[PATCH] fix job_master crash when lock acquisition fails

[Eric Wong]

JobMaster expects arrays to be returned by ->grab_files_*
methods, so we need to return an array regardless of lock
acquisition succeeding or failing.

Link: https://groups.google.com/d/msgid/mogile/e10ccdf3-7c02-4336...@googlegroups.com
---
lib/MogileFS/Store.pm | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/MogileFS/Store.pm b/lib/MogileFS/Store.pm
index c16aec1..6ba4c7c 100644
--- a/lib/MogileFS/Store.pm
+++ b/lib/MogileFS/Store.pm
@@ -1723,7 +1723,7 @@ sub grab_queue_chunk {
my $tries = 3;
my $work;

- return 0 unless $self->lock_queue($queue);
+ return () unless $self->lock_queue($queue);

my $extwhere = shift || '';
my $fields = 'fid, nexttry, failcount';