networking/udhcp/dumpleases.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
   4  */
   5 #include <getopt.h>
   6
   7 #include "common.h"
   8 #include "dhcpd.h"
   9
  10
  11 #define REMAINING 0
  12 #define ABSOLUTE 1
  13
  14 int dumpleases_main(int argc, char *argv[])
  15 {
  16         int fp;
  17         int i, c, mode = REMAINING;
  18         unsigned long expires;
  19         const char *file = LEASES_FILE;
  20         struct dhcpOfferedAddr lease;
  21         struct in_addr addr;
  22
  23         static const struct option options[] = {
  24                 {"absolute", 0, 0, 'a'},
  25                 {"remaining", 0, 0, 'r'},
  26                 {"file", 1, 0, 'f'},
  27                 {0, 0, 0, 0}
  28         };
  29
  30         while (1) {
  31                 int option_index = 0;
  32                 c = getopt_long(argc, argv, "arf:", options, &option_index);
  33                 if (c == -1) break;
  34
  35                 switch (c) {
  36                 case 'a': mode = ABSOLUTE; break;
  37                 case 'r': mode = REMAINING; break;
  38                 case 'f':
  39                         file = optarg;
  40                         break;
  41                 default:
  42                         bb_show_usage();
  43                 }
  44         }
  45
  46         fp = xopen(file, O_RDONLY);
  47
  48         printf("Mac Address       IP-Address      Expires %s\n", mode == REMAINING ? "in" : "at");
  49         /*     "00:00:00:00:00:00 255.255.255.255 Wed Jun 30 21:49:08 1993" */
  50         while (full_read(fp, &lease, sizeof(lease)) == sizeof(lease)) {
  51                 printf(":%02x"+1, lease.chaddr[0]);
  52                 for (i = 1; i < 6; i++) {
  53                         printf(":%02x", lease.chaddr[i]);
  54                 }
  55                 addr.s_addr = lease.yiaddr;
  56                 printf(" %-15s ", inet_ntoa(addr));
  57                 expires = ntohl(lease.expires);
  58                 if (mode == REMAINING) {
  59                         if (!expires)
  60                                 printf("expired\n");
  61                         else {
  62                                 unsigned d, h, m;
  63                                 d = expires / (24*60*60); expires %= (24*60*60);
  64                                 h = expires / (60*60); expires %= (60*60);
  65                                 m = expires / 60; expires %= 60;
  66                                 if (d) printf("%u days ", d);
  67                                 printf("%02u:%02u:%02u\n", h, m, (unsigned)expires);
  68                         }
  69                 } else fputs(ctime(&expires), stdout);
  70         }
  71         /* close(fp); */
  72
  73         return 0;
  74 }