Re: [libvirt RFCv7 12/40] tools: make use of params in doSave

[Claudio Fontana]

On 5/6/22 3:24 PM, Daniel P. Berrangé wrote:
> On Fri, May 06, 2022 at 03:19:31PM +0200, Claudio Fontana wrote:
>> whops this is pretty wrong.
>>
>> On 5/6/22 3:10 PM, Claudio Fontana wrote:
>>> Signed-off-by: Claudio Fontana <cfont...@suse.de>
>>> ---
>>>  tools/virsh-domain.c | 25 ++++++++++++++++++-------
>>>  1 file changed, 18 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
>>> index ba492e807e..be5679df0f 100644
>>> --- a/tools/virsh-domain.c
>>> +++ b/tools/virsh-domain.c
>>> @@ -4203,6 +4203,9 @@ doSave(void *opaque)
>>>      g_autoptr(virshDomain) dom = NULL;
>>>      const char *name = NULL;
>>>      const char *to = NULL;
>>> +    virTypedParameterPtr params = NULL;
>>> +    int nparams = 0;
>>> +    int maxparams = 0;
>>>      unsigned int flags = 0;
>>>      const char *xmlfile = NULL;
>>>      g_autofree char *xml = NULL;
>>> @@ -4216,9 +4219,13 @@ doSave(void *opaque)
>>>          goto out_sig;
>>>  #endif /* !WIN32 */
>>>  
>>> -    if (vshCommandOptStringReq(ctl, cmd, "file", &to) < 0)
>>> +    if (vshCommandOptStringReq(ctl, cmd, "file", &to) < 0) {
>>>          goto out;
>>> -
>>> +    } else {
>>> +        if (virTypedParamsAddString(&params, &nparams, &maxparams,
>>> +                                    VIR_SAVE_PARAM_FILE, to) < 0)
>>> +            goto out;
>>> +    }
>>>      if (vshCommandOptBool(cmd, "bypass-cache"))
>>>          flags |= VIR_DOMAIN_SAVE_BYPASS_CACHE;
>>>      if (vshCommandOptBool(cmd, "running"))
>>> @@ -4232,14 +4239,17 @@ doSave(void *opaque)
>>>      if (!(dom = virshCommandOptDomain(ctl, cmd, &name)))
>>>          goto out;
>>>  
>>> -    if (xmlfile &&
>>> -        virFileReadAll(xmlfile, VSH_MAX_XML_FILE, &xml) < 0) {
>>> -        vshReportError(ctl);
>>> -        goto out;
>>> +    if (xmlfile) {
>>> +        if (virFileReadAll(xmlfile, VSH_MAX_XML_FILE, &xml) < 0) {
>>> +            vshReportError(ctl);
>>> +            goto out;
>>> +        } else if (virTypedParamsAddString(&params, &nparams, &maxparams,
>>> +                                           VIR_SAVE_PARAM_DXML, xml) < 0)
>>> +            goto out;
>>>      }
>>>  
>>>      if (flags || xml) {
>>> -        rc = virDomainSaveFlags(dom, to, xml, flags);
>>> +        rc = virDomainSaveParams(dom, params, nparams, flags);
>>>      } else {
>>>          rc = virDomainSave(dom, to);
>>
>> Could you help me understand what is the right check to use here?
>>
>> Should I do like before,
>>
>> if (flags || xml) {
>>  rc = virDomainSaveFlags(dom, to, xml, flags);
>> } else {
>>  rc = virDomainSave(dom, to);
>> }
>>
>> and only involve virDomainSaveParams when introduced later?
>>
>> How should we decide whether to trigger virDomainSaveFlags
>> or virDomainSaveParams ...?
> 
> virsh should always use the oldest API possible to achieve the
> task. IOW, only invoke virDomainSaveParams for a command line
> argument requires use of a parameter that the old API doesn't
> support.
> 
> With regards,
> Daniel
> 

Very helpful, thanks.

Claudio