isc::hooks::PointerConverter Class Reference

Local class for conversion of void pointers to function pointers. More...

#include <pointer_converter.h>

Public Member Functions
	PointerConverter (void *dlsym_ptr)
	Constructor. More...
	PointerConverter (CalloutPtr callout_ptr)
	Constructor. More...
Pointer accessor functions
It is up to the caller to ensure that the correct member is called so that the correct type of pointer is returned.
void *	dlsymPtr () const
	Return pointer returned by dlsym call. More...
CalloutPtr	calloutPtr () const
	Return pointer to callout function. More...
load_function_ptr	loadPtr () const
	Return pointer to load function. More...
unload_function_ptr	unloadPtr () const
	Return pointer to unload function. More...
version_function_ptr	versionPtr () const
	Return pointer to version function. More...
multi_threading_compatible_function_ptr	multiThreadingCompatiblePtr () const
	Return pointer to multi_threading_compatible function. More...

Detailed Description

Local class for conversion of void pointers to function pointers.

Converting between void* and function pointers in C++ is fraught with difficulty and pitfalls, e.g. see https://groups.google.com/forum/?hl=en&fromgroups#!topic/comp.lang.c++/37o0l8rtEE0

The method given in that article - convert using a union is used here. A union is declared (and zeroed) and the appropriate member extracted when needed.

Definition at line 25 of file pointer_converter.h.

Constructor & Destructor Documentation

isc::hooks::PointerConverter::PointerConverter ( void *  dlsym_ptr )

inline

Constructor.

Zeroes the union and stores the void* pointer we wish to convert (the one returned by dlsym).

Parameters

dlsym_ptr

void* pointer returned by call to dlsym()

Definition at line 33 of file pointer_converter.h.

References dlsym_ptr.

isc::hooks::PointerConverter::PointerConverter ( CalloutPtr  callout_ptr )

inline

Constructor.

Zeroes the union and stores the CalloutPtr pointer we wish to convert. This constructor is used in debug messages; output of a pointer to an object (including to a function) is, on some compilers, printed as "1".

Parameters

callout_ptr

Pointer to callout function

Definition at line 46 of file pointer_converter.h.

References callout_ptr.

Member Function Documentation

CalloutPtr isc::hooks::PointerConverter::calloutPtr ( ) const

inline

Return pointer to callout function.

Returns

Pointer to the callout function

Definition at line 70 of file pointer_converter.h.

Referenced by isc::hooks::LibraryManager::registerStandardCallouts().

void* isc::hooks::PointerConverter::dlsymPtr ( ) const

inline

Return pointer returned by dlsym call.

Returns

void* pointer returned by the call to dlsym(). This can be used in statements that print the hexadecimal value of the symbol.

Definition at line 63 of file pointer_converter.h.

Referenced by isc::hooks::CalloutManager::callCallouts().

load_function_ptr isc::hooks::PointerConverter::loadPtr ( ) const

inline

Return pointer to load function.

Returns

Pointer to the load function

Definition at line 77 of file pointer_converter.h.

Referenced by isc::hooks::LibraryManager::runLoad().

multi_threading_compatible_function_ptr isc::hooks::PointerConverter::multiThreadingCompatiblePtr ( ) const

inline

Return pointer to multi_threading_compatible function.

Returns

Pointer to the multi_threading_compatible function

Definition at line 98 of file pointer_converter.h.

Referenced by isc::hooks::LibraryManager::checkMultiThreadingCompatible().

unload_function_ptr isc::hooks::PointerConverter::unloadPtr ( ) const

inline

Return pointer to unload function.

Returns

Pointer to the unload function

Definition at line 84 of file pointer_converter.h.

Referenced by isc::hooks::LibraryManager::prepareUnloadLibrary().

version_function_ptr isc::hooks::PointerConverter::versionPtr ( ) const

inline

Return pointer to version function.

Returns

Pointer to the version function

Definition at line 91 of file pointer_converter.h.

Referenced by isc::hooks::LibraryManager::checkVersion().

Member Data Documentation

CalloutPtr isc::hooks::PointerConverter::callout_ptr

Definition at line 109 of file pointer_converter.h.

Referenced by PointerConverter().

void* isc::hooks::PointerConverter::dlsym_ptr

Definition at line 108 of file pointer_converter.h.

Referenced by PointerConverter().

load_function_ptr isc::hooks::PointerConverter::load_ptr

Definition at line 110 of file pointer_converter.h.

multi_threading_compatible_function_ptr isc::hooks::PointerConverter::multi_threading_compatible_ptr

Definition at line 113 of file pointer_converter.h.

unload_function_ptr isc::hooks::PointerConverter::unload_ptr

Definition at line 111 of file pointer_converter.h.

version_function_ptr isc::hooks::PointerConverter::version_ptr

Definition at line 112 of file pointer_converter.h.

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The documentation for this class was generated from the following file:

• pointer_converter.h