From: Brian Warner <warner@lothar.com>
Date: Sun, 28 Aug 2011 07:41:03 +0000 (-0700)
Subject: MutableFileNode.set_downloader_hints: never depend upon order of dict.values()
X-Git-Tag: allmydata-tahoe-1.9.0a2~75
X-Git-Url: https://git.rkrishnan.org/reliability?a=commitdiff_plain;h=0f1d674d76490f71c02116bcfdc0620cd758c975;p=tahoe-lafs%2Ftahoe-lafs.git

MutableFileNode.set_downloader_hints: never depend upon order of dict.values()

The old code was calculating the "extension parameters" (a list) from the
downloader hints (a dictionary) with hints.values(), which is not stable, and
would result in corrupted filecaps (with the 'k' and 'segsize' hints
occasionally swapped). The new code always uses [k,segsize].
---

diff --git a/src/allmydata/mutable/filenode.py b/src/allmydata/mutable/filenode.py
index 59438b87..02f99b64 100644
--- a/src/allmydata/mutable/filenode.py
+++ b/src/allmydata/mutable/filenode.py
@@ -701,7 +701,7 @@ class MutableFileNode:
 
     def set_downloader_hints(self, hints):
         self._downloader_hints = hints
-        extensions = hints.values()
+        extensions = [ hints["k"], hints["segsize"] ]
         self._uri.set_extension_params(extensions)