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
  33 /** \page simple Simple API
  34  *
  35  * \section overv_sec Overview
  36  *
  37  * The simple API is designed for applications with very basic sound
  38  * playback or capture needs. It can only support a single stream per
  39  * connection and has no handling of complex features like events, channel
  40  * mappings and volume control. It is, however, very simple to use and
  41  * quite sufficent for many programs.
  42  *
  43  * \section conn_sec Connecting
  44  *
  45  * The first step before using the sound system is to connect to the
  46  * server. This is normally done this way:
  47  *
  48  * \code
  49  * pa_simple *s;
  50  * pa_sample_spec ss;
  51  *
  52  * ss.format = PA_SAMPLE_S16NE;
  53  * ss.channels = 2;
  54  * ss.rate = 44100;
  55  *
  56  * s = pa_simple_new(NULL,               // Use the default server.
  57  *                   "Fooapp",           // Our application's name.
  58  *                   PA_STREAM_PLAYBACK,
  59  *                   NULL,               // Use the default device.
  60  *                   "Music",            // Description of our stream.
  61  *                   &ss,                // Our sample format.
  62  *                   NULL,               // Use default channel map
  63  *                   NULL,               // Use default buffering attributes.
  64  *                   NULL,               // Ignore error code.
  65  *                   );
  66  * \endcode
  67  *
  68  * At this point a connected object is returned, or NULL if there was a
  69  * problem connecting.
  70  *
  71  * \section transfer_sec Transferring data
  72  *
  73  * Once the connection is established to the server, data can start flowing.
  74  * Using the connection is very similar to the normal read() and write()
  75  * system calls. The main difference is that they're call pa_simple_read()
  76  * and pa_simple_write(). Note that these operations always block.
  77  *
  78  * \section ctrl_sec Buffer control
  79  *
  80  * If a playback stream is used then a few other operations are available:
  81  *
  82  * \li pa_simple_drain() - Will wait for all sent data to finish playing.
  83  * \li pa_simple_flush() - Will throw away all data currently in buffers.
  84  * \li pa_simple_get_playback_latency() - Will return the total latency of
  85  *                                        the playback pipeline.
  86  *
  87  * \section cleanup_sec Cleanup
  88  *
  89  * Once playback or capture is complete, the connection should be closed
  90  * and resources freed. This is done through:
  91  *
  92  * \code
  93  * pa_simple_free(s);
  94  * \endcode
  95  */
  96
  97 /** \file
  98  * A simple but limited synchronous playback and recording
  99  * API. This is a synchronous, simplified wrapper around the standard
 100  * asynchronous API. */
 101
 102 /** \example pacat-simple.c
 103  * A simple playback tool using the simple API */
 104
 105 /** \example parec-simple.c
 106  * A simple recording tool using the simple API */
 107
 108 PA_C_DECL_BEGIN
 109
 110 /** \struct pa_simple
 111  * An opaque simple connection object */
 112 typedef struct pa_simple pa_simple;
 113
 114 /** Create a new connection to the server */
 115 pa_simple* pa_simple_new(
 116     const char *server,                 /**< Server name, or NULL for default */
 117     const char *name,                   /**< A descriptive name for this client (application name, ...) */
 118     pa_stream_direction_t dir,          /**< Open this stream for recording or playback? */
 119     const char *dev,                    /**< Sink (resp. source) name, or NULL for default */
 120     const char *stream_name,            /**< A descriptive name for this client (application name, song title, ...) */
 121     const pa_sample_spec *ss,           /**< The sample type to use */
 122     const pa_channel_map *map,          /**< The channel map to use, or NULL for default */
 123     const pa_buffer_attr *attr,         /**< Buffering attributes, or NULL for default */
 124     int *error                          /**< A pointer where the error code is stored when the routine returns NULL. It is OK to pass NULL here. */
 125     );
 126
 127 /** Close and free the connection to the server. The connection objects becomes invalid when this is called. */
 128 void pa_simple_free(pa_simple *s);
 129
 130 /** Write some data to the server */
 131 int pa_simple_write(pa_simple *s, const void*data, size_t bytes, int *error);
 132
 133 /** Wait until all data already written is played by the daemon */
 134 int pa_simple_drain(pa_simple *s, int *error);
 135
 136 /** Read some data from the server */
 137 int pa_simple_read(pa_simple *s, void*data, size_t bytes, int *error);
 138
 139 /** Return the playback latency. */
 140 pa_usec_t pa_simple_get_latency(pa_simple *s, int *error);
 141
 142 /** Flush the playback buffer. */
 143 int pa_simple_flush(pa_simple *s, int *error);
 144
 145 PA_C_DECL_END
 146
 147 #endif