common/JackDummyDriver.cpp

   1 /*
   2 Copyright (C) 2001 Paul Davis
   3 Copyright (C) 2004-2008 Grame
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18
  19 */
  20
  21 #include "JackDummyDriver.h"
  22 #include "JackDriverLoader.h"
  23 #include "JackThreadedDriver.h"
  24 #include "JackCompilerDeps.h"
  25 #include <iostream>
  26 #include <unistd.h>
  27 #include <math.h>
  28
  29
  30 #ifdef __cplusplus
  31 extern "C"
  32 {
  33 #endif
  34
  35     SERVER_EXPORT jack_driver_desc_t * driver_get_descriptor () {
  36         jack_driver_desc_t * desc;
  37         jack_driver_desc_filler_t filler;
  38         jack_driver_param_value_t value;
  39
  40         desc = jack_driver_descriptor_construct("dummy", JackDriverMaster, "Timer based backend", &filler);
  41
  42         value.ui = 2U;
  43         jack_driver_descriptor_add_parameter(desc, &filler, "capture", 'C', JackDriverParamUInt, &value, NULL, "Number of capture ports", NULL);
  44         jack_driver_descriptor_add_parameter(desc, &filler, "playback", 'P', JackDriverParamUInt, &value, NULL, "Number of playback ports", NULL);
  45
  46         value.ui = 48000U;
  47         jack_driver_descriptor_add_parameter(desc, &filler, "rate", 'r', JackDriverParamUInt, &value, NULL, "Sample rate", NULL);
  48
  49         value.i = 0;
  50         jack_driver_descriptor_add_parameter(desc, &filler, "monitor", 'm', JackDriverParamBool, &value, NULL, "Provide monitor ports for the output", NULL);
  51
  52         value.ui = 1024U;
  53         jack_driver_descriptor_add_parameter(desc, &filler, "period", 'p', JackDriverParamUInt, &value, NULL, "Frames per period", NULL);
  54
  55         value.ui = 21333U;
  56         jack_driver_descriptor_add_parameter(desc, &filler, "wait", 'w', JackDriverParamUInt, &value, NULL, "Number of usecs to wait between engine processes", NULL);
  57
  58         return desc;
  59     }
  60
  61     SERVER_EXPORT Jack::JackDriverClientInterface* driver_initialize(Jack::JackLockedEngine* engine, Jack::JackSynchro* table, const JSList* params) {
  62         jack_nframes_t sample_rate = 48000;
  63         jack_nframes_t buffer_size = 1024;
  64         unsigned int capture_ports = 2;
  65         unsigned int playback_ports = 2;
  66         int wait_time = 0;
  67         const JSList * node;
  68         const jack_driver_param_t * param;
  69         bool monitor = false;
  70
  71         for (node = params; node; node = jack_slist_next (node)) {
  72             param = (const jack_driver_param_t *) node->data;
  73
  74             switch (param->character) {
  75
  76                 case 'C':
  77                     capture_ports = param->value.ui;
  78                     break;
  79
  80                 case 'P':
  81                     playback_ports = param->value.ui;
  82                     break;
  83
  84                 case 'r':
  85                     sample_rate = param->value.ui;
  86                     break;
  87
  88                 case 'p':
  89                     buffer_size = param->value.ui;
  90                     break;
  91
  92                 case 'w':
  93                     wait_time = param->value.ui;
  94                     break;
  95
  96                 case 'm':
  97                     monitor = param->value.i;
  98                     break;
  99             }
 100         }
 101
 102         if (wait_time > 0) {
 103             buffer_size = lroundf((float(wait_time) * float(sample_rate)) / 1000000.0f);
 104         }
 105
 106         if (buffer_size > BUFFER_SIZE_MAX) {
 107             buffer_size = BUFFER_SIZE_MAX;
 108             jack_error("Buffer size set to %d", BUFFER_SIZE_MAX);
 109         }
 110
 111         Jack::JackDriverClientInterface* driver = new Jack::JackThreadedDriver(new Jack::JackDummyDriver("system", "dummy_pcm", engine, table));
 112         if (driver->Open(buffer_size, sample_rate, 1, 1, capture_ports, playback_ports, monitor, "dummy", "dummy", 0, 0) == 0) {
 113             return driver;
 114         } else {
 115             delete driver;
 116             return NULL;
 117         }
 118     }
 119
 120 #ifdef __cplusplus
 121 }
 122 #endif