Re: [PATCH 30/55] hyperv: use g_autoptr for WMI classes in hypervDomainGetVcpusFlags

[Laine Stump <laine@xxxxxxxxxx>]

On 1/21/21 1:51 PM, Matt Coleman wrote:
> Signed-off-by: Matt Coleman <matt@xxxxxxxxx>
> ---
>   src/hyperv/hyperv_driver.c | 30 ++++++++++--------------------
>   1 file changed, 10 insertions(+), 20 deletions(-)
>
> diff --git a/src/hyperv/hyperv_driver.c b/src/hyperv/hyperv_driver.c
> index f056761338..0642e42b35 100644
> --- a/src/hyperv/hyperv_driver.c
> +++ b/src/hyperv/hyperv_driver.c
> @@ -2023,12 +2023,11 @@ hypervDomainSetVcpus(virDomainPtr domain, unsigned int nvcpus)
>   static int
>   hypervDomainGetVcpusFlags(virDomainPtr domain, unsigned int flags)
>   {
> -    int result = -1;
>       char uuid_string[VIR_UUID_STRING_BUFLEN];
>       hypervPrivate *priv = domain->conn->privateData;
> -    Msvm_ComputerSystem *computerSystem = NULL;
> -    Msvm_ProcessorSettingData *proc_sd = NULL;
> -    Msvm_VirtualSystemSettingData *vssd = NULL;
> +    g_autoptr(Msvm_ComputerSystem) computerSystem = NULL;
> +    g_autoptr(Msvm_ProcessorSettingData) proc_sd = NULL;
> +    g_autoptr(Msvm_VirtualSystemSettingData) vssd = NULL;
>   
>       virCheckFlags(VIR_DOMAIN_VCPU_LIVE |
>                     VIR_DOMAIN_VCPU_CONFIG |
> @@ -2038,36 +2037,27 @@ hypervDomainGetVcpusFlags(virDomainPtr domain, unsigned int flags)
>   
>       /* Start by getting the Msvm_ComputerSystem */
>       if (hypervMsvmComputerSystemFromDomain(domain, &computerSystem) < 0)
> -        goto cleanup;
> +        return -1;
>   
>       /* Check @flags to see if we are to query a running domain, and fail
>        * if that domain is not running */
>       if (flags & VIR_DOMAIN_VCPU_LIVE &&
>           computerSystem->data->EnabledState != MSVM_COMPUTERSYSTEM_ENABLEDSTATE_ENABLED) {
>           virReportError(VIR_ERR_OPERATION_INVALID, "%s", _("Domain is not active"));
> -        goto cleanup;
> +        return -1;
>       }
>   
>       /* Check @flags to see if we are to return the maximum vCPU limit */
> -    if (flags & VIR_DOMAIN_VCPU_MAXIMUM) {
> -        result = hypervConnectGetMaxVcpus(domain->conn, NULL);
> -        goto cleanup;
> -    }
> +    if (flags & VIR_DOMAIN_VCPU_MAXIMUM)
> +        return hypervConnectGetMaxVcpus(domain->conn, NULL);
>   
>       if (hypervGetMsvmVirtualSystemSettingDataFromUUID(priv, uuid_string, &vssd) < 0)
> -        goto cleanup;
> +        return -1;
>   
>       if (hypervGetProcessorSD(priv, vssd->data->InstanceID, &proc_sd) < 0)
> -        goto cleanup;
> -
> -    result = proc_sd->data->VirtualQuantity;
> -
> - cleanup:
> -    hypervFreeObject((hypervObject *)computerSystem);
> -    hypervFreeObject((hypervObject *)vssd);
> -    hypervFreeObject((hypervObject *)proc_sd);
> +        return -1;
>   
> -    return result;
> +    return proc_sd->data->VirtualQuantity;


Again, returning a value that is coming out of an auto-freed object. 
(Each time I see it, I'm more convinced that it probably does the right 
thing...)