From 4e1618ce72ef47d2e145ce853c917fc41df99afa Mon Sep 17 00:00:00 2001
From: Peter Krempa <pkrempa@redhat.com>
Date: Thu, 23 Feb 2017 18:13:02 +0100
Subject: [PATCH] qemu: domain: Add helper to generate indexed backing store
 names

The code is currently simple, but if we later add node names, it will be
necessary to generate the names based on the node name. Add a helper so
that there's a central point to fix once we add self-generated node
names.
---
 src/qemu/qemu_domain.c | 22 ++++++++++++++++++++++
 src/qemu/qemu_domain.h |  4 ++++
 2 files changed, 26 insertions(+)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 34f4d014ba..57b610c221 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -8558,3 +8558,25 @@ qemuDomainDiskLookupByNodename(virDomainDefPtr def,
 
     return NULL;
 }
+
+
+/**
+ * qemuDomainDiskBackingStoreGetName:
+ *
+ * Creates a name using the indexed syntax (vda[1])for the given backing store
+ * entry for a disk.
+ */
+char *
+qemuDomainDiskBackingStoreGetName(virDomainDiskDefPtr disk,
+                                  virStorageSourcePtr src ATTRIBUTE_UNUSED,
+                                  unsigned int idx)
+{
+    char *ret = NULL;
+
+    if (idx)
+        ignore_value(virAsprintf(&ret, "%s[%d]", disk->dst, idx));
+    else
+        ignore_value(VIR_STRDUP(ret, disk->dst));
+
+    return ret;
+}
diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index efdf393486..74d76a88cd 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -883,4 +883,8 @@ virDomainDiskDefPtr qemuDomainDiskLookupByNodename(virDomainDefPtr def,
                                                    virStorageSourcePtr *src,
                                                    unsigned int *idx);
 
+char *qemuDomainDiskBackingStoreGetName(virDomainDiskDefPtr disk,
+                                        virStorageSourcePtr src,
+                                        unsigned int idx);
+
 #endif /* __QEMU_DOMAIN_H__ */
-- 
2.47.2