Splitting out CharStream from Scanner.

1 files changed, 100 insertions, 0 deletions

diff --git a/liblangutil/CharStream.h b/liblangutil/CharStream.h
new file mode 100644
index 00000000..7c5488a0
--- /dev/null
+++ b/liblangutil/CharStream.h
@@ -0,0 +1,100 @@
+/*
+	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.h", 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.
+ */
+
+#pragma once
+
+#include <cstdint>
+#include <string>
+#include <tuple>
+
+namespace dev
+{
+namespace solidity
+{
+
+/**
+ * Bidirectional stream of characters.
+ *
+ * This CharStream is used by lexical analyzers as the source.
+ */
+class CharStream
+{
+public:
+	CharStream(): m_position(0) {}
+	explicit CharStream(std::string const& _source): m_source(_source), m_position(0) {}
+
+	int position() const { return m_position; }
+	bool isPastEndOfInput(size_t _charsForward = 0) const { return (m_position + _charsForward) >= m_source.size(); }
+
+	char get(size_t _charsForward = 0) const { return m_source[m_position + _charsForward]; }
+	char advanceAndGet(size_t _chars = 1);
+	char rollback(size_t _amount);
+
+	void reset() { m_position = 0; }
+
+	std::string const& source() const { return m_source; }
+
+	///@{
+	///@name Error printing helper functions
+	/// Functions that help pretty-printing parse errors
+	/// Do only use in error cases, they are quite expensive.
+	std::string lineAtPosition(int _position) const;
+	std::tuple<int, int> translatePositionToLineColumn(int _position) const;
+	///@}
+
+private:
+	std::string m_source;
+	size_t m_position;
+};
+
+}
+}