[libvirt] [PATCH 3/7] qemu: Alter error path cleanup for qemuDomainAttachSCSIDisk

[John Ferlan]

Based on recent review comment - rather than have a spate of goto failxxxx,
change to a boolean based model. Ensures that the original error can be
preserved and cleanup is a bit more orderly if more objects are added.

Signed-off-by: John Ferlan <jferlan at redhat.com>
---
 src/qemu/qemu_hotplug.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index ce1db3c..0fc0084 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -544,8 +544,10 @@ qemuDomainAttachSCSIDisk(virConnectPtr conn,
 {
     size_t i;
     qemuDomainObjPrivatePtr priv = vm->privateData;
+    virErrorPtr orig_err;
     char *drivestr = NULL;
     char *devstr = NULL;
+    bool cleanupAddDrive = false;
     int ret = -1;
     virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
 
@@ -587,17 +589,17 @@ qemuDomainAttachSCSIDisk(virConnectPtr conn,
     if (VIR_REALLOC_N(vm->def->disks, vm->def->ndisks+1) < 0)
         goto error;
 
-    /* Attach the device - 2 step process */
     qemuDomainObjEnterMonitor(driver, vm);
 
     if (qemuMonitorAddDrive(priv->mon, drivestr) < 0)
-        goto failadddrive;
+        goto monitor_error;
+    cleanupAddDrive = true;
 
     if (qemuMonitorAddDevice(priv->mon, devstr) < 0)
-        goto failadddevice;
+        goto monitor_error;
 
     if (qemuDomainObjExitMonitor(driver, vm) < 0)
-        goto failexitmonitor;
+        goto error;
 
     virDomainAuditDisk(vm, NULL, disk->src, "attach", true);
 
@@ -611,14 +613,18 @@ qemuDomainAttachSCSIDisk(virConnectPtr conn,
     virObjectUnref(cfg);
     return ret;
 
- failadddevice:
+ monitor_error:
+    orig_err = virSaveLastError();
     /* XXX should call 'drive_del' on error but this does not exist yet */
-    VIR_WARN("qemuMonitorAddDevice failed on %s (%s)", drivestr, devstr);
+    if (cleanupAddDrive)
+        VIR_WARN("qemuMonitorAddDevice failed on %s (%s)", drivestr, devstr);
 
- failadddrive:
     ignore_value(qemuDomainObjExitMonitor(driver, vm));
+    if (orig_err) {
+        virSetError(orig_err);
+        virFreeError(orig_err);
+    }
 
- failexitmonitor:
     virDomainAuditDisk(vm, NULL, disk->src, "attach", false);
 
  error:
-- 
2.5.5