xref: /openbsd/games/sail/misc.c (revision df69c215)
1 /*	$OpenBSD: misc.c,v 1.11 2019/06/28 13:32:52 deraadt Exp $	*/
2 /*	$NetBSD: misc.c,v 1.3 1995/04/22 10:37:03 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1983, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <ctype.h>
34 #include <err.h>
35 #ifdef LOCK_EX
36 #include <fcntl.h>
37 #endif
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <unistd.h>
42 
43 #include "extern.h"
44 #include "pathnames.h"
45 
46 #define distance(x,y) (abs(x) >= abs(y) ? abs(x) + abs(y)/2 : abs(y) + abs(x)/2)
47 
48 /* XXX */
49 int
range(struct ship * from,struct ship * to)50 range(struct ship *from, struct ship *to)
51 {
52 	int bow1r, bow1c, bow2r, bow2c;
53 	int stern1r, stern1c, stern2c, stern2r;
54 	int bb, bs, sb, ss, result;
55 
56 	if (!to->file->dir)
57 		return -1;
58 	stern1r = bow1r = from->file->row;
59 	stern1c = bow1c = from->file->col;
60 	stern2r = bow2r = to->file->row;
61 	stern2c = bow2c = to->file->col;
62 	result = bb = distance(bow2r - bow1r, bow2c - bow1c);
63 	if (bb < 5) {
64 		stern2r += dr[to->file->dir];
65 		stern2c += dc[to->file->dir];
66 		stern1r += dr[from->file->dir];
67 		stern1c += dc[from->file->dir];
68 		bs = distance((bow2r - stern1r), (bow2c - stern1c));
69 		sb = distance((bow1r - stern2r), (bow1c - stern2c));
70 		ss = distance((stern2r - stern1r) ,(stern2c - stern1c));
71 		result = min(bb, min(bs, min(sb, ss)));
72 	}
73 	return result;
74 }
75 
76 struct ship *
closestenemy(struct ship * from,int side,int anyship)77 closestenemy(struct ship *from, int side, int anyship)
78 {
79 	struct ship *sp;
80 	char a;
81 	int olddist = 30000, dist;
82 	struct ship *closest = 0;
83 
84 	a = capship(from)->nationality;
85 	foreachship(sp) {
86 		if (sp == from)
87 			continue;
88 		if (sp->file->dir == 0)
89 			continue;
90 		if (a == capship(sp)->nationality && !anyship)
91 			continue;
92 		if (side && gunsbear(from, sp) != side)
93 			continue;
94 		dist = range(from, sp);
95 		if (dist < olddist) {
96 			closest = sp;
97 			olddist = dist;
98 		}
99 	}
100 	return closest;
101 }
102 
103 int
angle(int dr,int dc)104 angle(int dr, int dc)
105 {
106 	int i;
107 
108 	if (dc >= 0 && dr > 0)
109 		i = 0;
110 	else if (dr <= 0 && dc > 0)
111 		i = 2;
112 	else if (dc <= 0 && dr < 0)
113 		i = 4;
114 	else
115 		i = 6;
116 	dr = abs(dr);
117 	dc = abs(dc);
118 	if ((i == 0 || i == 4) && dc * 2.4 > dr) {
119 		i++;
120 		if (dc > dr * 2.4)
121 			i++;
122 	} else if ((i == 2 || i == 6) && dr * 2.4 > dc) {
123 		i++;
124 		if (dr > dc * 2.4)
125 			i++;
126 	}
127 	return i % 8 + 1;
128 }
129 
130 /* checks for target bow or stern */
131 int
gunsbear(struct ship * from,struct ship * to)132 gunsbear(struct ship *from, struct ship *to)
133 {
134 	int Dr, Dc, i;
135 	int ang;
136 
137 	Dr = from->file->row - to->file->row;
138 	Dc = to->file->col - from->file->col;
139 	for (i = 2; i; i--) {
140 		if ((ang = angle(Dr, Dc) - from->file->dir + 1) < 1)
141 			ang += 8;
142 		if (ang >= 2 && ang <= 4)
143 			return 'r';
144 		if (ang >= 6 && ang <= 7)
145 			return 'l';
146 		Dr += dr[to->file->dir];
147 		Dc += dc[to->file->dir];
148 	}
149 	return 0;
150 }
151 
152 /* returns true if fromship is shooting at onship's starboard side */
153 int
portside(struct ship * from,struct ship * on,int quick)154 portside(struct ship *from, struct ship *on, int quick)
155 {
156 	int ang;
157 	int Dr, Dc;
158 
159 	Dr = from->file->row - on->file->row;
160 	Dc = on->file->col - from->file->col;
161 	if (quick == -1) {
162 		Dr += dr[on->file->dir];
163 		Dc += dc[on->file->dir];
164 	}
165 	ang = angle(Dr, Dc);
166 	if (quick != 0)
167 		return ang;
168 	ang = (ang + 4 - on->file->dir - 1) % 8 + 1;
169 	return ang < 5;
170 }
171 
172 int
colours(struct ship * sp)173 colours(struct ship *sp)
174 {
175 	char flag;
176 
177 	if (sp->file->struck) {
178 		flag = '!';
179 		return flag;
180 	}
181 	if (sp->file->explode)
182 		flag = '#';
183 	if (sp->file->sink)
184 		flag = '~';
185 	flag = *countryname[capship(sp)->nationality];
186 	return sp->file->FS ? flag : tolower((unsigned char)flag);
187 }
188 
189 void
logger(struct ship * s)190 logger(struct ship *s)
191 {
192 	FILE *fp;
193 	int persons;
194 	int n;
195 	struct logs log[NLOG];
196 	float net;
197 	struct logs *lp;
198 
199 	setegid(egid);
200 	if ((fp = fopen(_PATH_LOGFILE, "r+")) == NULL) {
201 		setegid(gid);
202 		return;
203 	}
204 	setegid(gid);
205 #ifdef LOCK_EX
206 	if (flock(fileno(fp), LOCK_EX) == -1)
207 		return;
208 #endif
209 	net = (float)s->file->points / s->specs->pts;
210 	persons = getw(fp);
211 	n = fread((char *)log, sizeof(struct logs), NLOG, fp);
212 	for (lp = &log[n]; lp < &log[NLOG]; lp++)
213 		lp->l_name[0] = lp->l_uid = lp->l_shipnum
214 			= lp->l_gamenum = lp->l_netpoints = 0;
215 	if (fseek(fp, 0L, SEEK_SET) == -1)
216 		err(1, "fseek");
217 	if (persons < 0)
218 		(void) putw(1, fp);
219 	else
220 		(void) putw(persons + 1, fp);
221 	for (lp = log; lp < &log[NLOG]; lp++)
222 		if (net > (float)lp->l_netpoints
223 		    / scene[lp->l_gamenum].ship[lp->l_shipnum].specs->pts) {
224 			(void) fwrite((char *)log,
225 				sizeof (struct logs), lp - log, fp);
226 			(void) strlcpy(log[NLOG-1].l_name, s->file->captain,
227 			    sizeof log[NLOG-1].l_name);
228 			log[NLOG-1].l_uid = getuid();
229 			log[NLOG-1].l_shipnum = s->file->index;
230 			log[NLOG-1].l_gamenum = game;
231 			log[NLOG-1].l_netpoints = s->file->points;
232 			(void) fwrite((char *)&log[NLOG-1],
233 				sizeof (struct logs), 1, fp);
234 			(void) fwrite((char *)lp,
235 				sizeof (struct logs), &log[NLOG-1] - lp, fp);
236 			break;
237 		}
238 #ifdef LOCK_EX
239 	(void) flock(fileno(fp), LOCK_UN);
240 #endif
241 	(void) fclose(fp);
242 }
243