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##############################################################################
#
# Copyright (c) 2001, 2002 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Data Chunk Receiver
"""
from waitress.rfc7230 import CHUNK_EXT_RE, ONLY_HEXDIG_RE
from waitress.utilities import BadRequest, find_double_newline
class FixedStreamReceiver:
# See IStreamConsumer
completed = False
error = None
def __init__(self, cl, buf):
self.remain = cl
self.buf = buf
def __len__(self):
return self.buf.__len__()
def received(self, data):
"See IStreamConsumer"
rm = self.remain
if rm < 1:
self.completed = True # Avoid any chance of spinning
return 0
datalen = len(data)
if rm <= datalen:
self.buf.append(data[:rm])
self.remain = 0
self.completed = True
return rm
else:
self.buf.append(data)
self.remain -= datalen
return datalen
def getfile(self):
return self.buf.getfile()
def getbuf(self):
return self.buf
class ChunkedReceiver:
chunk_remainder = 0
validate_chunk_end = False
control_line = b""
chunk_end = b""
all_chunks_received = False
trailer = b""
completed = False
error = None
# max_control_line = 1024
# max_trailer = 65536
def __init__(self, buf):
self.buf = buf
def __len__(self):
return self.buf.__len__()
def received(self, s):
# Returns the number of bytes consumed.
if self.completed:
return 0
orig_size = len(s)
while s:
rm = self.chunk_remainder
if rm > 0:
# Receive the remainder of a chunk.
to_write = s[:rm]
self.buf.append(to_write)
written = len(to_write)
s = s[written:]
self.chunk_remainder -= written
if self.chunk_remainder == 0:
self.validate_chunk_end = True
elif self.validate_chunk_end:
s = self.chunk_end + s
pos = s.find(b"\r\n")
if pos < 0 and len(s) < 2:
self.chunk_end = s
s = b""
else:
self.chunk_end = b""
if pos == 0:
# Chop off the terminating CR LF from the chunk
s = s[2:]
else:
self.error = BadRequest("Chunk not properly terminated")
self.all_chunks_received = True
# Always exit this loop
self.validate_chunk_end = False
elif not self.all_chunks_received:
# Receive a control line.
s = self.control_line + s
pos = s.find(b"\r\n")
if pos < 0:
# Control line not finished.
self.control_line = s
s = b""
else:
# Control line finished.
line = s[:pos]
s = s[pos + 2 :]
self.control_line = b""
if line:
# Begin a new chunk.
semi = line.find(b";")
if semi >= 0:
extinfo = line[semi:]
valid_ext_info = CHUNK_EXT_RE.match(extinfo)
if not valid_ext_info:
self.error = BadRequest("Invalid chunk extension")
self.all_chunks_received = True
break
line = line[:semi]
if not ONLY_HEXDIG_RE.match(line):
self.error = BadRequest("Invalid chunk size")
self.all_chunks_received = True
break
# Can not fail due to matching against the regular
# expression above
sz = int(line, 16) # hexadecimal
if sz > 0:
# Start a new chunk.
self.chunk_remainder = sz
else:
# Finished chunks.
self.all_chunks_received = True
# else expect a control line.
else:
# Receive the trailer.
trailer = self.trailer + s
if trailer.startswith(b"\r\n"):
# No trailer.
self.completed = True
return orig_size - (len(trailer) - 2)
pos = find_double_newline(trailer)
if pos < 0:
# Trailer not finished.
self.trailer = trailer
s = b""
else:
# Finished the trailer.
self.completed = True
self.trailer = trailer[:pos]
return orig_size - (len(trailer) - pos)
return orig_size
def getfile(self):
return self.buf.getfile()
def getbuf(self):
return self.buf
|
