hush/networking/udhcp/dumpleases.c

/* vi: set sw=4 ts=4: */
/*
 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
 */
#include <getopt.h>

#include "common.h"
#include "dhcpd.h"


#define REMAINING 0
#define ABSOLUTE 1

int dumpleases_main(int argc, char *argv[]);
int dumpleases_main(int argc, char *argv[])
{
	int fp;
	int i, c, mode = REMAINING;
	unsigned long expires;
	const char *file = LEASES_FILE;
	struct dhcpOfferedAddr lease;
	struct in_addr addr;

	static const struct option options[] = {
		{"absolute", 0, 0, 'a'},
		{"remaining", 0, 0, 'r'},
		{"file", 1, 0, 'f'},
		{0, 0, 0, 0}
	};

	while (1) {
		int option_index = 0;
		c = getopt_long(argc, argv, "arf:", options, &option_index);
		if (c == -1) break;

		switch (c) {
		case 'a': mode = ABSOLUTE; break;
		case 'r': mode = REMAINING; break;
		case 'f':
			file = optarg;
			break;
		default:
			bb_show_usage();
		}
	}

	fp = xopen(file, O_RDONLY);

	printf("Mac Address       IP-Address      Expires %s\n", mode == REMAINING ? "in" : "at");
	/*     "00:00:00:00:00:00 255.255.255.255 Wed Jun 30 21:49:08 1993" */
	while (full_read(fp, &lease, sizeof(lease)) == sizeof(lease)) {
		printf(":%02x"+1, lease.chaddr[0]);
		for (i = 1; i < 6; i++) {
			printf(":%02x", lease.chaddr[i]);
		}
		addr.s_addr = lease.yiaddr;
		printf(" %-15s ", inet_ntoa(addr));
		expires = ntohl(lease.expires);
		if (mode == REMAINING) {
			if (!expires)
				printf("expired\n");
			else {
				unsigned d, h, m;
				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 fputs(ctime(&expires), stdout);
	}
	/* close(fp); */

	return 0;
}