loopwave.c
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/* Program to load a wave file and loop playing it using SDL sound */
/* loopwaves.c is much more robust in handling WAVE files --
This is only for simple WAVEs
*/
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#include "SDL_config.h"
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#include <stdio.h>
#include <stdlib.h>
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#if HAVE_SIGNAL_H
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#include <signal.h>
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#endif
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#include "SDL.h"
#include "SDL_audio.h"
struct {
SDL_AudioSpec spec;
Uint8 *sound; /* Pointer to wave data */
Uint32 soundlen; /* Length of wave data */
int soundpos; /* Current play position */
} wave;
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/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void quit(int rc)
{
SDL_Quit();
exit(rc);
}
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void 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_MixAudio(stream, waveptr, waveleft, SDL_MIX_MAXVOLUME);
stream += waveleft;
len -= waveleft;
waveptr = wave.sound;
waveleft = wave.soundlen;
wave.soundpos = 0;
}
SDL_MixAudio(stream, waveptr, len, SDL_MIX_MAXVOLUME);
wave.soundpos += len;
}
static int done = 0;
void poked(int sig)
{
done = 1;
}
int main(int argc, char *argv[])
{
char name[32];
/* Load the SDL library */
if ( SDL_Init(SDL_INIT_AUDIO) < 0 ) {
fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
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}
if ( argv[1] == NULL ) {
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argv[1] = "sample.wav";
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}
/* Load the wave file into memory */
if ( SDL_LoadWAV(argv[1],
&wave.spec, &wave.sound, &wave.soundlen) == NULL ) {
fprintf(stderr, "Couldn't load %s: %s\n",
argv[1], SDL_GetError());
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}
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wave.spec.callback = fillerup;
#if HAVE_SIGNAL_H
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/* Set the signals */
#ifdef SIGHUP
signal(SIGHUP, poked);
#endif
signal(SIGINT, poked);
#ifdef SIGQUIT
signal(SIGQUIT, poked);
#endif
signal(SIGTERM, poked);
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#endif /* HAVE_SIGNAL_H */
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/* Initialize fillerup() variables */
if ( SDL_OpenAudio(&wave.spec, NULL) < 0 ) {
fprintf(stderr, "Couldn't open audio: %s\n", SDL_GetError());
SDL_FreeWAV(wave.sound);
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}
SDL_PauseAudio(0);
/* Let the audio run */
printf("Using audio driver: %s\n", SDL_AudioDriverName(name, 32));
while ( ! done && (SDL_GetAudioStatus() == SDL_AUDIO_PLAYING) )
SDL_Delay(1000);
/* Clean up on signal */
SDL_CloseAudio();
SDL_FreeWAV(wave.sound);
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return(0);
}