diff options
Diffstat (limited to 'third_party')
| -rw-r--r-- | third_party/__init__.py | 0 | ||||
| -rw-r--r-- | third_party/ipaddr.py | 1951 | ||||
| -rw-r--r-- | third_party/ply/__init__.py | 4 | ||||
| -rw-r--r-- | third_party/ply/lex.py | 1058 | ||||
| -rw-r--r-- | third_party/ply/yacc.py | 3276 |
5 files changed, 6289 insertions, 0 deletions
diff --git a/third_party/__init__.py b/third_party/__init__.py new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/third_party/__init__.py diff --git a/third_party/ipaddr.py b/third_party/ipaddr.py new file mode 100644 index 0000000..f4060f6 --- /dev/null +++ b/third_party/ipaddr.py @@ -0,0 +1,1951 @@ +#!/usr/bin/python +# +# Copyright 2007 Google Inc. +# Licensed to PSF under a Contributor Agreement. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or +# implied. See the License for the specific language governing +# permissions and limitations under the License. + +"""A fast, lightweight IPv4/IPv6 manipulation library in Python. + +This library is used to create/poke/manipulate IPv4 and IPv6 addresses +and networks. + +""" + +__version__ = '2.1.7' + +import struct + +IPV4LENGTH = 32 +IPV6LENGTH = 128 + + +class AddressValueError(ValueError): + """A Value Error related to the address.""" + + +class NetmaskValueError(ValueError): + """A Value Error related to the netmask.""" + + +def IPAddress(address, version=None): + """Take an IP string/int and return an object of the correct type. + + Args: + address: A string or integer, the IP address. Either IPv4 or + IPv6 addresses may be supplied; integers less than 2**32 will + be considered to be IPv4 by default. + version: An Integer, 4 or 6. If set, don't try to automatically + determine what the IP address type is. important for things + like IPAddress(1), which could be IPv4, '0.0.0.1', or IPv6, + '::1'. + + Returns: + An IPv4Address or IPv6Address object. + + Raises: + ValueError: if the string passed isn't either a v4 or a v6 + address. + + """ + if version: + if version == 4: + return IPv4Address(address) + elif version == 6: + return IPv6Address(address) + + try: + return IPv4Address(address) + except (AddressValueError, NetmaskValueError): + pass + + try: + return IPv6Address(address) + except (AddressValueError, NetmaskValueError): + pass + + raise ValueError('%r does not appear to be an IPv4 or IPv6 address' % + address) + + +def IPNetwork(address, version=None, strict=False): + """Take an IP string/int and return an object of the correct type. + + Args: + address: A string or integer, the IP address. Either IPv4 or + IPv6 addresses may be supplied; integers less than 2**32 will + be considered to be IPv4 by default. + version: An Integer, if set, don't try to automatically + determine what the IP address type is. important for things + like IPNetwork(1), which could be IPv4, '0.0.0.1/32', or IPv6, + '::1/128'. + + Returns: + An IPv4Network or IPv6Network object. + + Raises: + ValueError: if the string passed isn't either a v4 or a v6 + address. Or if a strict network was requested and a strict + network wasn't given. + + """ + if version: + if version == 4: + return IPv4Network(address, strict) + elif version == 6: + return IPv6Network(address, strict) + + try: + return IPv4Network(address, strict) + except (AddressValueError, NetmaskValueError): + pass + + try: + return IPv6Network(address, strict) + except (AddressValueError, NetmaskValueError): + pass + + raise ValueError('%r does not appear to be an IPv4 or IPv6 network' % + address) + + +def v4_int_to_packed(address): + """The binary representation of this address. + + Args: + address: An integer representation of an IPv4 IP address. + + Returns: + The binary representation of this address. + + Raises: + ValueError: If the integer is too large to be an IPv4 IP + address. + """ + if address > _BaseV4._ALL_ONES: + raise ValueError('Address too large for IPv4') + return struct.pack('!I', address) + + +def v6_int_to_packed(address): + """The binary representation of this address. + + Args: + address: An integer representation of an IPv4 IP address. + + Returns: + The binary representation of this address. + """ + return struct.pack('!QQ', address >> 64, address & (2**64 - 1)) + + +def _find_address_range(addresses): + """Find a sequence of addresses. + + Args: + addresses: a list of IPv4 or IPv6 addresses. + + Returns: + A tuple containing the first and last IP addresses in the sequence. + + """ + first = last = addresses[0] + for ip in addresses[1:]: + if ip._ip == last._ip + 1: + last = ip + else: + break + return (first, last) + +def _get_prefix_length(number1, number2, bits): + """Get the number of leading bits that are same for two numbers. + + Args: + number1: an integer. + number2: another integer. + bits: the maximum number of bits to compare. + + Returns: + The number of leading bits that are the same for two numbers. + + """ + for i in range(bits): + if number1 >> i == number2 >> i: + return bits - i + return 0 + +def _count_righthand_zero_bits(number, bits): + """Count the number of zero bits on the right hand side. + + Args: + number: an integer. + bits: maximum number of bits to count. + + Returns: + The number of zero bits on the right hand side of the number. + + """ + if number == 0: + return bits + for i in range(bits): + if (number >> i) % 2: + return i + +def summarize_address_range(first, last): + """Summarize a network range given the first and last IP addresses. + + Example: + >>> summarize_address_range(IPv4Address('1.1.1.0'), + IPv4Address('1.1.1.130')) + [IPv4Network('1.1.1.0/25'), IPv4Network('1.1.1.128/31'), + IPv4Network('1.1.1.130/32')] + + Args: + first: the first IPv4Address or IPv6Address in the range. + last: the last IPv4Address or IPv6Address in the range. + + Returns: + The address range collapsed to a list of IPv4Network's or + IPv6Network's. + + Raise: + TypeError: + If the first and last objects are not IP addresses. + If the first and last objects are not the same version. + ValueError: + If the last object is not greater than the first. + If the version is not 4 or 6. + + """ + if not (isinstance(first, _BaseIP) and isinstance(last, _BaseIP)): + raise TypeError('first and last must be IP addresses, not networks') + if first.version != last.version: + raise TypeError("%s and %s are not of the same version" % ( + str(self), str(other))) + if first > last: + raise ValueError('last IP address must be greater than first') + + networks = [] + + if first.version == 4: + ip = IPv4Network + elif first.version == 6: + ip = IPv6Network + else: + raise ValueError('unknown IP version') + + ip_bits = first._max_prefixlen + first_int = first._ip + last_int = last._ip + while first_int <= last_int: + nbits = _count_righthand_zero_bits(first_int, ip_bits) + current = None + while nbits >= 0: + addend = 2**nbits - 1 + current = first_int + addend + nbits -= 1 + if current <= last_int: + break + prefix = _get_prefix_length(first_int, current, ip_bits) + net = ip('%s/%d' % (str(first), prefix)) + networks.append(net) + if current == ip._ALL_ONES: + break + first_int = current + 1 + first = IPAddress(first_int, version=first._version) + return networks + +def _collapse_address_list_recursive(addresses): + """Loops through the addresses, collapsing concurrent netblocks. + + Example: + + ip1 = IPv4Network'1.1.0.0/24') + ip2 = IPv4Network'1.1.1.0/24') + ip3 = IPv4Network'1.1.2.0/24') + ip4 = IPv4Network'1.1.3.0/24') + ip5 = IPv4Network'1.1.4.0/24') + ip6 = IPv4Network'1.1.0.1/22') + + _collapse_address_list_recursive([ip1, ip2, ip3, ip4, ip5, ip6]) -> + [IPv4Network('1.1.0.0/22'), IPv4Network('1.1.4.0/24')] + + This shouldn't be called directly; it is called via + collapse_address_list([]). + + Args: + addresses: A list of IPv4Network's or IPv6Network's + + Returns: + A list of IPv4Network's or IPv6Network's depending on what we were + passed. + + """ + ret_array = [] + optimized = False + + for cur_addr in addresses: + if not ret_array: + ret_array.append(cur_addr) + continue + if cur_addr in ret_array[-1]: + optimized = True + elif cur_addr == ret_array[-1].supernet().subnet()[1]: + ret_array.append(ret_array.pop().supernet()) + optimized = True + else: + ret_array.append(cur_addr) + + if optimized: + return _collapse_address_list_recursive(ret_array) + + return ret_array + + +def collapse_address_list(addresses): + """Collapse a list of IP objects. + + Example: + collapse_address_list([IPv4('1.1.0.0/24'), IPv4('1.1.1.0/24')]) -> + [IPv4('1.1.0.0/23')] + + Args: + addresses: A list of IPv4Network or IPv6Network objects. + + Returns: + A list of IPv4Network or IPv6Network objects depending on what we + were passed. + + Raises: + TypeError: If passed a list of mixed version objects. + + """ + i = 0 + addrs = [] + ips = [] + nets = [] + + # split IP addresses and networks + for ip in addresses: + if isinstance(ip, _BaseIP): + if ips and ips[-1]._version != ip._version: + raise TypeError("%s and %s are not of the same version" % ( + str(ip), str(ips[-1]))) + ips.append(ip) + elif ip._prefixlen == ip._max_prefixlen: + if ips and ips[-1]._version != ip._version: + raise TypeError("%s and %s are not of the same version" % ( + str(ip), str(ips[-1]))) + ips.append(ip.ip) + else: + if nets and nets[-1]._version != ip._version: + raise TypeError("%s and %s are not of the same version" % ( + str(ip), str(ips[-1]))) + nets.append(ip) + + # sort and dedup + ips = sorted(set(ips)) + nets = sorted(set(nets)) + + while i < len(ips): + (first, last) = _find_address_range(ips[i:]) + i = ips.index(last) + 1 + addrs.extend(summarize_address_range(first, last)) + + return _collapse_address_list_recursive(sorted( + addrs + nets, key=_BaseNet._get_networks_key)) + +# backwards compatibility +CollapseAddrList = collapse_address_list + +# Test whether this Python implementation supports byte objects that +# are not identical to str ones. +# We need to exclude platforms where bytes == str so that we can +# distinguish between packed representations and strings, for example +# b'12::' (the IPv4 address 49.50.58.58) and '12::' (an IPv6 address). +try: + _compat_has_real_bytes = bytes is not str +except NameError: # <Python2.6 + _compat_has_real_bytes = False + +def get_mixed_type_key(obj): + """Return a key suitable for sorting between networks and addresses. + + Address and Network objects are not sortable by default; they're + fundamentally different so the expression + + IPv4Address('1.1.1.1') <= IPv4Network('1.1.1.1/24') + + doesn't make any sense. There are some times however, where you may wish + to have ipaddr sort these for you anyway. If you need to do this, you + can use this function as the key= argument to sorted(). + + Args: + obj: either a Network or Address object. + Returns: + appropriate key. + + """ + if isinstance(obj, _BaseNet): + return obj._get_networks_key() + elif isinstance(obj, _BaseIP): + return obj._get_address_key() + return NotImplemented + +class _IPAddrBase(object): + + """The mother class.""" + + def __index__(self): + return self._ip + + def __int__(self): + return self._ip + + def __hex__(self): + return hex(self._ip) + + @property + def exploded(self): + """Return the longhand version of the IP address as a string.""" + return self._explode_shorthand_ip_string() + + @property + def compressed(self): + """Return the shorthand version of the IP address as a string.""" + return str(self) + + +class _BaseIP(_IPAddrBase): + + """A generic IP object. + + This IP class contains the version independent methods which are + used by single IP addresses. + + """ + + def __init__(self, address): + if '/' in str(address): + raise AddressValueError(address) + + def __eq__(self, other): + try: + return (self._ip == other._ip + and self._version == other._version + and isinstance(other, _BaseIP)) + except AttributeError: + return NotImplemented + + def __ne__(self, other): + eq = self.__eq__(other) + if eq is NotImplemented: + return NotImplemented + return not eq + + def __le__(self, other): + gt = self.__gt__(other) + if gt is NotImplemented: + return NotImplemented + return not gt + + def __ge__(self, other): + lt = self.__lt__(other) + if lt is NotImplemented: + return NotImplemented + return not lt + + def __lt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseIP): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self._ip != other._ip: + return self._ip < other._ip + return False + + def __gt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseIP): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self._ip != other._ip: + return self._ip > other._ip + return False + + # Shorthand for Integer addition and subtraction. This is not + # meant to ever support addition/subtraction of addresses. + def __add__(self, other): + if not isinstance(other, int): + return NotImplemented + return IPAddress(int(self) + other, version=self._version) + + def __sub__(self, other): + if not isinstance(other, int): + return NotImplemented + return IPAddress(int(self) - other, version=self._version) + + def __repr__(self): + return '%s(%r)' % (self.__class__.__name__, str(self)) + + def __str__(self): + return '%s' % self._string_from_ip_int(self._ip) + + def __hash__(self): + return hash(hex(long(self._ip))) + + def _get_address_key(self): + return (self._version, self) + + @property + def version(self): + raise NotImplementedError('BaseIP has no version') + + +class _BaseNet(_IPAddrBase): + + """A generic IP object. + + This IP class contains the version independent methods which are + used by networks. + + """ + + def __init__(self, address): + self._cache = {} + + def __repr__(self): + return '%s(%r)' % (self.__class__.__name__, str(self)) + + def iterhosts(self): + """Generate Iterator over usable hosts in a network. + + This is like __iter__ except it doesn't return the network + or broadcast addresses. + + """ + cur = int(self.network) + 1 + bcast = int(self.broadcast) - 1 + while cur <= bcast: + cur += 1 + yield IPAddress(cur - 1, version=self._version) + + def __iter__(self): + cur = int(self.network) + bcast = int(self.broadcast) + while cur <= bcast: + cur += 1 + yield IPAddress(cur - 1, version=self._version) + + def __getitem__(self, n): + network = int(self.network) + broadcast = int(self.broadcast) + if n >= 0: + if network + n > broadcast: + raise IndexError + return IPAddress(network + n, version=self._version) + else: + n += 1 + if broadcast + n < network: + raise IndexError + return IPAddress(broadcast + n, version=self._version) + + def __lt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseNet): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self.network != other.network: + return self.network < other.network + if self.netmask != other.netmask: + return self.netmask < other.netmask + return False + + def __gt__(self, other): + if self._version != other._version: + raise TypeError('%s and %s are not of the same version' % ( + str(self), str(other))) + if not isinstance(other, _BaseNet): + raise TypeError('%s and %s are not of the same type' % ( + str(self), str(other))) + if self.network != other.network: + return self.network > other.network + if self.netmask != other.netmask: + return self.netmask > other.netmask + return False + + def __le__(self, other): + gt = self.__gt__(other) + if gt is NotImplemented: + return NotImplemented + return not gt + + def __ge__(self, other): + lt = self.__lt__(other) + if lt is NotImplemented: + return NotImplemented + return not lt + + def __eq__(self, other): + try: + return (self._version == other._version + and self.network == other.network + and int(self.netmask) == int(other.netmask)) + except AttributeError: + return NotImplemented + + def __ne__(self, other): + eq = self.__eq__(other) + if eq is NotImplemented: + return NotImplemented + return not eq + + def __str__(self): + return '%s/%s' % (str(self.ip), + str(self._prefixlen)) + + def __hash__(self): + return hash(int(self.network) ^ int(self.netmask)) + + def __contains__(self, other): + # always false if one is v4 and the other is v6. + if self._version != other._version: + return False + # dealing with another network. + if isinstance(other, _BaseNet): + return (self.network <= other.network and + self.broadcast >= other.broadcast) + # dealing with another address + else: + return (int(self.network) <= int(other._ip) <= + int(self.broadcast)) + + def overlaps(self, other): + """Tell if self is partly contained in other.""" + return self.network in other or self.broadcast in other or ( + other.network in self or other.broadcast in self) + + @property + def network(self): + x = self._cache.get('network') + if x is None: + x = IPAddress(self._ip & int(self.netmask), version=self._version) + self._cache['network'] = x + return x + + @property + def broadcast(self): + x = self._cache.get('broadcast') + if x is None: + x = IPAddress(self._ip | int(self.hostmask), version=self._version) + self._cache['broadcast'] = x + return x + + @property + def hostmask(self): + x = self._cache.get('hostmask') + if x is None: + x = IPAddress(int(self.netmask) ^ self._ALL_ONES, + version=self._version) + self._cache['hostmask'] = x + return x + + @property + def with_prefixlen(self): + return '%s/%d' % (str(self.ip), self._prefixlen) + + @property + def with_netmask(self): + return '%s/%s' % (str(self.ip), str(self.netmask)) + + @property + def with_hostmask(self): + return '%s/%s' % (str(self.ip), str(self.hostmask)) + + @property + def numhosts(self): + """Number of hosts in the current subnet.""" + return int(self.broadcast) - int(self.network) + 1 + + @property + def version(self): + raise NotImplementedError('BaseNet has no version') + + @property + def prefixlen(self): + return self._prefixlen + + def address_exclude(self, other): + """Remove an address from a larger block. + + For example: + + addr1 = IP('10.1.1.0/24') + addr2 = IP('10.1.1.0/26') + addr1.address_exclude(addr2) = + [IP('10.1.1.64/26'), IP('10.1.1.128/25')] + + or IPv6: + + addr1 = IP('::1/32') + addr2 = IP('::1/128') + addr1.address_exclude(addr2) = [IP('::0/128'), + IP('::2/127'), + IP('::4/126'), + IP('::8/125'), + ... + IP('0:0:8000::/33')] + + Args: + other: An IP object of the same type. + + Returns: + A sorted list of IP objects addresses which is self minus + other. + + Raises: + TypeError: If self and other are of difffering address + versions, or if other is not a network object. + ValueError: If other is not completely contained by self. + + """ + if not self._version == other._version: + raise TypeError("%s and %s are not of the same version" % ( + str(self), str(other))) + + if not isinstance(other, _BaseNet): + raise TypeError("%s is not a network object" % str(other)) + + if other not in self: + raise ValueError('%s not contained in %s' % (str(other), + str(self))) + if other == self: + return [] + + ret_addrs = [] + + # Make sure we're comparing the network of other. + other = IPNetwork('%s/%s' % (str(other.network), str(other.prefixlen)), + version=other._version) + + s1, s2 = self.subnet() + while s1 != other and s2 != other: + if other in s1: + ret_addrs.append(s2) + s1, s2 = s1.subnet() + elif other in s2: + ret_addrs.append(s1) + s1, s2 = s2.subnet() + else: + # If we got here, there's a bug somewhere. + assert True == False, ('Error performing exclusion: ' + 's1: %s s2: %s other: %s' % + (str(s1), str(s2), str(other))) + if s1 == other: + ret_addrs.append(s2) + elif s2 == other: + ret_addrs.append(s1) + else: + # If we got here, there's a bug somewhere. + assert True == False, ('Error performing exclusion: ' + 's1: %s s2: %s other: %s' % + (str(s1), str(s2), str(other))) + + return sorted(ret_addrs, key=_BaseNet._get_networks_key) + + def compare_networks(self, other): + """Compare two IP objects. + + This is only concerned about the comparison of the integer + representation of the network addresses. This means that the + host bits aren't considered at all in this method. If you want + to compare host bits, you can easily enough do a + 'HostA._ip < HostB._ip' + + Args: + other: An IP object. + + Returns: + If the IP versions of self and other are the same, returns: + + -1 if self < other: + eg: IPv4('1.1.1.0/24') < IPv4('1.1.2.0/24') + IPv6('1080::200C:417A') < IPv6('1080::200B:417B') + 0 if self == other + eg: IPv4('1.1.1.1/24') == IPv4('1.1.1.2/24') + IPv6('1080::200C:417A/96') == IPv6('1080::200C:417B/96') + 1 if self > other + eg: IPv4('1.1.1.0/24') > IPv4('1.1.0.0/24') + IPv6('1080::1:200C:417A/112') > + IPv6('1080::0:200C:417A/112') + + If the IP versions of self and other are different, returns: + + -1 if self._version < other._version + eg: IPv4('10.0.0.1/24') < IPv6('::1/128') + 1 if self._version > other._version + eg: IPv6('::1/128') > IPv4('255.255.255.0/24') + + """ + if self._version < other._version: + return -1 + if self._version > other._version: + return 1 + # self._version == other._version below here: + if self.network < other.network: + return -1 + if self.network > other.network: + return 1 + # self.network == other.network below here: + if self.netmask < other.netmask: + return -1 + if self.netmask > other.netmask: + return 1 + # self.network == other.network and self.netmask == other.netmask + return 0 + + def _get_networks_key(self): + """Network-only key function. + + Returns an object that identifies this address' network and + netmask. This function is a suitable "key" argument for sorted() + and list.sort(). + + """ + return (self._version, self.network, self.netmask) + + def _ip_int_from_prefix(self, prefixlen=None): + """Turn the prefix length netmask into a int for comparison. + + Args: + prefixlen: An integer, the prefix length. + + Returns: + An integer. + + """ + if not prefixlen and prefixlen != 0: + prefixlen = self._prefixlen + return self._ALL_ONES ^ (self._ALL_ONES >> prefixlen) + + def _prefix_from_ip_int(self, ip_int, mask=32): + """Return prefix length from the decimal netmask. + + Args: + ip_int: An integer, the IP address. + mask: The netmask. Defaults to 32. + + Returns: + An integer, the prefix length. + + """ + while mask: + if ip_int & 1 == 1: + break + ip_int >>= 1 + mask -= 1 + + return mask + + def _ip_string_from_prefix(self, prefixlen=None): + """Turn a prefix length into a dotted decimal string. + + Args: + prefixlen: An integer, the netmask prefix length. + + Returns: + A string, the dotted decimal netmask string. + + """ + if not prefixlen: + prefixlen = self._prefixlen + return self._string_from_ip_int(self._ip_int_from_prefix(prefixlen)) + + def iter_subnets(self, prefixlen_diff=1, new_prefix=None): + """The subnets which join to make the current subnet. + + In the case that self contains only one IP + (self._prefixlen == 32 for IPv4 or self._prefixlen == 128 + for IPv6), return a list with just ourself. + + Args: + prefixlen_diff: An integer, the amount the prefix length + should be increased by. This should not be set if + new_prefix is also set. + new_prefix: The desired new prefix length. This must be a + larger number (smaller prefix) than the existing prefix. + This should not be set if prefixlen_diff is also set. + + Returns: + An iterator of IPv(4|6) objects. + + Raises: + ValueError: The prefixlen_diff is too small or too large. + OR + prefixlen_diff and new_prefix are both set or new_prefix + is a smaller number than the current prefix (smaller + number means a larger network) + + """ + if self._prefixlen == self._max_prefixlen: + yield self + return + + if new_prefix is not None: + if new_prefix < self._prefixlen: + raise ValueError('new prefix must be longer') + if prefixlen_diff != 1: + raise ValueError('cannot set prefixlen_diff and new_prefix') + prefixlen_diff = new_prefix - self._prefixlen + + if prefixlen_diff < 0: + raise ValueError('prefix length diff must be > 0') + new_prefixlen = self._prefixlen + prefixlen_diff + + if not self._is_valid_netmask(str(new_prefixlen)): + raise ValueError( + 'prefix length diff %d is invalid for netblock %s' % ( + new_prefixlen, str(self))) + + first = IPNetwork('%s/%s' % (str(self.network), + str(self._prefixlen + prefixlen_diff)), + version=self._version) + + yield first + current = first + while True: + broadcast = current.broadcast + if broadcast == self.broadcast: + return + new_addr = IPAddress(int(broadcast) + 1, version=self._version) + current = IPNetwork('%s/%s' % (str(new_addr), str(new_prefixlen)), + version=self._version) + + yield current + + def masked(self): + """Return the network object with the host bits masked out.""" + return IPNetwork('%s/%d' % (self.network, self._prefixlen), + version=self._version) + + def subnet(self, prefixlen_diff=1, new_prefix=None): + """Return a list of subnets, rather than an iterator.""" + return list(self.iter_subnets(prefixlen_diff, new_prefix)) + + def supernet(self, prefixlen_diff=1, new_prefix=None): + """The supernet containing the current network. + + Args: + prefixlen_diff: An integer, the amount the prefix length of + the network should be decreased by. For example, given a + /24 network and a prefixlen_diff of 3, a supernet with a + /21 netmask is returned. + + Returns: + An IPv4 network object. + + Raises: + ValueError: If self.prefixlen - prefixlen_diff < 0. I.e., you have a + negative prefix length. + OR + If prefixlen_diff and new_prefix are both set or new_prefix is a + larger number than the current prefix (larger number means a + smaller network) + + """ + if self._prefixlen == 0: + return self + + if new_prefix is not None: + if new_prefix > self._prefixlen: + raise ValueError('new prefix must be shorter') + if prefixlen_diff != 1: + raise ValueError('cannot set prefixlen_diff and new_prefix') + prefixlen_diff = self._prefixlen - new_prefix + + + if self.prefixlen - prefixlen_diff < 0: + raise ValueError( + 'current prefixlen is %d, cannot have a prefixlen_diff of %d' % + (self.prefixlen, prefixlen_diff)) + return IPNetwork('%s/%s' % (str(self.network), + str(self.prefixlen - prefixlen_diff)), + version=self._version) + + # backwards compatibility + Subnet = subnet + Supernet = supernet + AddressExclude = address_exclude + CompareNetworks = compare_networks + Contains = __contains__ + + +class _BaseV4(object): + + """Base IPv4 object. + + The following methods are used by IPv4 objects in both single IP + addresses and networks. + + """ + + # Equivalent to 255.255.255.255 or 32 bits of 1's. + _ALL_ONES = (2**IPV4LENGTH) - 1 + + def __init__(self, address): + self._version = 4 + self._max_prefixlen = IPV4LENGTH + + def _explode_shorthand_ip_string(self, ip_str=None): + if not ip_str: + ip_str = str(self) + return ip_str + + def _ip_int_from_string(self, ip_str): + """Turn the given IP string into an integer for comparison. + + Args: + ip_str: A string, the IP ip_str. + + Returns: + The IP ip_str as an integer. + + Raises: + AddressValueError: if the string isn't a valid IP string. + + """ + packed_ip = 0 + octets = ip_str.split('.') + if len(octets) != 4: + raise AddressValueError(ip_str) + for oc in octets: + try: + packed_ip = (packed_ip << 8) | int(oc) + except ValueError: + raise AddressValueError(ip_str) + return packed_ip + + def _string_from_ip_int(self, ip_int): + """Turns a 32-bit integer into dotted decimal notation. + + Args: + ip_int: An integer, the IP address. + + Returns: + The IP address as a string in dotted decimal notation. + + """ + octets = [] + for _ in xrange(4): + octets.insert(0, str(ip_int & 0xFF)) + ip_int >>= 8 + return '.'.join(octets) + + def _is_valid_ip(self, address): + """Validate the dotted decimal notation IP/netmask string. + + Args: + address: A string, either representing a quad-dotted ip + or an integer which is a valid IPv4 IP address. + + Returns: + A boolean, True if the string is a valid dotted decimal IP + string. + + """ + octets = address.split('.') + if len(octets) == 1: + # We have an integer rather than a dotted decimal IP. + try: + return int(address) >= 0 and int(address) <= self._ALL_ONES + except ValueError: + return False + + if len(octets) != 4: + return False + + for octet in octets: + try: + if not 0 <= int(octet) <= 255: + return False + except ValueError: + return False + return True + + @property + def max_prefixlen(self): + return self._max_prefixlen + + @property + def packed(self): + """The binary representation of this address.""" + return v4_int_to_packed(self._ip) + + @property + def version(self): + return self._version + + @property + def is_reserved(self): + """Test if the address is otherwise IETF reserved. + + Returns: + A boolean, True if the address is within the + reserved IPv4 Network range. + + """ + return self in IPv4Network('240.0.0.0/4') + + @property + def is_private(self): + """Test if this address is allocated for private networks. + + Returns: + A boolean, True if the address is reserved per RFC 1918. + + """ + return (self in IPv4Network('10.0.0.0/8') or + self in IPv4Network('172.16.0.0/12') or + self in IPv4Network('192.168.0.0/16')) + + @property + def is_multicast(self): + """Test if the address is reserved for multicast use. + + Returns: + A boolean, True if the address is multicast. + See RFC 3171 for details. + + """ + return self in IPv4Network('224.0.0.0/4') + + @property + def is_unspecified(self): + """Test if the address is unspecified. + + Returns: + A boolean, True if this is the unspecified address as defined in + RFC 5735 3. + + """ + return self in IPv4Network('0.0.0.0') + + @property + def is_loopback(self): + """Test if the address is a loopback address. + + Returns: + A boolean, True if the address is a loopback per RFC 3330. + + """ + return self in IPv4Network('127.0.0.0/8') + + @property + def is_link_local(self): + """Test if the address is reserved for link-local. + + Returns: + A boolean, True if the address is link-local per RFC 3927. + + """ + return self in IPv4Network('169.254.0.0/16') + + +class IPv4Address(_BaseV4, _BaseIP): + + """Represent and manipulate single IPv4 Addresses.""" + + def __init__(self, address): + + """ + Args: + address: A string or integer representing the IP + '192.168.1.1' + + Additionally, an integer can be passed, so + IPv4Address('192.168.1.1') == IPv4Address(3232235777). + or, more generally + IPv4Address(int(IPv4Address('192.168.1.1'))) == + IPv4Address('192.168.1.1') + + Raises: + AddressValueError: If ipaddr isn't a valid IPv4 address. + + """ + _BaseIP.__init__(self, address) + _BaseV4.__init__(self, address) + + # Efficient constructor from integer. + if isinstance(address, (int, long)): + self._ip = address + if address < 0 or address > self._ALL_ONES: + raise AddressValueError(address) + return + + # Constructing from a packed address + if _compat_has_real_bytes: + if isinstance(address, bytes) and len(address) == 4: + self._ip = struct.unpack('!I', address)[0] + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP string. + addr_str = str(address) + if not self._is_valid_ip(addr_str): + raise AddressValueError(addr_str) + + self._ip = self._ip_int_from_string(addr_str) + + +class IPv4Network(_BaseV4, _BaseNet): + + """This class represents and manipulates 32-bit IPv4 networks. + + Attributes: [examples for IPv4Network('1.2.3.4/27')] + ._ip: 16909060 + .ip: IPv4Address('1.2.3.4') + .network: IPv4Address('1.2.3.0') + .hostmask: IPv4Address('0.0.0.31') + .broadcast: IPv4Address('1.2.3.31') + .netmask: IPv4Address('255.255.255.224') + .prefixlen: 27 + + """ + + # the valid octets for host and netmasks. only useful for IPv4. + _valid_mask_octets = set((255, 254, 252, 248, 240, 224, 192, 128, 0)) + + def __init__(self, address, strict=False): + """Instantiate a new IPv4 network object. + + Args: + address: A string or integer representing the IP [& network]. + '192.168.1.1/24' + '192.168.1.1/255.255.255.0' + '192.168.1.1/0.0.0.255' + are all functionally the same in IPv4. Similarly, + '192.168.1.1' + '192.168.1.1/255.255.255.255' + '192.168.1.1/32' + are also functionaly equivalent. That is to say, failing to + provide a subnetmask will create an object with a mask of /32. + + If the mask (portion after the / in the argument) is given in + dotted quad form, it is treated as a netmask if it starts with a + non-zero field (e.g. /255.0.0.0 == /8) and as a hostmask if it + starts with a zero field (e.g. 0.255.255.255 == /8), with the + single exception of an all-zero mask which is treated as a + netmask == /0. If no mask is given, a default of /32 is used. + + Additionally, an integer can be passed, so + IPv4Network('192.168.1.1') == IPv4Network(3232235777). + or, more generally + IPv4Network(int(IPv4Network('192.168.1.1'))) == + IPv4Network('192.168.1.1') + + strict: A boolean. If true, ensure that we have been passed + A true network address, eg, 192.168.1.0/24 and not an + IP address on a network, eg, 192.168.1.1/24. + + Raises: + AddressValueError: If ipaddr isn't a valid IPv4 address. + NetmaskValueError: If the netmask isn't valid for + an IPv4 address. + ValueError: If strict was True and a network address was not + supplied. + + """ + _BaseNet.__init__(self, address) + _BaseV4.__init__(self, address) + + # Efficient constructor from integer. + if isinstance(address, (int, long)): + self._ip = address + self.ip = IPv4Address(self._ip) + self._prefixlen = self._max_prefixlen + self.netmask = IPv4Address(self._ALL_ONES) + if address < 0 or address > self._ALL_ONES: + raise AddressValueError(address) + return + + # Constructing from a packed address + if _compat_has_real_bytes: + if isinstance(address, bytes) and len(address) == 4: + self._ip = struct.unpack('!I', address)[0] + self.ip = IPv4Address(self._ip) + self._prefixlen = self._max_prefixlen + self.netmask = IPv4Address(self._ALL_ONES) + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP prefix string. + addr = str(address).split('/') + + if len(addr) > 2: + raise AddressValueError(address) + + if not self._is_valid_ip(addr[0]): + raise AddressValueError(addr[0]) + + self._ip = self._ip_int_from_string(addr[0]) + self.ip = IPv4Address(self._ip) + + if len(addr) == 2: + mask = addr[1].split('.') + if len(mask) == 4: + # We have dotted decimal netmask. + if self._is_valid_netmask(addr[1]): + self.netmask = IPv4Address(self._ip_int_from_string( + addr[1])) + elif self._is_hostmask(addr[1]): + self.netmask = IPv4Address( + self._ip_int_from_string(addr[1]) ^ self._ALL_ONES) + else: + raise NetmaskValueError('%s is not a valid netmask' + % addr[1]) + + self._prefixlen = self._prefix_from_ip_int(int(self.netmask)) + else: + # We have a netmask in prefix length form. + if not self._is_valid_netmask(addr[1]): + raise NetmaskValueError(addr[1]) + self._prefixlen = int(addr[1]) + self.netmask = IPv4Address(self._ip_int_from_prefix( + self._prefixlen)) + else: + self._prefixlen = self._max_prefixlen + self.netmask = IPv4Address(self._ip_int_from_prefix( + self._prefixlen)) + if strict: + if self.ip != self.network: + raise ValueError('%s has host bits set' % + self.ip) + + def _is_hostmask(self, ip_str): + """Test if the IP string is a hostmask (rather than a netmask). + + Args: + ip_str: A string, the potential hostmask. + + Returns: + A boolean, True if the IP string is a hostmask. + + """ + bits = ip_str.split('.') + try: + parts = [int(x) for x in bits if int(x) in self._valid_mask_octets] + except ValueError: + return False + if len(parts) != len(bits): + return False + if parts[0] < parts[-1]: + return True + return False + + def _is_valid_netmask(self, netmask): + """Verify that the netmask is valid. + + Args: + netmask: A string, either a prefix or dotted decimal + netmask. + + Returns: + A boolean, True if the prefix represents a valid IPv4 + netmask. + + """ + mask = netmask.split('.') + if len(mask) == 4: + if [x for x in mask if int(x) not in self._valid_mask_octets]: + return False + if [y for idx, y in enumerate(mask) if idx > 0 and + y > mask[idx - 1]]: + return False + return True + try: + netmask = int(netmask) + except ValueError: + return False + return 0 <= netmask <= self._max_prefixlen + + # backwards compatibility + IsRFC1918 = lambda self: self.is_private + IsMulticast = lambda self: self.is_multicast + IsLoopback = lambda self: self.is_loopback + IsLinkLocal = lambda self: self.is_link_local + + +class _BaseV6(object): + + """Base IPv6 object. + + The following methods are used by IPv6 objects in both single IP + addresses and networks. + + """ + + _ALL_ONES = (2**IPV6LENGTH) - 1 + + def __init__(self, address): + self._version = 6 + self._max_prefixlen = IPV6LENGTH + + def _ip_int_from_string(self, ip_str=None): + """Turn an IPv6 ip_str into an integer. + + Args: + ip_str: A string, the IPv6 ip_str. + + Returns: + A long, the IPv6 ip_str. + + Raises: + AddressValueError: if ip_str isn't a valid IP Address. + + """ + if not ip_str: + ip_str = str(self.ip) + + ip_int = 0 + + # Do we have an IPv4 mapped (::ffff:a.b.c.d) or compact (::a.b.c.d) + # ip_str? + fields = ip_str.split(':') + if fields[-1].count('.') == 3: + ipv4_string = fields.pop() + ipv4_int = IPv4Network(ipv4_string)._ip + octets = [] + for _ in xrange(2): + octets.append(hex(ipv4_int & 0xFFFF).lstrip('0x').rstrip('L')) + ipv4_int >>= 16 + fields.extend(reversed(octets)) + ip_str = ':'.join(fields) + + fields = self._explode_shorthand_ip_string(ip_str).split(':') + for field in fields: + try: + ip_int = (ip_int << 16) + int(field or '0', 16) + except ValueError: + raise AddressValueError(ip_str) + + return ip_int + + def _compress_hextets(self, hextets): + """Compresses a list of hextets. + + Compresses a list of strings, replacing the longest continuous + sequence of "0" in the list with "" and adding empty strings at + the beginning or at the end of the string such that subsequently + calling ":".join(hextets) will produce the compressed version of + the IPv6 address. + + Args: + hextets: A list of strings, the hextets to compress. + + Returns: + A list of strings. + + """ + best_doublecolon_start = -1 + best_doublecolon_len = 0 + doublecolon_start = -1 + doublecolon_len = 0 + for index in range(len(hextets)): + if hextets[index] == '0': + doublecolon_len += 1 + if doublecolon_start == -1: + # Start of a sequence of zeros. + doublecolon_start = index + if doublecolon_len > best_doublecolon_len: + # This is the longest sequence of zeros so far. + best_doublecolon_len = doublecolon_len + best_doublecolon_start = doublecolon_start + else: + doublecolon_len = 0 + doublecolon_start = -1 + + if best_doublecolon_len > 1: + best_doublecolon_end = (best_doublecolon_start + + best_doublecolon_len) + # For zeros at the end of the address. + if best_doublecolon_end == len(hextets): + hextets += [''] + hextets[best_doublecolon_start:best_doublecolon_end] = [''] + # For zeros at the beginning of the address. + if best_doublecolon_start == 0: + hextets = [''] + hextets + + return hextets + + def _string_from_ip_int(self, ip_int=None): + """Turns a 128-bit integer into hexadecimal notation. + + Args: + ip_int: An integer, the IP address. + + Returns: + A string, the hexadecimal representation of the address. + + Raises: + ValueError: The address is bigger than 128 bits of all ones. + + """ + if not ip_int and ip_int != 0: + ip_int = int(self._ip) + + if ip_int > self._ALL_ONES: + raise ValueError('IPv6 address is too large') + + hex_str = '%032x' % ip_int + hextets = [] + for x in range(0, 32, 4): + hextets.append('%x' % int(hex_str[x:x+4], 16)) + + hextets = self._compress_hextets(hextets) + return ':'.join(hextets) + + def _explode_shorthand_ip_string(self, ip_str=None): + """Expand a shortened IPv6 address. + + Args: + ip_str: A string, the IPv6 address. + + Returns: + A string, the expanded IPv6 address. + + """ + if not ip_str: + ip_str = str(self) + if isinstance(self, _BaseNet): + ip_str = str(self.ip) + + if self._is_shorthand_ip(ip_str): + new_ip = [] + hextet = ip_str.split('::') + sep = len(hextet[0].split(':')) + len(hextet[1].split(':')) + new_ip = hextet[0].split(':') + + for _ in xrange(8 - sep): + new_ip.append('0000') + new_ip += hextet[1].split(':') + + # Now need to make sure every hextet is 4 lower case characters. + # If a hextet is < 4 characters, we've got missing leading 0's. + ret_ip = [] + for hextet in new_ip: + ret_ip.append(('0' * (4 - len(hextet)) + hextet).lower()) + return ':'.join(ret_ip) + # We've already got a longhand ip_str. + return ip_str + + def _is_valid_ip(self, ip_str): + """Ensure we have a valid IPv6 address. + + Probably not as exhaustive as it should be. + + Args: + ip_str: A string, the IPv6 address. + + Returns: + A boolean, True if this is a valid IPv6 address. + + """ + # We need to have at least one ':'. + if ':' not in ip_str: + return False + + # We can only have one '::' shortener. + if ip_str.count('::') > 1: + return False + + # '::' should be encompassed by start, digits or end. + if ':::' in ip_str: + return False + + # A single colon can neither start nor end an address. + if ((ip_str.startswith(':') and not ip_str.startswith('::')) or + (ip_str.endswith(':') and not ip_str.endswith('::'))): + return False + + # If we have no concatenation, we need to have 8 fields with 7 ':'. + if '::' not in ip_str and ip_str.count(':') != 7: + # We might have an IPv4 mapped address. + if ip_str.count('.') != 3: + return False + + ip_str = self._explode_shorthand_ip_string(ip_str) + + # Now that we have that all squared away, let's check that each of the + # hextets are between 0x0 and 0xFFFF. + for hextet in ip_str.split(':'): + if hextet.count('.') == 3: + # If we have an IPv4 mapped address, the IPv4 portion has to + # be at the end of the IPv6 portion. + if not ip_str.split(':')[-1] == hextet: + return False + try: + IPv4Network(hextet) + except AddressValueError: + return False + else: + try: + # a value error here means that we got a bad hextet, + # something like 0xzzzz + if int(hextet, 16) < 0x0 or int(hextet, 16) > 0xFFFF: + return False + except ValueError: + return False + return True + + def _is_shorthand_ip(self, ip_str=None): + """Determine if the address is shortened. + + Args: + ip_str: A string, the IPv6 address. + + Returns: + A boolean, True if the address is shortened. + + """ + if ip_str.count('::') == 1: + return True + return False + + @property + def max_prefixlen(self): + return self._max_prefixlen + + @property + def packed(self): + """The binary representation of this address.""" + return v6_int_to_packed(self._ip) + + @property + def version(self): + return self._version + + @property + def is_multicast(self): + """Test if the address is reserved for multicast use. + + Returns: + A boolean, True if the address is a multicast address. + See RFC 2373 2.7 for details. + + """ + return self in IPv6Network('ff00::/8') + + @property + def is_reserved(self): + """Test if the address is otherwise IETF reserved. + + Returns: + A boolean, True if the address is within one of the + reserved IPv6 Network ranges. + + """ + return (self in IPv6Network('::/8') or + self in IPv6Network('100::/8') or + self in IPv6Network('200::/7') or + self in IPv6Network('400::/6') or + self in IPv6Network('800::/5') or + self in IPv6Network('1000::/4') or + self in IPv6Network('4000::/3') or + self in IPv6Network('6000::/3') or + self in IPv6Network('8000::/3') or + self in IPv6Network('A000::/3') or + self in IPv6Network('C000::/3') or + self in IPv6Network('E000::/4') or + self in IPv6Network('F000::/5') or + self in IPv6Network('F800::/6') or + self in IPv6Network('FE00::/9')) + + @property + def is_unspecified(self): + """Test if the address is unspecified. + + Returns: + A boolean, True if this is the unspecified address as defined in + RFC 2373 2.5.2. + + """ + return (self == IPv6Network('::') or self == IPv6Address('::')) + + @property + def is_loopback(self): + """Test if the address is a loopback address. + + Returns: + A boolean, True if the address is a loopback address as defined in + RFC 2373 2.5.3. + + """ + return (self == IPv6Network('::1') or self == IPv6Address('::1')) + + @property + def is_link_local(self): + """Test if the address is reserved for link-local. + + Returns: + A boolean, True if the address is reserved per RFC 4291. + + """ + return self in IPv6Network('fe80::/10') + + @property + def is_site_local(self): + """Test if the address is reserved for site-local. + + Note that the site-local address space has been deprecated by RFC 3879. + Use is_private to test if this address is in the space of unique local + addresses as defined by RFC 4193. + + Returns: + A boolean, True if the address is reserved per RFC 3513 2.5.6. + + """ + return self in IPv6Network('fec0::/10') + + @property + def is_private(self): + """Test if this address is allocated for private networks. + + Returns: + A boolean, True if the address is reserved per RFC 4193. + + """ + return self in IPv6Network('fc00::/7') + + @property + def ipv4_mapped(self): + """Return the IPv4 mapped address. + + Returns: + If the IPv6 address is a v4 mapped address, return the + IPv4 mapped address. Return None otherwise. + + """ + hextets = self._explode_shorthand_ip_string().split(':') + if hextets[-3] != 'ffff': + return None + try: + return IPv4Address(int('%s%s' % (hextets[-2], hextets[-1]), 16)) + except AddressValueError: + return None + + @property + def teredo(self): + """Tuple of embedded teredo IPs. + + Returns: + Tuple of the (server, client) IPs or None if the address + doesn't appear to be a teredo address (doesn't start with + 2001) + + """ + bits = self._explode_shorthand_ip_string().split(':') + if not bits[0] == '2001': + return None + return (IPv4Address(int(''.join(bits[2:4]), 16)), + IPv4Address(int(''.join(bits[6:]), 16) ^ 0xFFFFFFFF)) + + @property + def sixtofour(self): + """Return the IPv4 6to4 embedded address. + + Returns: + The IPv4 6to4-embedded address if present or None if the + address doesn't appear to contain a 6to4 embedded address. + + """ + bits = self._explode_shorthand_ip_string().split(':') + if not bits[0] == '2002': + return None + return IPv4Address(int(''.join(bits[1:3]), 16)) + + +class IPv6Address(_BaseV6, _BaseIP): + + """Represent and manipulate single IPv6 Addresses. + """ + + def __init__(self, address): + """Instantiate a new IPv6 address object. + + Args: + address: A string or integer representing the IP + + Additionally, an integer can be passed, so + IPv6Address('2001:4860::') == + IPv6Address(42541956101370907050197289607612071936L). + or, more generally + IPv6Address(IPv6Address('2001:4860::')._ip) == + IPv6Address('2001:4860::') + + Raises: + AddressValueError: If address isn't a valid IPv6 address. + + """ + _BaseIP.__init__(self, address) + _BaseV6.__init__(self, address) + + # Efficient constructor from integer. + if isinstance(address, (int, long)): + self._ip = address + if address < 0 or address > self._ALL_ONES: + raise AddressValueError(address) + return + + # Constructing from a packed address + if _compat_has_real_bytes: + if isinstance(address, bytes) and len(address) == 16: + tmp = struct.unpack('!QQ', address) + self._ip = (tmp[0] << 64) | tmp[1] + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP string. + addr_str = str(address) + if not addr_str: + raise AddressValueError('') + + if not self._is_valid_ip(addr_str): + raise AddressValueError(addr_str) + + self._ip = self._ip_int_from_string(addr_str) + + +class IPv6Network(_BaseV6, _BaseNet): + + """This class represents and manipulates 128-bit IPv6 networks. + + Attributes: [examples for IPv6('2001:658:22A:CAFE:200::1/64')] + .ip: IPv6Address('2001:658:22a:cafe:200::1') + .network: IPv6Address('2001:658:22a:cafe::') + .hostmask: IPv6Address('::ffff:ffff:ffff:ffff') + .broadcast: IPv6Address('2001:658:22a:cafe:ffff:ffff:ffff:ffff') + .netmask: IPv6Address('ffff:ffff:ffff:ffff::') + .prefixlen: 64 + + """ + + + def __init__(self, address, strict=False): + """Instantiate a new IPv6 Network object. + + Args: + address: A string or integer representing the IPv6 network or the IP + and prefix/netmask. + '2001:4860::/128' + '2001:4860:0000:0000:0000:0000:0000:0000/128' + '2001:4860::' + are all functionally the same in IPv6. That is to say, + failing to provide a subnetmask will create an object with + a mask of /128. + + Additionally, an integer can be passed, so + IPv6Network('2001:4860::') == + IPv6Network(42541956101370907050197289607612071936L). + or, more generally + IPv6Network(IPv6Network('2001:4860::')._ip) == + IPv6Network('2001:4860::') + + strict: A boolean. If true, ensure that we have been passed + A true network address, eg, 192.168.1.0/24 and not an + IP address on a network, eg, 192.168.1.1/24. + + Raises: + AddressValueError: If address isn't a valid IPv6 address. + NetmaskValueError: If the netmask isn't valid for + an IPv6 address. + ValueError: If strict was True and a network address was not + supplied. + + """ + _BaseNet.__init__(self, address) + _BaseV6.__init__(self, address) + + # Efficient constructor from integer. + if isinstance(address, (int, long)): + self._ip = address + self.ip = IPv6Address(self._ip) + self._prefixlen = self._max_prefixlen + self.netmask = IPv6Address(self._ALL_ONES) + if address < 0 or address > self._ALL_ONES: + raise AddressValueError(address) + return + + # Constructing from a packed address + if _compat_has_real_bytes: + if isinstance(address, bytes) and len(address) == 16: + tmp = struct.unpack('!QQ', address) + self._ip = (tmp[0] << 64) | tmp[1] + self.ip = IPv6Address(self._ip) + self._prefixlen = self._max_prefixlen + self.netmask = IPv6Address(self._ALL_ONES) + return + + # Assume input argument to be string or any object representation + # which converts into a formatted IP prefix string. + addr = str(address).split('/') + + if len(addr) > 2: + raise AddressValueError(address) + + if not self._is_valid_ip(addr[0]): + raise AddressValueError(addr[0]) + + if len(addr) == 2: + if self._is_valid_netmask(addr[1]): + self._prefixlen = int(addr[1]) + else: + raise NetmaskValueError(addr[1]) + else: + self._prefixlen = self._max_prefixlen + + self.netmask = IPv6Address(self._ip_int_from_prefix(self._prefixlen)) + + self._ip = self._ip_int_from_string(addr[0]) + self.ip = IPv6Address(self._ip) + + if strict: + if self.ip != self.network: + raise ValueError('%s has host bits set' % + self.ip) + + def _is_valid_netmask(self, prefixlen): + """Verify that the netmask/prefixlen is valid. + + Args: + prefixlen: A string, the netmask in prefix length format. + + Returns: + A boolean, True if the prefix represents a valid IPv6 + netmask. + + """ + try: + prefixlen = int(prefixlen) + except ValueError: + return False + return 0 <= prefixlen <= self._max_prefixlen + + @property + def with_netmask(self): + return self.with_prefixlen diff --git a/third_party/ply/__init__.py b/third_party/ply/__init__.py new file mode 100644 index 0000000..853a985 --- /dev/null +++ b/third_party/ply/__init__.py @@ -0,0 +1,4 @@ +# PLY package +# Author: David Beazley (dave@dabeaz.com) + +__all__ = ['lex','yacc'] diff --git a/third_party/ply/lex.py b/third_party/ply/lex.py new file mode 100644 index 0000000..267ec10 --- /dev/null +++ b/third_party/ply/lex.py @@ -0,0 +1,1058 @@ +# ----------------------------------------------------------------------------- +# ply: lex.py +# +# Copyright (C) 2001-2009, +# David M. Beazley (Dabeaz LLC) +# 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 the David Beazley or Dabeaz LLC 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. +# ----------------------------------------------------------------------------- + +__version__ = "3.3" +__tabversion__ = "3.2" # Version of table file used + +import re, sys, types, copy, os + +# This tuple contains known string types +try: + # Python 2.6 + StringTypes = (types.StringType, types.UnicodeType) +except AttributeError: + # Python 3.0 + StringTypes = (str, bytes) + +# Extract the code attribute of a function. Different implementations +# are for Python 2/3 compatibility. + +if sys.version_info[0] < 3: + def func_code(f): + return f.func_code +else: + def func_code(f): + return f.__code__ + +# This regular expression is used to match valid token names +_is_identifier = re.compile(r'^[a-zA-Z0-9_]+$') + +# Exception thrown when invalid token encountered and no default error +# handler is defined. + +class LexError(Exception): + def __init__(self,message,s): + self.args = (message,) + self.text = s + +# Token class. This class is used to represent the tokens produced. +class LexToken(object): + def __str__(self): + return "LexToken(%s,%r,%d,%d)" % (self.type,self.value,self.lineno,self.lexpos) + def __repr__(self): + return str(self) + +# This object is a stand-in for a logging object created by the +# logging module. + +class PlyLogger(object): + def __init__(self,f): + self.f = f + def critical(self,msg,*args,**kwargs): + self.f.write((msg % args) + "\n") + + def warning(self,msg,*args,**kwargs): + self.f.write("WARNING: "+ (msg % args) + "\n") + + def error(self,msg,*args,**kwargs): + self.f.write("ERROR: " + (msg % args) + "\n") + + info = critical + debug = critical + +# Null logger is used when no output is generated. Does nothing. +class NullLogger(object): + def __getattribute__(self,name): + return self + def __call__(self,*args,**kwargs): + return self + +# ----------------------------------------------------------------------------- +# === Lexing Engine === +# +# The following Lexer class implements the lexer runtime. There are only +# a few public methods and attributes: +# +# input() - Store a new string in the lexer +# token() - Get the next token +# clone() - Clone the lexer +# +# lineno - Current line number +# lexpos - Current position in the input string +# ----------------------------------------------------------------------------- + +class Lexer: + def __init__(self): + self.lexre = None # Master regular expression. This is a list of + # tuples (re,findex) where re is a compiled + # regular expression and findex is a list + # mapping regex group numbers to rules + self.lexretext = None # Current regular expression strings + self.lexstatere = {} # Dictionary mapping lexer states to master regexs + self.lexstateretext = {} # Dictionary mapping lexer states to regex strings + self.lexstaterenames = {} # Dictionary mapping lexer states to symbol names + self.lexstate = "INITIAL" # Current lexer state + self.lexstatestack = [] # Stack of lexer states + self.lexstateinfo = None # State information + self.lexstateignore = {} # Dictionary of ignored characters for each state + self.lexstateerrorf = {} # Dictionary of error functions for each state + self.lexreflags = 0 # Optional re compile flags + self.lexdata = None # Actual input data (as a string) + self.lexpos = 0 # Current position in input text + self.lexlen = 0 # Length of the input text + self.lexerrorf = None # Error rule (if any) + self.lextokens = None # List of valid tokens + self.lexignore = "" # Ignored characters + self.lexliterals = "" # Literal characters that can be passed through + self.lexmodule = None # Module + self.lineno = 1 # Current line number + self.lexoptimize = 0 # Optimized mode + + def clone(self,object=None): + c = copy.copy(self) + + # If the object parameter has been supplied, it means we are attaching the + # lexer to a new object. In this case, we have to rebind all methods in + # the lexstatere and lexstateerrorf tables. + + if object: + newtab = { } + for key, ritem in self.lexstatere.items(): + newre = [] + for cre, findex in ritem: + newfindex = [] + for f in findex: + if not f or not f[0]: + newfindex.append(f) + continue + newfindex.append((getattr(object,f[0].__name__),f[1])) + newre.append((cre,newfindex)) + newtab[key] = newre + c.lexstatere = newtab + c.lexstateerrorf = { } + for key, ef in self.lexstateerrorf.items(): + c.lexstateerrorf[key] = getattr(object,ef.__name__) + c.lexmodule = object + return c + + # ------------------------------------------------------------ + # writetab() - Write lexer information to a table file + # ------------------------------------------------------------ + def writetab(self,tabfile,outputdir=""): + if isinstance(tabfile,types.ModuleType): + return + basetabfilename = tabfile.split(".")[-1] + filename = os.path.join(outputdir,basetabfilename)+".py" + tf = open(filename,"w") + tf.write("# %s.py. This file automatically created by PLY (version %s). Don't edit!\n" % (tabfile,__version__)) + tf.write("_tabversion = %s\n" % repr(__version__)) + tf.write("_lextokens = %s\n" % repr(self.lextokens)) + tf.write("_lexreflags = %s\n" % repr(self.lexreflags)) + tf.write("_lexliterals = %s\n" % repr(self.lexliterals)) + tf.write("_lexstateinfo = %s\n" % repr(self.lexstateinfo)) + + tabre = { } + # Collect all functions in the initial state + initial = self.lexstatere["INITIAL"] + initialfuncs = [] + for part in initial: + for f in part[1]: + if f and f[0]: + initialfuncs.append(f) + + for key, lre in self.lexstatere.items(): + titem = [] + for i in range(len(lre)): + titem.append((self.lexstateretext[key][i],_funcs_to_names(lre[i][1],self.lexstaterenames[key][i]))) + tabre[key] = titem + + tf.write("_lexstatere = %s\n" % repr(tabre)) + tf.write("_lexstateignore = %s\n" % repr(self.lexstateignore)) + + taberr = { } + for key, ef in self.lexstateerrorf.items(): + if ef: + taberr[key] = ef.__name__ + else: + taberr[key] = None + tf.write("_lexstateerrorf = %s\n" % repr(taberr)) + tf.close() + + # ------------------------------------------------------------ + # readtab() - Read lexer information from a tab file + # ------------------------------------------------------------ + def readtab(self,tabfile,fdict): + if isinstance(tabfile,types.ModuleType): + lextab = tabfile + else: + if sys.version_info[0] < 3: + exec("import %s as lextab" % tabfile) + else: + env = { } + exec("import %s as lextab" % tabfile, env,env) + lextab = env['lextab'] + + if getattr(lextab,"_tabversion","0.0") != __version__: + raise ImportError("Inconsistent PLY version") + + self.lextokens = lextab._lextokens + self.lexreflags = lextab._lexreflags + self.lexliterals = lextab._lexliterals + self.lexstateinfo = lextab._lexstateinfo + self.lexstateignore = lextab._lexstateignore + self.lexstatere = { } + self.lexstateretext = { } + for key,lre in lextab._lexstatere.items(): + titem = [] + txtitem = [] + for i in range(len(lre)): + titem.append((re.compile(lre[i][0],lextab._lexreflags | re.VERBOSE),_names_to_funcs(lre[i][1],fdict))) + txtitem.append(lre[i][0]) + self.lexstatere[key] = titem + self.lexstateretext[key] = txtitem + self.lexstateerrorf = { } + for key,ef in lextab._lexstateerrorf.items(): + self.lexstateerrorf[key] = fdict[ef] + self.begin('INITIAL') + + # ------------------------------------------------------------ + # input() - Push a new string into the lexer + # ------------------------------------------------------------ + def input(self,s): + # Pull off the first character to see if s looks like a string + c = s[:1] + if not isinstance(c,StringTypes): + raise ValueError("Expected a string") + self.lexdata = s + self.lexpos = 0 + self.lexlen = len(s) + + # ------------------------------------------------------------ + # begin() - Changes the lexing state + # ------------------------------------------------------------ + def begin(self,state): + if not state in self.lexstatere: + raise ValueError("Undefined state") + self.lexre = self.lexstatere[state] + self.lexretext = self.lexstateretext[state] + self.lexignore = self.lexstateignore.get(state,"") + self.lexerrorf = self.lexstateerrorf.get(state,None) + self.lexstate = state + + # ------------------------------------------------------------ + # push_state() - Changes the lexing state and saves old on stack + # ------------------------------------------------------------ + def push_state(self,state): + self.lexstatestack.append(self.lexstate) + self.begin(state) + + # ------------------------------------------------------------ + # pop_state() - Restores the previous state + # ------------------------------------------------------------ + def pop_state(self): + self.begin(self.lexstatestack.pop()) + + # ------------------------------------------------------------ + # current_state() - Returns the current lexing state + # ------------------------------------------------------------ + def current_state(self): + return self.lexstate + + # ------------------------------------------------------------ + # skip() - Skip ahead n characters + # ------------------------------------------------------------ + def skip(self,n): + self.lexpos += n + + # ------------------------------------------------------------ + # opttoken() - Return the next token from the Lexer + # + # Note: This function has been carefully implemented to be as fast + # as possible. Don't make changes unless you really know what + # you are doing + # ------------------------------------------------------------ + def token(self): + # Make local copies of frequently referenced attributes + lexpos = self.lexpos + lexlen = self.lexlen + lexignore = self.lexignore + lexdata = self.lexdata + + while lexpos < lexlen: + # This code provides some short-circuit code for whitespace, tabs, and other ignored characters + if lexdata[lexpos] in lexignore: + lexpos += 1 + continue + + # Look for a regular expression match + for lexre,lexindexfunc in self.lexre: + m = lexre.match(lexdata,lexpos) + if not m: continue + + # Create a token for return + tok = LexToken() + tok.value = m.group() + tok.lineno = self.lineno + tok.lexpos = lexpos + + i = m.lastindex + func,tok.type = lexindexfunc[i] + + if not func: + # If no token type was set, it's an ignored token + if tok.type: + self.lexpos = m.end() + return tok + else: + lexpos = m.end() + break + + lexpos = m.end() + + # If token is processed by a function, call it + + tok.lexer = self # Set additional attributes useful in token rules + self.lexmatch = m + self.lexpos = lexpos + + newtok = func(tok) + + # Every function must return a token, if nothing, we just move to next token + if not newtok: + lexpos = self.lexpos # This is here in case user has updated lexpos. + lexignore = self.lexignore # This is here in case there was a state change + break + + # Verify type of the token. If not in the token map, raise an error + if not self.lexoptimize: + if not newtok.type in self.lextokens: + raise LexError("%s:%d: Rule '%s' returned an unknown token type '%s'" % ( + func_code(func).co_filename, func_code(func).co_firstlineno, + func.__name__, newtok.type),lexdata[lexpos:]) + + return newtok + else: + # No match, see if in literals + if lexdata[lexpos] in self.lexliterals: + tok = LexToken() + tok.value = lexdata[lexpos] + tok.lineno = self.lineno + tok.type = tok.value + tok.lexpos = lexpos + self.lexpos = lexpos + 1 + return tok + + # No match. Call t_error() if defined. + if self.lexerrorf: + tok = LexToken() + tok.value = self.lexdata[lexpos:] + tok.lineno = self.lineno + tok.type = "error" + tok.lexer = self + tok.lexpos = lexpos + self.lexpos = lexpos + newtok = self.lexerrorf(tok) + if lexpos == self.lexpos: + # Error method didn't change text position at all. This is an error. + raise LexError("Scanning error. Illegal character '%s'" % (lexdata[lexpos]), lexdata[lexpos:]) + lexpos = self.lexpos + if not newtok: continue + return newtok + + self.lexpos = lexpos + raise LexError("Illegal character '%s' at index %d" % (lexdata[lexpos],lexpos), lexdata[lexpos:]) + + self.lexpos = lexpos + 1 + if self.lexdata is None: + raise RuntimeError("No input string given with input()") + return None + + # Iterator interface + def __iter__(self): + return self + + def next(self): + t = self.token() + if t is None: + raise StopIteration + return t + + __next__ = next + +# ----------------------------------------------------------------------------- +# ==== Lex Builder === +# +# The functions and classes below are used to collect lexing information +# and build a Lexer object from it. +# ----------------------------------------------------------------------------- + +# ----------------------------------------------------------------------------- +# get_caller_module_dict() +# +# This function returns a dictionary containing all of the symbols defined within +# a caller further down the call stack. This is used to get the environment +# associated with the yacc() call if none was provided. +# ----------------------------------------------------------------------------- + +def get_caller_module_dict(levels): + try: + raise RuntimeError + except RuntimeError: + e,b,t = sys.exc_info() + f = t.tb_frame + while levels > 0: + f = f.f_back + levels -= 1 + ldict = f.f_globals.copy() + if f.f_globals != f.f_locals: + ldict.update(f.f_locals) + + return ldict + +# ----------------------------------------------------------------------------- +# _funcs_to_names() +# +# Given a list of regular expression functions, this converts it to a list +# suitable for output to a table file +# ----------------------------------------------------------------------------- + +def _funcs_to_names(funclist,namelist): + result = [] + for f,name in zip(funclist,namelist): + if f and f[0]: + result.append((name, f[1])) + else: + result.append(f) + return result + +# ----------------------------------------------------------------------------- +# _names_to_funcs() +# +# Given a list of regular expression function names, this converts it back to +# functions. +# ----------------------------------------------------------------------------- + +def _names_to_funcs(namelist,fdict): + result = [] + for n in namelist: + if n and n[0]: + result.append((fdict[n[0]],n[1])) + else: + result.append(n) + return result + +# ----------------------------------------------------------------------------- +# _form_master_re() +# +# This function takes a list of all of the regex components and attempts to +# form the master regular expression. Given limitations in the Python re +# module, it may be necessary to break the master regex into separate expressions. +# ----------------------------------------------------------------------------- + +def _form_master_re(relist,reflags,ldict,toknames): + if not relist: return [] + regex = "|".join(relist) + try: + lexre = re.compile(regex,re.VERBOSE | reflags) + + # Build the index to function map for the matching engine + lexindexfunc = [ None ] * (max(lexre.groupindex.values())+1) + lexindexnames = lexindexfunc[:] + + for f,i in lexre.groupindex.items(): + handle = ldict.get(f,None) + if type(handle) in (types.FunctionType, types.MethodType): + lexindexfunc[i] = (handle,toknames[f]) + lexindexnames[i] = f + elif handle is not None: + lexindexnames[i] = f + if f.find("ignore_") > 0: + lexindexfunc[i] = (None,None) + else: + lexindexfunc[i] = (None, toknames[f]) + + return [(lexre,lexindexfunc)],[regex],[lexindexnames] + except Exception: + m = int(len(relist)/2) + if m == 0: m = 1 + llist, lre, lnames = _form_master_re(relist[:m],reflags,ldict,toknames) + rlist, rre, rnames = _form_master_re(relist[m:],reflags,ldict,toknames) + return llist+rlist, lre+rre, lnames+rnames + +# ----------------------------------------------------------------------------- +# def _statetoken(s,names) +# +# Given a declaration name s of the form "t_" and a dictionary whose keys are +# state names, this function returns a tuple (states,tokenname) where states +# is a tuple of state names and tokenname is the name of the token. For example, +# calling this with s = "t_foo_bar_SPAM" might return (('foo','bar'),'SPAM') +# ----------------------------------------------------------------------------- + +def _statetoken(s,names): + nonstate = 1 + parts = s.split("_") + for i in range(1,len(parts)): + if not parts[i] in names and parts[i] != 'ANY': break + if i > 1: + states = tuple(parts[1:i]) + else: + states = ('INITIAL',) + + if 'ANY' in states: + states = tuple(names) + + tokenname = "_".join(parts[i:]) + return (states,tokenname) + + +# ----------------------------------------------------------------------------- +# LexerReflect() +# +# This class represents information needed to build a lexer as extracted from a +# user's input file. +# ----------------------------------------------------------------------------- +class LexerReflect(object): + def __init__(self,ldict,log=None,reflags=0): + self.ldict = ldict + self.error_func = None + self.tokens = [] + self.reflags = reflags + self.stateinfo = { 'INITIAL' : 'inclusive'} + self.files = {} + self.error = 0 + + if log is None: + self.log = PlyLogger(sys.stderr) + else: + self.log = log + + # Get all of the basic information + def get_all(self): + self.get_tokens() + self.get_literals() + self.get_states() + self.get_rules() + + # Validate all of the information + def validate_all(self): + self.validate_tokens() + self.validate_literals() + self.validate_rules() + return self.error + + # Get the tokens map + def get_tokens(self): + tokens = self.ldict.get("tokens",None) + if not tokens: + self.log.error("No token list is defined") + self.error = 1 + return + + if not isinstance(tokens,(list, tuple)): + self.log.error("tokens must be a list or tuple") + self.error = 1 + return + + if not tokens: + self.log.error("tokens is empty") + self.error = 1 + return + + self.tokens = tokens + + # Validate the tokens + def validate_tokens(self): + terminals = {} + for n in self.tokens: + if not _is_identifier.match(n): + self.log.error("Bad token name '%s'",n) + self.error = 1 + if n in terminals: + self.log.warning("Token '%s' multiply defined", n) + terminals[n] = 1 + + # Get the literals specifier + def get_literals(self): + self.literals = self.ldict.get("literals","") + + # Validate literals + def validate_literals(self): + try: + for c in self.literals: + if not isinstance(c,StringTypes) or len(c) > 1: + self.log.error("Invalid literal %s. Must be a single character", repr(c)) + self.error = 1 + continue + + except TypeError: + self.log.error("Invalid literals specification. literals must be a sequence of characters") + self.error = 1 + + def get_states(self): + self.states = self.ldict.get("states",None) + # Build statemap + if self.states: + if not isinstance(self.states,(tuple,list)): + self.log.error("states must be defined as a tuple or list") + self.error = 1 + else: + for s in self.states: + if not isinstance(s,tuple) or len(s) != 2: + self.log.error("Invalid state specifier %s. Must be a tuple (statename,'exclusive|inclusive')",repr(s)) + self.error = 1 + continue + name, statetype = s + if not isinstance(name,StringTypes): + self.log.error("State name %s must be a string", repr(name)) + self.error = 1 + continue + if not (statetype == 'inclusive' or statetype == 'exclusive'): + self.log.error("State type for state %s must be 'inclusive' or 'exclusive'",name) + self.error = 1 + continue + if name in self.stateinfo: + self.log.error("State '%s' already defined",name) + self.error = 1 + continue + self.stateinfo[name] = statetype + + # Get all of the symbols with a t_ prefix and sort them into various + # categories (functions, strings, error functions, and ignore characters) + + def get_rules(self): + tsymbols = [f for f in self.ldict if f[:2] == 't_' ] + + # Now build up a list of functions and a list of strings + + self.toknames = { } # Mapping of symbols to token names + self.funcsym = { } # Symbols defined as functions + self.strsym = { } # Symbols defined as strings + self.ignore = { } # Ignore strings by state + self.errorf = { } # Error functions by state + + for s in self.stateinfo: + self.funcsym[s] = [] + self.strsym[s] = [] + + if len(tsymbols) == 0: + self.log.error("No rules of the form t_rulename are defined") + self.error = 1 + return + + for f in tsymbols: + t = self.ldict[f] + states, tokname = _statetoken(f,self.stateinfo) + self.toknames[f] = tokname + + if hasattr(t,"__call__"): + if tokname == 'error': + for s in states: + self.errorf[s] = t + elif tokname == 'ignore': + line = func_code(t).co_firstlineno + file = func_code(t).co_filename + self.log.error("%s:%d: Rule '%s' must be defined as a string",file,line,t.__name__) + self.error = 1 + else: + for s in states: + self.funcsym[s].append((f,t)) + elif isinstance(t, StringTypes): + if tokname == 'ignore': + for s in states: + self.ignore[s] = t + if "\\" in t: + self.log.warning("%s contains a literal backslash '\\'",f) + + elif tokname == 'error': + self.log.error("Rule '%s' must be defined as a function", f) + self.error = 1 + else: + for s in states: + self.strsym[s].append((f,t)) + else: + self.log.error("%s not defined as a function or string", f) + self.error = 1 + + # Sort the functions by line number + for f in self.funcsym.values(): + if sys.version_info[0] < 3: + f.sort(lambda x,y: cmp(func_code(x[1]).co_firstlineno,func_code(y[1]).co_firstlineno)) + else: + # Python 3.0 + f.sort(key=lambda x: func_code(x[1]).co_firstlineno) + + # Sort the strings by regular expression length + for s in self.strsym.values(): + if sys.version_info[0] < 3: + s.sort(lambda x,y: (len(x[1]) < len(y[1])) - (len(x[1]) > len(y[1]))) + else: + # Python 3.0 + s.sort(key=lambda x: len(x[1]),reverse=True) + + # Validate all of the t_rules collected + def validate_rules(self): + for state in self.stateinfo: + # Validate all rules defined by functions + + + + for fname, f in self.funcsym[state]: + line = func_code(f).co_firstlineno + file = func_code(f).co_filename + self.files[file] = 1 + + tokname = self.toknames[fname] + if isinstance(f, types.MethodType): + reqargs = 2 + else: + reqargs = 1 + nargs = func_code(f).co_argcount + if nargs > reqargs: + self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,f.__name__) + self.error = 1 + continue + + if nargs < reqargs: + self.log.error("%s:%d: Rule '%s' requires an argument", file,line,f.__name__) + self.error = 1 + continue + + if not f.__doc__: + self.log.error("%s:%d: No regular expression defined for rule '%s'",file,line,f.__name__) + self.error = 1 + continue + + try: + c = re.compile("(?P<%s>%s)" % (fname,f.__doc__), re.VERBOSE | self.reflags) + if c.match(""): + self.log.error("%s:%d: Regular expression for rule '%s' matches empty string", file,line,f.__name__) + self.error = 1 + except re.error: + _etype, e, _etrace = sys.exc_info() + self.log.error("%s:%d: Invalid regular expression for rule '%s'. %s", file,line,f.__name__,e) + if '#' in f.__doc__: + self.log.error("%s:%d. Make sure '#' in rule '%s' is escaped with '\\#'",file,line, f.__name__) + self.error = 1 + + # Validate all rules defined by strings + for name,r in self.strsym[state]: + tokname = self.toknames[name] + if tokname == 'error': + self.log.error("Rule '%s' must be defined as a function", name) + self.error = 1 + continue + + if not tokname in self.tokens and tokname.find("ignore_") < 0: + self.log.error("Rule '%s' defined for an unspecified token %s",name,tokname) + self.error = 1 + continue + + try: + c = re.compile("(?P<%s>%s)" % (name,r),re.VERBOSE | self.reflags) + if (c.match("")): + self.log.error("Regular expression for rule '%s' matches empty string",name) + self.error = 1 + except re.error: + _etype, e, _etrace = sys.exc_info() + self.log.error("Invalid regular expression for rule '%s'. %s",name,e) + if '#' in r: + self.log.error("Make sure '#' in rule '%s' is escaped with '\\#'",name) + self.error = 1 + + if not self.funcsym[state] and not self.strsym[state]: + self.log.error("No rules defined for state '%s'",state) + self.error = 1 + + # Validate the error function + efunc = self.errorf.get(state,None) + if efunc: + f = efunc + line = func_code(f).co_firstlineno + file = func_code(f).co_filename + self.files[file] = 1 + + if isinstance(f, types.MethodType): + reqargs = 2 + else: + reqargs = 1 + nargs = func_code(f).co_argcount + if nargs > reqargs: + self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,f.__name__) + self.error = 1 + + if nargs < reqargs: + self.log.error("%s:%d: Rule '%s' requires an argument", file,line,f.__name__) + self.error = 1 + + for f in self.files: + self.validate_file(f) + + + # ----------------------------------------------------------------------------- + # validate_file() + # + # This checks to see if there are duplicated t_rulename() functions or strings + # in the parser input file. This is done using a simple regular expression + # match on each line in the given file. + # ----------------------------------------------------------------------------- + + def validate_file(self,filename): + import os.path + base,ext = os.path.splitext(filename) + if ext != '.py': return # No idea what the file is. Return OK + + try: + f = open(filename) + lines = f.readlines() + f.close() + except IOError: + return # Couldn't find the file. Don't worry about it + + fre = re.compile(r'\s*def\s+(t_[a-zA-Z_0-9]*)\(') + sre = re.compile(r'\s*(t_[a-zA-Z_0-9]*)\s*=') + + counthash = { } + linen = 1 + for l in lines: + m = fre.match(l) + if not m: + m = sre.match(l) + if m: + name = m.group(1) + prev = counthash.get(name) + if not prev: + counthash[name] = linen + else: + self.log.error("%s:%d: Rule %s redefined. Previously defined on line %d",filename,linen,name,prev) + self.error = 1 + linen += 1 + +# ----------------------------------------------------------------------------- +# lex(module) +# +# Build all of the regular expression rules from definitions in the supplied module +# ----------------------------------------------------------------------------- +def lex(module=None,object=None,debug=0,optimize=0,lextab="lextab",reflags=0,nowarn=0,outputdir="", debuglog=None, errorlog=None): + global lexer + ldict = None + stateinfo = { 'INITIAL' : 'inclusive'} + lexobj = Lexer() + lexobj.lexoptimize = optimize + global token,input + + if errorlog is None: + errorlog = PlyLogger(sys.stderr) + + if debug: + if debuglog is None: + debuglog = PlyLogger(sys.stderr) + + # Get the module dictionary used for the lexer + if object: module = object + + if module: + _items = [(k,getattr(module,k)) for k in dir(module)] + ldict = dict(_items) + else: + ldict = get_caller_module_dict(2) + + # Collect parser information from the dictionary + linfo = LexerReflect(ldict,log=errorlog,reflags=reflags) + linfo.get_all() + if not optimize: + if linfo.validate_all(): + raise SyntaxError("Can't build lexer") + + if optimize and lextab: + try: + lexobj.readtab(lextab,ldict) + token = lexobj.token + input = lexobj.input + lexer = lexobj + return lexobj + + except ImportError: + pass + + # Dump some basic debugging information + if debug: + debuglog.info("lex: tokens = %r", linfo.tokens) + debuglog.info("lex: literals = %r", linfo.literals) + debuglog.info("lex: states = %r", linfo.stateinfo) + + # Build a dictionary of valid token names + lexobj.lextokens = { } + for n in linfo.tokens: + lexobj.lextokens[n] = 1 + + # Get literals specification + if isinstance(linfo.literals,(list,tuple)): + lexobj.lexliterals = type(linfo.literals[0])().join(linfo.literals) + else: + lexobj.lexliterals = linfo.literals + + # Get the stateinfo dictionary + stateinfo = linfo.stateinfo + + regexs = { } + # Build the master regular expressions + for state in stateinfo: + regex_list = [] + + # Add rules defined by functions first + for fname, f in linfo.funcsym[state]: + line = func_code(f).co_firstlineno + file = func_code(f).co_filename + regex_list.append("(?P<%s>%s)" % (fname,f.__doc__)) + if debug: + debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",fname,f.__doc__, state) + + # Now add all of the simple rules + for name,r in linfo.strsym[state]: + regex_list.append("(?P<%s>%s)" % (name,r)) + if debug: + debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",name,r, state) + + regexs[state] = regex_list + + # Build the master regular expressions + + if debug: + debuglog.info("lex: ==== MASTER REGEXS FOLLOW ====") + + for state in regexs: + lexre, re_text, re_names = _form_master_re(regexs[state],reflags,ldict,linfo.toknames) + lexobj.lexstatere[state] = lexre + lexobj.lexstateretext[state] = re_text + lexobj.lexstaterenames[state] = re_names + if debug: + for i in range(len(re_text)): + debuglog.info("lex: state '%s' : regex[%d] = '%s'",state, i, re_text[i]) + + # For inclusive states, we need to add the regular expressions from the INITIAL state + for state,stype in stateinfo.items(): + if state != "INITIAL" and stype == 'inclusive': + lexobj.lexstatere[state].extend(lexobj.lexstatere['INITIAL']) + lexobj.lexstateretext[state].extend(lexobj.lexstateretext['INITIAL']) + lexobj.lexstaterenames[state].extend(lexobj.lexstaterenames['INITIAL']) + + lexobj.lexstateinfo = stateinfo + lexobj.lexre = lexobj.lexstatere["INITIAL"] + lexobj.lexretext = lexobj.lexstateretext["INITIAL"] + lexobj.lexreflags = reflags + + # Set up ignore variables + lexobj.lexstateignore = linfo.ignore + lexobj.lexignore = lexobj.lexstateignore.get("INITIAL","") + + # Set up error functions + lexobj.lexstateerrorf = linfo.errorf + lexobj.lexerrorf = linfo.errorf.get("INITIAL",None) + if not lexobj.lexerrorf: + errorlog.warning("No t_error rule is defined") + + # Check state information for ignore and error rules + for s,stype in stateinfo.items(): + if stype == 'exclusive': + if not s in linfo.errorf: + errorlog.warning("No error rule is defined for exclusive state '%s'", s) + if not s in linfo.ignore and lexobj.lexignore: + errorlog.warning("No ignore rule is defined for exclusive state '%s'", s) + elif stype == 'inclusive': + if not s in linfo.errorf: + linfo.errorf[s] = linfo.errorf.get("INITIAL",None) + if not s in linfo.ignore: + linfo.ignore[s] = linfo.ignore.get("INITIAL","") + + # Create global versions of the token() and input() functions + token = lexobj.token + input = lexobj.input + lexer = lexobj + + # If in optimize mode, we write the lextab + if lextab and optimize: + lexobj.writetab(lextab,outputdir) + + return lexobj + +# ----------------------------------------------------------------------------- +# runmain() +# +# This runs the lexer as a main program +# ----------------------------------------------------------------------------- + +def runmain(lexer=None,data=None): + if not data: + try: + filename = sys.argv[1] + f = open(filename) + data = f.read() + f.close() + except IndexError: + sys.stdout.write("Reading from standard input (type EOF to end):\n") + data = sys.stdin.read() + + if lexer: + _input = lexer.input + else: + _input = input + _input(data) + if lexer: + _token = lexer.token + else: + _token = token + + while 1: + tok = _token() + if not tok: break + sys.stdout.write("(%s,%r,%d,%d)\n" % (tok.type, tok.value, tok.lineno,tok.lexpos)) + +# ----------------------------------------------------------------------------- +# @TOKEN(regex) +# +# This decorator function can be used to set the regex expression on a function +# when its docstring might need to be set in an alternative way +# ----------------------------------------------------------------------------- + +def TOKEN(r): + def set_doc(f): + if hasattr(r,"__call__"): + f.__doc__ = r.__doc__ + else: + f.__doc__ = r + return f + return set_doc + +# Alternative spelling of the TOKEN decorator +Token = TOKEN + diff --git a/third_party/ply/yacc.py b/third_party/ply/yacc.py new file mode 100644 index 0000000..e9f5c65 --- /dev/null +++ b/third_party/ply/yacc.py @@ -0,0 +1,3276 @@ +# ----------------------------------------------------------------------------- +# ply: yacc.py +# +# Copyright (C) 2001-2009, +# David M. Beazley (Dabeaz LLC) +# 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 the David Beazley or Dabeaz LLC 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. +# ----------------------------------------------------------------------------- +# +# This implements an LR parser that is constructed from grammar rules defined +# as Python functions. The grammer is specified by supplying the BNF inside +# Python documentation strings. The inspiration for this technique was borrowed +# from John Aycock's Spark parsing system. PLY might be viewed as cross between +# Spark and the GNU bison utility. +# +# The current implementation is only somewhat object-oriented. The +# LR parser itself is defined in terms of an object (which allows multiple +# parsers to co-exist). However, most of the variables used during table +# construction are defined in terms of global variables. Users shouldn't +# notice unless they are trying to define multiple parsers at the same +# time using threads (in which case they should have their head examined). +# +# This implementation supports both SLR and LALR(1) parsing. LALR(1) +# support was originally implemented by Elias Ioup (ezioup@alumni.uchicago.edu), +# using the algorithm found in Aho, Sethi, and Ullman "Compilers: Principles, +# Techniques, and Tools" (The Dragon Book). LALR(1) has since been replaced +# by the more efficient DeRemer and Pennello algorithm. +# +# :::::::: WARNING ::::::: +# +# Construction of LR parsing tables is fairly complicated and expensive. +# To make this module run fast, a *LOT* of work has been put into +# optimization---often at the expensive of readability and what might +# consider to be good Python "coding style." Modify the code at your +# own risk! +# ---------------------------------------------------------------------------- + +__version__ = "3.3" +__tabversion__ = "3.2" # Table version + +#----------------------------------------------------------------------------- +# === User configurable parameters === +# +# Change these to modify the default behavior of yacc (if you wish) +#----------------------------------------------------------------------------- + +yaccdebug = 1 # Debugging mode. If set, yacc generates a + # a 'parser.out' file in the current directory + +debug_file = 'parser.out' # Default name of the debugging file +tab_module = 'parsetab' # Default name of the table module +default_lr = 'LALR' # Default LR table generation method + +error_count = 3 # Number of symbols that must be shifted to leave recovery mode + +yaccdevel = 0 # Set to True if developing yacc. This turns off optimized + # implementations of certain functions. + +resultlimit = 40 # Size limit of results when running in debug mode. + +pickle_protocol = 0 # Protocol to use when writing pickle files + +import re, types, sys, os.path + +# Compatibility function for python 2.6/3.0 +if sys.version_info[0] < 3: + def func_code(f): + return f.func_code +else: + def func_code(f): + return f.__code__ + +# Compatibility +try: + MAXINT = sys.maxint +except AttributeError: + MAXINT = sys.maxsize + +# Python 2.x/3.0 compatibility. +def load_ply_lex(): + if sys.version_info[0] < 3: + import lex + else: + import ply.lex as lex + return lex + +# This object is a stand-in for a logging object created by the +# logging module. PLY will use this by default to create things +# such as the parser.out file. If a user wants more detailed +# information, they can create their own logging object and pass +# it into PLY. + +class PlyLogger(object): + def __init__(self,f): + self.f = f + def debug(self,msg,*args,**kwargs): + self.f.write((msg % args) + "\n") + info = debug + + def warning(self,msg,*args,**kwargs): + self.f.write("WARNING: "+ (msg % args) + "\n") + + def error(self,msg,*args,**kwargs): + self.f.write("ERROR: " + (msg % args) + "\n") + + critical = debug + +# Null logger is used when no output is generated. Does nothing. +class NullLogger(object): + def __getattribute__(self,name): + return self + def __call__(self,*args,**kwargs): + return self + +# Exception raised for yacc-related errors +class YaccError(Exception): pass + +# Format the result message that the parser produces when running in debug mode. +def format_result(r): + repr_str = repr(r) + if '\n' in repr_str: repr_str = repr(repr_str) + if len(repr_str) > resultlimit: + repr_str = repr_str[:resultlimit]+" ..." + result = "<%s @ 0x%x> (%s)" % (type(r).__name__,id(r),repr_str) + return result + + +# Format stack entries when the parser is running in debug mode +def format_stack_entry(r): + repr_str = repr(r) + if '\n' in repr_str: repr_str = repr(repr_str) + if len(repr_str) < 16: + return repr_str + else: + return "<%s @ 0x%x>" % (type(r).__name__,id(r)) + +#----------------------------------------------------------------------------- +# === LR Parsing Engine === +# +# The following classes are used for the LR parser itself. These are not +# used during table construction and are independent of the actual LR +# table generation algorithm +#----------------------------------------------------------------------------- + +# This class is used to hold non-terminal grammar symbols during parsing. +# It normally has the following attributes set: +# .type = Grammar symbol type +# .value = Symbol value +# .lineno = Starting line number +# .endlineno = Ending line number (optional, set automatically) +# .lexpos = Starting lex position +# .endlexpos = Ending lex position (optional, set automatically) + +class YaccSymbol: + def __str__(self): return self.type + def __repr__(self): return str(self) + +# This class is a wrapper around the objects actually passed to each +# grammar rule. Index lookup and assignment actually assign the +# .value attribute of the underlying YaccSymbol object. +# The lineno() method returns the line number of a given +# item (or 0 if not defined). The linespan() method returns +# a tuple of (startline,endline) representing the range of lines +# for a symbol. The lexspan() method returns a tuple (lexpos,endlexpos) +# representing the range of positional information for a symbol. + +class YaccProduction: + def __init__(self,s,stack=None): + self.slice = s + self.stack = stack + self.lexer = None + self.parser= None + def __getitem__(self,n): + if n >= 0: return self.slice[n].value + else: return self.stack[n].value + + def __setitem__(self,n,v): + self.slice[n].value = v + + def __getslice__(self,i,j): + return [s.value for s in self.slice[i:j]] + + def __len__(self): + return len(self.slice) + + def lineno(self,n): + return getattr(self.slice[n],"lineno",0) + + def set_lineno(self,n,lineno): + self.slice[n].lineno = lineno + + def linespan(self,n): + startline = getattr(self.slice[n],"lineno",0) + endline = getattr(self.slice[n],"endlineno",startline) + return startline,endline + + def lexpos(self,n): + return getattr(self.slice[n],"lexpos",0) + + def lexspan(self,n): + startpos = getattr(self.slice[n],"lexpos",0) + endpos = getattr(self.slice[n],"endlexpos",startpos) + return startpos,endpos + + def error(self): + raise SyntaxError + + +# ----------------------------------------------------------------------------- +# == LRParser == +# +# The LR Parsing engine. +# ----------------------------------------------------------------------------- + +class LRParser: + def __init__(self,lrtab,errorf): + self.productions = lrtab.lr_productions + self.action = lrtab.lr_action + self.goto = lrtab.lr_goto + self.errorfunc = errorf + + def errok(self): + self.errorok = 1 + + def restart(self): + del self.statestack[:] + del self.symstack[:] + sym = YaccSymbol() + sym.type = '$end' + self.symstack.append(sym) + self.statestack.append(0) + + def parse(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None): + if debug or yaccdevel: + if isinstance(debug,int): + debug = PlyLogger(sys.stderr) + return self.parsedebug(input,lexer,debug,tracking,tokenfunc) + elif tracking: + return self.parseopt(input,lexer,debug,tracking,tokenfunc) + else: + return self.parseopt_notrack(input,lexer,debug,tracking,tokenfunc) + + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # parsedebug(). + # + # This is the debugging enabled version of parse(). All changes made to the + # parsing engine should be made here. For the non-debugging version, + # copy this code to a method parseopt() and delete all of the sections + # enclosed in: + # + # #--! DEBUG + # statements + # #--! DEBUG + # + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + def parsedebug(self,input=None,lexer=None,debug=None,tracking=0,tokenfunc=None): + lookahead = None # Current lookahead symbol + lookaheadstack = [ ] # Stack of lookahead symbols + actions = self.action # Local reference to action table (to avoid lookup on self.) + goto = self.goto # Local reference to goto table (to avoid lookup on self.) + prod = self.productions # Local reference to production list (to avoid lookup on self.) + pslice = YaccProduction(None) # Production object passed to grammar rules + errorcount = 0 # Used during error recovery + + # --! DEBUG + debug.info("PLY: PARSE DEBUG START") + # --! DEBUG + + # If no lexer was given, we will try to use the lex module + if not lexer: + lex = load_ply_lex() + lexer = lex.lexer + + # Set up the lexer and parser objects on pslice + pslice.lexer = lexer + pslice.parser = self + + # If input was supplied, pass to lexer + if input is not None: + lexer.input(input) + + if tokenfunc is None: + # Tokenize function + get_token = lexer.token + else: + get_token = tokenfunc + + # Set up the state and symbol stacks + + statestack = [ ] # Stack of parsing states + self.statestack = statestack + symstack = [ ] # Stack of grammar symbols + self.symstack = symstack + + pslice.stack = symstack # Put in the production + errtoken = None # Err token + + # The start state is assumed to be (0,$end) + + statestack.append(0) + sym = YaccSymbol() + sym.type = "$end" + symstack.append(sym) + state = 0 + while 1: + # Get the next symbol on the input. If a lookahead symbol + # is already set, we just use that. Otherwise, we'll pull + # the next token off of the lookaheadstack or from the lexer + + # --! DEBUG + debug.debug('') + debug.debug('State : %s', state) + # --! DEBUG + + if not lookahead: + if not lookaheadstack: + lookahead = get_token() # Get the next token + else: + lookahead = lookaheadstack.pop() + if not lookahead: + lookahead = YaccSymbol() + lookahead.type = "$end" + + # --! DEBUG + debug.debug('Stack : %s', + ("%s . %s" % (" ".join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip()) + # --! DEBUG + + # Check the action table + ltype = lookahead.type + t = actions[state].get(ltype) + + if t is not None: + if t > 0: + # shift a symbol on the stack + statestack.append(t) + state = t + + # --! DEBUG + debug.debug("Action : Shift and goto state %s", t) + # --! DEBUG + + symstack.append(lookahead) + lookahead = None + + # Decrease error count on successful shift + if errorcount: errorcount -=1 + continue + + if t < 0: + # reduce a symbol on the stack, emit a production + p = prod[-t] + pname = p.name + plen = p.len + + # Get production function + sym = YaccSymbol() + sym.type = pname # Production name + sym.value = None + + # --! DEBUG + if plen: + debug.info("Action : Reduce rule [%s] with %s and goto state %d", p.str, "["+",".join([format_stack_entry(_v.value) for _v in symstack[-plen:]])+"]",-t) + else: + debug.info("Action : Reduce rule [%s] with %s and goto state %d", p.str, [],-t) + + # --! DEBUG + + if plen: + targ = symstack[-plen-1:] + targ[0] = sym + + # --! TRACKING + if tracking: + t1 = targ[1] + sym.lineno = t1.lineno + sym.lexpos = t1.lexpos + t1 = targ[-1] + sym.endlineno = getattr(t1,"endlineno",t1.lineno) + sym.endlexpos = getattr(t1,"endlexpos",t1.lexpos) + + # --! TRACKING + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # The code enclosed in this section is duplicated + # below as a performance optimization. Make sure + # changes get made in both locations. + + pslice.slice = targ + + try: + # Call the grammar rule with our special slice object + del symstack[-plen:] + del statestack[-plen:] + p.callable(pslice) + # --! DEBUG + debug.info("Result : %s", format_result(pslice[0])) + # --! DEBUG + symstack.append(sym) + state = goto[statestack[-1]][pname] + statestack.append(state) + except SyntaxError: + # If an error was set. Enter error recovery state + lookaheadstack.append(lookahead) + symstack.pop() + statestack.pop() + state = statestack[-1] + sym.type = 'error' + lookahead = sym + errorcount = error_count + self.errorok = 0 + continue + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + else: + + # --! TRACKING + if tracking: + sym.lineno = lexer.lineno + sym.lexpos = lexer.lexpos + # --! TRACKING + + targ = [ sym ] + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # The code enclosed in this section is duplicated + # above as a performance optimization. Make sure + # changes get made in both locations. + + pslice.slice = targ + + try: + # Call the grammar rule with our special slice object + p.callable(pslice) + # --! DEBUG + debug.info("Result : %s", format_result(pslice[0])) + # --! DEBUG + symstack.append(sym) + state = goto[statestack[-1]][pname] + statestack.append(state) + except SyntaxError: + # If an error was set. Enter error recovery state + lookaheadstack.append(lookahead) + symstack.pop() + statestack.pop() + state = statestack[-1] + sym.type = 'error' + lookahead = sym + errorcount = error_count + self.errorok = 0 + continue + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + if t == 0: + n = symstack[-1] + result = getattr(n,"value",None) + # --! DEBUG + debug.info("Done : Returning %s", format_result(result)) + debug.info("PLY: PARSE DEBUG END") + # --! DEBUG + return result + + if t == None: + + # --! DEBUG + debug.error('Error : %s', + ("%s . %s" % (" ".join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip()) + # --! DEBUG + + # We have some kind of parsing error here. To handle + # this, we are going to push the current token onto + # the tokenstack and replace it with an 'error' token. + # If there are any synchronization rules, they may + # catch it. + # + # In addition to pushing the error token, we call call + # the user defined p_error() function if this is the + # first syntax error. This function is only called if + # errorcount == 0. + if errorcount == 0 or self.errorok: + errorcount = error_count + self.errorok = 0 + errtoken = lookahead + if errtoken.type == "$end": + errtoken = None # End of file! + if self.errorfunc: + global errok,token,restart + errok = self.errok # Set some special functions available in error recovery + token = get_token + restart = self.restart + if errtoken and not hasattr(errtoken,'lexer'): + errtoken.lexer = lexer + tok = self.errorfunc(errtoken) + del errok, token, restart # Delete special functions + + if self.errorok: + # User must have done some kind of panic + # mode recovery on their own. The + # returned token is the next lookahead + lookahead = tok + errtoken = None + continue + else: + if errtoken: + if hasattr(errtoken,"lineno"): lineno = lookahead.lineno + else: lineno = 0 + if lineno: + sys.stderr.write("yacc: Syntax error at line %d, token=%s\n" % (lineno, errtoken.type)) + else: + sys.stderr.write("yacc: Syntax error, token=%s" % errtoken.type) + else: + sys.stderr.write("yacc: Parse error in input. EOF\n") + return + + else: + errorcount = error_count + + # case 1: the statestack only has 1 entry on it. If we're in this state, the + # entire parse has been rolled back and we're completely hosed. The token is + # discarded and we just keep going. + + if len(statestack) <= 1 and lookahead.type != "$end": + lookahead = None + errtoken = None + state = 0 + # Nuke the pushback stack + del lookaheadstack[:] + continue + + # case 2: the statestack has a couple of entries on it, but we're + # at the end of the file. nuke the top entry and generate an error token + + # Start nuking entries on the stack + if lookahead.type == "$end": + # Whoa. We're really hosed here. Bail out + return + + if lookahead.type != 'error': + sym = symstack[-1] + if sym.type == 'error': + # Hmmm. Error is on top of stack, we'll just nuke input + # symbol and continue + lookahead = None + continue + t = YaccSymbol() + t.type = 'error' + if hasattr(lookahead,"lineno"): + t.lineno = lookahead.lineno + t.value = lookahead + lookaheadstack.append(lookahead) + lookahead = t + else: + symstack.pop() + statestack.pop() + state = statestack[-1] # Potential bug fix + + continue + + # Call an error function here + raise RuntimeError("yacc: internal parser error!!!\n") + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # parseopt(). + # + # Optimized version of parse() method. DO NOT EDIT THIS CODE DIRECTLY. + # Edit the debug version above, then copy any modifications to the method + # below while removing #--! DEBUG sections. + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + + def parseopt(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None): + lookahead = None # Current lookahead symbol + lookaheadstack = [ ] # Stack of lookahead symbols + actions = self.action # Local reference to action table (to avoid lookup on self.) + goto = self.goto # Local reference to goto table (to avoid lookup on self.) + prod = self.productions # Local reference to production list (to avoid lookup on self.) + pslice = YaccProduction(None) # Production object passed to grammar rules + errorcount = 0 # Used during error recovery + + # If no lexer was given, we will try to use the lex module + if not lexer: + lex = load_ply_lex() + lexer = lex.lexer + + # Set up the lexer and parser objects on pslice + pslice.lexer = lexer + pslice.parser = self + + # If input was supplied, pass to lexer + if input is not None: + lexer.input(input) + + if tokenfunc is None: + # Tokenize function + get_token = lexer.token + else: + get_token = tokenfunc + + # Set up the state and symbol stacks + + statestack = [ ] # Stack of parsing states + self.statestack = statestack + symstack = [ ] # Stack of grammar symbols + self.symstack = symstack + + pslice.stack = symstack # Put in the production + errtoken = None # Err token + + # The start state is assumed to be (0,$end) + + statestack.append(0) + sym = YaccSymbol() + sym.type = '$end' + symstack.append(sym) + state = 0 + while 1: + # Get the next symbol on the input. If a lookahead symbol + # is already set, we just use that. Otherwise, we'll pull + # the next token off of the lookaheadstack or from the lexer + + if not lookahead: + if not lookaheadstack: + lookahead = get_token() # Get the next token + else: + lookahead = lookaheadstack.pop() + if not lookahead: + lookahead = YaccSymbol() + lookahead.type = '$end' + + # Check the action table + ltype = lookahead.type + t = actions[state].get(ltype) + + if t is not None: + if t > 0: + # shift a symbol on the stack + statestack.append(t) + state = t + + symstack.append(lookahead) + lookahead = None + + # Decrease error count on successful shift + if errorcount: errorcount -=1 + continue + + if t < 0: + # reduce a symbol on the stack, emit a production + p = prod[-t] + pname = p.name + plen = p.len + + # Get production function + sym = YaccSymbol() + sym.type = pname # Production name + sym.value = None + + if plen: + targ = symstack[-plen-1:] + targ[0] = sym + + # --! TRACKING + if tracking: + t1 = targ[1] + sym.lineno = t1.lineno + sym.lexpos = t1.lexpos + t1 = targ[-1] + sym.endlineno = getattr(t1,"endlineno",t1.lineno) + sym.endlexpos = getattr(t1,"endlexpos",t1.lexpos) + + # --! TRACKING + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # The code enclosed in this section is duplicated + # below as a performance optimization. Make sure + # changes get made in both locations. + + pslice.slice = targ + + try: + # Call the grammar rule with our special slice object + del symstack[-plen:] + del statestack[-plen:] + p.callable(pslice) + symstack.append(sym) + state = goto[statestack[-1]][pname] + statestack.append(state) + except SyntaxError: + # If an error was set. Enter error recovery state + lookaheadstack.append(lookahead) + symstack.pop() + statestack.pop() + state = statestack[-1] + sym.type = 'error' + lookahead = sym + errorcount = error_count + self.errorok = 0 + continue + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + else: + + # --! TRACKING + if tracking: + sym.lineno = lexer.lineno + sym.lexpos = lexer.lexpos + # --! TRACKING + + targ = [ sym ] + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # The code enclosed in this section is duplicated + # above as a performance optimization. Make sure + # changes get made in both locations. + + pslice.slice = targ + + try: + # Call the grammar rule with our special slice object + p.callable(pslice) + symstack.append(sym) + state = goto[statestack[-1]][pname] + statestack.append(state) + except SyntaxError: + # If an error was set. Enter error recovery state + lookaheadstack.append(lookahead) + symstack.pop() + statestack.pop() + state = statestack[-1] + sym.type = 'error' + lookahead = sym + errorcount = error_count + self.errorok = 0 + continue + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + if t == 0: + n = symstack[-1] + return getattr(n,"value",None) + + if t == None: + + # We have some kind of parsing error here. To handle + # this, we are going to push the current token onto + # the tokenstack and replace it with an 'error' token. + # If there are any synchronization rules, they may + # catch it. + # + # In addition to pushing the error token, we call call + # the user defined p_error() function if this is the + # first syntax error. This function is only called if + # errorcount == 0. + if errorcount == 0 or self.errorok: + errorcount = error_count + self.errorok = 0 + errtoken = lookahead + if errtoken.type == '$end': + errtoken = None # End of file! + if self.errorfunc: + global errok,token,restart + errok = self.errok # Set some special functions available in error recovery + token = get_token + restart = self.restart + if errtoken and not hasattr(errtoken,'lexer'): + errtoken.lexer = lexer + tok = self.errorfunc(errtoken) + del errok, token, restart # Delete special functions + + if self.errorok: + # User must have done some kind of panic + # mode recovery on their own. The + # returned token is the next lookahead + lookahead = tok + errtoken = None + continue + else: + if errtoken: + if hasattr(errtoken,"lineno"): lineno = lookahead.lineno + else: lineno = 0 + if lineno: + sys.stderr.write("yacc: Syntax error at line %d, token=%s\n" % (lineno, errtoken.type)) + else: + sys.stderr.write("yacc: Syntax error, token=%s" % errtoken.type) + else: + sys.stderr.write("yacc: Parse error in input. EOF\n") + return + + else: + errorcount = error_count + + # case 1: the statestack only has 1 entry on it. If we're in this state, the + # entire parse has been rolled back and we're completely hosed. The token is + # discarded and we just keep going. + + if len(statestack) <= 1 and lookahead.type != '$end': + lookahead = None + errtoken = None + state = 0 + # Nuke the pushback stack + del lookaheadstack[:] + continue + + # case 2: the statestack has a couple of entries on it, but we're + # at the end of the file. nuke the top entry and generate an error token + + # Start nuking entries on the stack + if lookahead.type == '$end': + # Whoa. We're really hosed here. Bail out + return + + if lookahead.type != 'error': + sym = symstack[-1] + if sym.type == 'error': + # Hmmm. Error is on top of stack, we'll just nuke input + # symbol and continue + lookahead = None + continue + t = YaccSymbol() + t.type = 'error' + if hasattr(lookahead,"lineno"): + t.lineno = lookahead.lineno + t.value = lookahead + lookaheadstack.append(lookahead) + lookahead = t + else: + symstack.pop() + statestack.pop() + state = statestack[-1] # Potential bug fix + + continue + + # Call an error function here + raise RuntimeError("yacc: internal parser error!!!\n") + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # parseopt_notrack(). + # + # Optimized version of parseopt() with line number tracking removed. + # DO NOT EDIT THIS CODE DIRECTLY. Copy the optimized version and remove + # code in the #--! TRACKING sections + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + def parseopt_notrack(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None): + lookahead = None # Current lookahead symbol + lookaheadstack = [ ] # Stack of lookahead symbols + actions = self.action # Local reference to action table (to avoid lookup on self.) + goto = self.goto # Local reference to goto table (to avoid lookup on self.) + prod = self.productions # Local reference to production list (to avoid lookup on self.) + pslice = YaccProduction(None) # Production object passed to grammar rules + errorcount = 0 # Used during error recovery + + # If no lexer was given, we will try to use the lex module + if not lexer: + lex = load_ply_lex() + lexer = lex.lexer + + # Set up the lexer and parser objects on pslice + pslice.lexer = lexer + pslice.parser = self + + # If input was supplied, pass to lexer + if input is not None: + lexer.input(input) + + if tokenfunc is None: + # Tokenize function + get_token = lexer.token + else: + get_token = tokenfunc + + # Set up the state and symbol stacks + + statestack = [ ] # Stack of parsing states + self.statestack = statestack + symstack = [ ] # Stack of grammar symbols + self.symstack = symstack + + pslice.stack = symstack # Put in the production + errtoken = None # Err token + + # The start state is assumed to be (0,$end) + + statestack.append(0) + sym = YaccSymbol() + sym.type = '$end' + symstack.append(sym) + state = 0 + while 1: + # Get the next symbol on the input. If a lookahead symbol + # is already set, we just use that. Otherwise, we'll pull + # the next token off of the lookaheadstack or from the lexer + + if not lookahead: + if not lookaheadstack: + lookahead = get_token() # Get the next token + else: + lookahead = lookaheadstack.pop() + if not lookahead: + lookahead = YaccSymbol() + lookahead.type = '$end' + + # Check the action table + ltype = lookahead.type + t = actions[state].get(ltype) + + if t is not None: + if t > 0: + # shift a symbol on the stack + statestack.append(t) + state = t + + symstack.append(lookahead) + lookahead = None + + # Decrease error count on successful shift + if errorcount: errorcount -=1 + continue + + if t < 0: + # reduce a symbol on the stack, emit a production + p = prod[-t] + pname = p.name + plen = p.len + + # Get production function + sym = YaccSymbol() + sym.type = pname # Production name + sym.value = None + + if plen: + targ = symstack[-plen-1:] + targ[0] = sym + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # The code enclosed in this section is duplicated + # below as a performance optimization. Make sure + # changes get made in both locations. + + pslice.slice = targ + + try: + # Call the grammar rule with our special slice object + del symstack[-plen:] + del statestack[-plen:] + p.callable(pslice) + symstack.append(sym) + state = goto[statestack[-1]][pname] + statestack.append(state) + except SyntaxError: + # If an error was set. Enter error recovery state + lookaheadstack.append(lookahead) + symstack.pop() + statestack.pop() + state = statestack[-1] + sym.type = 'error' + lookahead = sym + errorcount = error_count + self.errorok = 0 + continue + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + else: + + targ = [ sym ] + + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + # The code enclosed in this section is duplicated + # above as a performance optimization. Make sure + # changes get made in both locations. + + pslice.slice = targ + + try: + # Call the grammar rule with our special slice object + p.callable(pslice) + symstack.append(sym) + state = goto[statestack[-1]][pname] + statestack.append(state) + except SyntaxError: + # If an error was set. Enter error recovery state + lookaheadstack.append(lookahead) + symstack.pop() + statestack.pop() + state = statestack[-1] + sym.type = 'error' + lookahead = sym + errorcount = error_count + self.errorok = 0 + continue + # !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + + if t == 0: + n = symstack[-1] + return getattr(n,"value",None) + + if t == None: + + # We have some kind of parsing error here. To handle + # this, we are going to push the current token onto + # the tokenstack and replace it with an 'error' token. + # If there are any synchronization rules, they may + # catch it. + # + # In addition to pushing the error token, we call call + # the user defined p_error() function if this is the + # first syntax error. This function is only called if + # errorcount == 0. + if errorcount == 0 or self.errorok: + errorcount = error_count + self.errorok = 0 + errtoken = lookahead + if errtoken.type == '$end': + errtoken = None # End of file! + if self.errorfunc: + global errok,token,restart + errok = self.errok # Set some special functions available in error recovery + token = get_token + restart = self.restart + if errtoken and not hasattr(errtoken,'lexer'): + errtoken.lexer = lexer + tok = self.errorfunc(errtoken) + del errok, token, restart # Delete special functions + + if self.errorok: + # User must have done some kind of panic + # mode recovery on their own. The + # returned token is the next lookahead + lookahead = tok + errtoken = None + continue + else: + if errtoken: + if hasattr(errtoken,"lineno"): lineno = lookahead.lineno + else: lineno = 0 + if lineno: + sys.stderr.write("yacc: Syntax error at line %d, token=%s\n" % (lineno, errtoken.type)) + else: + sys.stderr.write("yacc: Syntax error, token=%s" % errtoken.type) + else: + sys.stderr.write("yacc: Parse error in input. EOF\n") + return + + else: + errorcount = error_count + + # case 1: the statestack only has 1 entry on it. If we're in this state, the + # entire parse has been rolled back and we're completely hosed. The token is + # discarded and we just keep going. + + if len(statestack) <= 1 and lookahead.type != '$end': + lookahead = None + errtoken = None + state = 0 + # Nuke the pushback stack + del lookaheadstack[:] + continue + + # case 2: the statestack has a couple of entries on it, but we're + # at the end of the file. nuke the top entry and generate an error token + + # Start nuking entries on the stack + if lookahead.type == '$end': + # Whoa. We're really hosed here. Bail out + return + + if lookahead.type != 'error': + sym = symstack[-1] + if sym.type == 'error': + # Hmmm. Error is on top of stack, we'll just nuke input + # symbol and continue + lookahead = None + continue + t = YaccSymbol() + t.type = 'error' + if hasattr(lookahead,"lineno"): + t.lineno = lookahead.lineno + t.value = lookahead + lookaheadstack.append(lookahead) + lookahead = t + else: + symstack.pop() + statestack.pop() + state = statestack[-1] # Potential bug fix + + continue + + # Call an error function here + raise RuntimeError("yacc: internal parser error!!!\n") + +# ----------------------------------------------------------------------------- +# === Grammar Representation === +# +# The following functions, classes, and variables are used to represent and +# manipulate the rules that make up a grammar. +# ----------------------------------------------------------------------------- + +import re + +# regex matching identifiers +_is_identifier = re.compile(r'^[a-zA-Z0-9_-]+$') + +# ----------------------------------------------------------------------------- +# class Production: +# +# This class stores the raw information about a single production or grammar rule. +# A grammar rule refers to a specification such as this: +# +# expr : expr PLUS term +# +# Here are the basic attributes defined on all productions +# +# name - Name of the production. For example 'expr' +# prod - A list of symbols on the right side ['expr','PLUS','term'] +# prec - Production precedence level +# number - Production number. +# func - Function that executes on reduce +# file - File where production function is defined +# lineno - Line number where production function is defined +# +# The following attributes are defined or optional. +# +# len - Length of the production (number of symbols on right hand side) +# usyms - Set of unique symbols found in the production +# ----------------------------------------------------------------------------- + +class Production(object): + reduced = 0 + def __init__(self,number,name,prod,precedence=('right',0),func=None,file='',line=0): + self.name = name + self.prod = tuple(prod) + self.number = number + self.func = func + self.callable = None + self.file = file + self.line = line + self.prec = precedence + + # Internal settings used during table construction + + self.len = len(self.prod) # Length of the production + + # Create a list of unique production symbols used in the production + self.usyms = [ ] + for s in self.prod: + if s not in self.usyms: + self.usyms.append(s) + + # List of all LR items for the production + self.lr_items = [] + self.lr_next = None + + # Create a string representation + if self.prod: + self.str = "%s -> %s" % (self.name," ".join(self.prod)) + else: + self.str = "%s -> <empty>" % self.name + + def __str__(self): + return self.str + + def __repr__(self): + return "Production("+str(self)+")" + + def __len__(self): + return len(self.prod) + + def __nonzero__(self): + return 1 + + def __getitem__(self,index): + return self.prod[index] + + # Return the nth lr_item from the production (or None if at the end) + def lr_item(self,n): + if n > len(self.prod): return None + p = LRItem(self,n) + + # Precompute the list of productions immediately following. Hack. Remove later + try: + p.lr_after = Prodnames[p.prod[n+1]] + except (IndexError,KeyError): + p.lr_after = [] + try: + p.lr_before = p.prod[n-1] + except IndexError: + p.lr_before = None + + return p + + # Bind the production function name to a callable + def bind(self,pdict): + if self.func: + self.callable = pdict[self.func] + +# This class serves as a minimal standin for Production objects when +# reading table data from files. It only contains information +# actually used by the LR parsing engine, plus some additional +# debugging information. +class MiniProduction(object): + def __init__(self,str,name,len,func,file,line): + self.name = name + self.len = len + self.func = func + self.callable = None + self.file = file + self.line = line + self.str = str + def __str__(self): + return self.str + def __repr__(self): + return "MiniProduction(%s)" % self.str + + # Bind the production function name to a callable + def bind(self,pdict): + if self.func: + self.callable = pdict[self.func] + + +# ----------------------------------------------------------------------------- +# class LRItem +# +# This class represents a specific stage of parsing a production rule. For +# example: +# +# expr : expr . PLUS term +# +# In the above, the "." represents the current location of the parse. Here +# basic attributes: +# +# name - Name of the production. For example 'expr' +# prod - A list of symbols on the right side ['expr','.', 'PLUS','term'] +# number - Production number. +# +# lr_next Next LR item. Example, if we are ' expr -> expr . PLUS term' +# then lr_next refers to 'expr -> expr PLUS . term' +# lr_index - LR item index (location of the ".") in the prod list. +# lookaheads - LALR lookahead symbols for this item +# len - Length of the production (number of symbols on right hand side) +# lr_after - List of all productions that immediately follow +# lr_before - Grammar symbol immediately before +# ----------------------------------------------------------------------------- + +class LRItem(object): + def __init__(self,p,n): + self.name = p.name + self.prod = list(p.prod) + self.number = p.number + self.lr_index = n + self.lookaheads = { } + self.prod.insert(n,".") + self.prod = tuple(self.prod) + self.len = len(self.prod) + self.usyms = p.usyms + + def __str__(self): + if self.prod: + s = "%s -> %s" % (self.name," ".join(self.prod)) + else: + s = "%s -> <empty>" % self.name + return s + + def __repr__(self): + return "LRItem("+str(self)+")" + +# ----------------------------------------------------------------------------- +# rightmost_terminal() +# +# Return the rightmost terminal from a list of symbols. Used in add_production() +# ----------------------------------------------------------------------------- +def rightmost_terminal(symbols, terminals): + i = len(symbols) - 1 + while i >= 0: + if symbols[i] in terminals: + return symbols[i] + i -= 1 + return None + +# ----------------------------------------------------------------------------- +# === GRAMMAR CLASS === +# +# The following class represents the contents of the specified grammar along +# with various computed properties such as first sets, follow sets, LR items, etc. +# This data is used for critical parts of the table generation process later. +# ----------------------------------------------------------------------------- + +class GrammarError(YaccError): pass + +class Grammar(object): + def __init__(self,terminals): + self.Productions = [None] # A list of all of the productions. The first + # entry is always reserved for the purpose of + # building an augmented grammar + + self.Prodnames = { } # A dictionary mapping the names of nonterminals to a list of all + # productions of that nonterminal. + + self.Prodmap = { } # A dictionary that is only used to detect duplicate + # productions. + + self.Terminals = { } # A dictionary mapping the names of terminal symbols to a + # list of the rules where they are used. + + for term in terminals: + self.Terminals[term] = [] + + self.Terminals['error'] = [] + + self.Nonterminals = { } # A dictionary mapping names of nonterminals to a list + # of rule numbers where they are used. + + self.First = { } # A dictionary of precomputed FIRST(x) symbols + + self.Follow = { } # A dictionary of precomputed FOLLOW(x) symbols + + self.Precedence = { } # Precedence rules for each terminal. Contains tuples of the + # form ('right',level) or ('nonassoc', level) or ('left',level) + + self.UsedPrecedence = { } # Precedence rules that were actually used by the grammer. + # This is only used to provide error checking and to generate + # a warning about unused precedence rules. + + self.Start = None # Starting symbol for the grammar + + + def __len__(self): + return len(self.Productions) + + def __getitem__(self,index): + return self.Productions[index] + + # ----------------------------------------------------------------------------- + # set_precedence() + # + # Sets the precedence for a given terminal. assoc is the associativity such as + # 'left','right', or 'nonassoc'. level is a numeric level. + # + # ----------------------------------------------------------------------------- + + def set_precedence(self,term,assoc,level): + assert self.Productions == [None],"Must call set_precedence() before add_production()" + if term in self.Precedence: + raise GrammarError("Precedence already specified for terminal '%s'" % term) + if assoc not in ['left','right','nonassoc']: + raise GrammarError("Associativity must be one of 'left','right', or 'nonassoc'") + self.Precedence[term] = (assoc,level) + + # ----------------------------------------------------------------------------- + # add_production() + # + # Given an action function, this function assembles a production rule and + # computes its precedence level. + # + # The production rule is supplied as a list of symbols. For example, + # a rule such as 'expr : expr PLUS term' has a production name of 'expr' and + # symbols ['expr','PLUS','term']. + # + # Precedence is determined by the precedence of the right-most non-terminal + # or the precedence of a terminal specified by %prec. + # + # A variety of error checks are performed to make sure production symbols + # are valid and that %prec is used correctly. + # ----------------------------------------------------------------------------- + + def add_production(self,prodname,syms,func=None,file='',line=0): + + if prodname in self.Terminals: + raise GrammarError("%s:%d: Illegal rule name '%s'. Already defined as a token" % (file,line,prodname)) + if prodname == 'error': + raise GrammarError("%s:%d: Illegal rule name '%s'. error is a reserved word" % (file,line,prodname)) + if not _is_identifier.match(prodname): + raise GrammarError("%s:%d: Illegal rule name '%s'" % (file,line,prodname)) + + # Look for literal tokens + for n,s in enumerate(syms): + if s[0] in "'\"": + try: + c = eval(s) + if (len(c) > 1): + raise GrammarError("%s:%d: Literal token %s in rule '%s' may only be a single character" % (file,line,s, prodname)) + if not c in self.Terminals: + self.Terminals[c] = [] + syms[n] = c + continue + except SyntaxError: + pass + if not _is_identifier.match(s) and s != '%prec': + raise GrammarError("%s:%d: Illegal name '%s' in rule '%s'" % (file,line,s, prodname)) + + # Determine the precedence level + if '%prec' in syms: + if syms[-1] == '%prec': + raise GrammarError("%s:%d: Syntax error. Nothing follows %%prec" % (file,line)) + if syms[-2] != '%prec': + raise GrammarError("%s:%d: Syntax error. %%prec can only appear at the end of a grammar rule" % (file,line)) + precname = syms[-1] + prodprec = self.Precedence.get(precname,None) + if not prodprec: + raise GrammarError("%s:%d: Nothing known about the precedence of '%s'" % (file,line,precname)) + else: + self.UsedPrecedence[precname] = 1 + del syms[-2:] # Drop %prec from the rule + else: + # If no %prec, precedence is determined by the rightmost terminal symbol + precname = rightmost_terminal(syms,self.Terminals) + prodprec = self.Precedence.get(precname,('right',0)) + + # See if the rule is already in the rulemap + map = "%s -> %s" % (prodname,syms) + if map in self.Prodmap: + m = self.Prodmap[map] + raise GrammarError("%s:%d: Duplicate rule %s. " % (file,line, m) + + "Previous definition at %s:%d" % (m.file, m.line)) + + # From this point on, everything is valid. Create a new Production instance + pnumber = len(self.Productions) + if not prodname in self.Nonterminals: + self.Nonterminals[prodname] = [ ] + + # Add the production number to Terminals and Nonterminals + for t in syms: + if t in self.Terminals: + self.Terminals[t].append(pnumber) + else: + if not t in self.Nonterminals: + self.Nonterminals[t] = [ ] + self.Nonterminals[t].append(pnumber) + + # Create a production and add it to the list of productions + p = Production(pnumber,prodname,syms,prodprec,func,file,line) + self.Productions.append(p) + self.Prodmap[map] = p + + # Add to the global productions list + try: + self.Prodnames[prodname].append(p) + except KeyError: + self.Prodnames[prodname] = [ p ] + return 0 + + # ----------------------------------------------------------------------------- + # set_start() + # + # Sets the starting symbol and creates the augmented grammar. Production + # rule 0 is S' -> start where start is the start symbol. + # ----------------------------------------------------------------------------- + + def set_start(self,start=None): + if not start: + start = self.Productions[1].name + if start not in self.Nonterminals: + raise GrammarError("start symbol %s undefined" % start) + self.Productions[0] = Production(0,"S'",[start]) + self.Nonterminals[start].append(0) + self.Start = start + + # ----------------------------------------------------------------------------- + # find_unreachable() + # + # Find all of the nonterminal symbols that can't be reached from the starting + # symbol. Returns a list of nonterminals that can't be reached. + # ----------------------------------------------------------------------------- + + def find_unreachable(self): + + # Mark all symbols that are reachable from a symbol s + def mark_reachable_from(s): + if reachable[s]: + # We've already reached symbol s. + return + reachable[s] = 1 + for p in self.Prodnames.get(s,[]): + for r in p.prod: + mark_reachable_from(r) + + reachable = { } + for s in list(self.Terminals) + list(self.Nonterminals): + reachable[s] = 0 + + mark_reachable_from( self.Productions[0].prod[0] ) + + return [s for s in list(self.Nonterminals) + if not reachable[s]] + + # ----------------------------------------------------------------------------- + # infinite_cycles() + # + # This function looks at the various parsing rules and tries to detect + # infinite recursion cycles (grammar rules where there is no possible way + # to derive a string of only terminals). + # ----------------------------------------------------------------------------- + + def infinite_cycles(self): + terminates = {} + + # Terminals: + for t in self.Terminals: + terminates[t] = 1 + + terminates['$end'] = 1 + + # Nonterminals: + + # Initialize to false: + for n in self.Nonterminals: + terminates[n] = 0 + + # Then propagate termination until no change: + while 1: + some_change = 0 + for (n,pl) in self.Prodnames.items(): + # Nonterminal n terminates iff any of its productions terminates. + for p in pl: + # Production p terminates iff all of its rhs symbols terminate. + for s in p.prod: + if not terminates[s]: + # The symbol s does not terminate, + # so production p does not terminate. + p_terminates = 0 + break + else: + # didn't break from the loop, + # so every symbol s terminates + # so production p terminates. + p_terminates = 1 + + if p_terminates: + # symbol n terminates! + if not terminates[n]: + terminates[n] = 1 + some_change = 1 + # Don't need to consider any more productions for this n. + break + + if not some_change: + break + + infinite = [] + for (s,term) in terminates.items(): + if not term: + if not s in self.Prodnames and not s in self.Terminals and s != 'error': + # s is used-but-not-defined, and we've already warned of that, + # so it would be overkill to say that it's also non-terminating. + pass + else: + infinite.append(s) + + return infinite + + + # ----------------------------------------------------------------------------- + # undefined_symbols() + # + # Find all symbols that were used the grammar, but not defined as tokens or + # grammar rules. Returns a list of tuples (sym, prod) where sym in the symbol + # and prod is the production where the symbol was used. + # ----------------------------------------------------------------------------- + def undefined_symbols(self): + result = [] + for p in self.Productions: + if not p: continue + + for s in p.prod: + if not s in self.Prodnames and not s in self.Terminals and s != 'error': + result.append((s,p)) + return result + + # ----------------------------------------------------------------------------- + # unused_terminals() + # + # Find all terminals that were defined, but not used by the grammar. Returns + # a list of all symbols. + # ----------------------------------------------------------------------------- + def unused_terminals(self): + unused_tok = [] + for s,v in self.Terminals.items(): + if s != 'error' and not v: + unused_tok.append(s) + + return unused_tok + + # ------------------------------------------------------------------------------ + # unused_rules() + # + # Find all grammar rules that were defined, but not used (maybe not reachable) + # Returns a list of productions. + # ------------------------------------------------------------------------------ + + def unused_rules(self): + unused_prod = [] + for s,v in self.Nonterminals.items(): + if not v: + p = self.Prodnames[s][0] + unused_prod.append(p) + return unused_prod + + # ----------------------------------------------------------------------------- + # unused_precedence() + # + # Returns a list of tuples (term,precedence) corresponding to precedence + # rules that were never used by the grammar. term is the name of the terminal + # on which precedence was applied and precedence is a string such as 'left' or + # 'right' corresponding to the type of precedence. + # ----------------------------------------------------------------------------- + + def unused_precedence(self): + unused = [] + for termname in self.Precedence: + if not (termname in self.Terminals or termname in self.UsedPrecedence): + unused.append((termname,self.Precedence[termname][0])) + + return unused + + # ------------------------------------------------------------------------- + # _first() + # + # Compute the value of FIRST1(beta) where beta is a tuple of symbols. + # + # During execution of compute_first1, the result may be incomplete. + # Afterward (e.g., when called from compute_follow()), it will be complete. + # ------------------------------------------------------------------------- + def _first(self,beta): + + # We are computing First(x1,x2,x3,...,xn) + result = [ ] + for x in beta: + x_produces_empty = 0 + + # Add all the non-<empty> symbols of First[x] to the result. + for f in self.First[x]: + if f == '<empty>': + x_produces_empty = 1 + else: + if f not in result: result.append(f) + + if x_produces_empty: + # We have to consider the next x in beta, + # i.e. stay in the loop. + pass + else: + # We don't have to consider any further symbols in beta. + break + else: + # There was no 'break' from the loop, + # so x_produces_empty was true for all x in beta, + # so beta produces empty as well. + result.append('<empty>') + + return result + + # ------------------------------------------------------------------------- + # compute_first() + # + # Compute the value of FIRST1(X) for all symbols + # ------------------------------------------------------------------------- + def compute_first(self): + if self.First: + return self.First + + # Terminals: + for t in self.Terminals: + self.First[t] = [t] + + self.First['$end'] = ['$end'] + + # Nonterminals: + + # Initialize to the empty set: + for n in self.Nonterminals: + self.First[n] = [] + + # Then propagate symbols until no change: + while 1: + some_change = 0 + for n in self.Nonterminals: + for p in self.Prodnames[n]: + for f in self._first(p.prod): + if f not in self.First[n]: + self.First[n].append( f ) + some_change = 1 + if not some_change: + break + + return self.First + + # --------------------------------------------------------------------- + # compute_follow() + # + # Computes all of the follow sets for every non-terminal symbol. The + # follow set is the set of all symbols that might follow a given + # non-terminal. See the Dragon book, 2nd Ed. p. 189. + # --------------------------------------------------------------------- + def compute_follow(self,start=None): + # If already computed, return the result + if self.Follow: + return self.Follow + + # If first sets not computed yet, do that first. + if not self.First: + self.compute_first() + + # Add '$end' to the follow list of the start symbol + for k in self.Nonterminals: + self.Follow[k] = [ ] + + if not start: + start = self.Productions[1].name + + self.Follow[start] = [ '$end' ] + + while 1: + didadd = 0 + for p in self.Productions[1:]: + # Here is the production set + for i in range(len(p.prod)): + B = p.prod[i] + if B in self.Nonterminals: + # Okay. We got a non-terminal in a production + fst = self._first(p.prod[i+1:]) + hasempty = 0 + for f in fst: + if f != '<empty>' and f not in self.Follow[B]: + self.Follow[B].append(f) + didadd = 1 + if f == '<empty>': + hasempty = 1 + if hasempty or i == (len(p.prod)-1): + # Add elements of follow(a) to follow(b) + for f in self.Follow[p.name]: + if f not in self.Follow[B]: + self.Follow[B].append(f) + didadd = 1 + if not didadd: break + return self.Follow + + + # ----------------------------------------------------------------------------- + # build_lritems() + # + # This function walks the list of productions and builds a complete set of the + # LR items. The LR items are stored in two ways: First, they are uniquely + # numbered and placed in the list _lritems. Second, a linked list of LR items + # is built for each production. For example: + # + # E -> E PLUS E + # + # Creates the list + # + # [E -> . E PLUS E, E -> E . PLUS E, E -> E PLUS . E, E -> E PLUS E . ] + # ----------------------------------------------------------------------------- + + def build_lritems(self): + for p in self.Productions: + lastlri = p + i = 0 + lr_items = [] + while 1: + if i > len(p): + lri = None + else: + lri = LRItem(p,i) + # Precompute the list of productions immediately following + try: + lri.lr_after = self.Prodnames[lri.prod[i+1]] + except (IndexError,KeyError): + lri.lr_after = [] + try: + lri.lr_before = lri.prod[i-1] + except IndexError: + lri.lr_before = None + + lastlri.lr_next = lri + if not lri: break + lr_items.append(lri) + lastlri = lri + i += 1 + p.lr_items = lr_items + +# ----------------------------------------------------------------------------- +# == Class LRTable == +# +# This basic class represents a basic table of LR parsing information. +# Methods for generating the tables are not defined here. They are defined +# in the derived class LRGeneratedTable. +# ----------------------------------------------------------------------------- + +class VersionError(YaccError): pass + +class LRTable(object): + def __init__(self): + self.lr_action = None + self.lr_goto = None + self.lr_productions = None + self.lr_method = None + + def read_table(self,module): + if isinstance(module,types.ModuleType): + parsetab = module + else: + if sys.version_info[0] < 3: + exec("import %s as parsetab" % module) + else: + env = { } + exec("import %s as parsetab" % module, env, env) + parsetab = env['parsetab'] + + if parsetab._tabversion != __tabversion__: + raise VersionError("yacc table file version is out of date") + + self.lr_action = parsetab._lr_action + self.lr_goto = parsetab._lr_goto + + self.lr_productions = [] + for p in parsetab._lr_productions: + self.lr_productions.append(MiniProduction(*p)) + + self.lr_method = parsetab._lr_method + return parsetab._lr_signature + + def read_pickle(self,filename): + try: + import cPickle as pickle + except ImportError: + import pickle + + in_f = open(filename,"rb") + + tabversion = pickle.load(in_f) + if tabversion != __tabversion__: + raise VersionError("yacc table file version is out of date") + self.lr_method = pickle.load(in_f) + signature = pickle.load(in_f) + self.lr_action = pickle.load(in_f) + self.lr_goto = pickle.load(in_f) + productions = pickle.load(in_f) + + self.lr_productions = [] + for p in productions: + self.lr_productions.append(MiniProduction(*p)) + + in_f.close() + return signature + + # Bind all production function names to callable objects in pdict + def bind_callables(self,pdict): + for p in self.lr_productions: + p.bind(pdict) + +# ----------------------------------------------------------------------------- +# === LR Generator === +# +# The following classes and functions are used to generate LR parsing tables on +# a grammar. +# ----------------------------------------------------------------------------- + +# ----------------------------------------------------------------------------- +# digraph() +# traverse() +# +# The following two functions are used to compute set valued functions +# of the form: +# +# F(x) = F'(x) U U{F(y) | x R y} +# +# This is used to compute the values of Read() sets as well as FOLLOW sets +# in LALR(1) generation. +# +# Inputs: X - An input set +# R - A relation +# FP - Set-valued function +# ------------------------------------------------------------------------------ + +def digraph(X,R,FP): + N = { } + for x in X: + N[x] = 0 + stack = [] + F = { } + for x in X: + if N[x] == 0: traverse(x,N,stack,F,X,R,FP) + return F + +def traverse(x,N,stack,F,X,R,FP): + stack.append(x) + d = len(stack) + N[x] = d + F[x] = FP(x) # F(X) <- F'(x) + + rel = R(x) # Get y's related to x + for y in rel: + if N[y] == 0: + traverse(y,N,stack,F,X,R,FP) + N[x] = min(N[x],N[y]) + for a in F.get(y,[]): + if a not in F[x]: F[x].append(a) + if N[x] == d: + N[stack[-1]] = MAXINT + F[stack[-1]] = F[x] + element = stack.pop() + while element != x: + N[stack[-1]] = MAXINT + F[stack[-1]] = F[x] + element = stack.pop() + +class LALRError(YaccError): pass + +# ----------------------------------------------------------------------------- +# == LRGeneratedTable == +# +# This class implements the LR table generation algorithm. There are no +# public methods except for write() +# ----------------------------------------------------------------------------- + +class LRGeneratedTable(LRTable): + def __init__(self,grammar,method='LALR',log=None): + if method not in ['SLR','LALR']: + raise LALRError("Unsupported method %s" % method) + + self.grammar = grammar + self.lr_method = method + + # Set up the logger + if not log: + log = NullLogger() + self.log = log + + # Internal attributes + self.lr_action = {} # Action table + self.lr_goto = {} # Goto table + self.lr_productions = grammar.Productions # Copy of grammar Production array + self.lr_goto_cache = {} # Cache of computed gotos + self.lr0_cidhash = {} # Cache of closures + + self._add_count = 0 # Internal counter used to detect cycles + + # Diagonistic information filled in by the table generator + self.sr_conflict = 0 + self.rr_conflict = 0 + self.conflicts = [] # List of conflicts + + self.sr_conflicts = [] + self.rr_conflicts = [] + + # Build the tables + self.grammar.build_lritems() + self.grammar.compute_first() + self.grammar.compute_follow() + self.lr_parse_table() + + # Compute the LR(0) closure operation on I, where I is a set of LR(0) items. + + def lr0_closure(self,I): + self._add_count += 1 + + # Add everything in I to J + J = I[:] + didadd = 1 + while didadd: + didadd = 0 + for j in J: + for x in j.lr_after: + if getattr(x,"lr0_added",0) == self._add_count: continue + # Add B --> .G to J + J.append(x.lr_next) + x.lr0_added = self._add_count + didadd = 1 + + return J + + # Compute the LR(0) goto function goto(I,X) where I is a set + # of LR(0) items and X is a grammar symbol. This function is written + # in a way that guarantees uniqueness of the generated goto sets + # (i.e. the same goto set will never be returned as two different Python + # objects). With uniqueness, we can later do fast set comparisons using + # id(obj) instead of element-wise comparison. + + def lr0_goto(self,I,x): + # First we look for a previously cached entry + g = self.lr_goto_cache.get((id(I),x),None) + if g: return g + + # Now we generate the goto set in a way that guarantees uniqueness + # of the result + + s = self.lr_goto_cache.get(x,None) + if not s: + s = { } + self.lr_goto_cache[x] = s + + gs = [ ] + for p in I: + n = p.lr_next + if n and n.lr_before == x: + s1 = s.get(id(n),None) + if not s1: + s1 = { } + s[id(n)] = s1 + gs.append(n) + s = s1 + g = s.get('$end',None) + if not g: + if gs: + g = self.lr0_closure(gs) + s['$end'] = g + else: + s['$end'] = gs + self.lr_goto_cache[(id(I),x)] = g + return g + + # Compute the LR(0) sets of item function + def lr0_items(self): + + C = [ self.lr0_closure([self.grammar.Productions[0].lr_next]) ] + i = 0 + for I in C: + self.lr0_cidhash[id(I)] = i + i += 1 + + # Loop over the items in C and each grammar symbols + i = 0 + while i < len(C): + I = C[i] + i += 1 + + # Collect all of the symbols that could possibly be in the goto(I,X) sets + asyms = { } + for ii in I: + for s in ii.usyms: + asyms[s] = None + + for x in asyms: + g = self.lr0_goto(I,x) + if not g: continue + if id(g) in self.lr0_cidhash: continue + self.lr0_cidhash[id(g)] = len(C) + C.append(g) + + return C + + # ----------------------------------------------------------------------------- + # ==== LALR(1) Parsing ==== + # + # LALR(1) parsing is almost exactly the same as SLR except that instead of + # relying upon Follow() sets when performing reductions, a more selective + # lookahead set that incorporates the state of the LR(0) machine is utilized. + # Thus, we mainly just have to focus on calculating the lookahead sets. + # + # The method used here is due to DeRemer and Pennelo (1982). + # + # DeRemer, F. L., and T. J. Pennelo: "Efficient Computation of LALR(1) + # Lookahead Sets", ACM Transactions on Programming Languages and Systems, + # Vol. 4, No. 4, Oct. 1982, pp. 615-649 + # + # Further details can also be found in: + # + # J. Tremblay and P. Sorenson, "The Theory and Practice of Compiler Writing", + # McGraw-Hill Book Company, (1985). + # + # ----------------------------------------------------------------------------- + + # ----------------------------------------------------------------------------- + # compute_nullable_nonterminals() + # + # Creates a dictionary containing all of the non-terminals that might produce + # an empty production. + # ----------------------------------------------------------------------------- + + def compute_nullable_nonterminals(self): + nullable = {} + num_nullable = 0 + while 1: + for p in self.grammar.Productions[1:]: + if p.len == 0: + nullable[p.name] = 1 + continue + for t in p.prod: + if not t in nullable: break + else: + nullable[p.name] = 1 + if len(nullable) == num_nullable: break + num_nullable = len(nullable) + return nullable + + # ----------------------------------------------------------------------------- + # find_nonterminal_trans(C) + # + # Given a set of LR(0) items, this functions finds all of the non-terminal + # transitions. These are transitions in which a dot appears immediately before + # a non-terminal. Returns a list of tuples of the form (state,N) where state + # is the state number and N is the nonterminal symbol. + # + # The input C is the set of LR(0) items. + # ----------------------------------------------------------------------------- + + def find_nonterminal_transitions(self,C): + trans = [] + for state in range(len(C)): + for p in C[state]: + if p.lr_index < p.len - 1: + t = (state,p.prod[p.lr_index+1]) + if t[1] in self.grammar.Nonterminals: + if t not in trans: trans.append(t) + state = state + 1 + return trans + + # ----------------------------------------------------------------------------- + # dr_relation() + # + # Computes the DR(p,A) relationships for non-terminal transitions. The input + # is a tuple (state,N) where state is a number and N is a nonterminal symbol. + # + # Returns a list of terminals. + # ----------------------------------------------------------------------------- + + def dr_relation(self,C,trans,nullable): + dr_set = { } + state,N = trans + terms = [] + + g = self.lr0_goto(C[state],N) + for p in g: + if p.lr_index < p.len - 1: + a = p.prod[p.lr_index+1] + if a in self.grammar.Terminals: + if a not in terms: terms.append(a) + + # This extra bit is to handle the start state + if state == 0 and N == self.grammar.Productions[0].prod[0]: + terms.append('$end') + + return terms + + # ----------------------------------------------------------------------------- + # reads_relation() + # + # Computes the READS() relation (p,A) READS (t,C). + # ----------------------------------------------------------------------------- + + def reads_relation(self,C, trans, empty): + # Look for empty transitions + rel = [] + state, N = trans + + g = self.lr0_goto(C[state],N) + j = self.lr0_cidhash.get(id(g),-1) + for p in g: + if p.lr_index < p.len - 1: + a = p.prod[p.lr_index + 1] + if a in empty: + rel.append((j,a)) + + return rel + + # ----------------------------------------------------------------------------- + # compute_lookback_includes() + # + # Determines the lookback and includes relations + # + # LOOKBACK: + # + # This relation is determined by running the LR(0) state machine forward. + # For example, starting with a production "N : . A B C", we run it forward + # to obtain "N : A B C ." We then build a relationship between this final + # state and the starting state. These relationships are stored in a dictionary + # lookdict. + # + # INCLUDES: + # + # Computes the INCLUDE() relation (p,A) INCLUDES (p',B). + # + # This relation is used to determine non-terminal transitions that occur + # inside of other non-terminal transition states. (p,A) INCLUDES (p', B) + # if the following holds: + # + # B -> LAT, where T -> epsilon and p' -L-> p + # + # L is essentially a prefix (which may be empty), T is a suffix that must be + # able to derive an empty string. State p' must lead to state p with the string L. + # + # ----------------------------------------------------------------------------- + + def compute_lookback_includes(self,C,trans,nullable): + + lookdict = {} # Dictionary of lookback relations + includedict = {} # Dictionary of include relations + + # Make a dictionary of non-terminal transitions + dtrans = {} + for t in trans: + dtrans[t] = 1 + + # Loop over all transitions and compute lookbacks and includes + for state,N in trans: + lookb = [] + includes = [] + for p in C[state]: + if p.name != N: continue + + # Okay, we have a name match. We now follow the production all the way + # through the state machine until we get the . on the right hand side + + lr_index = p.lr_index + j = state + while lr_index < p.len - 1: + lr_index = lr_index + 1 + t = p.prod[lr_index] + + # Check to see if this symbol and state are a non-terminal transition + if (j,t) in dtrans: + # Yes. Okay, there is some chance that this is an includes relation + # the only way to know for certain is whether the rest of the + # production derives empty + + li = lr_index + 1 + while li < p.len: + if p.prod[li] in self.grammar.Terminals: break # No forget it + if not p.prod[li] in nullable: break + li = li + 1 + else: + # Appears to be a relation between (j,t) and (state,N) + includes.append((j,t)) + + g = self.lr0_goto(C[j],t) # Go to next set + j = self.lr0_cidhash.get(id(g),-1) # Go to next state + + # When we get here, j is the final state, now we have to locate the production + for r in C[j]: + if r.name != p.name: continue + if r.len != p.len: continue + i = 0 + # This look is comparing a production ". A B C" with "A B C ." + while i < r.lr_index: + if r.prod[i] != p.prod[i+1]: break + i = i + 1 + else: + lookb.append((j,r)) + for i in includes: + if not i in includedict: includedict[i] = [] + includedict[i].append((state,N)) + lookdict[(state,N)] = lookb + + return lookdict,includedict + + # ----------------------------------------------------------------------------- + # compute_read_sets() + # + # Given a set of LR(0) items, this function computes the read sets. + # + # Inputs: C = Set of LR(0) items + # ntrans = Set of nonterminal transitions + # nullable = Set of empty transitions + # + # Returns a set containing the read sets + # ----------------------------------------------------------------------------- + + def compute_read_sets(self,C, ntrans, nullable): + FP = lambda x: self.dr_relation(C,x,nullable) + R = lambda x: self.reads_relation(C,x,nullable) + F = digraph(ntrans,R,FP) + return F + + # ----------------------------------------------------------------------------- + # compute_follow_sets() + # + # Given a set of LR(0) items, a set of non-terminal transitions, a readset, + # and an include set, this function computes the follow sets + # + # Follow(p,A) = Read(p,A) U U {Follow(p',B) | (p,A) INCLUDES (p',B)} + # + # Inputs: + # ntrans = Set of nonterminal transitions + # readsets = Readset (previously computed) + # inclsets = Include sets (previously computed) + # + # Returns a set containing the follow sets + # ----------------------------------------------------------------------------- + + def compute_follow_sets(self,ntrans,readsets,inclsets): + FP = lambda x: readsets[x] + R = lambda x: inclsets.get(x,[]) + F = digraph(ntrans,R,FP) + return F + + # ----------------------------------------------------------------------------- + # add_lookaheads() + # + # Attaches the lookahead symbols to grammar rules. + # + # Inputs: lookbacks - Set of lookback relations + # followset - Computed follow set + # + # This function directly attaches the lookaheads to productions contained + # in the lookbacks set + # ----------------------------------------------------------------------------- + + def add_lookaheads(self,lookbacks,followset): + for trans,lb in lookbacks.items(): + # Loop over productions in lookback + for state,p in lb: + if not state in p.lookaheads: + p.lookaheads[state] = [] + f = followset.get(trans,[]) + for a in f: + if a not in p.lookaheads[state]: p.lookaheads[state].append(a) + + # ----------------------------------------------------------------------------- + # add_lalr_lookaheads() + # + # This function does all of the work of adding lookahead information for use + # with LALR parsing + # ----------------------------------------------------------------------------- + + def add_lalr_lookaheads(self,C): + # Determine all of the nullable nonterminals + nullable = self.compute_nullable_nonterminals() + + # Find all non-terminal transitions + trans = self.find_nonterminal_transitions(C) + + # Compute read sets + readsets = self.compute_read_sets(C,trans,nullable) + + # Compute lookback/includes relations + lookd, included = self.compute_lookback_includes(C,trans,nullable) + + # Compute LALR FOLLOW sets + followsets = self.compute_follow_sets(trans,readsets,included) + + # Add all of the lookaheads + self.add_lookaheads(lookd,followsets) + + # ----------------------------------------------------------------------------- + # lr_parse_table() + # + # This function constructs the parse tables for SLR or LALR + # ----------------------------------------------------------------------------- + def lr_parse_table(self): + Productions = self.grammar.Productions + Precedence = self.grammar.Precedence + goto = self.lr_goto # Goto array + action = self.lr_action # Action array + log = self.log # Logger for output + + actionp = { } # Action production array (temporary) + + log.info("Parsing method: %s", self.lr_method) + + # Step 1: Construct C = { I0, I1, ... IN}, collection of LR(0) items + # This determines the number of states + + C = self.lr0_items() + + if self.lr_method == 'LALR': + self.add_lalr_lookaheads(C) + + # Build the parser table, state by state + st = 0 + for I in C: + # Loop over each production in I + actlist = [ ] # List of actions + st_action = { } + st_actionp = { } + st_goto = { } + log.info("") + log.info("state %d", st) + log.info("") + for p in I: + log.info(" (%d) %s", p.number, str(p)) + log.info("") + + for p in I: + if p.len == p.lr_index + 1: + if p.name == "S'": + # Start symbol. Accept! + st_action["$end"] = 0 + st_actionp["$end"] = p + else: + # We are at the end of a production. Reduce! + if self.lr_method == 'LALR': + laheads = p.lookaheads[st] + else: + laheads = self.grammar.Follow[p.name] + for a in laheads: + actlist.append((a,p,"reduce using rule %d (%s)" % (p.number,p))) + r = st_action.get(a,None) + if r is not None: + # Whoa. Have a shift/reduce or reduce/reduce conflict + if r > 0: + # Need to decide on shift or reduce here + # By default we favor shifting. Need to add + # some precedence rules here. + sprec,slevel = Productions[st_actionp[a].number].prec + rprec,rlevel = Precedence.get(a,('right',0)) + if (slevel < rlevel) or ((slevel == rlevel) and (rprec == 'left')): + # We really need to reduce here. + st_action[a] = -p.number + st_actionp[a] = p + if not slevel and not rlevel: + log.info(" ! shift/reduce conflict for %s resolved as reduce",a) + self.sr_conflicts.append((st,a,'reduce')) + Productions[p.number].reduced += 1 + elif (slevel == rlevel) and (rprec == 'nonassoc'): + st_action[a] = None + else: + # Hmmm. Guess we'll keep the shift + if not rlevel: + log.info(" ! shift/reduce conflict for %s resolved as shift",a) + self.sr_conflicts.append((st,a,'shift')) + elif r < 0: + # Reduce/reduce conflict. In this case, we favor the rule + # that was defined first in the grammar file + oldp = Productions[-r] + pp = Productions[p.number] + if oldp.line > pp.line: + st_action[a] = -p.number + st_actionp[a] = p + chosenp,rejectp = pp,oldp + Productions[p.number].reduced += 1 + Productions[oldp.number].reduced -= 1 + else: + chosenp,rejectp = oldp,pp + self.rr_conflicts.append((st,chosenp,rejectp)) + log.info(" ! reduce/reduce conflict for %s resolved using rule %d (%s)", a,st_actionp[a].number, st_actionp[a]) + else: + raise LALRError("Unknown conflict in state %d" % st) + else: + st_action[a] = -p.number + st_actionp[a] = p + Productions[p.number].reduced += 1 + else: + i = p.lr_index + a = p.prod[i+1] # Get symbol right after the "." + if a in self.grammar.Terminals: + g = self.lr0_goto(I,a) + j = self.lr0_cidhash.get(id(g),-1) + if j >= 0: + # We are in a shift state + actlist.append((a,p,"shift and go to state %d" % j)) + r = st_action.get(a,None) + if r is not None: + # Whoa have a shift/reduce or shift/shift conflict + if r > 0: + if r != j: + raise LALRError("Shift/shift conflict in state %d" % st) + elif r < 0: + # Do a precedence check. + # - if precedence of reduce rule is higher, we reduce. + # - if precedence of reduce is same and left assoc, we reduce. + # - otherwise we shift + rprec,rlevel = Productions[st_actionp[a].number].prec + sprec,slevel = Precedence.get(a,('right',0)) + if (slevel > rlevel) or ((slevel == rlevel) and (rprec == 'right')): + # We decide to shift here... highest precedence to shift + Productions[st_actionp[a].number].reduced -= 1 + st_action[a] = j + st_actionp[a] = p + if not rlevel: + log.info(" ! shift/reduce conflict for %s resolved as shift",a) + self.sr_conflicts.append((st,a,'shift')) + elif (slevel == rlevel) and (rprec == 'nonassoc'): + st_action[a] = None + else: + # Hmmm. Guess we'll keep the reduce + if not slevel and not rlevel: + log.info(" ! shift/reduce conflict for %s resolved as reduce",a) + self.sr_conflicts.append((st,a,'reduce')) + + else: + raise LALRError("Unknown conflict in state %d" % st) + else: + st_action[a] = j + st_actionp[a] = p + + # Print the actions associated with each terminal + _actprint = { } + for a,p,m in actlist: + if a in st_action: + if p is st_actionp[a]: + log.info(" %-15s %s",a,m) + _actprint[(a,m)] = 1 + log.info("") + # Print the actions that were not used. (debugging) + not_used = 0 + for a,p,m in actlist: + if a in st_action: + if p is not st_actionp[a]: + if not (a,m) in _actprint: + log.debug(" ! %-15s [ %s ]",a,m) + not_used = 1 + _actprint[(a,m)] = 1 + if not_used: + log.debug("") + + # Construct the goto table for this state + + nkeys = { } + for ii in I: + for s in ii.usyms: + if s in self.grammar.Nonterminals: + nkeys[s] = None + for n in nkeys: + g = self.lr0_goto(I,n) + j = self.lr0_cidhash.get(id(g),-1) + if j >= 0: + st_goto[n] = j + log.info(" %-30s shift and go to state %d",n,j) + + action[st] = st_action + actionp[st] = st_actionp + goto[st] = st_goto + st += 1 + + + # ----------------------------------------------------------------------------- + # write() + # + # This function writes the LR parsing tables to a file + # ----------------------------------------------------------------------------- + + def write_table(self,modulename,outputdir='',signature=""): + basemodulename = modulename.split(".")[-1] + filename = os.path.join(outputdir,basemodulename) + ".py" + try: + f = open(filename,"w") + + f.write(""" +# %s +# This file is automatically generated. Do not edit. +_tabversion = %r + +_lr_method = %r + +_lr_signature = %r + """ % (filename, __tabversion__, self.lr_method, signature)) + + # Change smaller to 0 to go back to original tables + smaller = 1 + + # Factor out names to try and make smaller + if smaller: + items = { } + + for s,nd in self.lr_action.items(): + for name,v in nd.items(): + i = items.get(name) + if not i: + i = ([],[]) + items[name] = i + i[0].append(s) + i[1].append(v) + + f.write("\n_lr_action_items = {") + for k,v in items.items(): + f.write("%r:([" % k) + for i in v[0]: + f.write("%r," % i) + f.write("],[") + for i in v[1]: + f.write("%r," % i) + + f.write("]),") + f.write("}\n") + + f.write(""" +_lr_action = { } +for _k, _v in _lr_action_items.items(): + for _x,_y in zip(_v[0],_v[1]): + if not _x in _lr_action: _lr_action[_x] = { } + _lr_action[_x][_k] = _y +del _lr_action_items +""") + + else: + f.write("\n_lr_action = { "); + for k,v in self.lr_action.items(): + f.write("(%r,%r):%r," % (k[0],k[1],v)) + f.write("}\n"); + + if smaller: + # Factor out names to try and make smaller + items = { } + + for s,nd in self.lr_goto.items(): + for name,v in nd.items(): + i = items.get(name) + if not i: + i = ([],[]) + items[name] = i + i[0].append(s) + i[1].append(v) + + f.write("\n_lr_goto_items = {") + for k,v in items.items(): + f.write("%r:([" % k) + for i in v[0]: + f.write("%r," % i) + f.write("],[") + for i in v[1]: + f.write("%r," % i) + + f.write("]),") + f.write("}\n") + + f.write(""" +_lr_goto = { } +for _k, _v in _lr_goto_items.items(): + for _x,_y in zip(_v[0],_v[1]): + if not _x in _lr_goto: _lr_goto[_x] = { } + _lr_goto[_x][_k] = _y +del _lr_goto_items +""") + else: + f.write("\n_lr_goto = { "); + for k,v in self.lr_goto.items(): + f.write("(%r,%r):%r," % (k[0],k[1],v)) + f.write("}\n"); + + # Write production table + f.write("_lr_productions = [\n") + for p in self.lr_productions: + if p.func: + f.write(" (%r,%r,%d,%r,%r,%d),\n" % (p.str,p.name, p.len, p.func,p.file,p.line)) + else: + f.write(" (%r,%r,%d,None,None,None),\n" % (str(p),p.name, p.len)) + f.write("]\n") + f.close() + + except IOError: + e = sys.exc_info()[1] + sys.stderr.write("Unable to create '%s'\n" % filename) + sys.stderr.write(str(e)+"\n") + return + + + # ----------------------------------------------------------------------------- + # pickle_table() + # + # This function pickles the LR parsing tables to a supplied file object + # ----------------------------------------------------------------------------- + + def pickle_table(self,filename,signature=""): + try: + import cPickle as pickle + except ImportError: + import pickle + outf = open(filename,"wb") + pickle.dump(__tabversion__,outf,pickle_protocol) + pickle.dump(self.lr_method,outf,pickle_protocol) + pickle.dump(signature,outf,pickle_protocol) + pickle.dump(self.lr_action,outf,pickle_protocol) + pickle.dump(self.lr_goto,outf,pickle_protocol) + + outp = [] + for p in self.lr_productions: + if p.func: + outp.append((p.str,p.name, p.len, p.func,p.file,p.line)) + else: + outp.append((str(p),p.name,p.len,None,None,None)) + pickle.dump(outp,outf,pickle_protocol) + outf.close() + +# ----------------------------------------------------------------------------- +# === INTROSPECTION === +# +# The following functions and classes are used to implement the PLY +# introspection features followed by the yacc() function itself. +# ----------------------------------------------------------------------------- + +# ----------------------------------------------------------------------------- +# get_caller_module_dict() +# +# This function returns a dictionary containing all of the symbols defined within +# a caller further down the call stack. This is used to get the environment +# associated with the yacc() call if none was provided. +# ----------------------------------------------------------------------------- + +def get_caller_module_dict(levels): + try: + raise RuntimeError + except RuntimeError: + e,b,t = sys.exc_info() + f = t.tb_frame + while levels > 0: + f = f.f_back + levels -= 1 + ldict = f.f_globals.copy() + if f.f_globals != f.f_locals: + ldict.update(f.f_locals) + + return ldict + +# ----------------------------------------------------------------------------- +# parse_grammar() +# +# This takes a raw grammar rule string and parses it into production data +# ----------------------------------------------------------------------------- +def parse_grammar(doc,file,line): + grammar = [] + # Split the doc string into lines + pstrings = doc.splitlines() + lastp = None + dline = line + for ps in pstrings: + dline += 1 + p = ps.split() + if not p: continue + try: + if p[0] == '|': + # This is a continuation of a previous rule + if not lastp: + raise SyntaxError("%s:%d: Misplaced '|'" % (file,dline)) + prodname = lastp + syms = p[1:] + else: + prodname = p[0] + lastp = prodname + syms = p[2:] + assign = p[1] + if assign != ':' and assign != '::=': + raise SyntaxError("%s:%d: Syntax error. Expected ':'" % (file,dline)) + + grammar.append((file,dline,prodname,syms)) + except SyntaxError: + raise + except Exception: + raise SyntaxError("%s:%d: Syntax error in rule '%s'" % (file,dline,ps.strip())) + + return grammar + +# ----------------------------------------------------------------------------- +# ParserReflect() +# +# This class represents information extracted for building a parser including +# start symbol, error function, tokens, precedence list, action functions, +# etc. +# ----------------------------------------------------------------------------- +class ParserReflect(object): + def __init__(self,pdict,log=None): + self.pdict = pdict + self.start = None + self.error_func = None + self.tokens = None + self.files = {} + self.grammar = [] + self.error = 0 + + if log is None: + self.log = PlyLogger(sys.stderr) + else: + self.log = log + + # Get all of the basic information + def get_all(self): + self.get_start() + self.get_error_func() + self.get_tokens() + self.get_precedence() + self.get_pfunctions() + + # Validate all of the information + def validate_all(self): + self.validate_start() + self.validate_error_func() + self.validate_tokens() + self.validate_precedence() + self.validate_pfunctions() + self.validate_files() + return self.error + + # Compute a signature over the grammar + def signature(self): + try: + from hashlib import md5 + except ImportError: + from md5 import md5 + try: + sig = md5() + if self.start: + sig.update(self.start.encode('latin-1')) + if self.prec: + sig.update("".join(["".join(p) for p in self.prec]).encode('latin-1')) + if self.tokens: + sig.update(" ".join(self.tokens).encode('latin-1')) + for f in self.pfuncs: + if f[3]: + sig.update(f[3].encode('latin-1')) + except (TypeError,ValueError): + pass + return sig.digest() + + # ----------------------------------------------------------------------------- + # validate_file() + # + # This method checks to see if there are duplicated p_rulename() functions + # in the parser module file. Without this function, it is really easy for + # users to make mistakes by cutting and pasting code fragments (and it's a real + # bugger to try and figure out why the resulting parser doesn't work). Therefore, + # we just do a little regular expression pattern matching of def statements + # to try and detect duplicates. + # ----------------------------------------------------------------------------- + + def validate_files(self): + # Match def p_funcname( + fre = re.compile(r'\s*def\s+(p_[a-zA-Z_0-9]*)\(') + + for filename in self.files.keys(): + base,ext = os.path.splitext(filename) + if ext != '.py': return 1 # No idea. Assume it's okay. + + try: + f = open(filename) + lines = f.readlines() + f.close() + except IOError: + continue + + counthash = { } + for linen,l in enumerate(lines): + linen += 1 + m = fre.match(l) + if m: + name = m.group(1) + prev = counthash.get(name) + if not prev: + counthash[name] = linen + else: + self.log.warning("%s:%d: Function %s redefined. Previously defined on line %d", filename,linen,name,prev) + + # Get the start symbol + def get_start(self): + self.start = self.pdict.get('start') + + # Validate the start symbol + def validate_start(self): + if self.start is not None: + if not isinstance(self.start,str): + self.log.error("'start' must be a string") + + # Look for error handler + def get_error_func(self): + self.error_func = self.pdict.get('p_error') + + # Validate the error function + def validate_error_func(self): + if self.error_func: + if isinstance(self.error_func,types.FunctionType): + ismethod = 0 + elif isinstance(self.error_func, types.MethodType): + ismethod = 1 + else: + self.log.error("'p_error' defined, but is not a function or method") + self.error = 1 + return + + eline = func_code(self.error_func).co_firstlineno + efile = func_code(self.error_func).co_filename + self.files[efile] = 1 + + if (func_code(self.error_func).co_argcount != 1+ismethod): + self.log.error("%s:%d: p_error() requires 1 argument",efile,eline) + self.error = 1 + + # Get the tokens map + def get_tokens(self): + tokens = self.pdict.get("tokens",None) + if not tokens: + self.log.error("No token list is defined") + self.error = 1 + return + + if not isinstance(tokens,(list, tuple)): + self.log.error("tokens must be a list or tuple") + self.error = 1 + return + + if not tokens: + self.log.error("tokens is empty") + self.error = 1 + return + + self.tokens = tokens + + # Validate the tokens + def validate_tokens(self): + # Validate the tokens. + if 'error' in self.tokens: + self.log.error("Illegal token name 'error'. Is a reserved word") + self.error = 1 + return + + terminals = {} + for n in self.tokens: + if n in terminals: + self.log.warning("Token '%s' multiply defined", n) + terminals[n] = 1 + + # Get the precedence map (if any) + def get_precedence(self): + self.prec = self.pdict.get("precedence",None) + + # Validate and parse the precedence map + def validate_precedence(self): + preclist = [] + if self.prec: + if not isinstance(self.prec,(list,tuple)): + self.log.error("precedence must be a list or tuple") + self.error = 1 + return + for level,p in enumerate(self.prec): + if not isinstance(p,(list,tuple)): + self.log.error("Bad precedence table") + self.error = 1 + return + + if len(p) < 2: + self.log.error("Malformed precedence entry %s. Must be (assoc, term, ..., term)",p) + self.error = 1 + return + assoc = p[0] + if not isinstance(assoc,str): + self.log.error("precedence associativity must be a string") + self.error = 1 + return + for term in p[1:]: + if not isinstance(term,str): + self.log.error("precedence items must be strings") + self.error = 1 + return + preclist.append((term,assoc,level+1)) + self.preclist = preclist + + # Get all p_functions from the grammar + def get_pfunctions(self): + p_functions = [] + for name, item in self.pdict.items(): + if name[:2] != 'p_': continue + if name == 'p_error': continue + if isinstance(item,(types.FunctionType,types.MethodType)): + line = func_code(item).co_firstlineno + file = func_code(item).co_filename + p_functions.append((line,file,name,item.__doc__)) + + # Sort all of the actions by line number + p_functions.sort() + self.pfuncs = p_functions + + + # Validate all of the p_functions + def validate_pfunctions(self): + grammar = [] + # Check for non-empty symbols + if len(self.pfuncs) == 0: + self.log.error("no rules of the form p_rulename are defined") + self.error = 1 + return + + for line, file, name, doc in self.pfuncs: + func = self.pdict[name] + if isinstance(func, types.MethodType): + reqargs = 2 + else: + reqargs = 1 + if func_code(func).co_argcount > reqargs: + self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,func.__name__) + self.error = 1 + elif func_code(func).co_argcount < reqargs: + self.log.error("%s:%d: Rule '%s' requires an argument",file,line,func.__name__) + self.error = 1 + elif not func.__doc__: + self.log.warning("%s:%d: No documentation string specified in function '%s' (ignored)",file,line,func.__name__) + else: + try: + parsed_g = parse_grammar(doc,file,line) + for g in parsed_g: + grammar.append((name, g)) + except SyntaxError: + e = sys.exc_info()[1] + self.log.error(str(e)) + self.error = 1 + + # Looks like a valid grammar rule + # Mark the file in which defined. + self.files[file] = 1 + + # Secondary validation step that looks for p_ definitions that are not functions + # or functions that look like they might be grammar rules. + + for n,v in self.pdict.items(): + if n[0:2] == 'p_' and isinstance(v, (types.FunctionType, types.MethodType)): continue + if n[0:2] == 't_': continue + if n[0:2] == 'p_' and n != 'p_error': + self.log.warning("'%s' not defined as a function", n) + if ((isinstance(v,types.FunctionType) and func_code(v).co_argcount == 1) or + (isinstance(v,types.MethodType) and func_code(v).co_argcount == 2)): + try: + doc = v.__doc__.split(" ") + if doc[1] == ':': + self.log.warning("%s:%d: Possible grammar rule '%s' defined without p_ prefix", + func_code(v).co_filename, func_code(v).co_firstlineno,n) + except Exception: + pass + + self.grammar = grammar + +# ----------------------------------------------------------------------------- +# yacc(module) +# +# Build a parser +# ----------------------------------------------------------------------------- + +def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, start=None, + check_recursion=1, optimize=0, write_tables=1, debugfile=debug_file,outputdir='', + debuglog=None, errorlog = None, picklefile=None): + + global parse # Reference to the parsing method of the last built parser + + # If pickling is enabled, table files are not created + + if picklefile: + write_tables = 0 + + if errorlog is None: + errorlog = PlyLogger(sys.stderr) + + # Get the module dictionary used for the parser + if module: + _items = [(k,getattr(module,k)) for k in dir(module)] + pdict = dict(_items) + else: + pdict = get_caller_module_dict(2) + + # Collect parser information from the dictionary + pinfo = ParserReflect(pdict,log=errorlog) + pinfo.get_all() + + if pinfo.error: + raise YaccError("Unable to build parser") + + # Check signature against table files (if any) + signature = pinfo.signature() + + # Read the tables + try: + lr = LRTable() + if picklefile: + read_signature = lr.read_pickle(picklefile) + else: + read_signature = lr.read_table(tabmodule) + if optimize or (read_signature == signature): + try: + lr.bind_callables(pinfo.pdict) + parser = LRParser(lr,pinfo.error_func) + parse = parser.parse + return parser + except Exception: + e = sys.exc_info()[1] + errorlog.warning("There was a problem loading the table file: %s", repr(e)) + except VersionError: + e = sys.exc_info() + errorlog.warning(str(e)) + except Exception: + pass + + if debuglog is None: + if debug: + debuglog = PlyLogger(open(debugfile,"w")) + else: + debuglog = NullLogger() + + debuglog.info("Created by PLY version %s (http://www.dabeaz.com/ply)", __version__) + + + errors = 0 + + # Validate the parser information + if pinfo.validate_all(): + raise YaccError("Unable to build parser") + + if not pinfo.error_func: + errorlog.warning("no p_error() function is defined") + + # Create a grammar object + grammar = Grammar(pinfo.tokens) + + # Set precedence level for terminals + for term, assoc, level in pinfo.preclist: + try: + grammar.set_precedence(term,assoc,level) + except GrammarError: + e = sys.exc_info()[1] + errorlog.warning("%s",str(e)) + + # Add productions to the grammar + for funcname, gram in pinfo.grammar: + file, line, prodname, syms = gram + try: + grammar.add_production(prodname,syms,funcname,file,line) + except GrammarError: + e = sys.exc_info()[1] + errorlog.error("%s",str(e)) + errors = 1 + + # Set the grammar start symbols + try: + if start is None: + grammar.set_start(pinfo.start) + else: + grammar.set_start(start) + except GrammarError: + e = sys.exc_info()[1] + errorlog.error(str(e)) + errors = 1 + + if errors: + raise YaccError("Unable to build parser") + + # Verify the grammar structure + undefined_symbols = grammar.undefined_symbols() + for sym, prod in undefined_symbols: + errorlog.error("%s:%d: Symbol '%s' used, but not defined as a token or a rule",prod.file,prod.line,sym) + errors = 1 + + unused_terminals = grammar.unused_terminals() + if unused_terminals: + debuglog.info("") + debuglog.info("Unused terminals:") + debuglog.info("") + for term in unused_terminals: + errorlog.warning("Token '%s' defined, but not used", term) + debuglog.info(" %s", term) + + # Print out all productions to the debug log + if debug: + debuglog.info("") + debuglog.info("Grammar") + debuglog.info("") + for n,p in enumerate(grammar.Productions): + debuglog.info("Rule %-5d %s", n, p) + + # Find unused non-terminals + unused_rules = grammar.unused_rules() + for prod in unused_rules: + errorlog.warning("%s:%d: Rule '%s' defined, but not used", prod.file, prod.line, prod.name) + + if len(unused_terminals) == 1: + errorlog.warning("There is 1 unused token") + if len(unused_terminals) > 1: + errorlog.warning("There are %d unused tokens", len(unused_terminals)) + + if len(unused_rules) == 1: + errorlog.warning("There is 1 unused rule") + if len(unused_rules) > 1: + errorlog.warning("There are %d unused rules", len(unused_rules)) + + if debug: + debuglog.info("") + debuglog.info("Terminals, with rules where they appear") + debuglog.info("") + terms = list(grammar.Terminals) + terms.sort() + for term in terms: + debuglog.info("%-20s : %s", term, " ".join([str(s) for s in grammar.Terminals[term]])) + + debuglog.info("") + debuglog.info("Nonterminals, with rules where they appear") + debuglog.info("") + nonterms = list(grammar.Nonterminals) + nonterms.sort() + for nonterm in nonterms: + debuglog.info("%-20s : %s", nonterm, " ".join([str(s) for s in grammar.Nonterminals[nonterm]])) + debuglog.info("") + + if check_recursion: + unreachable = grammar.find_unreachable() + for u in unreachable: + errorlog.warning("Symbol '%s' is unreachable",u) + + infinite = grammar.infinite_cycles() + for inf in infinite: + errorlog.error("Infinite recursion detected for symbol '%s'", inf) + errors = 1 + + unused_prec = grammar.unused_precedence() + for term, assoc in unused_prec: + errorlog.error("Precedence rule '%s' defined for unknown symbol '%s'", assoc, term) + errors = 1 + + if errors: + raise YaccError("Unable to build parser") + + # Run the LRGeneratedTable on the grammar + if debug: + errorlog.debug("Generating %s tables", method) + + lr = LRGeneratedTable(grammar,method,debuglog) + + if debug: + num_sr = len(lr.sr_conflicts) + + # Report shift/reduce and reduce/reduce conflicts + if num_sr == 1: + errorlog.warning("1 shift/reduce conflict") + elif num_sr > 1: + errorlog.warning("%d shift/reduce conflicts", num_sr) + + num_rr = len(lr.rr_conflicts) + if num_rr == 1: + errorlog.warning("1 reduce/reduce conflict") + elif num_rr > 1: + errorlog.warning("%d reduce/reduce conflicts", num_rr) + + # Write out conflicts to the output file + if debug and (lr.sr_conflicts or lr.rr_conflicts): + debuglog.warning("") + debuglog.warning("Conflicts:") + debuglog.warning("") + + for state, tok, resolution in lr.sr_conflicts: + debuglog.warning("shift/reduce conflict for %s in state %d resolved as %s", tok, state, resolution) + + already_reported = {} + for state, rule, rejected in lr.rr_conflicts: + if (state,id(rule),id(rejected)) in already_reported: + continue + debuglog.warning("reduce/reduce conflict in state %d resolved using rule (%s)", state, rule) + debuglog.warning("rejected rule (%s) in state %d", rejected,state) + errorlog.warning("reduce/reduce conflict in state %d resolved using rule (%s)", state, rule) + errorlog.warning("rejected rule (%s) in state %d", rejected, state) + already_reported[state,id(rule),id(rejected)] = 1 + + warned_never = [] + for state, rule, rejected in lr.rr_conflicts: + if not rejected.reduced and (rejected not in warned_never): + debuglog.warning("Rule (%s) is never reduced", rejected) + errorlog.warning("Rule (%s) is never reduced", rejected) + warned_never.append(rejected) + + # Write the table file if requested + if write_tables: + lr.write_table(tabmodule,outputdir,signature) + + # Write a pickled version of the tables + if picklefile: + lr.pickle_table(picklefile,signature) + + # Build the parser + lr.bind_callables(pinfo.pdict) + parser = LRParser(lr,pinfo.error_func) + + parse = parser.parse + return parser |