sob

commit 7a89c043b1e2c774e6522b3b1b3a4114354ee0fd
parent 7eae1acf0a7d4644114e30f6f3bfc2143954518c
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Sat, 25 Oct 2014 11:12:50 +0000

improve tcgetattr and setup()

- don't restore attributes if tcgetattr failed.
- tcgetattr indicates if it's isatty().

Diffstat:
M
sob.c
 | 
57
++++++++++++++++++++++++++++++++++++---------------------

1 file changed, 36 insertions(+), 21 deletions(-)
diff --git a/sob.c b/sob.c
@@ -756,14 +756,29 @@ sighandler(int signum)
 static void
 setup(void)
 {
-	tcgetattr(STDIN_FILENO, &ttystate);
-	ttysave = ttystate;
-	/* turn off canonical mode and echo */
-	ttystate.c_lflag &= ~(ICANON | ECHO);
-	ttystate.c_cc[VMIN] = 1;
-
-	/* set the terminal attributes */
-	tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
+	if(tcgetattr(STDIN_FILENO, &ttystate) == 0) {
+		termattrset = 1;
+		ttysave = ttystate;
+		/* turn off canonical mode and echo */
+		ttystate.c_lflag &= ~(ICANON | ECHO);
+		ttystate.c_cc[VMIN] = 1;
+		/* set the terminal attributes */
+		tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
+	} else {
+		/* not a tty */
+		initialinput();
+		/* setup tty again because we (re)open "/dev/tty" */
+		termattrset = 0;
+		if(tcgetattr(STDIN_FILENO, &ttystate) == 0) {
+			termattrset = 1;
+			ttysave = ttystate;
+			/* turn off canonical mode and echo */
+			ttystate.c_lflag &= ~(ICANON | ECHO);
+			ttystate.c_cc[VMIN] = 1;
+			/* set the terminal attributes */
+			tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
+		}
+	}
 	/* get terminal window size */
 	gettermsize();
 }
@@ -900,10 +915,12 @@ initialinput(void)
 		buf[r] = '\0';
 		handleinput(buf, r);
 	}
-	/* restore terminal attributes. */
-	ttystate.c_lflag = ttysave.c_lflag;
-	tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
-	/* close and reattach to stdin */
+	/* restore terminal attributes */
+	if(termattrset) {
+		ttystate.c_lflag = ttysave.c_lflag;
+		tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
+	}
+	/* close and re-attach to stdin */
 	close(STDIN_FILENO);
 	if((fd = open("/dev/tty", O_RDONLY | O_NONBLOCK)) == -1) {
 		fprintf(stderr, "open: /dev/tty: %s\n", strerror(errno));
@@ -931,7 +948,6 @@ main(int argc, char **argv)
 	lineoutfp = stdout;
 	outfp = stderr;
 	setlocale(LC_ALL, "");
-	setup();
 
 	/* signal handling */
 	memset(&sa, 0, sizeof(sa));
@@ -943,18 +959,17 @@ main(int argc, char **argv)
 	sa.sa_handler = SIG_IGN;
 	sigaction(SIGCHLD, &sa, NULL);
 
-	if(!isatty(STDIN_FILENO)) {
-		initialinput();
-		/* setup tty again because we (re)open "/dev/tty" */
-		setup();
-	}
+	setup();
+
 	/* clear screen */
 	clear();
 	run();
 
-	/* cleanup: restore terminal attributes. */
-	ttystate.c_lflag = ttysave.c_lflag;
-	tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
+	/* cleanup: restore terminal attributes */
+	if(termattrset) {
+		ttystate.c_lflag = ttysave.c_lflag;
+		tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
+	}
 
 	return EXIT_SUCCESS;
 }