src/pulse/simple.h

   1 #ifndef foosimplehfoo
   2 #define foosimplehfoo
   3
   4 /* $Id$ */
   5
   6 /***
   7   This file is part of PulseAudio.
   8
   9   Copyright 2004-2006 Lennart Poettering
  10   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
  11
  12   PulseAudio is free software; you can redistribute it and/or modify
  13   it under the terms of the GNU Lesser General Public License as published
  14   by the Free Software Foundation; either version 2 of the License,
  15   or (at your option) any later version.
  16
  17   PulseAudio is distributed in the hope that it will be useful, but
  18   WITHOUT ANY WARRANTY; without even the implied warranty of
  19   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  20   General Public License for more details.
  21
  22   You should have received a copy of the GNU Lesser General Public License
  23   along with PulseAudio; if not, write to the Free Software
  24   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  25   USA.
  26 ***/
  27
  28 #include <sys/types.h>
  29
  30 #include <pulse/sample.h>
  31 #include <pulse/channelmap.h>
  32 #include <pulse/def.h>
  33 #include <pulse/cdecl.h>
  34
  35 /** \page simple Simple API
  36  *
  37  * \section overv_sec Overview
  38  *
  39  * The simple API is designed for applications with very basic sound
  40  * playback or capture needs. It can only support a single stream per
  41  * connection and has no handling of complex features like events, channel
  42  * mappings and volume control. It is, however, very simple to use and
  43  * quite sufficent for many programs.
  44  *
  45  * \section conn_sec Connecting
  46  *
  47  * The first step before using the sound system is to connect to the
  48  * server. This is normally done this way:
  49  *
  50  * \code
  51  * pa_simple *s;
  52  * pa_sample_spec ss;
  53  *
  54  * ss.format = PA_SAMPLE_S16NE;
  55  * ss.channels = 2;
  56  * ss.rate = 44100;
  57  *
  58  * s = pa_simple_new(NULL,               // Use the default server.
  59  *                   "Fooapp",           // Our application's name.
  60  *                   PA_STREAM_PLAYBACK,
  61  *                   NULL,               // Use the default device.
  62  *                   "Music",            // Description of our stream.
  63  *                   &ss,                // Our sample format.
  64  *                   NULL,               // Use default channel map
  65  *                   NULL,               // Use default buffering attributes.
  66  *                   NULL,               // Ignore error code.
  67  *                   );
  68  * \endcode
  69  *
  70  * At this point a connected object is returned, or NULL if there was a
  71  * problem connecting.
  72  *
  73  * \section transfer_sec Transferring data
  74  *
  75  * Once the connection is established to the server, data can start flowing.
  76  * Using the connection is very similar to the normal read() and write()
  77  * system calls. The main difference is that they're call pa_simple_read()
  78  * and pa_simple_write(). Note that these operations always block.
  79  *
  80  * \section ctrl_sec Buffer control
  81  *
  82  * If a playback stream is used then a few other operations are available:
  83  *
  84  * \li pa_simple_drain() - Will wait for all sent data to finish playing.
  85  * \li pa_simple_flush() - Will throw away all data currently in buffers.
  86  * \li pa_simple_get_playback_latency() - Will return the total latency of
  87  *                                        the playback pipeline.
  88  *
  89  * \section cleanup_sec Cleanup
  90  *
  91  * Once playback or capture is complete, the connection should be closed
  92  * and resources freed. This is done through:
  93  *
  94  * \code
  95  * pa_simple_free(s);
  96  * \endcode
  97  */
  98
  99 /** \file
 100  * A simple but limited synchronous playback and recording
 101  * API. This is a synchronous, simplified wrapper around the standard
 102  * asynchronous API. */
 103
 104 /** \example pacat-simple.c
 105  * A simple playback tool using the simple API */
 106
 107 /** \example parec-simple.c
 108  * A simple recording tool using the simple API */
 109
 110 PA_C_DECL_BEGIN
 111
 112 /** \struct pa_simple
 113  * An opaque simple connection object */
 114 typedef struct pa_simple pa_simple;
 115
 116 /** Create a new connection to the server */
 117 pa_simple* pa_simple_new(
 118     const char *server,                 /**< Server name, or NULL for default */
 119     const char *name,                   /**< A descriptive name for this client (application name, ...) */
 120     pa_stream_direction_t dir,          /**< Open this stream for recording or playback? */
 121     const char *dev,                    /**< Sink (resp. source) name, or NULL for default */
 122     const char *stream_name,            /**< A descriptive name for this client (application name, song title, ...) */
 123     const pa_sample_spec *ss,           /**< The sample type to use */
 124     const pa_channel_map *map,          /**< The channel map to use, or NULL for default */
 125     const pa_buffer_attr *attr,         /**< Buffering attributes, or NULL for default */
 126     int *error                          /**< A pointer where the error code is stored when the routine returns NULL. It is OK to pass NULL here. */
 127     );
 128
 129 /** Close and free the connection to the server. The connection objects becomes invalid when this is called. */
 130 void pa_simple_free(pa_simple *s);
 131
 132 /** Write some data to the server */
 133 int pa_simple_write(pa_simple *s, const void*data, size_t bytes, int *error);
 134
 135 /** Wait until all data already written is played by the daemon */
 136 int pa_simple_drain(pa_simple *s, int *error);
 137
 138 /** Read some data from the server */
 139 int pa_simple_read(pa_simple *s, void*data, size_t bytes, int *error);
 140
 141 /** Return the playback latency. \since 0.5 */
 142 pa_usec_t pa_simple_get_latency(pa_simple *s, int *error);
 143
 144 /** Flush the playback buffer. \since 0.5 */
 145 int pa_simple_flush(pa_simple *s, int *error);
 146
 147 PA_C_DECL_END
 148
 149 #endif