Re: [Qemu-devel] [PATCH v4 06/11] savevm: add error parameter to qemu_savevm_state()

[Markus Armbruster]

Pavel Hrdina <phrd...@redhat.com> writes:

> Signed-off-by: Pavel Hrdina <phrd...@redhat.com>
> Reviewed-by: Eric Blake <ebl...@redhat.com>
> ---
>  savevm.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/savevm.c b/savevm.c
> index 7598934..3c1ac9e 100644
> --- a/savevm.c
> +++ b/savevm.c
> @@ -1910,7 +1910,7 @@ void qemu_savevm_state_cancel(void)
>      }
>  }
>  
> -static int qemu_savevm_state(QEMUFile *f)
> +static int qemu_savevm_state(QEMUFile *f, Error **errp)
>  {
>      int ret;
>      MigrationParams params = {
> @@ -1918,23 +1918,23 @@ static int qemu_savevm_state(QEMUFile *f)
>          .shared = 0
>      };
>  
> -    if (qemu_savevm_state_blocked(NULL)) {
> +    if (qemu_savevm_state_blocked(errp)) {
>          return -EINVAL;
>      }
>  
>      qemu_mutex_unlock_iothread();
> -    qemu_savevm_state_begin(f, &params, NULL);
> +    qemu_savevm_state_begin(f, &params, errp);
>      qemu_mutex_lock_iothread();
>  
>      while (qemu_file_get_error(f) == 0) {
> -        if (qemu_savevm_state_iterate(f, NULL) > 0) {
> +        if (qemu_savevm_state_iterate(f, errp) > 0) {
>              break;
>          }
>      }
>  
>      ret = qemu_file_get_error(f);
>      if (ret == 0) {
> -        qemu_savevm_state_complete(f, NULL);
> +        qemu_savevm_state_complete(f, errp);
>          ret = qemu_file_get_error(f);
>      }
>      if (ret != 0) {
> @@ -2321,7 +2321,7 @@ void do_savevm(Monitor *mon, const QDict *qdict)
>          monitor_printf(mon, "Could not open VM state file\n");
>          goto the_end;
>      }
> -    ret = qemu_savevm_state(f);
> +    ret = qemu_savevm_state(f, NULL);
>      vm_state_size = qemu_ftell(f);
>      qemu_fclose(f);
>      if (ret < 0) {
           monitor_printf(mon, "Error %d while writing VM\n", ret);
           goto the_end;
       }

First you go all the trouble to create detailed error reports deep down
in savevm.c, then you ignore them, and simply report (numeric!) errno
instead :)