added call_method

include/omath/rev_eng/internal_rev_object.hpp

@@ -3,11 +3,39 @@
 //
 
 #pragma once
+#include <algorithm>
+#include <cassert>
 #include <cstddef>
 #include <cstdint>
+#include <string_view>
+
+#ifdef _WIN32
+#include "omath/utility/pe_pattern_scan.hpp"
+#include <windows.h>
+#elif defined(__APPLE__)
+#include "omath/utility/macho_pattern_scan.hpp"
+#include <mach-o/dyld.h>
+#else
+#include "omath/utility/elf_pattern_scan.hpp"
+#include <link.h>
+#endif
 
 namespace omath::rev_eng
 {
+    template<std::size_t N>
+    struct FixedString
+    {
+        char data[N]{};
+        constexpr FixedString(const char (&str)[N])
+        {
+            std::copy_n(str, N, data);
+        }
+        constexpr operator std::string_view() const
+        {
+            return {data, N - 1};
+        }
+    };
+
     class InternalReverseEngineeredObject
     {
     protected:
@@ -23,26 +51,122 @@ namespace omath::rev_eng
             return *reinterpret_cast<Type*>(reinterpret_cast<std::uintptr_t>(this) + offset);
         }
 
+        template<class ReturnType>
+        ReturnType call_method(const void* ptr, auto... arg_list)
+        {
+#ifdef _MSC_VER
+            using MethodType = ReturnType(__thiscall*)(void*, decltype(arg_list)...);
+#else
+            using MethodType = ReturnType (*)(void*, decltype(arg_list)...);
+#endif
+            return reinterpret_cast<MethodType>(const_cast<void*>(ptr))(this, arg_list...);
+        }
+        template<class ReturnType>
+        ReturnType call_method(const void* ptr, auto... arg_list) const
+        {
+#ifdef _MSC_VER
+            using MethodType = ReturnType(__thiscall*)(const void*, decltype(arg_list)...);
+#else
+            using MethodType = ReturnType (*)(const void*, decltype(arg_list)...);
+#endif
+            return reinterpret_cast<MethodType>(const_cast<void*>(ptr))(this, arg_list...);
+        }
+
+        template<FixedString module_name, FixedString pattern, class ReturnType>
+        ReturnType call_method(auto... arg_list)
+        {
+            static const auto address = []() -> const void*
+            {
+                const auto* base = get_module_base(module_name);
+                assert(base && "Failed to find module");
+
+#ifdef _WIN32
+                auto result = PePatternScanner::scan_for_pattern_in_loaded_module(base, pattern);
+#elif defined(__APPLE__)
+                auto result = MachOPatternScanner::scan_for_pattern_in_loaded_module(base, pattern);
+#else
+                auto result = ElfPatternScanner::scan_for_pattern_in_loaded_module(base, pattern);
+#endif
+                assert(result.has_value() && "Pattern scan failed");
+                return reinterpret_cast<const void*>(*result);
+            }();
+
+            return call_method<ReturnType>(address, arg_list...);
+        }
+
+        template<FixedString module_name, FixedString pattern, class ReturnType>
+        ReturnType call_method(auto... arg_list) const
+        {
+            static const auto address = []() -> const void*
+            {
+                const auto* base = get_module_base(module_name);
+                assert(base && "Failed to find module");
+
+#ifdef _WIN32
+                auto result = PePatternScanner::scan_for_pattern_in_loaded_module(base, pattern);
+#elif defined(__APPLE__)
+                auto result = MachOPatternScanner::scan_for_pattern_in_loaded_module(base, pattern);
+#else
+                auto result = ElfPatternScanner::scan_for_pattern_in_loaded_module(base, pattern);
+#endif
+                assert(result.has_value() && "Pattern scan failed");
+                return reinterpret_cast<const void*>(*result);
+            }();
+
+            return call_method<ReturnType>(address, arg_list...);
+        }
+
         template<std::size_t id, class ReturnType>
         ReturnType call_virtual_method(auto... arg_list)
         {
-#ifdef _MSC_VER
-            using VirtualMethodType = ReturnType(__thiscall*)(void*, decltype(arg_list)...);
-#else
-            using VirtualMethodType = ReturnType (*)(void*, decltype(arg_list)...);
-#endif
-            return (*reinterpret_cast<VirtualMethodType**>(this))[id](this, arg_list...);
+            const auto vtable = *reinterpret_cast<void***>(this);
+            return call_method<ReturnType>(vtable[id], arg_list...);
         }
         template<std::size_t id, class ReturnType>
         ReturnType call_virtual_method(auto... arg_list) const
         {
-#ifdef _MSC_VER
-            using VirtualMethodType = ReturnType(__thiscall*)(void*, decltype(arg_list)...);
+            const auto vtable = *reinterpret_cast<void* const* const*>(this);
+            return call_method<ReturnType>(vtable[id], arg_list...);
+        }
+
+    private:
+        static const void* get_module_base(const std::string_view module_name)
+        {
+#ifdef _WIN32
+            return static_cast<const void*>(GetModuleHandleA(module_name.data()));
+#elif defined(__APPLE__)
+            // On macOS, iterate loaded images to find the module by name
+            const auto count = _dyld_image_count();
+            for (std::uint32_t i = 0; i < count; ++i)
+            {
+                const auto* name = _dyld_get_image_name(i);
+                if (name && std::string_view{name}.find(module_name) != std::string_view::npos)
+                    return static_cast<const void*>(_dyld_get_image_header(i));
+            }
+            return nullptr;
 #else
-            using VirtualMethodType = ReturnType (*)(void*, decltype(arg_list)...);
+            // On Linux, use dl_iterate_phdr to find loaded module by name
+            struct CallbackData
+            {
+                std::string_view name;
+                const void* base;
+            } cb_data{module_name, nullptr};
+
+            dl_iterate_phdr(
+                    [](dl_phdr_info* info, std::size_t, void* data) -> int
+                    {
+                        auto* cb = static_cast<CallbackData*>(data);
+                        if (info->dlpi_name
+                            && std::string_view{info->dlpi_name}.find(cb->name) != std::string_view::npos)
+                        {
+                            cb->base = reinterpret_cast<const void*>(info->dlpi_addr);
+                            return 1;
+                        }
+                        return 0;
+                    },
+                    &cb_data);
+            return cb_data.base;
 #endif
-            return (*static_cast<VirtualMethodType**>((void*)(this)))[id](
-                    const_cast<void*>(static_cast<const void*>(this)), arg_list...);
         }
     };
 } // namespace omath::rev_eng