Elfspy/GOTEntry.h
2016-09-17 22:46:34 +02:00

96 lines
2.2 KiB
C++

#ifndef ELFSPY_GOTENTRY_H
#define ELFSPY_GOTENTRY_H
#include <typeinfo>
#include <vector>
#include "elfspy/MethodPointer.h"
namespace spy
{
/**
* @namespace spy
* @class GOTEntry
* Handle a function of interest and all its references in all Global Offset
* Tables
*/
class GOTEntry
{
public:
GOTEntry() = default;
/**
* @param function address of function
* @param name name of function
* @return original unaltered address of function
*/
void* set(void* function, const char* name);
/**
* replace function with other function and reference count
* @param function to enter in Global Offset Tables instead of original
* @return original entry in Global Offset Table instead of original
*/
void* spy_with(void* function);
/**
* count down reference count from spy_with and restore original entry in
* Global Offset Tables if count is zero
*/
void restore();
/**
* replace function with other function
* @param function to enter in Global Offset Tables instead of original
* @return original entry in Global Offset Table instead of original
*/
void* patch(void* function);
/**
* get the address of a virtual function
* @param type type info of class
* @param method method function pointer
* @return address of address of virtual function for that class
*/
static void** get_vtable_entry(const std::type_info& type,
const MethodPointer& method);
static void initialise(int argc, char** argv);
const void* current() const;
const void* original() const;
/**
* add an entry to the function pointer addresses
* @param address address of address of function
*/
void make_entry(void** address);
private:
struct Entry
{
void** address_;
void* restore_;
};
std::vector<Entry> entries_; // all entries
size_t spy_count_ = 0;
void* current_ = nullptr;
void* original_ = nullptr;
void make_entry(unsigned char* address);
};
inline const void* GOTEntry::current() const
{
return original_;
}
inline const void* GOTEntry::original() const
{
return original_;
}
inline void GOTEntry::make_entry(unsigned char* address)
{
make_entry(reinterpret_cast<void**>(address));
}
} // namespace spy
#endif