add -4 and -6 option to be able to specify an address family.

Requested by:	matusita
MFC after:	1 week

3 files changed, 22 insertions, 4 deletions

diff --git a/usr.bin/finger/finger.1 b/usr.bin/finger/finger.1
index 432d762..4c00c54 100644
--- a/usr.bin/finger/finger.1
+++ b/usr.bin/finger/finger.1
@@ -40,7 +40,7 @@
 .Nd user information lookup program
 .Sh SYNOPSIS
 .Nm
-.Op Fl glmpshoT
+.Op Fl 46glmpshoT
 .Op Ar user ...\&
 .Op Ar user@host ...\&
 .Sh DESCRIPTION
@@ -50,6 +50,14 @@ utility displays information about the system users.
 .Pp
 Options are:
 .Bl -tag -width flag
+.It Fl 4
+Forces
+.Nm
+to use IPv4 addresses only.
+.It Fl 6
+Forces
+.Nm
+to use IPv6 addresses only.
 .It Fl s
 Display the user's login name, real name, terminal name and write
 status (as a ``*'' before the terminal name if write permission is
diff --git a/usr.bin/finger/finger.c b/usr.bin/finger/finger.c
index 0e6c176..a695672 100644
--- a/usr.bin/finger/finger.c
+++ b/usr.bin/finger/finger.c
@@ -73,6 +73,8 @@ __FBSDID("$FreeBSD$");
  * well as home directory, shell, mail info, and .plan/.project files.
  */
 
+#include <sys/types.h>
+#include <sys/socket.h>
 #include <db.h>
 #include <err.h>
 #include <pwd.h>
@@ -90,6 +92,7 @@ __FBSDID("$FreeBSD$");
 DB *db;
 time_t now;
 int entries, gflag, lflag, mflag, pplan, sflag, oflag, Tflag;
+sa_family_t family = PF_UNSPEC;
 int d_first = -1;
 char tbuf[1024];
 
@@ -107,8 +110,14 @@ option(argc, argv)
 
 	optind = 1;		/* reset getopt */
 
-	while ((ch = getopt(argc, argv, "glmpshoT")) != -1)
+	while ((ch = getopt(argc, argv, "46glmpshoT")) != -1)
 		switch(ch) {
+		case '4':
+			family = AF_INET;
+			break;
+		case '6':
+			family = AF_INET6;
+			break;
 		case 'g':
 			gflag = 1;
 			break;
@@ -144,7 +153,7 @@ option(argc, argv)
 static void
 usage()
 {
-	(void)fprintf(stderr, "usage: finger [-lmpshoT] [login ...]\n");
+	(void)fprintf(stderr, "usage: finger [-46lmpshoT] [login ...]\n");
 	exit(1);
 }
 
diff --git a/usr.bin/finger/net.c b/usr.bin/finger/net.c
index 67a7087..b4df124 100644
--- a/usr.bin/finger/net.c
+++ b/usr.bin/finger/net.c
@@ -60,6 +60,7 @@ __FBSDID("$FreeBSD$");
 
 extern int lflag;		/* XXX finger.h? */
 extern int Tflag;		/* XXX finger.h? */
+extern sa_family_t family;
 
 static void cleanup(int sig);;
 static int do_protocol(const char *name, const struct addrinfo *ai);
@@ -82,7 +83,7 @@ netfinger(name)
 	alarm(TIME_LIMIT);
 
 	hint.ai_flags = AI_CANONNAME;
-	hint.ai_family = PF_UNSPEC;
+	hint.ai_family = family;
 	hint.ai_socktype = SOCK_STREAM;
 
 	error = getaddrinfo(host, "finger", &hint, &ai0);