SDL_audiodev.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2016 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, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "../SDL_internal.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 <unistd.h> /* For close() */
#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
static void
test_device(const int iscapture, const char *fname, int flags, int (*test) (int fd))
{
struct stat sb;
if ((stat(fname, &sb) == 0) && (S_ISCHR(sb.st_mode))) {
const int audio_fd = open(fname, flags, 0);
if (audio_fd >= 0) {
const int okay = test(audio_fd);
close(audio_fd);
if (okay) {
static size_t dummyhandle = 0;
dummyhandle++;
SDL_assert(dummyhandle != 0);
SDL_AddAudioDevice(iscapture, fname, (void *) dummyhandle);
}
}
}
}
static int
test_stub(int fd)
{
return 1;
}
static void
SDL_EnumUnixAudioDevices_Internal(const int iscapture, const int classic, int (*test)(int))
{
const int flags = iscapture ? OPEN_FLAGS_INPUT : OPEN_FLAGS_OUTPUT;
const char *audiodev;
char audiopath[1024];
if (test == NULL)
test = test_stub;
/* 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;
}
}
}
test_device(iscapture, audiodev, flags, test);
if (SDL_strlen(audiodev) < (sizeof(audiopath) - 3)) {
int instance = 0;
while (instance++ <= 64) {
SDL_snprintf(audiopath, SDL_arraysize(audiopath),
"%s%d", audiodev, instance);
test_device(iscapture, audiopath, flags, test);
}
}
}
void
SDL_EnumUnixAudioDevices(const int classic, int (*test)(int))
{
SDL_EnumUnixAudioDevices_Internal(SDL_TRUE, classic, test);
SDL_EnumUnixAudioDevices_Internal(SDL_FALSE, classic, test);
}
#endif /* Audio driver selection */
/* vi: set ts=4 sw=4 expandtab: */
OPEN_FLAGS_INPUT
#define OPEN_FLAGS_INPUT
Definition: SDL_audiodev_c.h:33
SDL_audiodev_c.h
SDL_EnumUnixAudioDevices
void SDL_EnumUnixAudioDevices(const int classic, int(*test)(int))
OPEN_FLAGS_OUTPUT
#define OPEN_FLAGS_OUTPUT
Definition: SDL_audiodev_c.h:32
SDL_TRUE
Definition: SDL_stdinc.h:129
SDL_getenv
#define SDL_getenv
Definition: SDL_dynapi_overrides.h:384
SDL_assert
#define SDL_assert(condition)
Definition: SDL_assert.h:167
NULL
#define NULL
Definition: begin_code.h:143
SDL_stdinc.h
SDL_strlen
#define SDL_strlen
Definition: SDL_dynapi_overrides.h:399
SDL_FALSE
Definition: SDL_stdinc.h:128
SDL_snprintf
#define SDL_snprintf
Definition: SDL_dynapi_overrides.h:46
SDL_arraysize
#define SDL_arraysize(array)
Definition: SDL_stdinc.h:93
flags
GLbitfield flags
Definition: SDL_opengl_glext.h:1480
SDL_AddAudioDevice
void SDL_AddAudioDevice(const int iscapture, const char *name, void *handle)
Definition: SDL_audio.c:347