From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2155) id B59AE3876057; Thu, 26 Mar 2020 11:26:36 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B59AE3876057 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Corinna Vinschen To: cygwin-cvs@sourceware.org Subject: [newlib-cygwin] Cygwin: serial: tcsetattr: set timeouts unconditionally X-Act-Checkin: newlib-cygwin X-Git-Author: Corinna Vinschen X-Git-Refname: refs/heads/master X-Git-Oldrev: 72294cd21175c307a6552416b249fc8d66ee0bbc X-Git-Newrev: 912c90261559914d931f0764f836217d939b1112 Message-Id: <20200326112636.B59AE3876057@sourceware.org> Date: Thu, 26 Mar 2020 11:26:36 +0000 (GMT) X-BeenThere: cygwin-cvs@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component git logs List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 26 Mar 2020 11:26:36 -0000 https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=912c90261559914d931f0764f836217d939b1112 commit 912c90261559914d931f0764f836217d939b1112 Author: Corinna Vinschen Date: Mon Mar 23 12:13:35 2020 +0100 Cygwin: serial: tcsetattr: set timeouts unconditionally tcsetattr checks if the VTIME and VMIN values changed and only calls SetCommTimeouts if so. That's a problem if tcsetattr is supposed to set VTIME and VIMN to 0, because these are the start values anyway. But this requires to set ReadIntervalTimeout to MAXDWORD, which just doesn't happen. Fix this by dropping the over-optimization of checking the old values before calling SetCommTimeouts, Signed-off-by: Corinna Vinschen Diff: --- winsup/cygwin/fhandler_serial.cc | 79 +++++++++++++++++++--------------------- 1 file changed, 38 insertions(+), 41 deletions(-) diff --git a/winsup/cygwin/fhandler_serial.cc b/winsup/cygwin/fhandler_serial.cc index 66e80197b..c7c412e57 100644 --- a/winsup/cygwin/fhandler_serial.cc +++ b/winsup/cygwin/fhandler_serial.cc @@ -600,7 +600,6 @@ fhandler_serial::tcsetattr (int action, const struct termios *t) bool dropDTR = false; COMMTIMEOUTS to; DCB ostate, state; - cc_t ovtime = vtime_, ovmin = vmin_; int tmpDtr, tmpRts, res; res = tmpDtr = tmpRts = 0; @@ -909,49 +908,47 @@ fhandler_serial::tcsetattr (int action, const struct termios *t) debug_printf ("vtime %u, vmin %u", vtime_, vmin_); - if (ovmin != vmin_ || ovtime != vtime_) - { - memset (&to, 0, sizeof (to)); + memset (&to, 0, sizeof (to)); - if ((vmin_ > 0) && (vtime_ == 0)) - { - /* Returns immediately with whatever is in buffer on a ReadFile(); - or blocks if nothing found. We will keep calling ReadFile(); until - vmin_ characters are read */ - to.ReadIntervalTimeout = to.ReadTotalTimeoutMultiplier = MAXDWORD; - to.ReadTotalTimeoutConstant = MAXDWORD - 1; - } - else if ((vmin_ == 0) && (vtime_ > 0)) - { - /* set timeoout constant appropriately and we will only try to - read one character in ReadFile() */ - to.ReadTotalTimeoutConstant = vtime_ * 100; - to.ReadIntervalTimeout = to.ReadTotalTimeoutMultiplier = MAXDWORD; - } - else if ((vmin_ > 0) && (vtime_ > 0)) - { - /* time applies to the interval time for this case */ - to.ReadIntervalTimeout = vtime_ * 100; - } - else if ((vmin_ == 0) && (vtime_ == 0)) - { - /* returns immediately with whatever is in buffer as per - Time-Outs docs in Win32 SDK API docs */ - to.ReadIntervalTimeout = MAXDWORD; - } + if ((vmin_ > 0) && (vtime_ == 0)) + { + /* Returns immediately with whatever is in buffer on a ReadFile(); + or blocks if nothing found. We will keep calling ReadFile(); until + vmin_ characters are read */ + to.ReadIntervalTimeout = to.ReadTotalTimeoutMultiplier = MAXDWORD; + to.ReadTotalTimeoutConstant = MAXDWORD - 1; + } + else if ((vmin_ == 0) && (vtime_ > 0)) + { + /* set timeoout constant appropriately and we will only try to + read one character in ReadFile() */ + to.ReadTotalTimeoutConstant = vtime_ * 100; + to.ReadIntervalTimeout = to.ReadTotalTimeoutMultiplier = MAXDWORD; + } + else if ((vmin_ > 0) && (vtime_ > 0)) + { + /* time applies to the interval time for this case */ + to.ReadIntervalTimeout = vtime_ * 100; + } + else if ((vmin_ == 0) && (vtime_ == 0)) + { + /* returns immediately with whatever is in buffer as per + Time-Outs docs in Win32 SDK API docs */ + to.ReadIntervalTimeout = MAXDWORD; + } - debug_printf ("ReadTotalTimeoutConstant %u, ReadIntervalTimeout %u, ReadTotalTimeoutMultiplier %u", - to.ReadTotalTimeoutConstant, to.ReadIntervalTimeout, to.ReadTotalTimeoutMultiplier); + debug_printf ("ReadTotalTimeoutConstant %u, ReadIntervalTimeout %u, " + "ReadTotalTimeoutMultiplier %u", to.ReadTotalTimeoutConstant, + to.ReadIntervalTimeout, to.ReadTotalTimeoutMultiplier); - if (!SetCommTimeouts(get_handle (), &to)) - { - /* SetCommTimeouts() failed. Keep track of this so we - can set errno to EINVAL later and return failure */ - termios_printf ("SetCommTimeouts() failed, %E"); - __seterrno (); - res = -1; - } - } + if (!SetCommTimeouts(get_handle (), &to)) + { + /* SetCommTimeouts() failed. Keep track of this so we + can set errno to EINVAL later and return failure */ + termios_printf ("SetCommTimeouts() failed, %E"); + __seterrno (); + res = -1; + } return res; }