Jack2  1.9.9
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;
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((wait_time * sample_rate) / 1000000.0f);
104  if (buffer_size > BUFFER_SIZE_MAX) {
105  buffer_size = BUFFER_SIZE_MAX;
106  jack_error("Buffer size set to %d", BUFFER_SIZE_MAX);
107  }
108  }
109 
110  Jack::JackDriverClientInterface* driver = new Jack::JackThreadedDriver(new Jack::JackDummyDriver("system", "dummy_pcm", engine, table));
111  if (driver->Open(buffer_size, sample_rate, 1, 1, capture_ports, playback_ports, monitor, "dummy", "dummy", 0, 0) == 0) {
112  return driver;
113  } else {
114  delete driver;
115  return NULL;
116  }
117  }
118 
119 #ifdef __cplusplus
120 }
121 #endif
The base class for threaded drivers using a &quot;decorator&quot; pattern. Threaded drivers are used with block...
Inter process synchronization using using Mach semaphore.
Locked Engine, access to methods is serialized using a mutex.
SERVER_EXPORT void jack_error(const char *fmt,...)
Definition: JackError.cpp:91
The dummy driver.
The base interface for drivers clients.
Definition: JackDriver.h:122