Retired Document
Important: This sample code may not represent best practices for current development. The project may use deprecated symbols and illustrate technologies and techniques that are no longer recommended.
Relevant replacement documents include:
AUPublic/AUBase/ComponentBase.h
/* |
File: ComponentBase.h |
Abstract: Part of CoreAudio Utility Classes |
Version: 1.1 |
Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple |
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 Apple's 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 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. |
Copyright (C) 2012 Apple Inc. All Rights Reserved. |
*/ |
#ifndef __ComponentBase_h__ |
#define __ComponentBase_h__ |
#include <new> |
#include "CADebugMacros.h" |
#include "CAXException.h" |
#if !defined(__COREAUDIO_USE_FLAT_INCLUDES__) |
#include <CoreAudio/CoreAudioTypes.h> |
#include <AudioUnit/AudioUnit.h> |
#if !CA_USE_AUDIO_PLUGIN_ONLY |
#include <CoreServices/../Frameworks/CarbonCore.framework/Headers/Components.h> |
#if (MAC_OS_X_VERSION_MAX_ALLOWED <= MAC_OS_X_VERSION_10_5) |
#define AudioComponentInstance ComponentInstance |
#define AudioComponentDescription ComponentDescription |
#define AudioComponent Component |
#endif |
Handle CMgr_GetComponentInstanceStorage(ComponentInstance aComponentInstance); |
void CMgr_SetComponentInstanceStorage(ComponentInstance aComponentInstance, Handle theStorage); |
#endif |
#if MAC_OS_X_VERSION_MAX_ALLOWED <= MAC_OS_X_VERSION_10_4 |
typedef Float32 AudioUnitParameterValue; |
#endif |
#if COREAUDIOTYPES_VERSION < 1051 |
typedef Float32 AudioUnitSampleType; |
#endif |
#if !TARGET_OS_WIN32 |
#include <pthread.h> |
#endif |
#if TARGET_OS_WIN32 |
#include "CAGuard.h" |
#endif |
#else |
#include "CoreAudioTypes.h" |
#if !CA_USE_AUDIO_PLUGIN_ONLY |
#include "ComponentManagerDependenciesWin.h" |
#endif |
#include "AudioUnit.h" |
#include "CAGuard.h" |
#endif |
#ifndef COMPONENT_THROW |
#if VERBOSE_COMPONENT_THROW |
#define COMPONENT_THROW(throw_err) \ |
do { DebugMessage(#throw_err); throw static_cast<OSStatus>(throw_err); } while (0) |
#else |
#define COMPONENT_THROW(throw_err) \ |
throw static_cast<OSStatus>(throw_err) |
#endif |
#endif |
#define COMPONENT_CATCH \ |
catch (const CAXException &ex) { result = ex.mError; } \ |
catch (std::bad_alloc &) { result = kAudio_MemFullError; } \ |
catch (OSStatus catch_err) { result = catch_err; } \ |
catch (OSErr catch_err) { result = catch_err; } \ |
catch (...) { result = -1; } |
/*! @class ComponentBase */ |
class ComponentBase { |
public: |
// classic MacErrors |
enum { noErr = 0}; |
/*! @ctor ComponentBase */ |
ComponentBase(AudioComponentInstance inInstance); |
/*! @dtor ~ComponentBase */ |
virtual ~ComponentBase(); |
/*! @method PostConstructor */ |
virtual void PostConstructor(); |
/*! @method PreDestructor */ |
virtual void PreDestructor(); |
#if !CA_USE_AUDIO_PLUGIN_ONLY |
/*! @method Version */ |
virtual OSStatus Version(); |
/*! @method ComponentEntryDispatch */ |
static OSStatus ComponentEntryDispatch(ComponentParameters *p, ComponentBase *This); |
/*! GetSelectorForCanDo */ |
static SInt16 GetSelectorForCanDo(ComponentParameters *params); |
#endif |
/*! @method GetComponentInstance */ |
AudioComponentInstance GetComponentInstance() const { return mComponentInstance; } |
/*! @method GetComponentDescription */ |
AudioComponentDescription GetComponentDescription() const; |
// This global variable is so that new instances know how they were instantiated: via the Component Manager, |
// or as AudioComponents. It's ugly, but preferable to altering the constructor of every class in the hierarchy. |
// It's safe because construction is protected by ComponentInitLocker. |
enum EInstanceType { kComponentMgrInstance, kAudioComponentInstance }; |
static EInstanceType sNewInstanceType; |
/*! @method IsPluginObject */ |
bool IsPluginObject () const { return mInstanceType == kAudioComponentInstance; } |
/*! @method IsCMgrObject */ |
bool IsCMgrObject () const { return mInstanceType == kComponentMgrInstance; } |
/*! @method AP_Open */ |
static OSStatus AP_Open(void *self, AudioUnit compInstance); |
/*! @method AP_Close */ |
static OSStatus AP_Close(void *self); |
protected: |
/*! @var mComponentInstance */ |
AudioComponentInstance mComponentInstance; |
EInstanceType mInstanceType; |
}; |
class ComponentInitLocker |
{ |
#if TARGET_OS_MAC |
public: |
ComponentInitLocker() |
{ |
pthread_once(&sOnce, InitComponentInitLocker); |
pthread_mutex_lock(&sComponentOpenMutex); |
mPreviousNewInstanceType = ComponentBase::sNewInstanceType; |
} |
~ComponentInitLocker() |
{ |
ComponentBase::sNewInstanceType = mPreviousNewInstanceType; |
pthread_mutex_unlock(&sComponentOpenMutex); |
} |
private: |
static pthread_mutex_t sComponentOpenMutex; |
static pthread_once_t sOnce; |
static void InitComponentInitLocker(); |
#elif TARGET_OS_WIN32 |
public: |
bool sNeedsUnlocking; |
ComponentInitLocker() { sNeedsUnlocking = sComponentOpenGuard.Lock(); } |
~ComponentInitLocker() { if(sNeedsUnlocking) { sComponentOpenGuard.Unlock(); } } |
private: |
static CAGuard sComponentOpenGuard; |
#endif |
private: |
ComponentBase::EInstanceType mPreviousNewInstanceType; |
}; |
/*! @class AudioComponentPlugInInstance */ |
struct AudioComponentPlugInInstance { |
AudioComponentPlugInInterface mPlugInInterface; |
void * (*mConstruct)(void *memory, AudioComponentInstance ci); |
void (*mDestruct)(void *memory); |
void * mPad[2]; // pad to a 16-byte boundary (in either 32 or 64 bit mode) |
UInt32 mInstanceStorage; // the ACI implementation object is constructed into this memory |
// this member is just a placeholder. it is aligned to a 16byte boundary |
}; |
/*! @class APFactory */ |
template <class APMethodLookup, class Implementor> |
class APFactory { |
public: |
static void *Construct(void *memory, AudioComponentInstance compInstance) |
{ |
return new(memory) Implementor(compInstance); |
} |
static void Destruct(void *memory) |
{ |
((Implementor *)memory)->~Implementor(); |
} |
// This is the AudioComponentFactoryFunction. It returns an AudioComponentPlugInInstance. |
// The actual implementation object is not created until Open(). |
static AudioComponentPlugInInterface *Factory(const AudioComponentDescription *inDesc) |
{ |
AudioComponentPlugInInstance *acpi = |
(AudioComponentPlugInInstance *)malloc( offsetof(AudioComponentPlugInInstance, mInstanceStorage) + sizeof(Implementor) ); |
acpi->mPlugInInterface.Open = ComponentBase::AP_Open; |
acpi->mPlugInInterface.Close = ComponentBase::AP_Close; |
acpi->mPlugInInterface.Lookup = APMethodLookup::Lookup; |
acpi->mPlugInInterface.reserved = NULL; |
acpi->mConstruct = Construct; |
acpi->mDestruct = Destruct; |
acpi->mPad[0] = NULL; |
acpi->mPad[1] = NULL; |
return (AudioComponentPlugInInterface*)acpi; |
} |
// This is for runtime registration (not for plug-ins loaded from bundles). |
static AudioComponent Register(UInt32 type, UInt32 subtype, UInt32 manuf, CFStringRef name, UInt32 vers, UInt32 flags=0) |
{ |
AudioComponentDescription desc = { type, subtype, manuf, flags, 0 }; |
return AudioComponentRegister(&desc, name, vers, Factory); |
} |
}; |
#if !CA_USE_AUDIO_PLUGIN_ONLY |
/*! @class ComponentEntryPoint |
* @discussion This is only used for a component manager version |
*/ |
template <class Class> |
class ComponentEntryPoint { |
public: |
/*! @method Dispatch */ |
static OSStatus Dispatch(ComponentParameters *params, Class *obj) |
{ |
OSStatus result = noErr; |
try { |
if (params->what == kComponentOpenSelect) { |
// solve a host of initialization thread safety issues. |
ComponentInitLocker lock; |
ComponentBase::sNewInstanceType = ComponentBase::kComponentMgrInstance; |
ComponentInstance ci = (ComponentInstance)(params->params[0]); |
Class *This = new Class((AudioComponentInstance)ci); |
This->PostConstructor(); // allows base class to do additional initialization |
// once the derived class is fully constructed |
CMgr_SetComponentInstanceStorage(ci, (Handle)This); |
} else |
result = Class::ComponentEntryDispatch(params, obj); |
} |
COMPONENT_CATCH |
return result; |
} |
/*! @method Register */ |
static Component Register(OSType compType, OSType subType, OSType manufacturer) |
{ |
ComponentDescription description = {compType, subType, manufacturer, 0, 0}; |
Component component = RegisterComponent(&description, (ComponentRoutineUPP) Dispatch, registerComponentGlobal, NULL, NULL, NULL); |
if (component != NULL) { |
SetDefaultComponent(component, defaultComponentAnyFlagsAnyManufacturerAnySubType); |
} |
return component; |
} |
}; |
// these are the macros that are used to generate the Entry Points for a given Audio Plugin |
#if CA_USE_AUDIO_PLUGIN_ONLY |
#define AUDIOCOMPONENT_ENTRY(FactoryType, Class) \ |
extern "C" void * Class##Factory(const AudioComponentDescription *inDesc); \ |
extern "C" void * Class##Factory(const AudioComponentDescription *inDesc) { \ |
return FactoryType<Class>::Factory(inDesc); \ |
} |
#else |
// you should be using this macros as it registers both |
// a plugin and a component mgr version. this can and should be used |
// with new and existing audio components (backwards compatible to SL) |
#define AUDIOCOMPONENT_ENTRY(FactoryType, Class) \ |
extern "C" OSStatus Class##Entry(ComponentParameters *params, Class *obj); \ |
extern "C" OSStatus Class##Entry(ComponentParameters *params, Class *obj) { \ |
return ComponentEntryPoint<Class>::Dispatch(params, obj); \ |
} \ |
extern "C" void * Class##Factory(const AudioComponentDescription *inDesc); \ |
extern "C" void * Class##Factory(const AudioComponentDescription *inDesc) { \ |
return FactoryType<Class>::Factory(inDesc); \ |
} |
// the only component we still support are the carbon based view components |
// you should be using this macro now to exclusively register those types |
#define VIEW_COMPONENT_ENTRY(Class) \ |
extern "C" OSStatus Class##Entry(ComponentParameters *params, Class *obj); \ |
extern "C" OSStatus Class##Entry(ComponentParameters *params, Class *obj) { \ |
return ComponentEntryPoint<Class>::Dispatch(params, obj); \ |
} |
#endif |
/*! @class ComponentRegistrar */ |
template <class Class, OSType Type, OSType Subtype, OSType Manufacturer> |
class ComponentRegistrar { |
public: |
/*! @ctor ComponentRegistrar */ |
ComponentRegistrar() { ComponentEntryPoint<Class>::Register(Type, Subtype, Manufacturer); } |
}; |
#define COMPONENT_REGISTER(Class,Type,Subtype,Manufacturer) \ |
static ComponentRegistrar<Class, Type, Subtype, Manufacturer> gRegistrar##Class |
#else |
#define COMPONENT_ENTRY(Class) |
#define COMPONENT_REGISTER(Class) |
#define AUDIOCOMPONENT_ENTRY(FactoryType, Class) |
#endif // !CA_USE_AUDIO_PLUGIN_ONLY |
#endif // __ComponentBase_h__ |
Copyright © 2012 Apple Inc. All Rights Reserved. Terms of Use | Privacy Policy | Updated: 2012-10-16