1 #include <iostream>
2 #include <sstream>
3 #include <map>
4
5 #include <stdio.h>
6 #include <errno.h>
7 #include <string.h>
8
9 #include <sys/socket.h>
10 #include <netinet/in.h>
11 #include <arpa/inet.h>
12
13 #include <unistd.h>
14 #include <fcntl.h>
15 #include <poll.h>
16
17 #define LOCAL_AF AF_INET // 本地地址类型
18 #define LOCAL_IP_ADDR "172.20.0.115"
19 #define LOCAL_PORT 8090
20
21 #define BACKLOG 10 // 监听等待队列个数
22
23 #define MAX_FD 1024 // 最大打开文件描述符数目
24 #define MAX_USER 3 // 最大用户数
25
26 #define FAILED_TEST_CNT 10 // socket调用失败, 连续测试次数
27
28 // 统计连接socket和对应的socket连续调用失败次数, 失败 FAILED_TEST_CNT 次，关闭移除socket
29 typedef std::map<int, int> Clients;
30
31 using namespace std;
32
33 static void showErr()
34 {
35 printf("errno: %d, err_msg: %s\n", errno, strerror(errno));
36 }
37
38 // 设置socket为非阻塞
39 static bool setSocketNonBlock(int socketFd)
40 {
41 int flags = fcntl(socketFd, F_GETFL);
42 if (-1 == flags)
43 {
44 cout << "fcntl F_GETFL error" << endl;
45 return false;
46 }
47
48 int ret = fcntl(socketFd, F_SETFL, O_NONBLOCK | flags);
49 if (-1 == ret)
50 {
51 cout << "fcntl F_SETFL error" << endl;
52 return false;
53 }
54 return true;
55 }
56
57 // 设置socket关闭时不等待缓存区数据发送完毕(等待可能导致缓冲区数据无法发送导致一直占用端口: 连接一直处于FIN_WAIT1状态)
58 static int disableLinger(int socketFd)
59 {
60 struct linger lingerVal;
61 lingerVal.l_onoff = 1;
62 lingerVal.l_linger = 0;
63 int ret = setsockopt(socketFd, SOL_SOCKET, SO_LINGER, &lingerVal, sizeof(lingerVal));
64 if (0 != ret)
65 {
66 cout << "setsockopt linger error" << endl;
67 return false;
68 }
69 return true;
70 }
71
72 int main(int argc, char **argv)
73 {
74 int ret(0);
75
76 // 生成监听socket
77 int listenSocket(-1);
78 listenSocket = socket(LOCAL_AF, SOCK_STREAM, IPPROTO_TCP);
79 if (-1 == listenSocket)
80 {
81 cout << "socket error" << endl;
82 return 1;
83 }
84
85 if (!setSocketNonBlock(listenSocket))
86 {
87 return 1;
88 }
89
90 if (!disableLinger(listenSocket))
91 {
92 return 1;
93 }
94
95 // 绑定监听socket到指定网卡和端口
96 in_addr localAddr;
97 inet_pton(LOCAL_AF, LOCAL_IP_ADDR, &localAddr);
98 sockaddr_in localSockAddr;
99 localSockAddr.sin_family = LOCAL_AF;
100 localSockAddr.sin_addr = localAddr;
101 // localSockAddr.sin_addr.s_addr = htonl(INADDR_ANY); // 绑定到所有网卡的指定端口(多网卡自适应)
102 localSockAddr.sin_port = htons(LOCAL_PORT);
103 ret = bind(listenSocket, (sockaddr *)&localSockAddr, sizeof(localSockAddr));
104 if (0 != ret)
105 {
106 cout << "bind error" << endl;
107 return 1;
108 }
109
110 ret = listen(listenSocket, BACKLOG);
111 if (0 != ret)
112 {
113 cout << "listen error" << endl;
114 return 1;
115 }
116
117 // 创建pollfd结构体数组, 使用poll函数管理监听socket和所有的连接socket
118 pollfd pollFds[MAX_FD];
119 memset(pollFds, 0, sizeof(pollFds)); // memset初始化内存只适用于POD类型
120 int usedFdIdx = -1; // 已用到的pollfd数组索引
121
122 // 将监听socket纳入pollfd数组第一个元素
123 ++usedFdIdx;
124 pollFds[usedFdIdx].fd = listenSocket;
125 pollFds[usedFdIdx].events = POLLIN; // 客户端请求到达事件(connect等)
126
127 Clients clients;
128
129 bool done(false);
130 while (!done)
131 {
132 ret = poll(pollFds, usedFdIdx + 1, 1000); // 等待1秒
133 switch(ret)
134 {
135 case -1:
136 showErr();
137 return 1;
138 case 0:
139 cout << "timeout" << endl;
140 break;
141 default:
142 // 遍历客户端连接socket
143 for (int idx = 1; idx <= usedFdIdx; ++idx)
144 {
145 Clients::iterator iter = clients.find(pollFds[idx].fd);
146
147 // 客户端可写
148 if (pollFds[idx].revents & POLLOUT)
149 {
150 string msg = "i‘m client\r\n";
151 ret = send(pollFds[idx].fd, msg.c_str(), msg.length(), 0);
152 // send failed
153 if (-1 == ret && EAGAIN != errno) // EAGAIN代表缓冲区满了, 不是错误需要排除
154 {
155 iter->second++;
156
157 // 连续
158 if (iter->second >= 10)
159 {
160 ret = close(pollFds[idx].fd);
161 if (0 == ret)
162 {
163 cout << "close socket :" << pollFds[idx].fd << " success" <<endl;
164 }
165 else
166 {
167 cout << "close socket :" << pollFds[idx].fd << " failed" <<endl;
168 }
169
170 clients.erase(iter);
171 for (int i = idx; i < usedFdIdx; ++i)
172 {
173 pollFds[i] = pollFds[i + 1];
174 }
175 --usedFdIdx;
176 }
177 }
178 else
179 {
180 iter->second = 0;
181 }
182
183 cout << "send ret: " << ret << endl;
184 }
185 else if (pollFds[idx].revents & POLLERR)
186 {
187 cout << pollFds[idx].fd << " error" << endl;
188
189 iter->second++;
190
191 // remove socket
192 if (iter->second >= 10)
193 {
194 ret = close(pollFds[idx].fd);
195 if (0 == ret)
196 {
197 cout << "close socket :" << pollFds[idx].fd << " success" <<endl;
198 }
199 else
200 {
201 cout << "close socket :" << pollFds[idx].fd << " failed" <<endl;
202 }
203
204 clients.erase(iter);
205 for (int i = idx; i < usedFdIdx; ++i)
206 {
207 pollFds[i] = pollFds[i + 1];
208 }
209 --usedFdIdx;
210 }
211 }
212
213 if (idx == usedFdIdx)
214 {
215 sleep(1);
216 }
217 }
218
219 // 客户端connect请求到达
220 if (pollFds[0].revents & POLLIN)
221 {
222 if (usedFdIdx < MAX_USER)
223 {
224 int connectSocket(-1);
225 connectSocket = accept(listenSocket, NULL, NULL);
226 if (-1 == connectSocket)
227 {
228 cout << "accept error" << endl;
229 break;
230 }
231 cout << "accept success" << endl;
232
233 if (!setSocketNonBlock(connectSocket))
234 {
235 break;
236 }
237
238 if (!disableLinger(connectSocket))
239 {
240 break;
241 }
242
243 // 连接socket使用poll管理
244 ++usedFdIdx;
245 pollFds[usedFdIdx].fd = connectSocket;
246 pollFds[usedFdIdx].events = POLLOUT;
247
248 //
249 clients.insert(make_pair<int, int>(connectSocket, 0));
250 }
251 else // fd too many
252 {
253
254 }
255 }
256 }
257 }
258
259
260 return 0;
261 }
时间： 2024-10-16 22:09:38