1 files changed, 95 insertions, 0 deletions
diff --git a/utils/config/parser.hpp b/utils/config/parser.hpp
new file mode 100644
index 000000000000..cb69e756cbe8
--- /dev/null
+++ b/utils/config/parser.hpp
@@ -0,0 +1,95 @@
+// Copyright 2012 The Kyua 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.
+
+/// \file utils/config/parser.hpp
+/// Utilities to read a configuration file into memory.
+
+#if !defined(UTILS_CONFIG_PARSER_HPP)
+#define UTILS_CONFIG_PARSER_HPP
+
+#include "utils/config/parser_fwd.hpp"
+
+#include <memory>
+
+#include "utils/config/tree_fwd.hpp"
+#include "utils/fs/path_fwd.hpp"
+#include "utils/noncopyable.hpp"
+
+namespace utils {
+namespace config {
+
+
+/// A configuration parser.
+///
+/// This parser is a class rather than a function because we need to support
+/// callbacks to perform the initialization of the config file schema.  The
+/// configuration files always start with a call to syntax(), which define the
+/// particular version of the schema being used.  Depending on such version, the
+/// layout of the internal tree representation needs to be different.
+///
+/// A parser implementation must provide a setup() method to set up the
+/// configuration schema based on the particular combination of syntax format
+/// and version specified on the file.
+///
+/// Parser objects are not supposed to be reused, and specific trees are not
+/// supposed to be passed to multiple parsers (even if sequentially).  Doing so
+/// will cause all kinds of inconsistencies in the managed tree itself or in the
+/// Lua state.
+class parser : noncopyable {
+public:
+    struct impl;
+
+private:
+    /// Pointer to the internal implementation.
+    std::auto_ptr< impl > _pimpl;
+
+    /// Hook to initialize the tree keys before reading the file.
+    ///
+    /// This hook gets called when the configuration file defines its specific
+    /// format by calling the syntax() function.  We have to delay the tree
+    /// initialization until this point because, before we know what version of
+    /// a configuration file we are parsing, we cannot know what keys are valid.
+    ///
+    /// \param [in,out] config_tree The tree in which to define the key
+    ///     structure.
+    /// \param syntax_version The version of the file format as specified in the
+    ///     configuration file.
+    virtual void setup(tree& config_tree, const int syntax_version) = 0;
+
+public:
+    explicit parser(tree&);
+    virtual ~parser(void);
+
+    void parse(const fs::path&);
+};
+
+
+}  // namespace config
+}  // namespace utils
+
+#endif  // !defined(UTILS_CONFIG_PARSER_HPP)