1 files changed, 56 insertions, 0 deletions
diff --git a/grc/converter/block_tree.py b/grc/converter/block_tree.py
new file mode 100644
index 0000000000..dee9adba49
--- /dev/null
+++ b/grc/converter/block_tree.py
@@ -0,0 +1,56 @@
+# Copyright 2016 Free Software Foundation, Inc.
+# This file is part of GNU Radio
+#
+# GNU Radio Companion 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 2 of the License, or (at your
+# option) any later version.
+#
+# GNU Radio Companion 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, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+"""
+Converter for legacy block tree definitions in XML format
+"""
+
+from __future__ import absolute_import, print_function
+
+from ..core.io import yaml
+from . import xml
+
+
+def from_xml(filename):
+    """Load block tree description from xml file"""
+    element, version_info = xml.load(filename, 'block_tree.dtd')
+
+    try:
+        data = convert_category_node(element)
+    except NameError:
+        raise ValueError('Conversion failed', filename)
+
+    return data
+
+
+def dump(data, stream):
+    out = yaml.dump(data, indent=2)
+    prefix = '# auto-generated by grc.converter\n\n'
+    stream.write(prefix + out)
+
+
+def convert_category_node(node):
+    """convert nested <cat> tags to nested lists dicts"""
+    assert node.tag == 'cat'
+    name, elements = '', []
+    for child in node:
+        if child.tag == 'name':
+            name = child.text.strip()
+        elif child.tag == 'block':
+            elements.append(child.text.strip())
+        elif child.tag == 'cat':
+            elements.append(convert_category_node(child))
+    return {name: elements}