1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/testing/mochitest/pywebsocket/mod_pywebsocket/util.py Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,496 @@
1.4 +# Copyright 2011, Google Inc.
1.5 +# All rights reserved.
1.6 +#
1.7 +# Redistribution and use in source and binary forms, with or without
1.8 +# modification, are permitted provided that the following conditions are
1.9 +# met:
1.10 +#
1.11 +# * Redistributions of source code must retain the above copyright
1.12 +# notice, this list of conditions and the following disclaimer.
1.13 +# * Redistributions in binary form must reproduce the above
1.14 +# copyright notice, this list of conditions and the following disclaimer
1.15 +# in the documentation and/or other materials provided with the
1.16 +# distribution.
1.17 +# * Neither the name of Google Inc. nor the names of its
1.18 +# contributors may be used to endorse or promote products derived from
1.19 +# this software without specific prior written permission.
1.20 +#
1.21 +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.22 +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.23 +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1.24 +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1.25 +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1.26 +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1.27 +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1.28 +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1.29 +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.30 +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1.31 +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.32 +
1.33 +
1.34 +"""WebSocket utilities.
1.35 +"""
1.36 +
1.37 +
1.38 +import array
1.39 +import errno
1.40 +
1.41 +# Import hash classes from a module available and recommended for each Python
1.42 +# version and re-export those symbol. Use sha and md5 module in Python 2.4, and
1.43 +# hashlib module in Python 2.6.
1.44 +try:
1.45 + import hashlib
1.46 + md5_hash = hashlib.md5
1.47 + sha1_hash = hashlib.sha1
1.48 +except ImportError:
1.49 + import md5
1.50 + import sha
1.51 + md5_hash = md5.md5
1.52 + sha1_hash = sha.sha
1.53 +
1.54 +import StringIO
1.55 +import logging
1.56 +import os
1.57 +import re
1.58 +import socket
1.59 +import traceback
1.60 +import zlib
1.61 +
1.62 +
1.63 +def get_stack_trace():
1.64 + """Get the current stack trace as string.
1.65 +
1.66 + This is needed to support Python 2.3.
1.67 + TODO: Remove this when we only support Python 2.4 and above.
1.68 + Use traceback.format_exc instead.
1.69 + """
1.70 +
1.71 + out = StringIO.StringIO()
1.72 + traceback.print_exc(file=out)
1.73 + return out.getvalue()
1.74 +
1.75 +
1.76 +def prepend_message_to_exception(message, exc):
1.77 + """Prepend message to the exception."""
1.78 +
1.79 + exc.args = (message + str(exc),)
1.80 + return
1.81 +
1.82 +
1.83 +def __translate_interp(interp, cygwin_path):
1.84 + """Translate interp program path for Win32 python to run cygwin program
1.85 + (e.g. perl). Note that it doesn't support path that contains space,
1.86 + which is typically true for Unix, where #!-script is written.
1.87 + For Win32 python, cygwin_path is a directory of cygwin binaries.
1.88 +
1.89 + Args:
1.90 + interp: interp command line
1.91 + cygwin_path: directory name of cygwin binary, or None
1.92 + Returns:
1.93 + translated interp command line.
1.94 + """
1.95 + if not cygwin_path:
1.96 + return interp
1.97 + m = re.match('^[^ ]*/([^ ]+)( .*)?', interp)
1.98 + if m:
1.99 + cmd = os.path.join(cygwin_path, m.group(1))
1.100 + return cmd + m.group(2)
1.101 + return interp
1.102 +
1.103 +
1.104 +def get_script_interp(script_path, cygwin_path=None):
1.105 + """Gets #!-interpreter command line from the script.
1.106 +
1.107 + It also fixes command path. When Cygwin Python is used, e.g. in WebKit,
1.108 + it could run "/usr/bin/perl -wT hello.pl".
1.109 + When Win32 Python is used, e.g. in Chromium, it couldn't. So, fix
1.110 + "/usr/bin/perl" to "<cygwin_path>\perl.exe".
1.111 +
1.112 + Args:
1.113 + script_path: pathname of the script
1.114 + cygwin_path: directory name of cygwin binary, or None
1.115 + Returns:
1.116 + #!-interpreter command line, or None if it is not #!-script.
1.117 + """
1.118 + fp = open(script_path)
1.119 + line = fp.readline()
1.120 + fp.close()
1.121 + m = re.match('^#!(.*)', line)
1.122 + if m:
1.123 + return __translate_interp(m.group(1), cygwin_path)
1.124 + return None
1.125 +
1.126 +
1.127 +def wrap_popen3_for_win(cygwin_path):
1.128 + """Wrap popen3 to support #!-script on Windows.
1.129 +
1.130 + Args:
1.131 + cygwin_path: path for cygwin binary if command path is needed to be
1.132 + translated. None if no translation required.
1.133 + """
1.134 +
1.135 + __orig_popen3 = os.popen3
1.136 +
1.137 + def __wrap_popen3(cmd, mode='t', bufsize=-1):
1.138 + cmdline = cmd.split(' ')
1.139 + interp = get_script_interp(cmdline[0], cygwin_path)
1.140 + if interp:
1.141 + cmd = interp + ' ' + cmd
1.142 + return __orig_popen3(cmd, mode, bufsize)
1.143 +
1.144 + os.popen3 = __wrap_popen3
1.145 +
1.146 +
1.147 +def hexify(s):
1.148 + return ' '.join(map(lambda x: '%02x' % ord(x), s))
1.149 +
1.150 +
1.151 +def get_class_logger(o):
1.152 + return logging.getLogger(
1.153 + '%s.%s' % (o.__class__.__module__, o.__class__.__name__))
1.154 +
1.155 +
1.156 +class NoopMasker(object):
1.157 + """A masking object that has the same interface as RepeatedXorMasker but
1.158 + just returns the string passed in without making any change.
1.159 + """
1.160 +
1.161 + def __init__(self):
1.162 + pass
1.163 +
1.164 + def mask(self, s):
1.165 + return s
1.166 +
1.167 +
1.168 +class RepeatedXorMasker(object):
1.169 + """A masking object that applies XOR on the string given to mask method
1.170 + with the masking bytes given to the constructor repeatedly. This object
1.171 + remembers the position in the masking bytes the last mask method call
1.172 + ended and resumes from that point on the next mask method call.
1.173 + """
1.174 +
1.175 + def __init__(self, mask):
1.176 + self._mask = map(ord, mask)
1.177 + self._mask_size = len(self._mask)
1.178 + self._count = 0
1.179 +
1.180 + def mask(self, s):
1.181 + result = array.array('B')
1.182 + result.fromstring(s)
1.183 + # Use temporary local variables to eliminate the cost to access
1.184 + # attributes
1.185 + count = self._count
1.186 + mask = self._mask
1.187 + mask_size = self._mask_size
1.188 + for i in xrange(len(result)):
1.189 + result[i] ^= mask[count]
1.190 + count = (count + 1) % mask_size
1.191 + self._count = count
1.192 +
1.193 + return result.tostring()
1.194 +
1.195 +
1.196 +class DeflateRequest(object):
1.197 + """A wrapper class for request object to intercept send and recv to perform
1.198 + deflate compression and decompression transparently.
1.199 + """
1.200 +
1.201 + def __init__(self, request):
1.202 + self._request = request
1.203 + self.connection = DeflateConnection(request.connection)
1.204 +
1.205 + def __getattribute__(self, name):
1.206 + if name in ('_request', 'connection'):
1.207 + return object.__getattribute__(self, name)
1.208 + return self._request.__getattribute__(name)
1.209 +
1.210 + def __setattr__(self, name, value):
1.211 + if name in ('_request', 'connection'):
1.212 + return object.__setattr__(self, name, value)
1.213 + return self._request.__setattr__(name, value)
1.214 +
1.215 +
1.216 +# By making wbits option negative, we can suppress CMF/FLG (2 octet) and
1.217 +# ADLER32 (4 octet) fields of zlib so that we can use zlib module just as
1.218 +# deflate library. DICTID won't be added as far as we don't set dictionary.
1.219 +# LZ77 window of 32K will be used for both compression and decompression.
1.220 +# For decompression, we can just use 32K to cover any windows size. For
1.221 +# compression, we use 32K so receivers must use 32K.
1.222 +#
1.223 +# Compression level is Z_DEFAULT_COMPRESSION. We don't have to match level
1.224 +# to decode.
1.225 +#
1.226 +# See zconf.h, deflate.cc, inflate.cc of zlib library, and zlibmodule.c of
1.227 +# Python. See also RFC1950 (ZLIB 3.3).
1.228 +
1.229 +
1.230 +class _Deflater(object):
1.231 +
1.232 + def __init__(self, window_bits):
1.233 + self._logger = get_class_logger(self)
1.234 +
1.235 + self._compress = zlib.compressobj(
1.236 + zlib.Z_DEFAULT_COMPRESSION, zlib.DEFLATED, -window_bits)
1.237 +
1.238 + def compress_and_flush(self, bytes):
1.239 + compressed_bytes = self._compress.compress(bytes)
1.240 + compressed_bytes += self._compress.flush(zlib.Z_SYNC_FLUSH)
1.241 + self._logger.debug('Compress input %r', bytes)
1.242 + self._logger.debug('Compress result %r', compressed_bytes)
1.243 + return compressed_bytes
1.244 +
1.245 +
1.246 +class _Inflater(object):
1.247 +
1.248 + def __init__(self):
1.249 + self._logger = get_class_logger(self)
1.250 +
1.251 + self._unconsumed = ''
1.252 +
1.253 + self.reset()
1.254 +
1.255 + def decompress(self, size):
1.256 + if not (size == -1 or size > 0):
1.257 + raise Exception('size must be -1 or positive')
1.258 +
1.259 + data = ''
1.260 +
1.261 + while True:
1.262 + if size == -1:
1.263 + data += self._decompress.decompress(self._unconsumed)
1.264 + # See Python bug http://bugs.python.org/issue12050 to
1.265 + # understand why the same code cannot be used for updating
1.266 + # self._unconsumed for here and else block.
1.267 + self._unconsumed = ''
1.268 + else:
1.269 + data += self._decompress.decompress(
1.270 + self._unconsumed, size - len(data))
1.271 + self._unconsumed = self._decompress.unconsumed_tail
1.272 + if self._decompress.unused_data:
1.273 + # Encountered a last block (i.e. a block with BFINAL = 1) and
1.274 + # found a new stream (unused_data). We cannot use the same
1.275 + # zlib.Decompress object for the new stream. Create a new
1.276 + # Decompress object to decompress the new one.
1.277 + #
1.278 + # It's fine to ignore unconsumed_tail if unused_data is not
1.279 + # empty.
1.280 + self._unconsumed = self._decompress.unused_data
1.281 + self.reset()
1.282 + if size >= 0 and len(data) == size:
1.283 + # data is filled. Don't call decompress again.
1.284 + break
1.285 + else:
1.286 + # Re-invoke Decompress.decompress to try to decompress all
1.287 + # available bytes before invoking read which blocks until
1.288 + # any new byte is available.
1.289 + continue
1.290 + else:
1.291 + # Here, since unused_data is empty, even if unconsumed_tail is
1.292 + # not empty, bytes of requested length are already in data. We
1.293 + # don't have to "continue" here.
1.294 + break
1.295 +
1.296 + if data:
1.297 + self._logger.debug('Decompressed %r', data)
1.298 + return data
1.299 +
1.300 + def append(self, data):
1.301 + self._logger.debug('Appended %r', data)
1.302 + self._unconsumed += data
1.303 +
1.304 + def reset(self):
1.305 + self._logger.debug('Reset')
1.306 + self._decompress = zlib.decompressobj(-zlib.MAX_WBITS)
1.307 +
1.308 +
1.309 +# Compresses/decompresses given octets using the method introduced in RFC1979.
1.310 +
1.311 +
1.312 +class _RFC1979Deflater(object):
1.313 + """A compressor class that applies DEFLATE to given byte sequence and
1.314 + flushes using the algorithm described in the RFC1979 section 2.1.
1.315 + """
1.316 +
1.317 + def __init__(self, window_bits, no_context_takeover):
1.318 + self._deflater = None
1.319 + if window_bits is None:
1.320 + window_bits = zlib.MAX_WBITS
1.321 + self._window_bits = window_bits
1.322 + self._no_context_takeover = no_context_takeover
1.323 +
1.324 + def filter(self, bytes):
1.325 + if self._deflater is None or self._no_context_takeover:
1.326 + self._deflater = _Deflater(self._window_bits)
1.327 +
1.328 + # Strip last 4 octets which is LEN and NLEN field of a non-compressed
1.329 + # block added for Z_SYNC_FLUSH.
1.330 + return self._deflater.compress_and_flush(bytes)[:-4]
1.331 +
1.332 +
1.333 +class _RFC1979Inflater(object):
1.334 + """A decompressor class for byte sequence compressed and flushed following
1.335 + the algorithm described in the RFC1979 section 2.1.
1.336 + """
1.337 +
1.338 + def __init__(self):
1.339 + self._inflater = _Inflater()
1.340 +
1.341 + def filter(self, bytes):
1.342 + # Restore stripped LEN and NLEN field of a non-compressed block added
1.343 + # for Z_SYNC_FLUSH.
1.344 + self._inflater.append(bytes + '\x00\x00\xff\xff')
1.345 + return self._inflater.decompress(-1)
1.346 +
1.347 +
1.348 +class DeflateSocket(object):
1.349 + """A wrapper class for socket object to intercept send and recv to perform
1.350 + deflate compression and decompression transparently.
1.351 + """
1.352 +
1.353 + # Size of the buffer passed to recv to receive compressed data.
1.354 + _RECV_SIZE = 4096
1.355 +
1.356 + def __init__(self, socket):
1.357 + self._socket = socket
1.358 +
1.359 + self._logger = get_class_logger(self)
1.360 +
1.361 + self._deflater = _Deflater(zlib.MAX_WBITS)
1.362 + self._inflater = _Inflater()
1.363 +
1.364 + def recv(self, size):
1.365 + """Receives data from the socket specified on the construction up
1.366 + to the specified size. Once any data is available, returns it even
1.367 + if it's smaller than the specified size.
1.368 + """
1.369 +
1.370 + # TODO(tyoshino): Allow call with size=0. It should block until any
1.371 + # decompressed data is available.
1.372 + if size <= 0:
1.373 + raise Exception('Non-positive size passed')
1.374 + while True:
1.375 + data = self._inflater.decompress(size)
1.376 + if len(data) != 0:
1.377 + return data
1.378 +
1.379 + read_data = self._socket.recv(DeflateSocket._RECV_SIZE)
1.380 + if not read_data:
1.381 + return ''
1.382 + self._inflater.append(read_data)
1.383 +
1.384 + def sendall(self, bytes):
1.385 + self.send(bytes)
1.386 +
1.387 + def send(self, bytes):
1.388 + self._socket.sendall(self._deflater.compress_and_flush(bytes))
1.389 + return len(bytes)
1.390 +
1.391 +
1.392 +class DeflateConnection(object):
1.393 + """A wrapper class for request object to intercept write and read to
1.394 + perform deflate compression and decompression transparently.
1.395 + """
1.396 +
1.397 + def __init__(self, connection):
1.398 + self._connection = connection
1.399 +
1.400 + self._logger = get_class_logger(self)
1.401 +
1.402 + self._deflater = _Deflater(zlib.MAX_WBITS)
1.403 + self._inflater = _Inflater()
1.404 +
1.405 + def get_remote_addr(self):
1.406 + return self._connection.remote_addr
1.407 + remote_addr = property(get_remote_addr)
1.408 +
1.409 + def put_bytes(self, bytes):
1.410 + self.write(bytes)
1.411 +
1.412 + def read(self, size=-1):
1.413 + """Reads at most size bytes. Blocks until there's at least one byte
1.414 + available.
1.415 + """
1.416 +
1.417 + # TODO(tyoshino): Allow call with size=0.
1.418 + if not (size == -1 or size > 0):
1.419 + raise Exception('size must be -1 or positive')
1.420 +
1.421 + data = ''
1.422 + while True:
1.423 + if size == -1:
1.424 + data += self._inflater.decompress(-1)
1.425 + else:
1.426 + data += self._inflater.decompress(size - len(data))
1.427 +
1.428 + if size >= 0 and len(data) != 0:
1.429 + break
1.430 +
1.431 + # TODO(tyoshino): Make this read efficient by some workaround.
1.432 + #
1.433 + # In 3.0.3 and prior of mod_python, read blocks until length bytes
1.434 + # was read. We don't know the exact size to read while using
1.435 + # deflate, so read byte-by-byte.
1.436 + #
1.437 + # _StandaloneRequest.read that ultimately performs
1.438 + # socket._fileobject.read also blocks until length bytes was read
1.439 + read_data = self._connection.read(1)
1.440 + if not read_data:
1.441 + break
1.442 + self._inflater.append(read_data)
1.443 + return data
1.444 +
1.445 + def write(self, bytes):
1.446 + self._connection.write(self._deflater.compress_and_flush(bytes))
1.447 +
1.448 +
1.449 +def _is_ewouldblock_errno(error_number):
1.450 + """Returns True iff error_number indicates that receive operation would
1.451 + block. To make this portable, we check availability of errno and then
1.452 + compare them.
1.453 + """
1.454 +
1.455 + for error_name in ['WSAEWOULDBLOCK', 'EWOULDBLOCK', 'EAGAIN']:
1.456 + if (error_name in dir(errno) and
1.457 + error_number == getattr(errno, error_name)):
1.458 + return True
1.459 + return False
1.460 +
1.461 +
1.462 +def drain_received_data(raw_socket):
1.463 + # Set the socket non-blocking.
1.464 + original_timeout = raw_socket.gettimeout()
1.465 + raw_socket.settimeout(0.0)
1.466 +
1.467 + drained_data = []
1.468 +
1.469 + # Drain until the socket is closed or no data is immediately
1.470 + # available for read.
1.471 + while True:
1.472 + try:
1.473 + data = raw_socket.recv(1)
1.474 + if not data:
1.475 + break
1.476 + drained_data.append(data)
1.477 + except socket.error, e:
1.478 + # e can be either a pair (errno, string) or just a string (or
1.479 + # something else) telling what went wrong. We suppress only
1.480 + # the errors that indicates that the socket blocks. Those
1.481 + # exceptions can be parsed as a pair (errno, string).
1.482 + try:
1.483 + error_number, message = e
1.484 + except:
1.485 + # Failed to parse socket.error.
1.486 + raise e
1.487 +
1.488 + if _is_ewouldblock_errno(error_number):
1.489 + break
1.490 + else:
1.491 + raise e
1.492 +
1.493 + # Rollback timeout value.
1.494 + raw_socket.settimeout(original_timeout)
1.495 +
1.496 + return ''.join(drained_data)
1.497 +
1.498 +
1.499 +# vi:sts=4 sw=4 et
