Make write_library_dependencies.py find all transitive dependencies

build/android/gyp/write_ordered_libraries.py

Index: build/android/gyp/write_ordered_libraries.py
diff --git a/build/android/gyp/write_ordered_libraries.py b/build/android/gyp/write_ordered_libraries.py
new file mode 100755
index 0000000000000000000000000000000000000000..4ca54cd62da4719e7c3158c49d4d89a563fffc8b
--- /dev/null
+++ b/build/android/gyp/write_ordered_libraries.py
@@ -0,0 +1,123 @@
+#!/usr/bin/env python
+#
+# Copyright 2013 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.
+
+"""Writes dependency ordered list of native libraries.
+
+The list excludes any Android system libraries, as those are not bundled with
+the APK.
+
+This list of libraries is used for several steps of building an APK.
+In the component build, the --input-libraries only needs to be the top-level
+library (i.e. libcontent_shell_content_view). This will then use readelf to
+inspect the shared libraries and determine the full list of (non-system)
+libraries that should be included in the APK.
+"""
+
+# TODO(cjhopman): See if we can expose the list of library dependencies from
+# gyp, rather than calculating it ourselves.
+# http://crbug.com/225558
+
+import json
+import optparse
+import os
+import re
+import sys
+
+BUILD_ANDROID_DIR = os.path.join(os.path.dirname(__file__), '..')
+sys.path.append(BUILD_ANDROID_DIR)
+
+from pylib import build_utils
+
+
+_options = None
+_libraries_dir = None
+_library_re = re.compile(
+    '.*NEEDED.*Shared library: \[(?P<library_name>[\w/.]+)\]')
+
+
+def FullLibraryPath(library_name):
+  return '%s/%s' % (_libraries_dir, library_name)
+
+
+def IsSystemLibrary(library_name):
+  # If the library doesn't exist in the libraries directory, assume that it is
+  # an Android system library.
+  return not os.path.exists(FullLibraryPath(library_name))
+
+
+def CallReadElf(library_name):
+  readelf_cmd = [_options.readelf,
+                 '-d',
+                 FullLibraryPath(library_name)]
+  return build_utils.CheckCallDie(readelf_cmd)
+
+
+def GetDependencies(library_name):
+  elf = CallReadElf(library_name)
+  return set(_library_re.findall(elf))
+
+
+def GetNonSystemDependencies(library_name):
+  all_deps = GetDependencies(library_name)
+  return set((lib for lib in all_deps if not IsSystemLibrary(lib)))
+
+
+def GetSortedTransitiveDependencies(libraries):
+  """Returns all transitive library dependencies in dependency order."""
+  def GraphNode(library):
+    return (library, GetNonSystemDependencies(library))
+
+  # First: find all library dependencies.
+  unchecked_deps = libraries
+  all_deps = set(libraries)
+  while unchecked_deps:
+    lib = unchecked_deps.pop()
+    new_deps = GetNonSystemDependencies(lib).difference(all_deps)
+    unchecked_deps.extend(new_deps)
+    all_deps = all_deps.union(new_deps)
+
+  # Then: simple, slow topological sort.
+  sorted_deps = []
+  unsorted_deps = dict(map(GraphNode, all_deps))
+  while unsorted_deps:
+    for library, dependencies in unsorted_deps.items():
+      if not dependencies.intersection(unsorted_deps.keys()):
+        sorted_deps.append(library)
+        del unsorted_deps[library]
+
+  return sorted_deps
+
+
+def main(argv):
+  parser = optparse.OptionParser()
+
+  parser.add_option('--input-libraries',
+      help='A list of top-level input libraries.')
+  parser.add_option('--readelf', help='Path to the readelf binary.')
+  parser.add_option('--output', help='Path to the generated .json file.')
+  parser.add_option('--stamp', help='Path to touch on success.')
+
+  global _options
+  _options, _ = parser.parse_args()
+
+  libraries = build_utils.ParseGypList(_options.input_libraries)
+  global _libraries_dir
+  _libraries_dir = os.path.dirname(libraries[0])
+  libraries = [os.path.basename(lib) for lib in libraries]
+
+  libraries = GetSortedTransitiveDependencies(libraries)
+
+  with open(_options.output, 'w') as outfile:
+    json.dump(libraries, outfile)
+
+  if _options.stamp:
+    build_utils.Touch(_options.stamp)
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv))
+
+