scroll

commit 6d1a3bbbb870a303b47f790ba76146e61a4c7b6a
parent 6b13c34098454e6e667aca6bf37c47feedc0d185
Author: Jan Klemkow <j.klemkow@wemelug.de>
Date:   Tue, 28 Apr 2020 21:20:42 +0200

avoid race condition with sigwinch

if sigwinch comes before forking the child process,
we are traped into an endless loop.  because, the
variable child is zero.  Thus, we propagating sigwinch
to ourself in the signal handler.

Diffstat:
M
scroll.c
 | 
6
+++---

1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/scroll.c b/scroll.c
@@ -428,9 +428,6 @@ main(int argc, char *argv[])
 	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1)
 		die("ioctl:");
 
-	if (signal(SIGWINCH, sigwinch) == SIG_ERR)
-		die("signal:");
-
 	child = forkpty(&mfd, NULL, &dfl, &ws);
 	if (child == -1)
 		die("forkpty:");
@@ -457,6 +454,9 @@ main(int argc, char *argv[])
 		die("pledge:");
 #endif
 
+	if (signal(SIGWINCH, sigwinch) == SIG_ERR)
+		die("signal:");
+
 	struct termios new = dfl;
 	cfmakeraw(&new);
 	new.c_cc[VMIN ] = 1;	/* return read if at least one byte in buffer */