Mercurial > paraspace

changeset 68:b7432d6f7e93

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
adler32
author Thinker K.F. Li <thinker@codemud.net>
date Wed, 29 Jun 2011 19:56:24 +0800
parents 9504ad530dbf
children d07fd67e2b08
files paraspace/tools.py
diffstat 1 files changed, 12 insertions(+), 0 deletions(-) [+]
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/paraspace/tools.py	Wed Jun 29 19:56:24 2011 +0800
@@ -0,0 +1,12 @@
+base = 65521
+
+def adler32(adler, buf, offset, sz):
+    sum1 = adler & 0xffff
+    sum2 = (adler >> 16) & 0xffff
+    for off in range(offset, offset + sz):
+        sum1 = (sum1 + ord(buf[off])) % base
+        sum2 = (sum2 + sum1) % base
+        pass
+    r = (sum2 << 16) | sum1
+    return r
+