Add CowTree for storing chunk index data

Also, add a a real implementation of LeafStore, with persistence.

1 files changed, 41 insertions, 0 deletions

diff --git a/obnamlib/fmt_ga/cowtree.py b/obnamlib/fmt_ga/cowtree.py
new file mode 100644
index 00000000..7500b089
--- /dev/null
+++ b/obnamlib/fmt_ga/cowtree.py
@@ -0,0 +1,41 @@
+# Copyright 2016  Lars Wirzenius
+#
+# 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/>.
+#
+# =*= License: GPL-3+ =*=
+
+
+import obnamlib
+
+
+class CowTree(object):
+
+    def __init__(self):
+        self._store = None
+        self._leaf = obnamlib.CowLeaf()
+
+    def set_leaf_store(self, leaf_store):
+        self._store = leaf_store
+
+    def set_list_node(self, leaf_id):
+        self._leaf = self._store.get_leaf(leaf_id)
+
+    def lookup(self, key):
+        return self._leaf.lookup(key)
+
+    def insert(self, key, value):
+        self._leaf.insert(key, value)
+
+    def commit(self):
+        return self._store.put_leaf(self._leaf)