Re: [Qemu-devel] [PATCH 4/4] HMP: Introduce console command

[Lei Li]

On 01/22/2013 03:52 AM, Anthony Liguori wrote:
> Why don't you resubmit the series without this patch.  I think this
> needs a bit of work...

Sure, I will resubmit the series without this patch and try to implement
this console command as your suggestion in another thread later.

Thanks for your time!

> Lei Li <address@hidden> writes:
>
> > Signed-off-by: Lei Li <address@hidden>
> > ---
> >   hmp-commands.hx           |   21 ++++++++++++++++++
> >   hmp.c                     |   52 +++++++++++++++++++++++++++++++++++++++++++++
> >   hmp.h                     |    1 +
> >   include/monitor/monitor.h |    3 ++
> >   monitor.c                 |   15 +++++++++++++
> >   5 files changed, 92 insertions(+), 0 deletions(-)
> >
> > diff --git a/hmp-commands.hx b/hmp-commands.hx
> > index 52ead10..7f7a54a 100644
> > --- a/hmp-commands.hx
> > +++ b/hmp-commands.hx
> > @@ -875,6 +875,27 @@ if the requested size is larger than it.
> >   ETEXI
> >   
> >       {
> > +        .name       = "console",
> > +        .args_type  = "chardev:s",
> > +        .params     = "chardev",
> > +        .mhandler.cmd = hmp_console,
> > +    },
> > +
> > +STEXI
> > address@hidden console @var{device}
> > address@hidden console
> > +Connect to the serial console from within the monitor, allow to write data
> > +to memchardev @var{chardev}. Exit from the console and return back to
> > +monitor by 'ctrl-]' or enter.
> > +
> > address@hidden
> > +(qemu) console foo
> > +foo: data string...
> > address@hidden example
> > +
> > +ETEXI
> > +
> > +    {
> >           .name       = "migrate",
> >           .args_type  = "detach:-d,blk:-b,inc:-i,uri:s",
> >           .params     = "[-d] [-b] [-i] uri",
> > diff --git a/hmp.c b/hmp.c
> > index 7e86c24..fab5090 100644
> > --- a/hmp.c
> > +++ b/hmp.c
> > @@ -1389,3 +1389,55 @@ void hmp_chardev_remove(Monitor *mon, const QDict *qdict)
> >       qmp_chardev_remove(qdict_get_str(qdict, "id"), &local_err);
> >       hmp_handle_error(mon, &local_err);
> >   }
> > +
> > +enum escape_char
> > +{
> > +    ESCAPE_CHAR_CTRL_GS = 0x1d  /* ctrl-] used for escape */
> > +};
> > +
> > +static void hmp_read_console(Monitor *mon, const char *data,
> > +                             void *opaque)
> > +{
> > +    CharDriverState *chr = opaque;
> > +    uint32_t size = strlen(data);
> > +    enum escape_char console_escape = ESCAPE_CHAR_CTRL_GS;
> > +
> > +    Error *err = NULL;
> > +
> > +    if (*data == console_escape) {
> > +        monitor_resume(mon);
> > +        return;
> > +    }
> > +
> > +    qmp_memchar_write(chr->label, size, data, 0, 0, &err);
> So how would the user see data that gets read from the console?

Yeah, I did not consider this.

> There should be a qmp_memchar_read() call somewhere, no?  I think we
> previously discussed doing this based on a timer callback...  It's a
> little hackish but it should work well enough in practice.

Okay, I need to think about this...

> Regards,
>
> Anthony Liguori
>
> > +
> > +    if (err) {
> > +        monitor_printf(mon, "%s\n", error_get_pretty(err));
> > +        monitor_read_command(mon,1);
> > +        error_free(err);
> > +        return;
> > +    }
> > +
> > +    monitor_read_command(mon, 1);
> > +}
> > +
> > +void hmp_console(Monitor *mon, const QDict *qdict)
> > +{
> > +    const char *device = qdict_get_str(qdict, "chardev");
> > +    CharDriverState *chr;
> > +    Error *err = NULL;
> > +
> > +    chr = qemu_chr_find(device);
> > +
> > +    if (!chr) {
> > +        error_set(&err, QERR_DEVICE_NOT_FOUND, device);
> > +        goto out;
> > +    }
> > +
> > +    if (monitor_read_console(mon, device, hmp_read_console, chr) < 0) {
> > +        monitor_printf(mon, "Connect to console %s failed\n", device);
> > +    }
> > +
> > +out:
> > +    hmp_handle_error(mon, &err);
> > +}
> > diff --git a/hmp.h b/hmp.h
> > index 076d8cf..a01268e 100644
> > --- a/hmp.h
> > +++ b/hmp.h
> > @@ -84,5 +84,6 @@ void hmp_nbd_server_add(Monitor *mon, const QDict *qdict);
> >   void hmp_nbd_server_stop(Monitor *mon, const QDict *qdict);
> >   void hmp_chardev_add(Monitor *mon, const QDict *qdict);
> >   void hmp_chardev_remove(Monitor *mon, const QDict *qdict);
> > +void hmp_console(Monitor *mon, const QDict *qdict);
> >   
> >   #endif
> > diff --git a/include/monitor/monitor.h b/include/monitor/monitor.h
> > index 87fb49c..a14e965 100644
> > --- a/include/monitor/monitor.h
> > +++ b/include/monitor/monitor.h
> > @@ -86,6 +86,9 @@ ReadLineState *monitor_get_rs(Monitor *mon);
> >   int monitor_read_password(Monitor *mon, ReadLineFunc *readline_func,
> >                             void *opaque);
> >   
> > +int monitor_read_console(Monitor *mon, const char *device,
> > +                         ReadLineFunc *readline_func, void *opaque);
> > +
> >   int qmp_qom_set(Monitor *mon, const QDict *qdict, QObject **ret);
> >   
> >   int qmp_qom_get(Monitor *mon, const QDict *qdict, QObject **ret);
> > diff --git a/monitor.c b/monitor.c
> > index 20bd19b..6f6155d 100644
> > --- a/monitor.c
> > +++ b/monitor.c
> > @@ -260,6 +260,21 @@ int monitor_read_password(Monitor *mon, ReadLineFunc 
> > *readline_func,
> >       }
> >   }
> >   
> > +int monitor_read_console(Monitor *mon, const char *device,
> > +                         ReadLineFunc *readline_func, void *opaque)
> > +{
> > +    char prompt[60];
> > +
> > +    if (!mon->rs) {
> > +        return -1;
> > +    }
> > +
> > +    snprintf(prompt, sizeof(prompt), "%s: ", device);
> > +    readline_start(mon->rs, prompt, 0, readline_func, opaque);
> > +
> > +    return 0;
> > +}
> > +
> >   void monitor_flush(Monitor *mon)
> >   {
> >       if (mon && mon->outbuf_index != 0 && !mon->mux_out) {
> > --
> > 1.7.7.6


--
Lei