Add initial project files (excluding ignored content)

external/safetyhook/README.md

@@ -0,0 +1,71 @@
+# SafetyHook
+
+SafetyHook is a **C++23** procedure hooking library for Windows x86 and x86_64 systems. It aims to make runtime procedure hooking as safe as possible while maintaining simplicity of its implementation. To that end it currently does:
+
+* Stops all other threads when creating or deleting hooks
+* Fixes the IP of threads that may be affected by the creation or deletion of hooks
+* Fixes IP relative displacements of relocated instructions (eg. `lea rax, [rip + 0x1234]`)
+* Fixes relative offsets of relocated instructions (eg. `jmp 0x1234`)
+* Widens short branches into near branches
+* Handles short branches that land within the trampoline
+* Uses a modern disassembler engine that supports the latest instructions
+* Has a carefully designed API that is hard to misuse
+
+## Installation
+
+SafetyHook can be added via CMake's `FetchContent`, git submodules, or copied directly into your project using the amalgamated builds. SafetyHook requires [Zydis](https://github.com/zyantific/zydis) to function.
+
+### Amalgamated builds
+
+This is the easiest way to use safety hook. You can find amalgamated builds on the releases page. Simply download the ZIP file containing [Zydis](https://github.com/zyantific/zydis) (or without [Zydis](https://github.com/zyantific/zydis) if you already have it in your project) and copy the files into your project.
+
+You may need to define `ZYDIS_STATIC_BUILD` if you're using the build with [Zydis](https://github.com/zyantific/zydis) included.
+
+### CMake FetchContent
+
+```CMake
+include(FetchContent)
+
+# Safetyhook
+FetchContent_Declare(
+    safetyhook
+    GIT_REPOSITORY "https://github.com/cursey/safetyhook.git"
+    GIT_TAG "origin/main"
+)
+FetchContent_MakeAvailable(safetyhook)
+```
+
+If you want SafetyHook to fetch [Zydis](https://github.com/zyantific/zydis) you must enable the CMake option `-DSAFETYHOOK_FETCH_ZYDIS=ON`.
+
+## Usage
+
+```C++
+#include <iostream>
+
+#include <safetyhook.hpp>
+
+__declspec(noinline) int add(int x, int y) {
+    return x + y;
+}
+
+SafetyHookInline g_add_hook{};
+
+int hook_add(int x, int y) {
+    return g_add_hook.call<int>(x * 2, y * 2);
+}
+
+int main() {
+    std::cout << "unhooked add(2, 3) = " << add(2, 3) << "\n";
+
+    // Create a hook on add (This uses SafetyHook's easy API).
+    g_add_hook = safetyhook::create_inline(reinterpret_cast<void*>(add), reinterpret_cast<void*>(hook_add));
+
+    std::cout << "hooked add(3, 4) = " << add(3, 4) << "\n";
+
+    g_add_hook = {};
+
+    std::cout << "unhooked add(5, 6) = " << add(5, 6) << "\n";
+
+    return 0;
+}
+```