[libvirt] [PATCH v4 3/5] qemu_driver: use g_autofree when possible

[Michal Privoznik]

On 10/16/19 10:54 PM, Daniel Henrique Barboza wrote:
> String and other scalar pointers an be auto-unref, sparing us
> a VIR_FREE() call.
> 
> This patch uses g_autofree whenever possible with strings and
> other scalar pointer types.
> 
> Suggested-by: Erik Skultety <eskultet at redhat.com>
> Signed-off-by: Daniel Henrique Barboza <danielhb413 at gmail.com>
> ---
>   src/qemu/qemu_driver.c | 203 ++++++++++++++---------------------------
>   1 file changed, 68 insertions(+), 135 deletions(-)
> 


> @@ -3300,7 +3295,7 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver,
>                          int compressed, const char *compressedpath,
>                          const char *xmlin, unsigned int flags)
>   {
> -    char *xml = NULL;
> +    g_autofree char *xml = NULL;
>       bool was_running = false;
>       int ret = -1;
>       virObjectEventPtr event = NULL;
> @@ -3381,7 +3376,6 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver,
>       if (!(data = virQEMUSaveDataNew(xml, cookie, was_running, compressed,
>                                       driver->xmlopt)))
>           goto endjob;
> -    xml = NULL;

No, this line has to be here. The point is that virQEMUSaveDataNew() 
takes ownership of @xml (in a very clumsy way though), so 
qemuDomainSaveInternal() has to refrain from freeing it. Setting it to 
NULL is how we achieve that.

>   
>       ret = qemuDomainSaveMemory(driver, vm, path, data, compressedpath,
>                                  flags, QEMU_ASYNC_JOB_SAVE);

Michal