JackLoopbackDriver.cpp
/*
Copyright (C) 2001 Paul Davis
Copyright (C) 2004-2008 Grame
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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "JackSystemDeps.h"
#include "JackLoopbackDriver.h"
#include "JackDriverLoader.h"
#include "JackEngineControl.h"
#include "JackGraphManager.h"
#include "JackError.h"
#include <iostream>
#include <assert.h>
namespace Jack
{
// When used in "slave" mode
int JackLoopbackDriver::ProcessReadSync()
{
int res = 0;
// Loopback copy
for (int i = 0; i < fCaptureChannels; i++) {
memcpy(GetInputBuffer(i), GetOutputBuffer(i), sizeof(jack_default_audio_sample_t) * fEngineControl->fBufferSize);
}
// Resume connected clients in the graph
if (ResumeRefNum() < 0) {
jack_error("JackLoopbackDriver::ProcessReadSync - ResumeRefNum error");
res = -1;
}
return res;
}
int JackLoopbackDriver::ProcessWriteSync()
{
// Suspend on connected clients in the graph
if (SuspendRefNum() < 0) {
jack_error("JackLoopbackDriver::ProcessWriteSync - SuspendRefNum error");
return -1;
}
return 0;
}
int JackLoopbackDriver::ProcessReadAsync()
{
int res = 0;
// Loopback copy
for (int i = 0; i < fCaptureChannels; i++) {
memcpy(GetInputBuffer(i), GetOutputBuffer(i), sizeof(jack_default_audio_sample_t) * fEngineControl->fBufferSize);
}
// Resume connected clients in the graph
if (ResumeRefNum() < 0) {
jack_error("JackLoopbackDriver::ProcessReadAsync - ResumeRefNum error");
res = -1;
}
return res;
}
int JackLoopbackDriver::ProcessWriteAsync()
{
return 0;
}
} // end of namespace
#ifdef __cplusplus
extern "C"
{
#endif
SERVER_EXPORT jack_driver_desc_t * driver_get_descriptor()
{
jack_driver_desc_t * desc;
jack_driver_desc_filler_t filler;
jack_driver_param_value_t value;
desc = jack_driver_descriptor_construct("loopback", JackDriverSlave, "Loopback backend", &filler);
value.i = 0;
jack_driver_descriptor_add_parameter(desc, &filler, "channels", 'c', JackDriverParamInt, &value, NULL, "Maximum number of loopback ports", NULL);
return desc;
}
SERVER_EXPORT Jack::JackDriverClientInterface* driver_initialize(Jack::JackLockedEngine* engine, Jack::JackSynchro* table, const JSList* params)
{
const JSList * node;
const jack_driver_param_t * param;
int channels = 2;
for (node = params; node; node = jack_slist_next (node)) {
param = (const jack_driver_param_t *) node->data;
switch (param->character) {
case 'c':
channels = param->value.ui;
break;
}
}
Jack::JackDriverClientInterface* driver = new Jack::JackLoopbackDriver(engine, table);
if (driver->Open(0, 0, 1, 1, channels, channels, false, "loopback", "loopback", 0, 0) == 0) {
return driver;
} else {
delete driver;
return NULL;
}
}
#ifdef __cplusplus
}
#endif
Jack
Definition: JackAC3Encoder.cpp:30
Jack::JackLockedEngine
Locked Engine, access to methods is serialized using a mutex.
Definition: JackLockedEngine.h:78
jack_driver_param_value_t
Definition: driver_interface.h:64
Jack::JackPosixSemaphore
Inter process synchronization using POSIX semaphore.
Definition: JackPosixSemaphore.h:36
jack_error
SERVER_EXPORT void jack_error(const char *fmt,...)
Definition: JackError.cpp:92
jack_driver_desc_filler_t
Definition: driver_interface.h:142
Jack::JackDriverClientInterface
The base interface for drivers clients.
Definition: JackDriver.h:114
Jack::JackLoopbackDriver
The loopback driver : to be used to "pipeline" applications connected in sequence.
Definition: JackLoopbackDriver.h:33
jack_driver_param_t
Definition: driver_interface.h:125
_JSList
Definition: linux/alsa/jslist.h:35
jack_driver_desc_t
Definition: driver_interface.h:132