[libvirt PATCH v2] qemu: fix domain start with corrupted save file

[Peter Krempa]

On Wed, Apr 22, 2020 at 15:15:31 +0200, Pavel Mores wrote:
> This is to fix
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=1791522
> 
> With this change, if a domain comes across a corrupted save file during
> boot it removes the save file and logs a warning but continues to boot
> normally instead of failing to boot (with a subsequent boot attempt
> succeeding).
> 
> The regression was introduced by 21ad56e932 and this change effectively
> reverts the relevant part of that commit.
> ---
>  src/qemu/qemu_driver.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index e8d47a41cd..2579ef3984 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -6810,13 +6810,14 @@ qemuDomainSaveImageOpen(virQEMUDriverPtr driver,
>      *ret_def = def;
>      *ret_data = data;
>  
> + cleanup:
>      return fd;
>  
>   error:
>      virDomainDefFree(def);
>      virQEMUSaveDataFree(data);
>      VIR_FORCE_CLOSE(fd);
> -    return -1;
> +    goto cleanup;

As pointed out previously this doesn't really help to make it more
obvious that 'fd' is abused to cary the other return codes here as well.

I prefer the following fix:

https://www.redhat.com/archives/libvir-list/2020-April/msg01101.html

along with some cleanups which IMO make the function more obvious.
Specifically the non-standard return values.