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diff --git a/rpkid/rpki/sax_utils.py b/rpkid/rpki/sax_utils.py
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+# $Id$
+
+# Copyright (C) 2007--2008  American Registry for Internet Numbers ("ARIN")
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND ARIN DISCLAIMS ALL WARRANTIES WITH
+# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+# AND FITNESS.  IN NO EVENT SHALL ARIN BE LIABLE FOR ANY SPECIAL, DIRECT,
+# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+# OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+# PERFORMANCE OF THIS SOFTWARE.
+
+"""SAX utilities."""
+
+import xml.sax, lxml.sax
+
+class handler(xml.sax.handler.ContentHandler):
+  """SAX handler for RPKI protocols.
+
+  This class provides some basic amenities for parsing protocol XML of
+  the kind we use in the RPKI protocols, including whacking all the
+  protocol element text into US-ASCII, simplifying accumulation of
+  text fields, and hiding some of the fun relating to XML namespaces.
+
+  General assumption: by the time this parsing code gets invoked, the
+  XML has already passed RelaxNG validation, so we only have to check
+  for errors that the schema can't catch, and we don't have to play as
+  many XML namespace games.
+  """
+
+  def __init__(self):
+    """Initialize SAX handler."""
+    self.text = ""
+    self.stack = []
+
+  def startElementNS(self, name, qname, attrs):
+    """Redirect startElementNS() events to startElement()."""
+    return self.startElement(name[1], attrs)
+
+  def endElementNS(self, name, qname):
+    """Redirect endElementNS() events to endElement()."""
+    return self.endElement(name[1])
+
+  def characters(self, content):
+    """Accumulate a chuck of element content (text)."""
+    self.text += content
+
+  def startElement(self, name, attrs):
+    """Handle startElement() events.
+
+    We maintain a stack of nested elements under construction so that
+    we can feed events directly to the current element rather than
+    having to pass them through all the nesting elements.
+
+    If the stack is empty, this event is for the outermost element, so
+    we call a virtual method to create the corresponding object and
+    that's the object we'll be returning as our final result.
+    """
+    a = dict()
+    for k,v in attrs.items():
+      if isinstance(k, tuple):
+        if k == ("http://www.w3.org/XML/1998/namespace", "lang"):
+          k = "xml:lang"
+        else:
+          assert k[0] is None
+          k = k[1]
+      a[k.encode("ascii")] = v.encode("ascii")
+    if len(self.stack) == 0:
+      assert not hasattr(self, "result")
+      self.result = self.create_top_level(name, a)
+      self.stack.append(self.result)
+    self.stack[-1].startElement(self.stack, name, a)
+
+  def endElement(self, name):
+    """Handle endElement() events.
+
+    Mostly this means handling any accumulated element text.
+    """
+    text = self.text.encode("ascii").strip()
+    self.text = ""
+    self.stack[-1].endElement(self.stack, name, text)
+
+  @classmethod
+  def saxify(cls, elt):
+    """Create a one-off SAX parser, parse an ETree, return the result.
+    """
+    self = cls()
+    lxml.sax.saxify(elt, self)
+    return self.result