1#
2# Copyright 2012, The Android Open Source Project
3#
4# Licensed under the Apache License, Version 2.0 (the "License");
5# you may not use this file except in compliance with the License.
6# You may obtain a copy of the License at
7#
8#     http://www.apache.org/licenses/LICENSE-2.0
9#
10# Unless required by applicable law or agreed to in writing, software
11# distributed under the License is distributed on an "AS IS" BASIS,
12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13# See the License for the specific language governing permissions and
14# limitations under the License.
15
16"""Data structure for processing makefiles."""
17
18import os
19
20import android_build
21import android_mk
22import errors
23
24class MakeNode(object):
25  """Represents single node in make tree."""
26
27  def __init__(self, name, parent):
28    self._name = name
29    self._children_map = {}
30    self._is_leaf = False
31    self._parent = parent
32    self._includes_submake = None
33    if parent:
34      self._path = os.path.join(parent._GetPath(), name)
35    else:
36      self._path = ""
37
38  def _AddPath(self, path_segs):
39    """Adds given path to this node.
40
41    Args:
42      path_segs: list of path segments
43    """
44    if not path_segs:
45      # done processing path
46      return self
47    current_seg = path_segs.pop(0)
48    child = self._children_map.get(current_seg)
49    if not child:
50      child = MakeNode(current_seg, self)
51      self._children_map[current_seg] = child
52    return child._AddPath(path_segs)
53
54  def _SetLeaf(self, is_leaf):
55    self._is_leaf = is_leaf
56
57  def _GetPath(self):
58    return self._path
59
60  def _DoesIncludesSubMake(self):
61    if self._includes_submake is None:
62      if self._is_leaf:
63        path = os.path.join(android_build.GetTop(), self._path)
64        mk_parser = android_mk.CreateAndroidMK(path)
65        self._includes_submake = mk_parser.IncludesMakefilesUnder()
66      else:
67        self._includes_submake = False
68    return self._includes_submake
69
70  def _DoesParentIncludeMe(self):
71    return self._parent and self._parent._DoesIncludesSubMake()
72
73  def _BuildPrunedMakeList(self, make_list):
74    if self._is_leaf and not self._DoesParentIncludeMe():
75      make_list.append(os.path.join(self._path, "Android.mk"))
76    for child in self._children_map.itervalues():
77      child._BuildPrunedMakeList(make_list)
78
79
80class MakeTree(MakeNode):
81  """Data structure for building a non-redundant set of Android.mk paths.
82
83  Used to collapse set of Android.mk files to use to prevent issuing make
84  command that include same module multiple times due to include rules.
85  """
86
87  def __init__(self):
88    super(MakeTree, self).__init__("", None)
89
90  def AddPath(self, path):
91    """Adds make directory path to tree.
92
93    Will have no effect if path is already included in make set.
94
95    Args:
96      path: filesystem path to directory to build, relative to build root.
97    """
98    path = os.path.normpath(path)
99    mk_path = os.path.join(android_build.GetTop(), path, "Android.mk")
100    if not os.path.isfile(mk_path):
101      raise errors.AbortError("%s does not exist" % mk_path)
102    path_segs = path.split(os.sep)
103    child = self._AddPath(path_segs)
104    child._SetLeaf(True)
105
106  def GetPrunedMakeList(self):
107    """Return as list of the minimum set of Android.mk files necessary to
108    build all leaf nodes in tree.
109    """
110    make_list = []
111    self._BuildPrunedMakeList(make_list)
112    return make_list
113
114  def IsEmpty(self):
115    return not self._children_map
116
117