view src/audio/SDL_audiodev.c @ 3794:db24e43972ac SDL-ryan-multiple-audio-device

Test program to play audio to every available device, one at a time, then all at once.
author Ryan C. Gordon <icculus@icculus.org>
date Tue, 03 Oct 2006 23:45:36 +0000
parents c121d94672cb
children 5f6550e5184f 7852b5b78af5
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* Get the name of the audio device we use for output */

#if SDL_AUDIO_DRIVER_BSD || SDL_AUDIO_DRIVER_OSS || SDL_AUDIO_DRIVER_SUNAUDIO

#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>

#include "SDL_stdinc.h"
#include "SDL_audiodev_c.h"

#ifndef _PATH_DEV_DSP
#if defined(__NETBSD__) || defined(__OPENBSD__)
#define _PATH_DEV_DSP  "/dev/audio"
#else
#define _PATH_DEV_DSP  "/dev/dsp"
#endif
#endif
#ifndef _PATH_DEV_DSP24
#define _PATH_DEV_DSP24	"/dev/sound/dsp"
#endif
#ifndef _PATH_DEV_AUDIO
#define _PATH_DEV_AUDIO	"/dev/audio"
#endif


int
SDL_OpenAudioPath(char *path, int maxlen, int flags, int classic)
{
    const char *audiodev;
    int audio_fd;
    char audiopath[1024];

    /* Figure out what our audio device is */
    if (((audiodev = SDL_getenv("SDL_PATH_DSP")) == NULL) &&
        ((audiodev = SDL_getenv("AUDIODEV")) == NULL)) {
        if (classic) {
            audiodev = _PATH_DEV_AUDIO;
        } else {
            struct stat sb;

            /* Added support for /dev/sound/\* in Linux 2.4 */
            if (((stat("/dev/sound", &sb) == 0) && S_ISDIR(sb.st_mode))
                && ((stat(_PATH_DEV_DSP24, &sb) == 0)
                    && S_ISCHR(sb.st_mode))) {
                audiodev = _PATH_DEV_DSP24;
            } else {
                audiodev = _PATH_DEV_DSP;
            }
        }
    }
    audio_fd = open(audiodev, flags, 0);

    /* If the first open fails, look for other devices */
    if ((audio_fd < 0) && (SDL_strlen(audiodev) < (sizeof(audiopath) - 3))) {
        int exists, instance;
        struct stat sb;

        instance = 1;
        do {                    /* Don't use errno ENOENT - it may not be thread-safe */
            SDL_snprintf(audiopath, SDL_arraysize(audiopath),
                         "%s%d", audiodev, instance++);
            exists = 0;
            if (stat(audiopath, &sb) == 0) {
                exists = 1;
                audio_fd = open(audiopath, flags, 0);
            }
        }
        while (exists && (audio_fd < 0));
        audiodev = audiopath;
    }
    if (path != NULL) {
        SDL_strlcpy(path, audiodev, maxlen);
        path[maxlen - 1] = '\0';
    }
    return (audio_fd);
}

#elif SDL_AUDIO_DRIVER_PAUD

/* Get the name of the audio device we use for output */

#include <sys/types.h>
#include <sys/stat.h>

#include "SDL_stdinc.h"
#include "SDL_audiodev_c.h"

#ifndef _PATH_DEV_DSP
#define _PATH_DEV_DSP	"/dev/%caud%c/%c"
#endif

char devsettings[][3] = {
    {'p', '0', '1'}, {'p', '0', '2'}, {'p', '0', '3'}, {'p', '0', '4'},
    {'p', '1', '1'}, {'p', '1', '2'}, {'p', '1', '3'}, {'p', '1', '4'},
    {'p', '2', '1'}, {'p', '2', '2'}, {'p', '2', '3'}, {'p', '2', '4'},
    {'p', '3', '1'}, {'p', '3', '2'}, {'p', '3', '3'}, {'p', '3', '4'},
    {'b', '0', '1'}, {'b', '0', '2'}, {'b', '0', '3'}, {'b', '0', '4'},
    {'b', '1', '1'}, {'b', '1', '2'}, {'b', '1', '3'}, {'b', '1', '4'},
    {'b', '2', '1'}, {'b', '2', '2'}, {'b', '2', '3'}, {'b', '2', '4'},
    {'b', '3', '1'}, {'b', '3', '2'}, {'b', '3', '3'}, {'b', '3', '4'},
    {'\0', '\0', '\0'}
};

static int
OpenUserDefinedDevice(char *path, int maxlen, int flags)
{
    const char *audiodev;
    int audio_fd;

    /* Figure out what our audio device is */
    if ((audiodev = SDL_getenv("SDL_PATH_DSP")) == NULL) {
        audiodev = SDL_getenv("AUDIODEV");
    }
    if (audiodev == NULL) {
        return -1;
    }
    audio_fd = open(audiodev, flags, 0);
    if (path != NULL) {
        SDL_strlcpy(path, audiodev, maxlen);
        path[maxlen - 1] = '\0';
    }
    return audio_fd;
}

int
SDL_OpenAudioPath(char *path, int maxlen, int flags, int classic)
{
    struct stat sb;
    int audio_fd;
    char audiopath[1024];
    int cycle;

    audio_fd = OpenUserDefinedDevice(path, maxlen, flags);
    if (audio_fd != -1) {
        return audio_fd;
    }

    cycle = 0;
    while (devsettings[cycle][0] != '\0') {
        SDL_snprintf(audiopath, SDL_arraysize(audiopath),
                     _PATH_DEV_DSP,
                     devsettings[cycle][0],
                     devsettings[cycle][1], devsettings[cycle][2]);

        if (stat(audiopath, &sb) == 0) {
            audio_fd = open(audiopath, flags, 0);
            if (audio_fd > 0) {
                if (path != NULL) {
                    SDL_strlcpy(path, audiopath, maxlen);
                }
                return audio_fd;
            }
        }
    }
    return -1;
}

#endif /* Audio driver selection */
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