sintonia/library/ecasound-2.7.2/libecasound/audioio-db-buffer.cpp

122 lines
3.3 KiB
C++

// ------------------------------------------------------------------------
// audioio-db-buffer.cpp: Buffer used between db server and client
// Copyright (C) 2000-2002 Kai Vehmanen
//
// 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
// ------------------------------------------------------------------------
#include "samplebuffer.h"
#include "audioio-db-buffer.h"
/**
* Constructor.
*/
AUDIO_IO_DB_BUFFER::AUDIO_IO_DB_BUFFER(int number_of_buffers,
long int buffersize,
int channels)
: readptr_rep(0),
writeptr_rep(0),
finished_rep(0),
sbufs_rep(number_of_buffers)
{
for(size_t n = 0; n < sbufs_rep.size(); n++) {
sbufs_rep[n] = new SAMPLE_BUFFER(buffersize, channels);
}
// std::cerr << "Created a new client buffer with " << sbufs_rep.size() << " buffers." << std::endl;
}
AUDIO_IO_DB_BUFFER::~AUDIO_IO_DB_BUFFER(void)
{
for(size_t n = 0; n < sbufs_rep.size(); n++) {
delete sbufs_rep[n];
}
}
/**
* Resets all pointers to their initial state.
*/
void AUDIO_IO_DB_BUFFER::reset(void)
{
readptr_rep.set(0);
writeptr_rep.set(0);
finished_rep.set(0);
}
/**
* Number of sample buffer available for reading.
*
* Note! As concurrent access is allowed by
* the implement, the actual number of
* samples available for reading can
* be greater than that reported by
* read_space().
*/
int AUDIO_IO_DB_BUFFER::read_space(void)
{
int write = writeptr_rep.get();
int read = readptr_rep.get();
if (write >= read)
return(write - read);
else
return((write - read + sbufs_rep.size()) % sbufs_rep.size());
}
/**
* Number of sample buffers available for writing.
*
* Note! As concurrent access is allowed by
* the implement, the actual number of
* samples available for writing can
* be greater than that reported by
* write_space().
*/
int AUDIO_IO_DB_BUFFER::write_space(void)
{
int write = writeptr_rep.get();
int read = readptr_rep.get();
if (write > read)
return(((read - write + sbufs_rep.size()) % sbufs_rep.size()) - 1);
else if (write < read)
return(read - write - 1);
else
return(sbufs_rep.size() - 1);
}
/**
* Increment the read pointer by one.
*
* Note! Cannot be called from multiple concurrent
* execution contexts.
**/
void AUDIO_IO_DB_BUFFER::advance_read_pointer(void)
{
readptr_rep.set((readptr_rep.get() + 1) % sbufs_rep.size());
}
/**
* Increment the write pointer by one.
*
* Note! Cannot be called from multiple concurrent
* execution contexts.
**/
void AUDIO_IO_DB_BUFFER::advance_write_pointer(void)
{
writeptr_rep.set((writeptr_rep.get() + 1) % sbufs_rep.size());
}