view test/testmultiaudio.c @ 2318:0c653886cce7

HandleEvent() returns done each time it is called. If done was set to 0 the program should quit, but because done is not checked until *all* events are handled a following event can reset done to 1 and prevent the program from terminating when told to. I fixed the while loop that handles events to check for the state of done after handling each event. That could leave some events unhandled when the program exits, but it ensures that the program will exit.
author Bob Pendleton <bob@pendleton.com>
date Wed, 20 Feb 2008 23:27:33 +0000
parents 9fcde304c7b6
children eec7adc3d1c5
line wrap: on
line source

#include "SDL.h"

static SDL_AudioSpec spec;
static Uint8 *sound = NULL;     /* Pointer to wave data */
static Uint32 soundlen = 0;     /* Length of wave data */

typedef struct
{
    SDL_AudioDeviceID dev;
    int soundpos;
    volatile int done;
} callback_data;

void SDLCALL
play_through_once(void *arg, Uint8 * stream, int len)
{
    callback_data *cbd = (callback_data *) arg;
    Uint8 *waveptr = sound + cbd->soundpos;
    int waveleft = soundlen - cbd->soundpos;
    int cpy = len;
    if (cpy > waveleft)
        cpy = waveleft;

    SDL_memcpy(stream, waveptr, cpy);
    len -= cpy;
    cbd->soundpos += cpy;
    if (len > 0) {
        stream += cpy;
        SDL_memset(stream, spec.silence, len);
        cbd->done++;
    }
}

static void
test_multi_audio(int devcount)
{
    callback_data cbd[64];
    int keep_going = 1;
    int i;

    if (devcount > 64) {
        fprintf(stderr, "Too many devices (%d), clamping to 64...\n",
                devcount);
        devcount = 64;
    }

    spec.callback = play_through_once;

    for (i = 0; i < devcount; i++) {
        const char *devname = SDL_GetAudioDeviceName(i, 0);
        printf("playing on device #%d: ('%s')...", i, devname);
        fflush(stdout);

        SDL_memset(&cbd[0], '\0', sizeof(callback_data));
        spec.userdata = &cbd[0];
        cbd[0].dev = SDL_OpenAudioDevice(devname, 0, &spec, NULL);
        if (cbd[0].dev == 0) {
            printf("Open device failed: %s\n", SDL_GetError());
        } else {
            SDL_PauseAudioDevice(cbd[0].dev, 0);
            while (!cbd[0].done)
                SDL_Delay(100);
            SDL_PauseAudioDevice(cbd[0].dev, 1);
            printf("done.\n");
            SDL_CloseAudioDevice(cbd[0].dev);
        }
    }

    SDL_memset(cbd, '\0', sizeof(cbd));

    printf("playing on all devices...\n");
    for (i = 0; i < devcount; i++) {
        const char *devname = SDL_GetAudioDeviceName(i, 0);
        spec.userdata = &cbd[i];
        cbd[i].dev = SDL_OpenAudioDevice(devname, 0, &spec, NULL);
        if (cbd[i].dev == 0) {
            printf("Open device %d failed: %s\n", i, SDL_GetError());
        }
    }

    for (i = 0; i < devcount; i++) {
        if (cbd[i].dev) {
            SDL_PauseAudioDevice(cbd[i].dev, 0);
        }
    }

    while (keep_going) {
        keep_going = 0;
        for (i = 0; i < devcount; i++) {
            if ((cbd[i].dev) && (!cbd[i].done)) {
                keep_going = 1;
            }
        }
        SDL_Delay(100);
    }

    for (i = 0; i < devcount; i++) {
        if (cbd[i].dev) {
            SDL_PauseAudioDevice(cbd[i].dev, 1);
            SDL_CloseAudioDevice(cbd[i].dev);
        }
    }

    printf("All done!\n");
}


int
main(int argc, char **argv)
{
    int devcount = 0;

    /* Load the SDL library */
    if (SDL_Init(SDL_INIT_AUDIO) < 0) {
        fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
        return (1);
    }

    printf("Using audio driver: %s\n", SDL_GetCurrentAudioDriver());

    devcount = SDL_GetNumAudioDevices(0);
    if (devcount < 1) {
        fprintf(stderr, "Don't see any specific audio devices!\n");
    } else {
        if (argv[1] == NULL) {
            argv[1] = "sample.wav";
        }

        /* Load the wave file into memory */
        if (SDL_LoadWAV(argv[1], &spec, &sound, &soundlen) == NULL) {
            fprintf(stderr, "Couldn't load %s: %s\n", argv[1],
                    SDL_GetError());
        } else {
            test_multi_audio(devcount);
            SDL_FreeWAV(sound);
        }
    }

    SDL_Quit();
    return 0;
}