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

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