[PATCH] 230.4Kbps support for serial port
Thu Jan 9 21:45:00 GMT 2003
On Thu, Jan 09, 2003 at 11:18:31AM -0700, Troy Curtiss wrote:
> I see in the latest fhandler_serial::tcsetattr(), the following part of
>my patch wasn't applied. This piece is necessary in the event the serial
>device doesn't actually support 230.4Kbps (so tcsetattr() will return an
>error instead of simply not working.)
This piece short circuits lots of subsequent code, however. It's a departure
from the way this function used to work. And it does need to set an errno,
as you'd indicated. I don't know what the errno would be, though.
>@@ -723,8 +726,12 @@ fhandler_serial::tcsetattr (int action,
> state.fAbortOnError = TRUE;
> /* -------------- Set state and exit ------------------ */
>- if (memcmp (&ostate, &state, sizeof (state)) != 0)
>- SetCommState (get_handle (), &state);
>+ if ((memcmp (&ostate, &state, sizeof (state)) != 0) &&
>+ !SetCommState (get_handle (), &state))
>+ /* Return now if any of the parameters in the DCB didn't take */
>+ return -1;
>At 03:21 AM 1/9/2003 -0500, you wrote:
>>On Tue, Jan 07, 2003 at 03:48:51PM -0700, Troy Curtiss wrote:
>>> Attached is a patch that enables cygwin to talk at 230400 bps on serial
>>>ports that support the higher rate. It also does the necessary
>>>error-checking to confirm whether or not a given port is capable of
>>>extended bitrates. I added B230400 (for Posix) and CBR_230400 (for Win32)
>>>definitions to the appropriate header files (termios.h and winbase.h,
>>>respectively). I've been testing for a couple days now and it appears to
>>>work as designed. (We use a lot of extended bitrate devices at work,
>>>mostly with Win32 code - so this simply brings the paradigm across to the
>>>posix side of the house.)
>>>Question: Upon failure (ie. trying to configure a non-230.4K capable port
>>>to talk 230.4K), I simply return -1... I'm not sure whether POSIX would
>>>set errno = EINVAL or not... either way is fine.
>>> Let me know if you have any questions, otherwise it sure would be nice
>>>to roll this in if possible :) Thanks,
>>I'll apply this patch (with a reformatted changelog) to cygwin but not
>>to winbase.h. I couldn't find any reference to a CBR_230400 anywhere so
>>it wouldn't be technically correct to a windows header file.
>>>2003-01-06 Troy Curtiss <firstname.lastname@example.org>
>>> * fhandler_serial.cc (fhandler_serial::tcsetattr): Add support and
>>> capability checking for B230400 bitrate.
>>> * fhandler_serial.cc (fhandler_serial::tcgetattr): Add support for
>>> B230400 bitrate.
>>> * /cvs/src/src/winsup/w32api/include/winbase.h: Add CBR_230400
>>> definition for Win32 support of 230.4Kbps.
>>> * /cvs/src/src/winsup/cygwin/include/sys/termios.h: Add B230400
>>> definition for Posix support of 230.4Kbps.
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