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Python Compiled Bytecode | 2005-10-18 | 30KB | 999 lines

# Source Generated with Decompyle++
# File: in.pyo (Python 2.4)

'''Facility to use the Expat parser to load a minidom instance
from a string or file.

This avoids all the overhead of SAX and pulldom to gain performance.
'''
from xml.dom import xmlbuilder, minidom, Node
from xml.dom import EMPTY_NAMESPACE, EMPTY_PREFIX, XMLNS_NAMESPACE
from xml.parsers import expat
from xml.dom.minidom import _append_child, _set_attribute_node
from xml.dom.NodeFilter import NodeFilter
from xml.dom.minicompat import *
TEXT_NODE = Node.TEXT_NODE
CDATA_SECTION_NODE = Node.CDATA_SECTION_NODE
DOCUMENT_NODE = Node.DOCUMENT_NODE
FILTER_ACCEPT = xmlbuilder.DOMBuilderFilter.FILTER_ACCEPT
FILTER_REJECT = xmlbuilder.DOMBuilderFilter.FILTER_REJECT
FILTER_SKIP = xmlbuilder.DOMBuilderFilter.FILTER_SKIP
FILTER_INTERRUPT = xmlbuilder.DOMBuilderFilter.FILTER_INTERRUPT
theDOMImplementation = minidom.getDOMImplementation()
_typeinfo_map = {
    'CDATA': minidom.TypeInfo(None, 'cdata'),
    'ENUM': minidom.TypeInfo(None, 'enumeration'),
    'ENTITY': minidom.TypeInfo(None, 'entity'),
    'ENTITIES': minidom.TypeInfo(None, 'entities'),
    'ID': minidom.TypeInfo(None, 'id'),
    'IDREF': minidom.TypeInfo(None, 'idref'),
    'IDREFS': minidom.TypeInfo(None, 'idrefs'),
    'NMTOKEN': minidom.TypeInfo(None, 'nmtoken'),
    'NMTOKENS': minidom.TypeInfo(None, 'nmtokens') }

class ElementInfo(NewStyle):
    __slots__ = ('_attr_info', '_model', 'tagName')

    def __init__(self, tagName, model = None):
        self.tagName = tagName
        self._attr_info = []
        self._model = model


    def __getstate__(self):
        return (self._attr_info, self._model, self.tagName)


    def __setstate__(self, state):
        (self._attr_info, self._model, self.tagName) = state


    def getAttributeType(self, aname):
        for info in self._attr_info:
            if info[1] == aname:
                t = info[-2]
                if t[0] == '(':
                    return _typeinfo_map['ENUM']
                else:
                    return _typeinfo_map[info[-2]]
            t[0] == '('

        return minidom._no_type


    def getAttributeTypeNS(self, namespaceURI, localName):
        return minidom._no_type


    def isElementContent(self):
        if self._model:
            type = self._model[0]
            return type not in (expat.model.XML_CTYPE_ANY, expat.model.XML_CTYPE_MIXED)
        else:
            return False


    def isEmpty(self):
        if self._model:
            return self._model[0] == expat.model.XML_CTYPE_EMPTY
        else:
            return False


    def isId(self, aname):
        for info in self._attr_info:
            if info[1] == aname:
                return info[-2] == 'ID'
                continue

        return False


    def isIdNS(self, euri, ename, auri, aname):
        return self.isId((auri, aname))



def _intern(builder, s):
    return builder._intern_setdefault(s, s)


def _parse_ns_name(builder, name):
    parts = name.split(' ')
    intern = builder._intern_setdefault
    if len(parts) == 3:
        (uri, localname, prefix) = parts
        prefix = intern(prefix, prefix)
        qname = '%s:%s' % (prefix, localname)
        qname = intern(qname, qname)
        localname = intern(localname, localname)
    else:
        (uri, localname) = parts
        prefix = EMPTY_PREFIX
        qname = localname = intern(localname, localname)
    return (intern(uri, uri), localname, prefix, qname)


class ExpatBuilder:
    '''Document builder that uses Expat to build a ParsedXML.DOM document
    instance.'''

    def __init__(self, options = None):
        if options is None:
            options = xmlbuilder.Options()

        self._options = options
        if self._options.filter is not None:
            self._filter = FilterVisibilityController(self._options.filter)
        else:
            self._filter = None
            self._finish_start_element = id
        self._parser = None
        self.reset()


    def createParser(self):
        '''Create a new parser object.'''
        return expat.ParserCreate()


    def getParser(self):
        '''Return the parser object, creating a new one if needed.'''
        if not self._parser:
            self._parser = self.createParser()
            self._intern_setdefault = self._parser.intern.setdefault
            self._parser.buffer_text = True
            self._parser.ordered_attributes = True
            self._parser.specified_attributes = True
            self.install(self._parser)

        return self._parser


    def reset(self):
        '''Free all data structures used during DOM construction.'''
        self.document = theDOMImplementation.createDocument(EMPTY_NAMESPACE, None, None)
        self.curNode = self.document
        self._elem_info = self.document._elem_info
        self._cdata = False


    def install(self, parser):
        '''Install the callbacks needed to build the DOM into the parser.'''
        parser.StartDoctypeDeclHandler = self.start_doctype_decl_handler
        parser.StartElementHandler = self.first_element_handler
        parser.EndElementHandler = self.end_element_handler
        parser.ProcessingInstructionHandler = self.pi_handler
        if self._options.entities:
            parser.EntityDeclHandler = self.entity_decl_handler

        parser.NotationDeclHandler = self.notation_decl_handler
        if self._options.comments:
            parser.CommentHandler = self.comment_handler

        if self._options.cdata_sections:
            parser.StartCdataSectionHandler = self.start_cdata_section_handler
            parser.EndCdataSectionHandler = self.end_cdata_section_handler
            parser.CharacterDataHandler = self.character_data_handler_cdata
        else:
            parser.CharacterDataHandler = self.character_data_handler
        parser.ExternalEntityRefHandler = self.external_entity_ref_handler
        parser.XmlDeclHandler = self.xml_decl_handler
        parser.ElementDeclHandler = self.element_decl_handler
        parser.AttlistDeclHandler = self.attlist_decl_handler


    def parseFile(self, file):
        '''Parse a document from a file object, returning the document
        node.'''
        parser = self.getParser()
        first_buffer = True

        try:
            while None:
                buffer = file.read(16 * 1024)
                if not buffer:
                    break

                if first_buffer and self.document.documentElement:
                    self._setup_subset(buffer)

                first_buffer = False
            parser.Parse('', True)
        except ParseEscape:
            pass

        doc = self.document
        self.reset()
        self._parser = None
        return doc


    def parseString(self, string):
        '''Parse a document from a string, returning the document node.'''
        parser = self.getParser()

        try:
            parser.Parse(string, True)
            self._setup_subset(string)
        except ParseEscape:
            pass

        doc = self.document
        self.reset()
        self._parser = None
        return doc


    def _setup_subset(self, buffer):
        '''Load the internal subset if there might be one.'''
        if self.document.doctype:
            extractor = InternalSubsetExtractor()
            extractor.parseString(buffer)
            subset = extractor.getSubset()
            self.document.doctype.internalSubset = subset



    def start_doctype_decl_handler(self, doctypeName, systemId, publicId, has_internal_subset):
        doctype = self.document.implementation.createDocumentType(doctypeName, publicId, systemId)
        doctype.ownerDocument = self.document
        self.document.childNodes.append(doctype)
        self.document.doctype = doctype
        if self._filter and self._filter.acceptNode(doctype) == FILTER_REJECT:
            self.document.doctype = None
            del self.document.childNodes[-1]
            doctype = None
            self._parser.EntityDeclHandler = None
            self._parser.NotationDeclHandler = None

        if has_internal_subset:
            if doctype is not None:
                doctype.entities._seq = []
                doctype.notations._seq = []

            self._parser.CommentHandler = None
            self._parser.ProcessingInstructionHandler = None
            self._parser.EndDoctypeDeclHandler = self.end_doctype_decl_handler



    def end_doctype_decl_handler(self):
        if self._options.comments:
            self._parser.CommentHandler = self.comment_handler

        self._parser.ProcessingInstructionHandler = self.pi_handler
        if not self._elem_info or self._filter:
            self._finish_end_element = id



    def pi_handler(self, target, data):
        node = self.document.createProcessingInstruction(target, data)
        _append_child(self.curNode, node)
        if self._filter and self._filter.acceptNode(node) == FILTER_REJECT:
            self.curNode.removeChild(node)



    def character_data_handler_cdata(self, data):
        childNodes = self.curNode.childNodes
        if self._cdata:
            if self._cdata_continue and childNodes[-1].nodeType == CDATA_SECTION_NODE:
                childNodes[-1].appendData(data)
                return None

            node = self.document.createCDATASection(data)
            self._cdata_continue = True
        elif childNodes and childNodes[-1].nodeType == TEXT_NODE:
            node = childNodes[-1]
            value = node.data + data
            d = node.__dict__
            d['data'] = d['nodeValue'] = value
            return None
        else:
            node = minidom.Text()
            d = node.__dict__
            d['data'] = d['nodeValue'] = data
            d['ownerDocument'] = self.document
        _append_child(self.curNode, node)


    def character_data_handler(self, data):
        childNodes = self.curNode.childNodes
        if childNodes and childNodes[-1].nodeType == TEXT_NODE:
            node = childNodes[-1]
            d = node.__dict__
            d['data'] = d['nodeValue'] = node.data + data
            return None

        node = minidom.Text()
        d = node.__dict__
        d['data'] = d['nodeValue'] = node.data + data
        d['ownerDocument'] = self.document
        _append_child(self.curNode, node)


    def entity_decl_handler(self, entityName, is_parameter_entity, value, base, systemId, publicId, notationName):
        if is_parameter_entity:
            return None

        if not self._options.entities:
            return None

        node = self.document._create_entity(entityName, publicId, systemId, notationName)
        if value is not None:
            child = self.document.createTextNode(value)
            node.childNodes.append(child)

        self.document.doctype.entities._seq.append(node)
        if self._filter and self._filter.acceptNode(node) == FILTER_REJECT:
            del self.document.doctype.entities._seq[-1]



    def notation_decl_handler(self, notationName, base, systemId, publicId):
        node = self.document._create_notation(notationName, publicId, systemId)
        self.document.doctype.notations._seq.append(node)
        if self._filter and self._filter.acceptNode(node) == FILTER_ACCEPT:
            del self.document.doctype.notations._seq[-1]



    def comment_handler(self, data):
        node = self.document.createComment(data)
        _append_child(self.curNode, node)
        if self._filter and self._filter.acceptNode(node) == FILTER_REJECT:
            self.curNode.removeChild(node)



    def start_cdata_section_handler(self):
        self._cdata = True
        self._cdata_continue = False


    def end_cdata_section_handler(self):
        self._cdata = False
        self._cdata_continue = False


    def external_entity_ref_handler(self, context, base, systemId, publicId):
        return 1


    def first_element_handler(self, name, attributes):
        if self._filter is None and not (self._elem_info):
            self._finish_end_element = id

        self.getParser().StartElementHandler = self.start_element_handler
        self.start_element_handler(name, attributes)


    def start_element_handler(self, name, attributes):
        node = self.document.createElement(name)
        _append_child(self.curNode, node)
        self.curNode = node
        if attributes:
            for i in range(0, len(attributes), 2):
                a = minidom.Attr(attributes[i], EMPTY_NAMESPACE, None, EMPTY_PREFIX)
                value = attributes[i + 1]
                d = a.childNodes[0].__dict__
                d['data'] = d['nodeValue'] = value
                d = a.__dict__
                d['value'] = d['nodeValue'] = value
                d['ownerDocument'] = self.document
                _set_attribute_node(node, a)


        if node is not self.document.documentElement:
            self._finish_start_element(node)



    def _finish_start_element(self, node):
        if self._filter:
            if node is self.document.documentElement:
                return None

            filt = self._filter.startContainer(node)
            if filt == FILTER_REJECT:
                Rejecter(self)
            elif filt == FILTER_SKIP:
                Skipper(self)
            else:
                return None
            self.curNode = node.parentNode
            node.parentNode.removeChild(node)
            node.unlink()



    def end_element_handler(self, name):
        curNode = self.curNode
        self.curNode = curNode.parentNode
        self._finish_end_element(curNode)


    def _finish_end_element(self, curNode):
        info = self._elem_info.get(curNode.tagName)
        if info:
            self._handle_white_text_nodes(curNode, info)

        if self._filter:
            if curNode is self.document.documentElement:
                return None

            if self._filter.acceptNode(curNode) == FILTER_REJECT:
                self.curNode.removeChild(curNode)
                curNode.unlink()




    def _handle_white_text_nodes(self, node, info):
        if self._options.whitespace_in_element_content or not info.isElementContent():
            return None

        L = []
        for child in node.childNodes:
            if child.nodeType == TEXT_NODE and not child.data.strip():
                L.append(child)
                continue

        for child in L:
            node.removeChild(child)



    def element_decl_handler(self, name, model):
        info = self._elem_info.get(name)
        if info is None:
            self._elem_info[name] = ElementInfo(name, model)
        else:
            info._model = model


    def attlist_decl_handler(self, elem, name, type, default, required):
        info = self._elem_info.get(elem)
        if info is None:
            info = ElementInfo(elem)
            self._elem_info[elem] = info

        info._attr_info.append([
            None,
            name,
            None,
            None,
            default,
            0,
            type,
            required])


    def xml_decl_handler(self, version, encoding, standalone):
        self.document.version = version
        self.document.encoding = encoding
        if standalone >= 0:
            if standalone:
                self.document.standalone = True
            else:
                self.document.standalone = False



_ALLOWED_FILTER_RETURNS = (FILTER_ACCEPT, FILTER_REJECT, FILTER_SKIP)

class FilterVisibilityController(NewStyle):
    '''Wrapper around a DOMBuilderFilter which implements the checks
    to make the whatToShow filter attribute work.'''
    __slots__ = ('filter',)

    def __init__(self, filter):
        self.filter = filter


    def startContainer(self, node):
        mask = self._nodetype_mask[node.nodeType]
        if self.filter.whatToShow & mask:
            val = self.filter.startContainer(node)
            if val == FILTER_INTERRUPT:
                raise ParseEscape

            if val not in _ALLOWED_FILTER_RETURNS:
                raise ValueError, 'startContainer() returned illegal value: ' + repr(val)

            return val
        else:
            return FILTER_ACCEPT


    def acceptNode(self, node):
        mask = self._nodetype_mask[node.nodeType]
        if self.filter.whatToShow & mask:
            val = self.filter.acceptNode(node)
            if val == FILTER_INTERRUPT:
                raise ParseEscape

            if val == FILTER_SKIP:
                parent = node.parentNode
                for child in node.childNodes[:]:
                    parent.appendChild(child)

                return FILTER_REJECT

            if val not in _ALLOWED_FILTER_RETURNS:
                raise ValueError, 'acceptNode() returned illegal value: ' + repr(val)

            return val
        else:
            return FILTER_ACCEPT

    _nodetype_mask = {
        Node.ELEMENT_NODE: NodeFilter.SHOW_ELEMENT,
        Node.ATTRIBUTE_NODE: NodeFilter.SHOW_ATTRIBUTE,
        Node.TEXT_NODE: NodeFilter.SHOW_TEXT,
        Node.CDATA_SECTION_NODE: NodeFilter.SHOW_CDATA_SECTION,
        Node.ENTITY_REFERENCE_NODE: NodeFilter.SHOW_ENTITY_REFERENCE,
        Node.ENTITY_NODE: NodeFilter.SHOW_ENTITY,
        Node.PROCESSING_INSTRUCTION_NODE: NodeFilter.SHOW_PROCESSING_INSTRUCTION,
        Node.COMMENT_NODE: NodeFilter.SHOW_COMMENT,
        Node.DOCUMENT_NODE: NodeFilter.SHOW_DOCUMENT,
        Node.DOCUMENT_TYPE_NODE: NodeFilter.SHOW_DOCUMENT_TYPE,
        Node.DOCUMENT_FRAGMENT_NODE: NodeFilter.SHOW_DOCUMENT_FRAGMENT,
        Node.NOTATION_NODE: NodeFilter.SHOW_NOTATION }


class FilterCrutch(NewStyle):
    __slots__ = ('_builder', '_level', '_old_start', '_old_end')

    def __init__(self, builder):
        self._level = 0
        self._builder = builder
        parser = builder._parser
        self._old_start = parser.StartElementHandler
        self._old_end = parser.EndElementHandler
        parser.StartElementHandler = self.start_element_handler
        parser.EndElementHandler = self.end_element_handler



class Rejecter(FilterCrutch):
    __slots__ = ()

    def __init__(self, builder):
        FilterCrutch.__init__(self, builder)
        parser = builder._parser
        for name in ('ProcessingInstructionHandler', 'CommentHandler', 'CharacterDataHandler', 'StartCdataSectionHandler', 'EndCdataSectionHandler', 'ExternalEntityRefHandler'):
            setattr(parser, name, None)



    def start_element_handler(self, *args):
        self._level = self._level + 1


    def end_element_handler(self, *args):
        if self._level == 0:
            parser = self._builder._parser
            self._builder.install(parser)
            parser.StartElementHandler = self._old_start
            parser.EndElementHandler = self._old_end
        else:
            self._level = self._level - 1



class Skipper(FilterCrutch):
    __slots__ = ()

    def start_element_handler(self, *args):
        node = self._builder.curNode
        self._old_start(*args)
        if self._builder.curNode is not node:
            self._level = self._level + 1



    def end_element_handler(self, *args):
        if self._level == 0:
            self._builder._parser.StartElementHandler = self._old_start
            self._builder._parser.EndElementHandler = self._old_end
            self._builder = None
        else:
            self._level = self._level - 1
            self._old_end(*args)


_FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID = 'http://xml.python.org/entities/fragment-builder/internal'
_FRAGMENT_BUILDER_TEMPLATE = '<!DOCTYPE wrapper\n  %%s [\n  <!ENTITY fragment-builder-internal\n    SYSTEM "%s">\n%%s\n]>\n<wrapper %%s\n>&fragment-builder-internal;</wrapper>' % _FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID

class FragmentBuilder(ExpatBuilder):
    '''Builder which constructs document fragments given XML source
    text and a context node.

    The context node is expected to provide information about the
    namespace declarations which are in scope at the start of the
    fragment.
    '''

    def __init__(self, context, options = None):
        if context.nodeType == DOCUMENT_NODE:
            self.originalDocument = context
            self.context = context
        else:
            self.originalDocument = context.ownerDocument
            self.context = context
        ExpatBuilder.__init__(self, options)


    def reset(self):
        ExpatBuilder.reset(self)
        self.fragment = None


    def parseFile(self, file):
        '''Parse a document fragment from a file object, returning the
        fragment node.'''
        return self.parseString(file.read())


    def parseString(self, string):
        '''Parse a document fragment from a string, returning the
        fragment node.'''
        self._source = string
        parser = self.getParser()
        doctype = self.originalDocument.doctype
        ident = ''
        if doctype:
            if not doctype.internalSubset:
                pass
            subset = self._getDeclarations()
            if doctype.publicId:
                ident = 'PUBLIC "%s" "%s"' % (doctype.publicId, doctype.systemId)
            elif doctype.systemId:
                ident = 'SYSTEM "%s"' % doctype.systemId

        else:
            subset = ''
        nsattrs = self._getNSattrs()
        document = _FRAGMENT_BUILDER_TEMPLATE % (ident, subset, nsattrs)

        try:
            parser.Parse(document, 1)
        except:
            self.reset()
            raise

        fragment = self.fragment
        self.reset()
        return fragment


    def _getDeclarations(self):
        """Re-create the internal subset from the DocumentType node.

        This is only needed if we don't already have the
        internalSubset as a string.
        """
        doctype = self.context.ownerDocument.doctype
        s = ''
        if doctype:
            for i in range(doctype.notations.length):
                notation = doctype.notations.item(i)
                if s:
                    s = s + '\n  '

                s = '%s<!NOTATION %s' % (s, notation.nodeName)
                if notation.publicId:
                    s = '%s PUBLIC "%s"\n             "%s">' % (s, notation.publicId, notation.systemId)
                    continue
                s = '%s SYSTEM "%s">' % (s, notation.systemId)

            for i in range(doctype.entities.length):
                entity = doctype.entities.item(i)
                if s:
                    s = s + '\n  '

                s = '%s<!ENTITY %s' % (s, entity.nodeName)
                if entity.publicId:
                    s = '%s PUBLIC "%s"\n             "%s"' % (s, entity.publicId, entity.systemId)
                elif entity.systemId:
                    s = '%s SYSTEM "%s"' % (s, entity.systemId)
                else:
                    s = '%s "%s"' % (s, entity.firstChild.data)
                if entity.notationName:
                    s = '%s NOTATION %s' % (s, entity.notationName)

                s = s + '>'


        return s


    def _getNSattrs(self):
        return ''


    def external_entity_ref_handler(self, context, base, systemId, publicId):
        if systemId == _FRAGMENT_BUILDER_INTERNAL_SYSTEM_ID:
            old_document = self.document
            old_cur_node = self.curNode
            parser = self._parser.ExternalEntityParserCreate(context)
            self.document = self.originalDocument
            self.fragment = self.document.createDocumentFragment()
            self.curNode = self.fragment

            try:
                parser.Parse(self._source, 1)
            finally:
                self.curNode = old_cur_node
                self.document = old_document
                self._source = None

            return -1
        else:
            return ExpatBuilder.external_entity_ref_handler(self, context, base, systemId, publicId)



class Namespaces:
    '''Mix-in class for builders; adds support for namespaces.'''

    def _initNamespaces(self):
        self._ns_ordered_prefixes = []


    def createParser(self):
        '''Create a new namespace-handling parser.'''
        parser = expat.ParserCreate(namespace_separator = ' ')
        parser.namespace_prefixes = True
        return parser


    def install(self, parser):
        '''Insert the namespace-handlers onto the parser.'''
        ExpatBuilder.install(self, parser)
        if self._options.namespace_declarations:
            parser.StartNamespaceDeclHandler = self.start_namespace_decl_handler



    def start_namespace_decl_handler(self, prefix, uri):
        '''Push this namespace declaration on our storage.'''
        self._ns_ordered_prefixes.append((prefix, uri))


    def start_element_handler(self, name, attributes):
        if ' ' in name:
            (uri, localname, prefix, qname) = _parse_ns_name(self, name)
        else:
            uri = EMPTY_NAMESPACE
            qname = name
            localname = None
            prefix = EMPTY_PREFIX
        node = minidom.Element(qname, uri, prefix, localname)
        node.ownerDocument = self.document
        _append_child(self.curNode, node)
        self.curNode = node
        if self._ns_ordered_prefixes:
            for prefix, uri in self._ns_ordered_prefixes:
                if prefix:
                    a = minidom.Attr(_intern(self, 'xmlns:' + prefix), XMLNS_NAMESPACE, prefix, 'xmlns')
                else:
                    a = minidom.Attr('xmlns', XMLNS_NAMESPACE, 'xmlns', EMPTY_PREFIX)
                d = a.childNodes[0].__dict__
                d['data'] = d['nodeValue'] = uri
                d = a.__dict__
                d['value'] = d['nodeValue'] = uri
                d['ownerDocument'] = self.document
                _set_attribute_node(node, a)

            del self._ns_ordered_prefixes[:]

        if attributes:
            _attrs = node._attrs
            _attrsNS = node._attrsNS
            for i in range(0, len(attributes), 2):
                aname = attributes[i]
                value = attributes[i + 1]
                if ' ' in aname:
                    (uri, localname, prefix, qname) = _parse_ns_name(self, aname)
                    a = minidom.Attr(qname, uri, localname, prefix)
                    _attrs[qname] = a
                    _attrsNS[(uri, localname)] = a
                else:
                    a = minidom.Attr(aname, EMPTY_NAMESPACE, aname, EMPTY_PREFIX)
                    _attrs[aname] = a
                    _attrsNS[(EMPTY_NAMESPACE, aname)] = a
                d = a.childNodes[0].__dict__
                d['data'] = d['nodeValue'] = value
                d = a.__dict__
                d['ownerDocument'] = self.document
                d['value'] = d['nodeValue'] = value
                d['ownerElement'] = node





class ExpatBuilderNS(Namespaces, ExpatBuilder):
    '''Document builder that supports namespaces.'''

    def reset(self):
        ExpatBuilder.reset(self)
        self._initNamespaces()



class FragmentBuilderNS(Namespaces, FragmentBuilder):
    '''Fragment builder that supports namespaces.'''

    def reset(self):
        FragmentBuilder.reset(self)
        self._initNamespaces()


    def _getNSattrs(self):
        '''Return string of namespace attributes from this element and
        ancestors.'''
        attrs = ''
        context = self.context
        L = []
        while context:
            if hasattr(context, '_ns_prefix_uri'):
                for prefix, uri in context._ns_prefix_uri.items():
                    if prefix in L:
                        continue

                    L.append(prefix)
                    if prefix:
                        declname = 'xmlns:' + prefix
                    else:
                        declname = 'xmlns'
                    if attrs:
                        attrs = "%s\n    %s='%s'" % (attrs, declname, uri)
                        continue
                    attrs = " %s='%s'" % (declname, uri)


            context = context.parentNode
        return attrs



class ParseEscape(Exception):
    '''Exception raised to short-circuit parsing in InternalSubsetExtractor.'''
    pass


class InternalSubsetExtractor(ExpatBuilder):
    '''XML processor which can rip out the internal document type subset.'''
    subset = None

    def getSubset(self):
        '''Return the internal subset as a string.'''
        return self.subset


    def parseFile(self, file):

        try:
            ExpatBuilder.parseFile(self, file)
        except ParseEscape:
            pass



    def parseString(self, string):

        try:
            ExpatBuilder.parseString(self, string)
        except ParseEscape:
            pass



    def install(self, parser):
        parser.StartDoctypeDeclHandler = self.start_doctype_decl_handler
        parser.StartElementHandler = self.start_element_handler


    def start_doctype_decl_handler(self, name, publicId, systemId, has_internal_subset):
        if has_internal_subset:
            parser = self.getParser()
            self.subset = []
            parser.DefaultHandler = self.subset.append
            parser.EndDoctypeDeclHandler = self.end_doctype_decl_handler
        else:
            raise ParseEscape()


    def end_doctype_decl_handler(self):
        s = ''.join(self.subset).replace('\r\n', '\n').replace('\r', '\n')
        self.subset = s
        raise ParseEscape()


    def start_element_handler(self, name, attrs):
        raise ParseEscape()



def parse(file, namespaces = 1):
    """Parse a document, returning the resulting Document node.

    'file' may be either a file name or an open file object.
    """
    if namespaces:
        builder = ExpatBuilderNS()
    else:
        builder = ExpatBuilder()
    if isinstance(file, StringTypes):
        fp = open(file, 'rb')

        try:
            result = builder.parseFile(fp)
        finally:
            fp.close()

    else:
        result = builder.parseFile(file)
    return result


def parseString(string, namespaces = 1):
    '''Parse a document from a string, returning the resulting
    Document node.
    '''
    if namespaces:
        builder = ExpatBuilderNS()
    else:
        builder = ExpatBuilder()
    return builder.parseString(string)


def parseFragment(file, context, namespaces = 1):
    """Parse a fragment of a document, given the context from which it
    was originally extracted.  context should be the parent of the
    node(s) which are in the fragment.

    'file' may be either a file name or an open file object.
    """
    if namespaces:
        builder = FragmentBuilderNS(context)
    else:
        builder = FragmentBuilder(context)
    if isinstance(file, StringTypes):
        fp = open(file, 'rb')

        try:
            result = builder.parseFile(fp)
        finally:
            fp.close()

    else:
        result = builder.parseFile(file)
    return result


def parseFragmentString(string, context, namespaces = 1):
    '''Parse a fragment of a document from a string, given the context
    from which it was originally extracted.  context should be the
    parent of the node(s) which are in the fragment.
    '''
    if namespaces:
        builder = FragmentBuilderNS(context)
    else:
        builder = FragmentBuilder(context)
    return builder.parseString(string)


def makeBuilder(options):
    '''Create a builder based on an Options object.'''
    if options.namespaces:
        return ExpatBuilderNS(options)
    else:
        return ExpatBuilder(options)