1 /*        $NetBSD: misc.c,v 1.18 2009/03/14 19:35:13 dholland Exp $   */
2 
3 /*
4  * Copyright (c) 1983, 1993
5  *        The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)misc.c      8.2 (Berkeley) 4/28/95";
36 #else
37 __RCSID("$NetBSD: misc.c,v 1.18 2009/03/14 19:35:13 dholland Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include <ctype.h>
42 #include <stdio.h>
43 #include <unistd.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include "extern.h"
47 #include "pathnames.h"
48 
49 #define distance(x,y) \
50           (abs(x) >= abs(y) ? abs(x) + abs(y)/2 : abs(y) + abs(x)/2)
51 
52 static int angle(int, int);
53 
54 /* XXX */
55 int
range(struct ship * from,struct ship * to)56 range(struct ship *from, struct ship *to)
57 {
58           int bow1r, bow1c, bow2r, bow2c;
59           int stern1r, stern1c, stern2c, stern2r;
60           int bb, bs, sb, ss, result;
61 
62           if (!to->file->dir)
63                     return -1;
64           stern1r = bow1r = from->file->row;
65           stern1c = bow1c = from->file->col;
66           stern2r = bow2r = to->file->row;
67           stern2c = bow2c = to->file->col;
68           result = bb = distance(bow2r - bow1r, bow2c - bow1c);
69           if (bb < 5) {
70                     stern2r += dr[to->file->dir];
71                     stern2c += dc[to->file->dir];
72                     stern1r += dr[from->file->dir];
73                     stern1c += dc[from->file->dir];
74                     bs = distance((bow2r - stern1r), (bow2c - stern1c));
75                     sb = distance((bow1r - stern2r), (bow1c - stern2c));
76                     ss = distance((stern2r - stern1r) ,(stern2c - stern1c));
77                     result = min(bb, min(bs, min(sb, ss)));
78           }
79           return result;
80 }
81 
82 struct ship *
closestenemy(struct ship * from,int side,int anyship)83 closestenemy(struct ship *from, int side, int anyship)
84 {
85           struct ship *sp;
86           char a;
87           int olddist = 30000, dist;
88           struct ship *closest = 0;
89 
90           a = capship(from)->nationality;
91           foreachship(sp) {
92                     if (sp == from)
93                               continue;
94                     if (sp->file->dir == 0)
95                               continue;
96                     if (a == capship(sp)->nationality && !anyship)
97                               continue;
98                     if (side && gunsbear(from, sp) != side)
99                               continue;
100                     dist = range(from, sp);
101                     if (dist < olddist) {
102                               closest = sp;
103                               olddist = dist;
104                     }
105           }
106           return closest;
107 }
108 
109 static int
angle(int Dr,int Dc)110 angle(int Dr, int Dc)
111 {
112           int i;
113 
114           if (Dc >= 0 && Dr > 0)
115                     i = 0;
116           else if (Dr <= 0 && Dc > 0)
117                     i = 2;
118           else if (Dc <= 0 && Dr < 0)
119                     i = 4;
120           else
121                     i = 6;
122           Dr = abs(Dr);
123           Dc = abs(Dc);
124           if ((i == 0 || i == 4) && Dc * 2.4 > Dr) {
125                     i++;
126                     if (Dc > Dr * 2.4)
127                               i++;
128           } else if ((i == 2 || i == 6) && Dr * 2.4 > Dc) {
129                     i++;
130                     if (Dr > Dc * 2.4)
131                               i++;
132           }
133           return i % 8 + 1;
134 }
135 
136 /* checks for target bow or stern */
137 int
gunsbear(struct ship * from,struct ship * to)138 gunsbear(struct ship *from, struct ship *to)
139 {
140           int Dr, Dc, i;
141           int ang;
142 
143           Dr = from->file->row - to->file->row;
144           Dc = to->file->col - from->file->col;
145           for (i = 2; i; i--) {
146                     if ((ang = angle(Dr, Dc) - from->file->dir + 1) < 1)
147                               ang += 8;
148                     if (ang >= 2 && ang <= 4)
149                               return 'r';
150                     if (ang >= 6 && ang <= 7)
151                               return 'l';
152                     Dr += dr[to->file->dir];
153                     Dc += dc[to->file->dir];
154           }
155           return 0;
156 }
157 
158 /* returns true if fromship is shooting at onship's starboard side */
159 int
portside(struct ship * from,struct ship * on,int quick)160 portside(struct ship *from, struct ship *on, int quick)
161 {
162           int ang;
163           int Dr, Dc;
164 
165           Dr = from->file->row - on->file->row;
166           Dc = on->file->col - from->file->col;
167           if (quick == -1) {
168                     Dr += dr[on->file->dir];
169                     Dc += dc[on->file->dir];
170           }
171           ang = angle(Dr, Dc);
172           if (quick != 0)
173                     return ang;
174           ang = (ang + 4 - on->file->dir - 1) % 8 + 1;
175           return ang < 5;
176 }
177 
178 int
colours(struct ship * sp)179 colours(struct ship *sp)
180 {
181           char flag = '\0';
182 
183           if (sp->file->struck)
184                     flag = '!';
185           if (sp->file->explode)
186                     flag = '#';
187           if (sp->file->sink)
188                     flag = '~';
189           if (sp->file->struck)
190                     return flag;
191           flag = *countryname[capship(sp)->nationality];
192           return sp->file->FS ? flag : tolower((unsigned char)flag);
193 }
194 
195 void
logger(struct ship * s)196 logger(struct ship *s)
197 {
198           FILE *fp;
199           int persons;
200           int n;
201           struct logs log[NLOG];
202           float net;
203           struct logs *lp;
204 
205           setegid(egid);
206           if ((fp = fopen(_PATH_LOGFILE, "r+")) == NULL) {
207                     setegid(gid);
208                     return;
209           }
210           setegid(gid);
211 #ifdef LOCK_EX
212           if (flock(fileno(fp), LOCK_EX) < 0)
213                     return;
214 #endif
215           net = (float)s->file->points / s->specs->pts;
216           persons = getw(fp);
217           n = fread(log, sizeof(struct logs), NLOG, fp);
218           for (lp = &log[n]; lp < &log[NLOG]; lp++)
219                     lp->l_name[0] = lp->l_uid = lp->l_shipnum
220                               = lp->l_gamenum = lp->l_netpoints = 0;
221           rewind(fp);
222           if (persons < 0)
223                     putw(1, fp);
224           else
225                     putw(persons + 1, fp);
226           for (lp = log; lp < &log[NLOG]; lp++)
227                     if (net > (float)lp->l_netpoints
228                         / scene[lp->l_gamenum].ship[lp->l_shipnum].specs->pts) {
229                               fwrite(log, sizeof (struct logs), lp - log, fp);
230                               strcpy(log[NLOG-1].l_name, s->file->captain);
231                               log[NLOG-1].l_uid = getuid();
232                               log[NLOG-1].l_shipnum = s->file->index;
233                               log[NLOG-1].l_gamenum = game;
234                               log[NLOG-1].l_netpoints = s->file->points;
235                               fwrite(&log[NLOG-1], sizeof (struct logs), 1, fp);
236                               fwrite(lp, sizeof (struct logs), &log[NLOG-1] - lp, fp);
237                               break;
238                     }
239 #ifdef LOCK_EX
240           flock(fileno(fp), LOCK_UN);
241 #endif
242           fclose(fp);
243 }
244