1*73610d44SSepherosa Ziehau #include <sys/types.h>
2*73610d44SSepherosa Ziehau #include <sys/socket.h>
3*73610d44SSepherosa Ziehau #include <sys/wait.h>
4*73610d44SSepherosa Ziehau
5*73610d44SSepherosa Ziehau #include <arpa/inet.h>
6*73610d44SSepherosa Ziehau #include <netinet/in.h>
7*73610d44SSepherosa Ziehau
8*73610d44SSepherosa Ziehau #include <err.h>
9*73610d44SSepherosa Ziehau #include <errno.h>
10*73610d44SSepherosa Ziehau #include <signal.h>
11*73610d44SSepherosa Ziehau #include <stdio.h>
12*73610d44SSepherosa Ziehau #include <stdlib.h>
13*73610d44SSepherosa Ziehau #include <string.h>
14*73610d44SSepherosa Ziehau #include <unistd.h>
15*73610d44SSepherosa Ziehau
16*73610d44SSepherosa Ziehau static void
usage(const char * cmd)17*73610d44SSepherosa Ziehau usage(const char *cmd)
18*73610d44SSepherosa Ziehau {
19*73610d44SSepherosa Ziehau fprintf(stderr, "%s -p port\n", cmd);
20*73610d44SSepherosa Ziehau exit(1);
21*73610d44SSepherosa Ziehau }
22*73610d44SSepherosa Ziehau
23*73610d44SSepherosa Ziehau static void
connect_client(int port)24*73610d44SSepherosa Ziehau connect_client(int port)
25*73610d44SSepherosa Ziehau {
26*73610d44SSepherosa Ziehau struct sockaddr_in in;
27*73610d44SSepherosa Ziehau int s;
28*73610d44SSepherosa Ziehau
29*73610d44SSepherosa Ziehau s = socket(AF_INET, SOCK_STREAM, 0);
30*73610d44SSepherosa Ziehau if (s < 0)
31*73610d44SSepherosa Ziehau err(1, "client socket failed");
32*73610d44SSepherosa Ziehau
33*73610d44SSepherosa Ziehau memset(&in, 0, sizeof(in));
34*73610d44SSepherosa Ziehau in.sin_family = AF_INET;
35*73610d44SSepherosa Ziehau in.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
36*73610d44SSepherosa Ziehau in.sin_port = htons(port);
37*73610d44SSepherosa Ziehau if (connect(s, (const struct sockaddr *)&in, sizeof(in)) < 0)
38*73610d44SSepherosa Ziehau err(1, "connect failed");
39*73610d44SSepherosa Ziehau
40*73610d44SSepherosa Ziehau pause();
41*73610d44SSepherosa Ziehau exit(0);
42*73610d44SSepherosa Ziehau }
43*73610d44SSepherosa Ziehau
44*73610d44SSepherosa Ziehau int
main(int argc,char * argv[])45*73610d44SSepherosa Ziehau main(int argc, char *argv[])
46*73610d44SSepherosa Ziehau {
47*73610d44SSepherosa Ziehau struct sockaddr_in in;
48*73610d44SSepherosa Ziehau int serv_s, s;
49*73610d44SSepherosa Ziehau int opt, port, dummy, n, status, panic, ex;
50*73610d44SSepherosa Ziehau pid_t pid;
51*73610d44SSepherosa Ziehau
52*73610d44SSepherosa Ziehau ex = 1;
53*73610d44SSepherosa Ziehau panic = 0;
54*73610d44SSepherosa Ziehau
55*73610d44SSepherosa Ziehau port = 0;
56*73610d44SSepherosa Ziehau while ((opt = getopt(argc, argv, "p:")) != -1) {
57*73610d44SSepherosa Ziehau char *endptr;
58*73610d44SSepherosa Ziehau
59*73610d44SSepherosa Ziehau switch (opt) {
60*73610d44SSepherosa Ziehau case 'p':
61*73610d44SSepherosa Ziehau port = strtol(optarg, &endptr, 0);
62*73610d44SSepherosa Ziehau if (*endptr != '\0')
63*73610d44SSepherosa Ziehau errx(1, "invalid -p");
64*73610d44SSepherosa Ziehau break;
65*73610d44SSepherosa Ziehau
66*73610d44SSepherosa Ziehau default:
67*73610d44SSepherosa Ziehau usage(argv[0]);
68*73610d44SSepherosa Ziehau }
69*73610d44SSepherosa Ziehau }
70*73610d44SSepherosa Ziehau if (port <= 0)
71*73610d44SSepherosa Ziehau usage(argv[0]);
72*73610d44SSepherosa Ziehau
73*73610d44SSepherosa Ziehau serv_s = socket(AF_INET, SOCK_STREAM, 0);
74*73610d44SSepherosa Ziehau if (serv_s < 0)
75*73610d44SSepherosa Ziehau err(1, "socket failed");
76*73610d44SSepherosa Ziehau
77*73610d44SSepherosa Ziehau memset(&in, 0, sizeof(in));
78*73610d44SSepherosa Ziehau in.sin_family = AF_INET;
79*73610d44SSepherosa Ziehau in.sin_port = htons(port);
80*73610d44SSepherosa Ziehau if (bind(serv_s, (const struct sockaddr *)&in, sizeof(in)) < 0)
81*73610d44SSepherosa Ziehau err(1, "bind failed");
82*73610d44SSepherosa Ziehau
83*73610d44SSepherosa Ziehau if (listen(serv_s, 0) < 0)
84*73610d44SSepherosa Ziehau err(1, "listen failed");
85*73610d44SSepherosa Ziehau
86*73610d44SSepherosa Ziehau pid = fork();
87*73610d44SSepherosa Ziehau if (pid < 0) {
88*73610d44SSepherosa Ziehau err(1, "fork failed");
89*73610d44SSepherosa Ziehau } else if (pid == 0) {
90*73610d44SSepherosa Ziehau connect_client(port);
91*73610d44SSepherosa Ziehau abort();
92*73610d44SSepherosa Ziehau }
93*73610d44SSepherosa Ziehau
94*73610d44SSepherosa Ziehau s = accept4(serv_s, NULL, NULL, SOCK_NONBLOCK);
95*73610d44SSepherosa Ziehau if (s < 0) {
96*73610d44SSepherosa Ziehau warn("accept4 failed");
97*73610d44SSepherosa Ziehau goto done;
98*73610d44SSepherosa Ziehau }
99*73610d44SSepherosa Ziehau panic = 1;
100*73610d44SSepherosa Ziehau
101*73610d44SSepherosa Ziehau n = read(s, &dummy, sizeof(dummy));
102*73610d44SSepherosa Ziehau if (n < 0) {
103*73610d44SSepherosa Ziehau int error = errno;
104*73610d44SSepherosa Ziehau
105*73610d44SSepherosa Ziehau if (error != EAGAIN) {
106*73610d44SSepherosa Ziehau warnx("invaid errno %d", error);
107*73610d44SSepherosa Ziehau goto done;
108*73610d44SSepherosa Ziehau }
109*73610d44SSepherosa Ziehau } else {
110*73610d44SSepherosa Ziehau warnx("read works");
111*73610d44SSepherosa Ziehau goto done;
112*73610d44SSepherosa Ziehau }
113*73610d44SSepherosa Ziehau
114*73610d44SSepherosa Ziehau ex = 0;
115*73610d44SSepherosa Ziehau panic = 0;
116*73610d44SSepherosa Ziehau fprintf(stderr, "passed\n");
117*73610d44SSepherosa Ziehau done:
118*73610d44SSepherosa Ziehau kill(pid, SIGKILL);
119*73610d44SSepherosa Ziehau waitpid(pid, &status, 0);
120*73610d44SSepherosa Ziehau if (panic)
121*73610d44SSepherosa Ziehau abort();
122*73610d44SSepherosa Ziehau exit(ex);
123*73610d44SSepherosa Ziehau }
124