Splitting out CharStream from Scanner.

1 files changed, 115 insertions, 0 deletions

diff --git a/liblangutil/CharStream.cpp b/liblangutil/CharStream.cpp
new file mode 100644
index 00000000..04490fa6
--- /dev/null
+++ b/liblangutil/CharStream.cpp
@@ -0,0 +1,115 @@
+/*
+	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
+	  with the distribution.
+	* 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,
+	SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+	LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+	DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+	THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+	(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+	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>
+#include <algorithm>
+#include <tuple>
+
+using namespace std;
+
+namespace dev
+{
+namespace solidity
+{
+
+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();
+}
+
+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(), _position);
+	if (searchStart > 0)
+		searchStart--;
+	size_type lineStart = m_source.rfind('\n', searchStart);
+	if (lineStart == string::npos)
+		lineStart = 0;
+	else
+		lineStart++;
+	return m_source.substr(lineStart, min(m_source.find('\n', lineStart),
+										  m_source.size()) - lineStart);
+}
+
+tuple<int, int> CharStream::translatePositionToLineColumn(int _position) const
+{
+	using size_type = string::size_type;
+	size_type searchPosition = min<size_type>(m_source.size(), _position);
+	int lineNumber = count(m_source.begin(), m_source.begin() + 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);
+}
+
+}
+}