Merge pull request #151 from shad0wshayd3-TES5/dev-replace-func

refactor: Relocation::replace_func
powerof3 · Nov 17, 2024 · cc3edf1 · cc3edf1
2 parents 105df57 + 74e5bce
commit cc3edf1
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Showing 2 changed files with 31 additions and 40 deletions.
diff --git a/include/REL/Relocation.h b/include/REL/Relocation.h
@@ -282,6 +282,37 @@ namespace REL
 			return stl::unrestricted_cast<value_type>(_impl);
 		}
 
+		template <std::ptrdiff_t O = 0>
+		void replace_func(const std::size_t a_count, const std::uintptr_t a_dst) requires(std::same_as<value_type, std::uintptr_t>)
+		{
+#pragma pack(push, 1)
+			struct Assembly
+			{
+				std::uint8_t  jmp;
+				std::uint8_t  modrm;
+				std::int32_t  disp;
+				std::uint64_t addr;
+			};
+			static_assert(sizeof(Assembly) == 0xE);
+#pragma pack(pop)
+
+			Assembly assembly{
+				.jmp = static_cast<std::uint8_t>(0xFF),
+				.modrm = static_cast<std::uint8_t>(0x25),
+				.disp = static_cast<std::int32_t>(0),
+				.addr = static_cast<std::uint64_t>(a_dst),
+			};
+
+			safe_fill(address() + O, INT3, a_count);
+			safe_write(address() + O, &assembly, sizeof(assembly));
+		}
+
+		template <std::ptrdiff_t O = 0, class F>
+		void replace_func(const std::size_t a_count, const F a_dst) requires(std::same_as<value_type, std::uintptr_t>)
+		{
+			replace_func<O>(a_count, stl::unrestricted_cast<std::uintptr_t>(a_dst));
+		}
+
 		template <std::integral U>
 		void write(const U& a_data) requires(std::same_as<value_type, std::uintptr_t>)
 		{
@@ -323,16 +354,6 @@ namespace REL
 			safe_fill(address(), a_value, a_count);
 		}
 
-#ifdef SKSE_SUPPORT_XBYAK
-		void write_func(const std::size_t a_count, const std::uintptr_t a_dst) requires(std::same_as<value_type, std::uintptr_t>);
-
-		template <class F>
-		void write_func(const std::size_t a_count, const F a_dst) requires(std::same_as<value_type, std::uintptr_t>)
-		{
-			write_func(a_count, stl::unrestricted_cast<std::uintptr_t>(a_dst));
-		}
-#endif
-
 		template <class U = value_type>
 		std::uintptr_t write_vfunc(const std::size_t a_idx, const std::uintptr_t a_newFunc) requires(std::same_as<U, std::uintptr_t>)
 		{

diff --git a/src/REL/Relocation.cpp b/src/REL/Relocation.cpp
@@ -32,33 +32,3 @@ namespace REL
 		assert(success);
 	}
 }
-
-#ifdef SKSE_SUPPORT_XBYAK
-#	include <xbyak/xbyak.h>
-
-namespace REL
-{
-	struct write_func_impl : Xbyak::CodeGenerator
-	{
-		write_func_impl(std::uintptr_t a_dst)
-		{
-			Xbyak::Label dst;
-			jmp(ptr[rip + dst]);
-			L(dst);
-			dq(a_dst);
-		}
-	};
-
-	template <class T>
-	void Relocation<T>::write_func(const std::size_t a_count, const std::uintptr_t a_dst) requires(std::same_as<value_type, std::uintptr_t>)
-	{
-		safe_fill(address(), INT3, a_count);
-		auto patch = write_func_impl{ a_dst };
-		patch.ready();
-		assert(patch.getSize() <= a_count);
-		safe_write(address(), std::span{ patch.getCode<const std::byte*>(), patch.getSize() });
-	}
-
-	template void Relocation<std::uintptr_t>::write_func(const std::size_t, const std::uintptr_t);
-}
-#endif