Add tool to find scan roots.
Bug: 73625480
Change-Id: I93b405feb999aaed9675d2ea52712663fa83c9e0
diff --git a/tools/find_scan_roots.py b/tools/find_scan_roots.py
new file mode 100755
index 0000000..c17a9f2
--- /dev/null
+++ b/tools/find_scan_roots.py
@@ -0,0 +1,94 @@
+#!/usr/bin/env python
+# Copyright (C) 2018 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Takes output of
+# adb shell 'find /data -print0 | xargs -0 ls -ldZ' | awk '{print $5 " " $9}'
+# in standard input and generates list of directories we need to scan to cover
+# the labels given on the command line.
+
+import sys
+import argparse
+
+class Node(object):
+ def __init__(self, name, label=None):
+ self.name = name
+ self.label = label
+ self.marked = False
+ self.children = {}
+
+ def Find(self, components):
+ if not components:
+ return self
+
+ child = components[0]
+ if child in self.children:
+ return self.children[child].Find(components[1:])
+
+ n = Node(child)
+ self.children[child] = n
+ return n
+
+ def __iter__(self):
+ for child in self.children.itervalues():
+ yield self.name + '/' + child.name, child
+ for p, ch in child:
+ yield self.name + '/' + p, ch
+
+ def Mark(self, labels):
+ # Either incorrect label or already marked, we do not need to scan
+ # this path.
+ if self.marked or self.label not in labels:
+ return False
+
+ self.marked = True
+
+ for child in self.children.itervalues():
+ child.Mark(labels)
+
+ return True
+
+
+def BuildTree(stream=sys.stdin):
+ root = Node("")
+
+ for line in stream:
+ line = line.strip()
+ if not line:
+ continue
+
+ label, path = line.split(' ', 1)
+ # u:object_r:system_data_file:s0 -> system_data_file.
+ sanitized_label = label.split(':')[2]
+ # Strip leading slash.
+ components = path[1:].split('/')
+
+ n = root.Find(components)
+ n.label = sanitized_label
+ return root
+
+
+def main():
+ parser = argparse.ArgumentParser()
+ parser.add_argument('labels', metavar='L', type=str, nargs='+',
+ help='labels we want to find')
+ args = parser.parse_args()
+ root = BuildTree()
+ for fullpath, elem in root:
+ if elem.Mark(args.labels):
+ print fullpath
+
+
+if __name__ == '__main__':
+ main()
