Added MacOS X CD-ROM audio support (thanks Max and Darrell)

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%40614

configure.in

@@ -2404,8 +2404,9 @@ case "$target" in
         fi
         # Set up files for the cdrom library
         if test x$enable_cdrom = xyes; then
-            CDROM_SUBDIRS="$CDROM_SUBDIRS dummy"
-            CDROM_DRIVERS="$CDROM_DRIVERS dummy/libcdrom_dummy.la"
+            CDROM_SUBDIRS="$CDROM_SUBDIRS macosx"
+            CDROM_DRIVERS="$CDROM_DRIVERS macosx/libcdrom_macosx.la"
+            SYSTEM_LIBS="$SYSTEM_LIBS -framework AudioToolbox -framework AudioUnit -lstdc++"
         fi
         # Set up files for the thread library
         if test x$enable_threads = xyes; then
@@ -2672,6 +2673,7 @@ src/cdrom/bsdi/Makefile
 src/cdrom/freebsd/Makefile
 src/cdrom/linux/Makefile
 src/cdrom/macos/Makefile
+src/cdrom/macosx/Makefile
 src/cdrom/openbsd/Makefile
 src/cdrom/qnx/Makefile
 src/cdrom/win32/Makefile

src/cdrom/Makefile.am

@@ -5,7 +5,19 @@ noinst_LTLIBRARIES = libcdrom.la
 
 # Define which subdirectories need to be built
 SUBDIRS = @CDROM_SUBDIRS@
-DIST_SUBDIRS = aix beos bsdi dc dummy freebsd linux macos openbsd qnx win32
+DIST_SUBDIRS = \
+	aix \
+	beos \
+	bsdi \
+	dc \
+	dummy \
+	freebsd \
+	linux \
+	macos \
+	macosx \
+	openbsd \
+	qnx \
+	win32
 
 DRIVERS = @CDROM_DRIVERS@
 

src/cdrom/macosx/AudioFilePlayer.h

+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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@libsdl.org
+
+    This file based on Apple sample code. We haven't changed the file name, 
+    so if you want to see the original search for it on apple.com/developer
+*/
+
+//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//  AudioFilePlayer.h
+//
+#ifndef __AudioFilePlayer_H__
+#define __AudioFilePlayer_H__
+
+#include <CoreServices/CoreServices.h>
+
+#include <AudioToolbox/AudioToolbox.h>
+#include <AudioUnit/AudioUnit.h>
+
+#include "SDL_Error.h"
+
+const char* AudioFilePlayerErrorStr (OSStatus error);
+
+void ThrowResult (OSStatus result, const char *str);
+
+#define THROW_RESULT(str)                                       \
+    if (result) {                                               \
+        ThrowResult (result, str);                              \
+    }
+
+typedef void (*AudioFilePlayNotifier)(void          *inRefCon,
+                                    OSStatus        inStatus);
+
+enum {
+    kAudioFilePlayErr_FilePlayUnderrun = -10000,
+    kAudioFilePlay_FileIsFinished = -10001,
+    kAudioFilePlay_PlayerIsUninitialized = -10002
+};
+
+
+class AudioFileManager;
+
+#pragma mark __________ AudioFilePlayer
+class AudioFilePlayer
+{
+public:
+    AudioFilePlayer (const FSRef    *inFileRef);
+    
+    ~AudioFilePlayer();
+
+    void            SetDestination (AudioUnit                   &inDestUnit, 
+                                int                             inBusNumber);
+    
+    void            SetNotifier (AudioFilePlayNotifier inNotifier, void *inRefCon)
+    {
+        mNotifier = inNotifier;
+        mRefCon = inRefCon;
+    }
+    
+    void            SetStartFrame (int frame); // seek in the file
+    
+    int             GetCurrentFrame (); // get the current frame position
+    
+    void            SetStopFrame (int frame);   // set limit in the file
+    
+    void            Connect();
+    
+    void            Disconnect();
+
+    void            DoNotification (OSStatus inError) const;
+    
+    bool            IsConnected () const { return mConnected; }
+
+    UInt32          GetBusNumber () const { return mBusNumber; }
+    
+    AudioUnit       GetDestUnit () const { return mPlayUnit; }
+    
+    AudioConverterRef   GetAudioConverter() const { return mConverter; }
+
+#if DEBUG    
+    void            Print() const 
+    {
+        CAShow (mAudioFileID);
+        printf ("Destination Bus:%ld\n", GetBusNumber());
+        printf ("Is 'aunt' unit:%s\n", (mIsAUNTUnit ? "true" : "false"));
+        printf ("Is Connected:%s\n", (IsConnected() ? "true" : "false"));
+        if (mConverter) CAShow (mConverter);
+          printf ("- - - - - - - - - - - - - - \n");
+    }
+#endif
+
+    const AudioStreamBasicDescription&      GetFileFormat() const { return mFileDescription; }
+    
+private:
+    AudioUnit                       mPlayUnit;
+    UInt32                          mBusNumber;
+    AudioFileID                     mAudioFileID;
+    
+    AudioUnitInputCallback          mInputCallback;
+
+    AudioStreamBasicDescription     mFileDescription;
+    
+    bool                            mConnected;
+    bool                            mIsAUNTUnit;
+    
+    AudioFileManager*               mAudioFileManager;
+    AudioConverterRef               mConverter;
+    
+    AudioFilePlayNotifier           mNotifier;
+    void*                           mRefCon;
+    
+    int                             mStartFrame;
+    
+#pragma mark __________ Private_Methods
+    
+    void        OpenFile (const FSRef *inRef, SInt64& outFileSize);
+};
+
+#pragma mark __________ AudioFileManager
+class AudioFileManager
+{
+public:
+    AudioFileManager (AudioFilePlayer& inParent, AudioFileID inFile)
+        : mParent (inParent),
+          mAudioFileID (inFile),
+          mFileBuffer (0),
+          mByteCounter (0)
+        {}
+    
+    virtual ~AudioFileManager();
+    
+    
+    void                Connect (AudioConverterRef inConverter) 
+    {
+        mParentConverter = inConverter;
+        DoConnect();
+    }
+
+        // this method should NOT be called by an object of this class
+        // as it is called by the parent's Disconnect() method
+    virtual void        Disconnect () {}
+
+    const AudioFileID&  GetFileID() const { return mAudioFileID; }
+
+    const char*         GetFileBuffer () { return mFileBuffer; }
+
+    const AudioFilePlayer&  GetParent () const { return mParent; }
+    
+    virtual void        SetPosition (SInt64 pos) = 0;  // seek/rewind in the file
+    
+    virtual int         GetByteCounter () { return mByteCounter; } // return actual bytes streamed to audio hardware
+    
+    virtual void        SetEndOfFile (SInt64 pos) = 0;  // set the "EOF" (will behave just like it reached eof)
+   
+protected:
+    AudioFilePlayer&            mParent;
+    AudioConverterRef           mParentConverter;
+    const AudioFileID           mAudioFileID;
+    
+    char*                       mFileBuffer;
+
+    OSStatus            Render (AudioBuffer &ioData);
+
+    int                         mByteCounter;
+    
+    virtual OSStatus    GetFileData (void** inOutData, UInt32 *inOutDataSize) = 0;
+    
+    virtual void        DoConnect () = 0;
+        
+    virtual void        AfterRender () = 0;
+
+public:
+    static OSStatus     FileInputProc (void                             *inRefCon, 
+                                        AudioUnitRenderActionFlags      inActionFlags,
+                                        const AudioTimeStamp            *inTimeStamp, 
+                                        UInt32                          inBusNumber, 
+                                        AudioBuffer                     *ioData);
+    static OSStatus     ACInputProc (AudioConverterRef          inAudioConverter,
+                                            UInt32*                     outDataSize,
+                                            void**                      outData,
+                                            void*                       inUserData);
+};
+
+
+#pragma mark __________ AudioFileReaderThread
+class AudioFileReaderThread 
+    : public AudioFileManager
+{
+public:
+    const UInt32    mChunkSize;
+    SInt64          mFileLength;
+    SInt64          mReadFilePosition;
+    bool            mWriteToFirstBuffer;
+    bool            mFinishedReadingData;
+    
+    AudioFileReaderThread (AudioFilePlayer  &inParent, 
+                            AudioFileID     &inFile, 
+                            SInt64          inFileLength,
+                            UInt32          inChunkSize);
+    
+    virtual void        Disconnect ();
+
+    virtual void        SetPosition (SInt64 pos);  // seek/rewind in the file
+    
+    virtual void        SetEndOfFile (SInt64 pos);  // set the "EOF" (will behave just like it reached eof)
+    
+protected:
+    virtual void        DoConnect ();
+
+    virtual OSStatus    GetFileData (void** inOutData, UInt32 *inOutDataSize);
+
+    virtual void        AfterRender ();
+
+private:
+    bool                        mReadFromFirstBuffer;
+    bool                        mLockUnsuccessful;
+    bool                        mIsEngaged;
+    
+    int                         mNumTimesAskedSinceFinished;
+};
+
+
+#endif

src/cdrom/macosx/CAGuard.cpp

+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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@libsdl.org
+*/
+/*  
+    Note: This file hasn't been modified so technically we have to keep the disclaimer :-(
+    
+    Copyright:  © Copyright 2002 Apple Computer, Inc. All rights reserved.
+
+    Disclaimer: IMPORTANT:  This Apple software is supplied to you by Apple Computer, Inc.
+            ("Apple") in consideration of your agreement to the following terms, and your
+            use, installation, modification or redistribution of this Apple software
+            constitutes acceptance of these terms.  If you do not agree with these terms,
+            please do not use, install, modify or redistribute this Apple software.
+
+            In consideration of your agreement to abide by the following terms, and subject
+            to these terms, Apple grants you a personal, non-exclusive license, under AppleÕs
+            copyrights in this original Apple software (the "Apple Software"), to use,
+            reproduce, modify and redistribute the Apple Software, with or without
+            modifications, in source and/or binary forms; provided that if you redistribute
+            the Apple Software in its entirety and without modifications, you must retain
+            this notice and the following text and disclaimers in all such redistributions of
+            the Apple Software.  Neither the name, trademarks, service marks or logos of
+            Apple Computer, Inc. may be used to endorse or promote products derived from the
+            Apple Software without specific prior written permission from Apple.  Except as
+            expressly stated in this notice, no other rights or licenses, express or implied,
+            are granted by Apple herein, including but not limited to any patent rights that
+            may be infringed by your derivative works or by other works in which the Apple
+            Software may be incorporated.
+
+            The Apple Software is provided by Apple on an "AS IS" basis.  APPLE MAKES NO
+            WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
+            WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+            PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN
+            COMBINATION WITH YOUR PRODUCTS.
+
+            IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
+            CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+            GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+            ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION
+            OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF CONTRACT, TORT
+            (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN
+            ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+/*=============================================================================
+    CAGuard.cp
+
+=============================================================================*/
+
+//=============================================================================
+//  Includes
+//=============================================================================
+
+#include <stdio.h>
+
+#define NDEBUG 1
+#include <assert.h>
+
+
+#include "CAGuard.h"
+
+//#warning      Need a try-based Locker too
+//=============================================================================
+//  CAGuard
+//=============================================================================
+
+CAGuard::CAGuard()
+{
+    OSStatus theError = pthread_mutex_init(&mMutex, NULL);
+    assert(theError == 0);
+    
+    theError = pthread_cond_init(&mCondVar, NULL);
+    assert(theError == 0);
+    
+    mOwner = 0;
+}
+
+CAGuard::~CAGuard()
+{
+    pthread_mutex_destroy(&mMutex);
+    pthread_cond_destroy(&mCondVar);
+}
+
+bool    CAGuard::Lock()
+{
+    bool theAnswer = false;
+    
+    if(pthread_self() != mOwner)
+    {
+        OSStatus theError = pthread_mutex_lock(&mMutex);
+        assert(theError == 0);
+        mOwner = pthread_self();
+        theAnswer = true;
+    }
+
+    return theAnswer;
+}
+
+void    CAGuard::Unlock()
+{
+    assert(pthread_self() == mOwner);
+
+    mOwner = 0;
+    OSStatus theError = pthread_mutex_unlock(&mMutex);
+    assert(theError == 0);
+}
+
+bool    CAGuard::Try (bool& outWasLocked)
+{
+    bool theAnswer = false;
+    outWasLocked = false;
+    
+    if (pthread_self() == mOwner) {
+        theAnswer = true;
+        outWasLocked = false;
+    } else {
+        OSStatus theError = pthread_mutex_trylock(&mMutex);
+        if (theError == 0) {
+            mOwner = pthread_self();
+            theAnswer = true;
+            outWasLocked = true;
+        }
+    }
+    
+    return theAnswer;
+}
+
+void    CAGuard::Wait()
+{
+    assert(pthread_self() == mOwner);
+
+    mOwner = 0;
+
+    OSStatus theError = pthread_cond_wait(&mCondVar, &mMutex);
+    assert(theError == 0);
+    mOwner = pthread_self();
+}
+
+void    CAGuard::Notify()
+{
+    OSStatus theError = pthread_cond_signal(&mCondVar);
+    assert(theError == 0);
+}

src/cdrom/macosx/CAGuard.h

+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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@libsdl.org
+*/
+/*  
+    Note: This file hasn't been modified so technically we have to keep the disclaimer :-(
+
+
+    Copyright:  © Copyright 2002 Apple Computer, Inc. All rights reserved.
+
+    Disclaimer: IMPORTANT:  This Apple software is supplied to you by Apple Computer, Inc.
+            ("Apple") in consideration of your agreement to the following terms, and your
+            use, installation, modification or redistribution of this Apple software
+            constitutes acceptance of these terms.  If you do not agree with these terms,
+            please do not use, install, modify or redistribute this Apple software.
+
+            In consideration of your agreement to abide by the following terms, and subject
+            to these terms, Apple grants you a personal, non-exclusive license, under AppleÕs
+            copyrights in this original Apple software (the "Apple Software"), to use,
+            reproduce, modify and redistribute the Apple Software, with or without
+            modifications, in source and/or binary forms; provided that if you redistribute
+            the Apple Software in its entirety and without modifications, you must retain
+            this notice and the following text and disclaimers in all such redistributions of
+            the Apple Software.  Neither the name, trademarks, service marks or logos of
+            Apple Computer, Inc. may be used to endorse or promote products derived from the
+            Apple Software without specific prior written permission from Apple.  Except as
+            expressly stated in this notice, no other rights or licenses, express or implied,
+            are granted by Apple herein, including but not limited to any patent rights that
+            may be infringed by your derivative works or by other works in which the Apple
+            Software may be incorporated.
+
+            The Apple Software is provided by Apple on an "AS IS" basis.  APPLE MAKES NO
+            WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
+            WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+            PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN
+            COMBINATION WITH YOUR PRODUCTS.
+
+            IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
+            CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+            GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+            ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR DISTRIBUTION
+            OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF CONTRACT, TORT
+            (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN
+            ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+/*=============================================================================
+    CAGuard.h
+
+=============================================================================*/
+#if !defined(__CAGuard_h__)
+#define __CAGuard_h__
+
+//=============================================================================
+//  Includes
+//=============================================================================
+
+#include <CoreAudio/CoreAudioTypes.h>
+#include <pthread.h>
+
+
+//=============================================================================
+//  CAGuard
+//
+//  This is your typical mutex with signalling implemented via pthreads.
+//  Lock() will return true if and only if the guard is locked on that call.
+//  A thread that already has the guard will receive 'false' if it locks it
+//  again. Use of the stack-based CAGuard::Locker class is highly recommended
+//  to properly manage the recursive nesting. The Wait calls with timeouts
+//  will return true if and only if the timeout period expired. They will
+//  return false if they receive notification any other way.
+//=============================================================================
+
+class   CAGuard
+{
+
+//  Construction/Destruction
+public:
+                    CAGuard();
+    virtual         ~CAGuard();
+
+//  Actions
+public:
+    virtual bool    Lock();
+    virtual void    Unlock();
+    virtual bool    Try(bool& outWasLocked);    // returns true if lock is free, false if not
+        
+    virtual void    Wait();
+    
+    virtual void    Notify();
+
+//  Implementation
+protected:
+    pthread_mutex_t mMutex;
+    pthread_cond_t  mCondVar;
+    pthread_t       mOwner;
+    
+//  Helper class to manage taking and releasing recursively
+public:
+    class           Locker
+    {
+    
+    //  Construction/Destruction
+    public:
+                    Locker(CAGuard& inGuard) : mGuard(inGuard), mNeedsRelease(false) { mNeedsRelease = mGuard.Lock(); }
+                    ~Locker() { if(mNeedsRelease) { mGuard.Unlock(); } }
+    
+    private:
+                    Locker(const Locker&);
+        Locker&     operator=(const Locker&);
+    
+    //  Actions
+    public:
+        void        Wait() { mGuard.Wait(); }
+        
+        void        Notify() { mGuard.Notify(); }
+
+    //  Implementation
+    private:
+        CAGuard&    mGuard;
+        bool        mNeedsRelease;
+    
+    };
+
+};
+
+#endif

src/cdrom/macosx/CDPlayer.h

+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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@libsdl.org
+*/
+
+#ifndef __CDPlayer__H__
+#define __CDPlayer__H__ 1
+
+#include <CoreFoundation/CoreFoundation.h>
+#include <Carbon/Carbon.h>
+
+#include <AudioUnit/AudioUnit.h>
+#include <AudioToolbox/AudioToolbox.h>
+
+#include <SDL.h>
+
+#include <string.h>
+#include <unistd.h> // for usleep
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void (*CDPlayerCompletionProc)(SDL_CD *cdrom) ;
+
+void     Lock ();
+
+void     Unlock();
+
+int      LoadFile (const FSRef *ref, int startFrame, int endFrame); // pass -1 to do nothing
+
+int      ReleaseFile ();
+
+int      PlayFile  ();
+
+int      PauseFile ();
+
+void     SetCompletionProc (CDPlayerCompletionProc proc, SDL_CD *cdrom);
+
+int      ReadTOCData (FSVolumeRefNum theVolume, SDL_CD *theCD);
+
+int      ListTrackFiles (FSVolumeRefNum theVolume, FSRef *trackFiles, int numTracks);
+
+int      DetectAudioCDVolumes (FSVolumeRefNum *volumes, int numVolumes);
+
+int      GetCurrentFrame ();
+
+#ifdef __cplusplus
+};
+#endif
+
+#endif /* __CD_Player__H__ */

src/cdrom/macosx/Makefile.am

+
+## Makefile.am for the Mac OS X cdrom driver for SDL
+
+noinst_LTLIBRARIES = libcdrom_macosx.la
+libcdrom_macosx_la_SOURCES = $(SRCS)
+
+# The SDL cdrom driver sources
+SRCS = \
+	SDL_syscdrom.c \
+	AudioFilePlayer.cpp \
+	AudioFileReaderThread.cpp \
+	CAGuard.cpp \
+	CDPlayer.cpp

src/cdrom/macosx/SDL_syscdrom_c.h

+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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@libsdl.org
+*/
+
+
+/***********************************************************************************
+ Implementation Notes
+ *********************
+
+    This code has several limitations currently (all of which are proabaly fixable):
+    
+    1. A CD-ROM device is inferred from a mounted cdfs volume, so device 0 is
+       not necessarily the first CD-ROM device on the system. (Somewhat easy to fix
+       by useing the device name from the volume id's to reorder the volumes)
+       
+    2. You can only open and control 1 CD-ROM device at a time. (Challenging to fix,
+       due to extensive code restructuring)
+    
+    3. The status reported by SDL_CDStatus only changes to from CD_PLAYING to CD_STOPPED in
+       1-second intervals (because the audio is buffered in 1-second chunks) If
+       the audio data is less than 1 second, the remainder is filled with silence.
+       
+       If you need to play sequences back-to-back that are less that 1 second long,
+       use the frame position to determine when to play the next sequence, instead
+       of SDL_CDStatus.
+       
+       This may be possible to fix with a clever usage of the AudioUnit API.
+       
+    4. When new volumes are inserted, our volume information is not updated. The only way
+       to refresh this information is to reinit the CD-ROM subsystem of SDL. To fix this,
+       one would probably have to fix point 1 above first, then figure out how to register
+       for a notification when new media is mounted in order to perform an automatic
+       rescan for cdfs volumes.
+    
+    
+    
+    So, here comes a description of how this all works.
+    
+        < Initializing >
+        
+        To get things rolling, we have to locate mounted volumes that contain
+        audio (since nearly all Macs don't have analog audio-in on the sound card).
+        That's easy, since these volumes have a flag that indicates this special
+        filesystem. See DetectAudioCDVolumes() in CDPlayer.cpp for this code.
+        
+        Next, we parse the invisible .TOC.plist in the root of the volume, which gets us
+        the track information (number, offset, length, leadout, etc). See ReadTOCData() in
+        CDPlayer.cpp for the skinny on this.
+        
+        
+        < The Playback Loop >
+        
+        Now come the tricky parts. Let's start with basic audio playback. When a frame
+        range to play is requested, we must first find the .aiff files on the volume, 
+        hopefully in the right order. Since these files all begin with a number "1 Audio Track", 
+        etc, this is used to determine the correct track order.
+        
+        Once all files are determined, we have to find what file corresponds to the start
+        and length parameter to SDL_SYS_CDPlay(). Again, this is quite simple by walking the
+        cdrom's track list. At this point, we also save the offset to the next track and frames
+        remaining, if we're going to have to play another file after the first one. See
+        GetFileForOffset() for this code.
+        
+        At this point we have all info needed to start playback, so we hand off to the LoadFile()
+        function, which proceeds to do its magic and plays back the file.
+        
+        When the file is finished playing, CompletionProc() is invoked, at which time we can
+        play the next file if the previously saved next track and frames remaining
+        indicates that we should. 
+        
+        
+        < Magic >
+        
+        OK, so it's not really magic, but since I don't fully understand all the hidden details it
+        seems like it to me ;-) The API's involved are the AudioUnit and AudioFile API's. These
+        appear to be an extension of CoreAudio for creating modular playback and f/x entities.
+        The important thing is that CPU usage is very low and reliability is very high. You'd
+        be hard-pressed to find a way to stutter the playback with other CPU-intensive tasks.
+    
+        One part of this magic is that it uses multiple threads, which carries the usual potential
+        for disaster if not handled carefully. Playback currently requires 4 additional threads:
+            1. The coreaudio runloop thread
+            2. The coreaudio device i/o thread
+            3. The file streaming thread
+            4. The notification/callback thread
+        
+        The first 2 threads are necessary evil - CoreAudio creates this no matter what the situation
+        is (even the SDL sound implementation creates theses suckers). The last two are are created
+        by us.
+        
+        The file is streamed from disk using a threaded double-buffer approach. 
+        This way, the high latency operation of reading from disk can be performed without interrupting
+        the real-time device thread (which amounts to avoiding dropouts). The device thread grabs the
+        buffer that isn't being read and sends it to the CoreAudio mixer where it eventually gets 
+        to the sound card.
+        
+        The device thread posts a notification when the file streaming thread is out of data. This
+        notification must be handled in a separate thread to avoid potential deadlock in the
+        device thread. That's where the notification thread comes in. This thread is signaled
+        whenever a notification needs to be processed, so another file can be played back if need be.
+        
+        The API in CDPlayer.cpp contains synchronization because otherwise both the notification thread
+        and main thread (or another other thread using the SDL CD api) can potentially call it at the same time.
+    
+************************************************************************************/
+
+
+#include "SDL_cdrom.h"
+#include "SDL_syscdrom.h"
+
+#include "CDPlayer.h"
+
+#define kErrorFakeDevice "Error: Cannot proceed since we're faking a CD-ROM device. Reinit the CD-ROM subsystem to scan for new volumes."
+

test/testcdrom.c

@@ -64,8 +64,8 @@ static void ListTracks(SDL_CD *cdrom)
 			trtype="unknown";
 			break;
 		}
-		printf("\tTrack (index %d) %d: %d:%2.2d [%s track]\n", i,
-					cdrom->track[i].id, m, s, trtype);
+		printf("\tTrack (index %d) %d: %d:%2.2d / %d [%s track]\n", i,
+					cdrom->track[i].id, m, s, cdrom->track[i].length, trtype);
 	}
 }