Alsa based volume control API, stealed from gnome-settings-daemon. #8375

2008-09-13 13:45:47 +02:00
parent 388f74a56d
commit be014cc270
8 changed files with 641 additions and 1 deletions
@@ -0,0 +1,329 @@
+/* acme-volume-alsa.c
+
+   Copyright (C) 2002, 2003 Bastien Nocera
+
+   The Gnome 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.
+
+   The Gnome 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 the Gnome Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+
+   Author: Bastien Nocera <hadess@hadess.net>
+ */
+
+#ifdef HAVE_CONFIG
+#include "config.h"
+#endif
+
+#include "acme-volume-alsa.h"
+
+#include <alsa/asoundlib.h>
+
+#ifndef DEFAULT_CARD
+#define DEFAULT_CARD "default"
+#endif
+
+#undef LOG
+#ifdef LOG
+#define D(x...) g_message (x)
+#else
+#define D(x...)
+#endif
+
+#define ROUND(x) ((x - (int)x > 0.5) ? x+1 : x)
+
+struct AcmeVolumeAlsaPrivate
+{
+	long pmin, pmax;
+	gboolean has_mute, has_master;
+	snd_mixer_t *handle;
+	snd_mixer_elem_t *elem;
+	int saved_volume;
+	guint timer_id;
+};
+
+static int acme_volume_alsa_get_volume (AcmeVolume *self);
+static void acme_volume_alsa_set_volume (AcmeVolume *self, int val);
+static gboolean acme_volume_alsa_open (AcmeVolumeAlsa *self);
+static void acme_volume_alsa_close (AcmeVolumeAlsa *self);
+static gboolean acme_volume_alsa_close_real (AcmeVolumeAlsa *self);
+
+G_DEFINE_TYPE (AcmeVolumeAlsa, acme_volume_alsa, ACME_TYPE_VOLUME)
+
+static void
+acme_volume_alsa_finalize (GObject *object)
+{
+	AcmeVolumeAlsa *self;
+
+	self = ACME_VOLUME_ALSA (object);
+
+	if (self->_priv)
+	{
+		if (self->_priv->timer_id != 0)
+		{
+			g_source_remove (self->_priv->timer_id);
+			self->_priv->timer_id = 0;
+		}
+
+		acme_volume_alsa_close_real (self);
+		g_free (self->_priv);
+		self->_priv = NULL;
+	}
+
+	G_OBJECT_CLASS (acme_volume_alsa_parent_class)->finalize (object);
+}
+
+static void
+acme_volume_alsa_set_mute (AcmeVolume *vol, gboolean val)
+{
+	AcmeVolumeAlsa *self = (AcmeVolumeAlsa *) vol;
+
+	if (acme_volume_alsa_open (self) == FALSE)
+		return;
+
+	/* If we have a hardware mute */
+	if (self->_priv->has_mute)
+	{
+		snd_mixer_selem_set_playback_switch_all
+			(self->_priv->elem, !val);
+		acme_volume_alsa_close (self);
+		return;
+	}
+
+	acme_volume_alsa_close (self);
+
+	/* If we don't */
+	if (val == TRUE)
+	{
+		self->_priv->saved_volume = acme_volume_alsa_get_volume (vol);
+		acme_volume_alsa_set_volume (vol, 0);
+	} else {
+		if (self->_priv->saved_volume != -1)
+			acme_volume_alsa_set_volume (vol,
+					self->_priv->saved_volume);
+	}
+}
+
+static gboolean
+acme_volume_alsa_get_mute (AcmeVolume *vol)
+{
+	AcmeVolumeAlsa *self = (AcmeVolumeAlsa *) vol;
+	int ival;
+
+	if (acme_volume_alsa_open (self) == FALSE)
+		return FALSE;
+
+	if (self->_priv->has_mute)
+	{
+		snd_mixer_selem_get_playback_switch(self->_priv->elem,
+				SND_MIXER_SCHN_FRONT_LEFT, &ival);
+
+		acme_volume_alsa_close (self);
+
+		return !ival;
+	} else {
+		acme_volume_alsa_close (self);
+
+		return (acme_volume_alsa_get_volume (vol) == 0);
+	}
+}
+
+static int
+acme_volume_alsa_get_volume (AcmeVolume *vol)
+{
+	AcmeVolumeAlsa *self = (AcmeVolumeAlsa *) vol;
+	long lval, rval;
+	int tmp;
+	float alsa_vol;
+
+	if (acme_volume_alsa_open (self) == FALSE)
+		return 0;
+
+	snd_mixer_selem_get_playback_volume(self->_priv->elem,
+			SND_MIXER_SCHN_FRONT_LEFT, &lval);
+	snd_mixer_selem_get_playback_volume(self->_priv->elem,
+			SND_MIXER_SCHN_FRONT_RIGHT, &rval);
+
+	acme_volume_alsa_close (self);
+
+	alsa_vol = (lval + rval) / 2;
+	alsa_vol = alsa_vol * 100 / (self->_priv->pmax - self->_priv->pmin);
+	tmp = ROUND (alsa_vol);
+
+	return tmp;
+}
+
+static void
+acme_volume_alsa_set_volume (AcmeVolume *vol, int val)
+{
+	AcmeVolumeAlsa *self = (AcmeVolumeAlsa *) vol;
+	float volume;
+	int tmp;
+
+	if (acme_volume_alsa_open (self) == FALSE)
+		return;
+
+	volume = (float) val / 100 * (self->_priv->pmax - self->_priv->pmin);
+	volume = CLAMP (volume, self->_priv->pmin, self->_priv->pmax);
+	tmp = ROUND (volume);
+
+	snd_mixer_selem_set_playback_volume_all (self->_priv->elem, tmp);
+
+	acme_volume_alsa_close (self);
+}
+
+static int
+acme_volume_alsa_get_threshold (AcmeVolume *vol)
+{
+	AcmeVolumeAlsa *self = (AcmeVolumeAlsa *) vol;
+	int steps;
+
+	if (acme_volume_alsa_open (self) == FALSE)
+		return 1;
+
+	acme_volume_alsa_close (self);
+
+	steps = self->_priv->pmax - self->_priv->pmin;
+	return (steps > 0) ? 100 / steps + 1 : 1;
+}
+
+static gboolean
+acme_volume_alsa_close_real (AcmeVolumeAlsa *self)
+{
+	if (self->_priv == NULL)
+		return FALSE;
+
+	if (self->_priv->handle != NULL)
+	{
+		snd_mixer_detach (self->_priv->handle, DEFAULT_CARD);
+		snd_mixer_free (self->_priv->handle);
+		self->_priv->handle = NULL;
+		self->_priv->elem = NULL;
+	}
+
+	self->_priv->timer_id = 0;
+
+	return FALSE;
+}
+
+static gboolean
+acme_volume_alsa_open (AcmeVolumeAlsa *self)
+{
+	snd_mixer_selem_id_t *sid;
+	snd_mixer_t *handle;
+	snd_mixer_elem_t *elem;
+
+	if (self->_priv->timer_id != 0)
+	{
+		g_source_remove (self->_priv->timer_id);
+		self->_priv->timer_id = 0;
+		return TRUE;
+	}
+
+	/* open the mixer */
+	if (snd_mixer_open (&handle, 0) < 0)
+	{
+		D("snd_mixer_open");
+		return FALSE;
+	}
+	/* attach the handle to the default card */
+	if (snd_mixer_attach (handle, DEFAULT_CARD) <0)
+	{
+		D("snd_mixer_attach");
+		goto bail;
+	}
+	/* ? */
+	if (snd_mixer_selem_register (handle, NULL, NULL) < 0)
+	{
+		D("snd_mixer_selem_register");
+		goto bail;
+	}
+	if (snd_mixer_load (handle) < 0)
+	{
+		D("snd_mixer_load");
+		goto bail;
+	}
+
+	snd_mixer_selem_id_alloca (&sid);
+	snd_mixer_selem_id_set_name (sid, "Master");
+	elem = snd_mixer_find_selem (handle, sid);
+	if (!elem)
+	{
+		snd_mixer_selem_id_alloca (&sid);
+		snd_mixer_selem_id_set_name (sid, "PCM");
+		elem = snd_mixer_find_selem (handle, sid);
+		if (!elem)
+		{
+			D("snd_mixer_find_selem");
+			goto bail;
+		}
+	}
+
+	if (!snd_mixer_selem_has_playback_volume (elem))
+	{
+		D("snd_mixer_selem_has_playback_volume");
+		goto bail;
+	}
+
+	snd_mixer_selem_get_playback_volume_range (elem,
+			&(self->_priv->pmin),
+			&(self->_priv->pmax));
+
+	self->_priv->has_mute = snd_mixer_selem_has_playback_switch (elem);
+	self->_priv->handle = handle;
+	self->_priv->elem = elem;
+
+	return TRUE;
+
+bail:
+	acme_volume_alsa_close_real (self);
+	return FALSE;
+}
+
+static void
+acme_volume_alsa_close (AcmeVolumeAlsa *self)
+{
+	self->_priv->timer_id = g_timeout_add (4000,
+			(GSourceFunc) acme_volume_alsa_close_real, self);
+}
+
+static void
+acme_volume_alsa_init (AcmeVolumeAlsa *self)
+{
+	self->_priv = g_new0 (AcmeVolumeAlsaPrivate, 1);
+
+	if (acme_volume_alsa_open (self) == FALSE)
+	{
+		g_free (self->_priv);
+		self->_priv = NULL;
+		return;
+	}
+
+	if (self->_priv->handle != NULL) {
+		acme_volume_alsa_close_real (self);
+		return;
+	}
+}
+
+static void
+acme_volume_alsa_class_init (AcmeVolumeAlsaClass *klass)
+{
+	AcmeVolumeClass *volume_class = ACME_VOLUME_CLASS (klass);
+	G_OBJECT_CLASS (klass)->finalize = acme_volume_alsa_finalize;
+
+	volume_class->set_volume = acme_volume_alsa_set_volume;
+	volume_class->get_volume = acme_volume_alsa_get_volume;
+	volume_class->set_mute = acme_volume_alsa_set_mute;
+	volume_class->get_mute = acme_volume_alsa_get_mute;
+	volume_class->get_threshold = acme_volume_alsa_get_threshold;
+}
+