Bug Summary

File:src/games/sail/misc.c
Warning:line 184, column 3
Value stored to 'flag' is never read

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name misc.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -pic-is-pie -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -target-feature +retpoline-indirect-calls -target-feature +retpoline-indirect-branches -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/games/sail/obj -resource-dir /usr/local/lib/clang/13.0.0 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -fdebug-compilation-dir=/usr/src/games/sail/obj -ferror-limit 19 -fwrapv -D_RET_PROTECTOR -ret-protector -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c /usr/src/games/sail/misc.c
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) (abs(x) >= abs(y) ? abs(x) + abs(y)/2 : abs(y) + abs(x)/2)
47
48/* XXX */
49int
50range(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)(abs(bow2r - bow1r) >= abs(bow2c - bow1c) ? abs(bow2r - bow1r
) + abs(bow2c - bow1c)/2 : abs(bow2c - bow1c) + abs(bow2r - bow1r
)/2)
;
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))(abs((bow2r - stern1r)) >= abs((bow2c - stern1c)) ? abs((bow2r
- stern1r)) + abs((bow2c - stern1c))/2 : abs((bow2c - stern1c
)) + abs((bow2r - stern1r))/2)
;
69 sb = distance((bow1r - stern2r), (bow1c - stern2c))(abs((bow1r - stern2r)) >= abs((bow1c - stern2c)) ? abs((bow1r
- stern2r)) + abs((bow1c - stern2c))/2 : abs((bow1c - stern2c
)) + abs((bow1r - stern2r))/2)
;
70 ss = distance((stern2r - stern1r) ,(stern2c - stern1c))(abs((stern2r - stern1r)) >= abs((stern2c - stern1c)) ? abs
((stern2r - stern1r)) + abs((stern2c - stern1c))/2 : abs((stern2c
- stern1c)) + abs((stern2r - stern1r))/2)
;
71 result = min(bb, min(bs, min(sb, ss)))((bb) < (((bs) < (((sb) < (ss) ? (sb) : (ss))) ? (bs
) : (((sb) < (ss) ? (sb) : (ss))))) ? (bb) : (((bs) < (
((sb) < (ss) ? (sb) : (ss))) ? (bs) : (((sb) < (ss) ? (
sb) : (ss))))))
;
72 }
73 return result;
74}
75
76struct ship *
77closestenemy(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)((from)->file->captured?(from)->file->captured:(from
))
->nationality;
85 foreachship(sp)for ((sp) = cc->ship; (sp) < ls; (sp)++) {
86 if (sp == from)
87 continue;
88 if (sp->file->dir == 0)
89 continue;
90 if (a == capship(sp)((sp)->file->captured?(sp)->file->captured:(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
103int
104angle(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 */
131int
132gunsbear(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 */
153int
154portside(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
172int
173colours(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 = '~';
Value stored to 'flag' is never read
185 flag = *countryname[capship(sp)((sp)->file->captured?(sp)->file->captured:(sp))->nationality];
186 return sp->file->FS ? flag : tolower((unsigned char)flag);
187}
188
189void
190logger(struct ship *s)
191{
192 FILE *fp;
193 int persons;
194 int n;
195 struct logs log[NLOG10];
196 float net;
197 struct logs *lp;
198
199 setegid(egid);
200 if ((fp = fopen(_PATH_LOGFILE"/var/games/saillog", "r+")) == NULL((void *)0)) {
201 setegid(gid);
202 return;
203 }
204 setegid(gid);
205#ifdef LOCK_EX
206 if (flock(fileno(fp)(!__isthreaded ? ((fp)->_file) : (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), NLOG10, fp);
212 for (lp = &log[n]; lp < &log[NLOG10]; 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_SET0) == -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[NLOG10]; 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[NLOG10-1].l_name, s->file->captain,
227 sizeof log[NLOG10-1].l_name);
228 log[NLOG10-1].l_uid = getuid();
229 log[NLOG10-1].l_shipnum = s->file->index;
230 log[NLOG10-1].l_gamenum = game;
231 log[NLOG10-1].l_netpoints = s->file->points;
232 (void) fwrite((char *)&log[NLOG10-1],
233 sizeof (struct logs), 1, fp);
234 (void) fwrite((char *)lp,
235 sizeof (struct logs), &log[NLOG10-1] - lp, fp);
236 break;
237 }
238#ifdef LOCK_EX
239 (void) flock(fileno(fp)(!__isthreaded ? ((fp)->_file) : (fileno)(fp)), LOCK_UN);
240#endif
241 (void) fclose(fp);
242}