mirror of
https://gerrit.googlesource.com/git-repo
synced 2024-12-23 07:16:21 +00:00
126 lines
4.8 KiB
Python
126 lines
4.8 KiB
Python
# 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.
|
|
|
|
"""OutputStream is the primitive interface for sticking bits on the wire.
|
|
|
|
All protocol buffer serialization can be expressed in terms of
|
|
the OutputStream primitives provided here.
|
|
"""
|
|
|
|
__author__ = 'robinson@google.com (Will Robinson)'
|
|
|
|
import array
|
|
import struct
|
|
from froofle.protobuf import message
|
|
from froofle.protobuf.internal import wire_format
|
|
|
|
|
|
|
|
# Note that much of this code is ported from //net/proto/ProtocolBuffer, and
|
|
# that the interface is strongly inspired by CodedOutputStream from the C++
|
|
# proto2 implementation.
|
|
|
|
|
|
class OutputStream(object):
|
|
|
|
"""Contains all logic for writing bits, and ToString() to get the result."""
|
|
|
|
def __init__(self):
|
|
self._buffer = array.array('B')
|
|
|
|
def AppendRawBytes(self, raw_bytes):
|
|
"""Appends raw_bytes to our internal buffer."""
|
|
self._buffer.fromstring(raw_bytes)
|
|
|
|
def AppendLittleEndian32(self, unsigned_value):
|
|
"""Appends an unsigned 32-bit integer to the internal buffer,
|
|
in little-endian byte order.
|
|
"""
|
|
if not 0 <= unsigned_value <= wire_format.UINT32_MAX:
|
|
raise message.EncodeError(
|
|
'Unsigned 32-bit out of range: %d' % unsigned_value)
|
|
self._buffer.fromstring(struct.pack(
|
|
wire_format.FORMAT_UINT32_LITTLE_ENDIAN, unsigned_value))
|
|
|
|
def AppendLittleEndian64(self, unsigned_value):
|
|
"""Appends an unsigned 64-bit integer to the internal buffer,
|
|
in little-endian byte order.
|
|
"""
|
|
if not 0 <= unsigned_value <= wire_format.UINT64_MAX:
|
|
raise message.EncodeError(
|
|
'Unsigned 64-bit out of range: %d' % unsigned_value)
|
|
self._buffer.fromstring(struct.pack(
|
|
wire_format.FORMAT_UINT64_LITTLE_ENDIAN, unsigned_value))
|
|
|
|
def AppendVarint32(self, value):
|
|
"""Appends a signed 32-bit integer to the internal buffer,
|
|
encoded as a varint. (Note that a negative varint32 will
|
|
always require 10 bytes of space.)
|
|
"""
|
|
if not wire_format.INT32_MIN <= value <= wire_format.INT32_MAX:
|
|
raise message.EncodeError('Value out of range: %d' % value)
|
|
self.AppendVarint64(value)
|
|
|
|
def AppendVarUInt32(self, value):
|
|
"""Appends an unsigned 32-bit integer to the internal buffer,
|
|
encoded as a varint.
|
|
"""
|
|
if not 0 <= value <= wire_format.UINT32_MAX:
|
|
raise message.EncodeError('Value out of range: %d' % value)
|
|
self.AppendVarUInt64(value)
|
|
|
|
def AppendVarint64(self, value):
|
|
"""Appends a signed 64-bit integer to the internal buffer,
|
|
encoded as a varint.
|
|
"""
|
|
if not wire_format.INT64_MIN <= value <= wire_format.INT64_MAX:
|
|
raise message.EncodeError('Value out of range: %d' % value)
|
|
if value < 0:
|
|
value += (1 << 64)
|
|
self.AppendVarUInt64(value)
|
|
|
|
def AppendVarUInt64(self, unsigned_value):
|
|
"""Appends an unsigned 64-bit integer to the internal buffer,
|
|
encoded as a varint.
|
|
"""
|
|
if not 0 <= unsigned_value <= wire_format.UINT64_MAX:
|
|
raise message.EncodeError('Value out of range: %d' % unsigned_value)
|
|
while True:
|
|
bits = unsigned_value & 0x7f
|
|
unsigned_value >>= 7
|
|
if not unsigned_value:
|
|
self._buffer.append(bits)
|
|
break
|
|
self._buffer.append(0x80|bits)
|
|
|
|
def ToString(self):
|
|
"""Returns a string containing the bytes in our internal buffer."""
|
|
return self._buffer.tostring()
|