gstreamer/gst/rtsp-server/rtsp-mount-points.c
Xavier Claessens f7bbd9dd86 GstRTSPMountPoints: Remove any existing factory before adding a new one
The documentation of gst_rtsp_mount_points_add_factory() says "Any
previous mount point will be freed" which was true when it was
implemented using a GHashTable. But in 2012 it got rewrote using a
GSequence and since then it could have 2 factories for the same path.
Which one gets used is random, depending on the sorting order of 2
identical items.
2019-11-04 12:01:09 +00:00

386 lines
10 KiB
C

/* 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
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
/**
* SECTION:rtsp-mount-points
* @short_description: Map a path to media
* @see_also: #GstRTSPMediaFactory, #GstRTSPClient
*
* A #GstRTSPMountPoints object maintains a relation between paths
* and #GstRTSPMediaFactory objects. This object is usually given to
* #GstRTSPClient and used to find the media attached to a path.
*
* With gst_rtsp_mount_points_add_factory () and
* gst_rtsp_mount_points_remove_factory(), factories can be added and
* removed.
*
* With gst_rtsp_mount_points_match() you can find the #GstRTSPMediaFactory
* object that completely matches the given path.
*
* Last reviewed on 2013-07-11 (1.0.0)
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "rtsp-mount-points.h"
typedef struct
{
gchar *path;
gint len;
GstRTSPMediaFactory *factory;
} DataItem;
static DataItem *
data_item_new (gchar * path, gint len, GstRTSPMediaFactory * factory)
{
DataItem *item;
item = g_slice_alloc (sizeof (DataItem));
item->path = path;
item->len = len;
item->factory = factory;
return item;
}
static void
data_item_free (gpointer data)
{
DataItem *item = data;
g_free (item->path);
g_object_unref (item->factory);
g_slice_free1 (sizeof (DataItem), item);
}
static void
data_item_dump (gconstpointer a, gconstpointer prefix)
{
const DataItem *item = a;
GST_DEBUG ("%s%s %p", (gchar *) prefix, item->path, item->factory);
}
static gint
data_item_compare (gconstpointer a, gconstpointer b, gpointer user_data)
{
const DataItem *item1 = a, *item2 = b;
gint res;
res = g_strcmp0 (item1->path, item2->path);
return res;
}
struct _GstRTSPMountPointsPrivate
{
GMutex lock;
GSequence *mounts; /* protected by lock */
gboolean dirty;
};
G_DEFINE_TYPE_WITH_PRIVATE (GstRTSPMountPoints, gst_rtsp_mount_points,
G_TYPE_OBJECT);
GST_DEBUG_CATEGORY_STATIC (rtsp_media_debug);
#define GST_CAT_DEFAULT rtsp_media_debug
static gchar *default_make_path (GstRTSPMountPoints * mounts,
const GstRTSPUrl * url);
static void gst_rtsp_mount_points_finalize (GObject * obj);
static void
gst_rtsp_mount_points_class_init (GstRTSPMountPointsClass * klass)
{
GObjectClass *gobject_class;
gobject_class = G_OBJECT_CLASS (klass);
gobject_class->finalize = gst_rtsp_mount_points_finalize;
klass->make_path = default_make_path;
GST_DEBUG_CATEGORY_INIT (rtsp_media_debug, "rtspmountpoints", 0,
"GstRTSPMountPoints");
}
static void
gst_rtsp_mount_points_init (GstRTSPMountPoints * mounts)
{
GstRTSPMountPointsPrivate *priv;
GST_DEBUG_OBJECT (mounts, "created");
mounts->priv = priv = gst_rtsp_mount_points_get_instance_private (mounts);
g_mutex_init (&priv->lock);
priv->mounts = g_sequence_new (data_item_free);
priv->dirty = FALSE;
}
static void
gst_rtsp_mount_points_finalize (GObject * obj)
{
GstRTSPMountPoints *mounts = GST_RTSP_MOUNT_POINTS (obj);
GstRTSPMountPointsPrivate *priv = mounts->priv;
GST_DEBUG_OBJECT (mounts, "finalized");
g_sequence_free (priv->mounts);
g_mutex_clear (&priv->lock);
G_OBJECT_CLASS (gst_rtsp_mount_points_parent_class)->finalize (obj);
}
/**
* gst_rtsp_mount_points_new:
*
* Make a new mount points object.
*
* Returns: (transfer full): a new #GstRTSPMountPoints
*/
GstRTSPMountPoints *
gst_rtsp_mount_points_new (void)
{
GstRTSPMountPoints *result;
result = g_object_new (GST_TYPE_RTSP_MOUNT_POINTS, NULL);
return result;
}
static gchar *
default_make_path (GstRTSPMountPoints * mounts, const GstRTSPUrl * url)
{
return g_strdup (url->abspath);
}
/**
* gst_rtsp_mount_points_make_path:
* @mounts: a #GstRTSPMountPoints
* @url: a #GstRTSPUrl
*
* Make a path string from @url.
*
* Returns: (transfer full) (nullable): a path string for @url, g_free() after usage.
*/
gchar *
gst_rtsp_mount_points_make_path (GstRTSPMountPoints * mounts,
const GstRTSPUrl * url)
{
GstRTSPMountPointsClass *klass;
gchar *result;
g_return_val_if_fail (GST_IS_RTSP_MOUNT_POINTS (mounts), NULL);
g_return_val_if_fail (url != NULL, NULL);
klass = GST_RTSP_MOUNT_POINTS_GET_CLASS (mounts);
if (klass->make_path)
result = klass->make_path (mounts, url);
else
result = NULL;
return result;
}
static gboolean
has_prefix (DataItem * str, DataItem * prefix)
{
/* prefix needs to be smaller than str */
if (str->len < prefix->len)
return FALSE;
/* if str is larger, it there should be a / following the prefix */
if (str->len > prefix->len && str->path[prefix->len] != '/')
return FALSE;
return strncmp (str->path, prefix->path, prefix->len) == 0;
}
/**
* gst_rtsp_mount_points_match:
* @mounts: a #GstRTSPMountPoints
* @path: a mount point
* @matched: (out) (allow-none): the amount of @path matched
*
* Find the factory in @mounts that has the longest match with @path.
*
* If @matched is %NULL, @path will match the factory exactly otherwise
* the amount of characters that matched is returned in @matched.
*
* Returns: (transfer full): the #GstRTSPMediaFactory for @path.
* g_object_unref() after usage.
*/
GstRTSPMediaFactory *
gst_rtsp_mount_points_match (GstRTSPMountPoints * mounts,
const gchar * path, gint * matched)
{
GstRTSPMountPointsPrivate *priv;
GstRTSPMediaFactory *result = NULL;
GSequenceIter *iter, *best;
DataItem item, *ritem;
g_return_val_if_fail (GST_IS_RTSP_MOUNT_POINTS (mounts), NULL);
g_return_val_if_fail (path != NULL, NULL);
priv = mounts->priv;
item.path = (gchar *) path;
item.len = strlen (path);
GST_LOG ("Looking for mount point path %s", path);
g_mutex_lock (&priv->lock);
if (priv->dirty) {
g_sequence_sort (priv->mounts, data_item_compare, mounts);
g_sequence_foreach (priv->mounts, (GFunc) data_item_dump,
(gpointer) "sort :");
priv->dirty = FALSE;
}
/* find the location of the media in the hashtable we only use the absolute
* path of the uri to find a media factory. If the factory depends on other
* properties found in the url, this method should be overridden. */
iter = g_sequence_get_begin_iter (priv->mounts);
best = NULL;
while (!g_sequence_iter_is_end (iter)) {
ritem = g_sequence_get (iter);
data_item_dump (ritem, "inspect: ");
/* The sequence is sorted, so any prefix match is an improvement upon
* the previous best match, as '/abc' will always be before '/abcd' */
if (has_prefix (&item, ritem)) {
if (best == NULL) {
data_item_dump (ritem, "prefix: ");
} else {
data_item_dump (ritem, "new best: ");
}
best = iter;
} else {
/* if have a match and the current item doesn't prefix match the best we
* found so far then we're moving away and can bail out of the loop */
if (best != NULL && !has_prefix (ritem, g_sequence_get (best)))
break;
}
iter = g_sequence_iter_next (iter);
}
if (best) {
ritem = g_sequence_get (best);
data_item_dump (ritem, "result: ");
if (matched || ritem->len == item.len) {
result = g_object_ref (ritem->factory);
if (matched)
*matched = ritem->len;
}
}
g_mutex_unlock (&priv->lock);
GST_INFO ("found media factory %p for path %s", result, path);
return result;
}
static void
gst_rtsp_mount_points_remove_factory_unlocked (GstRTSPMountPoints * mounts,
const gchar * path)
{
GstRTSPMountPointsPrivate *priv = mounts->priv;
DataItem item;
GSequenceIter *iter;
item.path = (gchar *) path;
if (priv->dirty) {
g_sequence_sort (priv->mounts, data_item_compare, mounts);
priv->dirty = FALSE;
}
iter = g_sequence_lookup (priv->mounts, &item, data_item_compare, mounts);
if (iter) {
g_sequence_remove (iter);
priv->dirty = TRUE;
}
}
/**
* gst_rtsp_mount_points_add_factory:
* @mounts: a #GstRTSPMountPoints
* @path: a mount point
* @factory: (transfer full): a #GstRTSPMediaFactory
*
* Attach @factory to the mount point @path in @mounts.
*
* @path is of the form (/node)+. Any previous mount point will be freed.
*
* Ownership is taken of the reference on @factory so that @factory should not be
* used after calling this function.
*/
void
gst_rtsp_mount_points_add_factory (GstRTSPMountPoints * mounts,
const gchar * path, GstRTSPMediaFactory * factory)
{
GstRTSPMountPointsPrivate *priv;
DataItem *item;
g_return_if_fail (GST_IS_RTSP_MOUNT_POINTS (mounts));
g_return_if_fail (GST_IS_RTSP_MEDIA_FACTORY (factory));
g_return_if_fail (path != NULL);
priv = mounts->priv;
item = data_item_new (g_strdup (path), strlen (path), factory);
GST_INFO ("adding media factory %p for path %s", factory, path);
g_mutex_lock (&priv->lock);
gst_rtsp_mount_points_remove_factory_unlocked (mounts, path);
g_sequence_append (priv->mounts, item);
priv->dirty = TRUE;
g_mutex_unlock (&priv->lock);
}
/**
* gst_rtsp_mount_points_remove_factory:
* @mounts: a #GstRTSPMountPoints
* @path: a mount point
*
* Remove the #GstRTSPMediaFactory associated with @path in @mounts.
*/
void
gst_rtsp_mount_points_remove_factory (GstRTSPMountPoints * mounts,
const gchar * path)
{
GstRTSPMountPointsPrivate *priv;
g_return_if_fail (GST_IS_RTSP_MOUNT_POINTS (mounts));
g_return_if_fail (path != NULL);
priv = mounts->priv;
GST_INFO ("removing media factory for path %s", path);
g_mutex_lock (&priv->lock);
gst_rtsp_mount_points_remove_factory_unlocked (mounts, path);
g_mutex_unlock (&priv->lock);
}