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. 5 6 """Given a filename as an argument, sort the #include/#imports in that file. 7 8 Shows a diff and prompts for confirmation before doing the deed. 9 Works great with tools/git/for-all-touched-files.py. 10 """ 11 12 import optparse 13 import os 14 import sys 15 16 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') 38 39 40 def IncludeCompareKey(line): 41 """Sorting comparator key used for comparing two #include lines. 42 Returns the filename without the #include/#import prefix. 43 """ 44 for prefix in ('#include ', '#import '): 45 if line.startswith(prefix): 46 line = line[len(prefix):] 47 break 48 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 58 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() 65 66 return '4' + line 67 68 69 def IsInclude(line): 70 """Returns True if the line is an #include/#import line.""" 71 return line.startswith('#include ') or line.startswith('#import ') 72 73 74 def SortHeader(infile, outfile): 75 """Sorts the headers in infile, writing the sorted file to outfile.""" 76 for line in infile: 77 if IsInclude(line): 78 headerblock = [] 79 while IsInclude(line): 80 infile_ended_on_include_line = False 81 headerblock.append(line) 82 # Ensure we don't die due to trying to read beyond the end of the file. 83 try: 84 line = infile.next() 85 except StopIteration: 86 infile_ended_on_include_line = True 87 break 88 for header in sorted(headerblock, key=IncludeCompareKey): 89 outfile.write(header) 90 if infile_ended_on_include_line: 91 # We already wrote the last line above; exit to ensure it isn't written 92 # again. 93 return 94 # Intentionally fall through, to write the line that caused 95 # the above while loop to exit. 96 outfile.write(line) 97 98 99 def FixFileWithConfirmFunction(filename, confirm_function, 100 perform_safety_checks): 101 """Creates a fixed version of the file, invokes |confirm_function| 102 to decide whether to use the new file, and cleans up. 103 104 |confirm_function| takes two parameters, the original filename and 105 the fixed-up filename, and returns True to use the fixed-up file, 106 false to not use it. 107 108 If |perform_safety_checks| is True, then the function checks whether it is 109 unsafe to reorder headers in this file and skips the reorder with a warning 110 message in that case. 111 """ 112 if perform_safety_checks and IsUnsafeToReorderHeaders(filename): 113 print ('Not reordering headers in %s as the script thinks that the ' 114 'order of headers in this file is semantically significant.' 115 % (filename)) 116 return 117 fixfilename = filename + '.new' 118 infile = open(filename, 'rb') 119 outfile = open(fixfilename, 'wb') 120 SortHeader(infile, outfile) 121 infile.close() 122 outfile.close() # Important so the below diff gets the updated contents. 123 124 try: 125 if confirm_function(filename, fixfilename): 126 if sys.platform == 'win32': 127 os.unlink(filename) 128 os.rename(fixfilename, filename) 129 finally: 130 try: 131 os.remove(fixfilename) 132 except OSError: 133 # If the file isn't there, we don't care. 134 pass 135 136 137 def DiffAndConfirm(filename, should_confirm, perform_safety_checks): 138 """Shows a diff of what the tool would change the file named 139 filename to. Shows a confirmation prompt if should_confirm is true. 140 Saves the resulting file if should_confirm is false or the user 141 answers Y to the confirmation prompt. 142 """ 143 def ConfirmFunction(filename, fixfilename): 144 diff = os.system('diff -u %s %s' % (filename, fixfilename)) 145 if sys.platform != 'win32': 146 diff >>= 8 147 if diff == 0: # Check exit code. 148 print '%s: no change' % filename 149 return False 150 151 return (not should_confirm or YesNo('Use new file (y/N)?')) 152 153 FixFileWithConfirmFunction(filename, ConfirmFunction, perform_safety_checks) 154 155 def IsUnsafeToReorderHeaders(filename): 156 # *_message_generator.cc is almost certainly a file that generates IPC 157 # definitions. Changes in include order in these files can result in them not 158 # building correctly. 159 if filename.find("message_generator.cc") != -1: 160 return True 161 return False 162 163 def main(): 164 parser = optparse.OptionParser(usage='%prog filename1 filename2 ...') 165 parser.add_option('-f', '--force', action='store_false', default=True, 166 dest='should_confirm', 167 help='Turn off confirmation prompt.') 168 parser.add_option('--no_safety_checks', 169 action='store_false', default=True, 170 dest='perform_safety_checks', 171 help='Do not perform the safety checks via which this ' 172 'script refuses to operate on files for which it thinks ' 173 'the include ordering is semantically significant.') 174 opts, filenames = parser.parse_args() 175 176 if len(filenames) < 1: 177 parser.print_help() 178 return 1 179 180 for filename in filenames: 181 DiffAndConfirm(filename, opts.should_confirm, opts.perform_safety_checks) 182 183 184 if __name__ == '__main__': 185 sys.exit(main()) 186