Index: mojo/public/python/mojo_bindings/serialization.py |
diff --git a/mojo/public/python/mojo_bindings/serialization.py b/mojo/public/python/mojo_bindings/serialization.py |
deleted file mode 100644 |
index b5ea1bd8a9f3d2e420c3c3db023d4889fd441cb6..0000000000000000000000000000000000000000 |
--- a/mojo/public/python/mojo_bindings/serialization.py |
+++ /dev/null |
@@ -1,193 +0,0 @@ |
-# Copyright 2014 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. |
- |
-"""Utility classes for serialization""" |
- |
-import struct |
- |
- |
-# Format of a header for a struct or an array. |
-HEADER_STRUCT = struct.Struct("<II") |
- |
- |
-class SerializationException(Exception): |
- """Error when strying to serialize a struct.""" |
- pass |
- |
- |
-class DeserializationException(Exception): |
- """Error when strying to deserialize a struct.""" |
- pass |
- |
- |
-class DeserializationContext(object): |
- |
- def ClaimHandle(self, handle): |
- raise NotImplementedError() |
- |
- def ClaimMemory(self, start, size): |
- raise NotImplementedError() |
- |
- def GetSubContext(self, offset): |
- raise NotImplementedError() |
- |
- def IsInitialContext(self): |
- raise NotImplementedError() |
- |
- |
-class RootDeserializationContext(DeserializationContext): |
- def __init__(self, data, handles): |
- if isinstance(data, buffer): |
- self.data = data |
- else: |
- self.data = buffer(data) |
- self._handles = handles |
- self._next_handle = 0; |
- self._next_memory = 0; |
- |
- def ClaimHandle(self, handle): |
- if handle < self._next_handle: |
- raise DeserializationException('Accessing handles out of order.') |
- self._next_handle = handle + 1 |
- return self._handles[handle] |
- |
- def ClaimMemory(self, start, size): |
- if start < self._next_memory: |
- raise DeserializationException('Accessing buffer out of order.') |
- self._next_memory = start + size |
- |
- def GetSubContext(self, offset): |
- return _ChildDeserializationContext(self, offset) |
- |
- def IsInitialContext(self): |
- return True |
- |
- |
-class _ChildDeserializationContext(DeserializationContext): |
- def __init__(self, parent, offset): |
- self._parent = parent |
- self._offset = offset |
- self.data = buffer(parent.data, offset) |
- |
- def ClaimHandle(self, handle): |
- return self._parent.ClaimHandle(handle) |
- |
- def ClaimMemory(self, start, size): |
- return self._parent.ClaimMemory(self._offset + start, size) |
- |
- def GetSubContext(self, offset): |
- return self._parent.GetSubContext(self._offset + offset) |
- |
- def IsInitialContext(self): |
- return False |
- |
- |
-class Serialization(object): |
- """ |
- Helper class to serialize/deserialize a struct. |
- """ |
- def __init__(self, groups): |
- self.version = _GetVersion(groups) |
- self._groups = groups |
- main_struct = _GetStruct(groups) |
- self.size = HEADER_STRUCT.size + main_struct.size |
- self._struct_per_version = { |
- self.version: main_struct, |
- } |
- self._groups_per_version = { |
- self.version: groups, |
- } |
- |
- def _GetMainStruct(self): |
- return self._GetStruct(self.version) |
- |
- def _GetGroups(self, version): |
- # If asking for a version greater than the last known. |
- version = min(version, self.version) |
- if version not in self._groups_per_version: |
- self._groups_per_version[version] = _FilterGroups(self._groups, version) |
- return self._groups_per_version[version] |
- |
- def _GetStruct(self, version): |
- # If asking for a version greater than the last known. |
- version = min(version, self.version) |
- if version not in self._struct_per_version: |
- self._struct_per_version[version] = _GetStruct(self._GetGroups(version)) |
- return self._struct_per_version[version] |
- |
- def Serialize(self, obj, handle_offset): |
- """ |
- Serialize the given obj. handle_offset is the the first value to use when |
- encoding handles. |
- """ |
- handles = [] |
- data = bytearray(self.size) |
- HEADER_STRUCT.pack_into(data, 0, self.size, self.version) |
- position = HEADER_STRUCT.size |
- to_pack = [] |
- for group in self._groups: |
- position = position + NeededPaddingForAlignment(position, |
- group.GetByteSize()) |
- (entry, new_handles) = group.Serialize( |
- obj, |
- len(data) - position, |
- data, |
- handle_offset + len(handles)) |
- to_pack.append(entry) |
- handles.extend(new_handles) |
- position = position + group.GetByteSize() |
- self._GetMainStruct().pack_into(data, HEADER_STRUCT.size, *to_pack) |
- return (data, handles) |
- |
- def Deserialize(self, fields, context): |
- if len(context.data) < HEADER_STRUCT.size: |
- raise DeserializationException( |
- 'Available data too short to contain header.') |
- (size, version) = HEADER_STRUCT.unpack_from(context.data) |
- if len(context.data) < size or size < HEADER_STRUCT.size: |
- raise DeserializationException('Header size is incorrect.') |
- if context.IsInitialContext(): |
- context.ClaimMemory(0, size) |
- version_struct = self._GetStruct(version) |
- entitities = version_struct.unpack_from(context.data, HEADER_STRUCT.size) |
- filtered_groups = self._GetGroups(version) |
- position = HEADER_STRUCT.size |
- for (group, value) in zip(filtered_groups, entitities): |
- position = position + NeededPaddingForAlignment(position, |
- group.GetByteSize()) |
- fields.update(group.Deserialize(value, context.GetSubContext(position))) |
- position += group.GetByteSize() |
- |
- |
-def NeededPaddingForAlignment(value, alignment=8): |
- """Returns the padding necessary to align value with the given alignment.""" |
- if value % alignment: |
- return alignment - (value % alignment) |
- return 0 |
- |
- |
-def _GetVersion(groups): |
- return sum([len(x.descriptors) for x in groups]) |
- |
- |
-def _FilterGroups(groups, version): |
- return [group for group in groups if group.GetVersion() < version] |
- |
- |
-def _GetStruct(groups): |
- index = 0 |
- codes = [ '<' ] |
- for group in groups: |
- code = group.GetTypeCode() |
- size = group.GetByteSize() |
- needed_padding = NeededPaddingForAlignment(index, size) |
- if needed_padding: |
- codes.append('x' * needed_padding) |
- index = index + needed_padding |
- codes.append(code) |
- index = index + size |
- alignment_needed = NeededPaddingForAlignment(index) |
- if alignment_needed: |
- codes.append('x' * alignment_needed) |
- return struct.Struct(''.join(codes)) |