1#!/usr/bin/env python
2#
3# Copyright (C) 2012 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
17"""Generates default implementations of operator<< for enum types."""
18
19import codecs
20import os
21import re
22import string
23import sys
24
25
26_ENUM_START_RE = re.compile(r'\benum\b\s+(class\s+)?(\S+)\s+:?.*\{(\s+// private)?')
27_ENUM_VALUE_RE = re.compile(r'([A-Za-z0-9_]+)(.*)')
28_ENUM_END_RE = re.compile(r'^\s*\};$')
29_ENUMS = {}
30_NAMESPACES = {}
31_ENUM_CLASSES = {}
32
33def Confused(filename, line_number, line):
34  sys.stderr.write('%s:%d: confused by:\n%s\n' % (filename, line_number, line))
35  raise Exception("giving up!")
36  sys.exit(1)
37
38
39def ProcessFile(filename):
40  lines = codecs.open(filename, 'r', 'utf8', 'replace').read().split('\n')
41  in_enum = False
42  is_enum_class = False
43  line_number = 0
44
45
46  namespaces = []
47  enclosing_classes = []
48
49  for raw_line in lines:
50    line_number += 1
51
52    if not in_enum:
53      # Is this the start of a new enum?
54      m = _ENUM_START_RE.search(raw_line)
55      if m:
56        # Yes, so add an empty entry to _ENUMS for this enum.
57
58        # Except when it's private
59        if m.group(3) is not None:
60          continue
61
62        is_enum_class = m.group(1) is not None
63        enum_name = m.group(2)
64        if len(enclosing_classes) > 0:
65          enum_name = '::'.join(enclosing_classes) + '::' + enum_name
66        _ENUMS[enum_name] = []
67        _NAMESPACES[enum_name] = '::'.join(namespaces)
68        _ENUM_CLASSES[enum_name] = is_enum_class
69        in_enum = True
70        continue
71
72      # Is this the start or end of a namespace?
73      m = re.compile(r'^namespace (\S+) \{').search(raw_line)
74      if m:
75        namespaces.append(m.group(1))
76        continue
77      m = re.compile(r'^\}\s+// namespace').search(raw_line)
78      if m:
79        namespaces = namespaces[0:len(namespaces) - 1]
80        continue
81
82      # Is this the start or end of an enclosing class or struct?
83      m = re.compile(r'^(?:class|struct)(?: MANAGED)? (\S+).* \{').search(raw_line)
84      if m:
85        enclosing_classes.append(m.group(1))
86        continue
87      m = re.compile(r'^\};').search(raw_line)
88      if m:
89        enclosing_classes = enclosing_classes[0:len(enclosing_classes) - 1]
90        continue
91
92      continue
93
94    # Is this the end of the current enum?
95    m = _ENUM_END_RE.search(raw_line)
96    if m:
97      if not in_enum:
98        Confused(filename, line_number, raw_line)
99      in_enum = False
100      continue
101
102    # The only useful thing in comments is the <<alternate text>> syntax for
103    # overriding the default enum value names. Pull that out...
104    enum_text = None
105    m_comment = re.compile(r'// <<(.*?)>>').search(raw_line)
106    if m_comment:
107      enum_text = m_comment.group(1)
108    # ...and then strip // comments.
109    line = re.sub(r'//.*', '', raw_line)
110
111    # Strip whitespace.
112    line = line.strip()
113
114    # Skip blank lines.
115    if len(line) == 0:
116      continue
117
118    # Since we know we're in an enum type, and we're not looking at a comment
119    # or a blank line, this line should be the next enum value...
120    m = _ENUM_VALUE_RE.search(line)
121    if not m:
122      Confused(filename, line_number, raw_line)
123    enum_value = m.group(1)
124
125    # By default, we turn "kSomeValue" into "SomeValue".
126    if enum_text == None:
127      enum_text = enum_value
128      if enum_text.startswith('k'):
129        enum_text = enum_text[1:]
130
131    # Lose literal values because we don't care; turn "= 123, // blah" into ", // blah".
132    rest = m.group(2).strip()
133    m_literal = re.compile(r'= (0x[0-9a-f]+|-?[0-9]+|\'.\')').search(rest)
134    if m_literal:
135      rest = rest[(len(m_literal.group(0))):]
136
137    # With "kSomeValue = kOtherValue," we take the original and skip later synonyms.
138    # TODO: check that the rhs is actually an existing value.
139    if rest.startswith('= k'):
140      continue
141
142    # Remove any trailing comma and whitespace
143    if rest.startswith(','):
144      rest = rest[1:]
145    rest = rest.strip()
146
147    # There shouldn't be anything left.
148    if len(rest):
149      Confused(filename, line_number, raw_line)
150
151    if len(enclosing_classes) > 0:
152      if is_enum_class:
153        enum_value = enum_name + '::' + enum_value
154      else:
155        enum_value = '::'.join(enclosing_classes) + '::' + enum_value
156
157    _ENUMS[enum_name].append((enum_value, enum_text))
158
159def main():
160  local_path = sys.argv[1]
161  header_files = []
162  for header_file in sys.argv[2:]:
163    header_files.append(header_file)
164    ProcessFile(header_file)
165
166  print('#include <iostream>')
167  print('')
168
169  for header_file in header_files:
170    header_file = header_file.replace(local_path + '/', '')
171    print('#include "%s"' % header_file)
172
173  print('')
174
175  for enum_name in _ENUMS:
176    print('// This was automatically generated by %s --- do not edit!' % sys.argv[0])
177
178    namespaces = _NAMESPACES[enum_name].split('::')
179    for namespace in namespaces:
180      print('namespace %s {' % namespace)
181
182    print('std::ostream& operator<<(std::ostream& os, const %s& rhs) {' % enum_name)
183    print('  switch (rhs) {')
184    for (enum_value, enum_text) in _ENUMS[enum_name]:
185      print('    case %s: os << "%s"; break;' % (enum_value, enum_text))
186    if not _ENUM_CLASSES[enum_name]:
187      print('    default: os << "%s[" << static_cast<int>(rhs) << "]"; break;' % enum_name)
188    print('  }')
189    print('  return os;')
190    print('}')
191
192    for namespace in reversed(namespaces):
193      print('}  // namespace %s' % namespace)
194    print('')
195
196  sys.exit(0)
197
198
199if __name__ == '__main__':
200  main()
201