solidity/liblangutil/CharStream.cpp
2020-06-03 11:22:46 +02:00

121 lines
4.2 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/>.
*
* This file is derived from the file "scanner.cc", which was part of the
* V8 project. The original copyright header follows:
*
* Copyright 2006-2012, the V8 project authors. All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
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* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2014
* Solidity scanner.
*/
#include <liblangutil/CharStream.h>
#include <liblangutil/Exceptions.h>
using namespace std;
using namespace solidity;
using namespace solidity::langutil;
char CharStream::advanceAndGet(size_t _chars)
{
if (isPastEndOfInput())
return 0;
m_position += _chars;
if (isPastEndOfInput())
return 0;
return m_source[m_position];
}
char CharStream::rollback(size_t _amount)
{
solAssert(m_position >= _amount, "");
m_position -= _amount;
return get();
}
char CharStream::setPosition(size_t _location)
{
solAssert(_location <= m_source.size(), "Attempting to set position past end of source.");
m_position = _location;
return get();
}
string CharStream::lineAtPosition(int _position) const
{
// if _position points to \n, it returns the line before the \n
using size_type = string::size_type;
size_type searchStart = min<size_type>(m_source.size(), size_type(_position));
if (searchStart > 0)
searchStart--;
size_type lineStart = m_source.rfind('\n', searchStart);
if (lineStart == string::npos)
lineStart = 0;
else
lineStart++;
string line = m_source.substr(
lineStart,
min(m_source.find('\n', lineStart), m_source.size()) - lineStart
);
if (!line.empty() && line.back() == '\r')
line.pop_back();
return line;
}
tuple<int, int> CharStream::translatePositionToLineColumn(int _position) const
{
using size_type = string::size_type;
using diff_type = string::difference_type;
size_type searchPosition = min<size_type>(m_source.size(), size_type(_position));
int lineNumber = count(m_source.begin(), m_source.begin() + diff_type(searchPosition), '\n');
size_type lineStart;
if (searchPosition == 0)
lineStart = 0;
else
{
lineStart = m_source.rfind('\n', searchPosition - 1);
lineStart = lineStart == string::npos ? 0 : lineStart + 1;
}
return tuple<int, int>(lineNumber, searchPosition - lineStart);
}