API: Introduce field for reporting temporary disk space usage of a domain job

A pull mode backup job uses temporary disk images to hold the changed
parts of the disk while the client is copying the changes. Since usage
of the temporary space can be monitored but doesn't really fit any of
the existing stats fields introduce new fields for reporting this data.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

include/libvirt/libvirt-domain.h

@@ -3600,6 +3600,20 @@ typedef enum {
  */
 # define VIR_DOMAIN_JOB_SUCCESS "success"
 
+/**
+ * VIR_DOMAIN_JOB_DISK_TEMP_USED:
+ * virDomainGetJobStats field: current usage of temporary disk space for the
+ * job in bytes as VIR_TYPED_PARAM_ULLONG.
+ */
+# define VIR_DOMAIN_JOB_DISK_TEMP_USED "disk_temp_used"
+
+/**
+ * VIR_DOMAIN_JOB_DISK_TEMP_TOTAL:
+ * virDomainGetJobStats field: possible total temporary disk space for the
+ * job in bytes as VIR_TYPED_PARAM_ULLONG.
+ */
+# define VIR_DOMAIN_JOB_DISK_TEMP_TOTAL "disk_temp_total"
+
 /**
  * virConnectDomainEventGenericCallback:
  * @conn: the connection pointer