From 8520066d7b4782adaf9caa56036071ddb3de86fc Mon Sep 17 00:00:00 2001
From: Harmen <harm@dds.nl>
Date: Mon, 30 Apr 2012 09:57:12 -0600
Subject: [PATCH 1/2] Show problem with 'keys' command with specific command
 sequence.

---
 tests/unit/expire.tcl | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tests/unit/expire.tcl b/tests/unit/expire.tcl
index 82876ddd..56a59f76 100644
--- a/tests/unit/expire.tcl
+++ b/tests/unit/expire.tcl
@@ -141,4 +141,15 @@ start_server {tags {"expire"}} {
         set size2 [r dbsize]
         list $size1 $size2
     } {3 0}
+
+    test {5 keys in, 5 keys out} {
+        r flushdb
+        r set a c
+        r expire a 5
+        r set t c
+        r set e c
+        r set s c
+        r set foo b
+        lsort [r keys *]
+    } {a e foo s t}
 }

From 9311d2b527b0bb3e72e61b143718e6def51491e6 Mon Sep 17 00:00:00 2001
From: Pieter Noordhuis <pcnoordhuis@gmail.com>
Date: Mon, 30 Apr 2012 10:16:20 -0700
Subject: [PATCH 2/2] Use safe dictionary iterator from KEYS

Every matched key in a KEYS call is checked for expiration. When the key
is set to expire, the call to `getExpire` will assert that the key also
exists in the main dictionary. This in turn causes a rehashing step to
be executed. Rehashing a dictionary when there is an iterator active may
result in the iterator emitting duplicate entries, or not emitting some
entries at all. By using a safe iterator, the rehash step is omitted.
---
 src/db.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/db.c b/src/db.c
index 3c75f6ba..e65106a5 100644
--- a/src/db.c
+++ b/src/db.c
@@ -255,7 +255,7 @@ void keysCommand(redisClient *c) {
     unsigned long numkeys = 0;
     void *replylen = addDeferredMultiBulkLength(c);
 
-    di = dictGetIterator(c->db->dict);
+    di = dictGetSafeIterator(c->db->dict);
     allkeys = (pattern[0] == '*' && pattern[1] == '\0');
     while((de = dictNext(di)) != NULL) {
         sds key = dictGetKey(de);