Add functionality to only list hosts specified on the command line. If none

are specified the old behaviour is old.  The submitted applied a much cleaner
diff to ruptime.c, however it did not cover cases like listing failures.  It
would probably be a good idea to move the printing from the ruptime function,
and have that function just be used to build the list, as that would unbreak
sorting, but this diff is intended to be clear, relative to the original
code.  As the sort order is the order specified on the command line, for now,
such is documented in the manual page accordingly.

Submitted by:	Edward J. M. Blocklesby <ejb@lythe.org.uk>
MFC after:	3 weeks

2 files changed, 101 insertions, 67 deletions

diff --git a/usr.bin/ruptime/ruptime.1 b/usr.bin/ruptime/ruptime.1
index f15153a..1ef1eb9 100644
--- a/usr.bin/ruptime/ruptime.1
+++ b/usr.bin/ruptime/ruptime.1
@@ -41,6 +41,7 @@
 .Sh SYNOPSIS
 .Nm
 .Op Fl alrtu
+.Op Ar host ...
 .Sh DESCRIPTION
 The
 .Nm
@@ -49,6 +50,13 @@ utility gives a status line like
 for each machine on the local network; these are formed from packets
 broadcast by each host on the network once every three minutes.
 .Pp
+If no operands are given,
+.Nm
+displays uptime status for all machines;
+otherwise only those hosts specified on the command line are displayed.
+If hosts are specified on the command line, the sort order is equivalent
+to the order hosts were specified on the command line.
+.Pp
 Machines for which no status report has been received for 11
 minutes are shown as being down, and machines for which no status
 report has been received for 4 days are not shown in the list at all.
diff --git a/usr.bin/ruptime/ruptime.c b/usr.bin/ruptime/ruptime.c
index 58c8789..32f85aa 100644
--- a/usr.bin/ruptime/ruptime.c
+++ b/usr.bin/ruptime/ruptime.c
@@ -70,11 +70,13 @@ struct	whod awhod;
 size_t nhosts;
 time_t now;
 int rflg = 1;
+DIR *dirp;
 
 int	 hscmp(const void *, const void *);
 char	*interval(time_t, const char *);
 int	 lcmp(const void *, const void *);
 void	 morehosts(void);
+void	 ruptime(const char *, int, int (*)(const void *, const void *));
 int	 tcmp(const void *, const void *);
 int	 ucmp(const void *, const void *);
 void	 usage(void);
@@ -82,16 +84,8 @@ void	 usage(void);
 int
 main(int argc, char *argv[])
 {
-	struct dirent *dp;
-	struct hs *hsp;
-	struct whod *wd;
-	struct whoent *we;
-	DIR *dirp;
-	size_t hspace;
-	int aflg, ch, fd, i, maxloadav;
-	char buf[sizeof(struct whod)];
 	int (*cmp)(const void *, const void *);
-	u_int cc;
+	int aflg, ch;
 
 	aflg = 0;
 	cmp = hscmp;
@@ -118,15 +112,87 @@ main(int argc, char *argv[])
 	argc -= optind;
 	argv += optind;
 
-	if (argc != 0)
-		usage();
-
 	if (chdir(_PATH_RWHODIR) || (dirp = opendir(".")) == NULL)
 		err(1, "%s", _PATH_RWHODIR);
 
+	ruptime(*argv, aflg, cmp);
+	while (*argv++ != NULL) {
+		if (*argv == NULL)
+			break;
+		ruptime(*argv, aflg, cmp);
+	}
+	exit(0);
+}
+
+char *
+interval(time_t tval, const char *updown)
+{
+	static char resbuf[32];
+	int days, hours, minutes;
+
+	if (tval < 0) {
+		(void)snprintf(resbuf, sizeof(resbuf), "   %s ??:??", updown);
+		return (resbuf);
+	}
+						/* round to minutes. */
+	minutes = (tval + (60 - 1)) / 60;
+	hours = minutes / 60;
+	minutes %= 60;
+	days = hours / 24;
+	hours %= 24;
+	if (days)
+		(void)snprintf(resbuf, sizeof(resbuf),
+		    "%s %3d+%02d:%02d", updown, days, hours, minutes);
+	else
+		(void)snprintf(resbuf, sizeof(resbuf),
+		    "%s     %2d:%02d", updown, hours, minutes);
+	return (resbuf);
+}
+
+#define	HS(a)	((const struct hs *)(a))
+
+/* Alphabetical comparison. */
+int
+hscmp(const void *a1, const void *a2)
+{
+	return (rflg *
+	    strcmp(HS(a1)->hs_wd->wd_hostname, HS(a2)->hs_wd->wd_hostname));
+}
+
+/* Load average comparison. */
+int
+lcmp(const void *a1, const void *a2)
+{
+	if (ISDOWN(HS(a1)))
+		if (ISDOWN(HS(a2)))
+			return (tcmp(a1, a2));
+		else
+			return (rflg);
+	else if (ISDOWN(HS(a2)))
+		return (-rflg);
+	else
+		return (rflg *
+		   (HS(a2)->hs_wd->wd_loadav[0] - HS(a1)->hs_wd->wd_loadav[0]));
+}
+
+void
+ruptime(const char *host, int aflg, int (*cmp)(const void *, const void *))
+{
+	struct hs *hsp;
+	struct whod *wd;
+	struct whoent *we;
+	struct dirent *dp;
+	const char *hostname;
+	char buf[sizeof(struct whod)];
+	int fd, i, maxloadav;
+	size_t hspace;
+	u_int cc;
+
+	rewinddir(dirp);
+	hsp = NULL;
 	maxloadav = -1;
 	for (nhosts = hspace = 0; (dp = readdir(dirp)) != NULL;) {
-		if (dp->d_ino == 0 || strncmp(dp->d_name, "whod.", 5))
+		if (dp->d_ino == 0 || strncmp(dp->d_name, "whod.", 5) != 0)
 			continue;
 		if ((fd = open(dp->d_name, O_RDONLY, 0)) < 0) {
 			warn("%s", dp->d_name);
@@ -134,6 +200,11 @@ main(int argc, char *argv[])
 		}
 		cc = read(fd, buf, sizeof(struct whod));
 		(void)close(fd);
+		if (host != NULL) {
+			hostname = ((struct whod *)buf)->wd_hostname;
+			if (strcasecmp(hostname, host) != 0)
+				continue;
+		}
 
 		if (cc < WHDRSIZE)
 			continue;
@@ -159,8 +230,12 @@ main(int argc, char *argv[])
 		++hsp;
 		++nhosts;
 	}
-	if (nhosts == 0)
-		errx(1, "no hosts in %s", _PATH_RWHODIR);
+	if (nhosts == 0) {
+		if (host == NULL)
+			errx(1, "no hosts in %s", _PATH_RWHODIR);
+		else
+			warnx("host %s not in %s", host, _PATH_RWHODIR);
+	}
 
 	(void)time(&now);
 	qsort(hs, nhosts, sizeof(hs[0]), cmp);
@@ -186,59 +261,10 @@ main(int argc, char *argv[])
 		        hsp->hs_wd->wd_loadav[1] / 100.0,
 		    maxloadav >= 1000 ? 5 : 4,
 		        hsp->hs_wd->wd_loadav[2] / 100.0);
+		free(hsp->hs_wd);
 	}
-	exit(0);
-}
-
-char *
-interval(time_t tval, const char *updown)
-{
-	static char resbuf[32];
-	int days, hours, minutes;
-
-	if (tval < 0) {
-		(void)snprintf(resbuf, sizeof(resbuf), "   %s ??:??", updown);
-		return (resbuf);
-	}
-						/* round to minutes. */
-	minutes = (tval + (60 - 1)) / 60;
-	hours = minutes / 60;
-	minutes %= 60;
-	days = hours / 24;
-	hours %= 24;
-	if (days)
-		(void)snprintf(resbuf, sizeof(resbuf),
-		    "%s %3d+%02d:%02d", updown, days, hours, minutes);
-	else
-		(void)snprintf(resbuf, sizeof(resbuf),
-		    "%s     %2d:%02d", updown, hours, minutes);
-	return (resbuf);
-}
-
-#define	HS(a)	((const struct hs *)(a))
-
-/* Alphabetical comparison. */
-int
-hscmp(const void *a1, const void *a2)
-{
-	return (rflg *
-	    strcmp(HS(a1)->hs_wd->wd_hostname, HS(a2)->hs_wd->wd_hostname));
-}
-
-/* Load average comparison. */
-int
-lcmp(const void *a1, const void *a2)
-{
-	if (ISDOWN(HS(a1)))
-		if (ISDOWN(HS(a2)))
-			return (tcmp(a1, a2));
-		else
-			return (rflg);
-	else if (ISDOWN(HS(a2)))
-		return (-rflg);
-	else
-		return (rflg *
-		   (HS(a2)->hs_wd->wd_loadav[0] - HS(a1)->hs_wd->wd_loadav[0]));
+	free(hs);
+	hs = NULL;
 }
 
 /* Number of users comparison. */