Allow running Eldarica from the command line

libsolidity/interface/UniversalCallback.h

@@ -0,0 +1,53 @@
+/*
+	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/>.
+*/
+// SPDX-License-Identifier: GPL-3.0
+#pragma once
+
+#include <libsolidity/interface/FileReader.h>
+#include <libsolidity/interface/SMTSolverCommand.h>
+
+namespace solidity::frontend
+{
+
+/// UniversalCallback is used to wrap both FileReader and SMTSolverCommand
+/// callbacks in a single callback.  It uses the Kind of the callback to
+/// determine which to call internally.
+class UniversalCallback
+{
+public:
+	UniversalCallback(FileReader&  _fileReader, SMTSolverCommand& _solver) :
+		m_fileReader{_fileReader},
+		m_solver{_solver}
+	{}
+
+	frontend::ReadCallback::Callback callback()
+	{
+		return [this](std::string const& _kind, std::string const& _data) -> ReadCallback::Result {
+			if (_kind == ReadCallback::kindString(ReadCallback::Kind::ReadFile))
+				return m_fileReader.readFile(_kind, _data);
+			else if (_kind == ReadCallback::kindString(ReadCallback::Kind::SMTQuery))
+				return m_solver.solve(_kind, _data);
+			solAssert(false, "Unknown callback kind.");
+		};
+	}
+
+private:
+	FileReader& m_fileReader;
+	SMTSolverCommand& m_solver;
+};
+
+}