From: finxx <me@finxx.xyz>
Subject: Implement tcgetwinsize and tcsetwinsize
To: tech@openbsd.org
Date: Sun, 23 Feb 2025 16:13:42 -0600

tcgetwinsize(3) and tcsetwinsize(3) have existed in POSIX for years, and
been supported on the other BSDs for just as long. This patch implements
them in libc.

diff 11d817a3382201927643a2ae0a36dcc4048bfb0b HEAD
commit - 11d817a3382201927643a2ae0a36dcc4048bfb0b
commit + c077581a317e8f39c250c631d6d29b01a97e7f8a
blob - 6eb2cca93e5f1c834a57a03af4a4b3fe27c64ce1
blob + 18cf144e7a06b88f2514407c57cda12d192d7709
--- lib/libc/Symbols.list
+++ lib/libc/Symbols.list
@@ -1700,9 +1700,11 @@ tcflush
 tcgetattr
 tcgetpgrp
 tcgetsid
+tcgetwinsize
 tcsendbreak
 tcsetattr
 tcsetpgrp
+tcsetwinsize
 
 /* thread */
 _rthread_debug
blob - 85c1d52273c9cb24478c2c7e67a79bbdd86dae51
blob + a1aff88ae34741f62149e88c69c93f6b5b7326c6
--- lib/libc/termios/Makefile.inc
+++ lib/libc/termios/Makefile.inc
@@ -4,6 +4,7 @@
 
 SRCS+=	cfgetispeed.c cfgetospeed.c cfmakeraw.c cfsetispeed.c cfsetospeed.c \
 	cfsetspeed.c tcdrain.c tcflow.c tcflush.c tcgetattr.c tcgetpgrp.c \
-	tcsendbreak.c tcsetattr.c tcsetpgrp.c tcgetsid.c
+	tcsendbreak.c tcsetattr.c tcsetpgrp.c tcgetsid.c tcgetwinsize.c \
+	tcsetwinsize.c
 
 MAN+=	tcgetpgrp.3 tcsendbreak.3 tcsetattr.3 tcsetpgrp.3 tcgetsid.3
blob - /dev/null
blob + c41b49129a7c60230f20f727ce90f7e4b089cd30 (mode 644)
--- /dev/null
+++ lib/libc/termios/tcgetwinsize.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2025 Finxx <me@finxx.xyz>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/ioctl.h>
+#include <termios.h>
+
+int
+tcgetwinsize(int fd, struct winsize *winsize_p)
+{
+	return (ioctl(fd, TIOCGWINSZ, winsize_p));
+}
blob - /dev/null
blob + 7e652d5f8457bb752b724c14cbfbdd9dc15f0564 (mode 644)
--- /dev/null
+++ lib/libc/termios/tcsetwinsize.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2025 Finxx <me@finxx.xyz>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/ioctl.h>
+#include <termios.h>
+
+int
+tcsetwinsize(int fd, const struct winsize *winsize_p)
+{
+	return (ioctl(fd, TIOCSWINSZ, winsize_p));
+}
blob - 681c29489138850507516a8ef6bc346bed04e4e9
blob + 62a2d7a676481ae3fd947c15e237d4a5b018c1ca
--- sys/sys/termios.h
+++ sys/sys/termios.h
@@ -272,6 +272,8 @@ int	tcdrain(int);
 int	tcflow(int, int);
 int	tcflush(int, int);
 int	tcsendbreak(int, int);
+int	tcgetwinsize(int, struct winsize *);
+int	tcsetwinsize(int, const struct winsize *);
 
 #if __XPG_VISIBLE >= 420 || __POSIX_VISIBLE >= 200809
 pid_t	tcgetsid(int);