[libvirt] [PATCH 1/2] qemuDomainAttachNetDevice: Don't overwrite error on rollback

[Michal Privoznik]

If there is an error hotpluging a net device (for whatever
reason) a rollback operation is performed. However, whilst doing
so various helper functions that are called report errors on
their own. This results in the original error to be overwritten
and thus misleading the user.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_hotplug.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index e06862c..34f2135 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -935,6 +935,7 @@ qemuDomainAttachNetDevice(virQEMUDriverPtr driver,
                           virDomainNetDefPtr net)
 {
     qemuDomainObjPrivatePtr priv = vm->privateData;
+    virErrorPtr originalError = NULL;
     char **tapfdName = NULL;
     int *tapfd = NULL;
     size_t tapfdSize = 0;
@@ -1320,6 +1321,7 @@ qemuDomainAttachNetDevice(virQEMUDriverPtr driver,
     if (!virDomainObjIsActive(vm))
         goto cleanup;
 
+    originalError = virSaveLastError();
     if (vlan < 0) {
         if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_NETDEV)) {
             char *netdev_name;
@@ -1350,6 +1352,8 @@ qemuDomainAttachNetDevice(virQEMUDriverPtr driver,
         ignore_value(qemuDomainObjExitMonitor(driver, vm));
         VIR_FREE(hostnet_name);
     }
+    virSetError(originalError);
+    virFreeError(originalError);
     goto cleanup;
 }
 
-- 
2.8.4