[pve-devel] [PATCH container v2 1/2] restore: clean up config when invalid source archive is given

[Daniel Tschlatscher <d.tschlatscher@proxmox.com>]

Before, if a non-existent source archive parameter was passed when
restoring a container, the task would fail but leave an empty config
file behind. The same with invalid mount point configurations.
In both cases, the empty config will now be removed.

Signed-off-by: Daniel Tschlatscher <d.tschlatscher@proxmox.com>
---
Changes from v1:
* According to Thomas' suggestion I revised the code so that all
  errors are now handled centrally in the lower clean up handler which
  before was only used for the case when the config was unrecoverable
  and merged the two consecutive eval blocks into one.
  For this, I repurposed the $remove_lock variable and renamed it to
  better reflect its new usage.

 src/PVE/API2/LXC.pm | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/src/PVE/API2/LXC.pm b/src/PVE/API2/LXC.pm
index 03d7ea0..f2113de 100644
--- a/src/PVE/API2/LXC.pm
+++ b/src/PVE/API2/LXC.pm
@@ -372,12 +372,13 @@ __PACKAGE__->register_method({
 	eval { PVE::LXC::Config->create_and_lock_config($vmid, $force) };
 	die "$emsg $@" if $@;
 
-	my $remove_lock = 1;
+	my $destroy_config_on_error = !$same_container_exists;
 
 	my $code = sub {
 	    my $old_conf = PVE::LXC::Config->load_config($vmid);
 	    my $was_template;
 
+	    my $vollist = [];
 	    eval {
 		my $orig_mp_param; # only used if $restore
 		if ($restore) {
@@ -444,14 +445,10 @@ __PACKAGE__->register_method({
 			$mp_param->{rootfs} = "$storage:4"; # defaults to 4GB
 		    }
 		}
-	    };
-	    die "$emsg $@" if $@;
 
-	    # up until here we did not modify the container, besides the lock
-	    $remove_lock = 0;
+		# up until here we did not modify the container, besides the lock
+		$destroy_config_on_error = 1;
 
-	    my $vollist = [];
-	    eval {
 		$vollist = PVE::LXC::create_disks($storage_cfg, $vmid, $mp_param, $conf);
 
 		# we always have the 'create' lock so check for more than 1 entry
@@ -499,8 +496,10 @@ __PACKAGE__->register_method({
 	    };
 	    if (my $err = $@) {
 		PVE::LXC::destroy_disks($storage_cfg, $vollist);
-		eval { PVE::LXC::Config->destroy_config($vmid) };
-		warn $@ if $@;
+		if ($destroy_config_on_error) {
+		    eval { PVE::LXC::Config->destroy_config($vmid) };
+		    warn $@ if $@;
+		}
 		die "$emsg $err";
 	    }
 	    PVE::AccessControl::add_vm_to_pool($vmid, $pool) if $pool;
@@ -516,7 +515,7 @@ __PACKAGE__->register_method({
 	    };
 	    if (my $err = $@) {
 		# if we aborted before changing the container, we must remove the create lock
-		if ($remove_lock) {
+		if (!$destroy_config_on_error) {
 		    PVE::LXC::Config->remove_lock($vmid, 'create');
 		}
 		die $err;
-- 
2.30.2