TCP服务器/客户端代码示例

TCP服务器代码：

  1 #include <errno.h>
  2 #include <string.h>
  3 #include <stdlib.h>
  4 #include <sys/types.h>
  5 #include <sys/socket.h>
  6 #include <netinet/in.h>
  7 #include <arpa/inet.h>
  8 #include <iostream>
  9
 10 using namespace std;
 11
 12 int main(int argc, char *argv[])
 13 {
 14     if (argc != 3)
 15     {
 16         cout << "usage: " << argv[0] << " ip port" << endl;
 17         return -1;
 18     }
 19
 20     char *szIp = argv[1];
 21     in_addr_t iIp = inet_addr(szIp);
 22     if (iIp == INADDR_NONE)
 23     {
 24         cerr << "fail to parse ip: " << szIp << endl;
 25         return -1;
 26     }
 27     char *pEnd = NULL;
 28     uint16_t usPort = strtoul(argv[2], &pEnd, 10);
 29     if (*pEnd != ‘\0‘)
 30     {
 31         cerr << "fail to parse port: " << argv[2] << endl;
 32         return -1;
 33     }
 34
 35     int iSockFd = socket(AF_INET, SOCK_STREAM, 0);
 36     if (iSockFd < 0)
 37     {
 38         cerr << "fail to create socket, err: " << strerror(errno) << endl;
 39         return -1;
 40     }
 41     cout << "create socket fd " << iSockFd << endl;
 42
 43     sockaddr_in oAddr;
 44     memset(&oAddr, 0, sizeof(oAddr));
 45     oAddr.sin_family = AF_INET;
 46     oAddr.sin_addr.s_addr = iIp;
 47     oAddr.sin_port = htons(usPort);
 48     if (bind(iSockFd, (sockaddr *)&oAddr, sizeof(oAddr)) < 0)
 49     {
 50         cerr << "fail to bind addr " << szIp << ":" << usPort << ", err: " << strerror(errno) << endl;
 51         return -1;
 52     }
 53     cout << "bind addr " << szIp << ":" << usPort << endl;
 54
 55     if (listen(iSockFd, 100) < 0)
 56     {
 57         cerr << "fail to listen on " << szIp << ":" << usPort << ", err: " << strerror(errno) << endl;
 58     }
 59     cout << "listen on socket fd " << iSockFd << endl;
 60
 61     uint8_t acRecvBuf[1024 * 1024];
 62     while (true)
 63     {
 64         sockaddr_in oClientAddr;
 65         socklen_t iAddrLen = sizeof(oClientAddr);
 66         int iAcceptFd = accept(iSockFd, (sockaddr *)&oClientAddr, &iAddrLen);
 67         if (iAcceptFd < 0)
 68         {
 69             cerr << "fail to accpet, err: " << strerror(errno) << endl;
 70             continue;
 71         }
 72         cout << "recv connection from " << inet_ntoa(oClientAddr.sin_addr) << ":" << ntohs(oClientAddr.sin_port) << endl;
 73
 74         while (true)
 75         {
 76             ssize_t iRecvLen = recv(iAcceptFd, acRecvBuf, sizeof(acRecvBuf), 0);
 77             if (iRecvLen < 0)
 78             {
 79                 cerr << "fail to recv, close connection, err: " << strerror(errno) << endl;
 80                 close(iAcceptFd);
 81                 break;
 82             }
 83             if (iRecvLen == 0)
 84             {
 85                 cout << "connection closed by client" << endl;
 86                 close(iAcceptFd);
 87                 break;
 88             }
 89             cout << "recv data len: " << iRecvLen << endl;
 90
 91             ssize_t iSendLen = send(iAcceptFd, acRecvBuf, iRecvLen, 0);
 92             if (iSendLen < 0)
 93             {
 94                 cerr << "fail to send, err: " << strerror(errno) << endl;
 95                 close(iAcceptFd);
 96                 break;
 97             }
 98             cout << "echo to client, len: " << iSendLen << endl;
 99         }
100
101     }
102 }

TCP客户端代码:

 1 #include <errno.h>
 2 #include <string.h>
 3 #include <sys/types.h>
 4 #include <sys/socket.h>
 5 #include <netinet/in.h>
 6 #include <arpa/inet.h>
 7 #include <stdlib.h>
 8 #include <iostream>
 9
10 using namespace std;
11
12 int main(int argc, char *argv[])
13 {
14     if (argc != 4)
15     {
16         cout << "usage: " << argv[0] << " ip port message" << endl;
17         return -1;
18     }
19
20     char *szIp = argv[1];
21     in_addr_t iIp = inet_addr(szIp);
22     if (iIp == INADDR_NONE)
23     {
24         cerr << "fail to parse ip: " << szIp << endl;
25         return -1;
26     }
27     char *pEnd = NULL;
28     uint16_t usPort = strtoul(argv[2], &pEnd, 10);
29     if (*pEnd != ‘\0‘)
30     {
31         cerr << "fail to parse port: " << argv[2] << endl;
32         return -1;
33     }
34     char *szMsg = argv[3];
35     size_t uiMsgLen = strlen(szMsg);
36
37     int iSockFd = socket(AF_INET, SOCK_STREAM, 0);
38     if (iSockFd < 0)
39     {
40         cerr << "fail to create socket, err: " << strerror(errno) << endl;
41         return -1;
42     }
43     cout << "create socket fd " << iSockFd << endl;
44
45     sockaddr_in oServerAddr;
46     memset(&oServerAddr, 0, sizeof(oServerAddr));
47     oServerAddr.sin_family = AF_INET;
48     oServerAddr.sin_addr.s_addr = iIp;
49     oServerAddr.sin_port = htons(usPort);
50     if (connect(iSockFd, (sockaddr *)&oServerAddr, sizeof(oServerAddr)) < 0)
51     {
52         cerr << "fail to connect to " << szIp << ":" << usPort << ", err: " << strerror(errno) << endl;
53         return -1;
54     }
55     cout << "connect to " << szIp << ":" << usPort << endl;
56
57     ssize_t iSendLen = send(iSockFd, szMsg, uiMsgLen, 0);
58     if (iSendLen < 0)
59     {
60         cerr << "fail to send, err: " << strerror(errno) << endl;
61         return -1;
62     }
63     cout << "send len: " << iSendLen << ", msg: " << szMsg << endl;
64
65     char szRecvBuf[1024 * 1024];
66     char *pRecvBuf = szRecvBuf;
67     size_t uiBufLen = sizeof(szRecvBuf);
68     size_t uiRecvTotal = 0;
69     while (uiRecvTotal < iSendLen)
70     {
71         ssize_t iRecvLen = recv(iSockFd, pRecvBuf, uiBufLen, 0);
72         if (iRecvLen < 0)
73         {
74             cerr << "fail to recv, close connection, err: " << strerror(errno) << endl;
75             close(iSockFd);
76             return -1;
77         }
78         if (iRecvLen == 0)
79         {
80             cout << "connection closed by server" << endl;
81             close(iSockFd);
82             break;
83         }
84         pRecvBuf += iRecvLen;
85         uiBufLen -= iRecvLen;
86         uiRecvTotal += iRecvLen;
87     }
88     szRecvBuf[uiRecvTotal] = ‘\0‘;
89     cout << "recv len: " << uiRecvTotal << ", msg: " << szRecvBuf << endl;
90     close(iSockFd);
91
92     return 0;
93 }