SDL 2.0
SDL_sysaudio.h
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1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
4
5 This software is provided 'as-is', without any express or implied
6 warranty. In no event will the authors be held liable for any damages
7 arising from the use of this software.
8
9 Permission is granted to anyone to use this software for any purpose,
10 including commercial applications, and to alter it and redistribute it
11 freely, subject to the following restrictions:
12
13 1. The origin of this software must not be misrepresented; you must not
14 claim that you wrote the original software. If you use this software
15 in a product, an acknowledgment in the product documentation would be
16 appreciated but is not required.
17 2. Altered source versions must be plainly marked as such, and must not be
18 misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20*/
21#include "../SDL_internal.h"
22
23#ifndef SDL_sysaudio_h_
24#define SDL_sysaudio_h_
25
26#include "SDL_mutex.h"
27#include "SDL_thread.h"
28#include "../SDL_dataqueue.h"
29#include "./SDL_audio_c.h"
30
31/* !!! FIXME: These are wordy and unlocalized... */
32#define DEFAULT_OUTPUT_DEVNAME "System audio output device"
33#define DEFAULT_INPUT_DEVNAME "System audio capture device"
34
35/* The SDL audio driver */
36typedef struct SDL_AudioDevice SDL_AudioDevice;
37#define _THIS SDL_AudioDevice *_this
38
39/* Audio targets should call this as devices are added to the system (such as
40 a USB headset being plugged in), and should also be called for
41 for every device found during DetectDevices(). */
42extern void SDL_AddAudioDevice(const int iscapture, const char *name, void *handle);
43
44/* Audio targets should call this as devices are removed, so SDL can update
45 its list of available devices. */
46extern void SDL_RemoveAudioDevice(const int iscapture, void *handle);
47
48/* Audio targets should call this if an opened audio device is lost while
49 being used. This can happen due to i/o errors, or a device being unplugged,
50 etc. If the device is totally gone, please also call SDL_RemoveAudioDevice()
51 as appropriate so SDL's list of devices is accurate. */
53
54/* This is the size of a packet when using SDL_QueueAudio(). We allocate
55 these as necessary and pool them, under the assumption that we'll
56 eventually end up with a handful that keep recycling, meeting whatever
57 the app needs. We keep packing data tightly as more arrives to avoid
58 wasting space, and if we get a giant block of data, we'll split them
59 into multiple packets behind the scenes. My expectation is that most
60 apps will have 2-3 of these in the pool. 8k should cover most needs, but
61 if this is crippling for some embedded system, we can #ifdef this.
62 The system preallocates enough packets for 2 callbacks' worth of data. */
63#define SDL_AUDIOBUFFERQUEUE_PACKETLEN (8 * 1024)
64
65typedef struct SDL_AudioDriverImpl
66{
68 int (*OpenDevice) (_THIS, void *handle, const char *devname, int iscapture);
69 void (*ThreadInit) (_THIS); /* Called by audio thread at start */
70 void (*ThreadDeinit) (_THIS); /* Called by audio thread at end */
71 void (*BeginLoopIteration)(_THIS); /* Called by audio thread at top of loop */
74 Uint8 *(*GetDeviceBuf) (_THIS);
75 int (*CaptureFromDevice) (_THIS, void *buffer, int buflen);
77 void (*PrepareToClose) (_THIS); /**< Called between run and draining wait for playback devices */
81 void (*FreeDeviceHandle) (void *handle); /**< SDL is done with handle from SDL_AddAudioDevice() */
83
84 /* !!! FIXME: add pause(), so we can optimize instead of mixing silence. */
85
86 /* Some flags to push duplicate code into the core and reduce #ifdefs. */
87 /* !!! FIXME: these should be SDL_bool */
95
96
97typedef struct SDL_AudioDeviceItem
98{
99 void *handle;
100 char *name;
105
106
107typedef struct SDL_AudioDriver
108{
109 /* * * */
110 /* The name of this audio driver */
111 const char *name;
112
113 /* * * */
114 /* The description of this audio driver */
115 const char *desc;
116
118
119 /* A mutex for device detection */
128
129
130/* Define the SDL audio driver structure */
132{
133 /* * * */
134 /* Data common to all devices */
136
137 /* The device's current audio specification */
139
140 /* The callback's expected audio specification (converted vs device's spec). */
142
143 /* Stream that converts and resamples. NULL if not needed. */
144 SDL_AudioStream *stream;
145
146 /* Current state flags */
147 SDL_atomic_t shutdown; /* true if we are signaling the play thread to end. */
148 SDL_atomic_t enabled; /* true if device is functioning and connected. */
151
152 /* Scratch buffer used in the bridge between SDL and the user callback. */
154
155 /* Size, in bytes, of work_buffer. */
157
158 /* A mutex for locking the mixing buffers */
160
161 /* A thread to feed the audio device */
164
165 /* Queued buffers (if app not using callback). */
167
168 /* * * */
169 /* Data private to this driver */
171
172 void *handle;
173};
174#undef _THIS
175
176typedef struct AudioBootStrap
177{
178 const char *name;
179 const char *desc;
180 int (*init) (SDL_AudioDriverImpl * impl);
181 int demand_only; /* 1==request explicitly, or it won't be available. */
183
184/* Not all of these are available in a given build. Use #ifdefs, etc. */
210
211#endif /* SDL_sysaudio_h_ */
212
213/* vi: set ts=4 sw=4 expandtab: */
Uint32 SDL_AudioDeviceID
Definition: SDL_audio.h:330
SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char const char SDL_SCANF_FORMAT_STRING const char return SDL_ThreadFunction const char void return Uint32 return Uint32 void
GLuint buffer
GLuint const GLchar * name
SDL_bool
Definition: SDL_stdinc.h:162
uint32_t Uint32
Definition: SDL_stdinc.h:203
uint8_t Uint8
Definition: SDL_stdinc.h:179
AudioBootStrap DSOUND_bootstrap
AudioBootStrap HAIKUAUDIO_bootstrap
AudioBootStrap SNDIO_bootstrap
AudioBootStrap PULSEAUDIO_bootstrap
AudioBootStrap ARTS_bootstrap
AudioBootStrap EMSCRIPTENAUDIO_bootstrap
AudioBootStrap JACK_bootstrap
AudioBootStrap FUSIONSOUND_bootstrap
AudioBootStrap NACLAUDIO_bootstrap
AudioBootStrap SUNAUDIO_bootstrap
#define _THIS
Definition: SDL_sysaudio.h:37
AudioBootStrap NETBSDAUDIO_bootstrap
AudioBootStrap QSAAUDIO_bootstrap
AudioBootStrap PAUDIO_bootstrap
void SDL_RemoveAudioDevice(const int iscapture, void *handle)
Definition: SDL_audio.c:531
AudioBootStrap openslES_bootstrap
AudioBootStrap ANDROIDAUDIO_bootstrap
AudioBootStrap DSP_bootstrap
AudioBootStrap PSPAUDIO_bootstrap
void SDL_AddAudioDevice(const int iscapture, const char *name, void *handle)
Definition: SDL_audio.c:469
AudioBootStrap DUMMYAUDIO_bootstrap
AudioBootStrap COREAUDIO_bootstrap
AudioBootStrap ESD_bootstrap
AudioBootStrap WASAPI_bootstrap
AudioBootStrap WINMM_bootstrap
AudioBootStrap ALSA_bootstrap
void SDL_OpenedAudioDeviceDisconnected(SDL_AudioDevice *device)
Definition: SDL_audio.c:486
AudioBootStrap NAS_bootstrap
AudioBootStrap DISKAUDIO_bootstrap
unsigned long SDL_threadID
Definition: SDL_thread.h:49
EGLImageKHR EGLint EGLint * handle
Definition: eglext.h:937
static SDL_AudioDeviceID device
Definition: loopwave.c:37
const char * name
Definition: SDL_sysaudio.h:178
const char * desc
Definition: SDL_sysaudio.h:179
int(* init)(SDL_AudioDriverImpl *impl)
Definition: SDL_sysaudio.h:180
SDL_AudioSpec callbackspec
Definition: SDL_sysaudio.h:141
Uint8 * work_buffer
Definition: SDL_sysaudio.h:153
SDL_atomic_t enabled
Definition: SDL_sysaudio.h:148
SDL_bool iscapture
Definition: SDL_sysaudio.h:150
SDL_Thread * thread
Definition: SDL_sysaudio.h:162
SDL_AudioStream * stream
Definition: SDL_sysaudio.h:144
Uint32 work_buffer_len
Definition: SDL_sysaudio.h:156
SDL_atomic_t shutdown
Definition: SDL_sysaudio.h:147
SDL_atomic_t paused
Definition: SDL_sysaudio.h:149
SDL_AudioDeviceID id
Definition: SDL_sysaudio.h:135
struct SDL_PrivateAudioData * hidden
Definition: SDL_sysaudio.h:170
SDL_DataQueue * buffer_queue
Definition: SDL_sysaudio.h:166
SDL_AudioSpec spec
Definition: SDL_sysaudio.h:138
SDL_mutex * mixer_lock
Definition: SDL_sysaudio.h:159
SDL_threadID threadid
Definition: SDL_sysaudio.h:163
struct SDL_AudioDeviceItem * next
Definition: SDL_sysaudio.h:103
SDL_AudioDeviceItem * inputDevices
Definition: SDL_sysaudio.h:126
SDL_bool captureDevicesRemoved
Definition: SDL_sysaudio.h:121
SDL_bool outputDevicesRemoved
Definition: SDL_sysaudio.h:122
const char * name
Definition: SDL_sysaudio.h:111
SDL_mutex * detectionLock
Definition: SDL_sysaudio.h:120
const char * desc
Definition: SDL_sysaudio.h:115
SDL_AudioDriverImpl impl
Definition: SDL_sysaudio.h:117
SDL_AudioDeviceItem * outputDevices
Definition: SDL_sysaudio.h:125
void(* PlayDevice)(_THIS)
Definition: SDL_sysaudio.h:73
void(* WaitDevice)(_THIS)
Definition: SDL_sysaudio.h:72
void(* CloseDevice)(_THIS)
Definition: SDL_sysaudio.h:78
void(* FlushCapture)(_THIS)
Definition: SDL_sysaudio.h:76
void(* PrepareToClose)(_THIS)
Definition: SDL_sysaudio.h:77
void(* UnlockDevice)(_THIS)
Definition: SDL_sysaudio.h:80
void(* DetectDevices)(void)
Definition: SDL_sysaudio.h:67
void(* LockDevice)(_THIS)
Definition: SDL_sysaudio.h:79
void(* ThreadDeinit)(_THIS)
Definition: SDL_sysaudio.h:70
void(* Deinitialize)(void)
Definition: SDL_sysaudio.h:82
void(* BeginLoopIteration)(_THIS)
Definition: SDL_sysaudio.h:71
void(* ThreadInit)(_THIS)
Definition: SDL_sysaudio.h:69
int(* CaptureFromDevice)(_THIS, void *buffer, int buflen)
Definition: SDL_sysaudio.h:75
void(* FreeDeviceHandle)(void *handle)
Definition: SDL_sysaudio.h:81
int(* OpenDevice)(_THIS, void *handle, const char *devname, int iscapture)
Definition: SDL_sysaudio.h:68
A type representing an atomic integer value. It is a struct so people don't accidentally use numeric ...
Definition: SDL_atomic.h:216