RLP prototype implementation.

11 years ago · 85aaddc694
2 changed files with 224 additions and 0 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -0,0 +1,26 @@
+project(ethereum)
+cmake_minimum_required(VERSION 2.8)
+
+# Initialize CXXFLAGS.
+set(CMAKE_CXX_FLAGS                "-Wall -std=c++11")
+set(CMAKE_CXX_FLAGS_DEBUG          "-O0 -g")
+set(CMAKE_CXX_FLAGS_MINSIZEREL     "-Os -DNDEBUG")
+set(CMAKE_CXX_FLAGS_RELEASE        "-O4 -DNDEBUG")
+set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-O2 -g")
+
+# Compiler-specific C++11 activation.
+if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU")
+	execute_process(
+		COMMAND ${CMAKE_CXX_COMPILER} -dumpversion OUTPUT_VARIABLE GCC_VERSION)
+	if (NOT (GCC_VERSION VERSION_GREATER 4.7 OR GCC_VERSION VERSION_EQUAL 4.7))
+		message(FATAL_ERROR "${PROJECT_NAME} requires g++ 4.7 or greater.")
+	endif ()
+elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
+	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
+else ()
+	message(FATAL_ERROR "Your C++ compiler does not support C++11.")
+endif ()
+
+
+aux_source_directory(. SRC_LIST)
+add_executable(${PROJECT_NAME} ${SRC_LIST})
--- a/main.cpp
+++ b/main.cpp
@ -0,0 +1,198 @@
+#include <iostream>
+#include <cstdint>
+#include <cassert>
+#include <type_traits>
+#include <vector>
+#include <string>
+#include <memory>
+
+typedef uint8_t byte;
+
+template <class _T>
+class foreign
+{
+public:
+	typedef _T value_type;
+	typedef _T element_type;
+
+	foreign(): m_data(nullptr), m_count(0) {}
+	foreign(std::vector<typename std::remove_const<_T>::type>* _data): m_data(_data->data()), m_count(_data->size()) {}
+	foreign(_T* _data, unsigned _count): m_data(_data), m_count(_count) {}
+	foreign(std::shared_ptr<std::vector<typename std::remove_const<_T>::type> > const& _data): m_data(_data->data()), m_count(_data->size()) {}
+
+	explicit operator bool() const { return m_data && m_count; }
+
+	std::vector<_T> toVector() const { return std::vector<_T>(m_data, m_data + m_count); }
+	std::string toString() const { return std::string((char const*)m_data, ((char const*)m_data) + m_count); }
+	template <class _T2> operator foreign<_T2>() const { assert(m_count * sizeof(_T) / sizeof(_T2) * sizeof(_T2) / sizeof(_T) == m_count); return foreign<_T2>((_T2*)m_data, m_count * sizeof(_T) / sizeof(_T2)); }
+
+	_T* data() const { return m_data; }
+	unsigned count() const { return m_count; }
+	unsigned size() const { return m_count; }
+	foreign<_T> next() const { return foreign<_T>(m_data + m_count, m_count); }
+	foreign<_T> cropped(unsigned _begin, int _count = -1) const { if (m_data && _begin + std::max(0, _count) <= m_count) return foreign<_T>(m_data + _begin, _count < 0 ? m_count - _begin : _count); else return foreign<_T>(); }
+	void retarget(_T const* _d, size_t _s) { m_data = _d; m_count = _s; }
+	void retarget(std::vector<_T> const& _t) { m_data = _t.data(); m_count = _t.size(); }
+
+	_T* begin() { return m_data; }
+	_T* end() { return m_data + m_count; }
+	_T const* begin() const { return m_data; }
+	_T const* end() const { return m_data + m_count; }
+
+	_T& operator[](unsigned _i) { assert(m_data); assert(_i < m_count); return m_data[_i]; }
+	_T const& operator[](unsigned _i) const { assert(m_data); assert(_i < m_count); return m_data[_i]; }
+
+	void reset() { m_data = nullptr; m_count = 0; }
+
+private:
+	_T* m_data;
+	unsigned m_count;
+};
+
+typedef foreign<byte> Bytes;
+class RLP;
+typedef std::vector<RLP> RLPs;
+
+class RLP
+{
+public:
+	RLP() {}
+	RLP(Bytes _d): m_data(_d) {}
+
+	explicit operator bool() const { return !isNull(); }
+	bool isNull() const { return m_data.size() == 0; }
+	bool isString() const { assert(!isNull()); return m_data[0] >= 0x40 && m_data[0] < 0x80; }
+	bool isList() const { assert(!isNull()); return m_data[0] >= 0x80 && m_data[0] < 0xc0; }
+	bool isInt() const { assert(!isNull()); return m_data[0] < 0x40; }
+	bool isSmallString() const { assert(!isNull()); return m_data[0] >= 0x40 && m_data[0] < 0x78; }
+	bool isSmallList() const { assert(!isNull()); return m_data[0] >= 0x80 && m_data[0] < 0xb8; }
+	bool isSmallInt() const { assert(!isNull()); return m_data[0] < 0x20; }
+	int intSize() const { return (!isInt() || isSmallInt()) ? 0 : m_data[0] - 0x1f; }
+
+	uint64_t size() const
+	{
+		if (isInt())
+			return 1 + intSize();
+		if (isString())
+			return payload().data() - m_data.data() + items();
+		if (isList())
+		{
+			Bytes d = payload();
+			uint64_t c = items();
+			for (uint64_t i = 0; i < c; ++i, d = d.cropped(RLP(d).size())) {}
+			return d.data() - m_data.data();
+		}
+		return 0;
+	}
+
+	std::string toString() const
+	{
+		if (!isString())
+			return std::string();
+		return payload().cropped(0, items()).toString();
+	}
+
+	uint64_t toInt(uint64_t _def = 0) const
+	{
+		if (!isInt())
+			return _def;
+		if (isSmallInt())
+			return m_data[0];
+		uint64_t ret = 0;
+		for (int i = 0; i < intSize(); ++i)
+			ret = (ret << 8) | m_data[i + 1];
+		return ret;
+	}
+
+	RLPs toList() const
+	{
+		RLPs ret;
+		if (!isList())
+			return ret;
+		uint64_t c = items();
+		Bytes d = payload();
+		for (uint64_t i = 0; i < c; ++i, d = d.cropped(RLP(d).size()))
+			ret.push_back(RLP(d));
+		return ret;
+	}
+
+/*	static uint64_t intLength(Bytes _b)
+	{
+		return _b[0] < 253 ? 1 : _b[0] == 253 ? 3 : _b[0] == 254 ? 5 : 9;
+	}
+
+	static uint64_t toInt(Bytes _b)
+	{
+		return _b[0] < 253 ?
+					_b[0] :
+				_b[0] == 253 ?
+					(((uint64_t)_b[1]) << 8) |
+					_b[2] :
+				_b[0] == 254 ?
+					(((uint64_t)_b[1]) << 24) |
+					(((uint64_t)_b[2]) << 16) |
+					(((uint64_t)_b[3]) << 8) |
+					_b[4]
+				: (
+					(((uint64_t)_b[1]) << 56) |
+					(((uint64_t)_b[2]) << 48) |
+					(((uint64_t)_b[3]) << 40) |
+					(((uint64_t)_b[4]) << 32) |
+					(((uint64_t)_b[5]) << 24) |
+					(((uint64_t)_b[6]) << 16) |
+					(((uint64_t)_b[7]) << 8) |
+					_b[8]
+				);
+	}*/
+
+private:
+	uint64_t items() const
+	{
+		assert(isString() || isList());
+		auto n = (m_data[0] & 0x3f);
+		if (n < 0x38)
+			return n;
+		uint64_t ret = 0;
+		for (int i = 0; i < n; ++i)
+			ret = (ret << 8) | m_data[i + 1];
+		return ret;
+	}
+
+	Bytes payload() const
+	{
+		assert(isString() || isList());
+		auto n = (m_data[0] & 0x3f);
+		return m_data.cropped(1 + (n < 0x38 ? 0 : n));
+	}
+
+	Bytes m_data;
+};
+
+std::ostream& operator<<(std::ostream& _out, RLP _d)
+{
+	if (_d.isNull())
+		_out << "null";
+	else if (_d.isInt())
+		_out << _d.toInt();
+	else if (_d.isString())
+		_out << "\"" << _d.toString() << "\"";
+	else if (_d.isList())
+	{
+		_out << "[";
+		int j = 0;
+		for (auto i: _d.toList())
+			_out << (j++ ? ", " : " ") << i;
+		_out << "]";
+	}
+
+	return _out;
+}
+
+using namespace std;
+
+int main()
+{
+	cout << "Hello World!" << endl;
+	return 0;
+}
+