1 /*
2      File: CASharedLibrary.cpp
3  Abstract: CASharedLibrary.h
4   Version: 1.1
5 
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46 */
47 //=============================================================================
48 //	Includes
49 //=============================================================================
50 
51 #include "CASharedLibrary.h"
52 
53 //#define	CASharedLibrary_Use_DYLD	1
54 #if	CASharedLibrary_Use_DYLD
55 	#include <mach-o/dyld.h>
56 #else
57 	#include <dlfcn.h>
58 	#include <stddef.h>
59 #endif
60 
61 //=============================================================================
62 //	CASharedLibrary
63 //=============================================================================
64 
LoadLibraryAndGetRoutineAddress(const char * inRoutineName,const char *,const char * inLibraryPath)65 void*	CASharedLibrary::LoadLibraryAndGetRoutineAddress(const char* inRoutineName, const char* /*inLibraryName*/, const char* inLibraryPath)
66 {
67 	void* theRoutine = 0;
68 
69 #if	CASharedLibrary_Use_DYLD
70 	const struct mach_header* theImage = NSAddImage(inLibraryPath, NSADDIMAGE_OPTION_RETURN_ON_ERROR);
71 	if(theImage != 0)
72 	{
73 		NSSymbol theSymbol = NSLookupSymbolInImage(theImage, inRoutineName, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND);
74 		if(theSymbol != 0)
75 		{
76 			theRoutine = NSAddressOfSymbol(theSymbol);
77 		}
78 	}
79 #else
80 	void* theImage = dlopen(inLibraryPath, RTLD_LAZY);
81 	if(theImage != NULL)
82 	{
83 		//	we assume that all routine names passed here have a leading underscore which gets shaved
84 		//	off when passed to dlsym
85 		theRoutine = dlsym(theImage, &(inRoutineName[1]));
86 	}
87 
88 #endif
89 
90 	return theRoutine;
91 }
92 
GetRoutineAddressIfLibraryLoaded(const char * inRoutineName,const char *,const char * inLibraryPath)93 void*	CASharedLibrary::GetRoutineAddressIfLibraryLoaded(const char* inRoutineName, const char* /*inLibraryName*/, const char* inLibraryPath)
94 {
95 	void* theRoutine = 0;
96 
97 #if	CASharedLibrary_Use_DYLD
98 	const struct mach_header* theImage = NSAddImage(inLibraryPath, NSADDIMAGE_OPTION_RETURN_ONLY_IF_LOADED);
99 	if(theImage != 0)
100 	{
101 		NSSymbol theSymbol = NSLookupSymbolInImage(theImage, inRoutineName, NSLOOKUPSYMBOLINIMAGE_OPTION_BIND);
102 		if(theSymbol != 0)
103 		{
104 			theRoutine = NSAddressOfSymbol(theSymbol);
105 		}
106 	}
107 #else
108 	void* theImage = dlopen(inLibraryPath, RTLD_LAZY | RTLD_NOLOAD);
109 	if(theImage != NULL)
110 	{
111 		//	we assume that all routine names passed here have a leading underscore which gets shaved
112 		//	off when passed to dlsym
113 		theRoutine = dlsym(theImage, &(inRoutineName[1]));
114 	}
115 #endif
116 
117 	return theRoutine;
118 }
119