src/oping.c: Exit successfully when using the -h option.

[liboping.git] / src / oping.c

diff --git a/src/oping.c b/src/oping.c
index 3164230..a1dbade 100644 (file)
--- a/src/oping.c
+++ b/src/oping.c
@@ -107,19 +107,28 @@ static void context_destroy (ping_context_t *context)
        free (context);
 }
 
-static void usage_exit (const char *name)
+static void usage_exit (const char *name, int status)
 {
        int name_length;
 
        name_length = (int) strlen (name);
 
-       fprintf (stderr, "Usage: %s [-46] [-c count] [-i interval]\n"
-                       "%*s[-t ttl] [-I srcaddr]\n"
-                       "%*s-f filename | host [host [host ...]]\n",
-                       name,
-                       8 + name_length, "",
-                       8 + name_length, "");
-       exit (1);
+       fprintf (stderr, "Usage: %s [OPTIONS] "
+                               "-f filename | host [host [host ...]]\n"
+
+                       "\nAvailable options:\n"
+                       "  -4|-6        force the use of IPv4 or IPv6\n"
+                       "  -c count     number of ICMP packets to send\n"
+                       "  -i interval  interval with which to send ICMP packets\n"
+                       "  -t ttl       time to live for each ICMP packet\n"
+                       "  -I srcaddr   source address\n"
+                       "  -f filename  filename to read hosts from\n"
+
+                       "\noping "PACKAGE_VERSION", http://verplant.org/liboping/\n"
+                       "by Florian octo Forster <octo@verplant.org>\n"
+                       "for contributions see `AUTHORS'\n",
+                       name);
+       exit (status);
 }
 
 static int read_options (int argc, char **argv)
@@ -146,6 +155,9 @@ static int read_options (int argc, char **argv)
                                        new_count = atoi (optarg);
                                        if (new_count > 0)
                                                opt_count = new_count;
+                                       else
+                                               fprintf(stderr, "Ignoring invalid count: %s\n",
+                                                               optarg);
                                }
                                break;
 
@@ -162,8 +174,8 @@ static int read_options (int argc, char **argv)
                                        double new_interval;
                                        new_interval = atof (optarg);
                                        if (new_interval < 0.001)
-                                               fprintf (stderr, "Ignoring invalid interval %g.\n",
-                                                               new_interval);
+                                               fprintf (stderr, "Ignoring invalid interval: %s\n",
+                                                               optarg);
                                        else
                                                opt_interval = new_interval;
                                }
@@ -183,14 +195,16 @@ static int read_options (int argc, char **argv)
                                if ((new_send_ttl > 0) && (new_send_ttl < 256))
                                        opt_send_ttl = new_send_ttl;
                                else
-                                       fprintf (stderr, "Invalid TTL argument: %s\n",
+                                       fprintf (stderr, "Ignoring invalid TTL argument: %s\n",
                                                        optarg);
                                break;
                        }
 
                        case 'h':
+                               usage_exit (argv[0], 0);
+                               break;
                        default:
-                               usage_exit (argv[0]);
+                               usage_exit (argv[0], 1);
                }
        }
 
@@ -316,8 +330,8 @@ int main (int argc, char **argv)
 
        optind = read_options (argc, argv);
 
-       if (optind >= argc && !opt_filename) {
-               usage_exit (argv[0]);
+       if ((optind >= argc) && (opt_filename == NULL)) {
+               usage_exit (argv[0], 1);
        }
 
        if (geteuid () != 0)
@@ -367,23 +381,28 @@ int main (int argc, char **argv)
                char line[256];
                char host[256];
 
-               if (strncmp(opt_filename, "-", 1) == 0)
+               if (strcmp (opt_filename, "-") == 0)
+                       /* Open STDIN */
                        infile = fdopen(0, "r");
                else
                        infile = fopen(opt_filename, "r");
 
-               if (!infile)
+               if (infile == NULL)
                {
-                       fprintf (stderr, "Couldn't open file for hostnames: %s\n", strerror(errno));
+                       fprintf (stderr, "Opening %s failed: %s\n",
+                                       (strcmp (opt_filename, "-") == 0)
+                                       ? "STDIN" : opt_filename,
+                                       strerror(errno));
                        return (1);
                }
 
                while (fgets(line, sizeof(line), infile))
                {
+                       /* Strip whitespace */
                        if (sscanf(line, "%s", host) != 1)
                                continue;
 
-                       if ((!*host) || (host[0] == '#'))
+                       if ((host[0] == 0) || (host[0] == '#'))
                                continue;
 
                        if (ping_host_add(ping, host) < 0)