Fuzzing fixes, and misc fixes in interp

pfp/fields.py

@@ -257,7 +257,7 @@ def __init__(self, stream=None, metadata_processor=None):
 
         self._pfp__array_idx = None
 
-        self._pfp__snapshot_value = None
+        self._pfp__snapshot_stack = []
 
         if stream is not None:
             self._pfp__parse(stream, save_offset=True)
@@ -302,12 +302,13 @@ def _pfp__snapshot(self, recurse=True):
         """Save off the current value of the field
         """
         if hasattr(self, "_pfp__value"):
-            self._pfp__snapshot_value = self._pfp__value
+            self._pfp__snapshot_stack.append(self._pfp__value)
 
     def _pfp__restore_snapshot(self, recurse=True):
         """Restore a saved value snapshot
         """
-        self._pfp__value = self._pfp__snapshot_value
+        if hasattr(self, "_pfp__value"):
+            self._pfp__value = self._pfp__snapshot_stack.pop()
 
     def _pfp__process_metadata(self):
         """Process the metadata once the entire struct has been
@@ -639,7 +640,11 @@ def __eq__(self, other):
     # set: https://stackoverflow.com/a/1608907
     def __hash__(self):
         #return self._pfp__value.__hash__()
-        return self._pfp__build().__hash__()
+        res = self._pfp__build()
+        # bit fields return an array, not bytes
+        if isinstance(res, list):
+            return str(res).__hash__()
+        return res.__hash__()
 
     def __repr__(self):
         return "{}({!r})".format(self.__class__.__name__, self._pfp__value)
@@ -1083,10 +1088,7 @@ def _pfp__notify_update(self, child=None):
             self._pfp__union_update_other_children = False
 
             new_data = child._pfp__build()
-            try:
-                new_stream = bitwrap.BitwrappedStream(six.BytesIO(new_data))
-            except Exception as e:
-                __import__('pdb').set_trace()
+            new_stream = bitwrap.BitwrappedStream(six.BytesIO(new_data))
             for other_child in self._pfp__children:
                 if other_child is child:
                     continue
@@ -2067,6 +2069,8 @@ def __init__(self, width, field_cls, stream=None, metadata_processor=None):
         self.raw_data = None
         self.implicit = False
 
+        self._pfp__snapshot_raw_stack = []
+
         if stream is not None:
             self._pfp__parse(stream, save_offset=True)
         else:
@@ -2078,7 +2082,7 @@ def _pfp__snapshot(self, recurse=True):
         """Save off the current value of the field
         """
         super(Array, self)._pfp__snapshot(recurse=recurse)
-        self.snapshot_raw_data = self.raw_data
+        self._pfp__snapshot_raw_stack.append(self.raw_data)
 
         if recurse:
             for item in self.items:
@@ -2088,7 +2092,7 @@ def _pfp__restore_snapshot(self, recurse=True):
         """Restore the snapshotted value without triggering any events
         """
         super(Array, self)._pfp__restore_snapshot(recurse=recurse)
-        self.raw_data = self.snapshot_raw_data
+        self.raw_data = self._pfp__snapshot_raw_stack.pop()
 
         if recurse:
             for item in self.items:
@@ -2131,7 +2135,6 @@ def __eq__(self, other):
             res = self._array_to_str()
             return utils.binary(res) == utils.binary(PYSTR(other))
         else:
-            __import__('pdb').set_trace()
             raise Exception("TODO")
 
     def __ne__(self, other):

pfp/fuzz/__init__.py

@@ -71,35 +71,35 @@ def mutate(field, strat_name_or_cls, num=100, at_once=1, yield_changed=False):
     # we don't need these ones anymore
     del to_mutate
 
-    # save the current value of all subfields without
-    # triggering events
-    field._pfp__snapshot(recurse=True)
-
     count = 0
     for x in six.moves.range(num):
-
-        chosen_fields = set()
-        idx_pool = set([x for x in six.moves.xrange(len(with_strats))])
-
-        # modify `at_once` number of fields OR len(with_strats) number of fields,
-        # whichever is lower
-        for at_onces in six.moves.xrange(min(len(with_strats), at_once)):
-            # we'll never pull the same idx from idx_pool more than once
-            # since we're removing the idx after choosing it
-            rand_idx = rand.sample(idx_pool, 1)[0]
-            idx_pool.remove(rand_idx)
-
-            rand_field, field_strat = with_strats[rand_idx]
-            chosen_fields.add(rand_field)
-
-            field_strat.mutate(rand_field)
-
-        if yield_changed:
-            yield field, chosen_fields
-        else:
-            # yield back the original field
-            yield field
-
-        # restore the saved value of all subfields without
+        # save the current value of all subfields without
         # triggering events
-        field._pfp__restore_snapshot(recurse=True)
+        field._pfp__snapshot(recurse=True)
+
+        try:
+            chosen_fields = set()
+            idx_pool = set([x for x in six.moves.xrange(len(with_strats))])
+
+            # modify `at_once` number of fields OR len(with_strats) number of fields,
+            # whichever is lower
+            for at_onces in six.moves.xrange(min(len(with_strats), at_once)):
+                # we'll never pull the same idx from idx_pool more than once
+                # since we're removing the idx after choosing it
+                rand_idx = rand.sample(idx_pool, 1)[0]
+                idx_pool.remove(rand_idx)
+
+                rand_field, field_strat = with_strats[rand_idx]
+                chosen_fields.add(rand_field)
+
+                field_strat.mutate(rand_field)
+
+            if yield_changed:
+                yield field, chosen_fields
+            else:
+                # yield back the original field
+                yield field
+        finally:
+            # restore the saved value of all subfields without
+            # triggering events
+            field._pfp__restore_snapshot(recurse=True)

pfp/interp.py

@@ -174,6 +174,7 @@ def EnumDef(typedef_name, base_cls, enum_vals):
         typedef_name,
         (fields.Enum,),
         {
+            "signed": base_cls.signed,
             "width": base_cls.width,
             "endian": base_cls.endian,
             "format": base_cls.format,
@@ -2321,6 +2322,7 @@ def _handle_enum(self, node, scope, ctxt, stream):
                 curr_val._pfp__set_value(curr_val_parsed._pfp__value)
             elif prev_val is not None:
                 curr_val = prev_val + 1
+            curr_val.signed = enum_cls.signed
             curr_val._pfp__freeze()
             enum_vals[enumerator.name] = curr_val
             enum_vals[fields.PYVAL(curr_val)] = enumerator.name