Merge pull request #18 from tahoe-lafs/17.remove-pyutil-dependency

remove pyutil dependency

Fixes: ticket:17

setup.py

@@ -60,11 +60,14 @@
     long_description=open('README.rst', 'rU').read(),
     url="https://github.com/tahoe-lafs/zfec",
     install_requires=[
-        "pyutil >= 3.0.0",
         "argparse >= 0.8 ; python_version <= '2.7'",
         # note to self: single-quotes on the '2.7' are ok:
         # https://github.com/pypa/packaging/blob/16.8/packaging/markers.py#L121
 ],
+    extras_require={
+        "bench": ["pyutil >= 3.0.0"],
+        "test": ["twisted", "setuptools_trial", "pyutil >= 3.0.0"],
+    },
     ext_modules=extensions,
     cmdclass=versioneer.get_cmdclass(),
 )

tox.ini

@@ -3,9 +3,7 @@ envlist = py27,py35,py36
 skip_missing_interpreters = True
 
 [testenv]
-deps = pyutil
-       twisted
-       setuptools_trial
+deps = .[test]
 usedevelop = True
 
 commands =

zfec/filefec.py

@@ -1,14 +1,35 @@
 from __future__ import print_function
 import array, os, struct
 from base64 import b32encode
-from pyutil import fileutil
-from pyutil.mathutil import pad_size, log_ceil
 
 import zfec
 from zfec import easyfec
 
 CHUNKSIZE = 4096
 
+def pad_size(n, k):
+    """
+    The smallest number that has to be added to n to equal a multiple of k.
+    """
+    if n%k:
+        return k - n%k
+    else:
+        return 0
+
+def log_ceil(n, b):
+    """
+    The smallest integer k such that b^k >= n.
+
+    log_ceil(n, 2) is the number of bits needed to store any of n values, e.g.
+    the number of bits needed to store any of 128 possible values is 7.
+    """
+    p = 1
+    k = 0
+    while p < n:
+        p *= b
+        k += 1
+    return k
+
 def ab(x): # debuggery
     if len(x) >= 3:
         return "%s:%s" % (len(x), b32encode(x[-3:]),)
@@ -224,7 +245,10 @@ def cb(blocks, length):
             for fn in fns:
                 if verbose:
                     print("Cleaning up: trying to remove %r..." % (fn,))
-                fileutil.remove_if_possible(fn)
+                try:
+                    os.remove(fn)
+                except EnvironmentError:
+                    pass
             return 1
     if verbose:
         print()