Elfspy/Fake.h

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2016-09-16 17:45:35 +02:00
#ifndef ELFSPY_FAKE_H
#define ELFSPY_FAKE_H
#include "elfspy/Lambda.h"
namespace spy
{
/**
* @namespace spy
* @class Fake
* This replaces an existing function with another function, so that all calls
* to the program are made to the other function.
* The constructor installs the new function in place of the function, the
* destructor uninstalls it
*/
template <typename H, typename ReturnType, typename... ArgTypes>
class Fake
{
public:
Fake(H& hook, ReturnType (*func)(ArgTypes...));
~Fake();
private:
H& hook_;
ReturnType (*func_)(ArgTypes...);
};
template <typename H, typename ReturnType, typename... ArgTypes>
inline Fake<H, ReturnType, ArgTypes...>::
Fake(H& hook, ReturnType (*func)(ArgTypes...))
:hook_(hook)
{
func_ = hook_.patch(func);
}
template <typename H, typename ReturnType, typename... ArgTypes>
inline Fake<H, ReturnType, ArgTypes...>::~Fake()
{
hook_.patch(func_);
}
template <typename H, typename ReturnType, typename... ArgTypes>
inline auto fake(H& hook, ReturnType (*patch)(ArgTypes...))
-> Fake<H, ReturnType, ArgTypes...>
{
return { hook, patch };
}
template <typename H, typename ReturnType, typename... ArgTypes>
inline auto new_fake(H& hook, ReturnType (*patch)(ArgTypes...))
-> Fake<H, ReturnType, ArgTypes...>*
{
return new Fake<H, ReturnType, ArgTypes...>(hook, patch);
}
} // namespace elfspy
#endif