1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
#ifndef foosimplehfoo
#define foosimplehfoo
/* $Id$ */
/***
This file is part of polypaudio.
polypaudio is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.
polypaudio is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with polypaudio; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA.
***/
#include <sys/types.h>
#include <polyp/sample.h>
#include <polyp/def.h>
#include <polyp/cdecl.h>
/** \page simple Simple API
*
* \section overv_sec Overview
*
* The simple API is designed for applications with very basic sound
* playback or capture needs. It can only support a single stream per
* connection and has no handling of complex features like events, channel
* mappings and volume control. It is, however, very simple to use and
* quite sufficent for many programs.
*
* \section conn_sec Connecting
*
* The first step before using the sound system is to connect to the
* server. This is normally done this way:
*
* \code
* pa_simple *s;
* pa_sample_spec ss;
*
* ss.format = S16_NE;
* ss.channels = 2;
* ss.rate = 44100;
*
* s = pa_simple_new(NULL, // Use the default server.
* "Fooapp", // Our application's name.
* PA_STREAM_PLAYBACK,
* NULL, // Use the default device.
* "Music", // Description of our stream.
* &ss, // Our sample format.
* NULL, // Use default buffering attributes.
* NULL, // Ignore error code.
* );
* \endcode
*
* At this point a connected object is returned, or NULL if there was a
* problem connecting.
*
* \section transfer_sec Transferring data
*
* Once the connection is established to the server, data can start flowing.
* Using the connection is very similar to the normal read() and write()
* system calls. The main difference is that they're call pa_simple_read()
* and pa_simple_write(). Note that these operation are always blocking.
*
* \section ctrl_sec Buffer control
*
* If a playback stream is used then a few other operations are available:
*
* \li pa_simple_drain() - Will wait for all sent data to finish playing.
* \li pa_simple_flush() - Will throw away all data currently in buffers.
* \li pa_simple_get_playback_latency() - Will return the total latency of
* the playback pipeline.
*
* \section cleanup_sec Cleanup
*
* Once playback or capture is complete, the connection should be closed
* and resources freed. This is done through:
*
* \code
* pa_simple_free(s);
* \endcode
*/
/** \file
* A simple but limited synchronous playback and recording
* API. This is a synchronous, simplified wrapper around the standard
* asynchronous API. */
/** \example pacat-simple.c
* A simple playback tool using the simple API */
/** \example parec-simple.c
* A simple recording tool using the simple API */
PA_C_DECL_BEGIN
/** \struct pa_simple
* An opaque simple connection object */
typedef struct pa_simple pa_simple;
/** Create a new connection to the server */
pa_simple* pa_simple_new(
const char *server, /**< Server name, or NULL for default */
const char *name, /**< A descriptive name for this client (application name, ...) */
pa_stream_direction_t dir, /**< Open this stream for recording or playback? */
const char *dev, /**< Sink (resp. source) name, or NULL for default */
const char *stream_name, /**< A descriptive name for this client (application name, song title, ...) */
const pa_sample_spec *ss, /**< The sample type to use */
const pa_buffer_attr *attr, /**< Buffering attributes, or NULL for default */
int *error /**< A pointer where the error code is stored when the routine returns NULL. It is OK to pass NULL here. */
);
/** Close and free the connection to the server. The connection objects becomes invalid when this is called. */
void pa_simple_free(pa_simple *s);
/** Write some data to the server */
int pa_simple_write(pa_simple *s, const void*data, size_t length, int *error);
/** Wait until all data already written is played by the daemon */
int pa_simple_drain(pa_simple *s, int *error);
/** Read some data from the server */
int pa_simple_read(pa_simple *s, void*data, size_t length, int *error);
/** Return the playback latency. \since 0.5 */
pa_usec_t pa_simple_get_playback_latency(pa_simple *s, int *error);
/** Flush the playback buffer. \since 0.5 */
int pa_simple_flush(pa_simple *s, int *error);
PA_C_DECL_END
#endif
|
