LXR busybox/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 "common.h"
   6#include "dhcpd.h"
   7#include "unicode.h"
   8
   9#if BB_LITTLE_ENDIAN
  10static inline uint64_t hton64(uint64_t v)
  11{
  12        return (((uint64_t)htonl(v)) << 32) | htonl(v >> 32);
  13}
  14#else
  15#define hton64(v) (v)
  16#endif
  17#define ntoh64(v) hton64(v)
  18
  19
  20int dumpleases_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  21int dumpleases_main(int argc UNUSED_PARAM, char **argv)
  22{
  23        int fd;
  24        int i;
  25        unsigned opt;
  26        int64_t written_at, curr, expires_abs;
  27        const char *file = LEASES_FILE;
  28        struct dyn_lease lease;
  29        struct in_addr addr;
  30
  31        enum {
  32                OPT_a   = 0x1,  // -a
  33                OPT_r   = 0x2,  // -r
  34                OPT_f   = 0x4,  // -f
  35        };
  36#if ENABLE_LONG_OPTS
  37        static const char dumpleases_longopts[] ALIGN1 =
  38                "absolute\0"  No_argument       "a"
  39                "remaining\0" No_argument       "r"
  40                "file\0"      Required_argument "f"
  41                ;
  42
  43        applet_long_options = dumpleases_longopts;
  44#endif
  45        init_unicode();
  46
  47        opt_complementary = "=0:a--r:r--a";
  48        opt = getopt32(argv, "arf:", &file);
  49
  50        fd = xopen(file, O_RDONLY);
  51
  52        printf("Mac Address       IP Address      Host Name           Expires %s\n", (opt & OPT_a) ? "at" : "in");
  53        /*     "00:00:00:00:00:00 255.255.255.255 ABCDEFGHIJKLMNOPQRS Wed Jun 30 21:49:08 1993" */
  54        /*     "123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789 */
  55
  56        xread(fd, &written_at, sizeof(written_at));
  57        written_at = ntoh64(written_at);
  58        curr = time(NULL);
  59        if (curr < written_at)
  60                written_at = curr; /* lease file from future! :) */
  61
  62        while (full_read(fd, &lease, sizeof(lease)) == sizeof(lease)) {
  63                const char *fmt = ":%02x" + 1;
  64                for (i = 0; i < 6; i++) {
  65                        printf(fmt, lease.lease_mac[i]);
  66                        fmt = ":%02x";
  67                }
  68                addr.s_addr = lease.lease_nip;
  69#if ENABLE_UNICODE_SUPPORT
  70                {
  71                        char *uni_name = unicode_conv_to_printable_fixedwidth(NULL, lease.hostname, 19);
  72                        printf(" %-16s%s ", inet_ntoa(addr), uni_name);
  73                        free(uni_name);
  74                }
  75#else
  76                /* actually, 15+1 and 19+1, +1 is a space between columns */
  77                /* lease.hostname is char[20] and is always NUL terminated */
  78                printf(" %-16s%-20s", inet_ntoa(addr), lease.hostname);
  79#endif
  80                expires_abs = ntohl(lease.expires) + written_at;
  81                if (expires_abs <= curr) {
  82                        puts("expired");
  83                        continue;
  84                }
  85                if (!(opt & OPT_a)) { /* no -a */
  86                        unsigned d, h, m;
  87                        unsigned expires = expires_abs - curr;
  88                        d = expires / (24*60*60); expires %= (24*60*60);
  89                        h = expires / (60*60); expires %= (60*60);
  90                        m = expires / 60; expires %= 60;
  91                        if (d)
  92                                printf("%u days ", d);
  93                        printf("%02u:%02u:%02u\n", h, m, (unsigned)expires);
  94                } else { /* -a */
  95                        time_t t = expires_abs;
  96                        fputs(ctime(&t), stdout);
  97                }
  98        }
  99        /* close(fd); */
 100
 101        return 0;
 102}
 103