Package: ncurses-bin
Version: 6.3+20220423-2
Followup-For: Bug #60377
Control: tags -1 patch
Control: tags -1 patch
Dear Maintainer,
This is still a problem. It causes my VT340 serial terminal to hang,
but not immediately. It happens the next time a program tries to open
/dev/ttyUSB0, for example, getty after logging out. I presume this
hasn't been fixed because the bug only affects hardware terminals that
lack a carrier detect line (such as any DEC terminal connected via
DEC423 MMJ).
If anything, clocal ought to be asserted by default, not disabled.
However, I suggest that `reset` should do neither. The man page for
reset is clear on what it does and it does not mention clocal. I have
attached a patch which brings the program back into line with its
documentation.
Thank you,
--Ben
-- System Information:
Debian Release: bookworm/sid
APT prefers testing
APT policy: (500, 'testing')
Architecture: amd64 (x86_64)
Kernel: Linux 6.0.0-4-amd64 (SMP w/8 CPU threads; PREEMPT)
Kernel taint flags: TAINT_SOFTLOCKUP
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled
Versions of packages ncurses-bin depends on:
ii libc6 2.36-6
ii libtinfo6 6.3+20220423-2
ncurses-bin recommends no packages.
ncurses-bin suggests no packages.
-- no debconf information
--- reset_cmd.c.orig 2021-10-02 11:08:44.000000000 -0700
+++ reset_cmd.c 2022-11-22 16:00:29.005361817 -0800
@@ -190,13 +190,14 @@
/*
* Reset the terminal mode bits to a sensible state. Very useful after
- * a child program dies in raw mode.
+ * a child program dies in raw mode. Requires termios(3) to work.
*/
void
reset_tty_settings(int fd, TTY * tty_settings, int noset)
{
GET_TTY(fd, tty_settings);
+ /* First reset any special characters to their default values */
#ifdef TERMIOS
#if defined(VDISCARD) && defined(CDISCARD)
reset_char(VDISCARD, CDISCARD);
@@ -228,94 +229,38 @@
reset_char(VWERASE, CWERASE);
#endif
- tty_settings->c_iflag &= ~((unsigned) (IGNBRK
- | PARMRK
- | INPCK
- | ISTRIP
- | INLCR
- | IGNCR
-#ifdef IUCLC
- | IUCLC
-#endif
-#ifdef IXANY
- | IXANY
-#endif
- | IXOFF));
+ /* Next, the reset command does the following
+ *
+ * sets cooked and echo modes,
+ * turns off cbreak and raw modes and
+ * turns on newline translation on output.
+ *
+ * It does not mess with other settings, such as IXOFF and CLOCAL,
+ * as the correct values depend upon what type of terminal (and
+ * even what type of serial cable) is being used.
+ *
+ * Users who need a blunter instrument can try `stty sane` which
+ * makes presumptions about a "typical" setup.
+ */
+
+ /* "Cooked" means: brkint ignpar istrip icrnl ixon opost isig icanon */
+ /* Setting cooked automatically turns off "raw" and "cbreak" */
tty_settings->c_iflag |= (BRKINT
- | IGNPAR
- | ICRNL
- | IXON
-#ifdef IMAXBEL
- | IMAXBEL
-#endif
- );
+ | IGNPAR
+ | ISTRIP
+ | ICRNL /* Input maps CR to NL */
+ | IXON);
- tty_settings->c_oflag &= ~((unsigned) (0
-#ifdef OLCUC
- | OLCUC
-#endif
-#ifdef OCRNL
- | OCRNL
-#endif
-#ifdef ONOCR
- | ONOCR
-#endif
-#ifdef ONLRET
- | ONLRET
-#endif
-#ifdef OFILL
- | OFILL
-#endif
-#ifdef OFDEL
- | OFDEL
-#endif
-#ifdef NLDLY
- | NLDLY
-#endif
-#ifdef CRDLY
- | CRDLY
-#endif
-#ifdef TABDLY
- | TABDLY
-#endif
-#ifdef BSDLY
- | BSDLY
-#endif
-#ifdef VTDLY
- | VTDLY
-#endif
-#ifdef FFDLY
- | FFDLY
-#endif
- ));
+ tty_settings->c_iflag &= ~(INLCR); /* Input does not map NL to CR */
tty_settings->c_oflag |= (OPOST
#ifdef ONLCR
- | ONLCR
+ | ONLCR /* Output maps NL to CR-NL */
#endif
- );
+ );
- tty_settings->c_cflag &= ~((unsigned) (CSIZE
- | CSTOPB
- | PARENB
- | PARODD
- | CLOCAL));
- tty_settings->c_cflag |= (CS8 | CREAD);
- tty_settings->c_lflag &= ~((unsigned) (ECHONL
- | NOFLSH
-#ifdef TOSTOP
- | TOSTOP
-#endif
-#ifdef ECHOPTR
- | ECHOPRT
-#endif
-#ifdef XCASE
- | XCASE
-#endif
- ));
-
- tty_settings->c_lflag |= (ISIG
+ tty_settings->c_lflag |= (ISIG /* Generate signal on ^C, ^Z, etc
*/
| ICANON
| ECHO
| ECHOE
@@ -327,7 +272,7 @@
| ECHOKE
#endif
);
-#endif
+#endif /* Matches #ifdef TERMIOS */
if (!noset) {
SET_TTY(fd, tty_settings);
