Extract file reading logic from CommandLineInterface into FileReader class.

libsolidity/interface/FileReader.h

@@ -0,0 +1,90 @@
+/*
+	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/ImportRemapper.h>
+#include <libsolidity/interface/ReadFile.h>
+
+#include <boost/filesystem.hpp>
+
+#include <map>
+#include <set>
+
+namespace solidity::frontend
+{
+
+/// FileReader - used for progressively loading source code.
+///
+/// It is used in solc to load files from CLI parameters, stdin, or from JSON and
+/// also used in the solc language server where solc is a long running process.
+class FileReader
+{
+public:
+	using StringMap = std::map<SourceUnitName, SourceCode>;
+	using PathMap = std::map<SourceUnitName, boost::filesystem::path>;
+	using FileSystemPathSet = std::set<boost::filesystem::path>;
+
+	/// Constructs a FileReader with a base path and a set of allowed directories that
+	/// will be used when requesting files from this file reader instance.
+	explicit FileReader(
+		boost::filesystem::path _basePath = {},
+		FileSystemPathSet _allowedDirectories = {}
+	):
+		m_basePath(std::move(_basePath)),
+		m_allowedDirectories(std::move(_allowedDirectories)),
+		m_sourceCodes()
+	{}
+
+	void setBasePath(boost::filesystem::path _path) { m_basePath = std::move(_path); }
+	boost::filesystem::path const& basePath() const noexcept { return m_basePath; }
+
+	void allowDirectory(boost::filesystem::path _path) { m_allowedDirectories.insert(std::move(_path)); }
+	FileSystemPathSet const& allowedDirectories() const noexcept { return m_allowedDirectories; }
+
+	StringMap const& sourceCodes() const noexcept { return m_sourceCodes; }
+
+	/// Retrieves the source code for a given source unit ID.
+	SourceCode const& sourceCode(SourceUnitName const& _sourceUnitName) const { return m_sourceCodes.at(_sourceUnitName); }
+
+	/// Resets all sources to the given map of source unit ID to source codes.
+	void setSources(StringMap _sources);
+
+	/// Adds the source code for a given source unit ID.
+	void setSource(boost::filesystem::path const& _path, SourceCode _source);
+
+	/// Reads a given file at @p _path of kind @p _kind from the local filesystem and returns the result.
+	/// @p _kind must always be passed as "source".
+	frontend::ReadCallback::Result readFile(std::string const& _kind, std::string const& _path);
+
+	frontend::ReadCallback::Callback reader()
+	{
+		return [this](std::string const& _kind, std::string const& _path) { return readFile(_kind, _path); };
+	}
+
+private:
+	/// Base path, used for resolving relative paths in imports.
+	boost::filesystem::path m_basePath;
+
+	/// list of allowed directories to read files from
+	FileSystemPathSet m_allowedDirectories;
+
+	/// map of input files to source code strings
+	StringMap m_sourceCodes;
+};
+
+}