replaced some common string ops with util funcs (repeat_string, right_pad_string)

2 files changed, 20 insertions, 11 deletions

diff --git a/passlib/utils/__init__.py b/passlib/utils/__init__.py
index 785afe0..d2fbd3f 100644
--- a/passlib/utils/__init__.py
+++ b/passlib/utils/__init__.py
@@ -481,14 +481,27 @@ def int_to_bytes(value, count):
         for s in irange(8*count-8,-8,-8)
     )
 
-def repeat_bytes(source, size):
-    "repeat or truncate <source> bytes, so it has length <size>"
+def repeat_string(source, size):
+    "repeat or truncate <source> string, so it has length <size>"
     cur = len(source)
-    if size <= cur:
-        return source[:size]
-    else:
+    if size > cur:
         mult = (size+cur-1)//cur
         return (source*mult)[:size]
+    else:
+        return source[:size]
+
+_BNULL = b("\x00")
+_UNULL = u("\x00")
+
+def right_pad_string(source, size, pad=None):
+    "right-pad or truncate <source> string, so it has length <size>"
+    cur = len(source)
+    if size > cur:
+        if pad is None:
+            pad = _UNULL if isinstance(source, unicode) else _BNULL
+        return source+pad*(size-cur)
+    else:
+        return source[:size]
 
 #=============================================================================
 # encoding helpers
diff --git a/passlib/utils/_blowfish/base.py b/passlib/utils/_blowfish/base.py
index 9be048b..fdbead1 100644
--- a/passlib/utils/_blowfish/base.py
+++ b/passlib/utils/_blowfish/base.py
@@ -5,6 +5,7 @@
 #core
 import struct
 #pkg
+from passlib.utils import repeat_string
 #local
 __all__ = [
     "BlowfishEngine",
@@ -328,12 +329,7 @@ class BlowfishEngine(object):
             return [0]*size
 
         # repeat data until it fills up 4*size bytes
-        needed = size<<2
-        if dlen > needed:
-            data = data[:needed]
-        elif dlen < needed:
-            count = (needed+dlen-1)//dlen
-            data = (data * count)[:needed]
+        data = repeat_string(data, size<<2)
 
         # unpack
         return struct.unpack(">%dI" % (size,), data)