1 /************************************************************************/
2 /*! \class RtAudio
3 \brief Realtime audio i/o C++ classes.
4
5 RtAudio provides a common API (Application Programming Interface)
6 for realtime audio input/output across Linux (native ALSA, Jack,
7 and OSS), Macintosh OS X (CoreAudio and Jack), and Windows
8 (DirectSound, ASIO and WASAPI) operating systems.
9
10 RtAudio WWW site: http://www.music.mcgill.ca/~gary/rtaudio/
11
12 RtAudio: realtime audio i/o C++ classes
13 Copyright (c) 2001-2017 Gary P. Scavone
14
15 Permission is hereby granted, free of charge, to any person
16 obtaining a copy of this software and associated documentation files
17 (the "Software"), to deal in the Software without restriction,
18 including without limitation the rights to use, copy, modify, merge,
19 publish, distribute, sublicense, and/or sell copies of the Software,
20 and to permit persons to whom the Software is furnished to do so,
21 subject to the following conditions:
22
23 The above copyright notice and this permission notice shall be
24 included in all copies or substantial portions of the Software.
25
26 Any person wishing to distribute modifications to the Software is
27 asked to send the modifications to the original developer so that
28 they can be incorporated into the canonical version. This is,
29 however, not a binding provision of this license.
30
31 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
34 IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
35 ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
36 CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
38 */
39 /************************************************************************/
40
41 /*!
42 \file RtAudio.h
43 */
44
45 #ifndef __RTAUDIO_H
46 #define __RTAUDIO_H
47
48 #define RTAUDIO_VERSION "5.0.0"
49
50 #if defined _WIN32 || defined __CYGWIN__
51 #define RTAUDIO_DLL_PUBLIC
52 #else
53 #if __GNUC__ >= 4
54 #define RTAUDIO_DLL_PUBLIC __attribute__( (visibility( "default" )) )
55 #else
56 #define RTAUDIO_DLL_PUBLIC
57 #endif
58 #endif
59
60 #include <string>
61 #include <vector>
62 #include <stdexcept>
63 #include <iostream>
64
65 /*! \typedef typedef unsigned long RtAudioFormat;
66 \brief RtAudio data format type.
67
68 Support for signed integers and floats. Audio data fed to/from an
69 RtAudio stream is assumed to ALWAYS be in host byte order. The
70 internal routines will automatically take care of any necessary
71 byte-swapping between the host format and the soundcard. Thus,
72 endian-ness is not a concern in the following format definitions.
73
74 - \e RTAUDIO_SINT8: 8-bit signed integer.
75 - \e RTAUDIO_SINT16: 16-bit signed integer.
76 - \e RTAUDIO_SINT24: 24-bit signed integer.
77 - \e RTAUDIO_SINT32: 32-bit signed integer.
78 - \e RTAUDIO_FLOAT32: Normalized between plus/minus 1.0.
79 - \e RTAUDIO_FLOAT64: Normalized between plus/minus 1.0.
80 */
81 typedef unsigned long RtAudioFormat;
82 static const RtAudioFormat RTAUDIO_SINT8 = 0x1; // 8-bit signed integer.
83 static const RtAudioFormat RTAUDIO_SINT16 = 0x2; // 16-bit signed integer.
84 static const RtAudioFormat RTAUDIO_SINT24 = 0x4; // 24-bit signed integer.
85 static const RtAudioFormat RTAUDIO_SINT32 = 0x8; // 32-bit signed integer.
86 static const RtAudioFormat RTAUDIO_FLOAT32 = 0x10; // Normalized between plus/minus 1.0.
87 static const RtAudioFormat RTAUDIO_FLOAT64 = 0x20; // Normalized between plus/minus 1.0.
88
89 /*! \typedef typedef unsigned long RtAudioStreamFlags;
90 \brief RtAudio stream option flags.
91
92 The following flags can be OR'ed together to allow a client to
93 make changes to the default stream behavior:
94
95 - \e RTAUDIO_NONINTERLEAVED: Use non-interleaved buffers (default = interleaved).
96 - \e RTAUDIO_MINIMIZE_LATENCY: Attempt to set stream parameters for lowest possible latency.
97 - \e RTAUDIO_HOG_DEVICE: Attempt grab device for exclusive use.
98 - \e RTAUDIO_ALSA_USE_DEFAULT: Use the "default" PCM device (ALSA only).
99 - \e RTAUDIO_JACK_DONT_CONNECT: Do not automatically connect ports (JACK only).
100
101 By default, RtAudio streams pass and receive audio data from the
102 client in an interleaved format. By passing the
103 RTAUDIO_NONINTERLEAVED flag to the openStream() function, audio
104 data will instead be presented in non-interleaved buffers. In
105 this case, each buffer argument in the RtAudioCallback function
106 will point to a single array of data, with \c nFrames samples for
107 each channel concatenated back-to-back. For example, the first
108 sample of data for the second channel would be located at index \c
109 nFrames (assuming the \c buffer pointer was recast to the correct
110 data type for the stream).
111
112 Certain audio APIs offer a number of parameters that influence the
113 I/O latency of a stream. By default, RtAudio will attempt to set
114 these parameters internally for robust (glitch-free) performance
115 (though some APIs, like Windows Direct Sound, make this difficult).
116 By passing the RTAUDIO_MINIMIZE_LATENCY flag to the openStream()
117 function, internal stream settings will be influenced in an attempt
118 to minimize stream latency, though possibly at the expense of stream
119 performance.
120
121 If the RTAUDIO_HOG_DEVICE flag is set, RtAudio will attempt to
122 open the input and/or output stream device(s) for exclusive use.
123 Note that this is not possible with all supported audio APIs.
124
125 If the RTAUDIO_SCHEDULE_REALTIME flag is set, RtAudio will attempt
126 to select realtime scheduling (round-robin) for the callback thread.
127
128 If the RTAUDIO_ALSA_USE_DEFAULT flag is set, RtAudio will attempt to
129 open the "default" PCM device when using the ALSA API. Note that this
130 will override any specified input or output device id.
131
132 If the RTAUDIO_JACK_DONT_CONNECT flag is set, RtAudio will not attempt
133 to automatically connect the ports of the client to the audio device.
134 */
135 typedef unsigned int RtAudioStreamFlags;
136 static const RtAudioStreamFlags RTAUDIO_NONINTERLEAVED = 0x1; // Use non-interleaved buffers (default = interleaved).
137 static const RtAudioStreamFlags RTAUDIO_MINIMIZE_LATENCY = 0x2; // Attempt to set stream parameters for lowest possible latency.
138 static const RtAudioStreamFlags RTAUDIO_HOG_DEVICE = 0x4; // Attempt grab device and prevent use by others.
139 static const RtAudioStreamFlags RTAUDIO_SCHEDULE_REALTIME = 0x8; // Try to select realtime scheduling for callback thread.
140 static const RtAudioStreamFlags RTAUDIO_ALSA_USE_DEFAULT = 0x10; // Use the "default" PCM device (ALSA only).
141 static const RtAudioStreamFlags RTAUDIO_JACK_DONT_CONNECT = 0x20; // Do not automatically connect ports (JACK only).
142
143 /*! \typedef typedef unsigned long RtAudioStreamStatus;
144 \brief RtAudio stream status (over- or underflow) flags.
145
146 Notification of a stream over- or underflow is indicated by a
147 non-zero stream \c status argument in the RtAudioCallback function.
148 The stream status can be one of the following two options,
149 depending on whether the stream is open for output and/or input:
150
151 - \e RTAUDIO_INPUT_OVERFLOW: Input data was discarded because of an overflow condition at the driver.
152 - \e RTAUDIO_OUTPUT_UNDERFLOW: The output buffer ran low, likely producing a break in the output sound.
153 */
154 typedef unsigned int RtAudioStreamStatus;
155 static const RtAudioStreamStatus RTAUDIO_INPUT_OVERFLOW = 0x1; // Input data was discarded because of an overflow condition at the driver.
156 static const RtAudioStreamStatus RTAUDIO_OUTPUT_UNDERFLOW = 0x2; // The output buffer ran low, likely causing a gap in the output sound.
157
158 //! RtAudio callback function prototype.
159 /*!
160 All RtAudio clients must create a function of type RtAudioCallback
161 to read and/or write data from/to the audio stream. When the
162 underlying audio system is ready for new input or output data, this
163 function will be invoked.
164
165 \param outputBuffer For output (or duplex) streams, the client
166 should write \c nFrames of audio sample frames into this
167 buffer. This argument should be recast to the datatype
168 specified when the stream was opened. For input-only
169 streams, this argument will be NULL.
170
171 \param inputBuffer For input (or duplex) streams, this buffer will
172 hold \c nFrames of input audio sample frames. This
173 argument should be recast to the datatype specified when the
174 stream was opened. For output-only streams, this argument
175 will be NULL.
176
177 \param nFrames The number of sample frames of input or output
178 data in the buffers. The actual buffer size in bytes is
179 dependent on the data type and number of channels in use.
180
181 \param streamTime The number of seconds that have elapsed since the
182 stream was started.
183
184 \param status If non-zero, this argument indicates a data overflow
185 or underflow condition for the stream. The particular
186 condition can be determined by comparison with the
187 RtAudioStreamStatus flags.
188
189 \param userData A pointer to optional data provided by the client
190 when opening the stream (default = NULL).
191
192 To continue normal stream operation, the RtAudioCallback function
193 should return a value of zero. To stop the stream and drain the
194 output buffer, the function should return a value of one. To abort
195 the stream immediately, the client should return a value of two.
196 */
197 typedef int (*RtAudioCallback)( void *outputBuffer, void *inputBuffer,
198 unsigned int nFrames,
199 double streamTime,
200 RtAudioStreamStatus status,
201 void *userData );
202
203 /************************************************************************/
204 /*! \class RtAudioError
205 \brief Exception handling class for RtAudio.
206
207 The RtAudioError class is quite simple but it does allow errors to be
208 "caught" by RtAudioError::Type. See the RtAudio documentation to know
209 which methods can throw an RtAudioError.
210 */
211 /************************************************************************/
212
213 class RTAUDIO_DLL_PUBLIC RtAudioError : public std::runtime_error
214 {
215 public:
216 //! Defined RtAudioError types.
217 enum Type {
218 WARNING, /*!< A non-critical error. */
219 DEBUG_WARNING, /*!< A non-critical error which might be useful for debugging. */
220 UNSPECIFIED, /*!< The default, unspecified error type. */
221 NO_DEVICES_FOUND, /*!< No devices found on system. */
222 INVALID_DEVICE, /*!< An invalid device ID was specified. */
223 MEMORY_ERROR, /*!< An error occured during memory allocation. */
224 INVALID_PARAMETER, /*!< An invalid parameter was specified to a function. */
225 INVALID_USE, /*!< The function was called incorrectly. */
226 DRIVER_ERROR, /*!< A system driver error occured. */
227 SYSTEM_ERROR, /*!< A system error occured. */
228 THREAD_ERROR /*!< A thread error occured. */
229 };
230
231 //! The constructor.
232 RtAudioError( const std::string& message,
233 Type type = RtAudioError::UNSPECIFIED )
runtime_error(message)234 : std::runtime_error(message), type_(type) {}
235
236 //! Prints thrown error message to stderr.
printMessage(void)237 virtual void printMessage( void ) const
238 { std::cerr << '\n' << what() << "\n\n"; }
239
240 //! Returns the thrown error message type.
getType(void)241 virtual const Type& getType(void) const { return type_; }
242
243 //! Returns the thrown error message string.
getMessage(void)244 virtual const std::string getMessage(void) const
245 { return std::string(what()); }
246
247 protected:
248 Type type_;
249 };
250
251 //! RtAudio error callback function prototype.
252 /*!
253 \param type Type of error.
254 \param errorText Error description.
255 */
256 typedef void (*RtAudioErrorCallback)( RtAudioError::Type type, const std::string &errorText );
257
258 // **************************************************************** //
259 //
260 // RtAudio class declaration.
261 //
262 // RtAudio is a "controller" used to select an available audio i/o
263 // interface. It presents a common API for the user to call but all
264 // functionality is implemented by the class RtApi and its
265 // subclasses. RtAudio creates an instance of an RtApi subclass
266 // based on the user's API choice. If no choice is made, RtAudio
267 // attempts to make a "logical" API selection.
268 //
269 // **************************************************************** //
270
271 class RtApi;
272
273 class RTAUDIO_DLL_PUBLIC RtAudio
274 {
275 public:
276
277 //! Audio API specifier arguments.
278 enum Api {
279 UNSPECIFIED, /*!< Search for a working compiled API. */
280 LINUX_ALSA, /*!< The Advanced Linux Sound Architecture API. */
281 LINUX_PULSE, /*!< The Linux PulseAudio API. */
282 LINUX_OSS, /*!< The Linux Open Sound System API. */
283 UNIX_JACK, /*!< The Jack Low-Latency Audio Server API. */
284 MACOSX_CORE, /*!< Macintosh OS-X Core Audio API. */
285 WINDOWS_WASAPI, /*!< The Microsoft WASAPI API. */
286 WINDOWS_ASIO, /*!< The Steinberg Audio Stream I/O API. */
287 WINDOWS_DS, /*!< The Microsoft Direct Sound API. */
288 RTAUDIO_DUMMY /*!< A compilable but non-functional API. */
289 };
290
291 //! The public device information structure for returning queried values.
292 struct DeviceInfo {
293 bool probed; /*!< true if the device capabilities were successfully probed. */
294 std::string name; /*!< Character string device identifier. */
295 unsigned int outputChannels; /*!< Maximum output channels supported by device. */
296 unsigned int inputChannels; /*!< Maximum input channels supported by device. */
297 unsigned int duplexChannels; /*!< Maximum simultaneous input/output channels supported by device. */
298 bool isDefaultOutput; /*!< true if this is the default output device. */
299 bool isDefaultInput; /*!< true if this is the default input device. */
300 std::vector<unsigned int> sampleRates; /*!< Supported sample rates (queried from list of standard rates). */
301 unsigned int preferredSampleRate; /*!< Preferred sample rate, eg. for WASAPI the system sample rate. */
302 RtAudioFormat nativeFormats; /*!< Bit mask of supported data formats. */
303
304 // Default constructor.
DeviceInfoDeviceInfo305 DeviceInfo()
306 :probed(false), outputChannels(0), inputChannels(0), duplexChannels(0),
307 isDefaultOutput(false), isDefaultInput(false), preferredSampleRate(0), nativeFormats(0) {}
308 };
309
310 //! The structure for specifying input or ouput stream parameters.
311 struct StreamParameters {
312 unsigned int deviceId; /*!< Device index (0 to getDeviceCount() - 1). */
313 unsigned int nChannels; /*!< Number of channels. */
314 unsigned int firstChannel; /*!< First channel index on device (default = 0). */
315
316 // Default constructor.
StreamParametersStreamParameters317 StreamParameters()
318 : deviceId(0), nChannels(0), firstChannel(0) {}
319 };
320
321 //! The structure for specifying stream options.
322 /*!
323 The following flags can be OR'ed together to allow a client to
324 make changes to the default stream behavior:
325
326 - \e RTAUDIO_NONINTERLEAVED: Use non-interleaved buffers (default = interleaved).
327 - \e RTAUDIO_MINIMIZE_LATENCY: Attempt to set stream parameters for lowest possible latency.
328 - \e RTAUDIO_HOG_DEVICE: Attempt grab device for exclusive use.
329 - \e RTAUDIO_SCHEDULE_REALTIME: Attempt to select realtime scheduling for callback thread.
330 - \e RTAUDIO_ALSA_USE_DEFAULT: Use the "default" PCM device (ALSA only).
331
332 By default, RtAudio streams pass and receive audio data from the
333 client in an interleaved format. By passing the
334 RTAUDIO_NONINTERLEAVED flag to the openStream() function, audio
335 data will instead be presented in non-interleaved buffers. In
336 this case, each buffer argument in the RtAudioCallback function
337 will point to a single array of data, with \c nFrames samples for
338 each channel concatenated back-to-back. For example, the first
339 sample of data for the second channel would be located at index \c
340 nFrames (assuming the \c buffer pointer was recast to the correct
341 data type for the stream).
342
343 Certain audio APIs offer a number of parameters that influence the
344 I/O latency of a stream. By default, RtAudio will attempt to set
345 these parameters internally for robust (glitch-free) performance
346 (though some APIs, like Windows Direct Sound, make this difficult).
347 By passing the RTAUDIO_MINIMIZE_LATENCY flag to the openStream()
348 function, internal stream settings will be influenced in an attempt
349 to minimize stream latency, though possibly at the expense of stream
350 performance.
351
352 If the RTAUDIO_HOG_DEVICE flag is set, RtAudio will attempt to
353 open the input and/or output stream device(s) for exclusive use.
354 Note that this is not possible with all supported audio APIs.
355
356 If the RTAUDIO_SCHEDULE_REALTIME flag is set, RtAudio will attempt
357 to select realtime scheduling (round-robin) for the callback thread.
358 The \c priority parameter will only be used if the RTAUDIO_SCHEDULE_REALTIME
359 flag is set. It defines the thread's realtime priority.
360
361 If the RTAUDIO_ALSA_USE_DEFAULT flag is set, RtAudio will attempt to
362 open the "default" PCM device when using the ALSA API. Note that this
363 will override any specified input or output device id.
364
365 The \c numberOfBuffers parameter can be used to control stream
366 latency in the Windows DirectSound, Linux OSS, and Linux Alsa APIs
367 only. A value of two is usually the smallest allowed. Larger
368 numbers can potentially result in more robust stream performance,
369 though likely at the cost of stream latency. The value set by the
370 user is replaced during execution of the RtAudio::openStream()
371 function by the value actually used by the system.
372
373 The \c streamName parameter can be used to set the client name
374 when using the Jack API. By default, the client name is set to
375 RtApiJack. However, if you wish to create multiple instances of
376 RtAudio with Jack, each instance must have a unique client name.
377 */
378 struct StreamOptions {
379 RtAudioStreamFlags flags; /*!< A bit-mask of stream flags (RTAUDIO_NONINTERLEAVED, RTAUDIO_MINIMIZE_LATENCY, RTAUDIO_HOG_DEVICE, RTAUDIO_ALSA_USE_DEFAULT). */
380 unsigned int numberOfBuffers; /*!< Number of stream buffers. */
381 std::string streamName; /*!< A stream name (currently used only in Jack). */
382 int priority; /*!< Scheduling priority of callback thread (only used with flag RTAUDIO_SCHEDULE_REALTIME). */
383
384 // Default constructor.
StreamOptionsStreamOptions385 StreamOptions()
386 : flags(0), numberOfBuffers(0), priority(0) {}
387 };
388
389 //! A static function to determine the current RtAudio version.
390 static std::string getVersion( void );
391
392 //! A static function to determine the available compiled audio APIs.
393 /*!
394 The values returned in the std::vector can be compared against
395 the enumerated list values. Note that there can be more than one
396 API compiled for certain operating systems.
397 */
398 static void getCompiledApi( std::vector<RtAudio::Api> &apis );
399
400 //! The class constructor.
401 /*!
402 The constructor performs minor initialization tasks. An exception
403 can be thrown if no API support is compiled.
404
405 If no API argument is specified and multiple API support has been
406 compiled, the default order of use is JACK, ALSA, OSS (Linux
407 systems) and ASIO, DS (Windows systems).
408 */
409 RtAudio( RtAudio::Api api=UNSPECIFIED );
410
411 //! The destructor.
412 /*!
413 If a stream is running or open, it will be stopped and closed
414 automatically.
415 */
416 ~RtAudio();
417
418 //! Returns the audio API specifier for the current instance of RtAudio.
419 RtAudio::Api getCurrentApi( void );
420
421 //! A public function that queries for the number of audio devices available.
422 /*!
423 This function performs a system query of available devices each time it
424 is called, thus supporting devices connected \e after instantiation. If
425 a system error occurs during processing, a warning will be issued.
426 */
427 unsigned int getDeviceCount( void );
428
429 //! Return an RtAudio::DeviceInfo structure for a specified device number.
430 /*!
431
432 Any device integer between 0 and getDeviceCount() - 1 is valid.
433 If an invalid argument is provided, an RtAudioError (type = INVALID_USE)
434 will be thrown. If a device is busy or otherwise unavailable, the
435 structure member "probed" will have a value of "false" and all
436 other members are undefined. If the specified device is the
437 current default input or output device, the corresponding
438 "isDefault" member will have a value of "true".
439 */
440 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
441
442 //! A function that returns the index of the default output device.
443 /*!
444 If the underlying audio API does not provide a "default
445 device", or if no devices are available, the return value will be
446 0. Note that this is a valid device identifier and it is the
447 client's responsibility to verify that a device is available
448 before attempting to open a stream.
449 */
450 unsigned int getDefaultOutputDevice( void );
451
452 //! A function that returns the index of the default input device.
453 /*!
454 If the underlying audio API does not provide a "default
455 device", or if no devices are available, the return value will be
456 0. Note that this is a valid device identifier and it is the
457 client's responsibility to verify that a device is available
458 before attempting to open a stream.
459 */
460 unsigned int getDefaultInputDevice( void );
461
462 //! A public function for opening a stream with the specified parameters.
463 /*!
464 An RtAudioError (type = SYSTEM_ERROR) is thrown if a stream cannot be
465 opened with the specified parameters or an error occurs during
466 processing. An RtAudioError (type = INVALID_USE) is thrown if any
467 invalid device ID or channel number parameters are specified.
468
469 \param outputParameters Specifies output stream parameters to use
470 when opening a stream, including a device ID, number of channels,
471 and starting channel number. For input-only streams, this
472 argument should be NULL. The device ID is an index value between
473 0 and getDeviceCount() - 1.
474 \param inputParameters Specifies input stream parameters to use
475 when opening a stream, including a device ID, number of channels,
476 and starting channel number. For output-only streams, this
477 argument should be NULL. The device ID is an index value between
478 0 and getDeviceCount() - 1.
479 \param format An RtAudioFormat specifying the desired sample data format.
480 \param sampleRate The desired sample rate (sample frames per second).
481 \param *bufferFrames A pointer to a value indicating the desired
482 internal buffer size in sample frames. The actual value
483 used by the device is returned via the same pointer. A
484 value of zero can be specified, in which case the lowest
485 allowable value is determined.
486 \param callback A client-defined function that will be invoked
487 when input data is available and/or output data is needed.
488 \param userData An optional pointer to data that can be accessed
489 from within the callback function.
490 \param options An optional pointer to a structure containing various
491 global stream options, including a list of OR'ed RtAudioStreamFlags
492 and a suggested number of stream buffers that can be used to
493 control stream latency. More buffers typically result in more
494 robust performance, though at a cost of greater latency. If a
495 value of zero is specified, a system-specific median value is
496 chosen. If the RTAUDIO_MINIMIZE_LATENCY flag bit is set, the
497 lowest allowable value is used. The actual value used is
498 returned via the structure argument. The parameter is API dependent.
499 \param errorCallback A client-defined function that will be invoked
500 when an error has occured.
501 */
502 void openStream( RtAudio::StreamParameters *outputParameters,
503 RtAudio::StreamParameters *inputParameters,
504 RtAudioFormat format, unsigned int sampleRate,
505 unsigned int *bufferFrames, RtAudioCallback callback,
506 void *userData = NULL, RtAudio::StreamOptions *options = NULL, RtAudioErrorCallback errorCallback = NULL );
507
508 //! A function that closes a stream and frees any associated stream memory.
509 /*!
510 If a stream is not open, this function issues a warning and
511 returns (no exception is thrown).
512 */
513 void closeStream( void );
514
515 //! A function that starts a stream.
516 /*!
517 An RtAudioError (type = SYSTEM_ERROR) is thrown if an error occurs
518 during processing. An RtAudioError (type = INVALID_USE) is thrown if a
519 stream is not open. A warning is issued if the stream is already
520 running.
521 */
522 void startStream( void );
523
524 //! Stop a stream, allowing any samples remaining in the output queue to be played.
525 /*!
526 An RtAudioError (type = SYSTEM_ERROR) is thrown if an error occurs
527 during processing. An RtAudioError (type = INVALID_USE) is thrown if a
528 stream is not open. A warning is issued if the stream is already
529 stopped.
530 */
531 void stopStream( void );
532
533 //! Stop a stream, discarding any samples remaining in the input/output queue.
534 /*!
535 An RtAudioError (type = SYSTEM_ERROR) is thrown if an error occurs
536 during processing. An RtAudioError (type = INVALID_USE) is thrown if a
537 stream is not open. A warning is issued if the stream is already
538 stopped.
539 */
540 void abortStream( void );
541
542 //! Returns true if a stream is open and false if not.
543 bool isStreamOpen( void ) const;
544
545 //! Returns true if the stream is running and false if it is stopped or not open.
546 bool isStreamRunning( void ) const;
547
548 //! Returns the number of elapsed seconds since the stream was started.
549 /*!
550 If a stream is not open, an RtAudioError (type = INVALID_USE) will be thrown.
551 */
552 double getStreamTime( void );
553
554 //! Set the stream time to a time in seconds greater than or equal to 0.0.
555 /*!
556 If a stream is not open, an RtAudioError (type = INVALID_USE) will be thrown.
557 */
558 void setStreamTime( double time );
559
560 //! Returns the internal stream latency in sample frames.
561 /*!
562 The stream latency refers to delay in audio input and/or output
563 caused by internal buffering by the audio system and/or hardware.
564 For duplex streams, the returned value will represent the sum of
565 the input and output latencies. If a stream is not open, an
566 RtAudioError (type = INVALID_USE) will be thrown. If the API does not
567 report latency, the return value will be zero.
568 */
569 long getStreamLatency( void );
570
571 //! Returns actual sample rate in use by the stream.
572 /*!
573 On some systems, the sample rate used may be slightly different
574 than that specified in the stream parameters. If a stream is not
575 open, an RtAudioError (type = INVALID_USE) will be thrown.
576 */
577 unsigned int getStreamSampleRate( void );
578
579 //! Specify whether warning messages should be printed to stderr.
580 void showWarnings( bool value = true );
581
582 protected:
583
584 void openRtApi( RtAudio::Api api );
585 RtApi *rtapi_;
586 };
587
588 // Operating system dependent thread functionality.
589 #if defined(__WINDOWS_DS__) || defined(__WINDOWS_ASIO__) || defined(__WINDOWS_WASAPI__)
590
591 #ifndef NOMINMAX
592 #define NOMINMAX
593 #endif
594 #include <windows.h>
595 #include <process.h>
596
597 typedef uintptr_t ThreadHandle;
598 typedef CRITICAL_SECTION StreamMutex;
599
600 #elif defined(__LINUX_ALSA__) || defined(__LINUX_PULSE__) || defined(__UNIX_JACK__) || defined(__LINUX_OSS__) || defined(__MACOSX_CORE__)
601 // Using pthread library for various flavors of unix.
602 #include <pthread.h>
603
604 typedef pthread_t ThreadHandle;
605 typedef pthread_mutex_t StreamMutex;
606
607 #else // Setup for "dummy" behavior
608
609 #define __RTAUDIO_DUMMY__
610 typedef int ThreadHandle;
611 typedef int StreamMutex;
612
613 #endif
614
615 // This global structure type is used to pass callback information
616 // between the private RtAudio stream structure and global callback
617 // handling functions.
618 struct CallbackInfo {
619 void *object; // Used as a "this" pointer.
620 ThreadHandle thread;
621 void *callback;
622 void *userData;
623 void *errorCallback;
624 void *apiInfo; // void pointer for API specific callback information
625 bool isRunning;
626 bool doRealtime;
627 int priority;
628
629 // Default constructor.
CallbackInfoCallbackInfo630 CallbackInfo()
631 :object(0), callback(0), userData(0), errorCallback(0), apiInfo(0), isRunning(false), doRealtime(false), priority(0) {}
632 };
633
634 // **************************************************************** //
635 //
636 // RtApi class declaration.
637 //
638 // Subclasses of RtApi contain all API- and OS-specific code necessary
639 // to fully implement the RtAudio API.
640 //
641 // Note that RtApi is an abstract base class and cannot be
642 // explicitly instantiated. The class RtAudio will create an
643 // instance of an RtApi subclass (RtApiOss, RtApiAlsa,
644 // RtApiJack, RtApiCore, RtApiDs, or RtApiAsio).
645 //
646 // **************************************************************** //
647
648 #pragma pack(push, 1)
649 class S24 {
650
651 protected:
652 unsigned char c3[3];
653
654 public:
S24()655 S24() {}
656
657 S24& operator = ( const int& i ) {
658 c3[0] = (i & 0x000000ff);
659 c3[1] = (i & 0x0000ff00) >> 8;
660 c3[2] = (i & 0x00ff0000) >> 16;
661 return *this;
662 }
663
S24(const S24 & v)664 S24( const S24& v ) { *this = v; }
S24(const double & d)665 S24( const double& d ) { *this = (int) d; }
S24(const float & f)666 S24( const float& f ) { *this = (int) f; }
S24(const signed short & s)667 S24( const signed short& s ) { *this = (int) s; }
S24(const char & c)668 S24( const char& c ) { *this = (int) c; }
669
asInt()670 int asInt() {
671 int i = c3[0] | (c3[1] << 8) | (c3[2] << 16);
672 if (i & 0x800000) i |= ~0xffffff;
673 return i;
674 }
675 };
676 #pragma pack(pop)
677
678 #if defined( HAVE_GETTIMEOFDAY )
679 #include <sys/time.h>
680 #endif
681
682 #include <sstream>
683
684 class RTAUDIO_DLL_PUBLIC RtApi
685 {
686 public:
687
688 RtApi();
689 virtual ~RtApi();
690 virtual RtAudio::Api getCurrentApi( void ) = 0;
691 virtual unsigned int getDeviceCount( void ) = 0;
692 virtual RtAudio::DeviceInfo getDeviceInfo( unsigned int device ) = 0;
693 virtual unsigned int getDefaultInputDevice( void );
694 virtual unsigned int getDefaultOutputDevice( void );
695 void openStream( RtAudio::StreamParameters *outputParameters,
696 RtAudio::StreamParameters *inputParameters,
697 RtAudioFormat format, unsigned int sampleRate,
698 unsigned int *bufferFrames, RtAudioCallback callback,
699 void *userData, RtAudio::StreamOptions *options,
700 RtAudioErrorCallback errorCallback );
701 virtual void closeStream( void );
702 virtual void startStream( void ) = 0;
703 virtual void stopStream( void ) = 0;
704 virtual void abortStream( void ) = 0;
705 long getStreamLatency( void );
706 unsigned int getStreamSampleRate( void );
707 virtual double getStreamTime( void );
708 virtual void setStreamTime( double time );
isStreamOpen(void)709 bool isStreamOpen( void ) const { return stream_.state != STREAM_CLOSED; }
isStreamRunning(void)710 bool isStreamRunning( void ) const { return stream_.state == STREAM_RUNNING; }
showWarnings(bool value)711 void showWarnings( bool value ) { showWarnings_ = value; }
712
713
714 protected:
715
716 static const unsigned int MAX_SAMPLE_RATES;
717 static const unsigned int SAMPLE_RATES[];
718
719 enum { FAILURE, SUCCESS };
720
721 enum StreamState {
722 STREAM_STOPPED,
723 STREAM_STOPPING,
724 STREAM_RUNNING,
725 STREAM_CLOSED = -50
726 };
727
728 enum StreamMode {
729 OUTPUT,
730 INPUT,
731 DUPLEX,
732 UNINITIALIZED = -75
733 };
734
735 // A protected structure used for buffer conversion.
736 struct ConvertInfo {
737 int channels;
738 int inJump, outJump;
739 RtAudioFormat inFormat, outFormat;
740 std::vector<int> inOffset;
741 std::vector<int> outOffset;
742 };
743
744 // A protected structure for audio streams.
745 struct RtApiStream {
746 unsigned int device[2]; // Playback and record, respectively.
747 void *apiHandle; // void pointer for API specific stream handle information
748 StreamMode mode; // OUTPUT, INPUT, or DUPLEX.
749 StreamState state; // STOPPED, RUNNING, or CLOSED
750 char *userBuffer[2]; // Playback and record, respectively.
751 char *deviceBuffer;
752 bool doConvertBuffer[2]; // Playback and record, respectively.
753 bool userInterleaved;
754 bool deviceInterleaved[2]; // Playback and record, respectively.
755 bool doByteSwap[2]; // Playback and record, respectively.
756 unsigned int sampleRate;
757 unsigned int bufferSize;
758 unsigned int nBuffers;
759 unsigned int nUserChannels[2]; // Playback and record, respectively.
760 unsigned int nDeviceChannels[2]; // Playback and record channels, respectively.
761 unsigned int channelOffset[2]; // Playback and record, respectively.
762 unsigned long latency[2]; // Playback and record, respectively.
763 RtAudioFormat userFormat;
764 RtAudioFormat deviceFormat[2]; // Playback and record, respectively.
765 StreamMutex mutex;
766 CallbackInfo callbackInfo;
767 ConvertInfo convertInfo[2];
768 double streamTime; // Number of elapsed seconds since the stream started.
769
770 #if defined(HAVE_GETTIMEOFDAY)
771 struct timeval lastTickTimestamp;
772 #endif
773
RtApiStreamRtApiStream774 RtApiStream()
775 :apiHandle(0), deviceBuffer(0) { device[0] = 11111; device[1] = 11111; }
776 };
777
778 typedef S24 Int24;
779 typedef signed short Int16;
780 typedef signed int Int32;
781 typedef float Float32;
782 typedef double Float64;
783
784 std::ostringstream errorStream_;
785 std::string errorText_;
786 bool showWarnings_;
787 RtApiStream stream_;
788 bool firstErrorOccurred_;
789
790 /*!
791 Protected, api-specific method that attempts to open a device
792 with the given parameters. This function MUST be implemented by
793 all subclasses. If an error is encountered during the probe, a
794 "warning" message is reported and FAILURE is returned. A
795 successful probe is indicated by a return value of SUCCESS.
796 */
797 virtual bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
798 unsigned int firstChannel, unsigned int sampleRate,
799 RtAudioFormat format, unsigned int *bufferSize,
800 RtAudio::StreamOptions *options );
801
802 //! A protected function used to increment the stream time.
803 void tickStreamTime( void );
804
805 //! Protected common method to clear an RtApiStream structure.
806 void clearStreamInfo();
807
808 /*!
809 Protected common method that throws an RtAudioError (type =
810 INVALID_USE) if a stream is not open.
811 */
812 void verifyStream( void );
813
814 //! Protected common error method to allow global control over error handling.
815 void error( RtAudioError::Type type );
816
817 /*!
818 Protected method used to perform format, channel number, and/or interleaving
819 conversions between the user and device buffers.
820 */
821 void convertBuffer( char *outBuffer, char *inBuffer, ConvertInfo &info );
822
823 //! Protected common method used to perform byte-swapping on buffers.
824 void byteSwapBuffer( char *buffer, unsigned int samples, RtAudioFormat format );
825
826 //! Protected common method that returns the number of bytes for a given format.
827 unsigned int formatBytes( RtAudioFormat format );
828
829 //! Protected common method that sets up the parameters for buffer conversion.
830 void setConvertInfo( StreamMode mode, unsigned int firstChannel );
831 };
832
833 // **************************************************************** //
834 //
835 // Inline RtAudio definitions.
836 //
837 // **************************************************************** //
838
getCurrentApi(void)839 inline RtAudio::Api RtAudio :: getCurrentApi( void ) { return rtapi_->getCurrentApi(); }
getDeviceCount(void)840 inline unsigned int RtAudio :: getDeviceCount( void ) { return rtapi_->getDeviceCount(); }
getDeviceInfo(unsigned int device)841 inline RtAudio::DeviceInfo RtAudio :: getDeviceInfo( unsigned int device ) { return rtapi_->getDeviceInfo( device ); }
getDefaultInputDevice(void)842 inline unsigned int RtAudio :: getDefaultInputDevice( void ) { return rtapi_->getDefaultInputDevice(); }
getDefaultOutputDevice(void)843 inline unsigned int RtAudio :: getDefaultOutputDevice( void ) { return rtapi_->getDefaultOutputDevice(); }
closeStream(void)844 inline void RtAudio :: closeStream( void ) { return rtapi_->closeStream(); }
startStream(void)845 inline void RtAudio :: startStream( void ) { return rtapi_->startStream(); }
stopStream(void)846 inline void RtAudio :: stopStream( void ) { return rtapi_->stopStream(); }
abortStream(void)847 inline void RtAudio :: abortStream( void ) { return rtapi_->abortStream(); }
isStreamOpen(void)848 inline bool RtAudio :: isStreamOpen( void ) const { return rtapi_->isStreamOpen(); }
isStreamRunning(void)849 inline bool RtAudio :: isStreamRunning( void ) const { return rtapi_->isStreamRunning(); }
getStreamLatency(void)850 inline long RtAudio :: getStreamLatency( void ) { return rtapi_->getStreamLatency(); }
getStreamSampleRate(void)851 inline unsigned int RtAudio :: getStreamSampleRate( void ) { return rtapi_->getStreamSampleRate(); }
getStreamTime(void)852 inline double RtAudio :: getStreamTime( void ) { return rtapi_->getStreamTime(); }
setStreamTime(double time)853 inline void RtAudio :: setStreamTime( double time ) { return rtapi_->setStreamTime( time ); }
showWarnings(bool value)854 inline void RtAudio :: showWarnings( bool value ) { rtapi_->showWarnings( value ); }
855
856 // RtApi Subclass prototypes.
857
858 #if defined(__MACOSX_CORE__)
859
860 #include <CoreAudio/AudioHardware.h>
861
862 class RtApiCore: public RtApi
863 {
864 public:
865
866 RtApiCore();
867 ~RtApiCore();
getCurrentApi(void)868 RtAudio::Api getCurrentApi( void ) { return RtAudio::MACOSX_CORE; }
869 unsigned int getDeviceCount( void );
870 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
871 unsigned int getDefaultOutputDevice( void );
872 unsigned int getDefaultInputDevice( void );
873 void closeStream( void );
874 void startStream( void );
875 void stopStream( void );
876 void abortStream( void );
877 long getStreamLatency( void );
878
879 // This function is intended for internal use only. It must be
880 // public because it is called by the internal callback handler,
881 // which is not a member of RtAudio. External use of this function
882 // will most likely produce highly undesireable results!
883 bool callbackEvent( AudioDeviceID deviceId,
884 const AudioBufferList *inBufferList,
885 const AudioBufferList *outBufferList );
886
887 private:
888
889 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
890 unsigned int firstChannel, unsigned int sampleRate,
891 RtAudioFormat format, unsigned int *bufferSize,
892 RtAudio::StreamOptions *options );
893 static const char* getErrorCode( OSStatus code );
894 };
895
896 #endif
897
898 #if defined(__UNIX_JACK__)
899
900 class RtApiJack: public RtApi
901 {
902 public:
903
904 RtApiJack();
905 ~RtApiJack();
getCurrentApi(void)906 RtAudio::Api getCurrentApi( void ) { return RtAudio::UNIX_JACK; }
907 unsigned int getDeviceCount( void );
908 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
909 void closeStream( void );
910 void startStream( void );
911 void stopStream( void );
912 void abortStream( void );
913 long getStreamLatency( void );
914
915 // This function is intended for internal use only. It must be
916 // public because it is called by the internal callback handler,
917 // which is not a member of RtAudio. External use of this function
918 // will most likely produce highly undesireable results!
919 bool callbackEvent( unsigned long nframes );
920
921 private:
922
923 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
924 unsigned int firstChannel, unsigned int sampleRate,
925 RtAudioFormat format, unsigned int *bufferSize,
926 RtAudio::StreamOptions *options );
927
928 bool shouldAutoconnect_;
929 };
930
931 #endif
932
933 #if defined(__WINDOWS_ASIO__)
934
935 class RtApiAsio: public RtApi
936 {
937 public:
938
939 RtApiAsio();
940 ~RtApiAsio();
getCurrentApi(void)941 RtAudio::Api getCurrentApi( void ) { return RtAudio::WINDOWS_ASIO; }
942 unsigned int getDeviceCount( void );
943 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
944 void closeStream( void );
945 void startStream( void );
946 void stopStream( void );
947 void abortStream( void );
948 long getStreamLatency( void );
949
950 // This function is intended for internal use only. It must be
951 // public because it is called by the internal callback handler,
952 // which is not a member of RtAudio. External use of this function
953 // will most likely produce highly undesireable results!
954 bool callbackEvent( long bufferIndex );
955
956 private:
957
958 std::vector<RtAudio::DeviceInfo> devices_;
959 void saveDeviceInfo( void );
960 bool coInitialized_;
961 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
962 unsigned int firstChannel, unsigned int sampleRate,
963 RtAudioFormat format, unsigned int *bufferSize,
964 RtAudio::StreamOptions *options );
965 };
966
967 #endif
968
969 #if defined(__WINDOWS_DS__)
970
971 class RtApiDs: public RtApi
972 {
973 public:
974
975 RtApiDs();
976 ~RtApiDs();
getCurrentApi(void)977 RtAudio::Api getCurrentApi( void ) { return RtAudio::WINDOWS_DS; }
978 unsigned int getDeviceCount( void );
979 unsigned int getDefaultOutputDevice( void );
980 unsigned int getDefaultInputDevice( void );
981 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
982 void closeStream( void );
983 void startStream( void );
984 void stopStream( void );
985 void abortStream( void );
986 long getStreamLatency( void );
987
988 // This function is intended for internal use only. It must be
989 // public because it is called by the internal callback handler,
990 // which is not a member of RtAudio. External use of this function
991 // will most likely produce highly undesireable results!
992 void callbackEvent( void );
993
994 private:
995
996 bool coInitialized_;
997 bool buffersRolling;
998 long duplexPrerollBytes;
999 std::vector<struct DsDevice> dsDevices;
1000 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
1001 unsigned int firstChannel, unsigned int sampleRate,
1002 RtAudioFormat format, unsigned int *bufferSize,
1003 RtAudio::StreamOptions *options );
1004 };
1005
1006 #endif
1007
1008 #if defined(__WINDOWS_WASAPI__)
1009
1010 struct IMMDeviceEnumerator;
1011
1012 class RtApiWasapi : public RtApi
1013 {
1014 public:
1015 RtApiWasapi();
1016 ~RtApiWasapi();
1017
getCurrentApi(void)1018 RtAudio::Api getCurrentApi( void ) { return RtAudio::WINDOWS_WASAPI; }
1019 unsigned int getDeviceCount( void );
1020 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
1021 unsigned int getDefaultOutputDevice( void );
1022 unsigned int getDefaultInputDevice( void );
1023 void closeStream( void );
1024 void startStream( void );
1025 void stopStream( void );
1026 void abortStream( void );
1027
1028 private:
1029 bool coInitialized_;
1030 IMMDeviceEnumerator* deviceEnumerator_;
1031
1032 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
1033 unsigned int firstChannel, unsigned int sampleRate,
1034 RtAudioFormat format, unsigned int* bufferSize,
1035 RtAudio::StreamOptions* options );
1036
1037 static DWORD WINAPI runWasapiThread( void* wasapiPtr );
1038 static DWORD WINAPI stopWasapiThread( void* wasapiPtr );
1039 static DWORD WINAPI abortWasapiThread( void* wasapiPtr );
1040 void wasapiThread();
1041 };
1042
1043 #endif
1044
1045 #if defined(__LINUX_ALSA__)
1046
1047 class RtApiAlsa: public RtApi
1048 {
1049 public:
1050
1051 RtApiAlsa();
1052 ~RtApiAlsa();
getCurrentApi()1053 RtAudio::Api getCurrentApi() { return RtAudio::LINUX_ALSA; }
1054 unsigned int getDeviceCount( void );
1055 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
1056 void closeStream( void );
1057 void startStream( void );
1058 void stopStream( void );
1059 void abortStream( void );
1060
1061 // This function is intended for internal use only. It must be
1062 // public because it is called by the internal callback handler,
1063 // which is not a member of RtAudio. External use of this function
1064 // will most likely produce highly undesireable results!
1065 void callbackEvent( void );
1066
1067 private:
1068
1069 std::vector<RtAudio::DeviceInfo> devices_;
1070 void saveDeviceInfo( void );
1071 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
1072 unsigned int firstChannel, unsigned int sampleRate,
1073 RtAudioFormat format, unsigned int *bufferSize,
1074 RtAudio::StreamOptions *options );
1075 };
1076
1077 #endif
1078
1079 #if defined(__LINUX_PULSE__)
1080
1081 class RtApiPulse: public RtApi
1082 {
1083 public:
1084 ~RtApiPulse();
getCurrentApi()1085 RtAudio::Api getCurrentApi() { return RtAudio::LINUX_PULSE; }
1086 unsigned int getDeviceCount( void );
1087 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
1088 void closeStream( void );
1089 void startStream( void );
1090 void stopStream( void );
1091 void abortStream( void );
1092
1093 // This function is intended for internal use only. It must be
1094 // public because it is called by the internal callback handler,
1095 // which is not a member of RtAudio. External use of this function
1096 // will most likely produce highly undesireable results!
1097 void callbackEvent( void );
1098
1099 private:
1100
1101 std::vector<RtAudio::DeviceInfo> devices_;
1102 void saveDeviceInfo( void );
1103 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
1104 unsigned int firstChannel, unsigned int sampleRate,
1105 RtAudioFormat format, unsigned int *bufferSize,
1106 RtAudio::StreamOptions *options );
1107 };
1108
1109 #endif
1110
1111 #if defined(__LINUX_OSS__)
1112
1113 class RtApiOss: public RtApi
1114 {
1115 public:
1116
1117 RtApiOss();
1118 ~RtApiOss();
getCurrentApi()1119 RtAudio::Api getCurrentApi() { return RtAudio::LINUX_OSS; }
1120 unsigned int getDeviceCount( void );
1121 RtAudio::DeviceInfo getDeviceInfo( unsigned int device );
1122 void closeStream( void );
1123 void startStream( void );
1124 void stopStream( void );
1125 void abortStream( void );
1126
1127 // This function is intended for internal use only. It must be
1128 // public because it is called by the internal callback handler,
1129 // which is not a member of RtAudio. External use of this function
1130 // will most likely produce highly undesireable results!
1131 void callbackEvent( void );
1132
1133 private:
1134
1135 bool probeDeviceOpen( unsigned int device, StreamMode mode, unsigned int channels,
1136 unsigned int firstChannel, unsigned int sampleRate,
1137 RtAudioFormat format, unsigned int *bufferSize,
1138 RtAudio::StreamOptions *options );
1139 };
1140
1141 #endif
1142
1143 #if defined(__RTAUDIO_DUMMY__)
1144
1145 class RtApiDummy: public RtApi
1146 {
1147 public:
1148
RtApiDummy()1149 RtApiDummy() { errorText_ = "RtApiDummy: This class provides no functionality."; error( RtAudioError::WARNING ); }
getCurrentApi(void)1150 RtAudio::Api getCurrentApi( void ) { return RtAudio::RTAUDIO_DUMMY; }
getDeviceCount(void)1151 unsigned int getDeviceCount( void ) { return 0; }
getDeviceInfo(unsigned int)1152 RtAudio::DeviceInfo getDeviceInfo( unsigned int /*device*/ ) { RtAudio::DeviceInfo info; return info; }
closeStream(void)1153 void closeStream( void ) {}
startStream(void)1154 void startStream( void ) {}
stopStream(void)1155 void stopStream( void ) {}
abortStream(void)1156 void abortStream( void ) {}
1157
1158 private:
1159
probeDeviceOpen(unsigned int,StreamMode,unsigned int,unsigned int,unsigned int,RtAudioFormat,unsigned int *,RtAudio::StreamOptions *)1160 bool probeDeviceOpen( unsigned int /*device*/, StreamMode /*mode*/, unsigned int /*channels*/,
1161 unsigned int /*firstChannel*/, unsigned int /*sampleRate*/,
1162 RtAudioFormat /*format*/, unsigned int * /*bufferSize*/,
1163 RtAudio::StreamOptions * /*options*/ ) { return false; }
1164 };
1165
1166 #endif
1167
1168 #endif
1169
1170 // Indentation settings for Vim and Emacs
1171 //
1172 // Local Variables:
1173 // c-basic-offset: 2
1174 // indent-tabs-mode: nil
1175 // End:
1176 //
1177 // vim: et sts=2 sw=2
1178