solidity/libdevcore/CommonData.h
2019-10-30 17:31:33 +01:00

442 lines
14 KiB
C++

/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file CommonData.h
* @author Gav Wood <i@gavwood.com>
* @date 2014
*
* Shared algorithms and data types.
*/
#pragma once
#include <iterator>
#include <libdevcore/Common.h>
#include <vector>
#include <type_traits>
#include <cstring>
#include <optional>
#include <string>
#include <set>
#include <functional>
#include <utility>
/// Operators need to stay in the global namespace.
/// Concatenate the contents of a container onto a vector
template <class T, class U> std::vector<T>& operator+=(std::vector<T>& _a, U const& _b)
{
for (auto const& i: _b)
_a.push_back(i);
return _a;
}
/// Concatenate the contents of a container onto a vector, move variant.
template <class T, class U> std::vector<T>& operator+=(std::vector<T>& _a, U&& _b)
{
std::move(_b.begin(), _b.end(), std::back_inserter(_a));
return _a;
}
/// Concatenate the contents of a container onto a multiset
template <class U, class... T> std::multiset<T...>& operator+=(std::multiset<T...>& _a, U const& _b)
{
_a.insert(_b.begin(), _b.end());
return _a;
}
/// Concatenate the contents of a container onto a multiset, move variant.
template <class U, class... T> std::multiset<T...>& operator+=(std::multiset<T...>& _a, U&& _b)
{
for (auto&& x: _b)
_a.insert(std::move(x));
return _a;
}
/// Concatenate the contents of a container onto a set
template <class U, class... T> std::set<T...>& operator+=(std::set<T...>& _a, U const& _b)
{
_a.insert(_b.begin(), _b.end());
return _a;
}
/// Concatenate the contents of a container onto a set, move variant.
template <class U, class... T> std::set<T...>& operator+=(std::set<T...>& _a, U&& _b)
{
for (auto&& x: _b)
_a.insert(std::move(x));
return _a;
}
/// Concatenate two vectors of elements.
template <class T>
inline std::vector<T> operator+(std::vector<T> const& _a, std::vector<T> const& _b)
{
std::vector<T> ret(_a);
ret += _b;
return ret;
}
/// Concatenate two vectors of elements, moving them.
template <class T>
inline std::vector<T> operator+(std::vector<T>&& _a, std::vector<T>&& _b)
{
std::vector<T> ret(std::move(_a));
if (&_a == &_b)
ret += ret;
else
ret += std::move(_b);
return ret;
}
/// Concatenate something to a sets of elements.
template <class T, class U>
inline std::set<T> operator+(std::set<T> const& _a, U&& _b)
{
std::set<T> ret(_a);
ret += std::forward<U>(_b);
return ret;
}
/// Concatenate something to a sets of elements, move variant.
template <class T, class U>
inline std::set<T> operator+(std::set<T>&& _a, U&& _b)
{
std::set<T> ret(std::move(_a));
ret += std::forward<U>(_b);
return ret;
}
/// Remove one set from another one.
template <class... T>
inline std::set<T...>& operator-=(std::set<T...>& _a, std::set<T...> const& _b)
{
for (auto const& x: _b)
_a.erase(x);
return _a;
}
template <class... T>
inline std::set<T...> operator-(std::set<T...> const& _a, std::set<T...> const& _b)
{
auto result = _a;
result -= _b;
return result;
}
namespace dev
{
template <class T, class U>
T convertContainer(U const& _from)
{
return T{_from.cbegin(), _from.cend()};
}
template <class T, class U>
T convertContainer(U&& _from)
{
return T{
std::make_move_iterator(_from.begin()),
std::make_move_iterator(_from.end())
};
}
// String conversion functions, mainly to/from hex/nibble/byte representations.
enum class WhenError
{
DontThrow = 0,
Throw = 1,
};
enum class HexPrefix
{
DontAdd = 0,
Add = 1,
};
enum class HexCase
{
Lower = 0,
Upper = 1,
Mixed = 2,
};
/// Convert a series of bytes to the corresponding string of hex duplets.
/// @param _w specifies the width of the first of the elements. Defaults to two - enough to represent a byte.
/// @example toHex("A\x69") == "4169"
std::string toHex(bytes const& _data, HexPrefix _prefix = HexPrefix::DontAdd, HexCase _case = HexCase::Lower);
/// Converts a (printable) ASCII hex character into the corresponding integer value.
/// @example fromHex('A') == 10 && fromHex('f') == 15 && fromHex('5') == 5
int fromHex(char _i, WhenError _throw);
/// Converts a (printable) ASCII hex string into the corresponding byte stream.
/// @example fromHex("41626261") == asBytes("Abba")
/// If _throw = ThrowType::DontThrow, it replaces bad hex characters with 0's, otherwise it will throw an exception.
bytes fromHex(std::string const& _s, WhenError _throw = WhenError::DontThrow);
/// Converts byte array to a string containing the same (binary) data. Unless
/// the byte array happens to contain ASCII data, this won't be printable.
inline std::string asString(bytes const& _b)
{
return std::string((char const*)_b.data(), (char const*)(_b.data() + _b.size()));
}
/// Converts byte array ref to a string containing the same (binary) data. Unless
/// the byte array happens to contain ASCII data, this won't be printable.
inline std::string asString(bytesConstRef _b)
{
return std::string((char const*)_b.data(), (char const*)(_b.data() + _b.size()));
}
/// Converts a string to a byte array containing the string's (byte) data.
inline bytes asBytes(std::string const& _b)
{
return bytes((uint8_t const*)_b.data(), (uint8_t const*)(_b.data() + _b.size()));
}
// Big-endian to/from host endian conversion functions.
/// Converts a templated integer value to the big-endian byte-stream represented on a templated collection.
/// The size of the collection object will be unchanged. If it is too small, it will not represent the
/// value properly, if too big then the additional elements will be zeroed out.
/// @a Out will typically be either std::string or bytes.
/// @a T will typically by unsigned, u160, u256 or bigint.
template <class T, class Out>
inline void toBigEndian(T _val, Out& o_out)
{
static_assert(std::is_same<bigint, T>::value || !std::numeric_limits<T>::is_signed, "only unsigned types or bigint supported"); //bigint does not carry sign bit on shift
for (auto i = o_out.size(); i != 0; _val >>= 8, i--)
{
T v = _val & (T)0xff;
o_out[i - 1] = (typename Out::value_type)(uint8_t)v;
}
}
/// Converts a big-endian byte-stream represented on a templated collection to a templated integer value.
/// @a _In will typically be either std::string or bytes.
/// @a T will typically by unsigned, u160, u256 or bigint.
template <class T, class _In>
inline T fromBigEndian(_In const& _bytes)
{
T ret = (T)0;
for (auto i: _bytes)
ret = (T)((ret << 8) | (uint8_t)(typename std::make_unsigned<typename _In::value_type>::type)i);
return ret;
}
inline bytes toBigEndian(u256 _val) { bytes ret(32); toBigEndian(_val, ret); return ret; }
inline bytes toBigEndian(u160 _val) { bytes ret(20); toBigEndian(_val, ret); return ret; }
/// Convenience function for toBigEndian.
/// @returns a byte array just big enough to represent @a _val.
template <class T>
inline bytes toCompactBigEndian(T _val, unsigned _min = 0)
{
static_assert(std::is_same<bigint, T>::value || !std::numeric_limits<T>::is_signed, "only unsigned types or bigint supported"); //bigint does not carry sign bit on shift
int i = 0;
for (T v = _val; v; ++i, v >>= 8) {}
bytes ret(std::max<unsigned>(_min, i), 0);
toBigEndian(_val, ret);
return ret;
}
inline bytes toCompactBigEndian(uint8_t _val, unsigned _min = 0)
{
return (_min || _val) ? bytes{ _val } : bytes{};
}
/// Convenience function for conversion of a u256 to hex
inline std::string toHex(u256 val, HexPrefix prefix = HexPrefix::DontAdd)
{
std::string str = toHex(toBigEndian(val));
return (prefix == HexPrefix::Add) ? "0x" + str : str;
}
/// Returns decimal representation for small numbers and hex for large numbers.
inline std::string formatNumber(bigint const& _value)
{
if (_value < 0)
return "-" + formatNumber(-_value);
if (_value > 0x1000000)
return toHex(toCompactBigEndian(_value), HexPrefix::Add);
else
return _value.str();
}
inline std::string formatNumber(u256 const& _value)
{
if (_value > 0x1000000)
return toHex(toCompactBigEndian(_value), HexPrefix::Add);
else
return _value.str();
}
inline std::string toCompactHexWithPrefix(u256 val)
{
std::ostringstream ret;
ret << std::hex << val;
return "0x" + ret.str();
}
// Algorithms for string and string-like collections.
/// Determine bytes required to encode the given integer value. @returns 0 if @a _i is zero.
template <class T>
inline unsigned bytesRequired(T _i)
{
static_assert(std::is_same<bigint, T>::value || !std::numeric_limits<T>::is_signed, "only unsigned types or bigint supported"); //bigint does not carry sign bit on shift
unsigned i = 0;
for (; _i != 0; ++i, _i >>= 8) {}
return i;
}
template <class T, class V>
bool contains(T const& _t, V const& _v)
{
return std::end(_t) != std::find(std::begin(_t), std::end(_t), _v);
}
template <class T, class Predicate>
bool contains_if(T const& _t, Predicate const& _p)
{
return std::end(_t) != std::find_if(std::begin(_t), std::end(_t), _p);
}
/// Function that iterates over a vector, calling a function on each of its
/// elements. If that function returns a vector, the element is replaced by
/// the returned vector. During the iteration, the original vector is only valid
/// on the current element and after that. The actual replacement takes
/// place at the end, but already visited elements might be invalidated.
/// If nothing is replaced, no copy is performed.
template <typename T, typename F>
void iterateReplacing(std::vector<T>& _vector, F const& _f)
{
// Concept: _f must be Callable, must accept param T&, must return optional<vector<T>>
bool useModified = false;
std::vector<T> modifiedVector;
for (size_t i = 0; i < _vector.size(); ++i)
{
if (std::optional<std::vector<T>> r = _f(_vector[i]))
{
if (!useModified)
{
std::move(_vector.begin(), _vector.begin() + i, back_inserter(modifiedVector));
useModified = true;
}
modifiedVector += std::move(*r);
}
else if (useModified)
modifiedVector.emplace_back(std::move(_vector[i]));
}
if (useModified)
_vector = std::move(modifiedVector);
}
namespace detail
{
template <typename T, typename F, std::size_t... I>
void iterateReplacingWindow(std::vector<T>& _vector, F const& _f, std::index_sequence<I...>)
{
// Concept: _f must be Callable, must accept sizeof...(I) parameters of type T&, must return optional<vector<T>>
bool useModified = false;
std::vector<T> modifiedVector;
size_t i = 0;
for (; i + sizeof...(I) <= _vector.size(); ++i)
{
if (std::optional<std::vector<T>> r = _f(_vector[i + I]...))
{
if (!useModified)
{
std::move(_vector.begin(), _vector.begin() + i, back_inserter(modifiedVector));
useModified = true;
}
modifiedVector += std::move(*r);
i += sizeof...(I) - 1;
}
else if (useModified)
modifiedVector.emplace_back(std::move(_vector[i]));
}
if (useModified)
{
for (; i < _vector.size(); ++i)
modifiedVector.emplace_back(std::move(_vector[i]));
_vector = std::move(modifiedVector);
}
}
}
/// Function that iterates over the vector @param _vector,
/// calling the function @param _f on sequences of @tparam N of its
/// elements. If @param _f returns a vector, these elements are replaced by
/// the returned vector and the iteration continues with the next @tparam N elements.
/// If the function does not return a vector, the iteration continues with an overlapping
/// sequence of @tparam N elements that starts with the second element of the previous
/// iteration.
/// During the iteration, the original vector is only valid
/// on the current element and after that. The actual replacement takes
/// place at the end, but already visited elements might be invalidated.
/// If nothing is replaced, no copy is performed.
template <std::size_t N, typename T, typename F>
void iterateReplacingWindow(std::vector<T>& _vector, F const& _f)
{
// Concept: _f must be Callable, must accept N parameters of type T&, must return optional<vector<T>>
detail::iterateReplacingWindow(_vector, _f, std::make_index_sequence<N>{});
}
/// @returns true iff @a _str passess the hex address checksum test.
/// @param _strict if false, hex strings with only uppercase or only lowercase letters
/// are considered valid.
bool passesAddressChecksum(std::string const& _str, bool _strict);
/// @returns the checksummed version of an address
/// @param hex strings that look like an address
std::string getChecksummedAddress(std::string const& _addr);
bool isValidHex(std::string const& _string);
bool isValidDecimal(std::string const& _string);
template<typename Container, typename Compare>
bool containerEqual(Container const& _lhs, Container const& _rhs, Compare&& _compare)
{
return std::equal(std::begin(_lhs), std::end(_lhs), std::begin(_rhs), std::end(_rhs), std::forward<Compare>(_compare));
}
inline std::string findAnyOf(std::string const& _haystack, std::vector<std::string> const& _needles)
{
for (std::string const& needle: _needles)
if (_haystack.find(needle) != std::string::npos)
return needle;
return "";
}
namespace detail
{
template<typename T>
void variadicEmplaceBack(std::vector<T>&) {}
template<typename T, typename A, typename... Args>
void variadicEmplaceBack(std::vector<T>& _vector, A&& _a, Args&&... _args)
{
_vector.emplace_back(std::forward<A>(_a));
variadicEmplaceBack(_vector, std::forward<Args>(_args)...);
}
}
template<typename T, typename... Args>
std::vector<T> make_vector(Args&&... _args)
{
std::vector<T> result;
result.reserve(sizeof...(_args));
detail::variadicEmplaceBack(result, std::forward<Args>(_args)...);
return result;
}
}