Re: [Qemu-devel] [PATCH 1/2] qga: add guest-get-time command

[Lei Li]

On 03/02/2013 01:02 AM, Eric Blake wrote:
> On 03/01/2013 02:32 AM, Lei Li wrote:
> > Signed-off-by: Lei Li <address@hidden>
> > ---
> >   qga/commands-posix.c | 16 ++++++++++++++++
> >   qga/qapi-schema.json | 16 ++++++++++++++++
> >   2 files changed, 32 insertions(+)
> >
> > diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> > index 0ad73f3..f159e25 100644
> > --- a/qga/commands-posix.c
> > +++ b/qga/commands-posix.c
> > @@ -119,6 +119,22 @@ void qmp_guest_shutdown(bool has_mode, const char *mode, 
> > Error **err)
> >       /* succeded */
> >   }
> >   
> > +int64_t qmp_guest_get_time(Error **errp)
> > +{
> > +   int ret;
> > +   qemu_timeval tq;
> > +   int64_t time_ns;
> > +
> > +   ret = qemu_gettimeofday(&tq);
> > +   if (ret < 0) {
> > +       error_setg_errno(errp, errno, "Failed to get time");
> > +       return -1;
> > +   }
> > +
> > +   time_ns = tq.tv_sec * 1000000000LL + tq.tv_usec * 1000;
> Is it worth a sanity check that the tv_sec scaling doesn't overflow?  Of
> course, that won't happen until far into the future (well beyond the
> 2038 overflow of 32-bit seconds since Epoch), so it won't hit in OUR
> lifetime, so I can look the other way.
> >   
> >   ##
> > +# @guest-get-time:
> > +#
> > +# Get the information about guest time relative to the Epoch
> > +# of 1970-01-01 in UTC/GMT.
> UTC and GMT are not the same thing.  I'd drop the '/GMT'.
> http://www.diffen.com/difference/GMT_vs_UTC

Oh, good to know! :)
Thanks.

> > +#
> > +# This command try to get the guest's notion of the current
> > +# time.
> This sentence is redundant with the first one, and has grammar issues.
> Drop it.

Sure.

> > +#
> > +# Returns: Time in nanoseconds on success.
> > +#
> > +# Since 1.5
> > +##
> > +{ 'command': 'guest-get-time',
> > +  'returns': 'int' }
> > +
> > +##
> >   # @GuestAgentCommandInfo:
> >   #
> >   # Information about guest agent commands.


--
Lei