Move //mojo/{public, edk} underneath //third_party

mojo/public/tools/bindings/pylib/mojom/generate/pack.py

-# 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.
-
-import module as mojom
-
-# This module provides a mechanism for determining the packed order and offsets
-# of a mojom.Struct.
-#
-# ps = pack.PackedStruct(struct)
-# ps.packed_fields will access a list of PackedField objects, each of which
-# will have an offset, a size and a bit (for mojom.BOOLs).
-
-class PackedField(object):
-  kind_to_size = {
-    mojom.BOOL:                  1,
-    mojom.INT8:                  1,
-    mojom.UINT8:                 1,
-    mojom.INT16:                 2,
-    mojom.UINT16:                2,
-    mojom.INT32:                 4,
-    mojom.UINT32:                4,
-    mojom.FLOAT:                 4,
-    mojom.HANDLE:                4,
-    mojom.MSGPIPE:               4,
-    mojom.SHAREDBUFFER:          4,
-    mojom.DCPIPE:                4,
-    mojom.DPPIPE:                4,
-    mojom.NULLABLE_HANDLE:       4,
-    mojom.NULLABLE_MSGPIPE:      4,
-    mojom.NULLABLE_SHAREDBUFFER: 4,
-    mojom.NULLABLE_DCPIPE:       4,
-    mojom.NULLABLE_DPPIPE:       4,
-    mojom.INT64:                 8,
-    mojom.UINT64:                8,
-    mojom.DOUBLE:                8,
-    mojom.STRING:                8,
-    mojom.NULLABLE_STRING:       8
-  }
-
-  @classmethod
-  def GetSizeForKind(cls, kind):
-    if isinstance(kind, (mojom.Array, mojom.Map, mojom.Struct)):
-      return 8
-    if isinstance(kind, mojom.Interface) or \
-       isinstance(kind, mojom.InterfaceRequest):
-      kind = mojom.MSGPIPE
-    if isinstance(kind, mojom.Enum):
-      # TODO(mpcomplete): what about big enums?
-      return cls.kind_to_size[mojom.INT32]
-    if not kind in cls.kind_to_size:
-      raise Exception("Invalid kind: %s" % kind.spec)
-    return cls.kind_to_size[kind]
-
-  def __init__(self, field, index, ordinal):
-    """
-    Args:
-      field: the original field.
-      index: the position of the original field in the struct.
-      ordinal: the ordinal of the field for serialization.
-    """
-    self.field = field
-    self.index = index
-    self.ordinal = ordinal
-    self.size = self.GetSizeForKind(field.kind)
-    self.offset = None
-    self.bit = None
-
-
-# Returns the pad necessary to reserve space for alignment of |size|.
-def GetPad(offset, size):
-  return (size - (offset % size)) % size
-
-
-# Returns a 2-tuple of the field offset and bit (for BOOLs)
-def GetFieldOffset(field, last_field):
-  if field.field.kind == mojom.BOOL and \
-      last_field.field.kind == mojom.BOOL and \
-      last_field.bit < 7:
-    return (last_field.offset, last_field.bit + 1)
-
-  offset = last_field.offset + last_field.size
-  pad = GetPad(offset, field.size)
-  return (offset + pad, 0)
-
-
-class PackedStruct(object):
-  def __init__(self, struct):
-    self.struct = struct
-    self.packed_fields = []
-
-    # No fields.
-    if (len(struct.fields) == 0):
-      return
-
-    # Start by sorting by ordinal.
-    src_fields = []
-    ordinal = 0
-    for index, field in enumerate(struct.fields):
-      if field.ordinal is not None:
-        ordinal = field.ordinal
-      src_fields.append(PackedField(field, index, ordinal))
-      ordinal += 1
-    src_fields.sort(key=lambda field: field.ordinal)
-
-    src_field = src_fields[0]
-    src_field.offset = 0
-    src_field.bit = 0
-    # dst_fields will contain each of the fields, in increasing offset order.
-    dst_fields = self.packed_fields
-    dst_fields.append(src_field)
-
-    # Then find first slot that each field will fit.
-    for src_field in src_fields[1:]:
-      last_field = dst_fields[0]
-      for i in xrange(1, len(dst_fields)):
-        next_field = dst_fields[i]
-        offset, bit = GetFieldOffset(src_field, last_field)
-        if offset + src_field.size <= next_field.offset:
-          # Found hole.
-          src_field.offset = offset
-          src_field.bit = bit
-          dst_fields.insert(i, src_field)
-          break
-        last_field = next_field
-      if src_field.offset is None:
-        # Add to end
-        src_field.offset, src_field.bit = GetFieldOffset(src_field, last_field)
-        dst_fields.append(src_field)
-
-  def GetTotalSize(self):
-    if not self.packed_fields:
-      return 0
-    last_field = self.packed_fields[-1]
-    offset = last_field.offset + last_field.size
-    pad = GetPad(offset, 8)
-    return offset + pad
-
-
-class ByteInfo(object):
-  def __init__(self):
-    self.is_padding = False
-    self.packed_fields = []
-
-
-def GetByteLayout(packed_struct):
-  bytes = [ByteInfo() for i in xrange(packed_struct.GetTotalSize())]
-
-  limit_of_previous_field = 0
-  for packed_field in packed_struct.packed_fields:
-    for i in xrange(limit_of_previous_field, packed_field.offset):
-      bytes[i].is_padding = True
-    bytes[packed_field.offset].packed_fields.append(packed_field)
-    limit_of_previous_field = packed_field.offset + packed_field.size
-
-  for i in xrange(limit_of_previous_field, len(bytes)):
-    bytes[i].is_padding = True
-
-  for byte in bytes:
-    # A given byte cannot both be padding and have a fields packed into it.
-    assert not (byte.is_padding and byte.packed_fields)
-
-  return bytes