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authorMichal Ratajsky <[email protected]>2014-08-12 05:06:12 +0200
committerMichal Ratajsky <[email protected]>2014-08-12 05:06:12 +0200
commit1e1847069eb58c2b62f2b3c11e1e9adf3a17ebde (patch)
tree4bcd30db2bdf4032c4a49844570ce4227cf2510e /backends/alsa/alsa-device.c
parent7396148c328d9f2a0d933374547c7e93a46b8efa (diff)
parent6c6d4239ddc807e922df3874654f99eea291aadb (diff)
downloadlibmatemixer-1e1847069eb58c2b62f2b3c11e1e9adf3a17ebde.tar.bz2
libmatemixer-1e1847069eb58c2b62f2b3c11e1e9adf3a17ebde.tar.xz
Merge branch 'oss-alsa'
Diffstat (limited to 'backends/alsa/alsa-device.c')
-rw-r--r--backends/alsa/alsa-device.c941
1 files changed, 941 insertions, 0 deletions
diff --git a/backends/alsa/alsa-device.c b/backends/alsa/alsa-device.c
new file mode 100644
index 0000000..5acc6f5
--- /dev/null
+++ b/backends/alsa/alsa-device.c
@@ -0,0 +1,941 @@
+/*
+ * Copyright (C) 2014 Michal Ratajsky <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the licence, 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <strings.h>
+#include <glib.h>
+#include <glib/gi18n.h>
+#include <glib-object.h>
+#include <alsa/asoundlib.h>
+#include <libmatemixer/matemixer.h>
+
+#include "alsa-constants.h"
+#include "alsa-device.h"
+#include "alsa-element.h"
+#include "alsa-stream.h"
+#include "alsa-stream-control.h"
+#include "alsa-stream-input-control.h"
+#include "alsa-stream-output-control.h"
+#include "alsa-switch.h"
+#include "alsa-switch-option.h"
+#include "alsa-toggle.h"
+
+#define ALSA_DEVICE_ICON "audio-card"
+
+struct _AlsaDevicePrivate
+{
+ snd_mixer_t *handle;
+ GMainContext *context;
+ GMutex mutex;
+ GCond cond;
+ AlsaStream *input;
+ AlsaStream *output;
+ GHashTable *switches;
+ gboolean events_pending;
+};
+
+enum {
+ CLOSED,
+ N_SIGNALS
+};
+
+static guint signals[N_SIGNALS] = { 0, };
+
+static void alsa_device_class_init (AlsaDeviceClass *klass);
+static void alsa_device_init (AlsaDevice *device);
+static void alsa_device_dispose (GObject *object);
+static void alsa_device_finalize (GObject *object);
+
+G_DEFINE_TYPE (AlsaDevice, alsa_device, MATE_MIXER_TYPE_DEVICE)
+
+static MateMixerSwitch *alsa_device_get_switch (MateMixerDevice *mmd,
+ const gchar *name);
+
+static GList * alsa_device_list_streams (MateMixerDevice *mmd);
+static GList * alsa_device_list_switches (MateMixerDevice *mmd);
+
+static gboolean add_stream_input_control (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+static gboolean add_stream_output_control (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+
+static gboolean add_switch (AlsaDevice *device,
+ AlsaStream *stream,
+ snd_mixer_elem_t *el);
+
+static gboolean add_device_switch (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+
+static gboolean add_stream_input_switch (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+static gboolean add_stream_output_switch (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+
+static gboolean add_stream_input_toggle (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+static gboolean add_stream_output_toggle (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+
+static void load_element (AlsaDevice *device,
+ snd_mixer_elem_t *el);
+
+static void load_elements_by_name (AlsaDevice *device,
+ const gchar *name);
+
+static void remove_elements_by_name (AlsaDevice *device,
+ const gchar *name);
+
+static void handle_poll (AlsaDevice *device);
+
+static gboolean handle_process_events (AlsaDevice *device);
+
+static int handle_callback (snd_mixer_t *handle,
+ guint mask,
+ snd_mixer_elem_t *el);
+static int handle_element_callback (snd_mixer_elem_t *el,
+ guint mask);
+
+static void close_device (AlsaDevice *device);
+
+static gchar * get_element_name (snd_mixer_elem_t *el);
+static void get_control_info (snd_mixer_elem_t *el,
+ gchar **name,
+ gchar **label,
+ MateMixerStreamControlRole *role);
+
+static void get_switch_info (snd_mixer_elem_t *el,
+ gchar **name,
+ gchar **label);
+
+static void
+alsa_device_class_init (AlsaDeviceClass *klass)
+{
+ GObjectClass *object_class;
+ MateMixerDeviceClass *device_class;
+
+ object_class = G_OBJECT_CLASS (klass);
+ object_class->dispose = alsa_device_dispose;
+ object_class->finalize = alsa_device_finalize;
+
+ device_class = MATE_MIXER_DEVICE_CLASS (klass);
+ device_class->get_switch = alsa_device_get_switch;
+ device_class->list_streams = alsa_device_list_streams;
+ device_class->list_switches = alsa_device_list_switches;
+
+ signals[CLOSED] =
+ g_signal_new ("closed",
+ G_TYPE_FROM_CLASS (object_class),
+ G_SIGNAL_RUN_LAST,
+ G_STRUCT_OFFSET (AlsaDeviceClass, closed),
+ NULL,
+ NULL,
+ g_cclosure_marshal_VOID__VOID,
+ G_TYPE_NONE,
+ 0,
+ G_TYPE_NONE);
+
+ g_type_class_add_private (object_class, sizeof (AlsaDevicePrivate));
+}
+
+static void
+alsa_device_init (AlsaDevice *device)
+{
+ device->priv = G_TYPE_INSTANCE_GET_PRIVATE (device,
+ ALSA_TYPE_DEVICE,
+ AlsaDevicePrivate);
+
+ device->priv->switches = g_hash_table_new_full (g_str_hash,
+ g_str_equal,
+ g_free,
+ g_object_unref);
+
+ device->priv->context = g_main_context_ref_thread_default ();
+
+ g_mutex_init (&device->priv->mutex);
+ g_cond_init (&device->priv->cond);
+}
+
+static void
+alsa_device_dispose (GObject *object)
+{
+ AlsaDevice *device;
+
+ device = ALSA_DEVICE (object);
+
+ g_clear_object (&device->priv->input);
+ g_clear_object (&device->priv->output);
+
+ g_hash_table_remove_all (device->priv->switches);
+
+ G_OBJECT_CLASS (alsa_device_parent_class)->dispose (object);
+}
+
+static void
+alsa_device_finalize (GObject *object)
+{
+ AlsaDevice *device;
+
+ device = ALSA_DEVICE (object);
+
+ g_mutex_clear (&device->priv->mutex);
+ g_cond_clear (&device->priv->cond);
+
+ g_hash_table_unref (device->priv->switches);
+ g_main_context_unref (device->priv->context);
+
+ if (device->priv->handle != NULL)
+ snd_mixer_close (device->priv->handle);
+
+ G_OBJECT_CLASS (alsa_device_parent_class)->dispose (object);
+}
+
+AlsaDevice *
+alsa_device_new (const gchar *name, const gchar *label)
+{
+ AlsaDevice *device;
+ gchar *stream_name;
+
+ g_return_val_if_fail (name != NULL, NULL);
+ g_return_val_if_fail (label != NULL, NULL);
+
+ device = g_object_new (ALSA_TYPE_DEVICE,
+ "name", name,
+ "label", label,
+ "icon", ALSA_DEVICE_ICON,
+ NULL);
+
+ /* Create input and output streams, they will exist the whole time, but
+ * the added and removed signals will be emitted when the first control or
+ * switch is added or the last one removed */
+ stream_name = g_strdup_printf ("alsa-input-%s", name);
+ device->priv->input = alsa_stream_new (stream_name,
+ MATE_MIXER_DEVICE (device),
+ MATE_MIXER_STREAM_INPUT);
+ g_free (stream_name);
+
+ stream_name = g_strdup_printf ("alsa-output-%s", name);
+ device->priv->output = alsa_stream_new (stream_name,
+ MATE_MIXER_DEVICE (device),
+ MATE_MIXER_STREAM_OUTPUT);
+ g_free (stream_name);
+
+ return device;
+}
+
+gboolean
+alsa_device_open (AlsaDevice *device)
+{
+ snd_mixer_t *handle;
+ const gchar *name;
+ gint ret;
+
+ g_return_val_if_fail (ALSA_IS_DEVICE (device), FALSE);
+ g_return_val_if_fail (device->priv->handle == NULL, FALSE);
+
+ name = mate_mixer_device_get_name (MATE_MIXER_DEVICE (device));
+
+ g_debug ("Opening device %s (%s)",
+ name,
+ mate_mixer_device_get_label (MATE_MIXER_DEVICE (device)));
+
+ /* Open the mixer for the current device */
+ ret = snd_mixer_open (&handle, 0);
+ if (ret < 0) {
+ g_warning ("Failed to open mixer: %s", snd_strerror (ret));
+ return FALSE;
+ }
+ ret = snd_mixer_attach (handle, name);
+ if (ret < 0) {
+ g_warning ("Failed to attach mixer to %s: %s",
+ name,
+ snd_strerror (ret));
+
+ snd_mixer_close (handle);
+ return FALSE;
+ }
+ ret = snd_mixer_selem_register (handle, NULL, NULL);
+ if (ret < 0) {
+ g_warning ("Failed to register simple element for %s: %s",
+ name,
+ snd_strerror (ret));
+
+ snd_mixer_close (handle);
+ return FALSE;
+ }
+ ret = snd_mixer_load (handle);
+ if (ret < 0) {
+ g_warning ("Failed to load mixer elements for %s: %s",
+ name,
+ snd_strerror (ret));
+
+ snd_mixer_close (handle);
+ return FALSE;
+ }
+
+ device->priv->handle = handle;
+ return TRUE;
+}
+
+void
+alsa_device_load (AlsaDevice *device)
+{
+ GThread *thread;
+ GError *error = NULL;
+ snd_mixer_elem_t *el;
+
+ g_return_if_fail (ALSA_IS_DEVICE (device));
+ g_return_if_fail (device->priv->handle != NULL);
+
+ /* Process the mixer elements */
+ el = snd_mixer_first_elem (device->priv->handle);
+ while (el != NULL) {
+ load_element (device, el);
+
+ el = snd_mixer_elem_next (el);
+ }
+
+ /* Set callback for ALSA events */
+ snd_mixer_set_callback (device->priv->handle, handle_callback);
+ snd_mixer_set_callback_private (device->priv->handle, device);
+
+ /* Start the polling thread */
+ thread = g_thread_try_new ("matemixer-alsa-poll",
+ (GThreadFunc) handle_poll,
+ device,
+ &error);
+ if (thread == NULL) {
+ /* The error is not treated as fatal, because without the polling
+ * thread we still have most of the functionality */
+ g_warning ("Failed to create poll thread: %s", error->message);
+ g_error_free (error);
+ } else
+ g_thread_unref (thread);
+}
+
+AlsaStream *
+alsa_device_get_input_stream (AlsaDevice *device)
+{
+ g_return_val_if_fail (ALSA_IS_DEVICE (device), NULL);
+
+ /* Normally controlless streams should not exist, here we simulate the
+ * behaviour for the owning instance */
+ if (alsa_stream_is_empty (device->priv->input) == FALSE)
+ return device->priv->input;
+
+ return NULL;
+}
+
+AlsaStream *
+alsa_device_get_output_stream (AlsaDevice *device)
+{
+ g_return_val_if_fail (ALSA_IS_DEVICE (device), NULL);
+
+ /* Normally controlless streams should not exist, here we simulate the
+ * behaviour for the owning instance */
+ if (alsa_stream_is_empty (device->priv->output) == FALSE)
+ return device->priv->output;
+
+ return NULL;
+}
+
+static gboolean
+add_element (AlsaDevice *device, AlsaStream *stream, AlsaElement *element)
+{
+ gboolean added = FALSE;
+
+ if (alsa_element_load (element) == FALSE)
+ return FALSE;
+
+ if (stream != NULL) {
+ gboolean empty = FALSE;
+
+ if (alsa_stream_is_empty (stream) == TRUE) {
+ const gchar *name =
+ mate_mixer_stream_get_name (MATE_MIXER_STREAM (stream));
+
+ /* Pretend the stream has just been created now that we are adding
+ * the first control */
+ g_signal_emit_by_name (G_OBJECT (device),
+ "stream-added",
+ name);
+ empty = TRUE;
+ }
+
+ if (ALSA_IS_STREAM_CONTROL (element)) {
+ alsa_stream_add_control (stream, ALSA_STREAM_CONTROL (element));
+
+ /* If this is the first control, set it as the default one.
+ * The controls often seem to come in the order of importance, but this is
+ * driver specific, so we may later see if there is another control which
+ * better matches the default. */
+ if (empty == TRUE)
+ alsa_stream_set_default_control (stream, ALSA_STREAM_CONTROL (element));
+
+ added = TRUE;
+ } else if (ALSA_IS_SWITCH (element)) {
+ /* Switch belonging to a stream */
+ alsa_stream_add_switch (stream, ALSA_SWITCH (element));
+ added = TRUE;
+ }
+ } else if (ALSA_IS_SWITCH (element)) {
+ /* Switch belonging to the device */
+ const gchar *name =
+ mate_mixer_switch_get_name (MATE_MIXER_SWITCH (element));
+
+ g_hash_table_insert (device->priv->switches,
+ g_strdup (name),
+ g_object_ref (element));
+
+ g_signal_emit_by_name (G_OBJECT (device),
+ "switch-added",
+ name);
+ added = TRUE;
+ }
+
+ if G_LIKELY (added == TRUE) {
+ snd_mixer_elem_t *el = alsa_element_get_snd_element (element);
+
+ snd_mixer_elem_set_callback (el, handle_element_callback);
+ snd_mixer_elem_set_callback_private (el, device);
+ }
+ return added;
+}
+
+static MateMixerSwitch *
+alsa_device_get_switch (MateMixerDevice *mmd, const gchar *name)
+{
+ g_return_val_if_fail (ALSA_IS_DEVICE (mmd), NULL);
+ g_return_val_if_fail (name != NULL, NULL);
+
+ return g_hash_table_lookup (ALSA_DEVICE (mmd)->priv->switches, name);
+}
+
+static GList *
+alsa_device_list_streams (MateMixerDevice *mmd)
+{
+ AlsaDevice *device;
+ GList *list = NULL;
+
+ g_return_val_if_fail (ALSA_IS_DEVICE (mmd), NULL);
+
+ device = ALSA_DEVICE (mmd);
+
+ if (device->priv->output != NULL)
+ list = g_list_prepend (list, g_object_ref (device->priv->output));
+ if (device->priv->input != NULL)
+ list = g_list_prepend (list, g_object_ref (device->priv->input));
+
+ return list;
+}
+
+static GList *
+alsa_device_list_switches (MateMixerDevice *mmd)
+{
+ GList *list;
+
+ g_return_val_if_fail (ALSA_IS_DEVICE (mmd), NULL);
+
+ /* Convert the hash table to a linked list, this list is expected to be
+ * cached in the main library */
+ list = g_hash_table_get_values (ALSA_DEVICE (mmd)->priv->switches);
+ if (list != NULL)
+ g_list_foreach (list, (GFunc) g_object_ref, NULL);
+
+ return list;
+}
+
+static gboolean
+add_stream_input_control (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ AlsaStreamControl *control;
+ gchar *name;
+ gchar *label;
+ MateMixerStreamControlRole role;
+
+ get_control_info (el, &name, &label, &role);
+
+ g_debug ("Found device %s input control %s",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)),
+ label);
+
+ control = alsa_stream_input_control_new (name, label, role);
+ g_free (name);
+ g_free (label);
+
+ alsa_element_set_snd_element (ALSA_ELEMENT (control), el);
+
+ if (add_element (device, device->priv->input, ALSA_ELEMENT (control)) == FALSE) {
+ g_object_unref (control);
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static gboolean
+add_stream_output_control (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ AlsaStreamControl *control;
+ gchar *label;
+ gchar *name;
+ MateMixerStreamControlRole role;
+
+ get_control_info (el, &name, &label, &role);
+
+ g_debug ("Found device %s output control %s",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)),
+ label);
+
+ control = alsa_stream_output_control_new (name, label, role);
+ g_free (name);
+ g_free (label);
+
+ alsa_element_set_snd_element (ALSA_ELEMENT (control), el);
+
+ if (add_element (device, device->priv->output, ALSA_ELEMENT (control)) == FALSE) {
+ g_object_unref (control);
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static AlsaToggle *
+create_toggle (AlsaDevice *device, snd_mixer_elem_t *el, AlsaToggleType type)
+{
+ AlsaToggle *toggle;
+ AlsaSwitchOption *on;
+ AlsaSwitchOption *off;
+ gchar *name;
+ gchar *label;
+
+ on = alsa_switch_option_new ("On", _("On"), NULL, 1);
+ off = alsa_switch_option_new ("Off", _("Off"), NULL, 0);
+
+ get_switch_info (el, &name, &label);
+ toggle = alsa_toggle_new (name,
+ label,
+ type,
+ on, off);
+ g_free (name);
+ g_free (label);
+
+ alsa_element_set_snd_element (ALSA_ELEMENT (toggle), el);
+
+ g_object_unref (on);
+ g_object_unref (off);
+
+ return toggle;
+}
+
+static gboolean
+add_switch (AlsaDevice *device, AlsaStream *stream, snd_mixer_elem_t *el)
+{
+ AlsaElement *element = NULL;
+ GList *options = NULL;
+ gchar *name;
+ gchar *label;
+ gchar item[128];
+ guint i;
+ gint count;
+ gint ret;
+
+ count = snd_mixer_selem_get_enum_items (el);
+ if G_UNLIKELY (count <= 0) {
+ g_debug ("Skipping mixer switch %s with %d items",
+ snd_mixer_selem_get_name (el),
+ count);
+ return FALSE;
+ }
+
+ for (i = 0; i < count; i++) {
+ ret = snd_mixer_selem_get_enum_item_name (el, i,
+ sizeof (item),
+ item);
+ if G_LIKELY (ret == 0)
+ options = g_list_prepend (options,
+ alsa_switch_option_new (item, item, NULL, i));
+ else
+ g_warning ("Failed to read switch item name: %s", snd_strerror (ret));
+ }
+
+ get_switch_info (el, &name, &label);
+
+ /* Takes ownership of options */
+ element = ALSA_ELEMENT (alsa_switch_new (name, label, g_list_reverse (options)));
+ g_free (name);
+ g_free (label);
+
+ alsa_element_set_snd_element (element, el);
+
+ if (add_element (device, stream, element) == FALSE) {
+ g_object_unref (element);
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static gboolean
+add_device_switch (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ g_debug ("Reading device %s switch %s (%d items)",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)),
+ snd_mixer_selem_get_name (el),
+ snd_mixer_selem_get_enum_items (el));
+
+ return add_switch (device, NULL, el);
+}
+
+static gboolean
+add_stream_input_switch (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ g_debug ("Reading device %s input switch %s (%d items)",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)),
+ snd_mixer_selem_get_name (el),
+ snd_mixer_selem_get_enum_items (el));
+
+ return add_switch (device, device->priv->input, el);
+}
+
+static gboolean
+add_stream_output_switch (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ g_debug ("Reading device %s output switch %s (%d items)",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)),
+ snd_mixer_selem_get_name (el),
+ snd_mixer_selem_get_enum_items (el));
+
+ return add_switch (device, device->priv->output, el);
+}
+
+static gboolean
+add_stream_input_toggle (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ AlsaToggle *toggle;
+
+ g_debug ("Reading device %s input toggle %s",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)),
+ snd_mixer_selem_get_name (el));
+
+ toggle = create_toggle (device, el, ALSA_TOGGLE_CAPTURE);
+
+ if (add_element (device, device->priv->input, ALSA_ELEMENT (toggle)) == FALSE) {
+ g_object_unref (toggle);
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static gboolean
+add_stream_output_toggle (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ AlsaToggle *toggle;
+
+ g_debug ("Reading device %s output toggle %s",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)),
+ snd_mixer_selem_get_name (el));
+
+ toggle = create_toggle (device, el, ALSA_TOGGLE_PLAYBACK);
+
+ if (add_element (device, device->priv->output, ALSA_ELEMENT (toggle)) == FALSE) {
+ g_object_unref (toggle);
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static void
+load_element (AlsaDevice *device, snd_mixer_elem_t *el)
+{
+ gboolean cvolume = FALSE;
+ gboolean pvolume = FALSE;
+
+ if (snd_mixer_selem_is_enumerated (el) == 1) {
+ gboolean cenum = FALSE;
+ gboolean penum = FALSE;
+
+ if (snd_mixer_selem_is_enum_capture (el) == 1)
+ cenum = TRUE;
+ if (snd_mixer_selem_is_enum_playback (el) == 1)
+ penum = TRUE;
+
+ /* Enumerated controls which are not marked as capture or playback
+ * are considered to be a part of the whole device, although sometimes
+ * this is incorrectly reported by the driver */
+ if (cenum == FALSE && penum == FALSE) {
+ add_device_switch (device, el);
+ }
+ else if (cenum == TRUE)
+ add_stream_input_switch (device, el);
+ else if (penum == TRUE)
+ add_stream_output_switch (device, el);
+ }
+
+ if (snd_mixer_selem_has_capture_volume (el) == 1 ||
+ snd_mixer_selem_has_common_volume (el) == 1)
+ cvolume = TRUE;
+ if (snd_mixer_selem_has_playback_volume (el) == 1 ||
+ snd_mixer_selem_has_common_volume (el) == 1)
+ pvolume = TRUE;
+
+ if (cvolume == FALSE && pvolume == FALSE) {
+ /* Control without volume and with a switch are modelled as toggles */
+ if (snd_mixer_selem_has_capture_switch (el) == 1)
+ add_stream_input_toggle (device, el);
+
+ if (snd_mixer_selem_has_playback_switch (el) == 1)
+ add_stream_output_toggle (device, el);
+ } else {
+ if (cvolume == TRUE)
+ add_stream_input_control (device, el);
+ if (pvolume == TRUE)
+ add_stream_output_control (device, el);
+ }
+}
+
+static void
+load_elements_by_name (AlsaDevice *device, const gchar *name)
+{
+ AlsaElement *element;
+
+ alsa_stream_load_elements (device->priv->input, name);
+ alsa_stream_load_elements (device->priv->output, name);
+
+ element = g_hash_table_lookup (device->priv->switches, name);
+ if (element != NULL)
+ alsa_element_load (element);
+}
+
+static void
+remove_elements_by_name (AlsaDevice *device, const gchar *name)
+{
+ if (alsa_stream_remove_elements (device->priv->input, name) == TRUE) {
+ /* Removing last stream element "removes" the stream */
+ if (alsa_stream_is_empty (device->priv->input) == TRUE) {
+ const gchar *stream_name =
+ mate_mixer_stream_get_name (MATE_MIXER_STREAM (device->priv->input));
+
+ g_signal_emit_by_name (G_OBJECT (device),
+ "stream-removed",
+ stream_name);
+ }
+ }
+
+ if (alsa_stream_remove_elements (device->priv->output, name) == TRUE) {
+ /* Removing last stream element "removes" the stream */
+ if (alsa_stream_is_empty (device->priv->output) == TRUE) {
+ const gchar *stream_name =
+ mate_mixer_stream_get_name (MATE_MIXER_STREAM (device->priv->output));
+
+ g_signal_emit_by_name (G_OBJECT (device),
+ "stream-removed",
+ stream_name);
+ }
+ }
+
+ if (g_hash_table_remove (device->priv->switches, name) == TRUE)
+ g_signal_emit_by_name (G_OBJECT (device),
+ "switch-removed",
+ name);
+}
+
+static void
+handle_poll (AlsaDevice *device)
+{
+ /* This function is called in a worker thread. It is supposed to wait for
+ * ALSA events and call handle_process_events(). Processing the events might
+ * result in emitting the CLOSED signal and unreffing the instance in the
+ * owner, so keep an extra reference during the lifetime of the thread. */
+ g_object_ref (device);
+
+ while (TRUE) {
+ gint ret = snd_mixer_wait (device->priv->handle, -1);
+ if (ret < 0) {
+ if (ret == EINTR)
+ continue;
+ break;
+ }
+
+ device->priv->events_pending = TRUE;
+
+ /* Process the events in the main thread because most events end up
+ * emitting signals */
+ g_main_context_invoke (device->priv->context,
+ (GSourceFunc) handle_process_events,
+ device);
+
+ g_mutex_lock (&device->priv->mutex);
+
+ /* Use a GCond to wait until the events are processed. The processing
+ * function may be called any time later in the main loop and snd_mixer_wait()
+ * returns instantly while there are pending events. Without the wait,
+ * g_main_context_invoke() could be called repeatedly to create idle sources
+ * until the first idle source function is called. */
+ while (device->priv->events_pending == TRUE)
+ g_cond_wait (&device->priv->cond, &device->priv->mutex);
+
+ g_mutex_unlock (&device->priv->mutex);
+
+ /* Exit the thread if the processing function closed the device */
+ if (device->priv->handle == NULL)
+ break;
+ }
+
+ g_debug ("Terminating poll thread for device %s",
+ mate_mixer_device_get_name (MATE_MIXER_DEVICE (device)));
+
+ g_object_unref (device);
+}
+
+static gboolean
+handle_process_events (AlsaDevice *device)
+{
+ g_mutex_lock (&device->priv->mutex);
+
+ if (device->priv->handle != NULL) {
+ gint ret = snd_mixer_handle_events (device->priv->handle);
+ if (ret < 0)
+ close_device (device);
+ }
+
+ device->priv->events_pending = FALSE;
+
+ g_cond_signal (&device->priv->cond);
+ g_mutex_unlock (&device->priv->mutex);
+
+ return G_SOURCE_REMOVE;
+}
+
+/* ALSA has a per-mixer callback and per-element callback, per-mixer callback
+ * is only used for added elements and per-element callback for all the
+ * other messages (no, the documentation doesn't say anything about that). */
+static int
+handle_callback (snd_mixer_t *handle, guint mask, snd_mixer_elem_t *el)
+{
+ if (mask & SND_CTL_EVENT_MASK_ADD) {
+ AlsaDevice *device = snd_mixer_get_callback_private (handle);
+
+ load_element (device, el);
+ }
+ return 0;
+}
+
+static int
+handle_element_callback (snd_mixer_elem_t *el, guint mask)
+{
+ AlsaDevice *device;
+ gchar *name;
+
+ device = snd_mixer_elem_get_callback_private (el);
+ name = get_element_name (el);
+
+ if (mask == SND_CTL_EVENT_MASK_REMOVE) {
+ /* Make sure this function is not called again with the element */
+ snd_mixer_elem_set_callback_private (el, NULL);
+ snd_mixer_elem_set_callback (el, NULL);
+
+ remove_elements_by_name (device, name);
+ } else {
+ if (mask & SND_CTL_EVENT_MASK_INFO) {
+ remove_elements_by_name (device, name);
+ load_element (device, el);
+ }
+ if (mask & SND_CTL_EVENT_MASK_VALUE)
+ load_elements_by_name (device, name);
+ }
+ g_free (name);
+
+ return 0;
+}
+
+static void
+close_device (AlsaDevice *device)
+{
+ if (device->priv->handle != NULL) {
+ snd_mixer_close (device->priv->handle);
+ device->priv->handle = NULL;
+ }
+
+ /* This signal tells the owner that the device has been closed voluntarily
+ * from within the instance */
+ g_signal_emit (G_OBJECT (device), signals[CLOSED], 0);
+}
+
+static gchar *
+get_element_name (snd_mixer_elem_t *el)
+{
+ return g_strdup_printf ("%s-%d",
+ snd_mixer_selem_get_name (el),
+ snd_mixer_selem_get_index (el));
+}
+
+static void
+get_control_info (snd_mixer_elem_t *el,
+ gchar **name,
+ gchar **label,
+ MateMixerStreamControlRole *role)
+{
+ MateMixerStreamControlRole r = MATE_MIXER_STREAM_CONTROL_ROLE_UNKNOWN;
+ const gchar *n;
+ const gchar *l = NULL;
+ gint i;
+
+ n = snd_mixer_selem_get_name (el);
+
+ for (i = 0; alsa_controls[i].name != NULL; i++)
+ if (strcmp (n, alsa_controls[i].name) == 0) {
+ l = alsa_controls[i].label;
+ r = alsa_controls[i].role;
+ break;
+ }
+
+ *name = get_element_name (el);
+ if (l != NULL)
+ *label = g_strdup (l);
+ else
+ *label = g_strdup (n);
+
+ *role = r;
+}
+
+static void
+get_switch_info (snd_mixer_elem_t *el,
+ gchar **name,
+ gchar **label)
+{
+ // MateMixerStreamControlRole r = MATE_MIXER_STREAM_CONTROL_ROLE_UNKNOWN;
+ const gchar *n;
+ const gchar *l = NULL;
+ // gint i;
+
+ n = snd_mixer_selem_get_name (el);
+
+ // TODO provide translated label and flags
+
+/*
+ for (i = 0; alsa_controls[i].name != NULL; i++)
+ if (strcmp (n, alsa_controls[i].name) == 0) {
+ l = alsa_controls[i].label;
+ r = alsa_controls[i].role;
+ break;
+ }
+*/
+ *name = get_element_name (el);
+ if (l != NULL)
+ *label = g_strdup (l);
+ else
+ *label = g_strdup (n);
+
+ // *role = r;
+}