[Libvir] Re: [PATCH] Fix pathological behaviour of "virsh help" (was: Re: RFC: replace "no support for hypervisor" error)

[Daniel Veillard]

On Wed, Jun 20, 2007 at 12:25:17PM +0100, Richard W.M. Jones wrote:
> Daniel Veillard wrote:
> >    - if our default behaviour was a bit less pathological
> >
> >   virsh: error: failed to connect to the hypervisor
> >   paphio:~/libvirt -> virsh help
> >   libvir: error : operation failed: xenProxyOpen
> >   virsh: error: failed to connect to the hypervisor
> 
> This patch fixes the pathological failure of 'virsh help command'.
> 
> (1) We allow ctl->conn to be NULL, meaning "no connection".
> 
> (2) All cmd* functions check vshConnectionUsability where required (I 
> checked this) except the ones which don't need to such as cmdHelp.
> 
> (3) vshInit has changed so that not being able to connect to a 
> hypervisor is a non-fatal condition.  Thus after vshInit, ctl->conn may 
> be NULL.
> 
> (4) I reordered the list of commands alphabetically, except that "help" 
> is listed first.
> 
> $ virsh help save
> libvir: error : operation failed: xenProxyOpen
> error: failed to connect to the hypervisor
>   NAME
>     save - save a domain state to a file
> 
>   SYNOPSIS
>     save <domain> <file>
> 
>   DESCRIPTION
>     Save a running domain.
> 
>   OPTIONS
>     <domain>         domain name, id or uuid
>     <file>           where to save the data
> 

  Hum, I wonder if help should not be special cased. I think it's okay
to not return immediately in the case where no command is given and
it's then possible to issue a new connect command from the shell.
So the patch looks fine to me, but we may refine this a bit too.

Daniel

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