1 files changed, 118 insertions, 0 deletions
diff --git a/lib/kross/python/scripts/RestrictedPython/Eval.py b/lib/kross/python/scripts/RestrictedPython/Eval.py
new file mode 100644
index 000000000..841067a13
--- /dev/null
+++ b/lib/kross/python/scripts/RestrictedPython/Eval.py
@@ -0,0 +1,118 @@
+##############################################################################
+#
+# Copyright (c) 2001 Zope Corporation and Contributors. All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.0 (ZPL).  A copy of the ZPL should accompany this distribution.
+# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+# FOR A PARTICULAR PURPOSE
+#
+##############################################################################
+"""Restricted Python Expressions
+
+$Id: Eval.py 24763 2004-05-17 05:59:28Z philikon $
+"""
+
+__version__='$Revision: 1.6 $'[11:-2]
+
+from RestrictedPython import compile_restricted_eval
+
+from string import translate, strip
+import string
+
+nltosp = string.maketrans('\r\n','  ')
+
+default_guarded_getattr = getattr # No restrictions.
+
+def default_guarded_getitem(ob, index):
+    # No restrictions.
+    return ob[index]
+
+PROFILE = 0
+
+class RestrictionCapableEval:
+    """A base class for restricted code."""
+    
+    globals = {'__builtins__': None}
+    rcode = None  # restricted
+    ucode = None  # unrestricted
+    used = None
+
+    def __init__(self, expr):
+        """Create a restricted expression
+
+        where:
+
+          expr -- a string containing the expression to be evaluated.
+        """
+        expr = strip(expr)
+        self.__name__ = expr
+        expr = translate(expr, nltosp)
+        self.expr = expr
+        self.prepUnrestrictedCode()  # Catch syntax errors.
+
+    def prepRestrictedCode(self):
+        if self.rcode is None:
+            if PROFILE:
+                from time import clock
+                start = clock()
+            co, err, warn, used = compile_restricted_eval(
+                self.expr, '<string>')
+            if PROFILE:
+                end = clock()
+                print 'prepRestrictedCode: %d ms for %s' % (
+                    (end - start) * 1000, `self.expr`)
+            if err:
+                raise SyntaxError, err[0]
+            self.used = tuple(used.keys())
+            self.rcode = co
+
+    def prepUnrestrictedCode(self):
+        if self.ucode is None:
+            # Use the standard compiler.
+            co = compile(self.expr, '<string>', 'eval')
+            if self.used is None:
+                # Examine the code object, discovering which names
+                # the expression needs.
+                names=list(co.co_names)
+                used={}
+                i=0
+                code=co.co_code
+                l=len(code)
+                LOAD_NAME=101
+                HAVE_ARGUMENT=90
+                while(i < l):
+                    c=ord(code[i])
+                    if c==LOAD_NAME:
+                        name=names[ord(code[i+1])+256*ord(code[i+2])]
+                        used[name]=1
+                        i=i+3
+                    elif c >= HAVE_ARGUMENT: i=i+3
+                    else: i=i+1
+                self.used=tuple(used.keys())
+            self.ucode=co
+
+    def eval(self, mapping):
+        # This default implementation is probably not very useful. :-(
+        # This is meant to be overridden.
+        self.prepRestrictedCode()
+        code = self.rcode
+        d = {'_getattr_': default_guarded_getattr,
+             '_getitem_': default_guarded_getitem}
+        d.update(self.globals)
+        has_key = d.has_key
+        for name in self.used:
+            try:
+                if not has_key(name):
+                    d[name] = mapping[name]
+            except KeyError:
+                # Swallow KeyErrors since the expression
+                # might not actually need the name.  If it
+                # does need the name, a NameError will occur.
+                pass
+        return eval(code, d)
+
+    def __call__(self, **kw):
+        return self.eval(kw)