Jack2 1.9.6

JackLoopbackDriver.cpp

00001 /*
00002 Copyright (C) 2001 Paul Davis
00003 Copyright (C) 2004-2008 Grame
00004 
00005 This program is free software; you can redistribute it and/or modify
00006 it under the terms of the GNU General Public License as published by
00007 the Free Software Foundation; either version 2 of the License, or
00008 (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., 675 Mass Ave, Cambridge, MA 02139, USA.
00018 
00019 */
00020 
00021 #include "JackSystemDeps.h"
00022 #include "JackLoopbackDriver.h"
00023 #include "JackDriverLoader.h"
00024 #include "JackEngineControl.h"
00025 #include "JackGraphManager.h"
00026 #include "JackError.h"
00027 #include <iostream>
00028 #include <assert.h>
00029 
00030 namespace Jack
00031 {
00032 
00033 int JackLoopbackDriver::Process()
00034 {
00035     // Loopback copy
00036     for (int i = 0; i < fCaptureChannels; i++) {
00037         memcpy(GetInputBuffer(i), GetOutputBuffer(i), sizeof(float) * fEngineControl->fBufferSize);
00038     }
00039 
00040     fGraphManager->ResumeRefNum(&fClientControl, fSynchroTable); // Signal all clients
00041     if (fEngineControl->fSyncMode) {
00042         if (fGraphManager->SuspendRefNum(&fClientControl, fSynchroTable, DRIVER_TIMEOUT_FACTOR * fEngineControl->fTimeOutUsecs) < 0) {
00043             jack_error("JackLoopbackDriver::ProcessSync SuspendRefNum error");
00044             return -1;
00045         }
00046     }
00047     return 0;
00048 }
00049 
00050 } // end of namespace
00051 
00052 #ifdef __cplusplus
00053 extern "C"
00054 {
00055 #endif
00056 
00057     SERVER_EXPORT jack_driver_desc_t * driver_get_descriptor() 
00058     {
00059         jack_driver_desc_t * desc;
00060         unsigned int i;
00061 
00062         desc = (jack_driver_desc_t*)calloc (1, sizeof (jack_driver_desc_t));
00063         strcpy(desc->name, "loopback");              // size MUST be less then JACK_DRIVER_NAME_MAX + 1
00064         strcpy(desc->desc, "Loopback backend");      // size MUST be less then JACK_DRIVER_PARAM_DESC + 1
00065 
00066         desc->nparams = 1;
00067         desc->params = (jack_driver_param_desc_t*)calloc (desc->nparams, sizeof (jack_driver_param_desc_t));
00068         
00069         i = 0;
00070         strcpy(desc->params[i].name, "channels");
00071         desc->params[i].character = 'c';
00072         desc->params[i].type = JackDriverParamInt;
00073         desc->params[i].value.ui = 0;
00074         strcpy(desc->params[i].short_desc, "Maximum number of loopback ports");
00075         strcpy(desc->params[i].long_desc, desc->params[i].short_desc);
00076 
00077         return desc;
00078     }
00079 
00080     SERVER_EXPORT Jack::JackDriverClientInterface* driver_initialize(Jack::JackLockedEngine* engine, Jack::JackSynchro* table, const JSList* params) 
00081     {
00082         const JSList * node;
00083         const jack_driver_param_t * param;
00084         int channels = 2;
00085       
00086         for (node = params; node; node = jack_slist_next (node)) {
00087             param = (const jack_driver_param_t *) node->data;
00088 
00089             switch (param->character) {
00090 
00091                 case 'c':
00092                     channels = param->value.ui;
00093                     break;
00094                 }
00095         }
00096         
00097         Jack::JackDriverClientInterface* driver = new Jack::JackLoopbackDriver(engine, table);
00098         if (driver->Open(1, 1, channels, channels, false, "loopback", "loopback", 0, 0) == 0) {
00099             return driver;
00100         } else {
00101             delete driver;
00102             return NULL;
00103         }
00104     }
00105 
00106 #ifdef __cplusplus
00107 }
00108 #endif