livetrax/libs/appleutility/CoreAudio/PublicUtility/CASharedLibrary.cpp

/*
     File: CASharedLibrary.cpp
 Abstract: CASharedLibrary.h
  Version: 1.1
 
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 license, under Apple's copyrights in this original Apple software (the
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 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
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 The Apple Software is provided by Apple on an "AS IS" basis.  APPLE
 MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION
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 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
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*/
//=============================================================================
//	Includes
//=============================================================================

#include "CASharedLibrary.h"

//#define	CASharedLibrary_Use_DYLD	1
#if	CASharedLibrary_Use_DYLD
	#include <mach-o/dyld.h>
#else
	#include <dlfcn.h>
	#include <stddef.h>
#endif

//=============================================================================
//	CASharedLibrary
//=============================================================================

void*	CASharedLibrary::LoadLibraryAndGetRoutineAddress(const char* inRoutineName, const char* /*inLibraryName*/, const char* inLibraryPath)
{
	void* theRoutine = 0;

#if	CASharedLibrary_Use_DYLD
	const struct mach_header* theImage = NSAddImage(inLibraryPath, NSADDIMAGE_OPTION_RETURN_ON_ERROR);
	if(theImage != 0)
	{
		NSSymbol theSymbol = NSLookupSymbolInImage(theImage, inRoutineName, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND);
		if(theSymbol != 0)
		{
			theRoutine = NSAddressOfSymbol(theSymbol);
		}
	}
#else
	void* theImage = dlopen(inLibraryPath, RTLD_LAZY);
	if(theImage != NULL)
	{
		//	we assume that all routine names passed here have a leading underscore which gets shaved
		//	off when passed to dlsym
		theRoutine = dlsym(theImage, &(inRoutineName[1]));
	}
	
#endif

	return theRoutine;
}

void*	CASharedLibrary::GetRoutineAddressIfLibraryLoaded(const char* inRoutineName, const char* /*inLibraryName*/, const char* inLibraryPath)
{
	void* theRoutine = 0;
		
#if	CASharedLibrary_Use_DYLD
	const struct mach_header* theImage = NSAddImage(inLibraryPath, NSADDIMAGE_OPTION_RETURN_ONLY_IF_LOADED);
	if(theImage != 0)
	{
		NSSymbol theSymbol = NSLookupSymbolInImage(theImage, inRoutineName, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND);
		if(theSymbol != 0)
		{
			theRoutine = NSAddressOfSymbol(theSymbol);
		}
	}
#else
	void* theImage = dlopen(inLibraryPath, RTLD_LAZY | RTLD_NOLOAD);
	if(theImage != NULL)
	{
		//	we assume that all routine names passed here have a leading underscore which gets shaved
		//	off when passed to dlsym
		theRoutine = dlsym(theImage, &(inRoutineName[1]));
	}
#endif

	return theRoutine;
}