/* SPDX-License-Identifier: LGPL-2.1-or-later
 * Copyright © 2020 VMware, Inc. */

#include <linux/pkt_sched.h>

#include "alloc-util.h"
#include "conf-parser.h"
#include "fifo.h"
#include "netlink-util.h"
#include "parse-util.h"
#include "string-util.h"

static int fifo_fill_message(Link *link, QDisc *qdisc, sd_netlink_message *req) {
        struct tc_fifo_qopt opt = {};
        FirstInFirstOut *fifo;
        int r;

        assert(link);
        assert(qdisc);
        assert(req);

        switch(qdisc->kind) {
        case QDISC_KIND_PFIFO:
                fifo = PFIFO(qdisc);
                break;
        case QDISC_KIND_BFIFO:
                fifo = BFIFO(qdisc);
                break;
        case QDISC_KIND_PFIFO_HEAD_DROP:
                fifo = PFIFO_HEAD_DROP(qdisc);
                break;
        default:
                assert_not_reached("Invalid QDisc kind.");
        }

        opt.limit = fifo->limit;

        r = sd_netlink_message_append_data(req, TCA_OPTIONS, &opt, sizeof(struct tc_fifo_qopt));
        if (r < 0)
                return log_link_error_errno(link, r, "Could not append TCA_OPTIONS attribute: %m");

        return 0;
}

int config_parse_pfifo_size(
                const char *unit,
                const char *filename,
                unsigned line,
                const char *section,
                unsigned section_line,
                const char *lvalue,
                int ltype,
                const char *rvalue,
                void *data,
                void *userdata) {

        _cleanup_(qdisc_free_or_set_invalidp) QDisc *qdisc = NULL;
        Network *network = data;
        FirstInFirstOut *fifo;
        int r;

        assert(filename);
        assert(lvalue);
        assert(rvalue);
        assert(data);

        r = qdisc_new_static(ltype, network, filename, section_line, &qdisc);
        if (r == -ENOMEM)
                return log_oom();
        if (r < 0) {
                log_syntax(unit, LOG_WARNING, filename, line, r,
                           "More than one kind of queueing discipline, ignoring assignment: %m");
                return 0;
        }

        switch(qdisc->kind) {
        case QDISC_KIND_PFIFO:
                fifo = PFIFO(qdisc);
                break;
        case QDISC_KIND_PFIFO_HEAD_DROP:
                fifo = PFIFO_HEAD_DROP(qdisc);
                break;
        default:
                assert_not_reached("Invalid QDisc kind.");
        }

        if (isempty(rvalue)) {
                fifo->limit = 0;

                qdisc = NULL;
                return 0;
        }

        r = safe_atou32(rvalue, &fifo->limit);
        if (r < 0) {
                log_syntax(unit, LOG_WARNING, filename, line, r,
                           "Failed to parse '%s=', ignoring assignment: %s",
                           lvalue, rvalue);
                return 0;
        }

        qdisc = NULL;
        return 0;
}

int config_parse_bfifo_size(
                const char *unit,
                const char *filename,
                unsigned line,
                const char *section,
                unsigned section_line,
                const char *lvalue,
                int ltype,
                const char *rvalue,
                void *data,
                void *userdata) {

        _cleanup_(qdisc_free_or_set_invalidp) QDisc *qdisc = NULL;
        Network *network = data;
        FirstInFirstOut *fifo;
        uint64_t u;
        int r;

        assert(filename);
        assert(lvalue);
        assert(rvalue);
        assert(data);

        r = qdisc_new_static(QDISC_KIND_BFIFO, network, filename, section_line, &qdisc);
        if (r == -ENOMEM)
                return log_oom();
        if (r < 0) {
                log_syntax(unit, LOG_WARNING, filename, line, r,
                           "More than one kind of queueing discipline, ignoring assignment: %m");
                return 0;
        }

        fifo = BFIFO(qdisc);

        if (isempty(rvalue)) {
                fifo->limit = 0;

                qdisc = NULL;
                return 0;
        }

        r = parse_size(rvalue, 1024, &u);
        if (r < 0) {
                log_syntax(unit, LOG_WARNING, filename, line, r,
                           "Failed to parse '%s=', ignoring assignment: %s",
                           lvalue, rvalue);
                return 0;
        }
        if (u > UINT32_MAX) {
                log_syntax(unit, LOG_WARNING, filename, line, 0, "Invalid '%s=', ignoring assignment: %s",
                           lvalue, rvalue);
                return 0;
        }

        fifo->limit = (uint32_t) u;

        qdisc = NULL;
        return 0;
}

const QDiscVTable pfifo_vtable = {
        .object_size = sizeof(FirstInFirstOut),
        .tca_kind = "pfifo",
        .fill_message = fifo_fill_message,
};

const QDiscVTable bfifo_vtable = {
       .object_size = sizeof(FirstInFirstOut),
       .tca_kind = "bfifo",
       .fill_message = fifo_fill_message,
};

const QDiscVTable pfifo_head_drop_vtable = {
       .object_size = sizeof(FirstInFirstOut),
       .tca_kind = "pfifo_head_drop",
       .fill_message = fifo_fill_message,
};

const QDiscVTable pfifo_fast_vtable = {
       .object_size = sizeof(FirstInFirstOut),
       .tca_kind = "pfifo_fast",
};