Added native OpenBSD audio driver (thanks vedge!)
authorSam Lantinga <slouken@lokigames.com>
Sat, 26 May 2001 16:58:37 +0000
changeset 37 3ad7157c6cfa
parent 36 13ee9f4834ea
child 38 80139f9b90d8
Added native OpenBSD audio driver (thanks vedge!)
README.OpenBSD
configure.in
docs.html
src/audio/Makefile.am
src/audio/SDL_audio.c
src/audio/SDL_sysaudio.h
src/audio/openbsd/Makefile.am
src/audio/openbsd/SDL_openbsdaudio.c
src/audio/openbsd/SDL_openbsdaudio.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/README.OpenBSD	Sat May 26 16:58:37 2001 +0000
@@ -0,0 +1,81 @@
+=============================================================
+Using the Simple DirectMedia Layer with OpenBSD 2.9 and later
+=============================================================
+
+Author: 
+Peter Valchev <pvalchev@openbsd.org>
+  
+=======
+Install 
+=======
+There is an OpenBSD port for SDL and various other tools.  Using
+this port is recommended, since it contains all the needed patches
+and configure arguments nicely organized in several FLAVORS you
+can pick from.  If you're unfamiliar with the OpenBSD ports system
+please visit:
+http://www.openbsd.org/ports.html
+http://www.openbsd.org/anoncvs.html
+
+You should have a precompiled binary package on your OpenBSD 2.9
+or later CD-ROM, which you can easily add with pkg_add(1).
+
+If for whatever reason you're unable to take the advantage of the
+created port, or you want to stick with the newest fresh SDL from
+the current CVS repository, here are some hints of what has left
+unresolved and needs to be disabled/changed.
+
+To build SDL with OSS + esound:
+
+1. ./configure --disable-joystick \
+	--disable-pthread-sem \
+	--disable-nasm \
+	--enable-esd \
+	--enable-oss \
+	--disable-arts \
+	--disable-video-opengl
+
+OR
+
+To build SDL with native audio + esound (remove --disable-esd otherwise):
+1. ./configure --disable-joystick \
+	--disable-pthread-sem \
+	--disable-nasm \
+	--enable-openbsdaudio \
+	--enable-esd \
+	--disable-arts \
+	--disable-video-opengl
+
+If you need arts or GL, omit the responding --disable lines.  In the
+port, they're disabled by default, you need to specify flavors to
+make use of them.
+
+2. gmake    # Yeah, GNU make is required, install the package 
+3. sudo gmake install
+
+=========
+Todo List 
+=========
+
+Feedback is always welcome with anything you may find useful and
+you can suggest.
+For now, the following things have to be worked on:
+
+1. The native audio should be widely tested and will eventually
+become the default.  At that moment I have not received any 
+feedback which should explain its current condition.
+
+2. There are occurences of dynamic loading of drivers in the OpenGL
+code section, and our a.out architectures need an underscore prefixed
+to symbol names.  Some solution to that may be a good thing.  I can
+fix it theoretically, but unfortunately I do not have the needed 
+hardware/configuration to test it.  If you bump into that, email me.
+
+===================
+Contact Information
+===================
+Everybody is welcome to give me any suggestions and to report bugs
+(as well as fixing them ;-)  You can contact me by email:
+Peter Valchev <pvalchev@openbsd.org>
+
+$Id$
+
--- a/configure.in	Wed May 23 23:35:10 2001 +0000
+++ b/configure.in	Sat May 26 16:58:37 2001 +0000
@@ -278,6 +278,19 @@
     fi
 }
 
+dnl Check whether we want to use OpenBSD native audio or not
+CheckOPENBSDAUDIO()
+{
+    AC_ARG_ENABLE(openbsdaudio,
+[  --enable-openbsdaudio   OpenBSD native audio support [default=no]],
+                  , enable_openbsdaudio=no)
+    if test x$enable_audio = xyes -a x$enable_openbsdaudio = xyes; then
+        SYSTEM_LIBS="$SYSTEM_LIBS $ESD_LIBS"
+        AUDIO_SUBDIRS="$AUDIO_SUBDIRS openbsd"
+        AUDIO_DRIVERS="$AUDIO_DRIVERS openbsd/libaudio_openbsd.la"
+    fi
+}
+
 dnl Find the ESD includes and libraries
 CheckESD()
 {
@@ -1275,7 +1288,6 @@
         ;;
     *-*-openbsd*)
         ARCH=openbsd
-        CFLAGS="$CFLAGS -Dunix"
         CheckDummyVideo
         CheckNASM
         CheckOSS
@@ -1289,10 +1301,7 @@
         # Set up files for the main() stub
         COPY_ARCH_SRC(src/main, linux, SDL_main.c)
         # Set up files for the audio library
-        if test x$enable_audio = xyes; then
-            AUDIO_SUBDIRS="$AUDIO_SUBDIRS sun"
-            AUDIO_DRIVERS="$AUDIO_DRIVERS sun/libaudio_sun.la"
-        fi
+        CheckOPENBSDAUDIO
         # Set up files for the joystick library
         # (No joystick support yet)
         if test x$enable_joystick = xyes; then
@@ -1322,6 +1331,8 @@
         if test x$enable_timers = xyes; then
             COPY_ARCH_SRC(src/timer, linux, SDL_systimer.c)
         fi
+        # OpenBSD does not define "unix"
+        CFLAGS="$CFLAGS -Dunix"
         ;;
     *-*-sysv5*)
         ARCH=sysv5
@@ -1882,7 +1893,7 @@
 fi
 
 if test $ARCH = openbsd; then
-  SDL_RLD_FLAGS="-Wl,-R\${exec_prefix}/lib -Wl,-R\${X11BASE}/lib"
+  SDL_RLD_FLAGS="-L${X11BASE}/lib -Wl,-rpath,\${exec_prefix}/lib -Wl,-rpath,${X11BASE}/lib"
 fi
 
 dnl Output the video drivers we use
@@ -1947,6 +1958,7 @@
 src/audio/macrom/Makefile
 src/audio/nas/Makefile
 src/audio/nto/Makefile
+src/audio/openbsd/Makefile
 src/audio/paudio/Makefile
 src/audio/sun/Makefile
 src/audio/ums/Makefile
--- a/docs.html	Wed May 23 23:35:10 2001 +0000
+++ b/docs.html	Sat May 26 16:58:37 2001 +0000
@@ -16,6 +16,7 @@
 Major changes since SDL 1.0.0:
 </H2>
 <UL>
+	<LI> 1.2.1: Added native OpenBSD audio driver (thanks vedge!)
 	<LI> 1.2.1: Added detection of Open Sound System on Solaris x86
 	<LI> 1.2.1: Added initial support for Nano-X (thanks Hsieh-Fu!)
 	<LI> 1.2.1: Fixed endian detection on IA64 architectures (thanks Bill!)
--- a/src/audio/Makefile.am	Wed May 23 23:35:10 2001 +0000
+++ b/src/audio/Makefile.am	Sat May 26 16:58:37 2001 +0000
@@ -6,7 +6,7 @@
 # Define which subdirectories need to be built
 SUBDIRS = @AUDIO_SUBDIRS@
 DIST_SUBDIRS = alsa arts baudio dma dmedia dsp esd macrom nas nto \
-               paudio sun ums windib windx5
+               openbsd paudio sun ums windib windx5
 
 DRIVERS = @AUDIO_DRIVERS@
 
--- a/src/audio/SDL_audio.c	Wed May 23 23:35:10 2001 +0000
+++ b/src/audio/SDL_audio.c	Sat May 26 16:58:37 2001 +0000
@@ -47,6 +47,9 @@
 #ifdef ALSA_SUPPORT
 	&ALSA_bootstrap,
 #endif
+#ifdef __OpenBSD__
+	&OBSD_bootstrap;
+#endif
 #if (defined(unix) && !defined(__CYGWIN32__)) && \
     !defined(OSS_SUPPORT) && !defined(ALSA_SUPPORT)
 	&AUDIO_bootstrap,
--- a/src/audio/SDL_sysaudio.h	Wed May 23 23:35:10 2001 +0000
+++ b/src/audio/SDL_sysaudio.h	Sat May 26 16:58:37 2001 +0000
@@ -106,6 +106,9 @@
 #ifdef ALSA_SUPPORT
 extern AudioBootStrap ALSA_bootstrap;
 #endif
+#ifdef __OpenBSD__
+extern AudioBootStrap OBSD_bootstrap;
+#endif
 #if (defined(unix) && !defined(__CYGWIN32__)) && \
     !defined(OSS_SUPPORT) && !defined(ALSA_SUPPORT)
 extern AudioBootStrap AUDIO_bootstrap;
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/audio/openbsd/Makefile.am	Sat May 26 16:58:37 2001 +0000
@@ -0,0 +1,9 @@
+
+## Makefile.am for SDL using the native OpenBSD sound driver
+
+noinst_LTLIBRARIES = libaudio_openbsd.la
+libaudio_openbsd_la_SOURCES = $(SRCS)
+
+# The SDL audio driver sources
+SRCS =	SDL_openbsdaudio.c	\
+	SDL_openbsdaudio.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/audio/openbsd/SDL_openbsdaudio.c	Sat May 26 16:58:37 2001 +0000
@@ -0,0 +1,408 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 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
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public
+    License along with this library; if not, write to the Free
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    Sam Lantinga
+    slouken@devolution.com
+*/
+
+/*
+ * Driver for native OpenBSD audio(4).
+ * vedge@vedge.com.ar.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <sys/time.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/audioio.h>
+
+#include "SDL_audio.h"
+#include "SDL_error.h"
+#include "SDL_audiomem.h"
+#include "SDL_audio_c.h"
+#include "SDL_timer.h"
+#include "SDL_audiodev_c.h"
+#include "SDL_openbsdaudio.h"
+
+/* The tag name used by OpenBSD audio */
+#define OBSD_DRIVER_NAME         "openbsd"
+
+/* Open the audio device for playback, and don't block if busy */
+/* #define USE_BLOCKING_WRITES */
+
+/* Use timer for synchronization */
+/* #define USE_TIMER_SYNC */
+
+/* #define DEBUG_AUDIO */
+/* #define DEBUG_AUDIO_STREAM */
+
+#ifdef USE_BLOCKING_WRITES
+#define OPEN_FLAGS	O_WRONLY
+#else
+#define OPEN_FLAGS	(O_WRONLY|O_NONBLOCK)
+#endif
+
+/* Audio driver functions */
+static void OBSD_WaitAudio(_THIS);
+static int OBSD_OpenAudio(_THIS, SDL_AudioSpec *spec);
+static void OBSD_PlayAudio(_THIS);
+static Uint8 *OBSD_GetAudioBuf(_THIS);
+static void OBSD_CloseAudio(_THIS);
+
+#ifdef DEBUG_AUDIO
+static void OBSD_Status(_THIS);
+#endif
+
+/* Audio driver bootstrap functions */
+
+static int
+Audio_Available(void)
+{
+    int fd;
+    int available;
+
+    available = 0;
+    fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 0);
+    if(fd >= 0) {
+	available = 1;
+	close(fd);
+    }
+    return(available);
+}
+
+static void
+Audio_DeleteDevice(SDL_AudioDevice *device)
+{
+    free(device->hidden);
+    free(device);
+}
+
+static SDL_AudioDevice
+*Audio_CreateDevice(int devindex)
+{
+    SDL_AudioDevice *this;
+
+    /* Initialize all variables that we clean on shutdown */
+    this = (SDL_AudioDevice*)malloc(sizeof(SDL_AudioDevice));
+    if(this) {
+	memset(this, 0, (sizeof *this));
+	this->hidden =
+	    (struct SDL_PrivateAudioData*)malloc((sizeof *this->hidden));
+    }
+    if((this == NULL) || (this->hidden == NULL)) {
+	SDL_OutOfMemory();
+	if(this) free(this);
+	return(0);
+    }
+    memset(this->hidden, 0, (sizeof *this->hidden));
+    audio_fd = -1;
+
+    /* Set the function pointers */
+    this->OpenAudio = OBSD_OpenAudio;
+    this->WaitAudio = OBSD_WaitAudio;
+    this->PlayAudio = OBSD_PlayAudio;
+    this->GetAudioBuf = OBSD_GetAudioBuf;
+    this->CloseAudio = OBSD_CloseAudio;
+
+    this->free = Audio_DeleteDevice;
+    
+    return this;
+}
+
+AudioBootStrap OBSD_bootstrap = {
+	OBSD_DRIVER_NAME, "Native OpenBSD audio",
+	Audio_Available, Audio_CreateDevice
+};
+
+/* This function waits until it is possible to write a full sound buffer */
+static void
+OBSD_WaitAudio(_THIS)
+{
+#ifndef USE_BLOCKING_WRITES
+    fd_set fdset;
+
+    /* Check to see if the thread-parent process is still alive */
+    {
+	static int cnt = 0;
+	/* Note that this only works with thread implementations 
+	   that use a different process id for each thread. */
+	if(parent && (((++cnt)%10) == 0)) { /* Check every 10 loops */
+	    if(kill(parent, 0) < 0)
+		this->enabled = 0;
+	}
+    }
+
+#ifdef USE_TIMER_SYNC
+    /* See if we need to use timed audio synchronization */
+    if(frame_ticks)
+    {
+	/* Use timer for general audio synchronization */
+	Sint32 ticks;
+
+	ticks = ((Sint32)(next_frame - SDL_GetTicks())) - FUDGE_TICKS;
+	if(ticks > 0)
+	    SDL_Delay(ticks);
+    }
+    else
+#endif /* USE_TIMER_SYNC */
+    {
+	/* Use select() for audio synchronization */
+	struct timeval timeout;
+	FD_ZERO(&fdset);
+	FD_SET(audio_fd, &fdset);
+	timeout.tv_sec = 10;
+	timeout.tv_usec = 0;
+	
+#if defined(DEBUG_AUDIO_STREAM) && defined(DEBUG_AUDIO_STREAM)
+	OBSD_Status(this);
+#endif
+	if(select(audio_fd+1, NULL, &fdset, NULL, &timeout) <= 0)
+	{
+	    const char *message =
+		"Audio timeout - buggy audio driver? (disabled)";
+	    fprintf(stderr, "SDL: %s\n", message);
+	    this->enabled = 0;
+	    audio_fd = -1;
+	}
+    }
+#endif /* !USE_BLOCKING_WRITES */
+
+}
+
+static void
+OBSD_PlayAudio(_THIS)
+{
+    int written;
+
+    /* Write the audio data, checking for EAGAIN on broken audio drivers */
+    do
+    {
+	written = write(audio_fd, mixbuf, mixlen);
+	if((written < 0) && ((errno == 0) || (errno == EAGAIN)))
+	    SDL_Delay(1);
+    }
+    while((written < 0) &&
+	((errno == 0) || (errno == EAGAIN) || (errno == EINTR)));
+
+#ifdef USE_TIMER_SYNC
+    if(frame_ticks)
+	next_frame += frame_ticks;
+#endif
+
+    /* If we couldn't write, assume fatal error for now */
+    if(written < 0)
+	this->enabled = 0;
+
+#ifdef DEBUG_AUDIO_STREAM
+    fprintf(stderr, "Wrote %d bytes of audio data\n", written);
+#endif
+}
+
+static Uint8
+*OBSD_GetAudioBuf(_THIS)
+{
+    return(mixbuf);
+}
+
+static void
+OBSD_CloseAudio(_THIS)
+{
+    if(mixbuf != NULL) {
+	SDL_FreeAudioMem(mixbuf);
+	mixbuf = NULL;
+    }
+    if(audio_fd >= 0) {
+	close(audio_fd);
+	audio_fd = -1;
+    }
+}
+
+#ifdef DEBUG_AUDIO
+void
+OBSD_Status(_THIS)
+{
+    audio_info_t info;
+
+    if(ioctl(audio_fd, AUDIO_GETINFO, &info) < 0) {
+	fprintf(stderr,"AUDIO_GETINFO failed.\n");
+	return;
+    }
+
+    fprintf(stderr,"
+[play/record info]
+buffer size	:   %d bytes
+sample rate	:   %i Hz
+channels	:   %i
+precision	:   %i-bit
+encoding	:   0x%x
+seek		:   %i
+sample count	:   %i
+EOF count	:   %i
+paused		:   %s
+error occured	:   %s
+waiting		:   %s
+active		:   %s
+",
+    info.play.buffer_size,
+    info.play.sample_rate,
+    info.play.channels,
+    info.play.precision,
+    info.play.encoding,
+    info.play.seek,
+    info.play.samples,
+    info.play.eof,
+    info.play.pause ? "yes" : "no",
+    info.play.error ? "yes" : "no",
+    info.play.waiting ? "yes" : "no",
+    info.play.active ? "yes": "no");
+
+    fprintf(stderr,"
+[audio info]
+monitor_gain	:   %i
+hw block size	:   %d bytes
+hi watermark	:   %i
+lo watermark	:   %i
+audio mode	:   %s
+",  
+    info.monitor_gain,
+    info.blocksize,
+    info.hiwat, info.lowat,
+    (info.mode == AUMODE_PLAY) ? "PLAY"
+    : (info.mode = AUMODE_RECORD) ? "RECORD"
+    : (info.mode == AUMODE_PLAY_ALL ? "PLAY_ALL"
+    : "???"));
+}
+#endif /* DEBUG_AUDIO */
+
+static int
+OBSD_OpenAudio(_THIS, SDL_AudioSpec *spec)
+{
+    char audiodev[64];
+    Uint16 setenc;
+    audio_encoding_t enc;
+    audio_info_t info;
+
+    AUDIO_INITINFO(&info);
+    
+    /* Calculate the final parameters for this audio specification */
+    SDL_CalculateAudioSpec(spec);
+
+#ifdef USE_TIMER_SYNC
+    frame_ticks = 0.0;
+#endif
+
+    /* Open the audio device */
+    audio_fd = SDL_OpenAudioPath(audiodev, sizeof(audiodev), OPEN_FLAGS, 0);
+    if(audio_fd < 0) {
+	SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno));
+	return(-1);
+    }
+    
+    /* Set to play mode */
+    info.mode = AUMODE_PLAY;
+    if(ioctl(audio_fd, AUDIO_SETINFO, &info) < 0) {
+	SDL_SetError("Couldn't put device into play mode");
+	return(-1);
+    }
+    
+    mixbuf = NULL;
+    setenc = 0;
+
+    for(enc.index = 0; (ioctl(audio_fd, AUDIO_GETENC, &enc)>=0)
+	&& (enc.encoding != setenc); enc.index++)
+    {
+	switch(spec->format)
+	{
+	    case AUDIO_U8:	/* 8-bit unsigned linear */
+		setenc = AUDIO_ENCODING_PCM8;
+		break;
+	    case AUDIO_S8:	/* 8-bit signed linear */
+		setenc = AUDIO_ENCODING_SLINEAR;
+		break;
+	    case AUDIO_U16LSB:  /* 16-bit unsigned linear, LSB */
+		setenc = AUDIO_ENCODING_ULINEAR_LE;
+		break;
+	    case AUDIO_U16MSB:  /* 16-bit unsigned linear, MSB */
+		setenc = AUDIO_ENCODING_ULINEAR_BE;
+		break;
+	    case AUDIO_S16LSB:  /* 16-bit signed linear, LSB */
+		setenc = AUDIO_ENCODING_SLINEAR_LE;
+		break;
+	    case AUDIO_S16MSB:  /* 16-bit signed linear, MSB */
+		setenc = AUDIO_ENCODING_SLINEAR_BE;
+		break;
+	}
+#ifdef DEBUG_AUDIO
+	fprintf(stderr,"encoding #%i: \"%s\" %i-bit (0x%x) flags=%i...\n",
+	    enc.index, enc.name, enc.precision, enc.encoding, enc.flags);
+#endif
+    }
+
+    if(!setenc) {
+	SDL_SetError("No supported encoding for 0x%x", spec->format);
+	return(-1);
+    }
+
+    /* Set audio encoding */
+    info.play.encoding = enc.encoding;
+    info.play.precision = enc.precision;
+    if((ioctl(audio_fd, AUDIO_SETINFO, &info) < 0)) {
+	SDL_SetError("Couldn't set encoding to 0x%x %i-bit",
+	    enc.encoding, enc.precision);
+	return(-1);
+    }
+
+    /* Set audio channels */
+    info.play.channels = spec->channels;
+    if(ioctl(audio_fd, AUDIO_SETINFO, &info) < 0) {
+	info.play.channels = (spec->channels > 1);
+	ioctl(audio_fd, AUDIO_SETINFO, &info);
+    }
+
+    /* Set the sample rate */
+    info.play.sample_rate = spec->freq;
+    if(ioctl(audio_fd, AUDIO_SETINFO, &info) < 0) {
+	SDL_SetError("Couldn't set sample rate to %i Hz", spec->freq);
+	return(-1);
+    }
+
+    /* Allocate mixing buffer */
+    mixlen = spec->size;
+    mixbuf = (Uint8*)SDL_AllocAudioMem(mixlen);
+    if(mixbuf == NULL) {
+	return(-1);
+    }
+    memset(mixbuf, spec->silence, spec->size);
+    
+    /* Get the parent process id (we're the parent of the audio thread) */
+    parent = getpid();
+
+#ifdef DEBUG_AUDIO
+    OBSD_Status(this);
+#endif
+
+    /* We're ready to rock and roll. :-) */
+    return(0);
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/audio/openbsd/SDL_openbsdaudio.h	Sat May 26 16:58:37 2001 +0000
@@ -0,0 +1,57 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Library General Public
+    License as published by the Free Software Foundation; either
+    version 2 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
+    Library General Public License for more details.
+
+    You should have received a copy of the GNU Library General Public
+    License along with this library; if not, write to the Free
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    Sam Lantinga
+    slouken@devolution.com
+*/
+
+#ifndef _SDL_openbsdaudio_h
+#define _SDL_openbsdaudio_h
+
+#include "SDL_sysaudio.h"
+
+#define _THIS	SDL_AudioDevice *this
+
+struct SDL_PrivateAudioData
+{
+    /* The file descriptor for the audio device */
+    int audio_fd;
+
+    /* The parent process id, to detect when application quits */
+    pid_t parent;
+
+    /* Raw mixing buffer */
+    Uint8 *mixbuf;
+    int    mixlen;
+
+    /* Support for audio timing using a timer, in addition to select() */
+    float frame_ticks;
+    float next_frame;
+};
+
+#define FUDGE_TICKS	10	/* The scheduler overhead ticks per frame */
+
+/* Old variable names */
+#define audio_fd		(this->hidden->audio_fd)
+#define parent			(this->hidden->parent)
+#define mixbuf			(this->hidden->mixbuf)
+#define mixlen			(this->hidden->mixlen)
+#define frame_ticks		(this->hidden->frame_ticks)
+#define next_frame		(this->hidden->next_frame)
+
+#endif /* _SDL_openbsdaudio_h */