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# Copyright (C) 2008 Canonical Ltd
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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"""B+Tree index parsing."""
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def _parse_leaf_lines(bytes, key_length, ref_list_length):
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lines = bytes.split('\n')
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for line in lines[1:]:
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elements = line.split('\0', key_length)
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key = tuple(elements[:key_length])
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references, value = line.rsplit('\0', 1)
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for ref_string in references.split('\t'):
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ref_lists.append(tuple([
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tuple(ref.split('\0')) for ref in ref_string.split('\r') if ref
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ref_lists = tuple(ref_lists)
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node_value = (value, ref_lists)
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node_value = (value, ())
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nodes.append((key, node_value))
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def _flatten_node(node, reference_lists):
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"""Convert a node into the serialized form.
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:param node: A tuple representing a node (key_tuple, value, references)
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:param reference_lists: Does this index have reference lists?
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:return: (string_key, flattened)
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string_key The serialized key for referencing this node
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flattened A string with the serialized form for the contents
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# TODO: Consider turning this back into the 'unoptimized' nested loop
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# form. It is probably more obvious for most people, and this is
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# just a reference implementation.
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flattened_references = ['\r'.join(['\x00'.join(reference)
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for reference in ref_list])
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for ref_list in node[3]]
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flattened_references = []
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string_key = '\x00'.join(node[1])
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line = ("%s\x00%s\x00%s\n" % (string_key,
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'\t'.join(flattened_references), node[2]))
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return string_key, line