feat: add il2cppString transformation utils

module/src/main/cpp/CMakeLists.txt

@@ -28,6 +28,7 @@ set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${LINKER_FLAGS}")
 set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} ${LINKER_FLAGS}")
 
 include_directories(xdl/include)
+include_directories(utf8-cpp/source)
 
 aux_source_directory(xdl xdl-src)
 

module/src/main/cpp/string_utils.cpp

@@ -0,0 +1,31 @@
+//
+// Created by StarHeartHunt on 2023/4/3.
+//
+
+#include "string_utils.h"
+
+std::string Utf16ToUtf8(const Il2CppChar *utf16String, int maximumSize) {
+    const Il2CppChar *ptr = utf16String;
+    size_t length = 0;
+    while (*ptr) {
+        ptr++;
+        length++;
+        if (maximumSize != -1 && length == maximumSize)
+            break;
+    }
+
+    std::string utf8String;
+    utf8String.reserve(length);
+    utf8::unchecked::utf16to8(utf16String, ptr, std::back_inserter(utf8String));
+
+    return utf8String;
+}
+
+std::string Utf16ToUtf8(const Il2CppChar *utf16String) {
+    return Utf16ToUtf8(utf16String, -1);
+}
+
+std::string Il2CppStringToStdString(Il2CppString *str) {
+    auto chars = il2cpp_string_chars(str);
+    return Utf16ToUtf8(chars);
+}

module/src/main/cpp/string_utils.h

@@ -0,0 +1,14 @@
+//
+// Created by StarHeartHunt on 2023/4/3.
+//
+
+#ifndef ZYGISK_IL2CPPDUMPER_STRING_UTILS_H
+#define ZYGISK_IL2CPPDUMPER_STRING_UTILS_H
+
+#include "utf8.h"
+
+std::string Utf16ToUtf8(const Il2CppChar *utf16String, int maximumSize);
+std::string Utf16ToUtf8(const Il2CppChar *utf16String);
+std::string Il2CppStringToStdString(Il2CppString *str);
+
+#endif //ZYGISK_IL2CPPDUMPER_STRING_UTILS_H

module/src/main/cpp/utf8-cpp/source/utf8.h

@@ -0,0 +1,34 @@
+// Copyright 2006 Nemanja Trifunovic
+
+/*
+Permission is hereby granted, free of charge, to any person or organization
+obtaining a copy of the software and accompanying documentation covered by
+this license (the "Software") to use, reproduce, display, distribute,
+execute, and transmit the Software, and to prepare derivative works of the
+Software, and to permit third-parties to whom the Software is furnished to
+do so, all subject to the following:
+
+The copyright notices in the Software and this entire statement, including
+the above license grant, this restriction and the following disclaimer,
+must be included in all copies of the Software, in whole or in part, and
+all derivative works of the Software, unless such copies or derivative
+works are solely in the form of machine-executable object code generated by
+a source language processor.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
+SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
+FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+*/
+
+
+#ifndef UTF8_FOR_CPP_2675DCD0_9480_4c0c_B92A_CC14C027B731
+#define UTF8_FOR_CPP_2675DCD0_9480_4c0c_B92A_CC14C027B731
+
+#include "utf8/checked.h"
+#include "utf8/unchecked.h"
+
+#endif // header guard