Revert of Enable the ninja parsing code all the time.

tools/isolate_driver.py

Index: tools/isolate_driver.py
diff --git a/tools/isolate_driver.py b/tools/isolate_driver.py
index bf1103a4df01d79276887cce479228a50a19afe7..4db823e444935fec4f6d95d4951246b6f2cbdd23 100755
--- a/tools/isolate_driver.py
+++ b/tools/isolate_driver.py
@@ -20,21 +20,170 @@
 """
 
 import StringIO
+import glob
 import logging
 import os
 import posixpath
 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)
 
-import ninja_parser
-
 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.
+  """
+  IGNORED = (
+    '.a', '.cc', '.css', '.def', '.h', '.html', '.js', '.json', '.manifest',
+    '.o', '.obj', '.pak', '.png', '.pdb', '.strings', '.txt',
+  )
+  # 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 recurse(target, build_steps, rules_seen):
+  """Recursively returns all the interesting dependencies for root_item."""
+  out = []
+  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('recurse(%s) -> %s', target, dependencies)
+  for dependency in dependencies:
+    out.append(dependency)
+    dependency_raw_dependencies = build_steps.get(dependency)
+    if dependency_raw_dependencies:
+      for i in raw_build_to_deps(dependency_raw_dependencies):
+        out.extend(recurse(i, build_steps, rules_seen))
+    else:
+      logging.info('Failed to find a build step to generate: %s', dependency)
+  return out
+
+
+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
+
+  # Check for execute access. This gets rid of all the phony rules.
+  return [
+    i for i in map(filter_item, dependencies)
+    if os.access(os.path.join(build_dir, i), os.X_OK)
+  ]
 
 
 def create_wrapper(args, isolate_index, isolated_index):
@@ -69,9 +218,8 @@
   # primary target '_run'. Fix accordingly if this doesn't hold true, e.g.
   # complain to maruel@.
   target = isolate[:-len('.isolate')] + '_run'
-  build_steps = ninja_parser.load_ninja(build_dir)
-  binary_deps = ninja_parser.post_process_deps(
-      build_dir, ninja_parser.recurse(build_dir, target, build_steps))
+  build_steps = load_ninja(build_dir)
+  binary_deps = post_process_deps(build_dir, recurse(target, build_steps, None))
   logging.debug(
       'Binary dependencies:%s', ''.join('\n  ' + i for i in binary_deps))
 
@@ -107,16 +255,20 @@
   args = sys.argv[1:]
   isolate = None
   isolated = None
+  is_component = False
   for i, arg in enumerate(args):
     if arg == '--isolate':
       isolate = i + 1
     if arg == '--isolated':
       isolated = i + 1
+    if arg == 'component=shared_library':
+      is_component = True
   if isolate is None or isolated is None:
     print >> sys.stderr, 'Internal failure'
     return 1
 
-  create_wrapper(args, isolate, isolated)
+  if is_component:
+    create_wrapper(args, isolate, isolated)
 
   swarming_client = os.path.join(SRC_DIR, 'tools', 'swarming_client')
   sys.stdout.flush()