/*------------------------------------------------------------------------------
Copyright (c) 2004
LS Informationstechnik (LIKE)
University of Erlangen Nuremberg
All rights reserved.
Tyrell DarkIce
File : AlsaDspSource.h
Version : $Revision: 1.1 $
Author : $Author: darkeye $
Location : $Source: /cvsroot/darkice/darkice/src/AlsaDspSource.h,v $
Copyright notice:
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 02111-1307, USA.
------------------------------------------------------------------------------*/
#ifndef ALSA_SOURCE_H
#define ALSA_SOURCE_H
#ifndef __cplusplus
#error This is a C++ include file
#endif
/* ============================================================ include files */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "Reporter.h"
#include "AudioSource.h"
#ifdef HAVE_ALSA_LIB
#include
#else
#error configure for ALSA
#endif
/* ================================================================ constants */
/* =================================================================== macros */
/* =============================================================== data types */
/**
* An audio input based on the ALSA sound system
*
* @author $Author: darkeye $
* @version $Revision: 1.1 $
*/
class AlsaDspSource : public AudioSource, public virtual Reporter
{
private:
/**
* Name of the capture PCM stream.
*/
char *pcmName;
/**
* Handle to access PCM stream data.
*/
snd_pcm_t *captureHandle;
/**
* Stores number of bytes per frame. One frame
* contains all samples per time instance.
*/
int bytesPerFrame;
/**
* Is the stream running?
*/
bool running;
/**
* Number of useconds to do buffering in the audio device.
*/
unsigned int bufferTime;
protected:
/**
* Default constructor. Always throws an Exception.
*
* @exception Exception
*/
inline
AlsaDspSource ( void ) throw ( Exception )
{
throw Exception( __FILE__, __LINE__);
}
/**
* Initialize the object
*
* @param name the PCM to open.
* @exception Exception
*/
void
init ( const char * name ) throw ( Exception );
/**
* De-iitialize the object
*
* @exception Exception
*/
void
strip ( void ) throw ( Exception );
public:
/**
* Constructor.
*
* @param name the PCM (e.g. "hwplug:0,0").
* @param sampleRate samples per second (e.g. 44100 for 44.1kHz).
* @param bitsPerSample bits per sample (e.g. 16 bits).
* @param channel number of channels of the audio source
* (e.g. 1 for mono, 2 for stereo, etc.).
* @exception Exception
*/
inline
AlsaDspSource ( const char * name,
int sampleRate = 44100,
int bitsPerSample = 16,
int channel = 2 )
throw ( Exception )
: AudioSource( sampleRate, bitsPerSample, channel)
{
init( name);
}
/**
* Copy Constructor.
*
* @param source the object to copy.
* @exception Exception
*/
inline
AlsaDspSource ( const AlsaDspSource & ds ) throw ( Exception )
: AudioSource( ds )
{
init( ds.pcmName);
}
/**
* Destructor.
*
* @exception Exception
*/
inline virtual
~AlsaDspSource ( void ) throw ( Exception )
{
strip();
}
/**
* Assignment operator.
*
* @param ds the object to assign to this one.
* @return a reference to this object.
* @exception Exception
*/
inline virtual AlsaDspSource &
operator= ( const AlsaDspSource & ds ) throw ( Exception )
{
if ( this != &ds ) {
strip();
AudioSource::operator=( ds);
init( ds.pcmName);
}
return *this;
}
/**
* Tell if the data from this source comes in big or little endian.
*
* @return true if the source is big endian, false otherwise
*/
virtual bool
isBigEndian ( void ) const throw ();
/**
* Open the AlsaDspSource.
* This does not put Alsa device into recording mode.
* To start getting samples, call either canRead() or read().
*
* @return true if opening was successful, false otherwise
* @exception Exception
*
* @see #canRead
* @see #read
*/
virtual bool
open ( void ) throw ( Exception );
/**
* Check if the AlsaDspSource is open.
*
* @return true if the AlsaDspSource is open, false otherwise.
*/
inline virtual bool
isOpen ( void ) const throw ()
{
return captureHandle != 0;
}
/**
* Check if the AlsaDspSource can be read from.
* Blocks until the specified time for data to be available.
* Puts the PCM into recording mode.
*
* @param sec the maximum seconds to block.
* @param usec micro seconds to block after the full seconds.
* @return true if the AlsaDspSource is ready to be read from,
* false otherwise.
* @exception Exception
*/
virtual bool
canRead ( unsigned int sec,
unsigned int usec ) throw ( Exception );
/**
* Read from the AlsaDspSource.
* Puts the PCM into recording mode.
*
* @param buf the buffer to read into.
* @param len the number of bytes to read into buf
* @return the number of bytes read (may be less than len).
* @exception Exception
*/
virtual unsigned int
read ( void * buf,
unsigned int len ) throw ( Exception );
/**
* Close the AlsaDspSource.
*
* @exception Exception
*/
virtual void
close ( void ) throw ( Exception );
/**
* Returns the buffer size in useconds.
*
* @return the number of useconds audio will be buffered in ALSA
*/
inline virtual unsigned int
getBufferTime( void ) const
{
return bufferTime;
}
/**
* Sets the number of useconds to buffer audio in ALSA
*
* @param time buffer time
*/
inline virtual void
setBufferTime( unsigned int time ) {
bufferTime = time;
}
};
/* ================================================= external data structures */
/* ====================================================== function prototypes */
#endif /* ALSA_SOURCE_H */
/*------------------------------------------------------------------------------
$Source: /cvsroot/darkice/darkice/src/AlsaDspSource.h,v $
$Log: AlsaDspSource.h,v $
Revision 1.1 2004/02/15 12:06:29 darkeye
added ALSA support, thanks to Christian Forster
------------------------------------------------------------------------------*/
| Generated by: darkeye on destroy on Sun Feb 15 23:41:12 2004, using kdoc 2.0a54. |