| /* GStreamer |
| * Copyright (C) 2012 Olivier Crete <olivier.crete@collabora.com> |
| * |
| * gstdevicemonitor.c: Device probing and monitoring |
| * |
| * 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., 59 Temple Place - Suite 330, |
| * Boston, MA 02111-1307, USA. |
| */ |
| |
| /** |
| * SECTION:gstdevicemonitor |
| * @short_description: A device monitor and prober |
| * @see_also: #GstDevice, #GstGlobalDeviceMonitor |
| * |
| * A #GstDeviceMonitor subclass is provided by a plugin that handles devices |
| * if there is a way to programatically list connected devices. It can also |
| * optionally provide updates to the list of connected devices. |
| * |
| * Each #GstDeviceMonitor subclass is a singleton, a plugin should |
| * normally provide a single subclass for all devices. |
| * |
| * Applications would normally use a #GstGlobalDeviceMonitor to monitor devices |
| * from all revelant monitors. |
| * |
| * Since: 1.4 |
| */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include "config.h" |
| #endif |
| |
| #include "gst_private.h" |
| |
| #include "gstdevicemonitor.h" |
| |
| #include "gstelementmetadata.h" |
| #include "gstquark.h" |
| |
| struct _GstDeviceMonitorPrivate |
| { |
| GstBus *bus; |
| |
| GMutex start_lock; |
| |
| gboolean started_count; |
| }; |
| |
| /* this is used in gstelementfactory.c:gst_element_register() */ |
| GQuark __gst_devicemonitorclass_factory = 0; |
| |
| static void gst_device_monitor_class_init (GstDeviceMonitorClass * klass); |
| static void gst_device_monitor_init (GstDeviceMonitor * element); |
| static void gst_device_monitor_base_class_init (gpointer g_class); |
| static void gst_device_monitor_base_class_finalize (gpointer g_class); |
| static void gst_device_monitor_dispose (GObject * object); |
| static void gst_device_monitor_finalize (GObject * object); |
| |
| static gpointer gst_device_monitor_parent_class = NULL; |
| |
| GType |
| gst_device_monitor_get_type (void) |
| { |
| static volatile gsize gst_device_monitor_type = 0; |
| |
| if (g_once_init_enter (&gst_device_monitor_type)) { |
| GType _type; |
| static const GTypeInfo element_info = { |
| sizeof (GstDeviceMonitorClass), |
| gst_device_monitor_base_class_init, |
| gst_device_monitor_base_class_finalize, |
| (GClassInitFunc) gst_device_monitor_class_init, |
| NULL, |
| NULL, |
| sizeof (GstDeviceMonitor), |
| 0, |
| (GInstanceInitFunc) gst_device_monitor_init, |
| NULL |
| }; |
| |
| _type = g_type_register_static (GST_TYPE_OBJECT, "GstDeviceMonitor", |
| &element_info, G_TYPE_FLAG_ABSTRACT); |
| |
| __gst_devicemonitorclass_factory = |
| g_quark_from_static_string ("GST_DEVICEMONITORCLASS_FACTORY"); |
| g_once_init_leave (&gst_device_monitor_type, _type); |
| } |
| return gst_device_monitor_type; |
| } |
| |
| static void |
| gst_device_monitor_base_class_init (gpointer g_class) |
| { |
| GstDeviceMonitorClass *klass = GST_DEVICE_MONITOR_CLASS (g_class); |
| |
| /* Copy the element details here so elements can inherit the |
| * details from their base class and classes only need to set |
| * the details in class_init instead of base_init */ |
| klass->metadata = |
| klass->metadata ? gst_structure_copy (klass->metadata) : |
| gst_structure_new_empty ("metadata"); |
| |
| klass->factory = g_type_get_qdata (G_TYPE_FROM_CLASS (klass), |
| __gst_devicemonitorclass_factory); |
| } |
| |
| static void |
| gst_device_monitor_base_class_finalize (gpointer g_class) |
| { |
| GstDeviceMonitorClass *klass = GST_DEVICE_MONITOR_CLASS (g_class); |
| |
| gst_structure_free (klass->metadata); |
| } |
| |
| static void |
| gst_device_monitor_class_init (GstDeviceMonitorClass * klass) |
| { |
| GObjectClass *gobject_class = (GObjectClass *) klass; |
| |
| gst_device_monitor_parent_class = g_type_class_peek_parent (klass); |
| |
| g_type_class_add_private (klass, sizeof (GstDeviceMonitorPrivate)); |
| |
| gobject_class->dispose = gst_device_monitor_dispose; |
| gobject_class->finalize = gst_device_monitor_finalize; |
| } |
| |
| static void |
| gst_device_monitor_init (GstDeviceMonitor * monitor) |
| { |
| monitor->priv = G_TYPE_INSTANCE_GET_PRIVATE (monitor, |
| GST_TYPE_DEVICE_MONITOR, GstDeviceMonitorPrivate); |
| |
| g_mutex_init (&monitor->priv->start_lock); |
| |
| monitor->priv->bus = gst_bus_new (); |
| gst_bus_set_flushing (monitor->priv->bus, TRUE); |
| } |
| |
| |
| static void |
| gst_device_monitor_dispose (GObject * object) |
| { |
| GstDeviceMonitor *monitor = GST_DEVICE_MONITOR (object); |
| |
| gst_object_replace ((GstObject **) & monitor->priv->bus, NULL); |
| |
| GST_OBJECT_LOCK (monitor); |
| g_list_free_full (monitor->devices, (GDestroyNotify) gst_object_unparent); |
| monitor->devices = NULL; |
| GST_OBJECT_UNLOCK (monitor); |
| |
| G_OBJECT_CLASS (gst_device_monitor_parent_class)->dispose (object); |
| } |
| |
| static void |
| gst_device_monitor_finalize (GObject * object) |
| { |
| GstDeviceMonitor *monitor = GST_DEVICE_MONITOR (object); |
| |
| g_mutex_clear (&monitor->priv->start_lock); |
| |
| G_OBJECT_CLASS (gst_device_monitor_parent_class)->finalize (object); |
| } |
| |
| /** |
| * gst_device_monitor_class_add_metadata: |
| * @klass: class to set metadata for |
| * @key: the key to set |
| * @value: the value to set |
| * |
| * Set @key with @value as metadata in @klass. |
| */ |
| void |
| gst_device_monitor_class_add_metadata (GstDeviceMonitorClass * klass, |
| const gchar * key, const gchar * value) |
| { |
| g_return_if_fail (GST_IS_DEVICE_MONITOR_CLASS (klass)); |
| g_return_if_fail (key != NULL); |
| g_return_if_fail (value != NULL); |
| |
| gst_structure_set ((GstStructure *) klass->metadata, |
| key, G_TYPE_STRING, value, NULL); |
| } |
| |
| /** |
| * gst_device_monitor_class_add_static_metadata: |
| * @klass: class to set metadata for |
| * @key: the key to set |
| * @value: the value to set |
| * |
| * Set @key with @value as metadata in @klass. |
| * |
| * Same as gst_device_monitor_class_add_metadata(), but @value must be a static string |
| * or an inlined string, as it will not be copied. (GStreamer plugins will |
| * be made resident once loaded, so this function can be used even from |
| * dynamically loaded plugins.) |
| * |
| * Since: 1.4 |
| */ |
| void |
| gst_device_monitor_class_add_static_metadata (GstDeviceMonitorClass * klass, |
| const gchar * key, const gchar * value) |
| { |
| GValue val = G_VALUE_INIT; |
| |
| g_return_if_fail (GST_IS_DEVICE_MONITOR_CLASS (klass)); |
| g_return_if_fail (key != NULL); |
| g_return_if_fail (value != NULL); |
| |
| g_value_init (&val, G_TYPE_STRING); |
| g_value_set_static_string (&val, value); |
| gst_structure_take_value ((GstStructure *) klass->metadata, key, &val); |
| } |
| |
| /** |
| * gst_device_monitor_class_set_metadata: |
| * @klass: class to set metadata for |
| * @longname: The long English name of the device monitor. E.g. "File Sink" |
| * @classification: String describing the type of device monitor, as an unordered list |
| * separated with slashes ('/'). See draft-klass.txt of the design docs |
| * for more details and common types. E.g: "Sink/File" |
| * @description: Sentence describing the purpose of the device monitor. |
| * E.g: "Write stream to a file" |
| * @author: Name and contact details of the author(s). Use \n to separate |
| * multiple author metadata. E.g: "Joe Bloggs <joe.blogs at foo.com>" |
| * |
| * Sets the detailed information for a #GstDeviceMonitorClass. |
| * <note>This function is for use in _class_init functions only.</note> |
| * |
| * Since: 1.4 |
| */ |
| void |
| gst_device_monitor_class_set_metadata (GstDeviceMonitorClass * klass, |
| const gchar * longname, const gchar * classification, |
| const gchar * description, const gchar * author) |
| { |
| g_return_if_fail (GST_IS_DEVICE_MONITOR_CLASS (klass)); |
| g_return_if_fail (longname != NULL && *longname != '\0'); |
| g_return_if_fail (classification != NULL && *classification != '\0'); |
| g_return_if_fail (description != NULL && *description != '\0'); |
| g_return_if_fail (author != NULL && *author != '\0'); |
| |
| gst_structure_id_set ((GstStructure *) klass->metadata, |
| GST_QUARK (ELEMENT_METADATA_LONGNAME), G_TYPE_STRING, longname, |
| GST_QUARK (ELEMENT_METADATA_KLASS), G_TYPE_STRING, classification, |
| GST_QUARK (ELEMENT_METADATA_DESCRIPTION), G_TYPE_STRING, description, |
| GST_QUARK (ELEMENT_METADATA_AUTHOR), G_TYPE_STRING, author, NULL); |
| } |
| |
| /** |
| * gst_device_monitor_class_set_static_metadata: |
| * @klass: class to set metadata for |
| * @longname: The long English name of the element. E.g. "File Sink" |
| * @classification: String describing the type of element, as an unordered list |
| * separated with slashes ('/'). See draft-klass.txt of the design docs |
| * for more details and common types. E.g: "Sink/File" |
| * @description: Sentence describing the purpose of the element. |
| * E.g: "Write stream to a file" |
| * @author: Name and contact details of the author(s). Use \n to separate |
| * multiple author metadata. E.g: "Joe Bloggs <joe.blogs at foo.com>" |
| * |
| * Sets the detailed information for a #GstDeviceMonitorClass. |
| * <note>This function is for use in _class_init functions only.</note> |
| * |
| * Same as gst_device_monitor_class_set_metadata(), but @longname, @classification, |
| * @description, and @author must be static strings or inlined strings, as |
| * they will not be copied. (GStreamer plugins will be made resident once |
| * loaded, so this function can be used even from dynamically loaded plugins.) |
| * |
| * Since: 1.4 |
| */ |
| void |
| gst_device_monitor_class_set_static_metadata (GstDeviceMonitorClass * klass, |
| const gchar * longname, const gchar * classification, |
| const gchar * description, const gchar * author) |
| { |
| GstStructure *s = (GstStructure *) klass->metadata; |
| GValue val = G_VALUE_INIT; |
| |
| g_return_if_fail (GST_IS_DEVICE_MONITOR_CLASS (klass)); |
| g_return_if_fail (longname != NULL && *longname != '\0'); |
| g_return_if_fail (classification != NULL && *classification != '\0'); |
| g_return_if_fail (description != NULL && *description != '\0'); |
| g_return_if_fail (author != NULL && *author != '\0'); |
| |
| g_value_init (&val, G_TYPE_STRING); |
| |
| g_value_set_static_string (&val, longname); |
| gst_structure_id_set_value (s, GST_QUARK (ELEMENT_METADATA_LONGNAME), &val); |
| |
| g_value_set_static_string (&val, classification); |
| gst_structure_id_set_value (s, GST_QUARK (ELEMENT_METADATA_KLASS), &val); |
| |
| g_value_set_static_string (&val, description); |
| gst_structure_id_set_value (s, GST_QUARK (ELEMENT_METADATA_DESCRIPTION), |
| &val); |
| |
| g_value_set_static_string (&val, author); |
| gst_structure_id_take_value (s, GST_QUARK (ELEMENT_METADATA_AUTHOR), &val); |
| } |
| |
| /** |
| * gst_device_monitor_class_get_metadata: |
| * @klass: class to get metadata for |
| * @key: the key to get |
| * |
| * Get metadata with @key in @klass. |
| * |
| * Returns: the metadata for @key. |
| * |
| * Since: 1.4 |
| */ |
| const gchar * |
| gst_device_monitor_class_get_metadata (GstDeviceMonitorClass * klass, |
| const gchar * key) |
| { |
| g_return_val_if_fail (GST_IS_DEVICE_MONITOR_CLASS (klass), NULL); |
| g_return_val_if_fail (key != NULL, NULL); |
| |
| return gst_structure_get_string ((GstStructure *) klass->metadata, key); |
| } |
| |
| /** |
| * gst_device_monitor_get_devices: |
| * @monitor: A #GstDeviceMonitor |
| * |
| * Gets a list of devices that this monitor understands. This may actually |
| * probe the hardware if the monitor is not currently started. |
| * |
| * Returns: (transfer full) (element-type GstDevice): a #GList of |
| * #GstDevice |
| * |
| * Since: 1.4 |
| */ |
| |
| GList * |
| gst_device_monitor_get_devices (GstDeviceMonitor * monitor) |
| { |
| GstDeviceMonitorClass *klass; |
| GList *devices = NULL; |
| gboolean started; |
| GList *item; |
| |
| g_return_val_if_fail (GST_IS_DEVICE_MONITOR (monitor), NULL); |
| klass = GST_DEVICE_MONITOR_GET_CLASS (monitor); |
| |
| g_mutex_lock (&monitor->priv->start_lock); |
| started = (monitor->priv->started_count > 0); |
| |
| if (started) { |
| GST_OBJECT_LOCK (monitor); |
| for (item = monitor->devices; item; item = item->next) |
| devices = g_list_prepend (devices, gst_object_ref (item->data)); |
| GST_OBJECT_UNLOCK (monitor); |
| } else if (klass->probe) |
| devices = klass->probe (monitor); |
| |
| g_mutex_unlock (&monitor->priv->start_lock); |
| |
| return devices; |
| } |
| |
| /** |
| * gst_device_monitor_start: |
| * @monitor: A #GstDeviceMonitor |
| * |
| * Starts monitoring the devices. This will cause #GST_MESSAGE_DEVICE messages |
| * to be posted on the monitor's bus when devices are added or removed from |
| * the system. |
| * |
| * Since the #GstDeviceMonitor is a singleton, |
| * gst_device_monitor_start() may already have been called by another |
| * user of the object, gst_device_monitor_stop() needs to be called the same |
| * number of times. |
| * |
| * Returns: %TRUE if the device monitoring could be started |
| * |
| * Since: 1.4 |
| */ |
| |
| gboolean |
| gst_device_monitor_start (GstDeviceMonitor * monitor) |
| { |
| GstDeviceMonitorClass *klass; |
| gboolean ret = FALSE; |
| |
| g_return_val_if_fail (GST_IS_DEVICE_MONITOR (monitor), FALSE); |
| klass = GST_DEVICE_MONITOR_GET_CLASS (monitor); |
| |
| g_mutex_lock (&monitor->priv->start_lock); |
| |
| if (monitor->priv->started_count > 0) { |
| ret = TRUE; |
| goto started; |
| } |
| |
| if (klass->start) |
| ret = klass->start (monitor); |
| |
| if (ret) { |
| monitor->priv->started_count++; |
| gst_bus_set_flushing (monitor->priv->bus, FALSE); |
| } |
| |
| started: |
| |
| g_mutex_unlock (&monitor->priv->start_lock); |
| |
| return ret; |
| } |
| |
| /** |
| * gst_device_monitor_stop: |
| * @monitor: A #GstDeviceMonitor |
| * |
| * Decreases the use-count by one. If the use count reaches zero, this |
| * #GstDeviceMonitor will stop monitoring the devices. This needs to be |
| * called the same number of times that gst_device_monitor_start() was called. |
| * |
| * Since: 1.4 |
| */ |
| |
| void |
| gst_device_monitor_stop (GstDeviceMonitor * monitor) |
| { |
| GstDeviceMonitorClass *klass; |
| |
| g_return_if_fail (GST_IS_DEVICE_MONITOR (monitor)); |
| klass = GST_DEVICE_MONITOR_GET_CLASS (monitor); |
| |
| g_mutex_lock (&monitor->priv->start_lock); |
| |
| if (monitor->priv->started_count == 1) { |
| gst_bus_set_flushing (monitor->priv->bus, TRUE); |
| if (klass->stop) |
| klass->stop (monitor); |
| GST_OBJECT_LOCK (monitor); |
| g_list_free_full (monitor->devices, (GDestroyNotify) gst_object_unparent); |
| monitor->devices = NULL; |
| GST_OBJECT_UNLOCK (monitor); |
| } else if (monitor->priv->started_count < 1) { |
| g_critical ("Trying to stop a GstDeviceMonitor %s which is already stopped", |
| GST_OBJECT_NAME (monitor)); |
| } |
| |
| monitor->priv->started_count--; |
| g_mutex_unlock (&monitor->priv->start_lock); |
| } |
| |
| |
| /** |
| * gst_device_monitor_get_factory: |
| * @monitor: a #GstDeviceMonitor to request the device monitor factory of. |
| * |
| * Retrieves the factory that was used to create this device monitor. |
| * |
| * Returns: (transfer none): the #GstDeviceMonitorFactory used for creating this |
| * device monitor. no refcounting is needed. |
| * |
| * Since: 1.4 |
| */ |
| GstDeviceMonitorFactory * |
| gst_device_monitor_get_factory (GstDeviceMonitor * monitor) |
| { |
| g_return_val_if_fail (GST_IS_DEVICE_MONITOR (monitor), NULL); |
| |
| return GST_DEVICE_MONITOR_GET_CLASS (monitor)->factory; |
| } |
| |
| /** |
| * gst_device_monitor_can_monitor: |
| * @monitor: a #GstDeviceMonitor |
| * |
| * If this function returns %TRUE, then the device monitor can monitor if |
| * devices are added or removed. Otherwise, it can only do static probing. |
| * |
| * Returns: %TRUE if the #GstDeviceMonitor support monitoring, %FALSE otherwise |
| */ |
| gboolean |
| gst_device_monitor_can_monitor (GstDeviceMonitor * monitor) |
| { |
| GstDeviceMonitorClass *klass; |
| |
| g_return_val_if_fail (GST_IS_DEVICE_MONITOR (monitor), FALSE); |
| klass = GST_DEVICE_MONITOR_GET_CLASS (monitor); |
| |
| if (klass->start) |
| return TRUE; |
| else |
| return FALSE; |
| } |
| |
| /** |
| * gst_device_monitor_get_bus: |
| * @monitor: a #GstDeviceMonitor |
| * |
| * Gets the #GstBus of this #GstDeviceMonitor |
| * |
| * Returns: (transfer full): a #GstBus |
| * |
| * Since: 1.4 |
| */ |
| GstBus * |
| gst_device_monitor_get_bus (GstDeviceMonitor * monitor) |
| { |
| g_return_val_if_fail (GST_IS_DEVICE_MONITOR (monitor), NULL); |
| |
| return gst_object_ref (monitor->priv->bus); |
| } |
| |
| /** |
| * gst_device_monitor_device_add: |
| * @monitor: a #GstDeviceMonitor |
| * @device: (transfer full): a #GstDevice that has been added |
| * |
| * Posts a message on the monitor's #GstBus to inform applications that |
| * a new device has been added. |
| * |
| * This is for use by subclasses. |
| * |
| * Since: 1.4 |
| */ |
| void |
| gst_device_monitor_device_add (GstDeviceMonitor * monitor, GstDevice * device) |
| { |
| GstMessage *message; |
| |
| if (!gst_object_set_parent (GST_OBJECT (device), GST_OBJECT (monitor))) { |
| GST_WARNING_OBJECT (monitor, "Could not parent device %p to monitor," |
| " it already has a parent", device); |
| return; |
| } |
| |
| GST_OBJECT_LOCK (monitor); |
| monitor->devices = g_list_prepend (monitor->devices, gst_object_ref (device)); |
| GST_OBJECT_UNLOCK (monitor); |
| |
| message = gst_message_new_device_added (GST_OBJECT (monitor), device); |
| gst_bus_post (monitor->priv->bus, message); |
| gst_object_unref (device); |
| } |
| |
| |
| /** |
| * gst_device_monitor_device_remove: |
| * @monitor: a #GstDeviceMonitor |
| * @device: a #GstDevice that has been removed |
| * |
| * Posts a message on the monitor's #GstBus to inform applications that |
| * a device has been removed. |
| * |
| * This is for use by subclasses. |
| * |
| * Since: 1.4 |
| */ |
| void |
| gst_device_monitor_device_remove (GstDeviceMonitor * monitor, |
| GstDevice * device) |
| { |
| GstMessage *message; |
| GList *item; |
| |
| GST_OBJECT_LOCK (monitor); |
| item = g_list_find (monitor->devices, device); |
| if (item) { |
| monitor->devices = g_list_delete_link (monitor->devices, item); |
| } |
| GST_OBJECT_UNLOCK (monitor); |
| |
| message = gst_message_new_device_removed (GST_OBJECT (monitor), device); |
| g_signal_emit_by_name (device, "removed"); |
| gst_bus_post (monitor->priv->bus, message); |
| if (item) |
| gst_object_unparent (GST_OBJECT (device)); |
| } |