[Libvir] Re: RFC: replace "no support for hypervisor" error

Daniel Veillard wrote: The attached patch: (1) Makes VIR_ERR_NO_SUPPORT mean that a function is not supported by the hypervisor. It changes the message to be more specific and coincidentally corrects a bug which was causing the optional info field to be dropped. (2) Makes VIR_ERR_NO_CONNECT mean that we could not connect to the hypervisor. (3) Deprecates VIR_ERR_CALL_FAILED, because the meaning and use of this overlapped with VIR_ERR_NO_SUPPORT, and some calls failed with one and other calls failed with the other. Accordingly it changes all VIR_ERR_CALL_FAILED errors into VIR_ERR_NO_SUPPORT errors. (4) Removes all error messages which occur before VIR_DRV_OPEN_DECLINED. If a driver is declines a URI, then that is normal behaviour and no reason to print an error. A later driver in the chain may accept the URI, and if none of the drivers can accept it then libvirt.c:do_open contains code to generate an error. (5) If xen_unified.c was passed a naked string like "foo" as a URI then it would try to use it as a relative file reference. This was wrong and obscures a whole class of error message, so I've changed it so that xen_unified.c will only try to accept an absolute pathname (eg. ///var/lib/xen/xend-socket). Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903