[PATCH] testbot/LibvirtTool: Fix FatalError() when the VM status is not as expected.

[Francois Gouget]

If the VM Status is not in the expected state then it no longer
belongs to this process. So don't even try to save it as that could
cause interference. Also don't notify the administrator about putting
it offline since that will not be happening.
However if the VM is merely in maintenance mode that means the tool is
being debugged so proceed normally except for the VM Status which must
not be modified to avoid inteference from the scheduler.

Signed-off-by: Francois Gouget 
---
 testbot/bin/LibvirtTool.pl | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/testbot/bin/LibvirtTool.pl b/testbot/bin/LibvirtTool.pl
index f031c78c8..5c3906503 100755
--- a/testbot/bin/LibvirtTool.pl
+++ b/testbot/bin/LibvirtTool.pl
@@ -166,23 +166,31 @@ sub FatalError($)
   my ($ErrMessage) = @_;
   Error $ErrMessage;

+  # Get the up-to-date VM status
+  $VM = CreateVMs()->GetItem($VMKey);
+
   # Put the VM offline or mark it for maintenance
   my $Errors = ($VM->Errors || 0) + 1;
   my $NewStatus = $Errors < $MaxVMErrors ? "offline" : "maintenance";

-  $VM = CreateVMs()->GetItem($VMKey);
-  # Put the VM offline if nobody else modified its status before us
-  if ($VM->Status eq $CurrentStatus)
+  if ($VM->Status eq "maintenance")
   {
-    $VM->Status($NewStatus);
-    $VM->ChildDeadline(undef);
-    $VM->ChildPid(undef);
-    $VM->Errors($Errors);
+    # Still proceed with changing the non-Status fields and notifying the
+    # administrator to allow for error handling debugging.
+  }
+  elsif ($VM->Status ne $CurrentStatus)
+  {
+    LogMsg "Not updating the VM because its status changed: ". $VM->Status ." != $CurrentStatus\n";
+    exit 1;
   }
   else
   {
-    $NewStatus = "";
+    $VM->Status($NewStatus);
   }
+  $VM->ChildDeadline(undef);
+  $VM->ChildPid(undef);
+  $VM->Errors($Errors);
+
   my ($ErrProperty, $SaveErrMessage) = $VM->Save();
   if (defined $SaveErrMessage)
   {
@@ -198,7 +206,7 @@ sub FatalError($)
   elsif ($NewStatus eq "maintenance")
   {
     NotifyAdministrator("The $VMKey VM needs maintenance",
-                        "Got ". $VM->Errors ." consecutive errors working on the $VMKey VM:\n".
+                        "Got $Errors consecutive errors working on the $VMKey VM:\n".
                         "\n$ErrMessage\n".
                         "An administrator needs to look at it and to put it back online.");
   }