Op Some Codes

blockimgdiff.py

@@ -26,13 +26,17 @@ from tempfile import mkstemp
 import threading
 from collections import deque, OrderedDict
 from hashlib import sha1
-
-import common
 from rangelib import RangeSet
 
 __all__ = ["EmptyImage", "DataImage", "BlockImageDiff"]
 
 
+class Settings(object):
+    # Stash size cannot exceed cache_size * threshold.
+    cache_size = None
+    stash_threshold = 0.8
+
+
 def compute_patch(src, tgt, imgdiff=False):
     srcfd, srcfile = mkstemp(prefix="src-")
     tgtfd, tgtfile = mkstemp(prefix="tgt-")
@@ -327,7 +331,7 @@ class BlockImageDiff(object):
             self.ImproveVertexSequence()
 
         # Ensure the runtime stash size is under the limit.
-        if self.version >= 2 and common.OPTIONS.cache_size is not None:
+        if self.version >= 2 and Settings.cache_size is not None:
             self.ReviseStashSize()
 
         # Double-check our work.
@@ -551,14 +555,14 @@ class BlockImageDiff(object):
                 out.append("".join(free_string))
                 stashed_blocks -= free_size
 
-            if self.version >= 2 and common.OPTIONS.cache_size is not None:
+            if self.version >= 2 and Settings.cache_size is not None:
                 # Sanity check: abort if we're going to need more stash space than
                 # the allowed size (cache_size * threshold). There are two purposes
                 # of having a threshold here. a) Part of the cache may have been
                 # occupied by some recovery logs. b) It will buy us some time to deal
                 # with the oversize issue.
-                cache_size = common.OPTIONS.cache_size
-                stash_threshold = common.OPTIONS.stash_threshold
+                cache_size = Settings.cache_size
+                stash_threshold = Settings.stash_threshold
                 max_allowed = cache_size * stash_threshold
                 assert max_stashed_blocks * self.tgt.blocksize < max_allowed, \
                     'Stash size %d (%d * %d) exceeds the limit %d (%d * %.2f)' % (
@@ -608,7 +612,7 @@ class BlockImageDiff(object):
 
         if self.version >= 2:
             self._max_stashed_size = max_stashed_blocks * self.tgt.blocksize
-            OPTIONS = common.OPTIONS
+            OPTIONS = Settings
             if OPTIONS.cache_size is not None:
                 max_allowed = OPTIONS.cache_size * OPTIONS.stash_threshold
                 print("max stashed blocks: %d  (%d bytes), "
@@ -636,8 +640,8 @@ class BlockImageDiff(object):
 
         # Compute the maximum blocks available for stash based on /cache size and
         # the threshold.
-        cache_size = common.OPTIONS.cache_size
-        stash_threshold = common.OPTIONS.stash_threshold
+        cache_size = Settings.cache_size
+        stash_threshold = Settings.stash_threshold
         max_allowed = cache_size * stash_threshold / self.tgt.blocksize
 
         stashed_blocks = 0
@@ -1129,7 +1133,7 @@ class BlockImageDiff(object):
                 return
 
             pieces = 0
-            cache_size = common.OPTIONS.cache_size
+            cache_size = Settings.cache_size
             split_threshold = 0.125
             max_blocks_per_transfer = int(cache_size * split_threshold /
                                           self.tgt.blocksize)

common.py

@@ -1,12 +0,0 @@
-import blockimgdiff
-
-
-class Options(object):
-    def __init__(self):
-        # Stash size cannot exceed cache_size * threshold.
-        self.cache_size = None
-        self.stash_threshold = 0.8
-
-
-OPTIONS = Options()
-DataImage = blockimgdiff.DataImage

utils.py

@@ -3,8 +3,8 @@ from __future__ import print_function
 import struct
 from os.path import exists
 import os, errno, tempfile
-import common
 import blockimgdiff
+DataImage = blockimgdiff.DataImage
 import sparse_img
 from threading import Thread
 from random import randint, choice