/* Copyright (C) 1997-2018 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 sound queueing */ #include <stdio.h> #include <stdlib.h> #ifdef __EMSCRIPTEN__ #include <emscripten/emscripten.h> #endif #include "SDL.h" #if HAVE_SIGNAL_H #include <signal.h> #endif static struct { SDL_AudioSpec spec; Uint8 *sound; /* Pointer to wave data */ Uint32 soundlen; /* Length of wave data */ } wave; /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */ static void quit(int rc) { SDL_Quit(); exit(rc); } static int done = 0; void poked(int sig) { done = 1; } void loop() { #ifdef __EMSCRIPTEN__ if (done || (SDL_GetAudioStatus() != SDL_AUDIO_PLAYING)) { emscripten_cancel_main_loop(); } else #endif { /* The device from SDL_OpenAudio() is always device #1. */ const Uint32 queued = SDL_GetQueuedAudioSize(1); SDL_Log("Device has %u bytes queued.\n", (unsigned int) queued); if (queued <= 8192) { /* time to requeue the whole thing? */ if (SDL_QueueAudio(1, wave.sound, wave.soundlen) == 0) { SDL_Log("Device queued %u more bytes.\n", (unsigned int) wave.soundlen); } else { SDL_Log("Device FAILED to queue %u more bytes: %s\n", (unsigned int) wave.soundlen, SDL_GetError()); } } } } int main(int argc, char *argv[]) { 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) < 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 = NULL; /* we'll push audio. */ #if HAVE_SIGNAL_H /* Set the signals */ #ifdef SIGHUP signal(SIGHUP, poked); #endif signal(SIGINT, poked); #ifdef SIGQUIT signal(SIGQUIT, poked); #endif signal(SIGTERM, poked); #endif /* HAVE_SIGNAL_H */ /* Initialize fillerup() variables */ if (SDL_OpenAudio(&wave.spec, NULL) < 0) { SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open audio: %s\n", SDL_GetError()); SDL_FreeWAV(wave.sound); quit(2); } /*static x[99999]; SDL_QueueAudio(1, x, sizeof (x));*/ /* Let the audio run */ SDL_PauseAudio(0); done = 0; /* Note that we stuff the entire audio buffer into the queue in one shot. Most apps would want to feed it a little at a time, as it plays, but we're going for simplicity here. */ #ifdef __EMSCRIPTEN__ emscripten_set_main_loop(loop, 0, 1); #else while (!done && (SDL_GetAudioStatus() == SDL_AUDIO_PLAYING)) { loop(); SDL_Delay(100); /* let it play for awhile. */ } #endif /* Clean up on signal */ SDL_CloseAudio(); SDL_FreeWAV(wave.sound); SDL_Quit(); return 0; } /* vi: set ts=4 sw=4 expandtab: */