tcpdrop usage()

[Lawrence Teo]

This diff replaces "goto fail" in tcpdrop with a proper usage() to be
consistent with other programs in the tree.

ok?


Index: tcpdrop.c
===================================================================
RCS file: /cvs/src/usr.sbin/tcpdrop/tcpdrop.c,v
retrieving revision 1.15
diff -u -p -r1.15 tcpdrop.c
--- tcpdrop.c   1 Jan 2015 03:27:56 -0000       1.15
+++ tcpdrop.c   4 Jan 2015 04:49:48 -0000
@@ -33,7 +33,21 @@
 #include <stdlib.h>
 #include <netdb.h>
 
-extern char *__progname;
+__dead void     usage(void);
+
+__dead void
+usage(void)
+{
+       extern char     *__progname;
+
+       fprintf(stderr,
+           "usage: %s local-addr local-port remote-addr remote-port\n",
+           __progname);
+       fprintf(stderr,
+           "       %s local-addr:local-port remote-addr:remote-port\n",
+           __progname);
+       exit(1);
+}
 
 /*
  * Drop a tcp connection.
@@ -61,7 +75,7 @@ main(int argc, char **argv)
                if (port1)
                        *port1++ = '\0';
                else
-                       goto fail;
+                       usage();
 
                faddr2 = addr2 = strdup(argv[2]);
                if (!addr2)
@@ -70,22 +84,14 @@ main(int argc, char **argv)
                if (port2)
                        *port2++ = '\0';
                else
-                       goto fail;
+                       usage();
        } else if (argc == 5) {
                laddr1 = addr1 = argv[1];
                port1 = argv[2];
                faddr2 = addr2 = argv[3];
                port2 = argv[4];
-       } else {
-fail:
-               fprintf(stderr,
-                   "usage: %s local-addr local-port remote-addr remote-port\n",
-                   __progname);
-               fprintf(stderr,
-                   "       %s local-addr:local-port remote-addr:remote-port\n",
-                   __progname);
-               exit(1);
-       }
+       } else
+               usage();
 
        if (addr1[0] == '[' && addr1[strlen(addr1) - 1] == ']') {
                laddr1 = strdup(addr1);