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diff --git a/src/core/common/SourceContextReader.hpp b/src/core/common/SourceContextReader.hpp
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+/*
+    Ousía
+    Copyright (C) 2014, 2015  Benjamin Paaßen, Andreas Stöckel
+
+    This program 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.
+
+    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/>.
+*/
+
+/**
+ * @file SourceContextReader.hpp
+ *
+ * The SourceContextReader class is used to read a SourceContext struct from
+ * a SourcePosition instance and an input stream.
+ *
+ * @author Andreas Stöckel (astoecke@techfak.uni-bielefeld.de)
+ */
+
+#ifndef _OUSIA_SOURCE_CONTEXT_READER_HPP_
+#define _OUSIA_SOURCE_CONTEXT_READER_HPP_
+
+#include <string>
+#include <vector>
+#include <limits>
+
+#include "Location.hpp"
+
+namespace ousia {
+
+// Forward declarations
+class CharReader;
+
+/**
+ * The SourceContextReader can read SourceContext structures given a
+ * SourcePosition or SourceRange and a char reader. It is capable of managing
+ * a line number cache which speeds up repeated context lookups.
+ */
+class SourceContextReader {
+private:
+	/**
+	 * Cache containing the byte offset of each line break.
+	 */
+	std::vector<SourceOffset> cache;
+
+public:
+	/**
+	 * Maximum context size. Used to indicate that the context should have an
+	 * unlimited size.
+	 */
+	static constexpr size_t MAX_MAX_CONTEXT_LENGTH =
+	    std::numeric_limits<ssize_t>::max();
+
+	/**
+	 * Default constructor. Initializes the internal lineNumberCache with a
+	 * single zero entry.
+	 */
+	SourceContextReader();
+
+	/**
+	 * Returns the context for the char reader and the given SourceRange.
+	 * Returns an invalid source context if either the given range is invalid
+	 * or the byte offset described in the SourceRange cannot be reached because
+	 * the CharReader cannot be seeked back to this position.
+	 *
+	 * @param reader is the CharReader instance from which the context should be
+	 * read.
+	 * @param range describes the Range within the source file for which the
+	 * context should be extraced.
+	 * @param filename is the filename that should be stored in the returned
+	 * context.
+	 * @param maxContextLength is the maximum number of characters that should
+	 * be stored in the returned context.
+	 * @return a SourceContext instance describing the
+	 */
+	SourceContext readContext(CharReader &reader, const SourceRange &range,
+	                          size_t maxContextLength = MAX_MAX_CONTEXT_LENGTH,
+	                          const std::string &filename = "");
+};
+}
+
+#endif /* _OUSIA_SOURCE_CONTEXT_READER_HPP_ */
+