Refactor chvt(1)

1) Properly implement arg.h.
2) Use estrtonum instead of estrtol.
3) Check close().
4) Small fixes.
5) Update manpage.

Makefile

@@ -31,6 +31,7 @@ LIBUTILSRC = \
 	libutil/recurse.c        \
 	libutil/strlcat.c        \
 	libutil/strlcpy.c        \
+	libutil/strtonum.c       \
 	libutil/tty.c
 
 LIB = $(LIBUTIL)

chvt.1

@@ -1,4 +1,4 @@
-.Dd February 2, 2015
+.Dd September 7, 2015
 .Dt CHVT 1
 .Os ubase
 .Sh NAME
@@ -6,9 +6,10 @@
 .Nd change foreground virtual terminal
 .Sh SYNOPSIS
 .Nm
-.Ar N
+.Ar num
 .Sh DESCRIPTION
 .Nm
 brings
-.Pf /dev/tty Ar N
-to the foreground. This has the same effect as Ctrl-Alt-FN.
+.Pf /dev/tty Ar num
+to the foreground. This has the same effect as
+.Pf Ctrl-Alt-F Ar num .

chvt.c

@@ -3,8 +3,8 @@
 #include <sys/types.h>
 
 #include <fcntl.h>
+#include <limits.h>
 #include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 
@@ -15,7 +15,7 @@
 #define VT_ACTIVATE	0x5606	/* make vt active */
 #define VT_WAITACTIVE	0x5607	/* wait for vt active */
 
-static char *vts[] = {
+static char *vt[] = {
 	"/proc/self/fd/0",
 	"/dev/console",
 	"/dev/tty",
@@ -25,7 +25,7 @@ static char *vts[] = {
 static void
 usage(void)
 {
-	eprintf("usage: %s N\n", argv0);
+	eprintf("usage: %s num\n", argv0);
 }
 
 int
@@ -36,29 +36,32 @@ main(int argc, char *argv[])
 	char c;
 
 	ARGBEGIN {
+	default:
+		usage();
 	} ARGEND;
 
-	if (argc != 2 || strspn(argv[1], "1234567890") != strlen(argv[1]))
+	if (argc != 1)
 		usage();
 
-	n = estrtol(argv[1], 10);
-	for (i = 0; i < LEN(vts); i++) {
-		fd = open(vts[i], O_RDONLY);
-		if (fd < 0)
+	n = estrtonum(argv[0], 0, UINT_MAX);
+	for (i = 0; i < LEN(vt); i++) {
+		if ((fd = open(vt[i], O_RDONLY)) < 0)
 			continue;
 		c = 0;
 		if (ioctl(fd, KDGKBTYPE, &c) == 0)
-			goto VTfound;
-		close(fd);
+			goto found;
+		if (close(fd) < 0)
+			eprintf("close %s:", vt[i]);
 	}
+	eprintf("no console found\n");
 
-	eprintf("couldn't find a console.\n");
-VTfound:
+found:
 	if (ioctl(fd, VT_ACTIVATE, n) == -1)
-		eprintf("VT_ACTIVATE %d:", n);
+		eprintf("VT_ACTIVATE %u:", n);
 	if (ioctl(fd, VT_WAITACTIVE, n) == -1)
-		eprintf("VT_WAITACTIVE %d:", n);
-	close(fd);
+		eprintf("VT_WAITACTIVE %u:", n);
+	if (close(fd) < 0)
+		eprintf("close %s:", vt[i]);
 
 	return 0;
 }

libutil/strtonum.c

@@ -0,0 +1,85 @@
+/*	$OpenBSD: strtonum.c,v 1.7 2013/04/17 18:40:58 tedu 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>
+
+#include "../util.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);
+}
+
+long long
+enstrtonum(int status, const char *numstr, long long minval, long long maxval)
+{
+	const char *errstr;
+	long long ll;
+
+	ll = strtonum(numstr, minval, maxval, &errstr);
+	if (errstr)
+		enprintf(status, "strtonum %s: %s\n", numstr, errstr);
+	return ll;
+}
+
+long long
+estrtonum(const char *numstr, long long minval, long long maxval)
+{
+	return enstrtonum(1, numstr, minval, maxval);
+}

util.h

@@ -50,6 +50,12 @@ size_t estrlcat(char *, const char *, size_t);
 size_t strlcpy(char *, const char *, size_t);
 size_t estrlcpy(char *, const char *, size_t);
 
+/* strtonum.c */
+#undef strtonum
+long long strtonum(const char *, long long, long long, const char **);
+long long enstrtonum(int, const char *, long long, long long);
+long long estrtonum(const char *, long long, long long);
+
 /* tty.c */
 void devtotty(int, int *, int *);
 int ttytostr(int, int, char *, size_t);