Initial Contribution
diff --git a/froofle/protobuf/internal/wire_format.py b/froofle/protobuf/internal/wire_format.py
new file mode 100644
index 0000000..4d823c8
--- /dev/null
+++ b/froofle/protobuf/internal/wire_format.py
@@ -0,0 +1,236 @@
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc. All rights reserved.
+# http://code.google.com/p/protobuf/
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+# * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Constants and static functions to support protocol buffer wire format."""
+
+__author__ = 'robinson@google.com (Will Robinson)'
+
+import struct
+from froofle.protobuf import message
+
+
+TAG_TYPE_BITS = 3 # Number of bits used to hold type info in a proto tag.
+_TAG_TYPE_MASK = (1 << TAG_TYPE_BITS) - 1 # 0x7
+
+# These numbers identify the wire type of a protocol buffer value.
+# We use the least-significant TAG_TYPE_BITS bits of the varint-encoded
+# tag-and-type to store one of these WIRETYPE_* constants.
+# These values must match WireType enum in //net/proto2/public/wire_format.h.
+WIRETYPE_VARINT = 0
+WIRETYPE_FIXED64 = 1
+WIRETYPE_LENGTH_DELIMITED = 2
+WIRETYPE_START_GROUP = 3
+WIRETYPE_END_GROUP = 4
+WIRETYPE_FIXED32 = 5
+_WIRETYPE_MAX = 5
+
+
+# Bounds for various integer types.
+INT32_MAX = int((1 << 31) - 1)
+INT32_MIN = int(-(1 << 31))
+UINT32_MAX = (1 << 32) - 1
+
+INT64_MAX = (1 << 63) - 1
+INT64_MIN = -(1 << 63)
+UINT64_MAX = (1 << 64) - 1
+
+# "struct" format strings that will encode/decode the specified formats.
+FORMAT_UINT32_LITTLE_ENDIAN = '<I'
+FORMAT_UINT64_LITTLE_ENDIAN = '<Q'
+
+
+# We'll have to provide alternate implementations of AppendLittleEndian*() on
+# any architectures where these checks fail.
+if struct.calcsize(FORMAT_UINT32_LITTLE_ENDIAN) != 4:
+ raise AssertionError('Format "I" is not a 32-bit number.')
+if struct.calcsize(FORMAT_UINT64_LITTLE_ENDIAN) != 8:
+ raise AssertionError('Format "Q" is not a 64-bit number.')
+
+
+def PackTag(field_number, wire_type):
+ """Returns an unsigned 32-bit integer that encodes the field number and
+ wire type information in standard protocol message wire format.
+
+ Args:
+ field_number: Expected to be an integer in the range [1, 1 << 29)
+ wire_type: One of the WIRETYPE_* constants.
+ """
+ if not 0 <= wire_type <= _WIRETYPE_MAX:
+ raise message.EncodeError('Unknown wire type: %d' % wire_type)
+ return (field_number << TAG_TYPE_BITS) | wire_type
+
+
+def UnpackTag(tag):
+ """The inverse of PackTag(). Given an unsigned 32-bit number,
+ returns a (field_number, wire_type) tuple.
+ """
+ return (tag >> TAG_TYPE_BITS), (tag & _TAG_TYPE_MASK)
+
+
+def ZigZagEncode(value):
+ """ZigZag Transform: Encodes signed integers so that they can be
+ effectively used with varint encoding. See wire_format.h for
+ more details.
+ """
+ if value >= 0:
+ return value << 1
+ return (value << 1) ^ (~0)
+
+
+def ZigZagDecode(value):
+ """Inverse of ZigZagEncode()."""
+ if not value & 0x1:
+ return value >> 1
+ return (value >> 1) ^ (~0)
+
+
+
+# The *ByteSize() functions below return the number of bytes required to
+# serialize "field number + type" information and then serialize the value.
+
+
+def Int32ByteSize(field_number, int32):
+ return Int64ByteSize(field_number, int32)
+
+
+def Int64ByteSize(field_number, int64):
+ # Have to convert to uint before calling UInt64ByteSize().
+ return UInt64ByteSize(field_number, 0xffffffffffffffff & int64)
+
+
+def UInt32ByteSize(field_number, uint32):
+ return UInt64ByteSize(field_number, uint32)
+
+
+def UInt64ByteSize(field_number, uint64):
+ return _TagByteSize(field_number) + _VarUInt64ByteSizeNoTag(uint64)
+
+
+def SInt32ByteSize(field_number, int32):
+ return UInt32ByteSize(field_number, ZigZagEncode(int32))
+
+
+def SInt64ByteSize(field_number, int64):
+ return UInt64ByteSize(field_number, ZigZagEncode(int64))
+
+
+def Fixed32ByteSize(field_number, fixed32):
+ return _TagByteSize(field_number) + 4
+
+
+def Fixed64ByteSize(field_number, fixed64):
+ return _TagByteSize(field_number) + 8
+
+
+def SFixed32ByteSize(field_number, sfixed32):
+ return _TagByteSize(field_number) + 4
+
+
+def SFixed64ByteSize(field_number, sfixed64):
+ return _TagByteSize(field_number) + 8
+
+
+def FloatByteSize(field_number, flt):
+ return _TagByteSize(field_number) + 4
+
+
+def DoubleByteSize(field_number, double):
+ return _TagByteSize(field_number) + 8
+
+
+def BoolByteSize(field_number, b):
+ return _TagByteSize(field_number) + 1
+
+
+def EnumByteSize(field_number, enum):
+ return UInt32ByteSize(field_number, enum)
+
+
+def StringByteSize(field_number, string):
+ return BytesByteSize(field_number, string.encode('utf-8'))
+
+
+def BytesByteSize(field_number, b):
+ return (_TagByteSize(field_number)
+ + _VarUInt64ByteSizeNoTag(len(b))
+ + len(b))
+
+
+def GroupByteSize(field_number, message):
+ return (2 * _TagByteSize(field_number) # START and END group.
+ + message.ByteSize())
+
+
+def MessageByteSize(field_number, message):
+ return (_TagByteSize(field_number)
+ + _VarUInt64ByteSizeNoTag(message.ByteSize())
+ + message.ByteSize())
+
+
+def MessageSetItemByteSize(field_number, msg):
+ # First compute the sizes of the tags.
+ # There are 2 tags for the beginning and ending of the repeated group, that
+ # is field number 1, one with field number 2 (type_id) and one with field
+ # number 3 (message).
+ total_size = (2 * _TagByteSize(1) + _TagByteSize(2) + _TagByteSize(3))
+
+ # Add the number of bytes for type_id.
+ total_size += _VarUInt64ByteSizeNoTag(field_number)
+
+ message_size = msg.ByteSize()
+
+ # The number of bytes for encoding the length of the message.
+ total_size += _VarUInt64ByteSizeNoTag(message_size)
+
+ # The size of the message.
+ total_size += message_size
+ return total_size
+
+
+# Private helper functions for the *ByteSize() functions above.
+
+
+def _TagByteSize(field_number):
+ """Returns the bytes required to serialize a tag with this field number."""
+ # Just pass in type 0, since the type won't affect the tag+type size.
+ return _VarUInt64ByteSizeNoTag(PackTag(field_number, 0))
+
+
+def _VarUInt64ByteSizeNoTag(uint64):
+ """Returns the bytes required to serialize a single varint.
+ uint64 must be unsigned.
+ """
+ if uint64 > UINT64_MAX:
+ raise message.EncodeError('Value out of range: %d' % uint64)
+ bytes = 1
+ while uint64 > 0x7f:
+ bytes += 1
+ uint64 >>= 7
+ return bytes