Re: [Qemu-devel] [PATCH] terminal attributes is not restored when using /dev/tty monitor

["David S. Ahern" <daahern@cisco.com>]

On 02/20/2010 12:42 PM, Shahar Havivi wrote:
> On Sat, Feb 20, 2010 at 11:03:41AM -0600, Anthony Liguori wrote:
>> Date: Sat, 20 Feb 2010 11:03:41 -0600
>> From: Anthony Liguori <anthony@codemonkey.ws>
>> To: "David S. Ahern" <daahern@cisco.com>
>> Cc: Dor Laor <dlaor@redhat.com>, Shahar Havivi <shaharh@redhat.com>,
>> 	qemu-devel@nongnu.org
>> Subject: Re: [Qemu-devel] [PATCH] terminal attributes is not restored when
>> 	using /dev/tty monitor
>>
>> On 02/20/2010 09:18 AM, David S. Ahern wrote:
>>> On 02/20/2010 01:30 AM, Shahar Havivi wrote:
>>>> when exiting qemu that run with "-monitor /dev/tty", the launching
>>>> terminal get weird behaviour because no restore terminals action has
>>>> taken.
>>>> added chr_close and register atexit() code for tty devices (like stdio
>>>> does)
>>>>
>>>> Signed-off-by: Shahar Havivi<shaharh@redhat.com>
>>>> ---
>>>>  qemu-char.c |   14 ++++++++++++++
>>>>  1 files changed, 14 insertions(+), 0 deletions(-)
>>>>
>>>> diff --git a/qemu-char.c b/qemu-char.c
>>>> index 75dbf66..de16883 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 +1174,17 @@ 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(struct CharDriverState *chr)
>>>> +{
>>>> +    tty_exit();
>>>> +    fd_chr_close(chr);
>>>> +}
>>>
>>> The close callback needs to close the fd for the device as well. I have
>>> sent a patch to handle this; waiting for it to be included:
>>>
>>> http://permalink.gmane.org/gmane.comp.emulators.qemu/63472
>>
>> It didn't apply with git-am.  I'm not sure why, am investigating now.
>>
>> Regards,
>>
>> Anthony Liguori
>>
> Note that the method fd_chr_close() is closing the fd_in, no need to the
> close logic again, and when opening a monitor with /dev/tty the
> chr->chr_close not called that is why you need to register with
> atexit(). (same as stdio monitor does).
> Shahar.

I don't see that fd_chr_close() closes the fd; it only unregisters the
handler.

David