Re: [Qemu-devel] [PATCH] Restore terminal attributes for tty based monitor

[Shahar Havivi <shaharh@redhat.com>]

On Sat, Feb 27, 2010 at 09:20:28AM -0700, David S. Ahern wrote:
> Date: Sat, 27 Feb 2010 09:20:28 -0700
> From: "David S. Ahern" <daahern@cisco.com>
> To: Shahar Havivi <shaharh@redhat.com>
> CC: qemu-devel@nongnu.org, Dor Laor <dlaor@redhat.com>
> Subject: Re: [Qemu-devel] [PATCH] Restore terminal attributes for tty based
>  monitor
> 
> 
> 
> 
> 
> On 02/27/2010 01:41 AM, Shahar Havivi wrote:
> > On Fri, Feb 26, 2010 at 03:19:19PM -0700, David S. Ahern wrote:
> >> Date: Fri, 26 Feb 2010 15:19:19 -0700
> >> From: "David S. Ahern" <daahern@cisco.com>
> >> To: Shahar Havivi <shaharh@redhat.com>
> >> CC: qemu-devel@nongnu.org, Dor Laor <dlaor@redhat.com>
> >> Subject: Re: [Qemu-devel] [PATCH] Restore terminal attributes for tty based
> >>  monitor
> >>
> >>
> >>
> >>
> >>
> >> On 02/26/2010 01:04 PM, Shahar Havivi wrote:
> >>> Fix codding style
> >>> ---
> >>>  qemu-char.c |    9 +++++++++
> >>>  1 files changed, 9 insertions(+), 0 deletions(-)
> >>>
> >>> diff --git a/qemu-char.c b/qemu-char.c
> >>> index 4169492..4533887 100644
> >>> --- a/qemu-char.c
> >>> +++ b/qemu-char.c
> >>> @@ -1002,6 +1002,7 @@ static void tty_serial_init(int fd, int speed,
> >>>             speed, parity, data_bits, stop_bits);
> >>>  #endif
> >>>      tcgetattr (fd, &tty);
> >>> +    oldtty = tty;
> >>>
> >>>  #define check_speed(val) if (speed <= val) { spd = B##val; break; }
> >>>      speed = speed * 10 / 11;
> >>> @@ -1173,6 +1174,11 @@ static int tty_serial_ioctl(CharDriverState *chr, int cmd, void *arg)
> >>>      return 0;
> >>>  }
> >>>
> >>> +static void tty_exit(void)
> >>> +{
> >>> +    tcsetattr(0, TCSANOW, &oldtty);
> >>> +}
> >>> +
> >>>  static void qemu_chr_close_tty(CharDriverState *chr)
> >>>  {
> >>>      FDCharDriver *s = chr->opaque;
> >>> @@ -1207,6 +1213,9 @@ static CharDriverState *qemu_chr_open_tty(QemuOpts *opts)
> >>>      }
> >>>      chr->chr_ioctl = tty_serial_ioctl;
> >>>      chr->chr_close = qemu_chr_close_tty;
> >>> +    if (!term_atexit_done++) {
> >>> +        atexit(tty_exit);
> >>> +    }
> >>>      return chr;
> >>>  }
> >>>  #else  /* ! __linux__ && ! __sun__ */
> >>> --
> >>> 1.6.3.3
> >>>
> >>
> >> If qemu is invoked with both stdio and one or more host tty's only the
> >> last one referenced is reset one exit. Also, shouldn't the attributes be
> >> reset when the device is closed as opposed to exit? ie., a device
> >> connected to a tty chardev is removed via the monitor.
> >>
> >> David
> > stdio have the same handling code:
> > http://git.savannah.gnu.org/cgit/qemu.git/tree/qemu-char.c#n738
> > 
> > Shahar
> 
> Right now stdio is the only user of the oldtty global, so it holds the
> atributes for stdio. If you reuse the variable you are setting the tty
> (ttyN or ttySN) to the attributes retrieved from stdin - assuming it was
> even used.
> 
> I think you want to save the attributes for the terminal that is in use
> and reset that terminal on close / exit.
The oldtty global can be reuse, as far for the ttnN and ttySN you right,
it may be wrong for them, I will recheck.
Shahar.
> 
> David