Re: [QEMU][PATCH v2 07/11] hw/xen/xen-hvm-common: Use g_new and error_setg_errno

[Markus Armbruster <armbru@xxxxxxxxxx>]

Philippe Mathieu-Daudé <philmd@xxxxxxxxxx> writes:

> On 2/12/22 03:59, Vikram Garhwal wrote:
>> Replace g_malloc with g_new and perror with error_setg_errno.
>> 
>> Signed-off-by: Vikram Garhwal <vikram.garhwal@xxxxxxx>
>> ---
>>   hw/xen/xen-hvm-common.c | 15 ++++++++-------
>>   1 file changed, 8 insertions(+), 7 deletions(-)
>
>
>> @@ -717,7 +717,7 @@ void destroy_hvm_domain(bool reboot)
>>      xc_interface *xc_handle;
>>      int sts;
>>      int rc;
>> -
>> +    Error *errp = NULL;
>>      unsigned int reason = reboot ? SHUTDOWN_reboot : SHUTDOWN_poweroff;
>>   
>>      if (xen_dmod) {
>> @@ -726,7 +726,7 @@ void destroy_hvm_domain(bool reboot)
>>              return;
>>          }
>>          if (errno != ENOTTY /* old Xen */) {
>> -            perror("xendevicemodel_shutdown failed");
>> +            error_setg_errno(&errp, errno, "xendevicemodel_shutdown 
>> failed");
>
> See "qapi/error.h":
>
>   * = Passing errors around =
>   *
>   * Errors get passed to the caller through the conventional @errp
>   * parameter.
>
> Here you are not passing the error to the caller.

Instead, you're leaking its memory.

> Maybe you are looking for the "qemu/error-report.h" API?

Plausible.

Also, @errp is the conventional name for the Error ** parameter used to
pass errors to the caller.  Local Error * variables are usually called
@err or @local_err (I prefer the former).

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