SDL  2.0
SDL_sysaudio.h
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1 /*
2  Simple DirectMedia Layer
3  Copyright (C) 1997-2018 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 */
36 typedef 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(). */
42 extern 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. */
46 extern 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 
65 typedef 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 */
75  Uint8 *(*GetDeviceBuf) (_THIS);
76  int (*CaptureFromDevice) (_THIS, void *buffer, int buflen);
78  void (*PrepareToClose) (_THIS); /**< Called between run and draining wait for playback devices */
82  void (*FreeDeviceHandle) (void *handle); /**< SDL is done with handle from SDL_AddAudioDevice() */
84 
85  /* !!! FIXME: add pause(), so we can optimize instead of mixing silence. */
86 
87  /* Some flags to push duplicate code into the core and reduce #ifdefs. */
88  /* !!! FIXME: these should be SDL_bool */
96 
97 
98 typedef struct SDL_AudioDeviceItem
99 {
100  void *handle;
101  char *name;
103  int dupenum;
106 
107 
108 typedef struct SDL_AudioDriver
109 {
110  /* * * */
111  /* The name of this audio driver */
112  const char *name;
113 
114  /* * * */
115  /* The description of this audio driver */
116  const char *desc;
117 
119 
120  /* A mutex for device detection */
129 
130 
131 /* Define the SDL audio driver structure */
133 {
134  /* * * */
135  /* Data common to all devices */
137 
138  /* The device's current audio specification */
140 
141  /* The callback's expected audio specification (converted vs device's spec). */
143 
144  /* Stream that converts and resamples. NULL if not needed. */
145  SDL_AudioStream *stream;
146 
147  /* Current state flags */
148  SDL_atomic_t shutdown; /* true if we are signaling the play thread to end. */
149  SDL_atomic_t enabled; /* true if device is functioning and connected. */
152 
153  /* Scratch buffer used in the bridge between SDL and the user callback. */
155 
156  /* Size, in bytes, of work_buffer. */
158 
159  /* A mutex for locking the mixing buffers */
161 
162  /* A thread to feed the audio device */
165 
166  /* Queued buffers (if app not using callback). */
168 
169  /* * * */
170  /* Data private to this driver */
172 
173  void *handle;
174 };
175 #undef _THIS
176 
177 typedef struct AudioBootStrap
178 {
179  const char *name;
180  const char *desc;
181  int (*init) (SDL_AudioDriverImpl * impl);
182  int demand_only; /* 1==request explicitly, or it won't be available. */
184 
185 /* 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: */
struct SDL_PrivateAudioData * hidden
Definition: SDL_sysaudio.h:171
AudioBootStrap DSP_bootstrap
AudioBootStrap EMSCRIPTENAUDIO_bootstrap
SDL_AudioDeviceID id
Definition: SDL_sysaudio.h:136
SDL_mutex * mixer_lock
Definition: SDL_sysaudio.h:160
AudioBootStrap NAS_bootstrap
SDL_bool captureDevicesRemoved
Definition: SDL_sysaudio.h:122
SDL_atomic_t enabled
Definition: SDL_sysaudio.h:149
const char * name
Definition: SDL_sysaudio.h:112
void(* DetectDevices)(void)
Definition: SDL_sysaudio.h:67
const char * name
Definition: SDL_sysaudio.h:179
A type representing an atomic integer value. It is a struct so people don&#39;t accidentally use numeric ...
Definition: SDL_atomic.h:198
struct SDL_AudioDeviceItem * next
Definition: SDL_sysaudio.h:104
SDL_atomic_t paused
Definition: SDL_sysaudio.h:150
SDL_atomic_t shutdown
Definition: SDL_sysaudio.h:148
AudioBootStrap DISKAUDIO_bootstrap
AudioBootStrap ESD_bootstrap
void(* ThreadDeinit)(_THIS)
Definition: SDL_sysaudio.h:70
SDL_threadID threadid
Definition: SDL_sysaudio.h:164
AudioBootStrap PSPAUDIO_bootstrap
void(* PlayDevice)(_THIS)
Definition: SDL_sysaudio.h:73
void(* WaitDevice)(_THIS)
Definition: SDL_sysaudio.h:72
AudioBootStrap DUMMYAUDIO_bootstrap
SDL_AudioSpec spec
Definition: SDL_sysaudio.h:139
void SDL_AddAudioDevice(const int iscapture, const char *name, void *handle)
Definition: SDL_audio.c:473
AudioBootStrap COREAUDIO_bootstrap
AudioBootStrap SNDIO_bootstrap
AudioBootStrap HAIKUAUDIO_bootstrap
void(* UnlockDevice)(_THIS)
Definition: SDL_sysaudio.h:81
Uint32 work_buffer_len
Definition: SDL_sysaudio.h:157
GLuint const GLchar * name
SDL_mutex * detectionLock
Definition: SDL_sysaudio.h:121
AudioBootStrap SUNAUDIO_bootstrap
void SDL_RemoveAudioDevice(const int iscapture, void *handle)
Definition: SDL_audio.c:535
static SDL_AudioDeviceID device
Definition: loopwave.c:37
void(* ThreadInit)(_THIS)
Definition: SDL_sysaudio.h:69
EGLImageKHR EGLint EGLint * handle
Definition: eglext.h:937
AudioBootStrap FUSIONSOUND_bootstrap
AudioBootStrap WASAPI_bootstrap
uint8_t Uint8
Definition: SDL_stdinc.h:179
const char * desc
Definition: SDL_sysaudio.h:116
void(* PrepareToClose)(_THIS)
Definition: SDL_sysaudio.h:78
SDL_bool iscapture
Definition: SDL_sysaudio.h:151
AudioBootStrap QSAAUDIO_bootstrap
void(* Deinitialize)(void)
Definition: SDL_sysaudio.h:83
#define _THIS
Definition: SDL_sysaudio.h:37
void(* LockDevice)(_THIS)
Definition: SDL_sysaudio.h:80
SDL_AudioDeviceItem * outputDevices
Definition: SDL_sysaudio.h:126
AudioBootStrap ANDROIDAUDIO_bootstrap
AudioBootStrap WINMM_bootstrap
AudioBootStrap ALSA_bootstrap
int(* OpenDevice)(_THIS, void *handle, const char *devname, int iscapture)
Definition: SDL_sysaudio.h:68
SDL_bool
Definition: SDL_stdinc.h:161
GLuint buffer
SDL_DataQueue * buffer_queue
Definition: SDL_sysaudio.h:167
SDL_bool outputDevicesRemoved
Definition: SDL_sysaudio.h:123
int(* CaptureFromDevice)(_THIS, void *buffer, int buflen)
Definition: SDL_sysaudio.h:76
void(* CloseDevice)(_THIS)
Definition: SDL_sysaudio.h:79
SDL_AudioDriverImpl impl
Definition: SDL_sysaudio.h:118
void(* FreeDeviceHandle)(void *handle)
Definition: SDL_sysaudio.h:82
Uint32 SDL_AudioDeviceID
Definition: SDL_audio.h:330
void(* FlushCapture)(_THIS)
Definition: SDL_sysaudio.h:77
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
set set set set set set set macro pixldst1 abits if abits op else op endif endm macro pixldst2 abits if abits op else op endif endm macro pixldst4 abits if abits op else op endif endm macro pixldst0 abits op endm macro pixldst3 mem_operand op endm macro pixldst30 mem_operand op endm macro pixldst abits if abits elseif abits elseif abits elseif abits elseif abits pixldst0 abits else pixldst0 abits pixldst0 abits pixldst0 abits pixldst0 abits endif elseif abits else pixldst0 abits pixldst0 abits endif elseif abits else error unsupported bpp *numpix else pixst endif endm macro pixld1_s mem_operand if asr adds SRC_WIDTH_FIXED bpl add asl mov asr adds SRC_WIDTH_FIXED bpl add asl mov asr adds SRC_WIDTH_FIXED bpl add asl mov asr adds SRC_WIDTH_FIXED bpl add asl elseif asr adds SRC_WIDTH_FIXED bpl add asl mov asr adds SRC_WIDTH_FIXED bpl add asl else error unsupported endif endm macro pixld2_s mem_operand if mov asr add asl add asl mov asr sub UNIT_X add asl mov asr add asl add asl mov asr add UNIT_X add asl else pixld1_s mem_operand pixld1_s mem_operand endif endm macro pixld0_s mem_operand if asr adds SRC_WIDTH_FIXED bpl add asl elseif asr adds SRC_WIDTH_FIXED bpl add asl endif endm macro pixld_s_internal mem_operand if mem_operand pixld2_s mem_operand pixdeinterleave basereg elseif mem_operand elseif mem_operand elseif mem_operand elseif mem_operand pixld0_s mem_operand else pixld0_s mem_operand pixld0_s mem_operand pixld0_s mem_operand pixld0_s mem_operand endif elseif mem_operand else pixld0_s mem_operand pixld0_s mem_operand endif elseif mem_operand else error unsupported mem_operand if bpp mem_operand endif endm macro vuzp8 reg2 vuzp d d &reg2 endm macro vzip8 reg2 vzip d d &reg2 endm macro pixdeinterleave basereg basereg basereg basereg basereg endif endm macro pixinterleave basereg basereg basereg basereg basereg endif endm macro PF boost_increment endif if endif PF tst PF addne PF subne PF cmp ORIG_W if endif if endif if endif PF subge ORIG_W PF subges if endif if endif if endif endif endm macro cache_preload_simple endif if dst_r_bpp pld [DST_R, #(PREFETCH_DISTANCE_SIMPLE *dst_r_bpp/8)] endif if mask_bpp pld init[MASK, #(PREFETCH_DISTANCE_SIMPLE *mask_bpp/8)] endif endif endm macro fetch_mask_pixblock pixld mask_basereg pixblock_size MASK endm macro ensure_destination_ptr_alignment process_pixblock_tail_head if beq irp local skip1 beq endif SRC MASK if dst_r_bpp DST_R else add endif PF add sub src_basereg pixdeinterleave mask_basereg pixdeinterleave dst_r_basereg process_pixblock_head pixblock_size cache_preload_simple process_pixblock_tail pixinterleave dst_w_basereg irp beq endif process_pixblock_tail_head tst beq irp if pixblock_size chunk_size tst beq pixld_src SRC pixld MASK if DST_R else pixld DST_R endif if src_basereg pixdeinterleave mask_basereg pixdeinterleave dst_r_basereg process_pixblock_head if pixblock_size cache_preload_simple endif process_pixblock_tail pixinterleave dst_w_basereg irp if pixblock_size chunk_size tst beq if DST_W else pixst DST_W else mov ORIG_W endif add lsl if lsl endif if lsl endif lsl endif lsl endif lsl endif subs mov DST_W if regs_shortage str endif bge start_of_loop_label endm macro generate_composite_function
uint32_t Uint32
Definition: SDL_stdinc.h:203
AudioBootStrap PAUDIO_bootstrap
AudioBootStrap NACLAUDIO_bootstrap
AudioBootStrap NETBSDAUDIO_bootstrap
AudioBootStrap JACK_bootstrap
AudioBootStrap ARTS_bootstrap
void SDL_OpenedAudioDeviceDisconnected(SDL_AudioDevice *device)
Definition: SDL_audio.c:490
void(* BeginLoopIteration)(_THIS)
Definition: SDL_sysaudio.h:71
AudioBootStrap DSOUND_bootstrap
AudioBootStrap PULSEAUDIO_bootstrap
int(* GetPendingBytes)(_THIS)
Definition: SDL_sysaudio.h:74
const char * desc
Definition: SDL_sysaudio.h:180
SDL_Thread * thread
Definition: SDL_sysaudio.h:163
SDL_AudioSpec callbackspec
Definition: SDL_sysaudio.h:142
SDL_AudioStream * stream
Definition: SDL_sysaudio.h:145
SDL_AudioDeviceItem * inputDevices
Definition: SDL_sysaudio.h:127
Uint8 * work_buffer
Definition: SDL_sysaudio.h:154
unsigned long SDL_threadID
Definition: SDL_thread.h:49