Use __progname rather than argv[0]; OK millert@

diff --git a/usr.bin/skey/skey.c b/usr.bin/skey/skey.c
index 313fcb9..373da3d 100644 (file)
--- a/usr.bin/skey/skey.c
+++ b/usr.bin/skey/skey.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: skey.c,v 1.29 2015/10/09 20:14:35 tim Exp $   */
+/*     $OpenBSD: skey.c,v 1.30 2015/10/09 20:24:37 tim Exp $   */
 /*
  * OpenBSD S/Key (skey.c)
  *
@@ -31,25 +31,23 @@
 #include <readpassphrase.h>
 #include <skey.h>
 
-void    usage(char *);
+void usage();
+
+extern char *__progname;
 
 int
 main(int argc, char *argv[])
 {
        int     n, i, cnt = 1, pass = 0, hexmode = 0;
        char    passwd[SKEY_MAX_PW_LEN+1], key[SKEY_BINKEY_SIZE];
-       char    buf[33], *seed, *slash;
+       char    buf[33], *seed, *slash, *algo;
        const char *errstr;
 
        /* If we were called as otp-METHOD, set algorithm based on that */
-       if ((slash = strrchr(argv[0], '/')))
-               slash++;
-       else
-               slash = argv[0];
-       if (strncmp(slash, "otp-", 4) == 0) {
-               slash += 4;
-               if (skey_set_algorithm(slash) == NULL)
-                       errx(1, "Unknown hash algorithm %s", slash);
+       if (strncmp(__progname, "otp-", 4) == 0) {
+               algo = __progname + 4;
+               if (skey_set_algorithm(algo) == NULL)
+                       errx(1, "Unknown hash algorithm %s", algo);
        }
 
        for (i = 1; i < argc && argv[i][0] == '-' && strcmp(argv[i], "--");) {
@@ -58,14 +56,14 @@ main(int argc, char *argv[])
                        switch (argv[i][1]) {
                        case 'n':
                                if (++i == argc)
-                                       usage(argv[0]);
+                                       usage();
                                cnt = strtonum(argv[i], 1, SKEY_MAX_SEQ -1, &errstr);
                                if (errstr)
-                                       usage(argv[0]);
+                                       usage();
                                break;
                        case 'p':
                                if (++i == argc)
-                                       usage(argv[0]);
+                                       usage();
                                if (strlcpy(passwd, argv[i], sizeof(passwd)) >=
                                    sizeof(passwd))
                                        errx(1, "Password too long");
@@ -75,42 +73,42 @@ main(int argc, char *argv[])
                                hexmode = 1;
                                break;
                        default:
-                               usage(argv[0]);
+                               usage();
                        }
                } else {
                        /* Multi character switches are hash types */
                        if (skey_set_algorithm(&argv[i][1]) == NULL) {
                                warnx("Unknown hash algorithm %s", &argv[i][1]);
-                               usage(argv[0]);
+                               usage();
                        }
                }
                i++;
        }
 
        if (argc > i + 2)
-               usage(argv[0]);
+               usage();
 
        /* Could be in the form <number>/<seed> */
        if (argc <= i + 1) {
                /* look for / in it */
                if (argc <= i)
-                       usage(argv[0]);
+                       usage();
                slash = strchr(argv[i], '/');
                if (slash == NULL)
-                       usage(argv[0]);
+                       usage();
                *slash++ = '\0';
                seed = slash;
 
                n = strtonum(argv[i], 0, SKEY_MAX_SEQ, &errstr);
                if (errstr) {
                        warnx("%s: %s", argv[i], errstr);
-                       usage(argv[0]);
+                       usage();
                }
        } else {
                n = strtonum(argv[i], 0, SKEY_MAX_SEQ, &errstr);
                if (errstr) {
                        warnx("%s: %s", argv[i], errstr);
-                       usage(argv[0]);
+                       usage();
                }
                seed = argv[++i];
        }
@@ -147,10 +145,10 @@ main(int argc, char *argv[])
 }
 
 void
-usage(char *s)
+usage(void)
 {
        fprintf(stderr,
            "usage: %s [-x] [-md5 | -rmd160 | -sha1] [-n count]\n\t"
-           "[-p passphrase] <sequence#>[/] key\n", s);
+           "[-p passphrase] <sequence#>[/] key\n", __progname);
        exit(1);
 }