mirror of
https://github.com/alliedmodders/metamod-source.git
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Initial draft: Templated SourceHook
Introduces one massive template for generating SourceHook managers. The goal is for this to simplify the definition of SourceHooks long-term by replacing macros with templates. This introduces some new templates for metaprogramming, but they're hidden away in the SourceHook::metaprogramming namespace. Tested on Windows 32 bit and Linux 32 bit TF2.
This commit is contained in:
Mooshua
parent
b4aa055dea
commit
aa88f23880
@ -98,8 +98,10 @@
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#ifdef _MSC_VER
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# define SH_COMP SH_COMP_MSVC
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# define SH_INLINE inline __forceinline
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#elif defined __GNUC__
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# define SH_COMP SH_COMP_GCC
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# define SH_INLINE inline __attribute__((always_inline))
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#else
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# error Unsupported compiler
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#endif
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@ -114,6 +116,7 @@
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#define SH_PTRSIZE sizeof(void*)
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#include <type_traits>
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#include "sh_memfuncinfo.h"
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#include "FastDelegate.h"
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@ -566,6 +569,434 @@ namespace SourceHook
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static const int type = 0;
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static const unsigned int flags = PassInfo::PassFlag_ByRef;
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};
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/************************************************************************/
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/* Templated hook definition */
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/************************************************************************/
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namespace metaprogramming
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{
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namespace detail
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{
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/**
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* @brief Iterate over all elements of a type pack
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*
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* @param functor A reference to the functor containing the step<index, now> template.
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*/
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template<class Functor, int Index, typename Now, typename... Rest>
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constexpr SH_INLINE void for_each_template_impl(Functor *f)
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{
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f->template step<Index, Now>();
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if constexpr (sizeof...(Rest) > 0) {
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for_each_template_impl<Functor, Index + 1, Rest...>(f);
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}
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}
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}
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template<class Functor, typename First, typename... Rest>
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constexpr SH_INLINE void for_each_template(Functor* f)
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{
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detail::for_each_template_impl<Functor, 0, First, Rest...>(f);
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}
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/**
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* @brief Iterate over all elements of a type pack
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*
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* @param functor A reference to the functor containing the step<index, now> template.
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*/
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template<class Functor, typename First, typename... Rest>
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constexpr SH_INLINE void for_each_template_nullable(Functor* f)
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{
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for_each_template<Functor, First, Rest...>(f);
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}
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template<class Functor>
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constexpr SH_INLINE void for_each_template_nullable(Functor* f)
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{
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// Empty varargs
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}
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template <bool Test, class Yes = void, class No = void>
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struct if_else {
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public:
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typedef No type;
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};
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template <class Yes, class No>
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struct if_else<true, Yes, No> {
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public:
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typedef Yes type;
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};
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}
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namespace detail
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{
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/**
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* @brief Build the PassInfo for a method pack.
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*
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* Iterated over using for_each_template_nullable.
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*/
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class PrototypeBuilderFunctor
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{
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public:
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constexpr PrototypeBuilderFunctor(PassInfo* p)
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: params(p) {}
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PassInfo* params;
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template<int Index, typename Now>
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constexpr void step()
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{
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// Note: first index is always the thisptr!
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params[Index + 1] = { sizeof(Now), ::SourceHook::GetPassInfo< Now >::type, ::SourceHook::GetPassInfo< Now >::flags };
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}
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};
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/**
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* @brief Common type for the void/non-void handling semantics.
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*
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* Basically, *(void*) is an illegal operation as it works on zero-sized
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* types. We work around this here by using these two lovely templates,
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* which both specify safe handling for void and non-void return params.
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*
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* Invoke - call the passed delegate and safely handle the return type
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* Original - call the original method and safely handle the return type
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* Dereference - dereference the return type pointer for hook return semantics
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*
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*/
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template<ISourceHook** SourceHook, typename Result, typename... Args>
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struct BaseMethodInvoker
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{
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public:
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typedef Result (EmptyClass::*EmptyDelegate)(Args...);
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};
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template<ISourceHook** SourceHook, typename IDelegate, typename... Args>
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struct VoidMethodInvoker
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{
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public:
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typedef std::bool_constant<false> has_return;
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typedef BaseMethodInvoker<SourceHook, void, Args...> base;
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static void Invoke(IDelegate* delegate, void* result, Args... args)
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{
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// Do not touch return type: It's void!
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delegate->Call(args...);
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}
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static void Original(EmptyClass* self, typename base::EmptyDelegate mfp, void* result, Args... args)
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{
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// Do not touch return type: It's void!
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(self->*mfp)(args...);
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}
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static void Dereference(const void* arg)
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{
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return;
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}
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};
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template<ISourceHook** SourceHook, typename IDelegate, typename Result, typename... Args>
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struct ReturningMethodInvoker
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{
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public:
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typedef std::bool_constant<true> has_return;
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typedef BaseMethodInvoker<SourceHook, Result, Args...> base;
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static void Invoke(IDelegate* delegate, Result* result, Args... args)
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{
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*result = delegate->Call(args...);
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}
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static void Original(EmptyClass* self, typename base::EmptyDelegate mfp, Result* result, Args... args)
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{
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*result = (self->*mfp)(args...);
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}
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static Result Dereference(const Result* arg)
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{
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return *arg;
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}
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};
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}
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/**
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* @brief A hook manager, used to hook instances of a specific interface.
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*
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* You must specify the SourceHook pointer, interface, method pointer,
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* and prototype in the template arguments. Any derived class of the interface
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* can be hooked using this manager.
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*/
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template<ISourceHook** SH, typename Interface, auto Method, typename Result, typename... Args>
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struct Hook
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{
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/**
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* @brief The type we expect the template arg "Method" to be.
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*/
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typedef Result (Interface::*MemberMethod)(Args...);
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typedef fastdelegate::FastDelegate<Result, Args...> Delegate;
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typedef decltype(Method) MethodType;
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static_assert( std::is_same<MethodType, MemberMethod>::type::value, "Mismatched template parameters!" );
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// Members
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::SourceHook::MemFuncInfo MFI;
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::SourceHook::IHookManagerInfo *HI;
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::SourceHook::ProtoInfo Proto;
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// Singleton instance
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// Initialized below!
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static Hook Instance;
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private:
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Hook(Hook& other) = delete;
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/**
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* @brief Build the ProtoInfo for this hook
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*/
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constexpr Hook()
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{
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// build protoinfo
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Proto.numOfParams = sizeof...(Args);
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Proto.convention = ProtoInfo::CallConv_Unknown;
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if constexpr (std::is_void_v<Result>) {
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Proto.retPassInfo = {0, 0, 0};
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} else {
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Proto.retPassInfo = { sizeof(Result), ::SourceHook::GetPassInfo< Result >::type, ::SourceHook::GetPassInfo< Result >::flags };
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}
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// Iterate over the args... type pack
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auto paramsPassInfo = new PassInfo[sizeof...(Args) + 1];
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paramsPassInfo[0] = { 1, 0, 0 };
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Proto.paramsPassInfo = paramsPassInfo;
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detail::PrototypeBuilderFunctor argsBuilder(paramsPassInfo);
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metaprogramming::for_each_template_nullable<detail::PrototypeBuilderFunctor, Args...>(&argsBuilder);
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// Build the backwards compatible paramsPassInfoV2 field
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Proto.retPassInfo2 = {0, 0, 0, 0};
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auto paramsPassInfo2 = new PassInfo::V2Info[sizeof...(Args) + 1];
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Proto.paramsPassInfo2 = paramsPassInfo2;
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for (int i = 0; i /* lte to include thisptr! */ <= sizeof...(Args); ++i) {
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paramsPassInfo2[i] = { 0, 0, 0, 0 };
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}
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}
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public:
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static constexpr Hook* Make()
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{
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Hook::Instance = Hook();
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return &Hook::Instance;
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}
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public: // Public Interface
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/**
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* @brief Add an instance of this hook to the specified interface
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*
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* @param id the g_PLID value for the plugin creating the hook
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* @param iface the interface pointer to hook
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* @param post true when post-hooking, false when pre-hooking.
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* @param handler the handler that will be called in place of the original method
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* @param mode the hook mode - Hook_Normal will only hook this instance, while others alter the global virtual table.
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*/
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int Add(Plugin id, Interface* iface, bool post, Delegate handler, ::SourceHook::ISourceHook::AddHookMode mode = ISourceHook::AddHookMode::Hook_Normal)
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{
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using namespace ::SourceHook;
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MemFuncInfo mfi = {true, -1, 0, 0};
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GetFuncInfo(Method, mfi);
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if (mfi.thisptroffs < 0 || !mfi.isVirtual)
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return false;
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CMyDelegateImpl* delegate = new CMyDelegateImpl(handler);
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return (*SH)->AddHook(id, mode, iface, mfi.thisptroffs, Hook::HookManPubFunc, delegate, post);
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}
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/**
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* @brief Remove an existing hook handler from this interface
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*
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* @param id the g_PLID value for the plugin the hook was created under
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* @param iface the interface to be unhooked
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* @param post true if this was a post hook, false otherwise (pre-hook)
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* @param handler the handler that will be removed from this hook.
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*/
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int Remove(Plugin id, Interface* iface, bool post, Delegate handler)
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{
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using namespace ::SourceHook;
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MemFuncInfo mfi = {true, -1, 0, 0};
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GetFuncInfo(Method, mfi);
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// Temporary delegate for .IsEqual() comparison.
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CMyDelegateImpl temp(handler);
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return (*SH)->RemoveHook(id, iface, mfi.thisptroffs, Hook::HookManPubFunc, &temp, post);
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}
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protected:
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static int HookManPubFunc(bool store, ::SourceHook::IHookManagerInfo *hi)
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{
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// Build the MemberFuncInfo for the hooked method
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GetFuncInfo<MemberMethod>(static_cast<MemberMethod>(Method), Instance.MFI);
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if ((*SH)->GetIfaceVersion() != SH_IFACE_VERSION || (*SH)->GetImplVersion() < SH_IMPL_VERSION)
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return 1;
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if (store)
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Instance.HI = hi;
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if (hi) {
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// Build a memberfuncinfo for our hook processor.
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MemFuncInfo our_mfi = {true, -1, 0, 0};
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GetFuncInfo(&Hook::Func, our_mfi);
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void* us = reinterpret_cast<void **>(reinterpret_cast<char *>(&Instance) + our_mfi.vtbloffs)[our_mfi.vtblindex];
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hi->SetInfo(SH_HOOKMAN_VERSION, Instance.MFI.vtbloffs, Instance.MFI.vtblindex, &Instance.Proto, us);
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}
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return 0;
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}
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struct IMyDelegate : ::SourceHook::ISHDelegate
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{
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virtual Result Call(Args... args) = 0;
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};
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struct CMyDelegateImpl : IMyDelegate
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{
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Delegate _delegate;
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CMyDelegateImpl(Delegate deleg) : _delegate(deleg)
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{}
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virtual~CMyDelegateImpl() {}
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Result Call(Args... args) { return _delegate(args...); }
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void DeleteThis() { delete this; }
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bool IsEqual(ISHDelegate *pOtherDeleg) { return _delegate == static_cast<CMyDelegateImpl *>(pOtherDeleg)->_delegate; }
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};
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protected:
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/**
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* @brief An object containing methods to safely handle the return type
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*
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* This allows us to safely handle zero-sized types as return values.
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*/
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typedef typename metaprogramming::if_else<
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std::is_void<Result>::value,
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detail::VoidMethodInvoker<SH, IMyDelegate, Args...>,
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detail::ReturningMethodInvoker<SH, IMyDelegate, Result, Args...>
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>::type Invoker;
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/**
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* @brief An object containing a safely-allocatable return type
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*
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* Used when stack-allocating the return type;
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* void returns are never written to so using void* is safe.
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* when the return is not zero-sized, use the return itself.
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*/
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typedef typename metaprogramming::if_else<
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std::is_void<Result>::value,
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void*,
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Result
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>::type VoidSafeResult;
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typedef typename ReferenceCarrier<VoidSafeResult>::type ResultType;
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/**
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* @brief Hook handler virtual
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*/
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virtual Result Func(Args... args)
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{
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using namespace ::SourceHook;
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void *ourvfnptr = reinterpret_cast<void *>(
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*reinterpret_cast<void ***>(reinterpret_cast<char *>(this) + Instance.MFI.vtbloffs) + Instance.MFI.vtblindex);
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void *vfnptr_origentry;
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META_RES status = MRES_IGNORED;
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META_RES prev_res;
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META_RES cur_res;
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ResultType original_ret;
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ResultType override_ret;
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ResultType current_ret;
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IMyDelegate *iter;
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IHookContext *context = (*SH)->SetupHookLoop(
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Instance.HI,
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ourvfnptr,
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reinterpret_cast<void *>(this),
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&vfnptr_origentry,
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&status,
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&prev_res,
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&cur_res,
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&original_ret,
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&override_ret);
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// Call all pre-hooks
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prev_res = MRES_IGNORED;
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while ((iter = static_cast<IMyDelegate *>(context->GetNext()))) {
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cur_res = MRES_IGNORED;
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Invoker::Invoke(iter, ¤t_ret, args...);
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prev_res = cur_res;
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if (cur_res > status)
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status = cur_res;
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if (cur_res >= MRES_OVERRIDE)
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*reinterpret_cast<ResultType *>(context->GetOverrideRetPtr()) = current_ret;
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}
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// Call original method
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if (status != MRES_SUPERCEDE && context->ShouldCallOrig()) {
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typename Invoker::base::EmptyDelegate original;
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reinterpret_cast<void **>(&original)[0] = vfnptr_origentry;
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Invoker::Original( reinterpret_cast<EmptyClass*>(this), original, &original_ret, args...);
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} else {
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// TODO: Do we use context->GetOriginalRetPtr() here?
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// this is inherited from the macro versions to prevent semantic differences.
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original_ret = override_ret;
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}
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// Call all post-hooks
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prev_res = MRES_IGNORED;
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while ((iter = static_cast<IMyDelegate *>(context->GetNext()))) {
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cur_res = MRES_IGNORED;
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Invoker::Invoke(iter, ¤t_ret, args...);
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prev_res = cur_res;
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if (cur_res > status)
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status = cur_res;
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if (cur_res >= MRES_OVERRIDE)
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*reinterpret_cast<VoidSafeResult *>(context->GetOverrideRetPtr()) = current_ret;
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}
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const ResultType* result_ptr = reinterpret_cast<const ResultType *>((status >= MRES_OVERRIDE)
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? context->GetOverrideRetPtr()
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: context->GetOrigRetPtr());
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(*SH)->EndContext(context);
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return Invoker::Dereference(result_ptr);
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}
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};
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// You're probably wondering what the hell this does.
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// https://stackoverflow.com/questions/11709859/how-to-have-static-data-members-in-a-header-only-library/11711082#11711082
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// Yes, I also happen to hate C++.
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template<ISourceHook** SH, typename Interface, auto Method, typename Result, typename... Args>
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Hook<SH, Interface, Method, Result, Args...> Hook<SH, Interface, Method, Result, Args...>::Instance;
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}
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/************************************************************************/
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@ -98,8 +98,10 @@
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#ifdef _MSC_VER
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# define SH_COMP SH_COMP_MSVC
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# define SH_INLINE inline __forceinline
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#elif defined __GNUC__
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# define SH_COMP SH_COMP_GCC
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# define SH_INLINE inline __attribute__((always_inline))
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#else
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# error Unsupported compiler
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#endif
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@ -114,6 +116,7 @@
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#define SH_PTRSIZE sizeof(void*)
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#include <type_traits>
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#include "sh_memfuncinfo.h"
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#include "FastDelegate.h"
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@ -566,6 +569,434 @@ namespace SourceHook
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static const int type = 0;
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static const unsigned int flags = PassInfo::PassFlag_ByRef;
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};
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/************************************************************************/
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/* Templated hook definition */
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/************************************************************************/
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namespace metaprogramming
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{
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namespace detail
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{
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/**
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* @brief Iterate over all elements of a type pack
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*
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* @param functor A reference to the functor containing the step<index, now> template.
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*/
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template<class Functor, int Index, typename Now, typename... Rest>
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constexpr SH_INLINE void for_each_template_impl(Functor *f)
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{
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f->template step<Index, Now>();
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if constexpr (sizeof...(Rest) > 0) {
|
||||
for_each_template_impl<Functor, Index + 1, Rest...>(f);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
template<class Functor, typename First, typename... Rest>
|
||||
constexpr SH_INLINE void for_each_template(Functor* f)
|
||||
{
|
||||
detail::for_each_template_impl<Functor, 0, First, Rest...>(f);
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief Iterate over all elements of a type pack
|
||||
*
|
||||
* @param functor A reference to the functor containing the step<index, now> template.
|
||||
*/
|
||||
template<class Functor, typename First, typename... Rest>
|
||||
constexpr SH_INLINE void for_each_template_nullable(Functor* f)
|
||||
{
|
||||
for_each_template<Functor, First, Rest...>(f);
|
||||
}
|
||||
|
||||
template<class Functor>
|
||||
constexpr SH_INLINE void for_each_template_nullable(Functor* f)
|
||||
{
|
||||
// Empty varargs
|
||||
}
|
||||
|
||||
template <bool Test, class Yes = void, class No = void>
|
||||
struct if_else {
|
||||
public:
|
||||
typedef No type;
|
||||
};
|
||||
|
||||
template <class Yes, class No>
|
||||
struct if_else<true, Yes, No> {
|
||||
public:
|
||||
typedef Yes type;
|
||||
};
|
||||
}
|
||||
|
||||
namespace detail
|
||||
{
|
||||
|
||||
/**
|
||||
* @brief Build the PassInfo for a method pack.
|
||||
*
|
||||
* Iterated over using for_each_template_nullable.
|
||||
*/
|
||||
class PrototypeBuilderFunctor
|
||||
{
|
||||
public:
|
||||
constexpr PrototypeBuilderFunctor(PassInfo* p)
|
||||
: params(p) {}
|
||||
PassInfo* params;
|
||||
|
||||
template<int Index, typename Now>
|
||||
constexpr void step()
|
||||
{
|
||||
// Note: first index is always the thisptr!
|
||||
params[Index + 1] = { sizeof(Now), ::SourceHook::GetPassInfo< Now >::type, ::SourceHook::GetPassInfo< Now >::flags };
|
||||
}
|
||||
};
|
||||
|
||||
/**
|
||||
* @brief Common type for the void/non-void handling semantics.
|
||||
*
|
||||
* Basically, *(void*) is an illegal operation as it works on zero-sized
|
||||
* types. We work around this here by using these two lovely templates,
|
||||
* which both specify safe handling for void and non-void return params.
|
||||
*
|
||||
* Invoke - call the passed delegate and safely handle the return type
|
||||
* Original - call the original method and safely handle the return type
|
||||
* Dereference - dereference the return type pointer for hook return semantics
|
||||
*
|
||||
*/
|
||||
template<ISourceHook** SourceHook, typename Result, typename... Args>
|
||||
struct BaseMethodInvoker
|
||||
{
|
||||
public:
|
||||
typedef Result (EmptyClass::*EmptyDelegate)(Args...);
|
||||
};
|
||||
|
||||
template<ISourceHook** SourceHook, typename IDelegate, typename... Args>
|
||||
struct VoidMethodInvoker
|
||||
{
|
||||
public:
|
||||
typedef std::bool_constant<false> has_return;
|
||||
typedef BaseMethodInvoker<SourceHook, void, Args...> base;
|
||||
|
||||
static void Invoke(IDelegate* delegate, void* result, Args... args)
|
||||
{
|
||||
// Do not touch return type: It's void!
|
||||
delegate->Call(args...);
|
||||
}
|
||||
|
||||
static void Original(EmptyClass* self, typename base::EmptyDelegate mfp, void* result, Args... args)
|
||||
{
|
||||
// Do not touch return type: It's void!
|
||||
(self->*mfp)(args...);
|
||||
}
|
||||
|
||||
static void Dereference(const void* arg)
|
||||
{
|
||||
return;
|
||||
}
|
||||
};
|
||||
|
||||
template<ISourceHook** SourceHook, typename IDelegate, typename Result, typename... Args>
|
||||
struct ReturningMethodInvoker
|
||||
{
|
||||
public:
|
||||
typedef std::bool_constant<true> has_return;
|
||||
typedef BaseMethodInvoker<SourceHook, Result, Args...> base;
|
||||
|
||||
|
||||
static void Invoke(IDelegate* delegate, Result* result, Args... args)
|
||||
{
|
||||
*result = delegate->Call(args...);
|
||||
}
|
||||
|
||||
static void Original(EmptyClass* self, typename base::EmptyDelegate mfp, Result* result, Args... args)
|
||||
{
|
||||
*result = (self->*mfp)(args...);
|
||||
}
|
||||
|
||||
static Result Dereference(const Result* arg)
|
||||
{
|
||||
return *arg;
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
|
||||
/**
|
||||
* @brief A hook manager, used to hook instances of a specific interface.
|
||||
*
|
||||
* You must specify the SourceHook pointer, interface, method pointer,
|
||||
* and prototype in the template arguments. Any derived class of the interface
|
||||
* can be hooked using this manager.
|
||||
*/
|
||||
template<ISourceHook** SH, typename Interface, auto Method, typename Result, typename... Args>
|
||||
struct Hook
|
||||
{
|
||||
/**
|
||||
* @brief The type we expect the template arg "Method" to be.
|
||||
*/
|
||||
typedef Result (Interface::*MemberMethod)(Args...);
|
||||
typedef fastdelegate::FastDelegate<Result, Args...> Delegate;
|
||||
typedef decltype(Method) MethodType;
|
||||
|
||||
static_assert( std::is_same<MethodType, MemberMethod>::type::value, "Mismatched template parameters!" );
|
||||
|
||||
// Members
|
||||
::SourceHook::MemFuncInfo MFI;
|
||||
::SourceHook::IHookManagerInfo *HI;
|
||||
::SourceHook::ProtoInfo Proto;
|
||||
|
||||
// Singleton instance
|
||||
// Initialized below!
|
||||
static Hook Instance;
|
||||
|
||||
private:
|
||||
Hook(Hook& other) = delete;
|
||||
|
||||
/**
|
||||
* @brief Build the ProtoInfo for this hook
|
||||
*/
|
||||
constexpr Hook()
|
||||
{
|
||||
// build protoinfo
|
||||
Proto.numOfParams = sizeof...(Args);
|
||||
Proto.convention = ProtoInfo::CallConv_Unknown;
|
||||
|
||||
if constexpr (std::is_void_v<Result>) {
|
||||
Proto.retPassInfo = {0, 0, 0};
|
||||
} else {
|
||||
Proto.retPassInfo = { sizeof(Result), ::SourceHook::GetPassInfo< Result >::type, ::SourceHook::GetPassInfo< Result >::flags };
|
||||
}
|
||||
|
||||
// Iterate over the args... type pack
|
||||
auto paramsPassInfo = new PassInfo[sizeof...(Args) + 1];
|
||||
paramsPassInfo[0] = { 1, 0, 0 };
|
||||
Proto.paramsPassInfo = paramsPassInfo;
|
||||
|
||||
detail::PrototypeBuilderFunctor argsBuilder(paramsPassInfo);
|
||||
metaprogramming::for_each_template_nullable<detail::PrototypeBuilderFunctor, Args...>(&argsBuilder);
|
||||
|
||||
|
||||
// Build the backwards compatible paramsPassInfoV2 field
|
||||
Proto.retPassInfo2 = {0, 0, 0, 0};
|
||||
auto paramsPassInfo2 = new PassInfo::V2Info[sizeof...(Args) + 1];
|
||||
Proto.paramsPassInfo2 = paramsPassInfo2;
|
||||
|
||||
for (int i = 0; i /* lte to include thisptr! */ <= sizeof...(Args); ++i) {
|
||||
paramsPassInfo2[i] = { 0, 0, 0, 0 };
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
public:
|
||||
static constexpr Hook* Make()
|
||||
{
|
||||
Hook::Instance = Hook();
|
||||
|
||||
return &Hook::Instance;
|
||||
}
|
||||
|
||||
public: // Public Interface
|
||||
|
||||
/**
|
||||
* @brief Add an instance of this hook to the specified interface
|
||||
*
|
||||
* @param id the g_PLID value for the plugin creating the hook
|
||||
* @param iface the interface pointer to hook
|
||||
* @param post true when post-hooking, false when pre-hooking.
|
||||
* @param handler the handler that will be called in place of the original method
|
||||
* @param mode the hook mode - Hook_Normal will only hook this instance, while others alter the global virtual table.
|
||||
*/
|
||||
int Add(Plugin id, Interface* iface, bool post, Delegate handler, ::SourceHook::ISourceHook::AddHookMode mode = ISourceHook::AddHookMode::Hook_Normal)
|
||||
{
|
||||
using namespace ::SourceHook;
|
||||
MemFuncInfo mfi = {true, -1, 0, 0};
|
||||
GetFuncInfo(Method, mfi);
|
||||
if (mfi.thisptroffs < 0 || !mfi.isVirtual)
|
||||
return false;
|
||||
|
||||
CMyDelegateImpl* delegate = new CMyDelegateImpl(handler);
|
||||
return (*SH)->AddHook(id, mode, iface, mfi.thisptroffs, Hook::HookManPubFunc, delegate, post);
|
||||
}
|
||||
|
||||
/**
|
||||
* @brief Remove an existing hook handler from this interface
|
||||
*
|
||||
* @param id the g_PLID value for the plugin the hook was created under
|
||||
* @param iface the interface to be unhooked
|
||||
* @param post true if this was a post hook, false otherwise (pre-hook)
|
||||
* @param handler the handler that will be removed from this hook.
|
||||
*/
|
||||
int Remove(Plugin id, Interface* iface, bool post, Delegate handler)
|
||||
{
|
||||
using namespace ::SourceHook;
|
||||
MemFuncInfo mfi = {true, -1, 0, 0};
|
||||
GetFuncInfo(Method, mfi);
|
||||
|
||||
// Temporary delegate for .IsEqual() comparison.
|
||||
CMyDelegateImpl temp(handler);
|
||||
return (*SH)->RemoveHook(id, iface, mfi.thisptroffs, Hook::HookManPubFunc, &temp, post);
|
||||
}
|
||||
|
||||
protected:
|
||||
static int HookManPubFunc(bool store, ::SourceHook::IHookManagerInfo *hi)
|
||||
{
|
||||
// Build the MemberFuncInfo for the hooked method
|
||||
GetFuncInfo<MemberMethod>(static_cast<MemberMethod>(Method), Instance.MFI);
|
||||
|
||||
if ((*SH)->GetIfaceVersion() != SH_IFACE_VERSION || (*SH)->GetImplVersion() < SH_IMPL_VERSION)
|
||||
return 1;
|
||||
|
||||
if (store)
|
||||
Instance.HI = hi;
|
||||
|
||||
if (hi) {
|
||||
// Build a memberfuncinfo for our hook processor.
|
||||
MemFuncInfo our_mfi = {true, -1, 0, 0};
|
||||
GetFuncInfo(&Hook::Func, our_mfi);
|
||||
|
||||
void* us = reinterpret_cast<void **>(reinterpret_cast<char *>(&Instance) + our_mfi.vtbloffs)[our_mfi.vtblindex];
|
||||
hi->SetInfo(SH_HOOKMAN_VERSION, Instance.MFI.vtbloffs, Instance.MFI.vtblindex, &Instance.Proto, us);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
struct IMyDelegate : ::SourceHook::ISHDelegate
|
||||
{
|
||||
virtual Result Call(Args... args) = 0;
|
||||
};
|
||||
|
||||
struct CMyDelegateImpl : IMyDelegate
|
||||
{
|
||||
Delegate _delegate;
|
||||
|
||||
CMyDelegateImpl(Delegate deleg) : _delegate(deleg)
|
||||
{}
|
||||
virtual~CMyDelegateImpl() {}
|
||||
Result Call(Args... args) { return _delegate(args...); }
|
||||
void DeleteThis() { delete this; }
|
||||
bool IsEqual(ISHDelegate *pOtherDeleg) { return _delegate == static_cast<CMyDelegateImpl *>(pOtherDeleg)->_delegate; }
|
||||
|
||||
};
|
||||
|
||||
protected:
|
||||
|
||||
/**
|
||||
* @brief An object containing methods to safely handle the return type
|
||||
*
|
||||
* This allows us to safely handle zero-sized types as return values.
|
||||
*/
|
||||
typedef typename metaprogramming::if_else<
|
||||
std::is_void<Result>::value,
|
||||
detail::VoidMethodInvoker<SH, IMyDelegate, Args...>,
|
||||
detail::ReturningMethodInvoker<SH, IMyDelegate, Result, Args...>
|
||||
>::type Invoker;
|
||||
|
||||
/**
|
||||
* @brief An object containing a safely-allocatable return type
|
||||
*
|
||||
* Used when stack-allocating the return type;
|
||||
* void returns are never written to so using void* is safe.
|
||||
* when the return is not zero-sized, use the return itself.
|
||||
*/
|
||||
typedef typename metaprogramming::if_else<
|
||||
std::is_void<Result>::value,
|
||||
void*,
|
||||
Result
|
||||
>::type VoidSafeResult;
|
||||
|
||||
typedef typename ReferenceCarrier<VoidSafeResult>::type ResultType;
|
||||
|
||||
/**
|
||||
* @brief Hook handler virtual
|
||||
*/
|
||||
virtual Result Func(Args... args)
|
||||
{
|
||||
using namespace ::SourceHook;
|
||||
|
||||
void *ourvfnptr = reinterpret_cast<void *>(
|
||||
*reinterpret_cast<void ***>(reinterpret_cast<char *>(this) + Instance.MFI.vtbloffs) + Instance.MFI.vtblindex);
|
||||
void *vfnptr_origentry;
|
||||
|
||||
META_RES status = MRES_IGNORED;
|
||||
META_RES prev_res;
|
||||
META_RES cur_res;
|
||||
|
||||
ResultType original_ret;
|
||||
ResultType override_ret;
|
||||
ResultType current_ret;
|
||||
|
||||
IMyDelegate *iter;
|
||||
IHookContext *context = (*SH)->SetupHookLoop(
|
||||
Instance.HI,
|
||||
ourvfnptr,
|
||||
reinterpret_cast<void *>(this),
|
||||
&vfnptr_origentry,
|
||||
&status,
|
||||
&prev_res,
|
||||
&cur_res,
|
||||
&original_ret,
|
||||
&override_ret);
|
||||
|
||||
// Call all pre-hooks
|
||||
prev_res = MRES_IGNORED;
|
||||
while ((iter = static_cast<IMyDelegate *>(context->GetNext()))) {
|
||||
cur_res = MRES_IGNORED;
|
||||
Invoker::Invoke(iter, ¤t_ret, args...);
|
||||
prev_res = cur_res;
|
||||
|
||||
if (cur_res > status)
|
||||
status = cur_res;
|
||||
|
||||
if (cur_res >= MRES_OVERRIDE)
|
||||
*reinterpret_cast<ResultType *>(context->GetOverrideRetPtr()) = current_ret;
|
||||
}
|
||||
|
||||
// Call original method
|
||||
if (status != MRES_SUPERCEDE && context->ShouldCallOrig()) {
|
||||
typename Invoker::base::EmptyDelegate original;
|
||||
reinterpret_cast<void **>(&original)[0] = vfnptr_origentry;
|
||||
Invoker::Original( reinterpret_cast<EmptyClass*>(this), original, &original_ret, args...);
|
||||
} else {
|
||||
// TODO: Do we use context->GetOriginalRetPtr() here?
|
||||
// this is inherited from the macro versions to prevent semantic differences.
|
||||
original_ret = override_ret;
|
||||
}
|
||||
|
||||
// Call all post-hooks
|
||||
prev_res = MRES_IGNORED;
|
||||
while ((iter = static_cast<IMyDelegate *>(context->GetNext()))) {
|
||||
cur_res = MRES_IGNORED;
|
||||
Invoker::Invoke(iter, ¤t_ret, args...);
|
||||
prev_res = cur_res;
|
||||
|
||||
if (cur_res > status)
|
||||
status = cur_res;
|
||||
|
||||
if (cur_res >= MRES_OVERRIDE)
|
||||
*reinterpret_cast<VoidSafeResult *>(context->GetOverrideRetPtr()) = current_ret;
|
||||
}
|
||||
|
||||
const ResultType* result_ptr = reinterpret_cast<const ResultType *>((status >= MRES_OVERRIDE)
|
||||
? context->GetOverrideRetPtr()
|
||||
: context->GetOrigRetPtr());
|
||||
|
||||
(*SH)->EndContext(context);
|
||||
|
||||
return Invoker::Dereference(result_ptr);
|
||||
}
|
||||
|
||||
};
|
||||
|
||||
// You're probably wondering what the hell this does.
|
||||
// https://stackoverflow.com/questions/11709859/how-to-have-static-data-members-in-a-header-only-library/11711082#11711082
|
||||
// Yes, I also happen to hate C++.
|
||||
template<ISourceHook** SH, typename Interface, auto Method, typename Result, typename... Args>
|
||||
Hook<SH, Interface, Method, Result, Args...> Hook<SH, Interface, Method, Result, Args...>::Instance;
|
||||
|
||||
}
|
||||
|
||||
/************************************************************************/
|
||||
|
||||
Loading…
Reference in New Issue
Block a user