实验四 Web服务器1-socket编程

time服务器的客户端服务器

time_server.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>

void handle_client(int client_socket) {
    time_t current_time;
    char time_string[50];
    
    // Get current time
    time(&current_time);
    snprintf(time_string, sizeof(time_string), "%s", ctime(&current_time));

    // Send current time to the client
    send(client_socket, time_string, strlen(time_string), 0);

    close(client_socket);
}

int main() {
    int server_socket, client_socket;
    struct sockaddr_in server_addr, client_addr;
    socklen_t client_addr_len = sizeof(client_addr);

    // Create socket
    server_socket = socket(AF_INET, SOCK_STREAM, 0);
    if (server_socket == -1) {
        perror("Error creating socket");
        exit(EXIT_FAILURE);
    }

    // Bind socket to address and port
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = INADDR_ANY;
    server_addr.sin_port = htons(12345); // Use a specific port number, e.g., 12345

    if (bind(server_socket, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1) {
        perror("Error binding socket");
        exit(EXIT_FAILURE);
    }

    // Listen for incoming connections
    if (listen(server_socket, 5) == -1) {
        perror("Error listening for connections");
        exit(EXIT_FAILURE);
    }

    printf("Time Server listening on port 12345...\n");

    while (1) {
        // Accept connection from client
        client_socket = accept(server_socket, (struct sockaddr*)&client_addr, &client_addr_len);
        if (client_socket == -1) {
            perror("Error accepting connection");
            continue;
        }

        printf("Accepted connection from %s:%d\n", inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));

        // Fork a child process to handle the client
        if (fork() == 0) {
            // Child process
            close(server_socket);  // Close server socket in child process
            handle_client(client_socket);
            exit(EXIT_SUCCESS);
        } else {
            // Parent process
            close(client_socket);  // Close client socket in parent process
            waitpid(-1, NULL, WNOHANG);  // Reap zombie processes
        }
    }

    return 0;
}

time_client.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

void time_client() {
    int client_socket = socket(AF_INET, SOCK_STREAM, 0);
    if (client_socket == -1) {
        perror("Error creating socket");
        exit(EXIT_FAILURE);
    }

    struct sockaddr_in server_addr;
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = inet_addr("127.0.0.1"); // Replace with your server's IP address
    server_addr.sin_port = htons(12345); // Use the port number used by the time server

    if (connect(client_socket, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1) {
        perror("Error connecting to the server");
        close(client_socket);
        exit(EXIT_FAILURE);
    }

    char buffer[1024];
    ssize_t recv_size = recv(client_socket, buffer, sizeof(buffer) - 1, 0);
    if (recv_size <= 0) {
        perror("Error receiving data");
    } else {
        buffer[recv_size] = '\0'; // Null-terminate the received data
        printf("Time from server: %s", buffer);
    }

    close(client_socket);
}

int main() {
    // Time Client
    printf("Time Client:\n");
    time_client();

    return 0;
}

echo服务器的客户端服务器

echo_server.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h>

void handle_echo(int client_socket) {
    char buffer[1024];
    int pid = getpid();
    char student_id[] = "20211327";
    char name[] = "sjx";

    // Receive data from client
    ssize_t recv_size = recv(client_socket, buffer, sizeof(buffer), 0);
    if (recv_size <= 0) {
        perror("Error receiving data");
        close(client_socket);
        return;
    }

    // Process data and prepare response
    char response[1024];
    int snprintf_result = snprintf(response, sizeof(response), "Server process pid %d %s %s echo: %s",
                                   pid, student_id, name, buffer);

    if (snprintf_result < 0 || snprintf_result >= sizeof(response)) {
        // Handle error or truncate situation
        perror("Error formatting response");
        close(client_socket);
        return;
    }

    // Send response to the client
    send(client_socket, response, strlen(response), 0);

    close(client_socket);
}

int main() {
    int server_socket, client_socket;
    struct sockaddr_in server_addr, client_addr;
    socklen_t client_addr_len = sizeof(client_addr);

    // Create socket
    server_socket = socket(AF_INET, SOCK_STREAM, 0);
    if (server_socket == -1) {
        perror("Error creating socket");
        exit(EXIT_FAILURE);
    }

    // Bind socket to address and port
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = INADDR_ANY;
    server_addr.sin_port = htons(12346); // Use a different port number, e.g., 12346

    if (bind(server_socket, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1) {
        perror("Error binding socket");
        exit(EXIT_FAILURE);
    }

    // Listen for incoming connections
    if (listen(server_socket, 5) == -1) {
        perror("Error listening for connections");
        exit(EXIT_FAILURE);
    }

    printf("Echo Server listening on port 12346...\n");

    while (1) {
        // Accept connection from client
        client_socket = accept(server_socket, (struct sockaddr*)&client_addr, &client_addr_len);
        if (client_socket == -1) {
            perror("Error accepting connection");
            continue;
        }

        printf("Accepted connection from %s:%d\n", inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));

        // Fork a child process to handle the client
        if (fork() == 0) {
            // Child process
            close(server_socket);  // Close server socket in child process
            handle_echo(client_socket);
            exit(EXIT_SUCCESS);
        } else {
            // Parent process
            close(client_socket);  // Close client socket in parent process
            waitpid(-1, NULL, WNOHANG);  // Reap zombie processes
        }
    }

    return 0;
}

echo_client.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>

void echo_client() {
    int client_socket = socket(AF_INET, SOCK_STREAM, 0);
    if (client_socket == -1) {
        perror("Error creating socket");
        exit(EXIT_FAILURE);
    }

    struct sockaddr_in server_addr;
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = inet_addr("127.0.0.1"); // Replace with your server's IP address
    server_addr.sin_port = htons(12346); // Use the port number used by the echo server

    if (connect(client_socket, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1) {
        perror("Error connecting to the server");
        close(client_socket);
        exit(EXIT_FAILURE);
    }

    char message[] = "Hello, server!"; // Replace with your message
    send(client_socket, message, strlen(message), 0);

    char buffer[1024];
    ssize_t recv_size = recv(client_socket, buffer, sizeof(buffer) - 1, 0);
    if (recv_size <= 0) {
        perror("Error receiving data");
    } else {
        buffer[recv_size] = '\0'; // Null-terminate the received data
        printf("Response from server: %s\n", buffer);
    }

    close(client_socket);
}

int main() {
    // Echo Client
    printf("\nEcho Client:\n");
    echo_client();

    return 0;
}