/**
* Relational pipes (library)
* Copyright © 2018 František Kučera (Frantovo.cz, GlobalCode.info)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the:
* - GNU Lesser General Public License as published by the Free Software Foundation;
* version 3 of the License or (at your option)
* - GNU General Public License as published by the Free Software Foundation;
* version 2 of the License.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <string>
#include <iostream>
#include <cassert>
#include <limits>
#include <relpipe/protocol/constants.h>
#include "../../include/relpipe/reader/RelpipeReaderException.h"
#include "../../include/relpipe/reader/typedefs.h"
#include "../DataTypeReader.h"
namespace relpipe {
namespace reader {
namespace types {
using namespace relpipe::protocol;
using namespace relpipe::reader;
/**
* Signed variable-length integer.
* LEB128
*/
class IntegerDataTypeReader : public DataTypeReader<integer_t> {
private:
octet_t readNextOctet(std::istream &input) {
octet_t value = input.get();
if (input.good()) return value;
else throw RelpipeReaderException(L"Unable to read next octet of the integer.");
}
public:
IntegerDataTypeReader() : DataTypeReader<integer_t>(TypeId::INTEGER, DATA_TYPE_CODE_INTEGER) {
}
integer_t readValue(std::istream &input) override {
static const integer_t ZERO = 0;
integer_t value = 0;
integer_t shift = 0;
octet_t octet;
do {
octet = readNextOctet(input);
value += integer_t(octet & 0x7F) << shift;
shift += 7;
} while (octet >= 128);
if ((shift < (sizeof (integer_t) * 8)) && (octet & 0x40))
value |= (~ZERO << shift);
return value;
}
string_t toString(const integer_t &value) override {
return std::to_wstring(value);
}
};
}
}
}