loopwave.c
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/*
Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely.
*/
/* Program to load a wave file and loop playing it using SDL audio */
/* loopwaves.c is much more robust in handling WAVE files --
This is only for simple WAVEs
*/
#include "SDL_config.h"
#include <stdio.h>
#include <stdlib.h>
#ifdef __EMSCRIPTEN__
#include <emscripten/emscripten.h>
#endif
#include "SDL.h"
static struct
{
SDL_AudioSpec spec;
Uint8 *sound; /* Pointer to wave data */
Uint32 soundlen; /* Length of wave data */
int soundpos; /* Current play position */
} wave;
static SDL_AudioDeviceID device;
/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void
quit(int rc)
{
SDL_Quit();
exit(rc);
}
static void
close_audio()
{
if (device != 0) {
SDL_CloseAudioDevice(device);
device = 0;
}
}
static void
open_audio()
{
/* Initialize fillerup() variables */
device = SDL_OpenAudioDevice(NULL, SDL_FALSE, &wave.spec, NULL, 0);
if (!device) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open audio: %s\n", SDL_GetError());
SDL_FreeWAV(wave.sound);
quit(2);
}
/* Let the audio run */
SDL_PauseAudioDevice(device, SDL_FALSE);
}
static void reopen_audio()
{
close_audio();
open_audio();
}
void SDLCALL
fillerup(void *unused, Uint8 * stream, int len)
{
Uint8 *waveptr;
int waveleft;
/* Set up the pointers */
waveptr = wave.sound + wave.soundpos;
waveleft = wave.soundlen - wave.soundpos;
/* Go! */
while (waveleft <= len) {
SDL_memcpy(stream, waveptr, waveleft);
stream += waveleft;
len -= waveleft;
waveptr = wave.sound;
waveleft = wave.soundlen;
wave.soundpos = 0;
}
SDL_memcpy(stream, waveptr, len);
wave.soundpos += len;
}
static int done = 0;
#ifdef __EMSCRIPTEN__
void
loop()
{
if(done || (SDL_GetAudioDeviceStatus(device) != SDL_AUDIO_PLAYING))
emscripten_cancel_main_loop();
}
#endif
int
main(int argc, char *argv[])
{
int i;
char filename[4096];
/* Enable standard application logging */
SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
/* Load the SDL library */
if (SDL_Init(SDL_INIT_AUDIO|SDL_INIT_EVENTS) < 0) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
return (1);
}
if (argc > 1) {
SDL_strlcpy(filename, argv[1], sizeof(filename));
} else {
SDL_strlcpy(filename, "sample.wav", sizeof(filename));
}
/* Load the wave file into memory */
if (SDL_LoadWAV(filename, &wave.spec, &wave.sound, &wave.soundlen) == NULL) {
SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load %s: %s\n", filename, SDL_GetError());
quit(1);
}
wave.spec.callback = fillerup;
/* Show the list of available drivers */
SDL_Log("Available audio drivers:");
for (i = 0; i < SDL_GetNumAudioDrivers(); ++i) {
SDL_Log("%i: %s", i, SDL_GetAudioDriver(i));
}
SDL_Log("Using audio driver: %s\n", SDL_GetCurrentAudioDriver());
open_audio();
SDL_FlushEvents(SDL_AUDIODEVICEADDED, SDL_AUDIODEVICEREMOVED);
#ifdef __EMSCRIPTEN__
emscripten_set_main_loop(loop, 0, 1);
#else
while (!done) {
SDL_Event event;
while (SDL_PollEvent(&event) > 0) {
if (event.type == SDL_QUIT) {
done = 1;
}
if ((event.type == SDL_AUDIODEVICEADDED && !event.adevice.iscapture) ||
(event.type == SDL_AUDIODEVICEREMOVED && !event.adevice.iscapture && event.adevice.which == device)) {
reopen_audio();
}
}
SDL_Delay(100);
}
#endif
/* Clean up on signal */
close_audio();
SDL_FreeWAV(wave.sound);
SDL_Quit();
return (0);
}
/* vi: set ts=4 sw=4 expandtab: */
SDL.h
SDL_CloseAudioDevice
#define SDL_CloseAudioDevice
Definition: SDL_dynapi_overrides.h:97
sort_controllers.filename
string filename
Definition: sort_controllers.py:8
SDL_GetError
#define SDL_GetError
Definition: SDL_dynapi_overrides.h:113
wave
static struct @285 wave
Uint32
uint32_t Uint32
Definition: SDL_stdinc.h:203
SDL_PauseAudioDevice
#define SDL_PauseAudioDevice
Definition: SDL_dynapi_overrides.h:85
SDL_strlcpy
#define SDL_strlcpy
Definition: SDL_dynapi_overrides.h:394
main
int main(int argc, char *argv[])
Definition: loopwave.c:114
SDL_PollEvent
#define SDL_PollEvent
Definition: SDL_dynapi_overrides.h:122
SDL_LOG_CATEGORY_APPLICATION
@ SDL_LOG_CATEGORY_APPLICATION
Definition: SDL_log.h:66
NULL
#define NULL
Definition: begin_code.h:167
SDL_OpenAudioDevice
#define SDL_OpenAudioDevice
Definition: SDL_dynapi_overrides.h:81
SDL_INIT_EVENTS
#define SDL_INIT_EVENTS
Definition: SDL.h:83
soundlen
Uint32 soundlen
Definition: loopwave.c:33
done
static int done
Definition: loopwave.c:102
SDLCALL
#define SDLCALL
Definition: SDL_internal.h:49
stream
GLuint GLuint stream
Definition: SDL_opengl_glext.h:1776
SDL_AudioSpec
Definition: SDL_audio.h:178
sound
Uint8 * sound
Definition: loopwave.c:32
fillerup
void fillerup(void *unused, Uint8 *stream, int len)
Definition: loopwave.c:80
SDL_AUDIODEVICEADDED
@ SDL_AUDIODEVICEADDED
Definition: SDL_events.h:147
soundpos
int soundpos
Definition: loopwave.c:34
SDL_FreeWAV
#define SDL_FreeWAV
Definition: SDL_dynapi_overrides.h:87
SDL_LogError
#define SDL_LogError
Definition: SDL_dynapi_overrides.h:36
len
GLenum GLsizei len
Definition: SDL_opengl_glext.h:2926
SDL_memcpy
#define SDL_memcpy
Definition: SDL_dynapi_overrides.h:387
event
struct _cl_event * event
Definition: SDL_opengl_glext.h:2649
SDL_FALSE
@ SDL_FALSE
Definition: SDL_stdinc.h:163
loop
void loop()
Definition: checkkeys.c:152
SDL_AudioDeviceID
Uint32 SDL_AudioDeviceID
Definition: SDL_audio.h:330
open_audio
static void open_audio()
Definition: loopwave.c:57
SDL_Log
#define SDL_Log
Definition: SDL_dynapi_overrides.h:31
reopen_audio
static void reopen_audio()
Definition: loopwave.c:72
SDL_QUIT
@ SDL_QUIT
Definition: SDL_events.h:60
SDL_LoadWAV
#define SDL_LoadWAV(file, spec, audio_buf, audio_len)
Definition: SDL_audio.h:484
SDL_Quit
#define SDL_Quit
Definition: SDL_dynapi_overrides.h:58
SDL_GetAudioDeviceStatus
#define SDL_GetAudioDeviceStatus
Definition: SDL_dynapi_overrides.h:83
SDL_FlushEvents
#define SDL_FlushEvents
Definition: SDL_dynapi_overrides.h:121
SDL_Delay
#define SDL_Delay
Definition: SDL_dynapi_overrides.h:486
SDL_GetAudioDriver
#define SDL_GetAudioDriver
Definition: SDL_dynapi_overrides.h:74
SDL_GetCurrentAudioDriver
#define SDL_GetCurrentAudioDriver
Definition: SDL_dynapi_overrides.h:77
spec
SDL_AudioSpec spec
Definition: loopwave.c:31
SDL_LOG_PRIORITY_INFO
@ SDL_LOG_PRIORITY_INFO
Definition: SDL_log.h:106
SDL_LogSetPriority
#define SDL_LogSetPriority
Definition: SDL_dynapi_overrides.h:236
SDL_AUDIO_PLAYING
@ SDL_AUDIO_PLAYING
Definition: SDL_audio.h:398
quit
static void quit(int rc)
Definition: loopwave.c:41
SDL_Event
General event structure.
Definition: SDL_events.h:557
SDL_AUDIODEVICEREMOVED
@ SDL_AUDIODEVICEREMOVED
Definition: SDL_events.h:148
SDL_Init
#define SDL_Init
Definition: SDL_dynapi_overrides.h:54
close_audio
static void close_audio()
Definition: loopwave.c:48
device
static SDL_AudioDeviceID device
Definition: loopwave.c:37
i
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
SDL_GetNumAudioDrivers
#define SDL_GetNumAudioDrivers
Definition: SDL_dynapi_overrides.h:73
SDL_INIT_AUDIO
#define SDL_INIT_AUDIO
Definition: SDL.h:78
Uint8
uint8_t Uint8
Definition: SDL_stdinc.h:179