GN: Make chrome/{browser,common,renderer} compile on mac
[chromium-blink-merge.git] / tools / sort-headers.py
blob07c7f24d37b3c9bc8fd419c3c457c16f1c93bb49
1 #!/usr/bin/env python
2 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
3 # Use of this source code is governed by a BSD-style license that can be
4 # found in the LICENSE file.
6 """Given a filename as an argument, sort the #include/#imports in that file.
8 Shows a diff and prompts for confirmation before doing the deed.
9 Works great with tools/git/for-all-touched-files.py.
10 """
12 import optparse
13 import os
14 import sys
17 def YesNo(prompt):
18 """Prompts with a yes/no question, returns True if yes."""
19 print prompt,
20 sys.stdout.flush()
21 # http://code.activestate.com/recipes/134892/
22 if sys.platform == 'win32':
23 import msvcrt
24 ch = msvcrt.getch()
25 else:
26 import termios
27 import tty
28 fd = sys.stdin.fileno()
29 old_settings = termios.tcgetattr(fd)
30 ch = 'n'
31 try:
32 tty.setraw(sys.stdin.fileno())
33 ch = sys.stdin.read(1)
34 finally:
35 termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
36 print ch
37 return ch in ('Y', 'y')
40 def IncludeCompareKey(line):
41 """Sorting comparator key used for comparing two #include lines.
42 Returns the filename without the #include/#import/import prefix.
43 """
44 for prefix in ('#include ', '#import ', 'import '):
45 if line.startswith(prefix):
46 line = line[len(prefix):]
47 break
49 # The win32 api has all sorts of implicit include order dependencies :-/
50 # Give a few headers special sort keys that make sure they appear before all
51 # other headers.
52 if line.startswith('<windows.h>'): # Must be before e.g. shellapi.h
53 return '0'
54 if line.startswith('<atlbase.h>'): # Must be before atlapp.h.
55 return '1' + line
56 if line.startswith('<unknwn.h>'): # Must be before e.g. intshcut.h
57 return '1' + line
59 # C++ system headers should come after C system headers.
60 if line.startswith('<'):
61 if line.find('.h>') != -1:
62 return '2' + line.lower()
63 else:
64 return '3' + line.lower()
66 return '4' + line
69 def IsInclude(line):
70 """Returns True if the line is an #include/#import/import line."""
71 return any([line.startswith('#include '), line.startswith('#import '),
72 line.startswith('import ')])
75 def SortHeader(infile, outfile):
76 """Sorts the headers in infile, writing the sorted file to outfile."""
77 for line in infile:
78 if IsInclude(line):
79 headerblock = []
80 while IsInclude(line):
81 infile_ended_on_include_line = False
82 headerblock.append(line)
83 # Ensure we don't die due to trying to read beyond the end of the file.
84 try:
85 line = infile.next()
86 except StopIteration:
87 infile_ended_on_include_line = True
88 break
89 for header in sorted(headerblock, key=IncludeCompareKey):
90 outfile.write(header)
91 if infile_ended_on_include_line:
92 # We already wrote the last line above; exit to ensure it isn't written
93 # again.
94 return
95 # Intentionally fall through, to write the line that caused
96 # the above while loop to exit.
97 outfile.write(line)
100 def FixFileWithConfirmFunction(filename, confirm_function,
101 perform_safety_checks):
102 """Creates a fixed version of the file, invokes |confirm_function|
103 to decide whether to use the new file, and cleans up.
105 |confirm_function| takes two parameters, the original filename and
106 the fixed-up filename, and returns True to use the fixed-up file,
107 false to not use it.
109 If |perform_safety_checks| is True, then the function checks whether it is
110 unsafe to reorder headers in this file and skips the reorder with a warning
111 message in that case.
113 if perform_safety_checks and IsUnsafeToReorderHeaders(filename):
114 print ('Not reordering headers in %s as the script thinks that the '
115 'order of headers in this file is semantically significant.'
116 % (filename))
117 return
118 fixfilename = filename + '.new'
119 infile = open(filename, 'rb')
120 outfile = open(fixfilename, 'wb')
121 SortHeader(infile, outfile)
122 infile.close()
123 outfile.close() # Important so the below diff gets the updated contents.
125 try:
126 if confirm_function(filename, fixfilename):
127 if sys.platform == 'win32':
128 os.unlink(filename)
129 os.rename(fixfilename, filename)
130 finally:
131 try:
132 os.remove(fixfilename)
133 except OSError:
134 # If the file isn't there, we don't care.
135 pass
138 def DiffAndConfirm(filename, should_confirm, perform_safety_checks):
139 """Shows a diff of what the tool would change the file named
140 filename to. Shows a confirmation prompt if should_confirm is true.
141 Saves the resulting file if should_confirm is false or the user
142 answers Y to the confirmation prompt.
144 def ConfirmFunction(filename, fixfilename):
145 diff = os.system('diff -u %s %s' % (filename, fixfilename))
146 if sys.platform != 'win32':
147 diff >>= 8
148 if diff == 0: # Check exit code.
149 print '%s: no change' % filename
150 return False
152 return (not should_confirm or YesNo('Use new file (y/N)?'))
154 FixFileWithConfirmFunction(filename, ConfirmFunction, perform_safety_checks)
156 def IsUnsafeToReorderHeaders(filename):
157 # *_message_generator.cc is almost certainly a file that generates IPC
158 # definitions. Changes in include order in these files can result in them not
159 # building correctly.
160 if filename.find("message_generator.cc") != -1:
161 return True
162 return False
164 def main():
165 parser = optparse.OptionParser(usage='%prog filename1 filename2 ...')
166 parser.add_option('-f', '--force', action='store_false', default=True,
167 dest='should_confirm',
168 help='Turn off confirmation prompt.')
169 parser.add_option('--no_safety_checks',
170 action='store_false', default=True,
171 dest='perform_safety_checks',
172 help='Do not perform the safety checks via which this '
173 'script refuses to operate on files for which it thinks '
174 'the include ordering is semantically significant.')
175 opts, filenames = parser.parse_args()
177 if len(filenames) < 1:
178 parser.print_help()
179 return 1
181 for filename in filenames:
182 DiffAndConfirm(filename, opts.should_confirm, opts.perform_safety_checks)
185 if __name__ == '__main__':
186 sys.exit(main())