pool_create_watch() to be notified when session
* cleanup should be performed.
*
* Last reviewed on 2013-07-11 (1.0.0)
*/
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#include "rtsp-session-pool.h"
#define GST_RTSP_SESSION_POOL_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE ((obj), GST_TYPE_RTSP_SESSION_POOL, GstRTSPSessionPoolPrivate))
struct _GstRTSPSessionPoolPrivate
{
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GMutex lock; /* protects everything in this struct */
guint max_sessions;
GHashTable *sessions;
guint sessions_cookie;
};
#define DEFAULT_MAX_SESSIONS 0
enum
{
PROP_0,
PROP_MAX_SESSIONS,
PROP_LAST
};
static const gchar session_id_charset[] =
{ 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D',
'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S',
'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', '-', '_', '.', '+' /* '$' Live555 in VLC strips off $ chars */
};
enum
{
SIGNAL_SESSION_REMOVED,
SIGNAL_LAST
};
static guint gst_rtsp_session_pool_signals[SIGNAL_LAST] = { 0 };
GST_DEBUG_CATEGORY_STATIC (rtsp_session_debug);
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#define GST_CAT_DEFAULT rtsp_session_debug
static void gst_rtsp_session_pool_get_property (GObject * object, guint propid,
GValue * value, GParamSpec * pspec);
static void gst_rtsp_session_pool_set_property (GObject * object, guint propid,
const GValue * value, GParamSpec * pspec);
static void gst_rtsp_session_pool_finalize (GObject * object);
static gchar *create_session_id (GstRTSPSessionPool * pool);
static GstRTSPSession *create_session (GstRTSPSessionPool * pool,
const gchar * id);
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G_DEFINE_TYPE (GstRTSPSessionPool, gst_rtsp_session_pool, G_TYPE_OBJECT);
static void
gst_rtsp_session_pool_class_init (GstRTSPSessionPoolClass * klass)
{
GObjectClass *gobject_class;
g_type_class_add_private (klass, sizeof (GstRTSPSessionPoolPrivate));
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gobject_class = G_OBJECT_CLASS (klass);
gobject_class->get_property = gst_rtsp_session_pool_get_property;
gobject_class->set_property = gst_rtsp_session_pool_set_property;
gobject_class->finalize = gst_rtsp_session_pool_finalize;
g_object_class_install_property (gobject_class, PROP_MAX_SESSIONS,
g_param_spec_uint ("max-sessions", "Max Sessions",
"the maximum amount of sessions (0 = unlimited)",
0, G_MAXUINT, DEFAULT_MAX_SESSIONS,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_rtsp_session_pool_signals[SIGNAL_SESSION_REMOVED] =
g_signal_new ("session-removed", G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST, G_STRUCT_OFFSET (GstRTSPSessionPoolClass,
session_removed), NULL, NULL, g_cclosure_marshal_generic, G_TYPE_NONE,
1, GST_TYPE_RTSP_SESSION);
klass->create_session_id = create_session_id;
klass->create_session = create_session;
GST_DEBUG_CATEGORY_INIT (rtsp_session_debug, "rtspsessionpool", 0,
"GstRTSPSessionPool");
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}
static void
gst_rtsp_session_pool_init (GstRTSPSessionPool * pool)
{
GstRTSPSessionPoolPrivate *priv = GST_RTSP_SESSION_POOL_GET_PRIVATE (pool);
pool->priv = priv;
g_mutex_init (&priv->lock);
priv->sessions = g_hash_table_new_full (g_str_hash, g_str_equal,
NULL, g_object_unref);
priv->max_sessions = DEFAULT_MAX_SESSIONS;
}
static GstRTSPFilterResult
remove_sessions_func (GstRTSPSessionPool * pool, GstRTSPSession * session,
gpointer user_data)
{
return GST_RTSP_FILTER_REMOVE;
}
static void
gst_rtsp_session_pool_finalize (GObject * object)
{
GstRTSPSessionPool *pool = GST_RTSP_SESSION_POOL (object);
GstRTSPSessionPoolPrivate *priv = pool->priv;
gst_rtsp_session_pool_filter (pool, remove_sessions_func, NULL);
g_hash_table_unref (priv->sessions);
g_mutex_clear (&priv->lock);
G_OBJECT_CLASS (gst_rtsp_session_pool_parent_class)->finalize (object);
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}
static void
gst_rtsp_session_pool_get_property (GObject * object, guint propid,
GValue * value, GParamSpec * pspec)
{
GstRTSPSessionPool *pool = GST_RTSP_SESSION_POOL (object);
switch (propid) {
case PROP_MAX_SESSIONS:
g_value_set_uint (value, gst_rtsp_session_pool_get_max_sessions (pool));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, propid, pspec);
break;
}
}
static void
gst_rtsp_session_pool_set_property (GObject * object, guint propid,
const GValue * value, GParamSpec * pspec)
{
GstRTSPSessionPool *pool = GST_RTSP_SESSION_POOL (object);
switch (propid) {
case PROP_MAX_SESSIONS:
gst_rtsp_session_pool_set_max_sessions (pool, g_value_get_uint (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, propid, pspec);
break;
}
}
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/**
* gst_rtsp_session_pool_new:
*
* Create a new #GstRTSPSessionPool instance.
*
* Returns: (transfer full): A new #GstRTSPSessionPool. g_object_unref() after
* usage.
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*/
GstRTSPSessionPool *
gst_rtsp_session_pool_new (void)
{
GstRTSPSessionPool *result;
result = g_object_new (GST_TYPE_RTSP_SESSION_POOL, NULL);
return result;
}
/**
* gst_rtsp_session_pool_set_max_sessions:
* @pool: a #GstRTSPSessionPool
* @max: the maximum number of sessions
*
* Configure the maximum allowed number of sessions in @pool to @max.
* A value of 0 means an unlimited amount of sessions.
*/
void
gst_rtsp_session_pool_set_max_sessions (GstRTSPSessionPool * pool, guint max)
{
GstRTSPSessionPoolPrivate *priv;
g_return_if_fail (GST_IS_RTSP_SESSION_POOL (pool));
priv = pool->priv;
g_mutex_lock (&priv->lock);
priv->max_sessions = max;
g_mutex_unlock (&priv->lock);
}
/**
* gst_rtsp_session_pool_get_max_sessions:
* @pool: a #GstRTSPSessionPool
*
* Get the maximum allowed number of sessions in @pool. 0 means an unlimited
* amount of sessions.
*
* Returns: the maximum allowed number of sessions.
*/
guint
gst_rtsp_session_pool_get_max_sessions (GstRTSPSessionPool * pool)
{
GstRTSPSessionPoolPrivate *priv;
guint result;
g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), 0);
priv = pool->priv;
g_mutex_lock (&priv->lock);
result = priv->max_sessions;
g_mutex_unlock (&priv->lock);
return result;
}
/**
* gst_rtsp_session_pool_get_n_sessions:
* @pool: a #GstRTSPSessionPool
*
* Get the amount of active sessions in @pool.
*
* Returns: the amount of active sessions in @pool.
*/
guint
gst_rtsp_session_pool_get_n_sessions (GstRTSPSessionPool * pool)
{
GstRTSPSessionPoolPrivate *priv;
guint result;
g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), 0);
priv = pool->priv;
g_mutex_lock (&priv->lock);
result = g_hash_table_size (priv->sessions);
g_mutex_unlock (&priv->lock);
return result;
}
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/**
* gst_rtsp_session_pool_find:
* @pool: the pool to search
* @sessionid: the session id
*
* Find the session with @sessionid in @pool. The access time of the session
* will be updated with gst_rtsp_session_touch().
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*
* Returns: (transfer full) (nullable): the #GstRTSPSession with @sessionid
* or %NULL when the session did not exist. g_object_unref() after usage.
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*/
GstRTSPSession *
gst_rtsp_session_pool_find (GstRTSPSessionPool * pool, const gchar * sessionid)
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{
GstRTSPSessionPoolPrivate *priv;
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GstRTSPSession *result;
g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), NULL);
g_return_val_if_fail (sessionid != NULL, NULL);
priv = pool->priv;
g_mutex_lock (&priv->lock);
result = g_hash_table_lookup (priv->sessions, sessionid);
if (result) {
g_object_ref (result);
gst_rtsp_session_touch (result);
}
g_mutex_unlock (&priv->lock);
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return result;
}
static gchar *
create_session_id (GstRTSPSessionPool * pool)
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{
gchar id[16];
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gint i;
for (i = 0; i < 16; i++) {
id[i] =
session_id_charset[g_random_int_range (0,
G_N_ELEMENTS (session_id_charset))];
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}
return g_strndup (id, 16);
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}
static GstRTSPSession *
create_session (GstRTSPSessionPool * pool, const gchar * id)
{
return gst_rtsp_session_new (id);
}
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/**
* gst_rtsp_session_pool_create:
* @pool: a #GstRTSPSessionPool
*
* Create a new #GstRTSPSession object in @pool.
*
* Returns: (transfer full) (nullable): a new #GstRTSPSession.
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*/
GstRTSPSession *
gst_rtsp_session_pool_create (GstRTSPSessionPool * pool)
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{
GstRTSPSessionPoolPrivate *priv;
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GstRTSPSession *result = NULL;
GstRTSPSessionPoolClass *klass;
gchar *id = NULL;
guint retry;
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g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), NULL);
priv = pool->priv;
klass = GST_RTSP_SESSION_POOL_GET_CLASS (pool);
retry = 0;
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do {
/* start by creating a new random session id, we assume that this is random
* enough to not cause a collision, which we will check later */
if (klass->create_session_id)
id = klass->create_session_id (pool);
else
goto no_function;
if (id == NULL)
goto no_session;
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g_mutex_lock (&priv->lock);
/* check session limit */
if (priv->max_sessions > 0) {
if (g_hash_table_size (priv->sessions) >= priv->max_sessions)
goto too_many_sessions;
}
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/* check if the sessionid existed */
result = g_hash_table_lookup (priv->sessions, id);
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if (result) {
/* found, retry with a different session id */
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result = NULL;
retry++;
if (retry > 100)
goto collision;
} else {
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/* not found, create session and insert it in the pool */
if (klass->create_session)
result = create_session (pool, id);
if (result == NULL)
goto too_many_sessions;
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/* take additional ref for the pool */
g_object_ref (result);
g_hash_table_insert (priv->sessions,
(gchar *) gst_rtsp_session_get_sessionid (result), result);
priv->sessions_cookie++;
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}
g_mutex_unlock (&priv->lock);
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g_free (id);
} while (result == NULL);
return result;
/* ERRORS */
no_function:
{
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GST_WARNING ("no create_session_id vmethod in GstRTSPSessionPool %p", pool);
return NULL;
}
no_session:
{
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GST_WARNING ("can't create session id with GstRTSPSessionPool %p", pool);
return NULL;
}
collision:
{
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GST_WARNING ("can't find unique sessionid for GstRTSPSessionPool %p", pool);
g_mutex_unlock (&priv->lock);
g_free (id);
return NULL;
}
too_many_sessions:
{
GST_WARNING ("session pool reached max sessions of %d", priv->max_sessions);
g_mutex_unlock (&priv->lock);
g_free (id);
return NULL;
}
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}
/**
* gst_rtsp_session_pool_remove:
* @pool: a #GstRTSPSessionPool
* @sess: (transfer none): a #GstRTSPSession
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*
* Remove @sess from @pool, releasing the ref that the pool has on @sess.
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*
* Returns: %TRUE if the session was found and removed.
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*/
gboolean
gst_rtsp_session_pool_remove (GstRTSPSessionPool * pool, GstRTSPSession * sess)
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{
GstRTSPSessionPoolPrivate *priv;
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gboolean found;
g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), FALSE);
g_return_val_if_fail (GST_IS_RTSP_SESSION (sess), FALSE);
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priv = pool->priv;
g_mutex_lock (&priv->lock);
g_object_ref (sess);
found =
g_hash_table_remove (priv->sessions,
gst_rtsp_session_get_sessionid (sess));
if (found)
priv->sessions_cookie++;
g_mutex_unlock (&priv->lock);
if (found)
g_signal_emit (pool, gst_rtsp_session_pool_signals[SIGNAL_SESSION_REMOVED],
0, sess);
g_object_unref (sess);
return found;
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}
typedef struct
{
gint64 now_monotonic_time;
GstRTSPSessionPool *pool;
GList *removed;
} CleanupData;
static gboolean
cleanup_func (gchar * sessionid, GstRTSPSession * sess, CleanupData * data)
{
gboolean expired;
expired = gst_rtsp_session_is_expired_usec (sess, data->now_monotonic_time);
if (expired) {
GST_DEBUG ("session expired");
data->removed = g_list_prepend (data->removed, g_object_ref (sess));
}
return expired;
}
/**
* gst_rtsp_session_pool_cleanup:
* @pool: a #GstRTSPSessionPool
*
* Inspect all the sessions in @pool and remove the sessions that are inactive
* for more than their timeout.
*
* Returns: the amount of sessions that got removed.
*/
guint
gst_rtsp_session_pool_cleanup (GstRTSPSessionPool * pool)
{
GstRTSPSessionPoolPrivate *priv;
guint result;
CleanupData data;
GList *walk;
g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), 0);
priv = pool->priv;
data.now_monotonic_time = g_get_monotonic_time ();
data.pool = pool;
data.removed = NULL;
g_mutex_lock (&priv->lock);
result =
g_hash_table_foreach_remove (priv->sessions, (GHRFunc) cleanup_func,
&data);
if (result > 0)
priv->sessions_cookie++;
g_mutex_unlock (&priv->lock);
for (walk = data.removed; walk; walk = walk->next) {
GstRTSPSession *sess = walk->data;
g_signal_emit (pool,
gst_rtsp_session_pool_signals[SIGNAL_SESSION_REMOVED], 0, sess);
g_object_unref (sess);
}
g_list_free (data.removed);
return result;
}
/**
* gst_rtsp_session_pool_filter:
* @pool: a #GstRTSPSessionPool
* @func: (scope call) (allow-none): a callback
* @user_data: (closure): user data passed to @func
*
* Call @func for each session in @pool. The result value of @func determines
* what happens to the session. @func will be called with the session pool
* locked so no further actions on @pool can be performed from @func.
*
* If @func returns #GST_RTSP_FILTER_REMOVE, the session will be set to the
* expired state with gst_rtsp_session_set_expired() and removed from
* @pool.
*
* If @func returns #GST_RTSP_FILTER_KEEP, the session will remain in @pool.
*
* If @func returns #GST_RTSP_FILTER_REF, the session will remain in @pool but
* will also be added with an additional ref to the result GList of this
* function..
*
* When @func is %NULL, #GST_RTSP_FILTER_REF will be assumed for all sessions.
*
* Returns: (element-type GstRTSPSession) (transfer full): a GList with all
* sessions for which @func returned #GST_RTSP_FILTER_REF. After usage, each
* element in the GList should be unreffed before the list is freed.
*/
GList *
gst_rtsp_session_pool_filter (GstRTSPSessionPool * pool,
GstRTSPSessionPoolFilterFunc func, gpointer user_data)
{
GstRTSPSessionPoolPrivate *priv;
GHashTableIter iter;
gpointer key, value;
GList *result;
GHashTable *visited;
guint cookie;
g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), NULL);
priv = pool->priv;
result = NULL;
if (func)
visited = g_hash_table_new_full (NULL, NULL, g_object_unref, NULL);
g_mutex_lock (&priv->lock);
restart:
g_hash_table_iter_init (&iter, priv->sessions);
cookie = priv->sessions_cookie;
while (g_hash_table_iter_next (&iter, &key, &value)) {
GstRTSPSession *session = value;
GstRTSPFilterResult res;
gboolean changed;
if (func) {
/* only visit each session once */
if (g_hash_table_contains (visited, session))
continue;
g_hash_table_add (visited, g_object_ref (session));
g_mutex_unlock (&priv->lock);
res = func (pool, session, user_data);
g_mutex_lock (&priv->lock);
} else
res = GST_RTSP_FILTER_REF;
changed = (cookie != priv->sessions_cookie);
switch (res) {
case GST_RTSP_FILTER_REMOVE:
{
gboolean removed = TRUE;
if (changed)
/* something changed, check if we still have the session */
removed = g_hash_table_remove (priv->sessions, key);
else
g_hash_table_iter_remove (&iter);
if (removed) {
/* if we managed to remove the session, update the cookie and
* signal */
cookie = ++priv->sessions_cookie;
g_mutex_unlock (&priv->lock);
g_signal_emit (pool,
gst_rtsp_session_pool_signals[SIGNAL_SESSION_REMOVED], 0,
session);
g_mutex_lock (&priv->lock);
/* cookie could have changed again, make sure we restart */
changed |= (cookie != priv->sessions_cookie);
}
break;
}
case GST_RTSP_FILTER_REF:
/* keep ref */
result = g_list_prepend (result, g_object_ref (session));
break;
case GST_RTSP_FILTER_KEEP:
default:
break;
}
if (changed)
goto restart;
}
g_mutex_unlock (&priv->lock);
if (func)
g_hash_table_unref (visited);
return result;
}
typedef struct
{
GSource source;
GstRTSPSessionPool *pool;
gint timeout;
} GstPoolSource;
static void
collect_timeout (gchar * sessionid, GstRTSPSession * sess, GstPoolSource * psrc)
{
gint timeout;
gint64 now_monotonic_time;
now_monotonic_time = g_get_monotonic_time ();
timeout = gst_rtsp_session_next_timeout_usec (sess, now_monotonic_time);
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GST_INFO ("%p: next timeout: %d", sess, timeout);
if (psrc->timeout == -1 || timeout < psrc->timeout)
psrc->timeout = timeout;
}
static gboolean
gst_pool_source_prepare (GSource * source, gint * timeout)
{
GstRTSPSessionPoolPrivate *priv;
GstPoolSource *psrc;
gboolean result;
psrc = (GstPoolSource *) source;
psrc->timeout = -1;
priv = psrc->pool->priv;
g_mutex_lock (&priv->lock);
g_hash_table_foreach (priv->sessions, (GHFunc) collect_timeout, psrc);
g_mutex_unlock (&priv->lock);
if (timeout)
*timeout = psrc->timeout;
result = psrc->timeout == 0;
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GST_INFO ("prepare %d, %d", psrc->timeout, result);
return result;
}
static gboolean
gst_pool_source_check (GSource * source)
{
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GST_INFO ("check");
return gst_pool_source_prepare (source, NULL);
}
static gboolean
gst_pool_source_dispatch (GSource * source, GSourceFunc callback,
gpointer user_data)
{
gboolean res;
GstPoolSource *psrc = (GstPoolSource *) source;
GstRTSPSessionPoolFunc func = (GstRTSPSessionPoolFunc) callback;
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GST_INFO ("dispatch");
if (func)
res = func (psrc->pool, user_data);
else
res = FALSE;
return res;
}
static void
gst_pool_source_finalize (GSource * source)
{
GstPoolSource *psrc = (GstPoolSource *) source;
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GST_INFO ("finalize %p", psrc);
g_object_unref (psrc->pool);
psrc->pool = NULL;
}
static GSourceFuncs gst_pool_source_funcs = {
gst_pool_source_prepare,
gst_pool_source_check,
gst_pool_source_dispatch,
gst_pool_source_finalize
};
/**
* gst_rtsp_session_pool_create_watch:
* @pool: a #GstRTSPSessionPool
*
* Create a #GSource that will be dispatched when the session should be cleaned
* up.
*
* Returns: (transfer full): a #GSource
*/
GSource *
gst_rtsp_session_pool_create_watch (GstRTSPSessionPool * pool)
{
GstPoolSource *source;
g_return_val_if_fail (GST_IS_RTSP_SESSION_POOL (pool), NULL);
source = (GstPoolSource *) g_source_new (&gst_pool_source_funcs,
sizeof (GstPoolSource));
source->pool = g_object_ref (pool);
return (GSource *) source;
}