Improve read-modify-write enclosures

Previously inside sync we just called update_job directly, now
we make sure to read the latest verison of the job first.

Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>

diff --git a/pve-zsync b/pve-zsync
index 9a6625df0215769f19f193f37819f478994d9b7b..cfd8c0849b2cbb9463f15b450d9183eb32ad2f79 100755 (executable)
--- a/pve-zsync
+++ b/pve-zsync
@@ -589,16 +589,30 @@ sub sync {
 
        my $date = get_date();
        my $job;
-       eval {
-           $job = get_job($param);
-       };
 
-       if ($job && defined($job->{state}) && $job->{state} eq "syncing") {
-           die "Job --source $param->{source} --name $param->{name} is syncing at the moment";
-       }
+       my $dest;
+       my $source;
+       my $vm_type;
 
-       my $dest = parse_target($param->{dest});
-       my $source = parse_target($param->{source});
+       locked("$CONFIG_PATH/cron_and_state.lock", sub {
+           eval { $job = get_job($param); };
+
+           if ($job && defined($job->{state}) && $job->{state} eq "syncing") {
+               die "Job --source $param->{source} --name $param->{name} is syncing at the moment";
+           }
+
+           $dest = parse_target($param->{dest});
+           $source = parse_target($param->{source});
+
+           $vm_type = vm_exists($source, $param->{source_user});
+           $source->{vm_type} = $vm_type;
+
+           if ($job) {
+               $job->{state} = "syncing";
+               $job->{vm_type} = $vm_type if !$job->{vm_type};
+               update_state($job);
+           }
+       }); #cron and state lock
 
        my $sync_path = sub {
            my ($source, $dest, $job, $param, $date) = @_;
@@ -613,15 +627,6 @@ sub sync {
 
        };
 
-       my $vm_type = vm_exists($source, $param->{source_user});
-       $source->{vm_type} = $vm_type;
-
-       if ($job) {
-           $job->{state} = "syncing";
-           $job->{vm_type} = $vm_type if !$job->{vm_type};
-           locked("$CONFIG_PATH/cron_and_state.lock", sub { update_state($job); });
-       }
-
        eval{
            if ($source->{vmid}) {
                die "VM $source->{vmid} doesn't exist\n" if !$vm_type;
@@ -645,19 +650,25 @@ sub sync {
            }
        };
        if (my $err = $@) {
-           if ($job) {
-               $job->{state} = "error";
-               locked("$CONFIG_PATH/cron_and_state.lock", sub { update_state($job); });
-               print "Job --source $param->{source} --name $param->{name} got an ERROR!!!\nERROR Message:\n";
-           }
+           locked("$CONFIG_PATH/cron_and_state.lock", sub {
+               eval { $job = get_job($param); };
+               if ($job) {
+                   $job->{state} = "error";
+                   update_state($job);
+               }
+           });
+           print "Job --source $param->{source} --name $param->{name} got an ERROR!!!\nERROR Message:\n";
            die "$err\n";
        }
 
-       if ($job) {
-           $job->{state} = "ok";
-           $job->{lsync} = $date;
-           locked("$CONFIG_PATH/cron_and_state.lock", sub { update_state($job); });
-       }
+       locked("$CONFIG_PATH/cron_and_state.lock", sub {
+           eval { $job = get_job($param); };
+           if ($job) {
+               $job->{state} = "ok";
+               $job->{lsync} = $date;
+               update_state($job);
+           }
+       });
     }); #sync lock
 }