[swarming] Port updated version of isolate_driver.py

tools/isolate_driver.py

 #!/usr/bin/env python
 # Copyright 2015 the V8 project authors. All rights reserved.
+# Copyright 2014 The Chromium Authors. All rights reserved.

[Michael Achenbach, 2016/07/06 14:12:40]

This is a 1:1 copy of
https://cs.chromium.org/chromium/src/tools/isolate_driver.py with only the
copyright header adjusted.

 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Adaptor script called through build/isolate.gypi.
 
-Slimmed down version of chromium's isolate driver that doesn't process dynamic
-dependencies.
+Creates a wrapping .isolate which 'includes' the original one, that can be
+consumed by tools/swarming_client/isolate.py. Path variables are determined
+based on the current working directory. The relative_cwd in the .isolated file
+is determined based on the .isolate file that declare the 'command' variable to
+be used so the wrapping .isolate doesn't affect this value.
+
+This script loads build.ninja and processes it to determine all the executables
+referenced by the isolated target. It adds them in the wrapping .isolate file.
+
+WARNING: The target to use for build.ninja analysis is the base name of the
+.isolate file plus '_run'. For example, 'foo_test.isolate' would have the target
+'foo_test_run' analysed.
 """
 
+import errno
+import glob
 import json
 import logging
 import os
+import posixpath
+import StringIO
 import subprocess
 import sys
+import time
 
 TOOLS_DIR = os.path.dirname(os.path.abspath(__file__))
+SWARMING_CLIENT_DIR = os.path.join(TOOLS_DIR, 'swarming_client')
+SRC_DIR = os.path.dirname(TOOLS_DIR)
+
+sys.path.insert(0, SWARMING_CLIENT_DIR)
+
+import isolate_format
+
+
+def load_ninja_recursively(build_dir, ninja_path, build_steps):
+  """Crudely extracts all the subninja and build referenced in ninja_path.
+
+  In particular, it ignores rule and variable declarations. The goal is to be
+  performant (well, as much as python can be performant) which is currently in
+  the <200ms range for a complete chromium tree. As such the code is laid out
+  for performance instead of readability.
+  """
+  logging.debug('Loading %s', ninja_path)
+  try:
+    with open(os.path.join(build_dir, ninja_path), 'rb') as f:
+      line = None
+      merge_line = ''
+      subninja = []
+      for line in f:
+        line = line.rstrip()
+        if not line:
+          continue
+
+        if line[-1] == '$':
+          # The next line needs to be merged in.
+          merge_line += line[:-1]
+          continue
+
+        if merge_line:
+          line = merge_line + line
+          merge_line = ''
+
+        statement = line[:line.find(' ')]
+        if statement == 'build':
+          # Save the dependency list as a raw string. Only the lines needed will
+          # be processed with raw_build_to_deps(). This saves a good 70ms of
+          # processing time.
+          build_target, dependencies = line[6:].split(': ', 1)
+          # Interestingly, trying to be smart and only saving the build steps
+          # with the intended extensions ('', '.stamp', '.so') slows down
+          # parsing even if 90% of the build rules can be skipped.
+          # On Windows, a single step may generate two target, so split items
+          # accordingly. It has only been seen for .exe/.exe.pdb combos.
+          for i in build_target.strip().split():
+            build_steps[i] = dependencies
+        elif statement == 'subninja':
+          subninja.append(line[9:])
+  except IOError:
+    print >> sys.stderr, 'Failed to open %s' % ninja_path
+    raise
+
+  total = 1
+  for rel_path in subninja:
+    try:
+      # Load each of the files referenced.
+      # TODO(maruel): Skip the files known to not be needed. It saves an aweful
+      # lot of processing time.
+      total += load_ninja_recursively(build_dir, rel_path, build_steps)
+    except IOError:
+      print >> sys.stderr, '... as referenced by %s' % ninja_path
+      raise
+  return total
+
+
+def load_ninja(build_dir):
+  """Loads the tree of .ninja files in build_dir."""
+  build_steps = {}
+  total = load_ninja_recursively(build_dir, 'build.ninja', build_steps)
+  logging.info('Loaded %d ninja files, %d build steps', total, len(build_steps))
+  return build_steps
+
+
+def using_blacklist(item):
+  """Returns True if an item should be analyzed.
+
+  Ignores many rules that are assumed to not depend on a dynamic library. If
+  the assumption doesn't hold true anymore for a file format, remove it from
+  this list. This is simply an optimization.
+  """
+  # *.json is ignored below, *.isolated.gen.json is an exception, it is produced
+  # by isolate_driver.py in 'test_isolation_mode==prepare'.
+  if item.endswith('.isolated.gen.json'):
+    return True
+  IGNORED = (
+    '.a', '.cc', '.css', '.dat', '.def', '.frag', '.h', '.html', '.isolate',
+    '.js', '.json', '.manifest', '.o', '.obj', '.pak', '.png', '.pdb', '.py',
+    '.strings', '.test', '.txt', '.vert',
+  )
+  # ninja files use native path format.
+  ext = os.path.splitext(item)[1]
+  if ext in IGNORED:
+    return False
+  # Special case Windows, keep .dll.lib but discard .lib.
+  if item.endswith('.dll.lib'):
+    return True
+  if ext == '.lib':
+    return False
+  return item not in ('', '|', '||')
+
+
+def raw_build_to_deps(item):
+  """Converts a raw ninja build statement into the list of interesting
+  dependencies.
+  """
+  # TODO(maruel): Use a whitelist instead? .stamp, .so.TOC, .dylib.TOC,
+  # .dll.lib, .exe and empty.
+  # The first item is the build rule, e.g. 'link', 'cxx', 'phony', etc.
+  return filter(using_blacklist, item.split(' ')[1:])
+
+
+def collect_deps(target, build_steps, dependencies_added, rules_seen):
+  """Recursively adds all the interesting dependencies for |target|
+  into |dependencies_added|.
+  """
+  if rules_seen is None:
+    rules_seen = set()
+  if target in rules_seen:
+    # TODO(maruel): Figure out how it happens.
+    logging.warning('Circular dependency for %s!', target)
+    return
+  rules_seen.add(target)
+  try:
+    dependencies = raw_build_to_deps(build_steps[target])
+  except KeyError:
+    logging.info('Failed to find a build step to generate: %s', target)
+    return
+  logging.debug('collect_deps(%s) -> %s', target, dependencies)
+  for dependency in dependencies:
+    dependencies_added.add(dependency)
+    collect_deps(dependency, build_steps, dependencies_added, rules_seen)
+
+
+def post_process_deps(build_dir, dependencies):
+  """Processes the dependency list with OS specific rules."""
+  def filter_item(i):
+    if i.endswith('.so.TOC'):
+      # Remove only the suffix .TOC, not the .so!
+      return i[:-4]
+    if i.endswith('.dylib.TOC'):
+      # Remove only the suffix .TOC, not the .dylib!
+      return i[:-4]
+    if i.endswith('.dll.lib'):
+      # Remove only the suffix .lib, not the .dll!
+      return i[:-4]
+    return i
+
+  def is_exe(i):
+    # This script is only for adding new binaries that are created as part of
+    # the component build.
+    ext = os.path.splitext(i)[1]
+    # On POSIX, executables have no extension.
+    if ext not in ('', '.dll', '.dylib', '.exe', '.nexe', '.so'):
+      return False
+    if os.path.isabs(i):
+      # In some rare case, there's dependency set explicitly on files outside
+      # the checkout.
+      return False
+
+    # Check for execute access and strip directories. This gets rid of all the
+    # phony rules.
+    p = os.path.join(build_dir, i)
+    return os.access(p, os.X_OK) and not os.path.isdir(p)
+
+  return filter(is_exe, map(filter_item, dependencies))
+
+
+def create_wrapper(args, isolate_index, isolated_index):
+  """Creates a wrapper .isolate that add dynamic libs.
+
+  The original .isolate is not modified.
+  """
+  cwd = os.getcwd()
+  isolate = args[isolate_index]
+  # The code assumes the .isolate file is always specified path-less in cwd. Fix
+  # if this assumption doesn't hold true.
+  assert os.path.basename(isolate) == isolate, isolate
+
+  # This will look like ../out/Debug. This is based against cwd. Note that this
+  # must equal the value provided as PRODUCT_DIR.
+  build_dir = os.path.dirname(args[isolated_index])
+
+  # This will look like chrome/unit_tests.isolate. It is based against SRC_DIR.
+  # It's used to calculate temp_isolate.
+  src_isolate = os.path.relpath(os.path.join(cwd, isolate), SRC_DIR)
+
+  # The wrapping .isolate. This will look like
+  # ../out/Debug/gen/chrome/unit_tests.isolate.
+  temp_isolate = os.path.join(build_dir, 'gen', src_isolate)
+  temp_isolate_dir = os.path.dirname(temp_isolate)
+
+  # Relative path between the new and old .isolate file.
+  isolate_relpath = os.path.relpath(
+      '.', temp_isolate_dir).replace(os.path.sep, '/')
+
+  # It's a big assumption here that the name of the isolate file matches the
+  # primary target '_run'. Fix accordingly if this doesn't hold true, e.g.
+  # complain to maruel@.
+  target = isolate[:-len('.isolate')] + '_run'
+  build_steps = load_ninja(build_dir)
+  binary_deps = set()
+  collect_deps(target, build_steps, binary_deps, None)
+  binary_deps = post_process_deps(build_dir, binary_deps)
+  logging.debug(
+      'Binary dependencies:%s', ''.join('\n  ' + i for i in binary_deps))
+
+  # Now do actual wrapping .isolate.
+  isolate_dict = {
+    'includes': [
+      posixpath.join(isolate_relpath, isolate),
+    ],
+    'variables': {
+      # Will look like ['<(PRODUCT_DIR)/lib/flibuser_prefs.so'].
+      'files': sorted(
+          '<(PRODUCT_DIR)/%s' % i.replace(os.path.sep, '/')
+          for i in binary_deps),
+    },
+  }
+  # Some .isolate files have the same temp directory and the build system may
+  # run this script in parallel so make directories safely here.
+  try:
+    os.makedirs(temp_isolate_dir)
+  except OSError as e:
+    if e.errno != errno.EEXIST:
+      raise
+  comment = (
+      '# Warning: this file was AUTOGENERATED.\n'
+      '# DO NO EDIT.\n')
+  out = StringIO.StringIO()
+  isolate_format.print_all(comment, isolate_dict, out)
+  isolate_content = out.getvalue()
+  with open(temp_isolate, 'wb') as f:
+    f.write(isolate_content)
+  logging.info('Added %d dynamic libs', len(binary_deps))
+  logging.debug('%s', isolate_content)
+  args[isolate_index] = temp_isolate
 
 
 def prepare_isolate_call(args, output):
   """Gathers all information required to run isolate.py later.
 
   Dumps it as JSON to |output| file.
   """
   with open(output, 'wb') as f:
     json.dump({
       'args': args,
       'dir': os.getcwd(),
       'version': 1,
     }, f, indent=2, sort_keys=True)
 
-def rebase_directories(args, abs_base):
-  """Rebases all paths to be relative to abs_base."""
-  def replace(index):
-    args[index] = os.path.relpath(os.path.abspath(args[index]), abs_base)
-  for i, arg in enumerate(args):
-    if arg in ['--isolate', '--isolated']:
-      replace(i + 1)
-    if arg == '--path-variable':
-      # Path variables have a triple form: --path-variable NAME <path>.
-      replace(i + 2)
 
 def main():
   logging.basicConfig(level=logging.ERROR, format='%(levelname)7s %(message)s')
-  if len(sys.argv) < 2:
-    print >> sys.stderr, 'Internal failure; mode required'
-    return 1
-  mode = sys.argv[1]
   args = sys.argv[1:]
+  mode = args[0] if args else None
   isolate = None
   isolated = None
   for i, arg in enumerate(args):
     if arg == '--isolate':
       isolate = i + 1
     if arg == '--isolated':
       isolated = i + 1
-  if not isolate or not isolated:
+  if isolate is None or isolated is None or not mode:
     print >> sys.stderr, 'Internal failure'
     return 1
 
-  # Make sure all paths are relative to the isolate file. This is an
-  # expectation of the go binaries. In gn, this script is not called
-  # relative to the isolate file, but relative to the product dir.
-  new_base = os.path.abspath(os.path.dirname(args[isolate]))
-  rebase_directories(args, new_base)
-  assert args[isolate] == os.path.basename(args[isolate])
-  os.chdir(new_base)
+  create_wrapper(args, isolate, isolated)
 
   # In 'prepare' mode just collect all required information for postponed
   # isolated.py invocation later, store it in *.isolated.gen.json file.
   if mode == 'prepare':
     prepare_isolate_call(args[1:], args[isolated] + '.gen.json')
     return 0
 
-  swarming_client = os.path.join(TOOLS_DIR, 'swarming_client')
+  swarming_client = os.path.join(SRC_DIR, 'tools', 'swarming_client')
   sys.stdout.flush()
-  return subprocess.call(
+  result = subprocess.call(
       [sys.executable, os.path.join(swarming_client, 'isolate.py')] + args)
+  return result
 
 
 if __name__ == '__main__':
   sys.exit(main())