您的位置：首页 > 其它

epoll测试实例

2015-08-26 17:19 344 查看
C++ Code
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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <netdb.h>

#include <unistd.h>

#include <fcntl.h>

#include <sys/epoll.h>

#include <errno.h>

#define MAXEVENTS 64

static int

make_socket_non_blocking (int sfd)

{

int flags, s;

flags = fcntl (sfd, F_GETFL, 0);

if (flags == -1)

{

perror ("fcntl");

return -1;

}

flags |= O_NONBLOCK;

s = fcntl (sfd, F_SETFL, flags);

if (s == -1)

{

perror ("fcntl");

return -1;

}

return 0;

}

static int

create_and_bind (char *port)

{

struct addrinfo hints;

struct addrinfo *result, *rp;

int s, sfd;

memset (&hints, 0, sizeof (struct addrinfo));

hints.ai_family = AF_UNSPEC; /* Return IPv4 and IPv6 choices */

hints.ai_socktype = SOCK_STREAM; /* We want a TCP socket */

hints.ai_flags = AI_PASSIVE; /* All interfaces */

s = getaddrinfo (NULL, port, &hints, &result);

if (s != 0)

{

fprintf (stderr, "getaddrinfo: %s\n", gai_strerror (s));

return -1;

}

for (rp = result; rp != NULL; rp = rp->ai_next)

{

sfd = socket (rp->ai_family, rp->ai_socktype, rp->ai_protocol);

if (sfd == -1)

{

continue;

}

s = bind (sfd, rp->ai_addr, rp->ai_addrlen);

if (s == 0)

{

/* We managed to bind successfully! */

break;

}

close (sfd);

}

if (rp == NULL)

{

fprintf (stderr, "Could not bind\n");

return -1;

}

freeaddrinfo (result);

return sfd;

}

int

main (int argc, char *argv[])

{

int sfd, s;

int efd;

struct epoll_event event;

struct epoll_event *events;

if (argc != 2)

{

fprintf (stderr, "Usage: %s [port]\n", argv[0]);

exit (EXIT_FAILURE);

}

sfd = create_and_bind (argv[1]);

if (sfd == -1)

{

abort ();

}

s = make_socket_non_blocking (sfd);

if (s == -1)

{

abort ();

}

s = listen (sfd, SOMAXCONN);

if (s == -1)

{

perror ("listen");

abort ();

}

efd = epoll_create1 (0);

if (efd == -1)

{

perror ("epoll_create");

abort ();

}

event.data.fd = sfd;

event.events = EPOLLIN | EPOLLET;

s = epoll_ctl (efd, EPOLL_CTL_ADD, sfd, &event);

if (s == -1)

{

perror ("epoll_ctl");

abort ();

}

/* Buffer where events are returned */

events = calloc (MAXEVENTS, sizeof event);

/* The event loop */

while (1)

{

int n, i;

n = epoll_wait (efd, events, MAXEVENTS, -1);

for (i = 0; i < n; i++)

{

if ((events[i].events & EPOLLERR) ||

(events[i].events & EPOLLHUP) ||

(!(events[i].events & EPOLLIN)))

{

/* An error has occured on this fd, or the socket is not

ready for reading (why were we notified then?) */

fprintf (stderr, "epoll error\n");

close (events[i].data.fd);

continue;

}

else if (sfd == events[i].data.fd)

{

/* We have a notification on the listening socket, which

means one or more incoming connections. */

while (1)

{

struct sockaddr in_addr;

socklen_t in_len;

int infd;

char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];

in_len = sizeof in_addr;

infd = accept (sfd, &in_addr, &in_len);

if (infd == -1)

{

if ((errno == EAGAIN) ||

(errno == EWOULDBLOCK))

{

/* We have processed all incoming

connections. */

break;

}

else

{

perror ("accept");

break;

}

}

s = getnameinfo (&in_addr, in_len,

hbuf, sizeof hbuf,

sbuf, sizeof sbuf,

NI_NUMERICHOST | NI_NUMERICSERV);

if (s == 0)

{

printf("Accepted connection on descriptor %d "

"(host=%s, port=%s)\n", infd, hbuf, sbuf);

}

/* Make the incoming socket non-blocking and add it to the

list of fds to monitor. */

s = make_socket_non_blocking (infd);

if (s == -1)

{

abort ();

}

event.data.fd = infd;

event.events = EPOLLIN | EPOLLET;

s = epoll_ctl (efd, EPOLL_CTL_ADD, infd, &event);

if (s == -1)

{

perror ("epoll_ctl");

abort ();

}

}

continue;

}

else

{

/* We have data on the fd waiting to be read. Read and

display it. We must read whatever data is available

completely, as we are running in edge-triggered mode

and won't get a notification again for the same

data. */

int done = 0;

while (1)

{

ssize_t count;

char buf[512];

count = read (events[i].data.fd, buf, sizeof buf);

if (count == -1)

{

/* If errno == EAGAIN, that means we have read all

data. So go back to the main loop. */

if (errno != EAGAIN)

{

perror ("read");

done = 1;

}

break;

}

else if (count == 0)

{

/* End of file. The remote has closed the

connection. */

done = 1;

break;

}

/* Write the buffer to standard output */

s = write (1, buf, count);

if (s == -1)

{

perror ("write");

abort ();

}

}

if (done)

{

printf ("Closed connection on descriptor %d\n",

events[i].data.fd);

/* Closing the descriptor will make epoll remove it

from the set of descriptors which are monitored. */

close (events[i].data.fd);

}

}

}

}

free (events);

close (sfd);

return EXIT_SUCCESS;

}

具体函数介绍请参考：https://banu.com/blog/2/how-to-use-epoll-a-complete-example-in-c/

运行结果：

服务器端：



客户端：

内容来自用户分享和网络整理，不保证内容的准确性，如有侵权内容，可联系管理员处理 点击这里给我发消息
标签： 
相关文章推荐
新的分享
章节导航