// Server

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

#define PORT 8080

void* handle_client(void* arg) {
    int client_sockfd = *(int*)arg;
    free(arg);

    char buff[1024];
    read(client_sockfd, buff, 1024);

    if(strcmp(buff, "cpuinfo") == 0) {
        FILE* fp = fopen("/proc/cpuinfo", "r");
        char cpuinfo[1024];
        fread(cpuinfo, 1, 1024, fp);
        fclose(fp);

        write(client_sockfd, cpuinfo, strlen(cpuinfo)+1);

    } else if(strcmp(buff, "meminfo") == 0) {
        FILE* fp = fopen("/proc/meminfo", "r");
        char meminfo[1024];
        fread(meminfo, 1, 1024, fp);
        fclose(fp);

        write(client_sockfd, meminfo, strlen(meminfo)+1);

    } else if(strcmp(buff, "lspci") == 0) {
        FILE* fp = popen("lspci", "r");
        char lspci[1024];
        fread(lspci, 1, 1024, fp);
        pclose(fp);

        write(client_sockfd, lspci, strlen(lspci)+1);
    }

    close(client_sockfd);
}

int main() {
    int server_sockfd, client_sockfd;
    struct sockaddr_in server_addr, client_addr;
    socklen_t addr_size;
    pthread_t tid;

    server_sockfd = socket(AF_INET, SOCK_STREAM, 0);

    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(PORT);
    server_addr.sin_addr.s_addr = INADDR_ANY;

    bind(server_sockfd, (struct sockaddr*)&server_addr, sizeof(server_addr));

    listen(server_sockfd, 5);

    while(1) {
        addr_size = sizeof(client_addr);
        client_sockfd = accept(server_sockfd, (struct sockaddr*)&client_addr, &addr_size);

        int* p_client_sockfd = malloc(sizeof(int));
        *p_client_sockfd = client_sockfd;

        pthread_create(&tid, NULL, handle_client, (void*)p_client_sockfd);
    }

    return 0;
}

// Client

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

#define PORT 8080

int main() {

    char buff[1024];
    int sockfd;
    struct sockaddr_in server_addr;

    sockfd = socket(AF_INET, SOCK_STREAM, 0);

    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(PORT);
    server_addr.sin_addr.s_addr = INADDR_ANY;

    connect(sockfd, (struct sockaddr*)&server_addr, sizeof(server_addr));

    puts("1. CPU Info");
    puts("2. Memory Info");
    puts("3. PCI Devices");

    printf("Option: ");
    fgets(buff, sizeof(buff), stdin);
    buff[strlen(buff)-1] = '\0';

    if(strcmp(buff,"1") == 0) {
       strcpy(buff,"cpuinfo");
    } else if(strcmp(buff,"2") == 0) {
       strcpy(buff,"meminfo");
    } else if(strcmp(buff,"3") == 0) {
       strcpy(buff,"lspci");
    }

    send(sockfd, buff, strlen(buff), 0);
    recv(sockfd, buff, 1024, 0);

    puts(buff);

    close(sockfd);

    return 0;
}