MCW10String.cpp

// Class wich emulates MCW10 32-byte strings
// Super basic
class String
{
	union {
		char charBuffer[16];
		char* charPtr;
	};

	size_t Length = 0;
	size_t Capacity = 0;

public:
	String(std::string str)
	{
		unsigned char* bytePtr = reinterpret_cast<unsigned char*>(&str);
		bytePtr += 8;
		memcpy(this, (void*)bytePtr, 32);

		// char buffer is too long so store it as a pointer
		if (Capacity > 15)
		{
			char* oldptr = charPtr;
			charPtr = new char[Capacity + 1];
			ZeroMemory(charPtr, Capacity + 1);

			memcpy(charPtr, oldptr, Length);
		}
	}

	~String()
	{
		if (Capacity > 15)
			delete charPtr;
	}

	// Hopefully bug free; copy assignment for string literal/ptr
	String& operator=(const char* ptr) {
		char curChar = *ptr;
		int iter = 0;

		// Iterate over the char ptr until a nullchar is found or the max length is exceeded
		while (curChar != '\0' && iter++ < 0x1000)
		{
			curChar = *(ptr + iter);
		}

		Length = iter;

		// Round capacity up to the nearst 8 bytes
		// Could use sizeOf(void*) instead of hard-coding the size
		Capacity = iter + 8 - (iter % 8);

		// char buffer is too long so store it as a ptr
		if (Capacity > 15)
		{
			charPtr = new char[Capacity + 1];
			ZeroMemory(charPtr, Capacity + 1);

			memcpy(charPtr, ptr, iter);
		}
		else
		{
			ZeroMemory(charBuffer, 16);
			memcpy(charPtr, ptr, iter);
		}

		return *this;
	}

	// Probably only works with MSVC
	String& operator=(std::string str) {
		unsigned char* strPtr = reinterpret_cast<unsigned char*>(&str);
		strPtr += 8;

		memcpy(this, (void*)strPtr, 32);

		// char buffer stored as a ptr
		if (Capacity > 15)
		{
			char* oldptr = charPtr;
			charPtr = new char[Capacity + 1];
			ZeroMemory(charPtr, Capacity + 1);

			memcpy(charPtr, oldptr, Length);
		}

		return *this;
	}

	// For compatibility with std::string.size()
	size_t size()
	{
		return Length;
	}

	size_t length()
	{
		return Length;
	}

	size_t capacity()
	{
		return Capacity;
	}

	std::string ToString()
	{
		if (Capacity > 15)
		{
			return std::string(charPtr);
		}

		return std::string(charBuffer);
	}
};