MythTV: audioinputalsa.h Source File

00001 /*
00002  * Copyright (C) 2007  Anand K. Mistry
00003  * Copyright (C) 2008  Alan Calvert
00004  *
00005  * This program is free software; you can redistribute it and/or
00006  * modify it under the terms of the GNU General Public License
00007  * as published by the Free Software Foundation; either version 2
00008  * of the License, or (at your option) any later version.
00009  *
00010  * This program is distributed in the hope that it will be useful,
00011  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00012  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00013  * GNU General Public License for more details.
00014  *
00015  * You should have received a copy of the GNU General Public License
00016  * along with this program; if not, write to the Free Software
00017  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
00018  * 02110-1301, USA.
00019  */
00020 
00021 #ifndef _AUDIOINPUTALSA_H_
00022 #define _AUDIOINPUTALSA_H_
00023 
00024 #include "audioinput.h"
00025 
00026 #ifdef USING_ALSA
00027 #include <alsa/asoundlib.h>
00028 #else
00029 typedef int snd_pcm_t;
00030 typedef int snd_pcm_uframes_t;
00031 #endif // USING_ALSA
00032 
00033 class AudioInputALSA : public AudioInput
00034 {
00035   public:
00036     AudioInputALSA(const QString &device);
00037     ~AudioInputALSA() { Close(); };
00038 
00039     bool Open(uint sample_bits, uint sample_rate, uint channels);
00040     inline bool IsOpen(void) { return (pcm_handle != NULL); }
00041     void Close(void);
00042 
00043     bool Start(void) { return (pcm_handle != NULL); }
00044     bool Stop(void);
00045 
00046     inline int GetBlockSize(void) { return myth_block_bytes; };
00047     int GetSamples(void* buf, uint nbytes);
00048     int GetNumReadyBytes(void);
00049 
00050   private:
00051     bool PrepHwParams(void);
00052     bool PrepSwParams(void);
00053     int  PcmRead(void* buf, uint nbytes);
00054     bool Recovery(int err);
00055     bool AlsaBad(int op_result, QString errmsg);
00056 
00057     QByteArray          alsa_device;
00058     snd_pcm_t*          pcm_handle;
00059     snd_pcm_uframes_t   period_size;
00060     int                 myth_block_bytes;
00061 };
00062 #endif /* _AUDIOINPUTALSA_H_ */
00063 /* vim: set expandtab tabstop=4 shiftwidth=4: */
00064