-
Notifications
You must be signed in to change notification settings - Fork 0
/
planksockets.cpp
133 lines (110 loc) · 3.61 KB
/
planksockets.cpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
// Many thanks and all credit to Dr. Plank for this one
#pragma once
#include <cstring>
#include <fcntl.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <cstdio>
#include <stdlib.h>
namespace NeuroUtils {
/*
SocketAccept():
Serves a socket using the given port and accepts a connection on it.
Returns a file descriptor for the connection.
Example usage:
int port = 5456;
int fd = SocketAccept(port);
if(fd <= 0) { perror("SocketAccept"); exit(1);}
FILE* fin = fdopen(fd, "r");
FILE* fout = fdopen(fd, "w");
// Send a message
fprintf(fout, "Hello! I'm using port %d\n", port);
fflush(fout);
// Receive a message
char buf[1000];
if (fgets(buf, 1000, fin) != NULL)
printf("I got the message: %s\n", buf);
else
printf("Connection closed\n");
*/
int SocketAccept(int port)
{
int sock;
struct sockaddr_in serv_addr, cli_addr;
sock = socket(AF_INET, SOCK_STREAM, 0);
if(sock == -1) {
perror("SocketAccept: ERROR opening socket");
exit(1);
}
memset(&serv_addr, 0, sizeof(serv_addr));
memset(&cli_addr, 0, sizeof(cli_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(port);
// This should help us dodge the "address in use" error as much as possible
int yes = 1;
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) == -1) {
perror("setsockopt");
exit(1);
}
if(::bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr))) {
perror("SocketAccept: bind()");
exit(1);
}
if(listen(sock, 500)) {
perror("SocketAccept: listen()");
exit(1);
}
return accept(sock, (struct sockaddr *) NULL, NULL);
}
/*
SocketRequest():
Connects to the given host using the given port. Returns a file descriptor
for the connection. This retries connecting to the given host and port
until the connection is accepted, sleeping 1 second between tries.
Example usage:
int port = 5456;
int fd = SocketRequest("localhost", port);
FILE* fin = fdopen(fd, "r");
FILE* fout = fdopen(fd, "w");
// Send a message
fprintf(fout, "Hello! I'm using port %d\n", port);
fflush(fout);
// Receive a message
char buf[1000];
if (fgets(buf, 1000, fin) != NULL)
printf("I got the message: %s\n", buf);
else
printf("Connection closed\n");
*/
int SocketRequest(const char* host, int port)
{
int fd;
struct hostent *he;
struct sockaddr_in serv_addr;
bool ok;
fd = socket(AF_INET, SOCK_STREAM, 0);
if(fd == -1){
perror("SocketRequest: ERROR opening socket");
exit(1);
}
he = gethostbyname(host);
if(he == NULL){
fprintf(stderr, "SocketRequest: ERROR, no such host '%s'\n", host);
exit(0);
}
ok = false;
while(!ok) {
bzero((char *) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_port = htons(port);
serv_addr.sin_addr = *(struct in_addr *)(he->h_addr_list[0]);
ok = (connect(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) != -1);
if(!ok) {sleep(1); fprintf(stderr, "Waiting to connect to %s: %d\n", host, port);}
}
return fd;
}
}