intf.c

video linux conference

/*****************************************************************************
 * intf.c : audio output API towards the interface modules
 *****************************************************************************
 * Copyright (C) 2002-2004 VideoLAN
 * $Id: intf.c 10408 2005-03-22 20:17:30Z jpsaman $
 *
 * Authors: Christophe Massiot <[e-mail]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
#include <stdlib.h>                            /* calloc(), malloc(), free() */
#include <string.h>

#include <vlc/vlc.h>

#include "audio_output.h"
#include "aout_internal.h"


/*
 * Volume management
 *
 * The hardware volume cannot be set if the output module gets deleted, so
 * we must take the mixer lock. The software volume cannot be set while the
 * mixer is running, so we need the mixer lock (too).
 *
 * Here is a schematic of the i_volume range :
 *
 * |------------------------------+---------------------------------------|
 * 0                           pi_soft                                   1024
 *
 * Between 0 and pi_soft, the volume is done in hardware by the output
 * module. Above, the output module will change p_aout->mixer.i_multiplier
 * (done in software). This scaling may result * in cropping errors and
 * should be avoided as much as possible.
 *
 * It is legal to have *pi_soft == 0, and do everything in software.
 * It is also legal to have *pi_soft == 1024, and completely avoid
 * software scaling. However, some streams (esp. A/52) are encoded with
 * a very low volume and users may complain.
 */

/*****************************************************************************
 * aout_VolumeGet : get the volume of the output device
 *****************************************************************************/
int __aout_VolumeGet( vlc_object_t * p_object, audio_volume_t * pi_volume )
{
    int i_volume, i_result = 0;
    aout_instance_t * p_aout = vlc_object_find( p_object, VLC_OBJECT_AOUT,
                                                FIND_ANYWHERE );

    i_volume = config_GetInt( p_object, "volume" );
    if ( pi_volume != NULL ) *pi_volume = (audio_volume_t)i_volume;

    if ( p_aout == NULL ) return 0;

    vlc_mutex_lock( &p_aout->mixer_lock );
    if ( !p_aout->mixer.b_error )
    {
        i_result = p_aout->output.pf_volume_get( p_aout, pi_volume );
    }
    vlc_mutex_unlock( &p_aout->mixer_lock );

    vlc_object_release( p_aout );
    return i_result;
}

/*****************************************************************************
 * aout_VolumeSet : set the volume of the output device
 *****************************************************************************/
int __aout_VolumeSet( vlc_object_t * p_object, audio_volume_t i_volume )
{
    vlc_value_t val;
    aout_instance_t * p_aout = vlc_object_find( p_object, VLC_OBJECT_AOUT,
                                                FIND_ANYWHERE );
    int i_result = 0;

    config_PutInt( p_object, "volume", i_volume );

    if ( p_aout == NULL ) return 0;

    vlc_mutex_lock( &p_aout->mixer_lock );
    if ( !p_aout->mixer.b_error )
    {
        i_result = p_aout->output.pf_volume_set( p_aout, i_volume );
    }
    vlc_mutex_unlock( &p_aout->mixer_lock );

    vlc_object_release( p_aout );

    val.b_bool = VLC_TRUE;
    var_Set( p_aout, "intf-change", val );
    return i_result;
}

/*****************************************************************************
 * aout_VolumeInfos : get the boundary pi_soft
 *****************************************************************************/
int __aout_VolumeInfos( vlc_object_t * p_object, audio_volume_t * pi_soft )
{
    aout_instance_t * p_aout = vlc_object_find( p_object, VLC_OBJECT_AOUT,
                                                FIND_ANYWHERE );
    int i_result;

    if ( p_aout == NULL ) return 0;

    vlc_mutex_lock( &p_aout->mixer_lock );
    if ( p_aout->mixer.b_error )
    {
        /* The output module is destroyed. */
        i_result = -1;
    }
    else
    {
        i_result = p_aout->output.pf_volume_infos( p_aout, pi_soft );
    }
    vlc_mutex_unlock( &p_aout->mixer_lock );

    vlc_object_release( p_aout );
    return i_result;
}

/*****************************************************************************
 * aout_VolumeUp : raise the output volume
 *****************************************************************************
 * If pi_volume != NULL, *pi_volume will contain the volume at the end of the
 * function.
 *****************************************************************************/
int __aout_VolumeUp( vlc_object_t * p_object, int i_nb_steps,
                   audio_volume_t * pi_volume )
{
    aout_instance_t * p_aout = vlc_object_find( p_object, VLC_OBJECT_AOUT,
                                                FIND_ANYWHERE );
    int i_result = 0, i_volume = 0;

    i_volume = config_GetInt( p_object, "volume" );
    i_volume += AOUT_VOLUME_STEP * i_nb_steps;
    if ( i_volume > AOUT_VOLUME_MAX )
    {
        i_volume = AOUT_VOLUME_MAX;
    }
    config_PutInt( p_object, "volume", i_volume );
    var_Create( p_object->p_libvlc, "saved-volume", VLC_VAR_INTEGER );
    var_SetInteger( p_object->p_libvlc, "saved-volume" , (audio_volume_t) i_volume );
    if ( pi_volume != NULL ) *pi_volume = (audio_volume_t) i_volume;

    if ( p_aout == NULL ) return 0;

    vlc_mutex_lock( &p_aout->mixer_lock );
    if ( !p_aout->mixer.b_error )
    {
        i_result = p_aout->output.pf_volume_set( p_aout, (audio_volume_t) i_volume );
    }
    vlc_mutex_unlock( &p_aout->mixer_lock );

    vlc_object_release( p_aout );
    return i_result;
}

/*****************************************************************************
 * aout_VolumeDown : lower the output volume
 *****************************************************************************
 * If pi_volume != NULL, *pi_volume will contain the volume at the end of the
 * function.
 *****************************************************************************/
int __aout_VolumeDown( vlc_object_t * p_object, int i_nb_steps,
                     audio_volume_t * pi_volume )
{
    aout_instance_t * p_aout = vlc_object_find( p_object, VLC_OBJECT_AOUT,
                                                FIND_ANYWHERE );
    int i_result = 0, i_volume = 0;

    i_volume = config_GetInt( p_object, "volume" );
    i_volume -= AOUT_VOLUME_STEP * i_nb_steps;
    if ( i_volume < AOUT_VOLUME_MIN )
    {
        i_volume = AOUT_VOLUME_MIN;
    }
    config_PutInt( p_object, "volume", i_volume );
    var_Create( p_object->p_libvlc, "saved-volume", VLC_VAR_INTEGER );
    var_SetInteger( p_object->p_libvlc, "saved-volume", (audio_volume_t) i_volume );
    if ( pi_volume != NULL ) *pi_volume = (audio_volume_t) i_volume;

    if ( p_aout == NULL ) return 0;

    vlc_mutex_lock( &p_aout->mixer_lock );
    if ( !p_aout->mixer.b_error )
    {
        i_result = p_aout->output.pf_volume_set( p_aout, (audio_volume_t) i_volume );
    }
    vlc_mutex_unlock( &p_aout->mixer_lock );

    vlc_object_release( p_aout );
    return i_result;
}

/*****************************************************************************
 * aout_VolumeMute : Mute/un-mute the output volume
 *****************************************************************************
 * If pi_volume != NULL, *pi_volume will contain the volume at the end of the
 * function (muted => 0).
 *****************************************************************************/
int __aout_VolumeMute( vlc_object_t * p_object, audio_volume_t * pi_volume )
{
    int i_result;
    audio_volume_t i_volume;

    i_volume = (audio_volume_t)config_GetInt( p_object, "volume" );
    if ( i_volume != 0 )
    {
        /* Mute */