test/loopwavequeue.c
author Sam Lantinga <slouken@libsdl.org>
Thu, 23 May 2019 14:19:00 -0700
changeset 12756 4116bf232fe7
parent 12503 806492103856
permissions -rw-r--r--
Added a function to get the current Android SDK version at runtime
     1 /*
     2   Copyright (C) 1997-2019 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 load a wave file and loop playing it using SDL sound queueing */
    14 
    15 #include <stdio.h>
    16 #include <stdlib.h>
    17 
    18 #ifdef __EMSCRIPTEN__
    19 #include <emscripten/emscripten.h>
    20 #endif
    21 
    22 #include "SDL.h"
    23 
    24 #if HAVE_SIGNAL_H
    25 #include <signal.h>
    26 #endif
    27 
    28 static struct
    29 {
    30     SDL_AudioSpec spec;
    31     Uint8 *sound;               /* Pointer to wave data */
    32     Uint32 soundlen;            /* Length of wave data */
    33 } wave;
    34 
    35 
    36 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
    37 static void
    38 quit(int rc)
    39 {
    40     SDL_Quit();
    41     exit(rc);
    42 }
    43 
    44 static int done = 0;
    45 void
    46 poked(int sig)
    47 {
    48     done = 1;
    49 }
    50 
    51 void
    52 loop()
    53 {
    54 #ifdef __EMSCRIPTEN__
    55     if (done || (SDL_GetAudioStatus() != SDL_AUDIO_PLAYING)) {
    56         emscripten_cancel_main_loop();
    57     }
    58     else
    59 #endif
    60     {
    61         /* The device from SDL_OpenAudio() is always device #1. */
    62         const Uint32 queued = SDL_GetQueuedAudioSize(1);
    63         SDL_Log("Device has %u bytes queued.\n", (unsigned int) queued);
    64         if (queued <= 8192) {  /* time to requeue the whole thing? */
    65             if (SDL_QueueAudio(1, wave.sound, wave.soundlen) == 0) {
    66                 SDL_Log("Device queued %u more bytes.\n", (unsigned int) wave.soundlen);
    67             } else {
    68                 SDL_Log("Device FAILED to queue %u more bytes: %s\n", (unsigned int) wave.soundlen, SDL_GetError());
    69             }
    70         }
    71     }
    72 }
    73 
    74 int
    75 main(int argc, char *argv[])
    76 {
    77     char filename[4096];
    78 
    79     /* Enable standard application logging */
    80     SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);
    81 
    82     /* Load the SDL library */
    83     if (SDL_Init(SDL_INIT_AUDIO) < 0) {
    84         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());
    85         return (1);
    86     }
    87 
    88     if (argc > 1) {
    89         SDL_strlcpy(filename, argv[1], sizeof(filename));
    90     } else {
    91         SDL_strlcpy(filename, "sample.wav", sizeof(filename));
    92     }
    93     /* Load the wave file into memory */
    94     if (SDL_LoadWAV(filename, &wave.spec, &wave.sound, &wave.soundlen) == NULL) {
    95         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't load %s: %s\n", filename, SDL_GetError());
    96         quit(1);
    97     }
    98 
    99     wave.spec.callback = NULL;  /* we'll push audio. */
   100 
   101 #if HAVE_SIGNAL_H
   102     /* Set the signals */
   103 #ifdef SIGHUP
   104     signal(SIGHUP, poked);
   105 #endif
   106     signal(SIGINT, poked);
   107 #ifdef SIGQUIT
   108     signal(SIGQUIT, poked);
   109 #endif
   110     signal(SIGTERM, poked);
   111 #endif /* HAVE_SIGNAL_H */
   112 
   113     /* Initialize fillerup() variables */
   114     if (SDL_OpenAudio(&wave.spec, NULL) < 0) {
   115         SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open audio: %s\n", SDL_GetError());
   116         SDL_FreeWAV(wave.sound);
   117         quit(2);
   118     }
   119 
   120     /*static x[99999]; SDL_QueueAudio(1, x, sizeof (x));*/
   121 
   122     /* Let the audio run */
   123     SDL_PauseAudio(0);
   124 
   125     done = 0;
   126 
   127     /* Note that we stuff the entire audio buffer into the queue in one
   128        shot. Most apps would want to feed it a little at a time, as it
   129        plays, but we're going for simplicity here. */
   130     
   131 #ifdef __EMSCRIPTEN__
   132     emscripten_set_main_loop(loop, 0, 1);
   133 #else
   134     while (!done && (SDL_GetAudioStatus() == SDL_AUDIO_PLAYING))
   135     {
   136         loop();
   137 
   138         SDL_Delay(100);  /* let it play for awhile. */
   139     }
   140 #endif
   141 
   142     /* Clean up on signal */
   143     SDL_CloseAudio();
   144     SDL_FreeWAV(wave.sound);
   145     SDL_Quit();
   146     return 0;
   147 }
   148 
   149 /* vi: set ts=4 sw=4 expandtab: */