Jack2 1.9.10

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 // When used in "slave" mode
00034 
00035 int JackLoopbackDriver::ProcessReadSync()
00036 {
00037     int res = 0;
00038 
00039     // Loopback copy
00040     for (int i = 0; i < fCaptureChannels; i++) {
00041         memcpy(GetInputBuffer(i), GetOutputBuffer(i), sizeof(jack_default_audio_sample_t) * fEngineControl->fBufferSize);
00042     }
00043 
00044     // Resume connected clients in the graph
00045     if (ResumeRefNum() < 0) {
00046         jack_error("JackLoopbackDriver::ProcessReadSync - ResumeRefNum error");
00047         res = -1;
00048     }
00049 
00050     return res;
00051 }
00052 
00053 int JackLoopbackDriver::ProcessWriteSync()
00054 {
00055     // Suspend on connected clients in the graph
00056     if (SuspendRefNum() < 0) {
00057         jack_error("JackLoopbackDriver::ProcessWriteSync - SuspendRefNum error");
00058         return -1;
00059     }
00060     return 0;
00061 }
00062 
00063 int JackLoopbackDriver::ProcessReadAsync()
00064 {
00065     int res = 0;
00066 
00067     // Loopback copy
00068     for (int i = 0; i < fCaptureChannels; i++) {
00069         memcpy(GetInputBuffer(i), GetOutputBuffer(i), sizeof(jack_default_audio_sample_t) * fEngineControl->fBufferSize);
00070     }
00071 
00072     // Resume connected clients in the graph
00073     if (ResumeRefNum() < 0) {
00074         jack_error("JackLoopbackDriver::ProcessReadAsync - ResumeRefNum error");
00075         res = -1;
00076     }
00077 
00078     return res;
00079 }
00080 
00081 int JackLoopbackDriver::ProcessWriteAsync()
00082 {
00083     return 0;
00084 }
00085 
00086 } // end of namespace
00087 
00088 #ifdef __cplusplus
00089 extern "C"
00090 {
00091 #endif
00092 
00093     SERVER_EXPORT jack_driver_desc_t * driver_get_descriptor()
00094     {
00095         jack_driver_desc_t * desc;
00096         jack_driver_desc_filler_t filler;
00097         jack_driver_param_value_t value;
00098 
00099         desc = jack_driver_descriptor_construct("loopback", JackDriverSlave, "Loopback backend", &filler);
00100 
00101         value.i = 0;
00102         jack_driver_descriptor_add_parameter(desc, &filler, "channels", 'c', JackDriverParamInt, &value, NULL, "Maximum number of loopback ports", NULL);
00103 
00104         return desc;
00105     }
00106 
00107     SERVER_EXPORT Jack::JackDriverClientInterface* driver_initialize(Jack::JackLockedEngine* engine, Jack::JackSynchro* table, const JSList* params)
00108     {
00109         const JSList * node;
00110         const jack_driver_param_t * param;
00111         int channels = 2;
00112 
00113         for (node = params; node; node = jack_slist_next (node)) {
00114             param = (const jack_driver_param_t *) node->data;
00115 
00116             switch (param->character) {
00117 
00118                 case 'c':
00119                     channels = param->value.ui;
00120                     break;
00121                 }
00122         }
00123 
00124         Jack::JackDriverClientInterface* driver = new Jack::JackLoopbackDriver(engine, table);
00125         if (driver->Open(0, 0, 1, 1, channels, channels, false, "loopback", "loopback", 0, 0) == 0) {
00126             return driver;
00127         } else {
00128             delete driver;
00129             return NULL;
00130         }
00131     }
00132 
00133 #ifdef __cplusplus
00134 }
00135 #endif