1 files changed, 97 insertions, 0 deletions
diff --git a/third_party/libwebrtc/build/android/gyp/util/zipalign.py b/third_party/libwebrtc/build/android/gyp/util/zipalign.py
new file mode 100644
index 0000000000..c5c4ea88c6
--- /dev/null
+++ b/third_party/libwebrtc/build/android/gyp/util/zipalign.py
@@ -0,0 +1,97 @@
+# Copyright 2019 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 struct
+import sys
+import zipfile
+
+from util import build_utils
+
+_FIXED_ZIP_HEADER_LEN = 30
+
+
+def _PatchedDecodeExtra(self):
+  # Try to decode the extra field.
+  extra = self.extra
+  unpack = struct.unpack
+  while len(extra) >= 4:
+    tp, ln = unpack('<HH', extra[:4])
+    if tp == 1:
+      if ln >= 24:
+        counts = unpack('<QQQ', extra[4:28])
+      elif ln == 16:
+        counts = unpack('<QQ', extra[4:20])
+      elif ln == 8:
+        counts = unpack('<Q', extra[4:12])
+      elif ln == 0:
+        counts = ()
+      else:
+        raise RuntimeError("Corrupt extra field %s" % (ln, ))
+
+      idx = 0
+
+      # ZIP64 extension (large files and/or large archives)
+      if self.file_size in (0xffffffffffffffff, 0xffffffff):
+        self.file_size = counts[idx]
+        idx += 1
+
+      if self.compress_size == 0xffffffff:
+        self.compress_size = counts[idx]
+        idx += 1
+
+      if self.header_offset == 0xffffffff:
+        self.header_offset = counts[idx]
+        idx += 1
+
+    extra = extra[ln + 4:]
+
+
+def ApplyZipFileZipAlignFix():
+  """Fix zipfile.ZipFile() to be able to open zipaligned .zip files.
+
+  Android's zip alignment uses not-quite-valid zip headers to perform alignment.
+  Python < 3.4 crashes when trying to load them.
+  https://bugs.python.org/issue14315
+  """
+  if sys.version_info < (3, 4):
+    zipfile.ZipInfo._decodeExtra = (  # pylint: disable=protected-access
+        _PatchedDecodeExtra)
+
+
+def _SetAlignment(zip_obj, zip_info, alignment):
+  """Sets a ZipInfo's extra field such that the file will be aligned.
+
+  Args:
+    zip_obj: The ZipFile object that is being written.
+    zip_info: The ZipInfo object about to be written.
+    alignment: The amount of alignment (e.g. 4, or 4*1024).
+  """
+  cur_offset = zip_obj.fp.tell()
+  header_size = _FIXED_ZIP_HEADER_LEN + len(zip_info.filename)
+  padding_needed = (alignment - (
+      (cur_offset + header_size) % alignment)) % alignment
+
+
+  # Python writes |extra| to both the local file header and the central
+  # directory's file header. Android's zipalign tool writes only to the
+  # local file header, so there is more overhead in using python to align.
+  zip_info.extra = b'\0' * padding_needed
+
+
+def AddToZipHermetic(zip_file,
+                     zip_path,
+                     src_path=None,
+                     data=None,
+                     compress=None,
+                     alignment=None):
+  """Same as build_utils.AddToZipHermetic(), but with alignment.
+
+  Args:
+    alignment: If set, align the data of the entry to this many bytes.
+  """
+  zipinfo = build_utils.HermeticZipInfo(filename=zip_path)
+  if alignment:
+    _SetAlignment(zip_file, zipinfo, alignment)
+  build_utils.AddToZipHermetic(
+      zip_file, zipinfo, src_path=src_path, data=data, compress=compress)