1 #include <unistd.h>
2 #include <stdio.h>
3 #include <stdlib.h>
4 #include <sys/types.h>
5 #include <sys/wait.h>
6 #include <signal.h>
7 #include <math.h>
8
9 #define ROUNDS 20
10 #define SWAPS 40
11 int max_error = 5;
12 #include "common.h"
13
14
15
16 int pipefdc[2];
17 int pipefdp[2];
18 int subtest = 0;
19 int child_is_dead = 0;
20
21 void dead_child(int n);
22 void do_child(void);
23 void do_parent(void);
24 void do_calcs(void);
25 void err(int n);
26 void quit(void);
27
err(int n)28 void err(int n)
29 {
30 e(n);
31 }
32
do_calcs(void)33 void do_calcs(void)
34 {
35 float a, b, c, d, e;
36 float foo, bar;
37 int i;
38 subtest = 3;
39
40 a = 1.1;
41 b = 2.2;
42 c = 3.3;
43 d = 4.4;
44 e = 5.5;
45
46 foo = a * b; /* 2.42 */
47 bar = c * d; /* 14.52 */
48
49 i = 0;
50 while(i < ROUNDS) {
51 foo += c; /* 5.72 */
52 foo *= d; /* 25.168 */
53 foo /= e; /* 4.5760 */
54 bar -= a; /* 13.42 */
55 bar *= b; /* 29.524 */
56 bar /= e; /* 5.3680 */
57
58 /* Undo */
59 foo *= e;
60 foo /= d;
61 foo -= c;
62
63 bar *= e;
64 bar /= b;
65 bar += a;
66
67 i++;
68 }
69
70 if (fabs(foo - (a * b)) > 0.0001) err(1);
71 if (fabs(bar - (c * d)) > 0.0001) err(2);
72 }
73
dead_child(int n)74 void dead_child(int n)
75 {
76 int status;
77 subtest = 4;
78
79 (void) n; /* Avoid warning about unused parameter */
80
81 if (wait(&status) == -1) err(1);
82
83 if (!WIFEXITED(status)) {
84 err(2);
85 quit();
86 } else {
87 errct += WEXITSTATUS(status);
88 child_is_dead = 1;
89 }
90 }
91
do_child(void)92 void do_child(void)
93 {
94 char buf[2];
95 int s;
96
97 s = 0;
98 close(pipefdp[0]);
99 close(pipefdc[1]);
100
101 while(s < SWAPS) {
102 do_calcs();
103
104 /* Wake up parent */
105 write(pipefdp[1], buf, 1);
106
107 /* Wait for parent to wake me up */
108 read(pipefdc[0], buf, 1);
109
110 s++;
111 }
112 exit(0);
113 }
114
do_parent(void)115 void do_parent(void)
116 {
117 int s;
118 char buf[2];
119 struct sigaction sa;
120 subtest = 2;
121
122 sa.sa_handler = dead_child;
123 sa.sa_flags = 0;
124 if (sigaction(SIGCHLD, &sa, NULL) == -1) err(1);
125
126 s = 0;
127 close(pipefdp[1]);
128 close(pipefdc[0]);
129
130 while(s < SWAPS) {
131 /* Wait for child to wake me up */
132 read(pipefdp[0], buf, 1);
133
134 do_calcs();
135
136 /* Wake up child */
137 write(pipefdc[1], buf, 1);
138 s++;
139 }
140
141 while(child_is_dead == 0) { fflush(stdout); } /* Busy wait */
142
143 quit();
144 }
145
main(void)146 int main(void)
147 {
148 pid_t r;
149 subtest = 1;
150
151 start(52);
152
153 if (pipe(pipefdc) == -1) err(1);
154 if (pipe(pipefdp) == -1) err(2);
155
156 r = fork();
157 if(r < 0) {
158 err(3);
159 } else if(r == 0) {
160 /* Child */
161 do_child();
162 } else {
163 /* Parent */
164 do_parent();
165 }
166
167 return(0); /* Never reached */
168
169 }
170
171