Re: [Libvir] PATCH: Allow emptry bootloader

Latest XenD allows for default bootloader to be used if one is not defined for a paravirt OS. libvirt doesn't currently cope with this (see Solaris thread), since it requires either a bootloader or kernel to always be present. The attached patch allows for an emptry bootloader element to indicate that the domain should use the default. <domain type='xen' id='-1'> <name>rhel5pv</name> <uuid>614d7eb0-c6b1-5235-ac39-361b20f6cd49</uuid> <bootloader/> <os> <type>linux</type> </os> ...snip... </domain> The current API for looking up nodes in the SEXPR did not allow for the scenario where you might want to lookup a node with no content, eg (bootloader ) This distinction is needed here, so I added an sexpr_has() method to check for this. Second, it fixes a long standing bug where we'd record an error about the missing kernel or bootloader, but then continue generating (malformed) XML anyway. With this patch, it will correctly fail if the empty bootloader field is missing from the SEXPR.