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/* vi: set sw=4 ts=4: */
/*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//applet:IF_DUMPLEASES(APPLET_NOEXEC(dumpleases, dumpleases, BB_DIR_USR_BIN, BB_SUID_DROP, dumpleases))
//kbuild:lib-$(CONFIG_DUMPLEASES) += dumpleases.o
//usage:#define dumpleases_trivial_usage
//usage: "[-r|-a] [-d] [-f LEASEFILE]"
//usage:#define dumpleases_full_usage "\n\n"
//usage: "Display DHCP leases granted by udhcpd\n"
//usage: "\n -f FILE Lease file"
//usage: "\n -r Show remaining time"
//usage: "\n -a Show expiration time"
//usage: "\n -d Show time in seconds"
#include "common.h"
#include "dhcpd.h"
#include "unicode.h"
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;
const char *file = LEASES_FILE;
struct dyn_lease lease;
enum {
OPT_a = 0x1, // -a
OPT_r = 0x2, // -r
OPT_f = 0x4, // -f
OPT_d = 0x8, // -d
};
#if ENABLE_LONG_OPTS
static const char dumpleases_longopts[] ALIGN1 =
"absolute\0" No_argument "a"
"remaining\0" No_argument "r"
"file\0" Required_argument "f"
"decimal\0" No_argument "d"
;
#endif
init_unicode();
opt = getopt32long(argv, "^"
"arf:d"
"\0" "=0:a--r:r--a",
dumpleases_longopts,
&file
);
fd = xopen(file, O_RDONLY);
/* "123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789 */
/* "00:00:00:00:00:00 255.255.255.255 ABCDEFGHIJKLMNOPQRS Wed Jun 30 21:49:08 1993" */
printf("Mac %-14s" "IP %-13s" "Host %-15s" "Expires %s\n",
"Address", "Address", "Name",
(opt & OPT_a) ? "at" : "in"
);
xread(fd, &written_at, sizeof(written_at));
written_at = SWAP_BE64(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)) {
struct in_addr addr;
int64_t expires_abs;
const char *fmt = ":%02x" + 1;
for (i = 0; i < 6; i++) {
printf(fmt, lease.lease_mac[i]);
fmt = ":%02x";
}
addr.s_addr = lease.lease_nip;
#if ENABLE_UNICODE_SUPPORT
{
char *uni_name = unicode_conv_to_printable_fixedwidth(/*NULL,*/ lease.hostname, 19);
printf(" %-16s%s ", inet_ntoa(addr), uni_name);
free(uni_name);
}
#else
/* 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);
#endif
expires_abs = ntohl(lease.expires) + written_at;
if (expires_abs <= curr) {
puts("expired");
continue;
}
if (opt & OPT_d) {
/* -d: decimal time */
if (!(opt & OPT_a))
expires_abs -= curr;
printf("%llu\n", (unsigned long long) expires_abs);
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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