src/audio/SDL_sysaudio.h
author Philipp Wiesemann <philipp.wiesemann@arcor.de>
Sun, 22 Feb 2015 23:21:32 +0100
changeset 9373 679eb3986e37
parent 9031 e963a13a720c
child 9391 3a54985e999e
permissions -rw-r--r--
Emscripten: Fixed out of range joystick device index after joystick disconnect.

After disconnecting a joystick the remaining kept their original device index.
This was not correct because the device index must be a number between 0 and
SDL_NumJoysticks(). It was fixed with ideas from SDL's joystick implementation
for Android. Some range checks were removed as the caller already checks them.
slouken@0
     1
/*
slouken@5535
     2
  Simple DirectMedia Layer
slouken@8149
     3
  Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
slouken@0
     4
slouken@5535
     5
  This software is provided 'as-is', without any express or implied
slouken@5535
     6
  warranty.  In no event will the authors be held liable for any damages
slouken@5535
     7
  arising from the use of this software.
slouken@0
     8
slouken@5535
     9
  Permission is granted to anyone to use this software for any purpose,
slouken@5535
    10
  including commercial applications, and to alter it and redistribute it
slouken@5535
    11
  freely, subject to the following restrictions:
slouken@0
    12
slouken@5535
    13
  1. The origin of this software must not be misrepresented; you must not
slouken@5535
    14
     claim that you wrote the original software. If you use this software
slouken@5535
    15
     in a product, an acknowledgment in the product documentation would be
slouken@5535
    16
     appreciated but is not required.
slouken@5535
    17
  2. Altered source versions must be plainly marked as such, and must not be
slouken@5535
    18
     misrepresented as being the original software.
slouken@5535
    19
  3. This notice may not be removed or altered from any source distribution.
slouken@0
    20
*/
icculus@8093
    21
#include "../SDL_internal.h"
slouken@0
    22
slouken@0
    23
#ifndef _SDL_sysaudio_h
slouken@0
    24
#define _SDL_sysaudio_h
slouken@0
    25
slouken@0
    26
#include "SDL_mutex.h"
slouken@0
    27
#include "SDL_thread.h"
slouken@0
    28
slouken@0
    29
/* The SDL audio driver */
slouken@0
    30
typedef struct SDL_AudioDevice SDL_AudioDevice;
slouken@7191
    31
#define _THIS   SDL_AudioDevice *_this
slouken@0
    32
icculus@5593
    33
/* Used by audio targets during DetectDevices() */
icculus@5593
    34
typedef void (*SDL_AddAudioDevice)(const char *name);
icculus@5593
    35
icculus@9012
    36
/* This is the size of a packet when using SDL_QueueAudio(). We allocate
icculus@9012
    37
   these as necessary and pool them, under the assumption that we'll
icculus@9012
    38
   eventually end up with a handful that keep recycling, meeting whatever
icculus@9012
    39
   the app needs. We keep packing data tightly as more arrives to avoid
icculus@9012
    40
   wasting space, and if we get a giant block of data, we'll split them
icculus@9012
    41
   into multiple packets behind the scenes. My expectation is that most
icculus@9012
    42
   apps will have 2-3 of these in the pool. 8k should cover most needs, but
icculus@9012
    43
   if this is crippling for some embedded system, we can #ifdef this.
icculus@9012
    44
   The system preallocates enough packets for 2 callbacks' worth of data. */
icculus@9012
    45
#define SDL_AUDIOBUFFERQUEUE_PACKETLEN (8 * 1024)
icculus@9012
    46
icculus@9012
    47
/* Used by apps that queue audio instead of using the callback. */
icculus@9012
    48
typedef struct SDL_AudioBufferQueue
icculus@9012
    49
{
icculus@9012
    50
    Uint8 data[SDL_AUDIOBUFFERQUEUE_PACKETLEN];  /* packet data. */
icculus@9012
    51
    Uint32 datalen;  /* bytes currently in use in this packet. */
icculus@9012
    52
    Uint32 startpos;  /* bytes currently consumed in this packet. */
icculus@9012
    53
    struct SDL_AudioBufferQueue *next;  /* next item in linked list. */
icculus@9012
    54
} SDL_AudioBufferQueue;
icculus@9012
    55
icculus@2049
    56
typedef struct SDL_AudioDriverImpl
icculus@2049
    57
{
icculus@5593
    58
    void (*DetectDevices) (int iscapture, SDL_AddAudioDevice addfn);
icculus@2049
    59
    int (*OpenDevice) (_THIS, const char *devname, int iscapture);
icculus@2049
    60
    void (*ThreadInit) (_THIS); /* Called by audio thread at start */
icculus@2049
    61
    void (*WaitDevice) (_THIS);
icculus@2049
    62
    void (*PlayDevice) (_THIS);
icculus@9031
    63
    int (*GetPendingBytes) (_THIS);
icculus@2049
    64
    Uint8 *(*GetDeviceBuf) (_THIS);
icculus@2049
    65
    void (*WaitDone) (_THIS);
icculus@2049
    66
    void (*CloseDevice) (_THIS);
icculus@2049
    67
    void (*LockDevice) (_THIS);
icculus@2049
    68
    void (*UnlockDevice) (_THIS);
icculus@2049
    69
    void (*Deinitialize) (void);
icculus@2049
    70
icculus@5590
    71
    /* !!! FIXME: add pause(), so we can optimize instead of mixing silence. */
icculus@5590
    72
icculus@2049
    73
    /* Some flags to push duplicate code into the core and reduce #ifdefs. */
icculus@5589
    74
    int ProvidesOwnCallbackThread;
icculus@5590
    75
    int SkipMixerLock;  /* !!! FIXME: do we need this anymore? */
icculus@5589
    76
    int HasCaptureSupport;
icculus@5589
    77
    int OnlyHasDefaultOutputDevice;
icculus@5589
    78
    int OnlyHasDefaultInputDevice;
icculus@2049
    79
} SDL_AudioDriverImpl;
icculus@2049
    80
icculus@2049
    81
icculus@2049
    82
typedef struct SDL_AudioDriver
slouken@1895
    83
{
slouken@1895
    84
    /* * * */
slouken@1895
    85
    /* The name of this audio driver */
slouken@1895
    86
    const char *name;
slouken@0
    87
slouken@1895
    88
    /* * * */
slouken@1895
    89
    /* The description of this audio driver */
slouken@1895
    90
    const char *desc;
slouken@0
    91
icculus@2049
    92
    SDL_AudioDriverImpl impl;
icculus@5593
    93
icculus@5593
    94
    char **outputDevices;
icculus@5593
    95
    int outputDeviceCount;
icculus@5593
    96
icculus@5593
    97
    char **inputDevices;
icculus@5593
    98
    int inputDeviceCount;
icculus@2049
    99
} SDL_AudioDriver;
slouken@0
   100
slouken@322
   101
slouken@2716
   102
/* Streamer */
slouken@2716
   103
typedef struct
slouken@2716
   104
{
slouken@2716
   105
    Uint8 *buffer;
slouken@2716
   106
    int max_len;                /* the maximum length in bytes */
slouken@2716
   107
    int read_pos, write_pos;    /* the position of the write and read heads in bytes */
slouken@2716
   108
} SDL_AudioStreamer;
slouken@2716
   109
slouken@2716
   110
icculus@2049
   111
/* Define the SDL audio driver structure */
icculus@2049
   112
struct SDL_AudioDevice
icculus@2049
   113
{
slouken@1895
   114
    /* * * */
slouken@1895
   115
    /* Data common to all devices */
slouken@0
   116
slouken@1895
   117
    /* The current audio specification (shared with audio thread) */
slouken@1895
   118
    SDL_AudioSpec spec;
slouken@0
   119
slouken@1895
   120
    /* An audio conversion block for audio format emulation */
slouken@1895
   121
    SDL_AudioCVT convert;
slouken@0
   122
slouken@2716
   123
    /* The streamer, if sample rate conversion necessitates it */
slouken@2716
   124
    int use_streamer;
slouken@2716
   125
    SDL_AudioStreamer streamer;
slouken@2716
   126
slouken@1895
   127
    /* Current state flags */
icculus@2049
   128
    int iscapture;
slouken@1895
   129
    int enabled;
slouken@1895
   130
    int paused;
slouken@1895
   131
    int opened;
slouken@0
   132
slouken@1895
   133
    /* Fake audio buffer for when the audio hardware is busy */
slouken@1895
   134
    Uint8 *fake_stream;
slouken@0
   135
slouken@1895
   136
    /* A semaphore for locking the mixing buffers */
slouken@1895
   137
    SDL_mutex *mixer_lock;
slouken@0
   138
slouken@1895
   139
    /* A thread to feed the audio device */
slouken@1895
   140
    SDL_Thread *thread;
slouken@3578
   141
    SDL_threadID threadid;
slouken@0
   142
icculus@9012
   143
    /* Queued buffers (if app not using callback). */
icculus@9012
   144
    SDL_AudioBufferQueue *buffer_queue_head; /* device fed from here. */
icculus@9012
   145
    SDL_AudioBufferQueue *buffer_queue_tail; /* queue fills to here. */
icculus@9012
   146
    SDL_AudioBufferQueue *buffer_queue_pool; /* these are unused packets. */
icculus@9012
   147
    Uint32 queued_bytes;  /* number of bytes of audio data in the queue. */
icculus@9012
   148
slouken@1895
   149
    /* * * */
slouken@1895
   150
    /* Data private to this driver */
slouken@1895
   151
    struct SDL_PrivateAudioData *hidden;
slouken@0
   152
};
slouken@0
   153
#undef _THIS
slouken@0
   154
slouken@1895
   155
typedef struct AudioBootStrap
slouken@1895
   156
{
slouken@1895
   157
    const char *name;
slouken@1895
   158
    const char *desc;
slouken@2060
   159
    int (*init) (SDL_AudioDriverImpl * impl);
icculus@5578
   160
    int demand_only;  /* 1==request explicitly, or it won't be available. */
slouken@0
   161
} AudioBootStrap;
slouken@0
   162
icculus@2049
   163
#endif /* _SDL_sysaudio_h */
slouken@0
   164
slouken@1895
   165
/* vi: set ts=4 sw=4 expandtab: */