Changeset 20 for lib/bletchley/blobtools.py

Timestamp:

12/06/12 18:35:28 (12 years ago)

Author:

tmorgan

Message:

added simple encode/decode command line tools

fixed problem with percent encoding by allowing for a third result of tests

implemented (untested) resumption of decryption for POA

more POA documentation and logging

File:

• lib/bletchley/blobtools.py (modified) (4 diffs)

lib/bletchley/blobtools.py

@@ -41 +41 @@
     def isExample(self, blob):
         sblob = frozenset(blob)
-        return ((self.charset == None or sblob.issubset(self.charset)) and self.extraTests(blob))
+        if self.charset != None and not sblob.issubset(self.charset):
+            return False
+        return self.extraTests(blob)
     
     def extraTests(self, blob):
+        """May return True, False, or None, for is an example, isn't an
+        example, or unknown, respectively. 
+
+        """
         return True
 
@@ -254 +260 @@
         chunks = blob.split('%')
         if len(chunks) < 2:
-            return False
+            return None
         for c in chunks[1:]:
             if len(c) < 2:
@@ -320 +326 @@
 
 def possibleEncodings(blob):
-    ret_val = set()
+    likely = set()
+    possible = set()
     for name,encoding in encodings.items():
-        if encoding.isExample(blob):
-            ret_val.add(name)
-    return ret_val
+        result = encoding.isExample(blob)
+        if result == True:
+            likely.add(name)
+        elif result == None:
+            possible.add(name)
+    return likely,possible
 
 
 def encodingIntersection(blobs):
     ret_val = set(encodings.keys())
+    p = set(encodings.keys())
     for b in blobs:
-        ret_val &= possibleEncodings(b)
-
-    return ret_val
+        likely,possible = possibleEncodings(b)
+        ret_val &= likely | possible
+        p &= possible
+    return ret_val - p
 
 
@@ -404 +416 @@
 
 
+#XXX: move this to buffertools
 def smartPermutateBlobs(blobs, block_size=8):
     """