Add tools/checkperms/ from the chromium repo

tools/checkperms/checkperms.py

Index: tools/checkperms/checkperms.py
diff --git a/tools/checkperms/checkperms.py b/tools/checkperms/checkperms.py
new file mode 100755
index 0000000000000000000000000000000000000000..e2807c73c58b394f72f08b714a8840ba022b5132
--- /dev/null
+++ b/tools/checkperms/checkperms.py
@@ -0,0 +1,480 @@
+#!/usr/bin/env python
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Makes sure files have the right permissions.
+
+Some developers have broken SCM configurations that flip the executable
+permission on for no good reason. Unix developers who run ls --color will then
+see .cc files in green and get confused.
+
+- For file extensions that must be executable, add it to EXECUTABLE_EXTENSIONS.
+- For file extensions that must not be executable, add it to
+  NOT_EXECUTABLE_EXTENSIONS.
+- To ignore all the files inside a directory, add it to IGNORED_PATHS.
+- For file base name with ambiguous state and that should not be checked for
+  shebang, add it to IGNORED_FILENAMES.
+
+Any file not matching the above will be opened and looked if it has a shebang
+or an ELF header. If this does not match the executable bit on the file, the
+file will be flagged.
+
+Note that all directory separators must be slashes (Unix-style) and not
+backslashes. All directories should be relative to the source root and all
+file paths should be only lowercase.
+"""
+
+import json
+import logging
+import optparse
+import os
+import stat
+import string
+import subprocess
+import sys
+
+#### USER EDITABLE SECTION STARTS HERE ####
+
+# Files with these extensions must have executable bit set.
+#
+# Case-sensitive.
+EXECUTABLE_EXTENSIONS = (
+  'bat',
+  'dll',
+  'dylib',
+  'exe',
+)
+
+# These files must have executable bit set.
+#
+# Case-insensitive, lower-case only.
+EXECUTABLE_PATHS = (
+  'chrome/test/data/app_shim/app_shim_32_bit.app/contents/'
+      'macos/app_mode_loader',
+  'chrome/test/data/extensions/uitest/plugins/plugin.plugin/contents/'
+      'macos/testnetscapeplugin',
+  'chrome/test/data/extensions/uitest/plugins_private/plugin.plugin/contents/'
+      'macos/testnetscapeplugin',
+)
+
+# These files must not have the executable bit set. This is mainly a performance
+# optimization as these files are not checked for shebang. The list was
+# partially generated from:
+# git ls-files | grep "\\." | sed 's/.*\.//' | sort | uniq -c | sort -b -g
+#
+# Case-sensitive.
+NON_EXECUTABLE_EXTENSIONS = (
+  '1',
+  '3ds',
+  'S',
+  'am',
+  'applescript',
+  'asm',
+  'c',
+  'cc',
+  'cfg',
+  'chromium',
+  'cpp',
+  'crx',
+  'cs',
+  'css',
+  'cur',
+  'def',
+  'der',
+  'expected',
+  'gif',
+  'grd',
+  'gyp',
+  'gypi',
+  'h',
+  'hh',
+  'htm',
+  'html',
+  'hyph',
+  'ico',
+  'idl',
+  'java',
+  'jpg',
+  'js',
+  'json',
+  'm',
+  'm4',
+  'mm',
+  'mms',
+  'mock-http-headers',
+  'nexe',
+  'nmf',
+  'onc',
+  'pat',
+  'patch',
+  'pdf',
+  'pem',
+  'plist',
+  'png',
+  'proto',
+  'rc',
+  'rfx',
+  'rgs',
+  'rules',
+  'spec',
+  'sql',
+  'srpc',
+  'svg',
+  'tcl',
+  'test',
+  'tga',
+  'txt',
+  'vcproj',
+  'vsprops',
+  'webm',
+  'word',
+  'xib',
+  'xml',
+  'xtb',
+  'zip',
+)
+
+# These files must not have executable bit set.
+#
+# Case-insensitive, lower-case only.
+NON_EXECUTABLE_PATHS = (
+  'build/android/tests/symbolize/liba.so',
+  'build/android/tests/symbolize/libb.so',
+  'chrome/installer/mac/sign_app.sh.in',
+  'chrome/installer/mac/sign_versioned_dir.sh.in',
+  'chrome/test/data/extensions/uitest/plugins/plugin32.so',
+  'chrome/test/data/extensions/uitest/plugins/plugin64.so',
+  'chrome/test/data/extensions/uitest/plugins_private/plugin32.so',
+  'chrome/test/data/extensions/uitest/plugins_private/plugin64.so',
+  'components/test/data/component_updater/ihfokbkgjpifnbbojhneepfflplebdkc/'
+      'ihfokbkgjpifnbbojhneepfflplebdkc_1/a_changing_binary_file',
+  'components/test/data/component_updater/ihfokbkgjpifnbbojhneepfflplebdkc/'
+      'ihfokbkgjpifnbbojhneepfflplebdkc_2/a_changing_binary_file',
+  'courgette/testdata/elf-32-1',
+  'courgette/testdata/elf-32-2',
+  'courgette/testdata/elf-64',
+)
+
+# File names that are always whitelisted.  (These are mostly autoconf spew.)
+#
+# Case-sensitive.
+IGNORED_FILENAMES = (
+  'config.guess',
+  'config.sub',
+  'configure',
+  'depcomp',
+  'install-sh',
+  'missing',
+  'mkinstalldirs',
+  'naclsdk',
+  'scons',
+)
+
+# File paths starting with one of these will be ignored as well.
+# Please consider fixing your file permissions, rather than adding to this list.
+#
+# Case-insensitive, lower-case only.
+IGNORED_PATHS = (
+  'native_client_sdk/src/build_tools/sdk_tools/third_party/fancy_urllib/'
+      '__init__.py',
+  'out/',
+  # TODO(maruel): Fix these.
+  'third_party/android_testrunner/',
+  'third_party/bintrees/',
+  'third_party/closure_linter/',
+  'third_party/devscripts/licensecheck.pl.vanilla',
+  'third_party/hyphen/',
+  'third_party/jemalloc/',
+  'third_party/lcov-1.9/contrib/galaxy/conglomerate_functions.pl',
+  'third_party/lcov-1.9/contrib/galaxy/gen_makefile.sh',
+  'third_party/lcov/contrib/galaxy/conglomerate_functions.pl',
+  'third_party/lcov/contrib/galaxy/gen_makefile.sh',
+  'third_party/libevent/autogen.sh',
+  'third_party/libevent/test/test.sh',
+  'third_party/libxml/linux/xml2-config',
+  'third_party/libxml/src/ltmain.sh',
+  'third_party/mesa/',
+  'third_party/protobuf/',
+  'third_party/python_gflags/gflags.py',
+  'third_party/sqlite/',
+  'third_party/talloc/script/mksyms.sh',
+  'third_party/tcmalloc/',
+  'third_party/tlslite/setup.py',
+)
+
+#### USER EDITABLE SECTION ENDS HERE ####
+
+assert set(EXECUTABLE_EXTENSIONS) & set(NON_EXECUTABLE_EXTENSIONS) == set()
+assert set(EXECUTABLE_PATHS) & set(NON_EXECUTABLE_PATHS) == set()
+
+VALID_CHARS = set(string.ascii_lowercase + string.digits + '/-_.')
+for paths in (EXECUTABLE_PATHS, NON_EXECUTABLE_PATHS, IGNORED_PATHS):
+  assert all([set(path).issubset(VALID_CHARS) for path in paths])
+
+
+def capture(cmd, cwd):
+  """Returns the output of a command.
+
+  Ignores the error code or stderr.
+  """
+  logging.debug('%s; cwd=%s' % (' '.join(cmd), cwd))
+  env = os.environ.copy()
+  env['LANGUAGE'] = 'en_US.UTF-8'
+  p = subprocess.Popen(
+      cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=cwd, env=env)
+  return p.communicate()[0]
+
+
+def get_git_root(dir_path):
+  """Returns the git checkout root or None."""
+  root = capture(['git', 'rev-parse', '--show-toplevel'], dir_path).strip()
+  if root:
+    return root
+
+
+def is_ignored(rel_path):
+  """Returns True if rel_path is in our whitelist of files to ignore."""
+  rel_path = rel_path.lower()
+  return (
+      os.path.basename(rel_path) in IGNORED_FILENAMES or
+      rel_path.lower().startswith(IGNORED_PATHS))
+
+
+def must_be_executable(rel_path):
+  """The file name represents a file type that must have the executable bit
+  set.
+  """
+  return (os.path.splitext(rel_path)[1][1:] in EXECUTABLE_EXTENSIONS or
+          rel_path.lower() in EXECUTABLE_PATHS)
+
+
+def must_not_be_executable(rel_path):
+  """The file name represents a file type that must not have the executable
+  bit set.
+  """
+  return (os.path.splitext(rel_path)[1][1:] in NON_EXECUTABLE_EXTENSIONS or
+          rel_path.lower() in NON_EXECUTABLE_PATHS)
+
+
+def has_executable_bit(full_path):
+  """Returns if any executable bit is set."""
+  permission = stat.S_IXUSR | stat.S_IXGRP | stat.S_IXOTH
+  return bool(permission & os.stat(full_path).st_mode)
+
+
+def has_shebang_or_is_elf(full_path):
+  """Returns if the file starts with #!/ or is an ELF binary.
+
+  full_path is the absolute path to the file.
+  """
+  with open(full_path, 'rb') as f:
+    data = f.read(4)
+    return (data[:3] == '#!/' or data == '#! /', data == '\x7fELF')
+
+
+def check_file(root_path, rel_path):
+  """Checks the permissions of the file whose path is root_path + rel_path and
+  returns an error if it is inconsistent. Returns None on success.
+
+  It is assumed that the file is not ignored by is_ignored().
+
+  If the file name is matched with must_be_executable() or
+  must_not_be_executable(), only its executable bit is checked.
+  Otherwise, the first few bytes of the file are read to verify if it has a
+  shebang or ELF header and compares this with the executable bit on the file.
+  """
+  full_path = os.path.join(root_path, rel_path)
+  def result_dict(error):
+    return {
+      'error': error,
+      'full_path': full_path,
+      'rel_path': rel_path,
+    }
+  try:
+    bit = has_executable_bit(full_path)
+  except OSError:
+    # It's faster to catch exception than call os.path.islink(). Chromium
+    # tree happens to have invalid symlinks under
+    # third_party/openssl/openssl/test/.
+    return None
+
+  if must_be_executable(rel_path):
+    if not bit:
+      return result_dict('Must have executable bit set')
+    return
+  if must_not_be_executable(rel_path):
+    if bit:
+      return result_dict('Must not have executable bit set')
+    return
+
+  # For the others, it depends on the file header.
+  (shebang, elf) = has_shebang_or_is_elf(full_path)
+  if bit != (shebang or elf):
+    if bit:
+      return result_dict('Has executable bit but not shebang or ELF header')
+    if shebang:
+      return result_dict('Has shebang but not executable bit')
+    return result_dict('Has ELF header but not executable bit')
+
+
+def check_files(root, files):
+  gen = (check_file(root, f) for f in files if not is_ignored(f))
+  return filter(None, gen)
+
+
+class ApiBase(object):
+  def __init__(self, root_dir, bare_output):
+    self.root_dir = root_dir
+    self.bare_output = bare_output
+    self.count = 0
+    self.count_read_header = 0
+
+  def check_file(self, rel_path):
+    logging.debug('check_file(%s)' % rel_path)
+    self.count += 1
+
+    if (not must_be_executable(rel_path) and
+        not must_not_be_executable(rel_path)):
+      self.count_read_header += 1
+
+    return check_file(self.root_dir, rel_path)
+
+  def check_dir(self, rel_path):
+    return self.check(rel_path)
+
+  def check(self, start_dir):
+    """Check the files in start_dir, recursively check its subdirectories."""
+    errors = []
+    items = self.list_dir(start_dir)
+    logging.info('check(%s) -> %d' % (start_dir, len(items)))
+    for item in items:
+      full_path = os.path.join(self.root_dir, start_dir, item)
+      rel_path = full_path[len(self.root_dir) + 1:]
+      if is_ignored(rel_path):
+        continue
+      if os.path.isdir(full_path):
+        # Depth first.
+        errors.extend(self.check_dir(rel_path))
+      else:
+        error = self.check_file(rel_path)
+        if error:
+          errors.append(error)
+    return errors
+
+  def list_dir(self, start_dir):
+    """Lists all the files and directory inside start_dir."""
+    return sorted(
+      x for x in os.listdir(os.path.join(self.root_dir, start_dir))
+      if not x.startswith('.')
+    )
+
+
+class ApiAllFilesAtOnceBase(ApiBase):
+  _files = None
+
+  def list_dir(self, start_dir):
+    """Lists all the files and directory inside start_dir."""
+    if self._files is None:
+      self._files = sorted(self._get_all_files())
+      if not self.bare_output:
+        print 'Found %s files' % len(self._files)
+    start_dir = start_dir[len(self.root_dir) + 1:]
+    return [
+      x[len(start_dir):] for x in self._files if x.startswith(start_dir)
+    ]
+
+  def _get_all_files(self):
+    """Lists all the files and directory inside self._root_dir."""
+    raise NotImplementedError()
+
+
+class ApiGit(ApiAllFilesAtOnceBase):
+  def _get_all_files(self):
+    return capture(['git', 'ls-files'], cwd=self.root_dir).splitlines()
+
+
+def get_scm(dir_path, bare):
+  """Returns a properly configured ApiBase instance."""
+  cwd = os.getcwd()
+  root = get_git_root(dir_path or cwd)
+  if root:
+    if not bare:
+      print('Found git repository at %s' % root)
+    return ApiGit(dir_path or root, bare)
+
+  # Returns a non-scm aware checker.
+  if not bare:
+    print('Failed to determine the SCM for %s' % dir_path)
+  return ApiBase(dir_path or cwd, bare)
+
+
+def main():
+  usage = """Usage: python %prog [--root <root>] [tocheck]
+  tocheck  Specifies the directory, relative to root, to check. This defaults
+           to "." so it checks everything.
+
+Examples:
+  python %prog
+  python %prog --root /path/to/source chrome"""
+
+  parser = optparse.OptionParser(usage=usage)
+  parser.add_option(
+      '--root',
+      help='Specifies the repository root. This defaults '
+           'to the checkout repository root')
+  parser.add_option(
+      '-v', '--verbose', action='count', default=0, help='Print debug logging')
+  parser.add_option(
+      '--bare',
+      action='store_true',
+      default=False,
+      help='Prints the bare filename triggering the checks')
+  parser.add_option(
+      '--file', action='append', dest='files',
+      help='Specifics a list of files to check the permissions of. Only these '
+      'files will be checked')
+  parser.add_option('--json', help='Path to JSON output file')
+  options, args = parser.parse_args()
+
+  levels = [logging.ERROR, logging.INFO, logging.DEBUG]
+  logging.basicConfig(level=levels[min(len(levels) - 1, options.verbose)])
+
+  if len(args) > 1:
+    parser.error('Too many arguments used')
+
+  if options.root:
+    options.root = os.path.abspath(options.root)
+
+  if options.files:
+    # --file implies --bare (for PRESUBMIT.py).
+    options.bare = True
+
+    errors = check_files(options.root, options.files)
+  else:
+    api = get_scm(options.root, options.bare)
+    start_dir = args[0] if args else api.root_dir
+    errors = api.check(start_dir)
+
+    if not options.bare:
+      print('Processed %s files, %d files where tested for shebang/ELF '
+            'header' % (api.count, api.count_read_header))
+
+  if options.json:
+    with open(options.json, 'w') as f:
+      json.dump(errors, f)
+
+  if errors:
+    if options.bare:
+      print '\n'.join(e['full_path'] for e in errors)
+    else:
+      print '\nFAILED\n'
+      print '\n'.join('%s: %s' % (e['full_path'], e['error']) for e in errors)
+    return 1
+  if not options.bare:
+    print '\nSUCCESS\n'
+  return 0
+
+
+if '__main__' == __name__:
+  sys.exit(main())