4a051b807e
For guests backed by gluster volumes (or other network storage) we don't fill the backing chain (see qemuDomainDetermineDiskChain). This leaves the "relPath" field of the top image NULL. This causes a crash in virStorageFileChainLookup() when looking up a backing element for such a disk. Since I'm working on adding support for network storage and one of the steps will make the "relPath" field optional let's use STREQ_NULLABLE instead of STREQ in virStorageFileChainLookup() to avoid the problem.
LibVirt : simple API for virtualization Libvirt is a C toolkit to interact with the virtualization capabilities of recent versions of Linux (and other OSes). It is free software available under the GNU Lesser General Public License. Virtualization of the Linux Operating System means the ability to run multiple instances of Operating Systems concurrently on a single hardware system where the basic resources are driven by a Linux instance. The library aim at providing long term stable C API initially for the Xen paravirtualization but should be able to integrate other virtualization mechanisms if needed. Daniel Veillard <veillard@redhat.com>