post_process_props.py revision 38df101343137c3a4c1954803a52a4ea35c7f42f 
1#!/usr/bin/env python
2#
3# Copyright (C) 2009 The Android Open Source Project
4#
5# Licensed under the Apache License, Version 2.0 (the "License");
6# you may not use this file except in compliance with the License.
7# You may obtain a copy of the License at
8#
9#      http://www.apache.org/licenses/LICENSE-2.0
10#
11# Unless required by applicable law or agreed to in writing, software
12# distributed under the License is distributed on an "AS IS" BASIS,
13# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14# See the License for the specific language governing permissions and
15# limitations under the License.
16
17import sys
18
19# Usage: post_process_props.py file.prop [blacklist_key, ...]
20# Blacklisted keys are removed from the property file, if present
21
22# See PROP_NAME_MAX and PROP_VALUE_MAX system_properties.h.
23# The constants in system_properties.h includes the termination NUL,
24# so we decrease the values by 1 here.
25PROP_NAME_MAX = 31
26PROP_VALUE_MAX = 91
27
28# Put the modifications that you need to make into the /system/build.prop into this
29# function. The prop object has get(name) and put(name,value) methods.
30def mangle_build_prop(prop):
31  pass
32
33# Put the modifications that you need to make into the /default.prop into this
34# function. The prop object has get(name) and put(name,value) methods.
35def mangle_default_prop(prop):
36  # If ro.debuggable is 1, then enable adb on USB by default
37  # (this is for userdebug builds)
38  if prop.get("ro.debuggable") == "1":
39    val = prop.get("persist.sys.usb.config")
40    if val == "":
41      val = "adb"
42    else:
43      val = val + ",adb"
44    prop.put("persist.sys.usb.config", val)
45  # UsbDeviceManager expects a value here.  If it doesn't get it, it will
46  # default to "adb". That might not the right policy there, but it's better
47  # to be explicit.
48  if not prop.get("persist.sys.usb.config"):
49    prop.put("persist.sys.usb.config", "none");
50
51def validate(prop):
52  """Validate the properties.
53
54  Returns:
55    True if nothing is wrong.
56  """
57  check_pass = True
58  buildprops = prop.to_dict()
59  for key, value in buildprops.iteritems():
60    # Check build properties' length.
61    if len(key) > PROP_NAME_MAX:
62      check_pass = False
63      sys.stderr.write("error: %s cannot exceed %d bytes: " %
64                       (key, PROP_NAME_MAX))
65      sys.stderr.write("%s (%d)\n" % (key, len(key)))
66    if len(value) > PROP_VALUE_MAX:
67      check_pass = False
68      sys.stderr.write("error: %s cannot exceed %d bytes: " %
69                       (key, PROP_VALUE_MAX))
70      sys.stderr.write("%s (%d)\n" % (value, len(value)))
71  return check_pass
72
73class PropFile:
74
75  def __init__(self, lines):
76    self.lines = [s.strip() for s in lines]
77
78  def to_dict(self):
79    props = {}
80    for line in self.lines:
81      if not line or line.startswith("#"):
82        continue
83      if "=" in line:
84        key, value = line.split("=", 1)
85        props[key] = value
86    return props
87
88  def get(self, name):
89    key = name + "="
90    for line in self.lines:
91      if line.startswith(key):
92        return line[len(key):]
93    return ""
94
95  def put(self, name, value):
96    key = name + "="
97    for i in range(0,len(self.lines)):
98      if self.lines[i].startswith(key):
99        self.lines[i] = key + value
100        return
101    self.lines.append(key + value)
102
103  def delete(self, name):
104    key = name + "="
105    self.lines = [ line for line in self.lines if not line.startswith(key) ]
106
107  def write(self, f):
108    f.write("\n".join(self.lines))
109    f.write("\n")
110
111def main(argv):
112  filename = argv[1]
113  f = open(filename)
114  lines = f.readlines()
115  f.close()
116
117  properties = PropFile(lines)
118
119  if filename.endswith("/build.prop"):
120    mangle_build_prop(properties)
121  elif filename.endswith("/default.prop"):
122    mangle_default_prop(properties)
123  else:
124    sys.stderr.write("bad command line: " + str(argv) + "\n")
125    sys.exit(1)
126
127  if not validate(properties):
128    sys.exit(1)
129
130  # Drop any blacklisted keys
131  for key in argv[2:]:
132    properties.delete(key)
133
134  f = open(filename, 'w+')
135  properties.write(f)
136  f.close()
137
138if __name__ == "__main__":
139  main(sys.argv)
140