/*
 *  Empire - A multi-player, client/server Internet based war game.
 *  Copyright (C) 1986-2021, Dave Pare, Jeff Bailey, Thomas Ruschak,
 *                Ken Stevens, Steve McClure, Markus Armbruster
 *
 *  Empire 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 3 of the License, or
 *  (at your option) any later version.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *  ---
 *
 *  See files README, COPYING and CREDITS in the root of the source
 *  tree for related information and legal notices.  It is expected
 *  that future projects/authors will amend these files as needed.
 *
 *  ---
 *
 *  aswplnsubs.c: Various subroutines used for ASW planes
 *
 *  Known contributors to this file:
 *     Ron Koenderink, 2004
 */

#include <config.h>

#include "misc.h"
#include "plane.h"
#include "prototypes.h"

int
on_shiplist(int uid, struct shiplist *head)
{
    struct shiplist *s;

    s = head;
    while (s != NULL) {
	if (s->uid == uid)
	    return 1;
	s = s->next;
    }
    return 0;
}

void
add_shiplist(int uid, struct shiplist **head)
{
    struct shiplist *s, *s2;

    s = *head;
    s2 = NULL;

    while (s != NULL) {
	if (s->uid == uid) {
	    return;
	}
	s2 = s;
	s = s->next;
    }

    s = malloc(sizeof(struct shiplist));
    if (s2 != NULL)
	s2->next = s;
    else
	*head = s;
    s->uid = uid;
    s->next = NULL;
}

void
free_shiplist(struct shiplist **head)
{
    struct shiplist *s, *s2;

    s = *head;

    while (s != NULL) {
	s2 = s;
	s = s->next;
	free(s2);
    }
    *head = NULL;
}
