1 files changed, 72 insertions, 0 deletions
diff --git a/src/core/parser/stack/TokenRegistry.cpp b/src/core/parser/stack/TokenRegistry.cpp
new file mode 100644
index 0000000..21ae109
--- /dev/null
+++ b/src/core/parser/stack/TokenRegistry.cpp
@@ -0,0 +1,72 @@
+/*
+    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/>.
+*/
+
+#include "TokenRegistry.hpp"
+
+namespace ousia {
+namespace parser_stack {
+
+TokenId TokenRegistry::registerToken(const std::string &token)
+{
+	// Check whether the given token is already registered
+	auto it = tokens.find(token);
+	if (it != tokens.end()) {
+		// Increment the reference count
+		size_t &refCount = it->second.second;
+		refCount++;
+
+		// Return the token id
+		return it->second.first;
+	}
+
+	// Register the token in the parser
+	TokenId id = parser.registerToken(token);
+	tokens[token] = std::pair<TokenId, size_t>(id, 1);
+	tokenIds[id] = token;
+	return id;
+}
+
+void TokenRegistry::unregisterToken(TokenId id)
+{
+	// Lookup the token corresponding to the given token id
+	auto tokenIt = tokenIds.find(id);
+	if (tokenIt != tokenIds.end()) {
+		const std::string &token = tokenIt->second;
+		// Lookup the reference count for the corresponding token
+		auto idIt = tokens.find(token);
+		if (idIt != tokens.end()) {
+			// Decrement the reference count, abort if the refCount is larger
+			// than zero
+			size_t &refCount = idIt->second.second;
+			refCount--;
+			if (refCount > 0) {
+				return;
+			}
+
+			// Unregister the token from the parser
+			parser.unregisterToken(id);
+
+			// Unregister the token from the internal tokens map
+			tokens.erase(token);
+		}
+		// Unregister the token from the internal id map
+		tokenIds.erase(id);
+	}
+}
+}
+}