code.delx.au - pulseaudio/blob - src/pulse/simple.h

   1 #ifndef foosimplehfoo
   2 #define foosimplehfoo
   3
   4 /***
   5   This file is part of PulseAudio.
   6
   7   Copyright 2004-2006 Lennart Poettering
   8   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
   9
  10   PulseAudio is free software; you can redistribute it and/or modify
  11   it under the terms of the GNU Lesser General Public License as published
  12   by the Free Software Foundation; either version 2 of the License,
  13   or (at your option) any later version.
  14
  15   PulseAudio is distributed in the hope that it will be useful, but
  16   WITHOUT ANY WARRANTY; without even the implied warranty of
  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with PulseAudio; if not, write to the Free Software
  22   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  23   USA.
  24 ***/
  25
  26 #include <sys/types.h>
  27
  28 #include <pulse/sample.h>
  29 #include <pulse/channelmap.h>
  30 #include <pulse/def.h>
  31 #include <pulse/cdecl.h>
  32 #include <pulse/version.h>
  33
  34 /** \page simple Simple API
  35  *
  36  * \section overv_sec Overview
  37  *
  38  * The simple API is designed for applications with very basic sound
  39  * playback or capture needs. It can only support a single stream per
  40  * connection and has no handling of complex features like events, channel
  41  * mappings and volume control. It is, however, very simple to use and
  42  * quite sufficent for many programs.
  43  *
  44  * \section conn_sec Connecting
  45  *
  46  * The first step before using the sound system is to connect to the
  47  * server. This is normally done this way:
  48  *
  49  * \code
  50  * pa_simple *s;
  51  * pa_sample_spec ss;
  52  *
  53  * ss.format = PA_SAMPLE_S16NE;
  54  * ss.channels = 2;
  55  * ss.rate = 44100;
  56  *
  57  * s = pa_simple_new(NULL,               // Use the default server.
  58  *                   "Fooapp",           // Our application's name.
  59  *                   PA_STREAM_PLAYBACK,
  60  *                   NULL,               // Use the default device.
  61  *                   "Music",            // Description of our stream.
  62  *                   &ss,                // Our sample format.
  63  *                   NULL,               // Use default channel map
  64  *                   NULL,               // Use default buffering attributes.
  65  *                   NULL,               // Ignore error code.
  66  *                   );
  67  * \endcode
  68  *
  69  * At this point a connected object is returned, or NULL if there was a
  70  * problem connecting.
  71  *
  72  * \section transfer_sec Transferring data
  73  *
  74  * Once the connection is established to the server, data can start flowing.
  75  * Using the connection is very similar to the normal read() and write()
  76  * system calls. The main difference is that they're call pa_simple_read()
  77  * and pa_simple_write(). Note that these operations always block.
  78  *
  79  * \section ctrl_sec Buffer control
  80  *
  81  * If a playback stream is used then a few other operations are available:
  82  *
  83  * \li pa_simple_drain() - Will wait for all sent data to finish playing.
  84  * \li pa_simple_flush() - Will throw away all data currently in buffers.
  85  * \li pa_simple_get_playback_latency() - Will return the total latency of
  86  *                                        the playback pipeline.
  87  *
  88  * \section cleanup_sec Cleanup
  89  *
  90  * Once playback or capture is complete, the connection should be closed
  91  * and resources freed. This is done through:
  92  *
  93  * \code
  94  * pa_simple_free(s);
  95  * \endcode
  96  */
  97
  98 /** \file
  99  * A simple but limited synchronous playback and recording
 100  * API. This is a synchronous, simplified wrapper around the standard
 101  * asynchronous API. */
 102
 103 /** \example pacat-simple.c
 104  * A simple playback tool using the simple API */
 105
 106 /** \example parec-simple.c
 107  * A simple recording tool using the simple API */
 108
 109 PA_C_DECL_BEGIN
 110
 111 /** \struct pa_simple
 112  * An opaque simple connection object */
 113 typedef struct pa_simple pa_simple;
 114
 115 /** Create a new connection to the server */
 116 pa_simple* pa_simple_new(
 117     const char *server,                 /**< Server name, or NULL for default */
 118     const char *name,                   /**< A descriptive name for this client (application name, ...) */
 119     pa_stream_direction_t dir,          /**< Open this stream for recording or playback? */
 120     const char *dev,                    /**< Sink (resp. source) name, or NULL for default */
 121     const char *stream_name,            /**< A descriptive name for this client (application name, song title, ...) */
 122     const pa_sample_spec *ss,           /**< The sample type to use */
 123     const pa_channel_map *map,          /**< The channel map to use, or NULL for default */
 124     const pa_buffer_attr *attr,         /**< Buffering attributes, or NULL for default */
 125     int *error                          /**< A pointer where the error code is stored when the routine returns NULL. It is OK to pass NULL here. */
 126     );
 127
 128 /** Close and free the connection to the server. The connection objects becomes invalid when this is called. */
 129 void pa_simple_free(pa_simple *s);
 130
 131 /** Write some data to the server */
 132 int pa_simple_write(pa_simple *s, const void*data, size_t bytes, int *error);
 133
 134 /** Wait until all data already written is played by the daemon */
 135 int pa_simple_drain(pa_simple *s, int *error);
 136
 137 /** Read some data from the server */
 138 int pa_simple_read(pa_simple *s, void*data, size_t bytes, int *error);
 139
 140 /** Return the playback latency. */
 141 pa_usec_t pa_simple_get_latency(pa_simple *s, int *error);
 142
 143 /** Flush the playback buffer. */
 144 int pa_simple_flush(pa_simple *s, int *error);
 145
 146 PA_C_DECL_END
 147
 148 #endif