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/* vi: set sw=4 ts=4: */
/*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
#include "common.h"
#include "dhcpd.h"
#if BB_LITTLE_ENDIAN
static inline uint64_t hton64(uint64_t v)
{
return (((uint64_t)htonl(v)) << 32) | htonl(v >> 32);
}
#else
#define hton64(v) (v)
#endif
#define ntoh64(v) hton64(v)
int dumpleases_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int dumpleases_main(int argc UNUSED_PARAM, char **argv)
{
int fd;
int i;
unsigned opt;
int64_t written_at, curr, expires_abs;
const char *file = LEASES_FILE;
struct dhcpOfferedAddr lease;
struct in_addr addr;
enum {
OPT_a = 0x1, // -a
OPT_r = 0x2, // -r
OPT_f = 0x4, // -f
};
#if ENABLE_GETOPT_LONG
static const char dumpleases_longopts[] ALIGN1 =
"absolute\0" No_argument "a"
"remaining\0" No_argument "r"
"file\0" Required_argument "f"
;
applet_long_options = dumpleases_longopts;
#endif
opt_complementary = "=0:a--r:r--a";
opt = getopt32(argv, "arf:", &file);
fd = xopen(file, O_RDONLY);
printf("Mac Address IP Address Host Name Expires %s\n", (opt & OPT_a) ? "at" : "in");
/* "00:00:00:00:00:00 255.255.255.255 ABCDEFGHIJKLMNOPQRS Wed Jun 30 21:49:08 1993" */
/* "123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789 */
if (full_read(fd, &written_at, sizeof(written_at)) != sizeof(written_at))
return 0;
written_at = ntoh64(written_at);
curr = time(NULL);
if (curr < written_at)
written_at = curr; /* lease file from future! :) */
while (full_read(fd, &lease, sizeof(lease)) == sizeof(lease)) {
const char *fmt = ":%02x" + 1;
for (i = 0; i < 6; i++) {
printf(fmt, lease.chaddr[i]);
fmt = ":%02x";
}
addr.s_addr = lease.yiaddr;
/* actually, 15+1 and 19+1, +1 is a space between columns */
/* lease.hostname is char[20] and is always NUL terminated */
printf(" %-16s%-20s", inet_ntoa(addr), lease.hostname);
expires_abs = ntohl(lease.expires) + written_at;
if (expires_abs <= curr) {
puts("expired");
continue;
}
if (!(opt & OPT_a)) { /* no -a */
unsigned d, h, m;
unsigned expires = expires_abs - curr;
d = expires / (24*60*60); expires %= (24*60*60);
h = expires / (60*60); expires %= (60*60);
m = expires / 60; expires %= 60;
if (d)
printf("%u days ", d);
printf("%02u:%02u:%02u\n", h, m, (unsigned)expires);
} else { /* -a */
time_t t = expires_abs;
fputs(ctime(&t), stdout);
}
}
/* close(fd); */
return 0;
}
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