/* * Control Interface - main file * Copyright (c) 1998 by Jaroslav Kysela * * * 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 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 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., 675 Mass Ave, Cambridge, MA 02139, USA. * */ #include #include #include #include #include #include #include #include "asoundlib.h" #define SND_FILE_CONTROL "/dev/snd/control%i" int snd_cards( void ) { int idx, count; unsigned int mask; mask = snd_cards_mask(); for ( idx = 0, count = 0; idx < SND_CARDS; idx++ ) { if ( mask & (1 << idx) ) count++; } return count; } /* * this routine uses very ugly method... * need to do... */ unsigned int snd_cards_mask( void ) { int fd, idx; unsigned int mask; char filename[32]; for ( idx = 0, mask = 0; idx < SND_CARDS; idx++ ) { sprintf( filename, SND_FILE_CONTROL, idx ); if ( (fd = open( filename, O_RDWR )) < 0 ) continue; close( fd ); mask |= 1 << idx; } return mask; } int snd_card_name( const char *string ) { int card, cards; void *handle; struct snd_ctl_hw_info info; cards = snd_cards(); if ( cards <= 0 ) return -ENODEV; if ( !string ) return -EINVAL; if ( (isdigit( *string ) && *(string+1) == 0) || (isdigit( *string ) && isdigit( *(string+1) ) && *(string+2) == 0) ) { sscanf( string, "%i", &card ); card--; if ( card < 0 || card >= cards ) return -EINVAL; return card; } for ( card = 0; card < cards; card++ ) { if ( snd_ctl_open( &handle, card ) < 0 ) continue; if ( snd_ctl_hw_info( handle, &info ) < 0 ) { snd_ctl_close( handle ); continue; } snd_ctl_close( handle ); if ( !strcmp( info.id, string ) ) return card; } return -ENODEV; }