From 0070d29e34948a9a4efb71fa0160f20597694ec9 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@lokigames.com>
Date: Sat, 16 Jun 2001 01:51:42 +0000
Subject: [PATCH] Added an audio driver that writes to disk (thanks Ryan!)

---
 configure.in                   |  32 +++++
 docs.html                      |   1 +
 src/audio/Makefile.am          |   3 +-
 src/audio/SDL_audio.c          |   4 +-
 src/audio/SDL_sysaudio.h       |   3 +
 src/audio/disk/.cvsignore      |   6 +
 src/audio/disk/Makefile.am     |   9 ++
 src/audio/disk/SDL_diskaudio.c | 222 +++++++++++++++++++++++++++++++++
 src/audio/disk/SDL_diskaudio.h |  44 +++++++
 9 files changed, 321 insertions(+), 3 deletions(-)
 create mode 100644 src/audio/disk/.cvsignore
 create mode 100644 src/audio/disk/Makefile.am
 create mode 100644 src/audio/disk/SDL_diskaudio.c
 create mode 100644 src/audio/disk/SDL_diskaudio.h

diff --git a/configure.in b/configure.in
index f03942cbb..55c130ee7 100644
--- a/configure.in
+++ b/configure.in
@@ -368,6 +368,21 @@ CheckNAS()
     fi
 }
 
+
+dnl rcg07142001 See if the user wants the disk writer audio driver...
+CheckDiskAudio()
+{
+    AC_ARG_ENABLE(diskaudio,
+[  --enable-diskaudio  	  support the disk writer audio driver [default=no]],
+                  , enable_diskaudio=no)
+    if test x$enable_audio = xyes -a x$enable_diskaudio = xyes; then
+        CFLAGS="$CFLAGS -DDISKAUD_SUPPORT"
+        AUDIO_SUBDIRS="$AUDIO_SUBDIRS disk"
+        AUDIO_DRIVERS="$AUDIO_DRIVERS disk/libaudio_disk.la"
+    fi
+}
+
+
 dnl See if we can use x86 assembly blitters
 CheckNASM()
 {
@@ -1085,6 +1100,7 @@ case "$target" in
     *-*-linux*)
         ARCH=linux
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckOSS
         CheckALSA
@@ -1151,6 +1167,7 @@ case "$target" in
     *-*-bsdi*)
         ARCH=bsdi
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1194,6 +1211,7 @@ case "$target" in
     *-*-freebsd*)
         ARCH=freebsd
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1246,6 +1264,7 @@ case "$target" in
     *-*-netbsd*)
         ARCH=netbsd
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1297,6 +1316,7 @@ case "$target" in
     *-*-openbsd*)
         ARCH=openbsd
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1345,6 +1365,7 @@ case "$target" in
     *-*-sysv5*)
         ARCH=sysv5
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1392,6 +1413,7 @@ case "$target" in
         ARCH=solaris
         CFLAGS="$CFLAGS -D__ELF__" # Fix for nasm on Solaris x86
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckOSS
         CheckARTSC
@@ -1438,6 +1460,7 @@ case "$target" in
     *-*-irix*)
         ARCH=irix
         CheckDummyVideo
+        CheckDiskAudio
         CheckNAS
         CheckX11
         CheckAAlib
@@ -1496,6 +1519,7 @@ case "$target" in
     *-*-hpux*)
         ARCH=hpux
         CheckDummyVideo
+        CheckDiskAudio
         CheckOSS
         CheckNAS
         CheckX11
@@ -1540,6 +1564,7 @@ case "$target" in
     *-*-aix*)
         ARCH=aix
         CheckDummyVideo
+        CheckDiskAudio
         CheckOSS
         CheckNAS
         CheckX11
@@ -1583,6 +1608,7 @@ case "$target" in
     *-*-osf*)
         ARCH=osf
         CheckDummyVideo
+        CheckDiskAudio
         CheckNAS
         CheckX11
         CheckGGI
@@ -1626,6 +1652,7 @@ case "$target" in
     *-*-qnx*)
         ARCH=qnx
         CheckDummyVideo
+        CheckDiskAudio
         CheckNAS
         CheckPHOTON
         CheckX11
@@ -1680,6 +1707,7 @@ case "$target" in
             fi
         fi
         CheckDummyVideo
+        CheckDiskAudio
         CheckWIN32
         CheckDIRECTX
         CheckNASM
@@ -1736,6 +1764,7 @@ case "$target" in
         ARCH=beos
         ac_default_prefix=/boot/develop/tools/gnupro
         CheckDummyVideo
+        CheckDiskAudio
         CheckNASM
         CheckBWINDOW
         CheckBeGL
@@ -1781,6 +1810,7 @@ case "$target" in
         # for which this case would be handy.
         ARCH=macos
         CheckDummyVideo
+        CheckDiskAudio
         CheckTOOLBOX
         CheckMacGL
         # Set up files for the main() stub
@@ -1824,6 +1854,7 @@ case "$target" in
         # config.guess comes back with "darwin", so go with the flow.
         ARCH=macos
         CheckDummyVideo
+        CheckDiskAudio
         CheckCARBON
         CheckMacGL
         CheckPTHREAD
@@ -1973,6 +2004,7 @@ src/audio/sun/Makefile
 src/audio/ums/Makefile
 src/audio/windib/Makefile
 src/audio/windx5/Makefile
+src/audio/disk/Makefile
 src/video/Makefile
 src/video/cybergfx/Makefile
 src/video/x11/Makefile
diff --git a/docs.html b/docs.html
index f27b858fe..d6210b254 100644
--- a/docs.html
+++ b/docs.html
@@ -16,6 +16,7 @@ <H2>
 Major changes since SDL 1.0.0:
 </H2>
 <UL>
+	<LI> 1.2.1: Added an audio driver that writes to disk (thanks Ryan!)
 	<LI> 1.2.1: Mouse wheel sends mouse button (4/5) events on Windows
 	<LI> 1.2.1: Added MacOS X Project Builder projects (thanks Darrell!)
 	<LI> 1.2.1: Added initial support for Quartz video (thanks Darrell!)
diff --git a/src/audio/Makefile.am b/src/audio/Makefile.am
index b182d98dc..df23540b1 100644
--- a/src/audio/Makefile.am
+++ b/src/audio/Makefile.am
@@ -5,8 +5,7 @@ noinst_LTLIBRARIES = libaudio.la
 
 # Define which subdirectories need to be built
 SUBDIRS = @AUDIO_SUBDIRS@
-DIST_SUBDIRS = alsa arts baudio dma dmedia dsp esd macrom nas nto \
-               openbsd paudio sun ums windib windx5
+DIST_SUBDIRS = alsa arts baudio dma dmedia dsp esd macrom nas nto openbsd paudio sun ums windib windx5 disk
 
 DRIVERS = @AUDIO_DRIVERS@
 
diff --git a/src/audio/SDL_audio.c b/src/audio/SDL_audio.c
index 6723097e7..dd2ad84db 100644
--- a/src/audio/SDL_audio.c
+++ b/src/audio/SDL_audio.c
@@ -81,7 +81,9 @@ static AudioBootStrap *bootstrap[] = {
 #ifdef ENABLE_AHI
 	&AHI_bootstrap,
 #endif
-
+#ifdef DISKAUD_SUPPORT
+	&DISKAUD_bootstrap,
+#endif
 	NULL
 };
 SDL_AudioDevice *current_audio = NULL;
diff --git a/src/audio/SDL_sysaudio.h b/src/audio/SDL_sysaudio.h
index 7f396daaf..0bfc1ad2f 100644
--- a/src/audio/SDL_sysaudio.h
+++ b/src/audio/SDL_sysaudio.h
@@ -140,6 +140,9 @@ extern AudioBootStrap SNDMGR_bootstrap;
 #ifdef ENABLE_AHI
 extern AudioBootStrap AHI_bootstrap;
 #endif
+#ifdef DISKAUD_SUPPORT
+extern AudioBootStrap DISKAUD_bootstrap;
+#endif
 
 /* This is the current audio device */
 extern SDL_AudioDevice *current_audio;
diff --git a/src/audio/disk/.cvsignore b/src/audio/disk/.cvsignore
new file mode 100644
index 000000000..899d53557
--- /dev/null
+++ b/src/audio/disk/.cvsignore
@@ -0,0 +1,6 @@
+Makefile.in
+Makefile
+.libs
+*.o
+*.lo
+*.la
diff --git a/src/audio/disk/Makefile.am b/src/audio/disk/Makefile.am
new file mode 100644
index 000000000..ab3310a8b
--- /dev/null
+++ b/src/audio/disk/Makefile.am
@@ -0,0 +1,9 @@
+
+## Makefile.am for SDL audio "driver" that writes to a file.
+
+noinst_LTLIBRARIES = libaudio_disk.la
+libaudio_disk_la_SOURCES = $(SRCS)
+
+# The SDL audio driver sources
+SRCS =	SDL_diskaudio.c	\
+	SDL_diskaudio.h
diff --git a/src/audio/disk/SDL_diskaudio.c b/src/audio/disk/SDL_diskaudio.c
new file mode 100644
index 000000000..4185982f8
--- /dev/null
+++ b/src/audio/disk/SDL_diskaudio.c
@@ -0,0 +1,222 @@
+/*
+    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
+
+    This file hacked^H^H^H^H^H^Hwritten by Ryan C. Gordon
+        (icculus@linuxgames.com)
+*/
+
+#ifdef SAVE_RCSID
+static char rcsid =
+ "@(#) $Id$";
+#endif
+
+/* Output raw audio data to a file. */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.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_diskaudio.h"
+
+/* The tag name used by DISK audio */
+#define DISKAUD_DRIVER_NAME         "disk"
+
+/* environment variables and defaults. */
+#define DISKENVR_OUTFILE         "SDL_DISKAUDIOFILE"
+#define DISKDEFAULT_OUTFILE      "sdlaudio.raw"
+#define DISKENVR_WRITEDELAY      "SDL_DISKAUDIODELAY"
+#define DISKDEFAULT_WRITEDELAY   150
+
+/* Audio driver functions */
+static int DISKAUD_OpenAudio(_THIS, SDL_AudioSpec *spec);
+static void DISKAUD_WaitAudio(_THIS);
+static void DISKAUD_PlayAudio(_THIS);
+static Uint8 *DISKAUD_GetAudioBuf(_THIS);
+static void DISKAUD_CloseAudio(_THIS);
+
+static const char *DISKAUD_GetOutputFilename(void)
+{
+    const char *envr = getenv(DISKENVR_OUTFILE);
+    return((envr != NULL) ? envr : DISKDEFAULT_OUTFILE);
+}
+
+/* Audio driver bootstrap functions */
+static int DISKAUD_Available(void)
+{
+#if 0
+    int fd;
+	int available;
+    int exists = 0;
+    struct stat statbuf;
+    const char *fname = DISKAUD_GetOutputFilename();
+
+	available = 0;
+
+    if (stat(fname, &statbuf) == 0)
+        exists = 1;
+
+    fd = open(fname, O_WRONLY | O_CREAT | O_APPEND, S_IRUSR | S_IWUSR);
+	if ( fd != -1 ) {
+		available = 1;
+		close(fd);
+        if (!exists) {
+            unlink(fname);
+        }
+	}
+	return(available);
+#else
+    return(1);
+#endif
+}
+
+static void DISKAUD_DeleteDevice(SDL_AudioDevice *device)
+{
+	free(device->hidden);
+	free(device);
+}
+
+static SDL_AudioDevice *DISKAUD_CreateDevice(int devindex)
+{
+	SDL_AudioDevice *this;
+    const char *envr;
+
+	/* 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));
+
+    envr = getenv(DISKENVR_WRITEDELAY);
+    this->hidden->write_delay = (envr) ? atoi(envr) : DISKDEFAULT_WRITEDELAY;
+
+	/* Set the function pointers */
+	this->OpenAudio = DISKAUD_OpenAudio;
+	this->WaitAudio = DISKAUD_WaitAudio;
+	this->PlayAudio = DISKAUD_PlayAudio;
+	this->GetAudioBuf = DISKAUD_GetAudioBuf;
+	this->CloseAudio = DISKAUD_CloseAudio;
+
+	this->free = DISKAUD_DeleteDevice;
+
+	return this;
+}
+
+AudioBootStrap DISKAUD_bootstrap = {
+	DISKAUD_DRIVER_NAME, "direct-to-disk audio",
+	DISKAUD_Available, DISKAUD_CreateDevice
+};
+
+/* This function waits until it is possible to write a full sound buffer */
+static void DISKAUD_WaitAudio(_THIS)
+{
+    SDL_Delay(this->hidden->write_delay);
+}
+
+static void DISKAUD_PlayAudio(_THIS)
+{
+	int written;
+
+	/* Write the audio data, checking for EAGAIN on broken audio drivers */
+	do {
+		written = write(this->hidden->audio_fd,
+                        this->hidden->mixbuf,
+                        this->hidden->mixlen);
+		if ( (written < 0) && ((errno == 0) || (errno == EAGAIN)) ) {
+			SDL_Delay(1);	/* Let a little CPU time go by */
+		}
+	} while ( (written < 0) && 
+	          ((errno == 0) || (errno == EAGAIN) || (errno == EINTR)) );
+
+	/* If we couldn't write, assume fatal error for now */
+	if ( written < 0 ) {
+		this->enabled = 0;
+	}
+#ifdef DEBUG_AUDIO
+	fprintf(stderr, "Wrote %d bytes of audio data\n", written);
+#endif
+}
+
+static Uint8 *DISKAUD_GetAudioBuf(_THIS)
+{
+	return(this->hidden->mixbuf);
+}
+
+static void DISKAUD_CloseAudio(_THIS)
+{
+	if ( this->hidden->mixbuf != NULL ) {
+		SDL_FreeAudioMem(this->hidden->mixbuf);
+		this->hidden->mixbuf = NULL;
+	}
+	if ( this->hidden->audio_fd >= 0 ) {
+		close(this->hidden->audio_fd);
+		this->hidden->audio_fd = -1;
+	}
+}
+
+static int DISKAUD_OpenAudio(_THIS, SDL_AudioSpec *spec)
+{
+    const char *fname = DISKAUD_GetOutputFilename();
+
+	/* Open the audio device */
+    this->hidden->audio_fd = open(fname, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
+	if ( this->hidden->audio_fd < 0 ) {
+		SDL_SetError("Couldn't open %s: %s", fname, strerror(errno));
+		return(-1);
+	}
+
+    fprintf(stderr, "WARNING: You are using the SDL disk writer"
+                    " audio driver!\n Writing to file [%s].\n", fname);
+
+	/* Allocate mixing buffer */
+	this->hidden->mixlen = spec->size;
+	this->hidden->mixbuf = (Uint8 *) SDL_AllocAudioMem(this->hidden->mixlen);
+	if ( this->hidden->mixbuf == NULL ) {
+		return(-1);
+	}
+	memset(this->hidden->mixbuf, spec->silence, spec->size);
+
+	/* We're ready to rock and roll. :-) */
+	return(0);
+}
+
diff --git a/src/audio/disk/SDL_diskaudio.h b/src/audio/disk/SDL_diskaudio.h
new file mode 100644
index 000000000..0046f0b76
--- /dev/null
+++ b/src/audio/disk/SDL_diskaudio.h
@@ -0,0 +1,44 @@
+/*
+    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
+*/
+
+#ifdef SAVE_RCSID
+static char rcsid =
+ "@(#) $Id$";
+#endif
+
+#ifndef _SDL_diskaudio_h
+#define _SDL_diskaudio_h
+
+#include "SDL_sysaudio.h"
+
+/* Hidden "this" pointer for the video functions */
+#define _THIS	SDL_AudioDevice *this
+
+struct SDL_PrivateAudioData {
+	/* The file descriptor for the audio device */
+	int audio_fd;
+    Uint8 *mixbuf;
+    Uint32 mixlen;
+    Uint32 write_delay;
+};
+
+#endif /* _SDL_diskaudio_h */