[libvirt PATCH 03/10] qemu: save/restore original error when recovering from failed bridge attach

[Laine Stump]

Not only was the original error code destroyed in the case of
encountering an error during recovery from a failed attach to the
bridge (and then *that* error was destroyed by logging a *second*
error about the failure to recover - virNetDevBridgeAddPort() already
logs an error, so the one about failing to recover was redundant), but
if the recovery was successful, the function would then return success
to the caller even though it had failed.

Signed-off-by: Laine Stump <laine at redhat.com>
---
 src/qemu/qemu_hotplug.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index c840889968..6395826c69 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -3352,14 +3352,13 @@ qemuDomainChangeNetBridge(virDomainObjPtr vm,
     ret = virNetDevBridgeAddPort(newbridge, olddev->ifname);
     virDomainAuditNet(vm, NULL, newdev, "attach", ret == 0);
     if (ret < 0) {
+        virErrorPtr err;
+
+        virErrorPreserveLast(&err);
         ret = virNetDevBridgeAddPort(oldbridge, olddev->ifname);
         virDomainAuditNet(vm, NULL, olddev, "attach", ret == 0);
-        if (ret < 0) {
-            virReportError(VIR_ERR_OPERATION_FAILED,
-                           _("unable to recover former state by adding port "
-                             "to bridge %s"), oldbridge);
-        }
-        return ret;
+        virErrorRestore(&err);
+        return -1;
     }
     /* caller will replace entire olddev with newdev in domain nets list */
     return 0;
-- 
2.24.1