main: rework terminal-based settings somewhat

As pointed out by slyfox, the result from ioctl was ignored and its
result used anyway.  While at it to fix this, rework the logic somewhat,
such that terminal width and colours are always disabled when we're not
dealing with a TTY.

Bug: https://bugs.gentoo.org/689290#c14
Signed-off-by: Fabian Groffen <grobian@gentoo.org>

1 files changed, 9 insertions, 7 deletions

diff --git a/main.c b/main.c
index c5cc4b4c..bdbb2a7b 100644
--- a/main.c
+++ b/main.c
@@ -780,9 +780,6 @@ int main(int argc, char **argv)
 	struct stat st;
 	struct winsize winsz;
 
-	ioctl(0, TIOCGWINSZ, &winsz);
-	twidth = winsz.ws_col > 0 ? (int)winsz.ws_col : 80;
-
 	warnout = stderr;
 	IF_DEBUG(init_coredumps());
 	argv0 = argv[0];
@@ -791,13 +788,18 @@ int main(int argc, char **argv)
 	bindtextdomain(argv0, CONFIG_EPREFIX "usr/share/locale");
 	textdomain(argv0);
 
-	if (fstat(fileno(stdout), &st) != -1)
+	twidth = 0;
+	if (fstat(fileno(stdout), &st) != -1) {
 		if (!isatty(fileno(stdout))) {
 			no_colors();
-			twidth = 0;
+		} else {
+			if ((getenv("TERM") == NULL) ||
+					(strcmp(getenv("TERM"), "dumb") == 0))
+				no_colors();
+			if (ioctl(0, TIOCGWINSZ, &winsz) == 0 && winsz.ws_col > 0)
+				twidth = (int)winsz.ws_col;
 		}
-	if ((getenv("TERM") == NULL) || (strcmp(getenv("TERM"), "dumb") == 0))
-		no_colors();
+	}
 
 	initialize_portage_env();
 	optind = 0;