Add support for COLUMNS env variable, inspired by FreeBSD but with a dash

of strtonum() from millert@ sprinkled on top.
Also, we've always supported TZ for formatting dates, so say so.

ok jmc@ millert@

2 files changed, 38 insertions, 19 deletions

diff --git a/bin/ps/ps.1 b/bin/ps/ps.1
index c7f49567ece..2a52b97b483 100644
--- a/bin/ps/ps.1
+++ b/bin/ps/ps.1
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: ps.1,v 1.94 2014/05/21 06:01:19 jmc Exp $
+.\"	$OpenBSD: ps.1,v 1.95 2014/06/05 07:29:20 guenther Exp $
 .\"	$NetBSD: ps.1,v 1.16 1996/03/21 01:36:28 jtc Exp $
 .\"
 .\" Copyright (c) 1980, 1990, 1991, 1993, 1994
@@ -30,7 +30,7 @@
 .\"
 .\"     @(#)ps.1	8.3 (Berkeley) 4/18/94
 .\"
-.Dd $Mdocdate: May 21 2014 $
+.Dd $Mdocdate: June 5 2014 $
 .Dt PS 1
 .Os
 .Sh NAME
@@ -527,6 +527,21 @@ as 324000.
 .It Cm xstat
 Exit or stop status (valid only for stopped or zombie process).
 .El
+.Sh ENVIRONMENT
+The following environment variables affect the execution of
+.Nm :
+.Bl -tag -width "COLUMNS"
+.It Ev COLUMNS
+If set, specifies the user's preferred output width in column positions.
+By default,
+.Nm
+attempts to automatically determine the terminal width.
+.It Ev TZ
+The time zone to use when displaying dates.
+See
+.Xr environ 7
+for more information.
+.El
 .Sh FILES
 .Bl -tag -width "/var/db/kvm_bsd.dbXXX" -compact
 .It Pa /dev
@@ -567,15 +582,10 @@ utility is compliant with the
 specification,
 except that the flag
 .Op Fl G
-is unsupported,
+is unsupported and
 the flags
 .Op Fl ptU
-support only single arguments, not lists,
-and the environment variables
-.Ev COLUMNS
-and
-.Ev TZ
-are unsupported.
+support only single arguments, not lists.
 .Pp
 The flags
 .Op Fl defglnu
diff --git a/bin/ps/ps.c b/bin/ps/ps.c
index 608ddd78804..4456af835ce 100644
--- a/bin/ps/ps.c
+++ b/bin/ps/ps.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ps.c,v 1.60 2014/05/07 01:31:25 tedu Exp $	*/
+/*	$OpenBSD: ps.c,v 1.61 2014/06/05 07:29:20 guenther Exp $	*/
 /*	$NetBSD: ps.c,v 1.15 1995/05/18 20:33:25 mycroft Exp $	*/
 
 /*-
@@ -98,15 +98,24 @@ main(int argc, char *argv[])
 	uid_t uid;
 	int all, ch, flag, i, fmt, lineno, nentries;
 	int prtheader, showthreads, wflag, kflag, what, Uflag, xflg;
-	char *nlistf, *memf, *swapf, errbuf[_POSIX2_LINE_MAX];
-
-	if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 &&
-	    ioctl(STDERR_FILENO, TIOCGWINSZ, &ws) == -1 &&
-	    ioctl(STDIN_FILENO,  TIOCGWINSZ, &ws) == -1) ||
-	    ws.ws_col == 0)
-		termwidth = 79;
-	else
-		termwidth = ws.ws_col - 1;
+	char *nlistf, *memf, *swapf, *cols, errbuf[_POSIX2_LINE_MAX];
+
+	if ((cols = getenv("COLUMNS")) != NULL && *cols != '\0') {
+		const char *errstr;
+
+		termwidth = strtonum(cols, 1, INT_MAX, &errstr);
+		if (errstr != NULL)
+			warnx("COLUMNS: %s: %s", cols, errstr);
+	}
+	if (termwidth == 0) {
+		if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 &&
+		    ioctl(STDERR_FILENO, TIOCGWINSZ, &ws) == -1 &&
+		    ioctl(STDIN_FILENO,  TIOCGWINSZ, &ws) == -1) ||
+		    ws.ws_col == 0)
+			termwidth = 79;
+		else
+			termwidth = ws.ws_col - 1;
+	}
 
 	if (argc > 1)
 		argv[1] = kludge_oldps_options(argv[1]);