merge_common.py revision 1877218f76a9fd423566d653593083bc9ea8fd13 
1# Copyright (C) 2012 The Android Open Source Project
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#      http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15"""Common data/functions for the Chromium merging scripts."""
16
17import logging
18import os
19import re
20import subprocess
21
22
23REPOSITORY_ROOT = os.path.join(os.environ['ANDROID_BUILD_TOP'],
24                               'external/chromium_org')
25
26
27# Whitelist of projects that need to be merged to build WebView. We don't need
28# the other upstream repositories used to build the actual Chrome app.
29# Different stages of the merge process need different ways of looking at the
30# list, so we construct different combinations below.
31
32THIRD_PARTY_PROJECTS_WITH_FLAT_HISTORY = [
33    'third_party/WebKit',
34]
35
36THIRD_PARTY_PROJECTS_WITH_FULL_HISTORY = [
37    'sdch/open-vcdiff',
38    'testing/gtest',
39    'third_party/angle_dx11',
40    'third_party/eyesfree/src/android/java/src/com/googlecode/eyesfree/braille',
41    'third_party/freetype',
42    'third_party/icu',
43    'third_party/leveldatabase/src',
44    'third_party/libjingle/source/talk',
45    'third_party/libphonenumber/src/phonenumbers',
46    'third_party/libphonenumber/src/resources',
47    'third_party/mesa/src',
48    'third_party/openssl',
49    'third_party/opus/src',
50    'third_party/ots',
51    'third_party/skia/include',
52    'third_party/skia/gyp',
53    'third_party/skia/src',
54    'third_party/smhasher/src',
55    'third_party/yasm/source/patched-yasm',
56    'tools/grit',
57    'tools/gyp',
58    'v8',
59]
60
61PROJECTS_WITH_FLAT_HISTORY = ['.'] + THIRD_PARTY_PROJECTS_WITH_FLAT_HISTORY
62PROJECTS_WITH_FULL_HISTORY = THIRD_PARTY_PROJECTS_WITH_FULL_HISTORY
63
64THIRD_PARTY_PROJECTS = (THIRD_PARTY_PROJECTS_WITH_FLAT_HISTORY +
65                        THIRD_PARTY_PROJECTS_WITH_FULL_HISTORY)
66
67ALL_PROJECTS = ['.'] + THIRD_PARTY_PROJECTS
68
69
70# Directories to be removed when flattening history.
71PRUNE_WHEN_FLATTENING = {
72    'third_party/WebKit': [
73        'LayoutTests',
74    ],
75}
76
77
78# Only projects that have their history flattened can have directories pruned.
79assert all(p in PROJECTS_WITH_FLAT_HISTORY for p in PRUNE_WHEN_FLATTENING)
80
81
82class MergeError(Exception):
83  """Used to signal an error that prevents the merge from being completed."""
84
85
86class CommandError(MergeError):
87  """This exception is raised when a process run by GetCommandStdout fails."""
88
89  def __init__(self, returncode, cmd, cwd, stdout, stderr):
90    super(CommandError, self).__init__()
91    self.returncode = returncode
92    self.cmd = cmd
93    self.cwd = cwd
94    self.stdout = stdout
95    self.stderr = stderr
96
97  def __str__(self):
98    return ("Command '%s' returned non-zero exit status %d. cwd was '%s'.\n\n"
99            "===STDOUT===\n%s\n===STDERR===\n%s\n" %
100            (self.cmd, self.returncode, self.cwd, self.stdout, self.stderr))
101
102
103class TemporaryMergeError(MergeError):
104  """A merge error that can potentially be resolved by trying again later."""
105
106
107def GetCommandStdout(args, cwd=REPOSITORY_ROOT, ignore_errors=False):
108  """Gets stdout from runnng the specified shell command.
109
110  Similar to subprocess.check_output() except that it can capture stdout and
111  stderr separately for better error reporting.
112
113  Args:
114    args: The command and its arguments as an iterable.
115    cwd: The working directory to use. Defaults to REPOSITORY_ROOT.
116    ignore_errors: Ignore the command's return code and stderr.
117  Returns:
118    stdout from running the command.
119  Raises:
120    CommandError: if the command exited with a nonzero status.
121  """
122  p = subprocess.Popen(args=args, cwd=cwd, stdout=subprocess.PIPE,
123                       stderr=subprocess.PIPE)
124  stdout, stderr = p.communicate()
125  if p.returncode == 0 or ignore_errors:
126    return stdout
127  else:
128    raise CommandError(p.returncode, ' '.join(args), cwd, stdout, stderr)
129
130
131def CheckNoConflictsAndCommitMerge(commit_message, unattended=False,
132                                   cwd=REPOSITORY_ROOT):
133  """Checks for conflicts and commits once they are resolved.
134
135  Certain conflicts are resolved automatically; if any remain, the user is
136  prompted to resolve them. The user can specify a custom commit message.
137
138  Args:
139    commit_message: The default commit message.
140    unattended: If running unattended, abort on conflicts.
141    cwd: Working directory to use.
142  Raises:
143    TemporaryMergeError: If there are conflicts in unattended mode.
144  """
145  status = GetCommandStdout(['git', 'status', '--porcelain'], cwd=cwd)
146  conflicts_deleted_by_us = re.findall(r'^(?:DD|DU) ([^\n]+)$', status,
147                                       flags=re.MULTILINE)
148  if conflicts_deleted_by_us:
149    logging.info('Keeping ours for the following locally deleted files.\n  %s',
150                 '\n  '.join(conflicts_deleted_by_us))
151    GetCommandStdout(['git', 'rm', '-rf', '--ignore-unmatch'] +
152                     conflicts_deleted_by_us, cwd=cwd)
153
154  # If upstream renames a file we have deleted then it will conflict, but
155  # we shouldn't just blindly delete these files as they may have been renamed
156  # into a directory we don't delete. Let them get re-added; they will get
157  # re-deleted if they are still in a directory we delete.
158  conflicts_renamed_by_them = re.findall(r'^UA ([^\n]+)$', status,
159                                         flags=re.MULTILINE)
160  if conflicts_renamed_by_them:
161    logging.info('Adding theirs for the following locally deleted files.\n %s',
162                 '\n  '.join(conflicts_renamed_by_them))
163    GetCommandStdout(['git', 'add', '-f'] + conflicts_renamed_by_them, cwd=cwd)
164
165  while True:
166    status = GetCommandStdout(['git', 'status', '--porcelain'], cwd=cwd)
167    conflicts = re.findall(r'^((DD|AU|UD|UA|DU|AA|UU) [^\n]+)$', status,
168                           flags=re.MULTILINE)
169    if not conflicts:
170      break
171    if unattended:
172      GetCommandStdout(['git', 'reset', '--hard'], cwd=cwd)
173      raise TemporaryMergeError('Cannot resolve merge conflicts.')
174    conflicts_string = '\n'.join([x[0] for x in conflicts])
175    new_commit_message = raw_input(
176        ('The following conflicts exist and must be resolved.\n\n%s\n\nWhen '
177         'done, enter a commit message or press enter to use the default '
178         '(\'%s\').\n\n') % (conflicts_string, commit_message))
179    if new_commit_message:
180      commit_message = new_commit_message
181
182  GetCommandStdout(['git', 'commit', '-m', commit_message], cwd=cwd)
183