FREEZE.unindexed

tools/binary_size/ninja_parser.py

Index: tools/binary_size/ninja_parser.py
diff --git a/tools/binary_size/ninja_parser.py b/tools/binary_size/ninja_parser.py
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+++ b/tools/binary_size/ninja_parser.py
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+# Copyright 2017 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.
+"""Extract source file information from .ninja files."""
+
+import logging
+import os
+import re
+
+
+# E.g.:
+# build obj/.../foo.o: cxx gen/.../foo.cc || obj/.../foo.inputdeps.stamp
+# build obj/.../libfoo.a: alink obj/.../a.o obj/.../b.o |
+_REGEX = re.compile(r'build ([^:]+?\.[ao]): \w+ (.*?)(?: \||\n|$)')
+
+
+class SourceFileMapper(object):
+  def __init__(self, output_directory):
+    self._output_directory = output_directory
+    self._ninja_files_to_parse = ['build.ninja']
+    self._seen_ninja_files = set(('build.ninja',))
+    self._dep_map = {}
+
+  def _ParseNinja(self, path):
+    with open(os.path.join(self._output_directory, path)) as obj:
+      self._ParseNinjaLines(obj)
+
+  def _ParseNinjaLines(self, lines):
+    dep_map = self._dep_map
+    sub_ninjas = []
+    for line in lines:
+      if line.startswith('subninja '):
+        subpath = line[9:-1]
+        assert subpath not in self._seen_ninja_files, (
+            'Double include of ' + subpath)
+        self._seen_ninja_files.add(subpath)
+        sub_ninjas.append(subpath)
+        continue
+      m = _REGEX.match(line)
+      if m:
+        output, srcs = m.groups()
+        output = output.replace('\\ ', ' ')
+        assert output not in dep_map, 'Duplicate output: ' + output
+        if output[-1] == 'o':
+          dep_map[output] = srcs.replace('\\ ', ' ')
+        else:
+          srcs = srcs.replace('\\ ', '\b')
+          obj_paths = (s.replace('\b', ' ') for s in srcs.split(' '))
+          dep_map[output] = {os.path.basename(p): p for p in obj_paths}
+
+    # Add reversed so that the first on encoundered is at the top of the stack.
+    self._ninja_files_to_parse.extend(reversed(sub_ninjas))
+
+  def _Lookup(self, path):
+    """Looks for |path| within self._dep_map.
+
+    If not found, continues to parse subninjas until it is found or there are no
+    more subninjas.
+    """
+    ret = self._dep_map.get(path)
+    while not ret and self._ninja_files_to_parse:
+      self._ParseNinja(self._ninja_files_to_parse.pop())
+      ret = self._dep_map.get(path)
+    return ret
+
+  def FindSourceForPath(self, path):
+    """Returns the source path for the given object path (or None if not found).
+
+    Paths for objects within archives should be in the format: foo/bar.a(baz.o)
+    """
+    if not path.endswith(')'):
+      return self._Lookup(path)
+
+    # foo/bar.a(baz.o)
+    start_idx = path.index('(')
+    lib_name = path[:start_idx]
+    obj_name = path[start_idx + 1:-1]
+    by_basename = self._Lookup(lib_name)
+    if not by_basename:
+      return None
+    obj_path = by_basename.get(obj_name)
+    if not obj_path:
+      # Found the library, but it doesn't list the .o file.
+      logging.warning('no obj basename for %s', path)
+      return None
+    return self._Lookup(obj_path)
+
+  def GetParsedFileCount(self):
+    return len(self._seen_ninja_files)