/* Copyright (C) 2013 Cisco Systems, Inc, 2013.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * Author: Vijay Subramanian <vijaynsu@cisco.com>

 * Author: Mythili Prabhu <mysuryan@cisco.com>

 *

 */

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <fcntl.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <arpa/inet.h>

#include <string.h>

#include <math.h>

#include "utils.h"

#include "tc_util.h"

static void explain(void)

{

	fprintf(stderr,

		"Usage: ... pie	[ limit PACKETS ][ target TIME us]\n"

		"		[ tupdate TIME us][ alpha ALPHA ]"

		"[beta BETA ][bytemode | nobytemode][ecn | noecn ]\n");

}

#define ALPHA_MAX 32

#define BETA_MAX 32

static int pie_parse_opt(struct qdisc_util *qu, int argc, char **argv,

			 struct nlmsghdr *n, const char *dev)

{

	unsigned int limit   = 0;

	unsigned int target  = 0;

	unsigned int tupdate = 0;

	unsigned int alpha   = 0;

	unsigned int beta    = 0;

	int ecn = -1;

	int bytemode = -1;

	struct rtattr *tail;

	while (argc > 0) {

		if (strcmp(*argv, "limit") == 0) {

			NEXT_ARG();

			if (get_unsigned(&limit, *argv, 0)) {

				fprintf(stderr, "Illegal \"limit\"\n");

				return -1;

			}

		} else if (strcmp(*argv, "target") == 0) {

			NEXT_ARG();

			if (get_time(&target, *argv)) {

				fprintf(stderr, "Illegal \"target\"\n");

				return -1;

			}

		} else if (strcmp(*argv, "tupdate") == 0) {

			NEXT_ARG();

			if (get_time(&tupdate, *argv)) {

				fprintf(stderr, "Illegal \"tupdate\"\n");

				return -1;

			}

		} else if (strcmp(*argv, "alpha") == 0) {

			NEXT_ARG();

			if (get_unsigned(&alpha, *argv, 0) ||

			    (alpha > ALPHA_MAX)) {

				fprintf(stderr, "Illegal \"alpha\"\n");

				return -1;

			}

		} else if (strcmp(*argv, "beta") == 0) {

			NEXT_ARG();

			if (get_unsigned(&beta, *argv, 0) ||

			    (beta > BETA_MAX)) {

				fprintf(stderr, "Illegal \"beta\"\n");

				return -1;

			}

		} else if (strcmp(*argv, "ecn") == 0) {

			ecn = 1;

		} else if (strcmp(*argv, "noecn") == 0) {

			ecn = 0;

		} else if (strcmp(*argv, "bytemode") == 0) {

			bytemode = 1;

		} else if (strcmp(*argv, "nobytemode") == 0) {

			bytemode = 0;

		} else if (strcmp(*argv, "help") == 0) {

			explain();

			return -1;

		} else {

			fprintf(stderr, "What is \"%s\"?\n", *argv);

			explain();

			return -1;

		}

		argc--;

		argv++;

	}

	tail = addattr_nest(n, 1024, TCA_OPTIONS);

	if (limit)

		addattr_l(n, 1024, TCA_PIE_LIMIT, &limit, sizeof(limit));

	if (tupdate)

		addattr_l(n, 1024, TCA_PIE_TUPDATE, &tupdate, sizeof(tupdate));

	if (target)

		addattr_l(n, 1024, TCA_PIE_TARGET, &target, sizeof(target));

	if (alpha)

		addattr_l(n, 1024, TCA_PIE_ALPHA, &alpha, sizeof(alpha));

	if (beta)

		addattr_l(n, 1024, TCA_PIE_BETA, &beta, sizeof(beta));

	if (ecn != -1)

		addattr_l(n, 1024, TCA_PIE_ECN, &ecn, sizeof(ecn));

	if (bytemode != -1)

		addattr_l(n, 1024, TCA_PIE_BYTEMODE, &bytemode,

			  sizeof(bytemode));

	addattr_nest_end(n, tail);

	return 0;

}

static int pie_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)

{

	struct rtattr *tb[TCA_PIE_MAX + 1];

	unsigned int limit;

	unsigned int tupdate;

	unsigned int target;

	unsigned int alpha;

	unsigned int beta;

	unsigned int ecn;

	unsigned int bytemode;

	SPRINT_BUF(b1);

	if (opt == NULL)

		return 0;

	parse_rtattr_nested(tb, TCA_PIE_MAX, opt);

	if (tb[TCA_PIE_LIMIT] &&

	    RTA_PAYLOAD(tb[TCA_PIE_LIMIT]) >= sizeof(__u32)) {

		limit = rta_getattr_u32(tb[TCA_PIE_LIMIT]);

		fprintf(f, "limit %up ", limit);

	}

	if (tb[TCA_PIE_TARGET] &&

	    RTA_PAYLOAD(tb[TCA_PIE_TARGET]) >= sizeof(__u32)) {

		target = rta_getattr_u32(tb[TCA_PIE_TARGET]);

		fprintf(f, "target %s ", sprint_time(target, b1));

	}

	if (tb[TCA_PIE_TUPDATE] &&

	    RTA_PAYLOAD(tb[TCA_PIE_TUPDATE]) >= sizeof(__u32)) {

		tupdate = rta_getattr_u32(tb[TCA_PIE_TUPDATE]);

		fprintf(f, "tupdate %s ", sprint_time(tupdate, b1));

	}

	if (tb[TCA_PIE_ALPHA] &&

	    RTA_PAYLOAD(tb[TCA_PIE_ALPHA]) >= sizeof(__u32)) {

		alpha = rta_getattr_u32(tb[TCA_PIE_ALPHA]);

		fprintf(f, "alpha %u ", alpha);

	}

	if (tb[TCA_PIE_BETA] &&

	    RTA_PAYLOAD(tb[TCA_PIE_BETA]) >= sizeof(__u32)) {

		beta = rta_getattr_u32(tb[TCA_PIE_BETA]);

		fprintf(f, "beta %u ", beta);

	}

	if (tb[TCA_PIE_ECN] && RTA_PAYLOAD(tb[TCA_PIE_ECN]) >= sizeof(__u32)) {

		ecn = rta_getattr_u32(tb[TCA_PIE_ECN]);

		if (ecn)

			fprintf(f, "ecn ");

	}

	if (tb[TCA_PIE_BYTEMODE] &&

	    RTA_PAYLOAD(tb[TCA_PIE_BYTEMODE]) >= sizeof(__u32)) {

		bytemode = rta_getattr_u32(tb[TCA_PIE_BYTEMODE]);

		if (bytemode)

			fprintf(f, "bytemode ");

	}

	return 0;

}

static int pie_print_xstats(struct qdisc_util *qu, FILE *f,

			    struct rtattr *xstats)

{

	struct tc_pie_xstats *st;

	if (xstats == NULL)

		return 0;

	if (RTA_PAYLOAD(xstats) < sizeof(*st))

		return -1;

	st = RTA_DATA(xstats);

	/*prob is returned as a fracion of maximum integer value */

	fprintf(f, "prob %f delay %uus avg_dq_rate %u\n",

		(double)st->prob / UINT64_MAX, st->delay,

		st->avg_dq_rate);

	fprintf(f, "pkts_in %u overlimit %u dropped %u maxq %u ecn_mark %u\n",

		st->packets_in, st->overlimit, st->dropped, st->maxq,

		st->ecn_mark);

	return 0;

}

struct qdisc_util pie_qdisc_util = {

	.id = "pie",

	.parse_qopt	= pie_parse_opt,

	.print_qopt	= pie_print_opt,

	.print_xstats	= pie_print_xstats,

};