Document Template accelerations and additonal C Security Manager accelerations

from cAccessControl-review-branch.

doc/CHANGES.txt

@@ -89,6 +89,11 @@ Zope Changes
 
       - API help topics can now document functions as well as classes.
 
+      - Security accelerations in c
+
+      - Accelerated C Document Template handling; Document Templates
+        can now do additional rendering in C, improving performance.
+
     Bugs fixed
 
       - WebDAV: Zope escaped nested object properties derived from

doc/ENVIRONMENT.txt

@@ -148,6 +148,16 @@ Security issues
         2.5+)
 
 
+    ZSP_OWNEROUS_SKIP
+
+        If set, will cause the Zope Security Policy to skip checks relating
+	to ownership, for servers on which ownership is not important.
+
+    ZSP_AUTHENTICATED_SKIP
+
+        If set, will cause the Zope Security Policy to skip checks relating
+	to authentication, for servers which serve only anonymous content.
+
     DISALLOW_LOCAL_PRODUCTS
 
         unknown

lib/python/AccessControl/DTML.py

@@ -84,26 +84,42 @@
 ##############################################################################
 '''Add security system support to Document Templates
 
-$Id: DTML.py,v 1.7 2001/06/21 17:16:31 shane Exp $''' 
-__version__='$Revision: 1.7 $'[11:-2]
+$Id: DTML.py,v 1.8 2001/10/26 16:07:50 matt Exp $''' 
+__version__='$Revision: 1.8 $'[11:-2]
 
 from DocumentTemplate import DT_Util
 import SecurityManagement, string, math, whrandom, random
 import DocumentTemplate.sequence
 
-from ZopeGuards import guarded_getattr, guarded_getitem, _marker
+from ZopeGuards import guarded_getattr, guarded_getitem
 
 class RestrictedDTML:
     '''
     A mix-in for derivatives of DT_String.String that adds Zope security.
     '''
-    def guarded_getattr(self, ob, name, default=_marker):
-        return guarded_getattr(ob, name, default)
+    def guarded_getattr(self, *args): # ob, name [, default]
+        return guarded_getattr(*args)
 
     def guarded_getitem(self, ob, index):
         return guarded_getitem(ob, index)
 
 
+try:
+    #raise ImportError
+    import os
+    if os.environ.get("ZOPE_SECURITY_POLICY", None) == "PYTHON":
+        raise ImportError # :)
+    from cAccessControl import RestrictedDTMLMixin
+except ImportError:
+    pass
+else:
+
+    class RestrictedDTML(RestrictedDTMLMixin, RestrictedDTML):
+        '''
+        A mix-in for derivatives of DT_String.String that adds Zope security.
+        '''
+    
+
 # Allow access to unprotected attributes
 DT_Util.TemplateDict.__allow_access_to_unprotected_subobjects__=1
 string.__allow_access_to_unprotected_subobjects__=1

lib/python/AccessControl/PermissionRole.py

@@ -85,8 +85,8 @@
 __doc__='''Objects that implement Permission-based roles.
 
 
-$Id: PermissionRole.py,v 1.12 2001/10/19 15:12:25 shane Exp $'''
-__version__='$Revision: 1.12 $'[11:-2]
+$Id: PermissionRole.py,v 1.13 2001/10/26 16:07:50 matt Exp $'''
+__version__='$Revision: 1.13 $'[11:-2]
 
 _use_python_impl = 0
 import os

lib/python/AccessControl/SecurityManagement.py

@@ -85,8 +85,21 @@
 __doc__='''short description
 
 
-$Id: SecurityManagement.py,v 1.4 2001/07/02 16:29:55 evan Exp $'''
-__version__='$Revision: 1.4 $'[11:-2]
+$Id: SecurityManagement.py,v 1.5 2001/10/26 16:07:50 matt Exp $'''
+__version__='$Revision: 1.5 $'[11:-2]
+
+def getSecurityManager():
+    """Get a security manager, for the current thread.
+    """
+    thread_id=get_ident()
+    manager=_managers.get(thread_id, None)
+    if manager is None:
+        manager=SecurityManager(
+            thread_id,
+            SecurityContext(SpecialUsers.nobody))
+        _managers[thread_id]=manager
+        
+    return manager
 
 import SpecialUsers
 from SecurityManager import SecurityManager
@@ -110,19 +123,6 @@ def noSecurityManager():
     except: pass
     
 
-def getSecurityManager():
-    """Get a security manager, for the current thread.
-    """
-    thread_id=get_ident()
-    manager=_managers.get(thread_id, None)
-    if manager is None:
-        manager=SecurityManager(
-            thread_id,
-            SecurityContext(SpecialUsers.nobody))
-        _managers[thread_id]=manager
-        
-    return manager
-
 def setSecurityPolicy(aSecurityPolicy):
     """Set the system default security policy. 
 

lib/python/AccessControl/SecurityManager.py

@@ -85,8 +85,8 @@
 __doc__='''short description
 
 
-$Id: SecurityManager.py,v 1.7 2001/10/19 15:12:25 shane Exp $'''
-__version__='$Revision: 1.7 $'[11:-2]
+$Id: SecurityManager.py,v 1.8 2001/10/26 16:07:50 matt Exp $'''
+__version__='$Revision: 1.8 $'[11:-2]
 
 import ZopeSecurityPolicy, os, string
 
@@ -95,7 +95,12 @@ _noroles = ZopeSecurityPolicy._noroles
 try: max_stack_size=string.atoi(os.environ.get('Z_MAX_STACK_SIZE','100'))
 except: max_stack_size=100
 
-_defaultPolicy=ZopeSecurityPolicy.ZopeSecurityPolicy()
+if os.environ.has_key("ZSP_OWNEROUS_SKIP"): ownerous=0
+else: ownerous=1
+if os.environ.has_key("ZSP_AUTHENTICATION_SKIP"): authenticated=0
+else: authenticated=1
+_defaultPolicy=ZopeSecurityPolicy.ZopeSecurityPolicy(ownerous=ownerous,
+    authenticated=authenticated)
 def setSecurityPolicy(aSecurityPolicy):
     """Set the system default security policy. 
 
@@ -107,6 +112,7 @@ def setSecurityPolicy(aSecurityPolicy):
     _defaultPolicy=aSecurityPolicy
     return last
 
+
 class SecurityManager:
     """A security manager provides methods for checking access and managing
     executable context and policies
@@ -116,35 +122,34 @@ class SecurityManager:
         'validate': 1, 'validateValue': 1, 'checkPermission': 1,
         'getUser': 1, 'calledByExecutable': 1
         }
-    
+
     def __init__(self, thread_id, context):
         self._thread_id=thread_id
         self._context=context
-        self._policy=None
+        self._policy=_defaultPolicy
 
     def validate(self, accessed=None, container=None, name=None, value=None,
                  roles=_noroles):
         """Validate access.
 
         Arguments:
-        
+
         accessed -- the object that was being accessed
-        
+
         container -- the object the value was found in
-        
+
         name -- The name used to access the value
-        
+
         value -- The value retrieved though the access.
 
         roles -- The roles of the object if already known.
-        
+
         The arguments may be provided as keyword arguments. Some of these
         arguments may be ommitted, however, the policy may reject access
         in some cases when arguments are ommitted.  It is best to provide
         all the values possible.
         """
         policy=self._policy
-        if policy is None: policy=_defaultPolicy
         if roles is _noroles:
             return policy.validate(accessed, container, name, value,
                                    self._context)
@@ -153,19 +158,19 @@ class SecurityManager:
                                    self._context, roles)
 
     def DTMLValidate(self, accessed=None, container=None, name=None,
-                    value=None,md=None):
+                    value=None, md=None):
 
         """Validate access.
         * THIS EXISTS FOR DTML COMPATIBILITY *
 
         Arguments:
-        
+
         accessed -- the object that was being accessed
-        
+
         container -- the object the value was found in
-        
+
         name -- The name used to access the value
-        
+
         value -- The value retrieved though the access.
 
         md -- multidict for DTML (ignored)
@@ -177,7 +182,6 @@ class SecurityManager:
 
         """
         policy=self._policy
-        if policy is None: policy=_defaultPolicy
         return policy.validate(accessed, container, name, value,
                                self._context)
 
@@ -185,7 +189,6 @@ class SecurityManager:
         """Convenience for common case of simple value validation.
         """
         policy=self._policy
-        if policy is None: policy=_defaultPolicy
         if roles is _noroles:
             return policy.validate(None, None, None, value,
                                    self._context)
@@ -198,13 +201,12 @@ class SecurityManager:
         the given object.
 
         Arguments:
-        
+
         permission -- A permission name
-        
+
         object -- The object being accessed according to the permission
         """
         policy=self._policy
-        if policy is None: policy=_defaultPolicy
         return policy.checkPermission(permission, object,
                                       self._context)
 
@@ -218,7 +220,10 @@ class SecurityManager:
             raise SystemError, 'Excessive recursion'
         stack.append(anExecutableObject)
         p=getattr(anExecutableObject, '_customSecurityPolicy', None)
-        if p is not None: p=p()
+        if p is not None:
+            p=p()
+        else:
+            p=_defaultPolicy
         self._policy=p
 
     def removeContext(self, anExecutableObject,
@@ -245,10 +250,13 @@ class SecurityManager:
         if stack:
             top=stack[-1]
             p=getattr(top, '_customSecurityPolicy', None)
-            if p is not None: p=p()
+            if p is not None:
+                p=p()
+            else:
+                p=_defaultPolicy
             self._policy=p
         else:
-            self._policy=None
+            self._policy=_defaultPolicy
 
     def getUser(self):
         """Get the current authenticated user"""
@@ -260,3 +268,17 @@ class SecurityManager:
         return len(self._context.stack)
 
 
+try:
+    #raise ImportError
+    import os
+    if os.environ.get("ZOPE_SECURITY_POLICY", None) == "PYTHON":
+        raise ImportError # :)
+    from cAccessControl import SecurityManager as cSecurityManager
+except ImportError:
+    pass
+else:
+
+    class SecurityManager(cSecurityManager, SecurityManager):
+        """A security manager provides methods for checking access and managing
+        executable context and policies
+        """

lib/python/AccessControl/ZopeGuards.py

@@ -83,7 +83,7 @@
 # 
 ##############################################################################
 
-__version__='$Revision: 1.7 $'[11:-2]
+__version__='$Revision: 1.8 $'[11:-2]
 
 from RestrictedPython.Guards import safe_builtins, _full_read_guard, \
      full_write_guard
@@ -98,29 +98,41 @@ _marker = []  # Create a new marker object.
 safe_builtins = safe_builtins.copy()
 safe_builtins.update(utility_builtins)
 
-def aq_validate(inst, obj, name, v, validate):
-    return validate(inst, obj, name, v)
-
-def guarded_getattr(inst, name, default=_marker):
-    if name[:1] != '_':
-        # Try to get the attribute normally so that unusual
-        # exceptions are caught early.
-        try: v = getattr(inst, name)
-        except AttributeError:
-            if default is not _marker:
-                return default
-            raise
-        if Containers(type(inst)):
-            # Simple type.  Short circuit.
-            return v
-        validate = getSecurityManager().validate
-        # Filter out the objects we can't access.
-        if hasattr(inst, 'aq_acquire'):
-            return inst.aq_acquire(name, aq_validate, validate)
-        # Or just try to get the attribute directly.
-        if validate(inst, inst, name, v):
-            return v
-    raise Unauthorized, name
+try:
+
+    #raise ImportError
+    import os
+    if os.environ.get("ZOPE_SECURITY_POLICY", None) == "PYTHON":
+        raise ImportError # :)
+    from cAccessControl import aq_validate, guarded_getattr
+
+except ImportError:
+
+    def aq_validate(inst, obj, name, v, validate):
+        return validate(inst, obj, name, v)
+
+
+    def guarded_getattr(inst, name, default=_marker):
+        if name[:1] != '_':
+            # Try to get the attribute normally so that unusual
+            # exceptions are caught early.
+            try: v = getattr(inst, name)
+            except AttributeError:
+                if default is not _marker:
+                    return default
+                raise
+            if Containers(type(inst)):
+                # Simple type.  Short circuit.
+                return v
+            validate = getSecurityManager().validate
+            # Filter out the objects we can't access.
+            if hasattr(inst, 'aq_acquire'):
+                return inst.aq_acquire(name, aq_validate, validate)
+            # Or just try to get the attribute directly.
+            if validate(inst, inst, name, v):
+                return v
+        raise Unauthorized, name
+
 safe_builtins['getattr'] = guarded_getattr
 
 def guarded_hasattr(object, name):

lib/python/AccessControl/ZopeSecurityPolicy.py

@@ -85,8 +85,8 @@
 __doc__='''Define Zope\'s default security policy
 
 
-$Id: ZopeSecurityPolicy.py,v 1.14 2001/10/19 15:12:25 shane Exp $'''
-__version__='$Revision: 1.14 $'[11:-2]
+$Id: ZopeSecurityPolicy.py,v 1.15 2001/10/26 16:07:50 matt Exp $'''
+__version__='$Revision: 1.15 $'[11:-2]
 
 
 _use_python_impl = 0
@@ -119,8 +119,32 @@ if _use_python_impl:
 
     class ZopeSecurityPolicy:
 
-        def __init__(self, ownerous=1):
+        def __init__(self, ownerous=1, authenticated=1):
+            """Create a Zope security policy.
+
+            Two optional keyword arguments may be provided:
+
+            ownerous -- Untrusted users can create code
+                        (e.g. Python scripts or templates),
+                        so check that code owners can access resources.
+                        The argument must have a truth value.
+                        The default is true.
+
+            authenticated -- Allow access to resources based on the
+                        privaledges of the authenticated user.  
+                        The argument must have a truth value.
+                        The default is true.
+
+                        This (somewhat experimental) option can be set
+                        to false on sites that allow only public
+                        (unauthenticated) access. An anticipated
+                        scenario is a ZEO configuration in which some
+                        clients allow only public access and other
+                        clients allow full management.
+            """
+            
             self._ownerous=ownerous
+            self._authenticated=authenticated
 
         def validate(self, accessed, container, name, value, context,
                      roles=_noroles, None=None, type=type, IntType=type(0),
@@ -239,7 +263,8 @@ if _use_python_impl:
 
 
             try:
-                if context.user.allowed(value, roles): return 1
+                if self._authenticated and context.user.allowed(value, roles):
+                    return 1
             except AttributeError: pass
 
             # We don't want someone to acquire if they can't get an unacquired!
@@ -254,4 +279,3 @@ if _use_python_impl:
             if type(roles) is StringType:
                 roles=[roles]
             return context.user.allowed(object, roles)
-

lib/python/DocumentTemplate/DT_If.py

@@ -147,8 +147,8 @@ __doc__='''Conditional insertion
          variable is not reevaluated.
 
 ''' 
-__rcs_id__='$Id: DT_If.py,v 1.16 1999/03/10 00:15:07 klm Exp $'
-__version__='$Revision: 1.16 $'[11:-2]
+__rcs_id__='$Id: DT_If.py,v 1.17 2001/10/26 16:07:50 matt Exp $'
+__version__='$Revision: 1.17 $'[11:-2]
 
 from DT_Util import ParseError, parse_params, name_param, str
 
@@ -192,7 +192,7 @@ class If:
 
         if elses is not None: sections.append(elses)
 
-        self.simple_form=tuple(sections)
+        self.simple_form=('i',)+tuple(sections)
 
 class Unless:
     name='unless'
@@ -204,7 +204,7 @@ class Unless:
         name,expr=name_param(args,'unless',1)
         if expr is None: cond=name
         else: cond=expr.eval
-        self.simple_form=(cond,None,section.blocks)
+        self.simple_form=('i',cond,None,section.blocks)
 
 class Else(Unless):
     # The else tag is included for backward compatibility and is deprecated.

lib/python/DocumentTemplate/DT_Var.py

@@ -217,8 +217,8 @@ Evaluating expressions without rendering results
    
 
 ''' # '
-__rcs_id__='$Id: DT_Var.py,v 1.44 2001/10/02 14:23:32 shane Exp $'
-__version__='$Revision: 1.44 $'[11:-2]
+__rcs_id__='$Id: DT_Var.py,v 1.45 2001/10/26 16:07:50 matt Exp $'
+__version__='$Revision: 1.45 $'[11:-2]
 
 from DT_Util import parse_params, name_param, str
 import re, string, sys
@@ -254,7 +254,11 @@ class Var:
         if len(args)==1 and fmt=='s':
             if expr is None: expr=name
             else: expr=expr.eval
-            self.simple_form=expr,
+            self.simple_form=('v', expr)
+        elif len(args)==2  and fmt=='s' and args.has_key('html_quote'):
+            if expr is None: expr=name
+            else: expr=expr.eval
+            self.simple_form=('v', expr, 'h')
 
     def render(self, md):
         args=self.args
@@ -353,7 +357,7 @@ class Call:
         name, expr = name_param(args,'call',1)
         if expr is None: expr=name
         else: expr=expr.eval
-        self.simple_form=expr,None
+        self.simple_form=('i', expr, None)
 
 
 def url_quote(v, name='(Unknown name)', md={}):

lib/python/DocumentTemplate/cDocumentTemplate.c

@@ -84,7 +84,7 @@
  ****************************************************************************/
 static char cDocumentTemplate_module_documentation[] = 
 ""
-"\n$Id: cDocumentTemplate.c,v 1.39 2001/06/21 19:08:59 shane Exp $"
+"\n$Id: cDocumentTemplate.c,v 1.40 2001/10/26 16:07:50 matt Exp $"
 ;
 
 #include "ExtensionClass.h"
@@ -94,7 +94,7 @@ static PyObject *py___call__, *py___roles__, *py_AUTHENTICATED_USER;
 static PyObject *py_hasRole, *py__proxy_roles, *py_Unauthorized;
 static PyObject *py_Unauthorized_fmt, *py_guarded_getattr;
 static PyObject *py__push, *py__pop, *py_aq_base, *py_renderNS;
-static PyObject *py___class__;
+static PyObject *py___class__, *html_quote;
 
 /* ----------------------------------------------------- */
 
@@ -398,13 +398,29 @@ static PyObject *
 MM_cget(MM *self, PyObject *key, int call)
 {
   long i;
-  PyObject *e, *rr, *tb;
+  PyObject *e, *rr;
 
   UNLESS(-1 != (i=PyList_Size(self->data))) return NULL;
   while (--i >= 0)
     {
-      e=PyList_GetItem(self->data,i);
-      if ((e=PyObject_GetItem(e,key)))
+      e=PyList_GET_ITEM(self->data,i);
+      if (PyDict_Check(e))
+        {
+          e=PyDict_GetItem(e, key);
+          Py_XINCREF(e);
+        }
+      else
+        {
+          UNLESS (e=PyObject_GetItem(e,key)) 
+            {
+              if (PyErr_Occurred() == PyExc_KeyError)
+                PyErr_Clear();
+              else
+                return NULL;
+            }
+        }
+
+      if (e)
 	{
           if (!call) return e;
 
@@ -437,17 +453,8 @@ MM_cget(MM *self, PyObject *key, int call)
             }
 	  return e;
 	}
-      PyErr_Fetch(&e, &rr, &tb);
-      if (e != PyExc_KeyError)
-	{
-	  PyErr_Restore(e,rr,tb);
-	  return NULL;
-	}
-      Py_XDECREF(e);
-      Py_XDECREF(rr);
-      Py_XDECREF(tb);
     }
-  PyErr_SetObject(PyExc_KeyError,key);
+  PyErr_SetObject(PyExc_KeyError, key);
   return NULL;
 }
 
@@ -726,7 +733,7 @@ static int
 render_blocks_(PyObject *blocks, PyObject *rendered,
 	       PyObject *md, PyObject *mda)
 {
-  PyObject *block;
+  PyObject *block, *t;
   int l, i, k=0, append;
 
   if ((l=PyList_Size(blocks)) < 0) return -1;
@@ -735,95 +742,123 @@ render_blocks_(PyObject *blocks, PyObject *rendered,
       block=PyList_GET_ITEM(((PyListObject*)blocks), i);
       append=1;
 
-      if (PyTuple_Check(block))
+      if (PyTuple_Check(block) 
+          && PyTuple_GET_SIZE(block) > 1 
+          && PyTuple_GET_ITEM(block, 0)
+          && PyString_Check(PyTuple_GET_ITEM(block, 0)))
 	{
-	  int bs;
+          switch (PyString_AS_STRING(PyTuple_GET_ITEM(block, 0))[0])
+            {
+            case 'v': /* var  */
+	      t=PyTuple_GET_ITEM(block,1);
 
-	  bs=((PyTupleObject*)block)->ob_size;
-	  
-	  if (bs==1)
-	    {
-	      /* Simple var */
-	      block=PyTuple_GET_ITEM(block,0);
-	      if (PyString_Check(block)) block=PyObject_GetItem(md,block);
-	      else block=PyObject_CallObject(block,mda);
-	      if (block) ASSIGN(block, PyObject_Str(block));
-	      UNLESS(block) return -1;
-	    }
-	  else
-	    {
-	      /* if */
-	      int icond, m;
-	      PyObject *cond, *n, *cache;
-
-	      UNLESS(cache=PyDict_New()) return -1;
-	      cond=PyObject_GetAttr(md,py__push);
-	      if (cond) ASSIGN(cond, PyObject_CallFunction(cond,"O",cache));
-	      Py_DECREF(cache);
-	      if (cond) Py_DECREF(cond);
-	      else return -1;
+	      if (t == NULL) return -1;
+
+	      if (PyString_Check(t)) t=PyObject_GetItem(md, t);
+	      else t=PyObject_CallObject(t, mda);
+
+              if (t == NULL || (! PyString_Check(t)))
+                {
+                  if (t) ASSIGN(t, PyObject_Str(t));
+                  UNLESS(t) return -1;
+                }
+
+              if (PyString_Check(t) 
+                  && PyTuple_GET_SIZE(block) == 3) /* html_quote */
+                {
+                  if (strchr(PyString_AS_STRING(t), '&')
+                      && strchr(PyString_AS_STRING(t), '<')
+                      && strchr(PyString_AS_STRING(t), '>')
+                      && strchr(PyString_AS_STRING(t), '"')
+                      )
+                    ASSIGN(t, PyObject_CallFunction(html_quote, "O", t));
+		    if (t == NULL) return -1;
+                }
+                  
+              block = t;
+              break;
+            case 'i': /* if */
+              {
+                int icond, m, bs;
+                PyObject *cond, *n, *cache;
+
+                bs = PyTuple_GET_SIZE(block) - 1; /* subtract code */
+
+                UNLESS(cache=PyDict_New()) return -1;
+                cond=PyObject_GetAttr(md,py__push);
+                if (cond) ASSIGN(cond, PyObject_CallFunction(cond,"O",cache));
+                Py_DECREF(cache);
+                if (cond) Py_DECREF(cond);
+                else return -1;
 	      
-	      append=0;
-	      m=bs-1;
-	      for (icond=0; icond < m; icond += 2)
-		{
-		  cond=PyTuple_GET_ITEM(block,icond);
-		  if (PyString_Check(cond))
-		    {
-		      /* We have to be careful to handle key errors here */
-		      n=cond;
-		      if ((cond=PyObject_GetItem(md,cond)))
-			{
-			  if (PyDict_SetItem(cache, n, cond) < 0)
-			    {
-			      Py_DECREF(cond);
-			      return if_finally(md,1);
-			    }
-			}
-		      else
-			{
-			  PyObject *t, *v, *tb;
-
-			  PyErr_Fetch(&t, &v, &tb);
-			  if (t != PyExc_KeyError || PyObject_Compare(v,n))
-			    {
-			      PyErr_Restore(t,v,tb);
-			      return if_finally(md,1);
-			    }
-			  Py_XDECREF(t);
-			  Py_XDECREF(v);
-			  Py_XDECREF(tb);
-			  cond=Py_None;
-			  Py_INCREF(cond);
-			}
-		    }
-		  else
-		    UNLESS(cond=PyObject_CallObject(cond,mda))
-		       return if_finally(md,1);
-
-		  if (PyObject_IsTrue(cond))
-		    {
-		      Py_DECREF(cond);
-		      block=PyTuple_GET_ITEM(block,icond+1);
-		      if (block!=Py_None &&
-			 render_blocks_(block, rendered, md, mda) < 0)
-			return if_finally(md,1);
-		      m=-1;
-		      break;
-		    }
-		  else Py_DECREF(cond);
-		}
+                append=0;
+                m=bs-1;
+                for (icond=0; icond < m; icond += 2)
+                  {
+                    cond=PyTuple_GET_ITEM(block,icond+1);
+                    if (PyString_Check(cond))
+                      {
+                        /* We have to be careful to handle key errors here */
+                        n=cond;
+                        if ((cond=PyObject_GetItem(md,cond)))
+                          {
+                            if (PyDict_SetItem(cache, n, cond) < 0)
+                              {
+                                Py_DECREF(cond);
+                                return if_finally(md,1);
+                              }
+                          }
+                        else
+                          {
+                            PyObject *t, *v, *tb;
+                            
+                            PyErr_Fetch(&t, &v, &tb);
+                            if (t != PyExc_KeyError || PyObject_Compare(v,n))
+                              {
+                                PyErr_Restore(t,v,tb);
+                                return if_finally(md,1);
+                              }
+                            Py_XDECREF(t);
+                            Py_XDECREF(v);
+                            Py_XDECREF(tb);
+                            cond=Py_None;
+                            Py_INCREF(cond);
+                          }
+                      }
+                    else
+                      UNLESS(cond=PyObject_CallObject(cond,mda))
+                        return if_finally(md,1);
+                    
+                    if (PyObject_IsTrue(cond))
+                      {
+                        Py_DECREF(cond);
+                        block=PyTuple_GET_ITEM(block,icond+1+1);
+                        if (block!=Py_None &&
+                            render_blocks_(block, rendered, md, mda) < 0)
+                          return if_finally(md,1);
+                        m=-1;
+                        break;
+                      }
+                    else Py_DECREF(cond);
+                  }
 		if (icond==m)
 		  {
-		    block=PyTuple_GET_ITEM(block,icond);
+		    block=PyTuple_GET_ITEM(block,icond+1);
 		    if (block!=Py_None &&
-		       render_blocks_(block, rendered, md, mda) < 0)
+                        render_blocks_(block, rendered, md, mda) < 0)
 		      return if_finally(md,1);
 		  }
-
+                
 		if (if_finally(md,0) == -2) return -1;
-	    }
-	}
+              }
+              break;
+            default:
+              PyErr_Format(PyExc_ValueError,
+                           "Invalid DTML command code, %s",
+                           PyString_AS_STRING(PyTuple_GET_ITEM(block, 0)));
+              return -1;
+            }
+        }
       else if (PyString_Check(block))
 	{
 	  Py_INCREF(block);
@@ -904,10 +939,14 @@ void
 initcDocumentTemplate(void)
 {
   PyObject *m, *d;
-  char *rev="$Revision: 1.39 $";
+  char *rev="$Revision: 1.40 $";
 
   DictInstanceType.ob_type=&PyType_Type;
 
+  UNLESS (html_quote = PyImport_ImportModule("html_quote")) return;
+  ASSIGN(html_quote, PyObject_GetAttrString(html_quote, "html_quote"));
+  UNLESS (html_quote) return;
+
   UNLESS(py_isDocTemp=PyString_FromString("isDocTemp")) return;
   UNLESS(py_renderNS=PyString_FromString("__render_with_namespace__")) return;
   UNLESS(py_blocks=PyString_FromString("blocks")) return;
@@ -946,6 +985,4 @@ initcDocumentTemplate(void)
   PyDict_SetItemString(d, "__version__",
 		       PyString_FromStringAndSize(rev+11,strlen(rev+11)-2));
 
-  if (PyErr_Occurred())
-    Py_FatalError("can't initialize module cDocumentTemplate");
 }