Fix TTY size precedence

Precedence order: environment variables, TIOCGWINSZ, terminfo

Makefile.am

@@ -4,7 +4,7 @@ AM_CFLAGS=-pedantic -Wall -Werror -Wextra
 AM_CPPFLAGS=-D_GNU_SOURCE
 
 bin_PROGRAMS=pick
-dist_pick_SOURCES=pick.c compat-reallocarray.c compat.h
+dist_pick_SOURCES=pick.c compat-reallocarray.c compat-strtonum.c compat.h
 dist_man_MANS=pick.1
 
 TESTS=tests/01.t tests/02.t tests/03.t tests/04.t tests/05.t tests/06.t \

compat-strtonum.c

@@ -0,0 +1,75 @@
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+int unused;
+
+#ifndef HAVE_STRTONUM
+
+/*	$OpenBSD: strtonum.c,v 1.8 2015/09/13 08:31:48 guenther Exp $	*/
+
+/*
+ * Copyright (c) 2004 Ted Unangst and Todd Miller
+ * All rights reserved.
+ *
+ * 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 <errno.h>
+#include <limits.h>
+#include <stdlib.h>
+
+#define	INVALID		1
+#define	TOOSMALL	2
+#define	TOOLARGE	3
+
+long long
+strtonum(const char *numstr, long long minval, long long maxval,
+    const char **errstrp)
+{
+	long long ll = 0;
+	int error = 0;
+	char *ep;
+	struct errval {
+		const char *errstr;
+		int err;
+	} ev[4] = {
+		{ NULL,		0 },
+		{ "invalid",	EINVAL },
+		{ "too small",	ERANGE },
+		{ "too large",	ERANGE },
+	};
+
+	ev[0].err = errno;
+	errno = 0;
+	if (minval > maxval) {
+		error = INVALID;
+	} else {
+		ll = strtoll(numstr, &ep, 10);
+		if (numstr == ep || *ep != '\0')
+			error = INVALID;
+		else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
+			error = TOOSMALL;
+		else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval)
+			error = TOOLARGE;
+	}
+	if (errstrp != NULL)
+		*errstrp = ev[error].errstr;
+	errno = ev[error].err;
+	if (error)
+		ll = 0;
+
+	return (ll);
+}
+
+#endif /* !HAVE_STRTONUM */

compat.h

@@ -25,4 +25,10 @@ void	*reallocarray(void *, size_t, size_t);
 
 #endif /* !HAVE_REALLOCARRAY */
 
+#ifndef HAVE_STRTONUM
+
+long long	strtonum(const char *, long long, long long, const char **);
+
+#endif /* !HAVE_STRTONUM */
+
 #endif /* COMPAT_H */

config.h.in

@@ -9,6 +9,9 @@
 /* Define to 1 if you have the `reallocarray' function. */
 #undef HAVE_REALLOCARRAY
 
+/* Define to 1 if you have the `strtonum' function. */
+#undef HAVE_STRTONUM
+
 /* Name of package */
 #undef PACKAGE
 

configure.ac

@@ -4,7 +4,7 @@ AM_INIT_AUTOMAKE([subdir-objects])
 AC_CONFIG_HEADERS([config.h])
 AC_PROG_CC
 AM_PROG_CC_C_O
-AC_CHECK_FUNCS([pledge reallocarray])
+AC_CHECK_FUNCS([pledge reallocarray strtonum])
 AC_SEARCH_LIBS([setupterm], [curses], [],
   [
     AC_SEARCH_LIBS([setupterm], [ncursesw],

pick.c

@@ -702,15 +702,31 @@ tty_restore(void)
 void
 tty_size(void)
 {
-	struct winsize	ws;
+	const char	*cp;
+	struct winsize	 ws;
+	int		 sz;
 
 	if (ioctl(fileno(tty_in), TIOCGWINSZ, &ws) != -1) {
 		tty_columns = ws.ws_col;
 		tty_lines = ws.ws_row;
-	} else {
+	}
+
+	if (tty_columns == 0)
 		tty_columns = tigetnum("cols");
+	if (tty_lines == 0)
 		tty_lines = tigetnum("lines");
-	}
+
+	if ((cp = getenv("COLUMNS")) != NULL &&
+	    (sz = strtonum(cp, 1, INT_MAX, NULL)) > 0)
+		tty_columns = sz;
+	if ((cp = getenv("LINES")) != NULL &&
+	    (sz = strtonum(cp, 1, INT_MAX, NULL)) > 0)
+		tty_lines = sz;
+
+	if (tty_columns == 0)
+		tty_columns = 80;
+	if (tty_lines == 0)
+		tty_lines = 24;
 
 	choices_lines = tty_lines - 1;	/* available lines, minus query line */
 }