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.
7 lastchange.py -- Chromium revision fetching utility.
16 _GIT_SVN_ID_REGEX = re.compile(r'.*git-svn-id:\s*([^@]*)@([0-9]+)', re.DOTALL)
18 class VersionInfo(object):
19 def __init__(self, url, revision):
21 self.revision = revision
24 def FetchSVNRevision(directory, svn_url_regex):
26 Fetch the Subversion branch and revision for a given directory.
31 A VersionInfo object or None on error.
34 proc = subprocess.Popen(['svn', 'info'],
35 stdout=subprocess.PIPE,
36 stderr=subprocess.PIPE,
38 shell=(sys.platform=='win32'))
40 # command is apparently either not installed or not executable.
46 for line in proc.stdout:
50 key, val = line.split(': ', 1)
54 match = svn_url_regex.search(attrs['URL'])
59 revision = attrs['Revision']
63 return VersionInfo(url, revision)
66 def RunGitCommand(directory, command):
68 Launches git subcommand.
73 A process object or None.
75 command = ['git'] + command
76 # Force shell usage under cygwin. This is a workaround for
77 # mysterious loss of cwd while invoking cygwin's git.
78 # We can't just pass shell=True to Popen, as under win32 this will
79 # cause CMD to be used, while we explicitly want a cygwin shell.
80 if sys.platform == 'cygwin':
81 command = ['sh', '-c', ' '.join(command)]
83 proc = subprocess.Popen(command,
84 stdout=subprocess.PIPE,
85 stderr=subprocess.PIPE,
87 shell=(sys.platform=='win32'))
93 def FetchGitRevision(directory):
95 Fetch the Git hash for a given directory.
100 A VersionInfo object or None on error.
102 proc = RunGitCommand(directory, ['rev-parse', 'HEAD'])
104 output = proc.communicate()[0].strip()
105 if proc.returncode == 0 and output:
106 return VersionInfo('git', output[:7])
110 def FetchGitSVNURLAndRevision(directory, svn_url_regex):
112 Fetch the Subversion URL and revision through Git.
114 Errors are swallowed.
117 A tuple containing the Subversion URL and revision.
119 proc = RunGitCommand(directory, ['log', '-1',
120 '--grep=git-svn-id', '--format=%b'])
122 output = proc.communicate()[0].strip()
123 if proc.returncode == 0 and output:
124 # Extract the latest SVN revision and the SVN URL.
125 # The target line is the last "git-svn-id: ..." line like this:
126 # git-svn-id: svn://svn.chromium.org/chrome/trunk/src@85528 0039d316....
127 match = _GIT_SVN_ID_REGEX.search(output)
129 revision = match.group(2)
130 url_match = svn_url_regex.search(match.group(1))
132 url = url_match.group(2)
139 def FetchGitSVNRevision(directory, svn_url_regex):
141 Fetch the Git-SVN identifier for the local tree.
143 Errors are swallowed.
145 url, revision = FetchGitSVNURLAndRevision(directory, svn_url_regex)
147 return VersionInfo(url, revision)
151 def FetchVersionInfo(default_lastchange, directory=None,
152 directory_regex_prior_to_src_url='chrome|blink|svn'):
154 Returns the last change (in the form of a branch, revision tuple),
155 from some appropriate revision control system.
157 svn_url_regex = re.compile(
158 r'.*/(' + directory_regex_prior_to_src_url + r')(/.*)')
160 version_info = (FetchSVNRevision(directory, svn_url_regex) or
161 FetchGitSVNRevision(directory, svn_url_regex) or
162 FetchGitRevision(directory))
164 if default_lastchange and os.path.exists(default_lastchange):
165 revision = open(default_lastchange, 'r').read().strip()
166 version_info = VersionInfo(None, revision)
168 version_info = VersionInfo(None, None)
172 def WriteIfChanged(file_name, contents):
174 Writes the specified contents to the specified file_name
175 iff the contents are different than the current contents.
178 old_contents = open(file_name, 'r').read()
179 except EnvironmentError:
182 if contents == old_contents:
185 open(file_name, 'w').write(contents)
192 parser = optparse.OptionParser(usage="lastchange.py [options]")
193 parser.add_option("-d", "--default-lastchange", metavar="FILE",
194 help="default last change input FILE")
195 parser.add_option("-o", "--output", metavar="FILE",
196 help="write last change to FILE")
197 parser.add_option("--revision-only", action='store_true',
198 help="just print the SVN revision number")
199 parser.add_option("-s", "--source-dir", metavar="DIR",
200 help="use repository in the given directory")
201 opts, args = parser.parse_args(argv[1:])
203 out_file = opts.output
205 while len(args) and out_file is None:
207 out_file = args.pop(0)
209 sys.stderr.write('Unexpected arguments: %r\n\n' % args)
214 src_dir = opts.source_dir
216 src_dir = os.path.dirname(os.path.abspath(__file__))
218 version_info = FetchVersionInfo(opts.default_lastchange, src_dir)
220 if version_info.revision == None:
221 version_info.revision = '0'
223 if opts.revision_only:
224 print version_info.revision
226 contents = "LASTCHANGE=%s\n" % version_info.revision
228 WriteIfChanged(out_file, contents)
230 sys.stdout.write(contents)
235 if __name__ == '__main__':