[Libguestfs] [PATCH 3/3] RHEV: Cleanup volumes on unclean shutdown

[Matthew Booth]

Currently image files will be left on the export domain if a conversion fails.
It isn't possible to delete these through the RHEV UI, requiring an
administrator to clean them up manually.

This change causes images to be written to a temporary directory on the export
domain, and moved to the correct location immediately before writing the OVF
file. It also removes this temporary directory automatically on unclean
shutdown. This means that a failed conversion shouldn't leave anything on the
export domain. Even if it does, for example because of a power failure, the
temporary files are clearly separated in their own directory.

Fixes RHBZ#596071
---
 lib/Sys/VirtV2V/Target/RHEV.pm |   63 ++++++++++++++++++++++++++++++++++++++--
 1 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/lib/Sys/VirtV2V/Target/RHEV.pm b/lib/Sys/VirtV2V/Target/RHEV.pm
index b80c66a..f7608a2 100644
--- a/lib/Sys/VirtV2V/Target/RHEV.pm
+++ b/lib/Sys/VirtV2V/Target/RHEV.pm
@@ -160,6 +160,8 @@ sub DESTROY
 
 package Sys::VirtV2V::Target::RHEV::Vol;
 
+use File::Path;
+use File::Temp qw(tempdir);
 use POSIX;
 
 use Sys::VirtV2V::UserMessage qw(user_message);
@@ -167,6 +169,8 @@ use Sys::VirtV2V::UserMessage qw(user_message);
 use Locale::TextDomain 'virt-v2v';
 
 our %vols_by_path;
+our @vols;
+our $tmpdir;
 
 sub _new
 {
@@ -188,12 +192,25 @@ sub _new
     $self->{voluuid}    = $voluuid;
     $self->{domainuuid} = $domainuuid;
 
-    $self->{dir}  = "$mountdir/$domainuuid/images/$imageuuid";
-    $self->{path} = $self->{dir}."/$voluuid";
+    my $root = "$mountdir/$domainuuid";
+    unless (defined($tmpdir)) {
+        my $nfs = Sys::VirtV2V::Target::RHEV::NFSHelper->new(sub {
+            print tempdir("v2v.XXXXXXXX", DIR => $root);
+        });
+        my $fromchild = $nfs->{fromchild};
+        ($tmpdir) = <$fromchild>;
+        $nfs->check_exit();
+    }
+
+    $self->{dir}  = "$root/images/$imageuuid";
+    $self->{tmpdir} = "$tmpdir/$imageuuid";
+
+    $self->{path} = $self->{tmpdir}."/$voluuid";
 
     $self->{creation} = time();
 
     $vols_by_path{$self->{path}} = $self;
+    push(@vols, $self);
 
     return $self;
 }
@@ -263,7 +280,7 @@ sub open
     $self->{written} = 0;
 
     $self->{writer} = Sys::VirtV2V::Target::RHEV::NFSHelper->new(sub {
-        my $dir = $self->{dir};
+        my $dir = $self->{tmpdir};
         my $path = $self->{path};
 
         mkdir($dir)
@@ -352,6 +369,33 @@ sub close
     delete($self->{written});
 }
 
+sub _move_vols
+{
+    my $class = shift;
+
+    foreach my $vol (@vols) {
+        rename($vol->{tmpdir}, $vol->{dir})
+            or die(user_message(__x("Unable to move volume from temporary ".
+                                    "location {tmpdir} to {dir}",
+                                    tmpdir => $vol->{tmpdir},
+                                    dir => $vol->{dir})));
+    }
+
+    $class->_cleanup();
+}
+
+sub _cleanup
+{
+    my $class = shift;
+
+    return unless (defined($tmpdir));
+
+    rmtree($tmpdir) or warn(user_message(__x("Unable to remove temporary ".
+                                            "directory {dir}",
+                                            dir => $tmpdir)));
+    $tmpdir = undef;
+}
+
 package Sys::VirtV2V::Target::RHEV;
 
 use File::Temp qw(tempdir);
@@ -474,6 +518,17 @@ sub DESTROY
     # status.
     my $retval = $?;
 
+    eval {
+        my $nfs = Sys::VirtV2V::Target::RHEV::NFSHelper->new(sub {
+            Sys::VirtV2V::Target::RHEV::Vol->_cleanup();
+        });
+        $nfs->check_exit();
+    };
+    if ($@) {
+        warn($@);
+        $retval ||= 1;
+    }
+
     my $eh = Sys::VirtV2V::ExecHelper->run('umount', $self->{mountdir});
     if ($eh->status() != 0) {
         warn user_message(__x("Failed to unmount {path}. Command exited with ".
@@ -669,6 +724,8 @@ EOF
                                     dir => $dir,
                                     error => $!)));
 
+        return Sys::VirtV2V::Target::RHEV::Vol->_move_vols();
+
         my $vm;
         my $ovfpath = $dir.'/'.$vmuuid.'.ovf';
         open($vm, '>', $ovfpath)
-- 
1.7.0.1