实现TCP的C代码封装（含代码）

tcp_socket.h：

复制#ifndef TCP_SCOKET_H #define TCP_SCOKET_H #include #include #include #include #include #include #include #include #include #define MAX_CONNECT_NUM 10 int tcp_init(const char* ip, int port); int tcp_accept(int sfd); int tcp_connect(const char* ip, int port); int tcp_nonblocking_recv(int conn_sockfd, void *rx_buf, int buf_len, int timeval_sec, int timeval_usec); int tcp_blocking_recv(int conn_sockfd, void *rx_buf, uint16_t buf_len); int tcp_send(int conn_sockfd, uint8_t *tx_buf, uint16_t buf_len); void tcp_close(int sockfd); #endif

tcp_socket.c：

复制#include “tcp_socket.h” int tcp_init(const char* ip, int port) { int optval = 1; int server_fd = socket(AF_INET, SOCK_STREAM, 0); if (server_fd < 0) { perror(“socket”); return -1; } /* 解除端口占用 */ if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval)) < 0) { perror(“setsockoptn”); return -1; } struct sockaddr_in server_addr; bzero(&server_addr, sizeof(struct sockaddr)); server_addr.sin_family = AF_INET; server_addr.sin_port = htons(port); if (NULL == ip) { server_addr.sin_addr.s_addr = htonl(INADDR_ANY); } else { server_addr.sin_addr.s_addr = inet_addr(ip); } if (bind(server_fd, (struct sockaddr*)&server_addr,sizeof(struct sockaddr)) < 0) { perror(“bind”); close(server_fd); return -1; } if(listen(server_fd, MAX_CONNECT_NUM) < 0) { perror(“listen”); close(server_fd); return -1; } return server_fd; } int tcp_accept(int server_fd) { struct sockaddr_in client_addr = {0}; int addrlen = sizeof(struct sockaddr); int new_fd = accept(server_fd, (struct sockaddr*) &client_addr, &addrlen); if(new_fd < 0) { perror(“accept”); close(server_fd); return -1; } return new_fd; } int tcp_connect(const char *ip, int port) { int server_fd = socket(AF_INET, SOCK_STREAM, 0); if (server_fd < 0) { perror(“socket”); return -1; } struct sockaddr_in server_addr; bzero(&server_addr, sizeof(struct sockaddr)); server_addr.sin_family = AF_INET; server_addr.sin_port = htons(port); server_addr.sin_addr.s_addr = inet_addr(ip); if (connect(server_fd, (struct sockaddr*)&server_addr, sizeof(struct sockaddr)) < 0) { perror(“connect”); close(server_fd); return -1; } return server_fd; } int tcp_nonblocking_recv(int conn_sockfd, void *rx_buf, int buf_len, int timeval_sec, int timeval_usec) { fd_set readset; struct timeval timeout = {0, 0}; int maxfd = 0; int fp0 = 0; int recv_bytes = 0; int ret = 0; timeout.tv_sec = timeval_sec; timeout.tv_usec = timeval_usec; FD_ZERO(&readset); FD_SET(conn_sockfd, &readset); maxfd = conn_sockfd > fp0 ? (conn_sockfd+1) : (fp0+1); ret = select(maxfd, &readset, NULL, NULL, &timeout); if (ret > 0) { if (FD_ISSET(conn_sockfd, &readset)) { if ((recv_bytes = recv(conn_sockfd, rx_buf, buf_len, MSG_DONTWAIT))== -1) { perror(“recv”); return -1; } } } else { return -1; } return recv_bytes; } int tcp_blocking_recv(int conn_sockfd, void *rx_buf, uint16_t buf_len) { return recv(conn_sockfd, rx_buf, buf_len, 0); } int tcp_send(int conn_sockfd, uint8_t *tx_buf, uint16_t buf_len) { return send(conn_sockfd, tx_buf, buf_len, 0); } void tcp_close(int sockfd) { close(sockfd); }

x下面测试代码：

复制#include “tcp_socket.h” int main(int argc, char **argv) { printf(“==================tcp server==================n”); int server_fd = tcp_init(NULL, 4321); if (server_fd < 0) { printf(“tcp_init error!n”); exit(EXIT_FAILURE); } int client_fd = tcp_accept(server_fd); if (client_fd < 0) { printf(“tcp_accept error!n”); exit(EXIT_FAILURE); } while (1) { char buf[128] = {0}; int recv_len = tcp_blocking_recv(client_fd, buf, sizeof(buf)); if (recv_len <= 0) { printf(“recv error!n”); tcp_close(client_fd); tcp_close(server_fd); exit(EXIT_FAILURE); } printf(“recv : %sn”, buf); int send_len = tcp_send(client_fd, buf, strlen(buf)); if (send_len <= 0) { printf(“send error!n”); tcp_close(client_fd); tcp_close(server_fd); exit(EXIT_FAILURE); } else { printf(“send success! send: %s, send_len: %dn”, buf, send_len); } } tcp_close(server_fd); return 0; }

tcp_client.c：

复制#include “tcp_socket.h” int main(int argc, char **argv) { printf(“==================tcp cient==================n”); if (argc < 3) { printf(“usage:./tcp_client ip portn”); exit(EXIT_FAILURE); } char ip_buf[32] = {0}; int port = 0; memcpy(ip_buf, argv[1], strlen(argv[1])); port = atoi(argv[2]); int server_fd = tcp_connect(ip_buf, port); if (server_fd < 0) { printf(“tcp_connect error!n”); exit(EXIT_FAILURE); } while (1) { char buf[128] = {0}; if (scanf(“%s”, buf)) { int send_len = tcp_send(server_fd, buf, strlen(buf)); if (send_len <= 0) { printf(“tcp_send error!n”); tcp_close(server_fd); exit(EXIT_FAILURE); } else { printf(“send success! send: %s, send_len: %dn”, buf, send_len); } bzero(buf, sizeof(buf)); int recv_len = tcp_blocking_recv(server_fd, buf, sizeof(buf)); if (recv_len <= 0) { printf(“tcp_blocking_recv error!n”); tcp_close(server_fd); exit(EXIT_FAILURE); } printf(“recv : %sn”, buf); } } return 0; }