[Qemu-devel] Re: [PATCH 2/3] Introduce do_snapshot_blkdev() and monitor command to handle it.

[Luiz Capitulino <lcapitulino@redhat.com>]

On Wed, 15 Dec 2010 17:57:25 +0100
Jes Sorensen <Jes.Sorensen@redhat.com> wrote:

> On 12/15/10 17:55, Kevin Wolf wrote:
> >> +int do_snapshot_blkdev(Monitor *mon, const QDict *qdict, QObject **ret_data)
> >> +{
> >> +    const char *device = qdict_get_str(qdict, "device");
> >> +    const char *filename = qdict_get_try_str(qdict, "snapshot_file");
> >> +    const char *format = qdict_get_try_str(qdict, "format");
> >> +    const char format_qcow2[] = "qcow2";
> >> +    BlockDriverState *bs;
> >> +    BlockDriver *drv, *proto_drv;
> >> +    int ret = 0;
> >> +    int flags;
> >> +
> >> +    bs = bdrv_find(device);
> >> +    if (!bs) {
> >> +        qerror_report(QERR_DEVICE_NOT_FOUND, device);
> >> +        ret = -1;
> >> +        goto out;
> >> +    }
> >> +
> >> +    if (!format) {
> >> +        format = format_qcow2;
> >> +    }
> >> +
> >> +    drv = bdrv_find_format(format);
> >> +    if (!drv) {
> >> +        qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
> >> +        ret = -1;
> >> +        goto out;
> >> +    }
> >> +
> >> +    proto_drv = bdrv_find_protocol(filename);
> >> +    if (!proto_drv) {
> >> +        qerror_report(QERR_INVALID_BLOCK_FORMAT, format);
> >> +        ret = -1;
> >> +        goto out;
> >> +    }
> >> +
> >> +    ret = bdrv_img_create(filename, format, bs->filename,
> >> +                          bs->drv->format_name, NULL, -1, bs->open_flags);
> >> +    if (ret) {
> >> +        goto out;
> >> +    }
> >> +
> >> +    qemu_aio_flush();
> >> +    bdrv_flush(bs);
> >> +
> >> +    flags = bs->open_flags;
> >> +    bdrv_close(bs);
> >> +    ret = bdrv_open(bs, filename, flags, drv);
> >> +    /*
> >> +     * If reopening the image file we just created fails, we really
> >> +     * are in trouble :(
> >> +     */
> >> +    assert(ret == 0);
> >> +out:
> >> +    if (ret) {
> >> +        ret = 1;
> > 
> > I seem to remember that errors are always -1 for monitor commands.
> 
> I mapped it after something else, but admitted I cannot remember where -
> can someone clarify?

-1

> 
> Cheers,
> Jes
>