SDL  2.0
testaudiohotplug.c
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1 /*
2  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
3 
4  This software is provided 'as-is', without any express or implied
5  warranty. In no event will the authors be held liable for any damages
6  arising from the use of this software.
7 
8  Permission is granted to anyone to use this software for any purpose,
9  including commercial applications, and to alter it and redistribute it
10  freely.
11 */
12 
13 /* Program to test hotplugging of audio devices */
14 
15 #include "SDL_config.h"
16 
17 #include <stdio.h>
18 #include <stdlib.h>
19 
20 #if HAVE_SIGNAL_H
21 #include <signal.h>
22 #endif
23 
24 #ifdef __EMSCRIPTEN__
25 #include <emscripten/emscripten.h>
26 #endif
27 
28 #include "SDL.h"
29 
31 static Uint8 *sound = NULL; /* Pointer to wave data */
32 static Uint32 soundlen = 0; /* Length of wave data */
33 
34 static int posindex = 0;
35 static Uint32 positions[64];
36 
37 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
38 static void
39 quit(int rc)
40 {
41  SDL_Quit();
42  exit(rc);
43 }
44 
45 void SDLCALL
46 fillerup(void *_pos, Uint8 * stream, int len)
47 {
48  Uint32 pos = *((Uint32 *) _pos);
49  Uint8 *waveptr;
50  int waveleft;
51 
52  /* Set up the pointers */
53  waveptr = sound + pos;
54  waveleft = soundlen - pos;
55 
56  /* Go! */
57  while (waveleft <= len) {
58  SDL_memcpy(stream, waveptr, waveleft);
59  stream += waveleft;
60  len -= waveleft;
61  waveptr = sound;
62  waveleft = soundlen;
63  pos = 0;
64  }
65  SDL_memcpy(stream, waveptr, len);
66  pos += len;
67  *((Uint32 *) _pos) = pos;
68 }
69 
70 static int done = 0;
71 void
72 poked(int sig)
73 {
74  done = 1;
75 }
76 
77 static const char*
78 devtypestr(int iscapture)
79 {
80  return iscapture ? "capture" : "output";
81 }
82 
83 static void
85 {
86  SDL_Event e;
88  while (SDL_PollEvent(&e)) {
89  if (e.type == SDL_QUIT) {
90  done = 1;
91  } else if (e.type == SDL_KEYUP) {
92  if (e.key.keysym.sym == SDLK_ESCAPE)
93  done = 1;
94  } else if (e.type == SDL_AUDIODEVICEADDED) {
95  int index = e.adevice.which;
96  int iscapture = e.adevice.iscapture;
97  const char *name = SDL_GetAudioDeviceName(index, iscapture);
98  if (name != NULL)
99  SDL_Log("New %s audio device at index %u: %s\n", devtypestr(iscapture), (unsigned int) index, name);
100  else {
101  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Got new %s device at index %u, but failed to get the name: %s\n",
102  devtypestr(iscapture), (unsigned int) index, SDL_GetError());
103  continue;
104  }
105  if (!iscapture) {
106  positions[posindex] = 0;
107  spec.userdata = &positions[posindex++];
108  spec.callback = fillerup;
109  dev = SDL_OpenAudioDevice(name, 0, &spec, NULL, 0);
110  if (!dev) {
111  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open '%s': %s\n", name, SDL_GetError());
112  } else {
113  SDL_Log("Opened '%s' as %u\n", name, (unsigned int) dev);
114  SDL_PauseAudioDevice(dev, 0);
115  }
116  }
117  } else if (e.type == SDL_AUDIODEVICEREMOVED) {
118  dev = (SDL_AudioDeviceID) e.adevice.which;
119  SDL_Log("%s device %u removed.\n", devtypestr(e.adevice.iscapture), (unsigned int) dev);
121  }
122  }
123 }
124 
125 #ifdef __EMSCRIPTEN__
126 void
127 loop()
128 {
129  if(done)
130  emscripten_cancel_main_loop();
131  else
132  iteration();
133 }
134 #endif
135 
136 int
137 main(int argc, char *argv[])
138 {
139  int i;
140  char filename[4096];
141 
142  /* Enable standard application logging */
144 
145  /* Load the SDL library */
147  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
148  return (1);
149  }
150 
151  /* Some targets (Mac CoreAudio) need an event queue for audio hotplug, so make and immediately hide a window. */
153 
154  if (argc > 1) {
155  SDL_strlcpy(filename, argv[1], sizeof(filename));
156  } else {
157  SDL_strlcpy(filename, "sample.wav", sizeof(filename));
158  }
159  /* Load the wave file into memory */
160  if (SDL_LoadWAV(filename, &spec, &sound, &soundlen) == NULL) {
161  SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load %s: %s\n", filename, SDL_GetError());
162  quit(1);
163  }
164 
165 #if HAVE_SIGNAL_H
166  /* Set the signals */
167 #ifdef SIGHUP
168  signal(SIGHUP, poked);
169 #endif
170  signal(SIGINT, poked);
171 #ifdef SIGQUIT
172  signal(SIGQUIT, poked);
173 #endif
174  signal(SIGTERM, poked);
175 #endif /* HAVE_SIGNAL_H */
176 
177  /* Show the list of available drivers */
178  SDL_Log("Available audio drivers:");
179  for (i = 0; i < SDL_GetNumAudioDrivers(); ++i) {
180  SDL_Log("%i: %s", i, SDL_GetAudioDriver(i));
181  }
182 
183  SDL_Log("Select a driver with the SDL_AUDIODRIVER environment variable.\n");
184  SDL_Log("Using audio driver: %s\n", SDL_GetCurrentAudioDriver());
185 
186 #ifdef __EMSCRIPTEN__
187  emscripten_set_main_loop(loop, 0, 1);
188 #else
189  while (!done) {
190  SDL_Delay(100);
191  iteration();
192  }
193 #endif
194 
195  /* Clean up on signal */
196  /* Quit audio first, then free WAV. This prevents access violations in the audio threads. */
199  SDL_Quit();
200  return (0);
201 }
202 
203 /* vi: set ts=4 sw=4 expandtab: */
#define SDL_GetNumAudioDrivers
#define SDL_strlcpy
void loop()
Definition: checkkeys.c:152
#define SDL_PollEvent
#define SDL_GetError
#define SDL_CloseAudioDevice
#define SDL_OpenAudioDevice
static SDL_AudioSpec spec
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 SDL_AssertionHandler void SDL_SpinLock SDL_atomic_t int int return SDL_atomic_t return void void void return void return int return SDL_AudioSpec SDL_AudioSpec return int int return return int SDL_RWops int SDL_AudioSpec Uint8 Uint32 * e
static const char * devtypestr(int iscapture)
#define SDL_QuitSubSystem
void poked(int sig)
#define SDL_FreeWAV
#define SDL_CreateWindow
#define SDL_WINDOWPOS_UNDEFINED
Definition: SDL_video.h:130
uint32_t Uint32
Definition: SDL_stdinc.h:181
#define SDL_MinimizeWindow
static void quit(int rc)
GLenum GLsizei len
GLuint const GLchar * name
static void iteration()
#define SDL_LogError
static Uint8 * sound
#define SDL_GetAudioDeviceName
#define SDL_Log
#define SDL_memcpy
static int posindex
GLuint GLuint stream
uint8_t Uint8
Definition: SDL_stdinc.h:157
#define SDL_Quit
#define SDL_LoadWAV(file, spec, audio_buf, audio_len)
Definition: SDL_audio.h:450
static Uint32 positions[64]
#define SDL_GetAudioDriver
SDL_Keysym keysym
Definition: SDL_events.h:199
static Uint32 soundlen
SDL_AudioCallback callback
Definition: SDL_audio.h:186
int main(int argc, char *argv[])
GLuint index
#define SDL_Delay
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50
#define SDL_LogSetPriority
#define SDL_GetCurrentAudioDriver
#define NULL
Definition: begin_code.h:164
SDL_AudioDeviceEvent adevice
Definition: SDL_events.h:544
#define SDL_INIT_AUDIO
Definition: SDL.h:77
SDL_KeyboardEvent key
Definition: SDL_events.h:530
Uint32 SDL_AudioDeviceID
Definition: SDL_audio.h:329
void fillerup(void *_pos, Uint8 *stream, int len)
SDL_Keycode sym
Definition: SDL_keyboard.h:50
void * userdata
Definition: SDL_audio.h:187
#define SDL_Init
General event structure.
Definition: SDL_events.h:525
static int done
#define SDLCALL
Definition: SDL_internal.h:45
#define SDL_INIT_VIDEO
Definition: SDL.h:78
Uint32 type
Definition: SDL_events.h:527
#define SDL_PauseAudioDevice