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Diffstat (limited to 'testing/mochitest/pywebsocket/mod_pywebsocket/http_header_util.py')
-rw-r--r-- | testing/mochitest/pywebsocket/mod_pywebsocket/http_header_util.py | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/testing/mochitest/pywebsocket/mod_pywebsocket/http_header_util.py b/testing/mochitest/pywebsocket/mod_pywebsocket/http_header_util.py new file mode 100644 index 000000000..b77465393 --- /dev/null +++ b/testing/mochitest/pywebsocket/mod_pywebsocket/http_header_util.py @@ -0,0 +1,263 @@ +# Copyright 2011, Google Inc. +# All rights reserved. +# +# 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. + + +"""Utilities for parsing and formatting headers that follow the grammar defined +in HTTP RFC http://www.ietf.org/rfc/rfc2616.txt. +""" + + +import urlparse + + +_SEPARATORS = '()<>@,;:\\"/[]?={} \t' + + +def _is_char(c): + """Returns true iff c is in CHAR as specified in HTTP RFC.""" + + return ord(c) <= 127 + + +def _is_ctl(c): + """Returns true iff c is in CTL as specified in HTTP RFC.""" + + return ord(c) <= 31 or ord(c) == 127 + + +class ParsingState(object): + + def __init__(self, data): + self.data = data + self.head = 0 + + +def peek(state, pos=0): + """Peeks the character at pos from the head of data.""" + + if state.head + pos >= len(state.data): + return None + + return state.data[state.head + pos] + + +def consume(state, amount=1): + """Consumes specified amount of bytes from the head and returns the + consumed bytes. If there's not enough bytes to consume, returns None. + """ + + if state.head + amount > len(state.data): + return None + + result = state.data[state.head:state.head + amount] + state.head = state.head + amount + return result + + +def consume_string(state, expected): + """Given a parsing state and a expected string, consumes the string from + the head. Returns True if consumed successfully. Otherwise, returns + False. + """ + + pos = 0 + + for c in expected: + if c != peek(state, pos): + return False + pos += 1 + + consume(state, pos) + return True + + +def consume_lws(state): + """Consumes a LWS from the head. Returns True if any LWS is consumed. + Otherwise, returns False. + + LWS = [CRLF] 1*( SP | HT ) + """ + + original_head = state.head + + consume_string(state, '\r\n') + + pos = 0 + + while True: + c = peek(state, pos) + if c == ' ' or c == '\t': + pos += 1 + else: + if pos == 0: + state.head = original_head + return False + else: + consume(state, pos) + return True + + +def consume_lwses(state): + """Consumes *LWS from the head.""" + + while consume_lws(state): + pass + + +def consume_token(state): + """Consumes a token from the head. Returns the token or None if no token + was found. + """ + + pos = 0 + + while True: + c = peek(state, pos) + if c is None or c in _SEPARATORS or _is_ctl(c) or not _is_char(c): + if pos == 0: + return None + + return consume(state, pos) + else: + pos += 1 + + +def consume_token_or_quoted_string(state): + """Consumes a token or a quoted-string, and returns the token or unquoted + string. If no token or quoted-string was found, returns None. + """ + + original_head = state.head + + if not consume_string(state, '"'): + return consume_token(state) + + result = [] + + expect_quoted_pair = False + + while True: + if not expect_quoted_pair and consume_lws(state): + result.append(' ') + continue + + c = consume(state) + if c is None: + # quoted-string is not enclosed with double quotation + state.head = original_head + return None + elif expect_quoted_pair: + expect_quoted_pair = False + if _is_char(c): + result.append(c) + else: + # Non CHAR character found in quoted-pair + state.head = original_head + return None + elif c == '\\': + expect_quoted_pair = True + elif c == '"': + return ''.join(result) + elif _is_ctl(c): + # Invalid character %r found in qdtext + state.head = original_head + return None + else: + result.append(c) + + +def quote_if_necessary(s): + """Quotes arbitrary string into quoted-string.""" + + quote = False + if s == '': + return '""' + + result = [] + for c in s: + if c == '"' or c in _SEPARATORS or _is_ctl(c) or not _is_char(c): + quote = True + + if c == '"' or _is_ctl(c): + result.append('\\' + c) + else: + result.append(c) + + if quote: + return '"' + ''.join(result) + '"' + else: + return ''.join(result) + + +def parse_uri(uri): + """Parse absolute URI then return host, port and resource.""" + + parsed = urlparse.urlsplit(uri) + if parsed.scheme != 'wss' and parsed.scheme != 'ws': + # |uri| must be a relative URI. + # TODO(toyoshim): Should validate |uri|. + return None, None, uri + + if parsed.hostname is None: + return None, None, None + + port = None + try: + port = parsed.port + except ValueError, e: + # port property cause ValueError on invalid null port description like + # 'ws://host:/path'. + return None, None, None + + if port is None: + if parsed.scheme == 'ws': + port = 80 + else: + port = 443 + + path = parsed.path + if not path: + path += '/' + if parsed.query: + path += '?' + parsed.query + if parsed.fragment: + path += '#' + parsed.fragment + + return parsed.hostname, port, path + + +try: + urlparse.uses_netloc.index('ws') +except ValueError, e: + # urlparse in Python2.5.1 doesn't have 'ws' and 'wss' entries. + urlparse.uses_netloc.append('ws') + urlparse.uses_netloc.append('wss') + + +# vi:sts=4 sw=4 et |