Add DEPS roll script for SwiftShader.

tools/roll_swiftshader.py

Index: tools/roll_swiftshader.py
diff --git a/tools/roll_swiftshader.py b/tools/roll_swiftshader.py
new file mode 100755
index 0000000000000000000000000000000000000000..d24a43a7b3e33497984807f94ecce11fd07c4209
--- /dev/null
+++ b/tools/roll_swiftshader.py
@@ -0,0 +1,421 @@
+#!/usr/bin/env python
+# Copyright 2015 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.
+
+import argparse
+import collections
+import logging
+import os
+import re
+import subprocess
+import sys
+import time
+
+extra_cq_trybots = [
+  {
+    "mastername": "master.tryserver.chromium.win",
+    "buildernames": ["win_optional_gpu_tests_rel"]
+  },
+  {
+    "mastername": "master.tryserver.chromium.mac",
+    "buildernames": ["mac_optional_gpu_tests_rel"]
+  },
+  {
+    "mastername": "master.tryserver.chromium.linux",
+    "buildernames": ["linux_optional_gpu_tests_rel"]
+  },
+  {
+    "mastername": "master.tryserver.chromium.android",
+    "buildernames": ["android_optional_gpu_tests_rel"]
+  }
+]
+extra_fyi_trybots = [
+  {
+    "mastername": "master.tryserver.chromium.win",
+    "buildernames": ["win_clang_dbg"]
+  }
+]
+
+SCRIPT_DIR = os.path.dirname(os.path.realpath(__file__))
+SRC_DIR = os.path.abspath(os.path.join(SCRIPT_DIR, os.pardir))
+sys.path.insert(0, os.path.join(SRC_DIR, 'build'))
+import find_depot_tools
+find_depot_tools.add_depot_tools_to_path()
+import roll_dep_svn
+from gclient import GClientKeywords
+from third_party import upload
+
+# Avoid depot_tools/third_party/upload.py print verbose messages.
+upload.verbosity = 0  # Errors only.
+
+CHROMIUM_GIT_URL = 'https://chromium.googlesource.com/chromium/src.git'
+CL_ISSUE_RE = re.compile('^Issue number: ([0-9]+) \((.*)\)$')
+RIETVELD_URL_RE = re.compile('^https?://(.*)/(.*)')
+ROLL_BRANCH_NAME = 'special_swiftshader_roll_branch'
+TRYJOB_STATUS_SLEEP_SECONDS = 30
+
+# Use a shell for subcommands on Windows to get a PATH search.
+IS_WIN = sys.platform.startswith('win')
+SWIFTSHADER_PATH = os.path.join('third_party', 'swiftshader')
+
+CommitInfo = collections.namedtuple('CommitInfo', ['git_commit',
+                                                   'git_repo_url'])
+CLInfo = collections.namedtuple('CLInfo', ['issue', 'url', 'rietveld_server'])
+
+def _PosixPath(path):
+  """Convert a possibly-Windows path to a posix-style path."""
+  (_, path) = os.path.splitdrive(path)
+  return path.replace(os.sep, '/')
+
+def _ParseGitCommitHash(description):
+  for line in description.splitlines():
+    if line.startswith('commit '):
+      return line.split()[1]
+  logging.error('Failed to parse git commit id from:\n%s\n', description)
+  sys.exit(-1)
+  return None
+
+
+def _ParseDepsFile(filename):
+  with open(filename, 'rb') as f:
+    deps_content = f.read()
+  return _ParseDepsDict(deps_content)
+
+
+def _ParseDepsDict(deps_content):
+  local_scope = {}
+  var = GClientKeywords.VarImpl({}, local_scope)
+  global_scope = {
+    'From': GClientKeywords.FromImpl,
+    'Var': var.Lookup,
+    'deps_os': {},
+  }
+  exec(deps_content, global_scope, local_scope)
+  return local_scope
+
+
+def _GenerateCLDescriptionCommand(swiftshader_current, swiftshader_new, bugs,
+                                  tbr):
+  def GetChangeString(current_hash, new_hash):
+    return '%s..%s' % (current_hash[0:7], new_hash[0:7]);
+
+  def GetChangeLogURL(git_repo_url, change_string):
+    return '%s/+log/%s' % (git_repo_url, change_string)
+
+  def GetBugString(bugs):
+    bug_str = 'BUG='
+    for bug in bugs:
+      bug_str += bug + ','
+    return bug_str.rstrip(',')
+
+  if swiftshader_current.git_commit != swiftshader_new.git_commit:
+    change_str = GetChangeString(swiftshader_current.git_commit,
+                                 swiftshader_new.git_commit)
+    changelog_url = GetChangeLogURL(swiftshader_current.git_repo_url,
+                                    change_str)
+
+  def GetExtraCQTrybotString():
+    s = ''
+    for t in extra_cq_trybots:
+      if s:
+        s += ';'
+      s += t['mastername'] + ':' + ','.join(t['buildernames'])
+    return s
+
+  def GetTBRString(tbr):
+    if not tbr:
+      return ''
+    return 'TBR=' + tbr
+
+  extra_trybot_args = []
+  if extra_cq_trybots:
+    extra_trybot_string = GetExtraCQTrybotString()
+    extra_trybot_args = ['-m', 'CQ_INCLUDE_TRYBOTS=' + extra_trybot_string]
+
+  return [
+    '-m', 'Roll SwiftShader ' + change_str,
+    '-m', '%s' % changelog_url,
+    '-m', GetBugString(bugs),
+    '-m', GetTBRString(tbr),
+    '-m', 'TEST=bots',
+  ] + extra_trybot_args
+
+
+class AutoRoller(object):
+  def __init__(self, chromium_src):
+    self._chromium_src = chromium_src
+
+  def _RunCommand(self, command, working_dir=None, ignore_exit_code=False,
+                  extra_env=None):
+    """Runs a command and returns the stdout from that command.
+
+    If the command fails (exit code != 0), the function will exit the process.
+    """
+    working_dir = working_dir or self._chromium_src
+    logging.debug('cmd: %s cwd: %s', ' '.join(command), working_dir)
+    env = os.environ.copy()
+    if extra_env:
+      logging.debug('extra env: %s', extra_env)
+      env.update(extra_env)
+    p = subprocess.Popen(command, stdout=subprocess.PIPE,
+                         stderr=subprocess.PIPE, shell=IS_WIN, env=env,
+                         cwd=working_dir, universal_newlines=True)
+    output = p.stdout.read()
+    p.wait()
+    p.stdout.close()
+    p.stderr.close()
+
+    if not ignore_exit_code and p.returncode != 0:
+      logging.error('Command failed: %s\n%s', str(command), output)
+      sys.exit(p.returncode)
+    return output
+
+  def _GetCommitInfo(self, path_below_src, git_hash=None, git_repo_url=None):
+    working_dir = os.path.join(self._chromium_src, path_below_src)
+    self._RunCommand(['git', 'fetch', 'origin'], working_dir=working_dir)
+    revision_range = git_hash or 'origin'
+    ret = self._RunCommand(
+        ['git', '--no-pager', 'log', revision_range,
+         '--no-abbrev-commit', '--pretty=full', '-1'],
+        working_dir=working_dir)
+    return CommitInfo(_ParseGitCommitHash(ret), git_repo_url)
+
+  def _GetDepsCommitInfo(self, deps_dict, path_below_src):
+    entry = deps_dict['deps'][_PosixPath('src/%s' % path_below_src)]
+    at_index = entry.find('@')
+    git_repo_url = entry[:at_index]
+    git_hash = entry[at_index + 1:]
+    return self._GetCommitInfo(path_below_src, git_hash, git_repo_url)
+
+  def _GetCLInfo(self):
+    cl_output = self._RunCommand(['git', 'cl', 'issue'])
+    m = CL_ISSUE_RE.match(cl_output.strip())
+    if not m:
+      logging.error('Cannot find any CL info. Output was:\n%s', cl_output)
+      sys.exit(-1)
+    issue_number = int(m.group(1))
+    url = m.group(2)
+
+    # Parse the Rietveld host from the URL.
+    m = RIETVELD_URL_RE.match(url)
+    if not m:
+      logging.error('Cannot parse Rietveld host from URL: %s', url)
+      sys.exit(-1)
+    rietveld_server = m.group(1)
+    return CLInfo(issue_number, url, rietveld_server)
+
+  def _GetCurrentBranchName(self):
+    return self._RunCommand(
+        ['git', 'rev-parse', '--abbrev-ref', 'HEAD']).splitlines()[0]
+
+  def _IsTreeClean(self):
+    lines = self._RunCommand(
+      ['git', 'status', '--porcelain', '-uno']).splitlines()
+    if len(lines) == 0:
+      return True
+
+    logging.debug('Dirty/unversioned files:\n%s', '\n'.join(lines))
+    return False
+
+  def _GetBugList(self, path_below_src, swiftshader_current, swiftshader_new):
+    working_dir = os.path.join(self._chromium_src, path_below_src)
+    lines = self._RunCommand(
+        ['git','log',
+            '%s..%s' % (swiftshader_current.git_commit,
+                        swiftshader_new.git_commit)],
+        working_dir=working_dir).split('\n')
+    ignored_projects = set(['swiftshader'])
+    bugs = set()
+    for line in lines:
+      line = line.strip()
+      bug_prefix = 'BUG='
+      if line.startswith(bug_prefix):
+        bugs_strings = line[len(bug_prefix):].split(',')
+        for bug_string in bugs_strings:
+          ignore_bug = False
+          for ignored_project in ignored_projects:
+            if bug_string.startswith(ignored_project + ':'):
+              ignore_bug = True
+              break
+          if not ignore_bug:
+            bugs.add(bug_string)
+    return bugs
+
+  def _UpdateReadmeFile(self, readme_path, new_revision):
+    readme = open(os.path.join(self._chromium_src, readme_path), 'r+')
+    txt = readme.read()
+    m = re.sub(re.compile('.*^Revision\: ([0-9]*).*', re.MULTILINE),
+        ('Revision: %s' % new_revision), txt)
+    readme.seek(0)
+    readme.write(m)
+    readme.truncate()
+
+  def _TriggerExtraTrybots(self, trybots):
+    for trybot in trybots:
+      for builder in trybot['buildernames']:
+        self._RunCommand([
+            'git', 'cl', 'try',
+            '-m', trybot['mastername'],
+            '-b', builder])
+
+  def PrepareRoll(self, ignore_checks, tbr, should_commit):
+    # TODO(kjellander): use os.path.normcase, os.path.join etc for all paths for
+    # cross platform compatibility.
+
+    if not ignore_checks:
+      if self._GetCurrentBranchName() != 'master':
+        logging.error('Please checkout the master branch.')
+        return -1
+      if not self._IsTreeClean():
+        logging.error('Please make sure you don\'t have any modified files.')
+        return -1
+
+    # Always clean up any previous roll.
+    self.Abort()
+
+    logging.debug('Pulling latest changes')
+    if not ignore_checks:
+      self._RunCommand(['git', 'pull'])
+
+    self._RunCommand(['git', 'checkout', '-b', ROLL_BRANCH_NAME])
+
+    # Modify Chromium's DEPS file.
+
+    # Parse current hashes.
+    deps_filename = os.path.join(self._chromium_src, 'DEPS')
+    deps = _ParseDepsFile(deps_filename)
+    swiftshader_current = self._GetDepsCommitInfo(deps, SWIFTSHADER_PATH)
+
+    # Find ToT revisions.
+    swiftshader_latest = self._GetCommitInfo(SWIFTSHADER_PATH)
+
+    if IS_WIN:
+      # Make sure the roll script doesn't use windows line endings
+      self._RunCommand(['git', 'config', 'core.autocrlf', 'true'])
+
+    self._UpdateDep(deps_filename, SWIFTSHADER_PATH, swiftshader_latest)
+
+    if self._IsTreeClean():
+      logging.debug('Tree is clean - no changes detected.')
+      self._DeleteRollBranch()
+    else:
+      bugs = self._GetBugList(SWIFTSHADER_PATH, swiftshader_current,
+                              swiftshader_latest)
+      description = _GenerateCLDescriptionCommand(
+          swiftshader_current, swiftshader_latest, bugs, tbr)
+      logging.debug('Committing changes locally.')
+      self._RunCommand(['git', 'add', '--update', '.'])
+      self._RunCommand(['git', 'commit'] + description)
+      logging.debug('Uploading changes...')
+      self._RunCommand(['git', 'cl', 'upload'],
+                       extra_env={'EDITOR': 'true'})
+
+      # Kick off tryjobs.
+      base_try_cmd = ['git', 'cl', 'try']
+      self._RunCommand(base_try_cmd)
+
+      if extra_cq_trybots:
+        # Run additional tryjobs.
+        # TODO(kbr): this should not be necessary -- the
+        # CQ_INCLUDE_TRYBOTS directive above should handle it.
+        # http://crbug.com/585237
+        self._TriggerExtraTrybots(extra_cq_trybots)
+
+      if extra_fyi_trybots:
+        self._TriggerExtraTrybots(extra_fyi_trybots)
+
+      # Mark the CL to be committed if requested
+      if should_commit:
+        self._RunCommand(['git', 'cl', 'set-commit'])
+
+      cl_info = self._GetCLInfo()
+      print 'Issue: %d URL: %s' % (cl_info.issue, cl_info.url)
+
+    # Checkout master again.
+    self._RunCommand(['git', 'checkout', 'master'])
+    print 'Roll branch left as ' + ROLL_BRANCH_NAME
+    return 0
+
+  def _UpdateDep(self, deps_filename, dep_relative_to_src, commit_info):
+    dep_name = _PosixPath(os.path.join('src', dep_relative_to_src))
+
+    # roll_dep_svn.py relies on cwd being the Chromium checkout, so let's
+    # temporarily change the working directory and then change back.
+    cwd = os.getcwd()
+    os.chdir(os.path.dirname(deps_filename))
+    roll_dep_svn.update_deps(deps_filename, dep_relative_to_src, dep_name,
+                             commit_info.git_commit, '')
+    os.chdir(cwd)
+
+  def _DeleteRollBranch(self):
+    self._RunCommand(['git', 'checkout', 'master'])
+    self._RunCommand(['git', 'branch', '-D', ROLL_BRANCH_NAME])
+    logging.debug('Deleted the local roll branch (%s)', ROLL_BRANCH_NAME)
+
+
+  def _GetBranches(self):
+    """Returns a tuple of active,branches.
+
+    The 'active' is the name of the currently active branch and 'branches' is a
+    list of all branches.
+    """
+    lines = self._RunCommand(['git', 'branch']).split('\n')
+    branches = []
+    active = ''
+    for l in lines:
+      if '*' in l:
+        # The assumption is that the first char will always be the '*'.
+        active = l[1:].strip()
+        branches.append(active)
+      else:
+        b = l.strip()
+        if b:
+          branches.append(b)
+    return (active, branches)
+
+  def Abort(self):
+    active_branch, branches = self._GetBranches()
+    if active_branch == ROLL_BRANCH_NAME:
+      active_branch = 'master'
+    if ROLL_BRANCH_NAME in branches:
+      print 'Aborting pending roll.'
+      self._RunCommand(['git', 'checkout', ROLL_BRANCH_NAME])
+      # Ignore an error here in case an issue wasn't created for some reason.
+      self._RunCommand(['git', 'cl', 'set_close'], ignore_exit_code=True)
+      self._RunCommand(['git', 'checkout', active_branch])
+      self._RunCommand(['git', 'branch', '-D', ROLL_BRANCH_NAME])
+    return 0
+
+
+def main():
+  parser = argparse.ArgumentParser(
+      description='Auto-generates a CL containing a SwiftShader roll.')
+  parser.add_argument('--abort',
+    help=('Aborts a previously prepared roll. '
+          'Closes any associated issues and deletes the roll branches'),
+    action='store_true')
+  parser.add_argument('--ignore-checks', action='store_true', default=False,
+      help=('Skips checks for being on the master branch, dirty workspaces and '
+            'the updating of the checkout. Will still delete and create local '
+            'Git branches.'))
+  parser.add_argument('--tbr', help='Add a TBR to the commit message.')
+  parser.add_argument('--commit', action='store_true', default=False,
+      help='Submit the roll to the CQ after uploading.')
+  parser.add_argument('-v', '--verbose', action='store_true', default=False,
+      help='Be extra verbose in printing of log messages.')
+  args = parser.parse_args()
+
+  if args.verbose:
+    logging.basicConfig(level=logging.DEBUG)
+  else:
+    logging.basicConfig(level=logging.ERROR)
+
+  autoroller = AutoRoller(SRC_DIR)
+  if args.abort:
+    return autoroller.Abort()
+  else:
+    return autoroller.PrepareRoll(args.ignore_checks, args.tbr, args.commit)
+
+if __name__ == '__main__':
+  sys.exit(main())