portaudio/include/pa_linux_alsa.h

#ifndef PA_LINUX_ALSA_H
#define PA_LINUX_ALSA_H

/*
 * $Id: pa_linux_alsa.h 1414 2009-05-24 17:02:10Z aknudsen $
 * PortAudio Portable Real-Time Audio Library
 * ALSA-specific extensions
 *
 * Copyright (c) 1999-2000 Ross Bencina and Phil Burk
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * The text above constitutes the entire PortAudio license; however, 
 * the PortAudio community also makes the following non-binding requests:
 *
 * Any person wishing to distribute modifications to the Software is
 * requested to send the modifications to the original developer so that
 * they can be incorporated into the canonical version. It is also 
 * requested that these non-binding requests be included along with the 
 * license above.
 */

/** @file
 *  @ingroup public_header
 *  @brief ALSA-specific PortAudio API extension header file.
 */
#include "portaudio.h"

#ifdef __cplusplus
extern "C" {
#endif

typedef struct PaAlsaStreamInfo
{
    unsigned long size;
    PaHostApiTypeId hostApiType;
    unsigned long version;

    const char *deviceString;
}
PaAlsaStreamInfo;

/** Initialize host API specific structure, call this before setting relevant attributes. */
void PaAlsa_InitializeStreamInfo( PaAlsaStreamInfo *info );

/** Instruct whether to enable real-time priority when starting the audio thread.
 *
 * If this is turned on by the stream is started, the audio callback thread will be created
 * with the FIFO scheduling policy, which is suitable for realtime operation.
 **/
void PaAlsa_EnableRealtimeScheduling( PaStream *s, int enable );

#if 0
void PaAlsa_EnableWatchdog( PaStream *s, int enable );
#endif

/** Get the ALSA-lib card index of this stream's input device. */
PaError PaAlsa_GetStreamInputCard( PaStream *s, int *card );

/** Get the ALSA-lib card index of this stream's output device. */
PaError PaAlsa_GetStreamOutputCard( PaStream *s, int *card );

/** Set the number of periods (buffer fragments) to configure devices with.
 *
 * By default the number of periods is 4, this is the lowest number of periods that works well on
 * the author's soundcard.
 * @param numPeriods The number of periods.
 */
PaError PaAlsa_SetNumPeriods( int numPeriods );

/** Set the maximum number of times to retry opening busy device (sleeping for a
 * short interval inbetween).
 */
PaError PaAlsa_SetRetriesBusy( int retries );

#ifdef __cplusplus
}
#endif

#endif
1	#ifndef PA_LINUX_ALSA_H
2	#define PA_LINUX_ALSA_H
3
4	/*
5	* $Id: pa_linux_alsa.h 1414 2009-05-24 17:02:10Z aknudsen $
6	* PortAudio Portable Real-Time Audio Library
7	* ALSA-specific extensions
8	*
9	* Copyright (c) 1999-2000 Ross Bencina and Phil Burk
10	*
11	* Permission is hereby granted, free of charge, to any person obtaining
12	* a copy of this software and associated documentation files
13	* (the "Software"), to deal in the Software without restriction,
14	* including without limitation the rights to use, copy, modify, merge,
15	* publish, distribute, sublicense, and/or sell copies of the Software,
16	* and to permit persons to whom the Software is furnished to do so,
17	* subject to the following conditions:
18	*
19	* The above copyright notice and this permission notice shall be
20	* included in all copies or substantial portions of the Software.
21	*
22	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
23	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
25	* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
26	* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
27	* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
28	* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
29	*/
30
31	/*
32	* The text above constitutes the entire PortAudio license; however,
33	* the PortAudio community also makes the following non-binding requests:
34	*
35	* Any person wishing to distribute modifications to the Software is
36	* requested to send the modifications to the original developer so that
37	* they can be incorporated into the canonical version. It is also
38	* requested that these non-binding requests be included along with the
39	* license above.
40	*/
41
42	/** @file
43	* @ingroup public_header
44	* @brief ALSA-specific PortAudio API extension header file.
45	*/
46	#include "portaudio.h"
47
48	#ifdef __cplusplus
49	extern "C" {
50	#endif
51
52	typedef struct PaAlsaStreamInfo
53	{
54	unsigned long size;
55	PaHostApiTypeId hostApiType;
56	unsigned long version;
57
58	const char *deviceString;
59	}
60	PaAlsaStreamInfo;
61
62	/** Initialize host API specific structure, call this before setting relevant attributes. */
63	void PaAlsa_InitializeStreamInfo( PaAlsaStreamInfo *info );
64
65	/** Instruct whether to enable real-time priority when starting the audio thread.
66	*
67	* If this is turned on by the stream is started, the audio callback thread will be created
68	* with the FIFO scheduling policy, which is suitable for realtime operation.
69	**/
70	void PaAlsa_EnableRealtimeScheduling( PaStream *s, int enable );
71
72	#if 0
73	void PaAlsa_EnableWatchdog( PaStream *s, int enable );
74	#endif
75
76	/** Get the ALSA-lib card index of this stream's input device. */
77	PaError PaAlsa_GetStreamInputCard( PaStream s, int card );
78
79	/** Get the ALSA-lib card index of this stream's output device. */
80	PaError PaAlsa_GetStreamOutputCard( PaStream s, int card );
81
82	/** Set the number of periods (buffer fragments) to configure devices with.
83	*
84	* By default the number of periods is 4, this is the lowest number of periods that works well on
85	* the author's soundcard.
86	* @param numPeriods The number of periods.
87	*/
88	PaError PaAlsa_SetNumPeriods( int numPeriods );
89
90	/** Set the maximum number of times to retry opening busy device (sleeping for a
91	* short interval inbetween).
92	*/
93	PaError PaAlsa_SetRetriesBusy( int retries );
94
95	#ifdef __cplusplus
96	}
97	#endif
98
99	#endif