resource_monitoring_agent.c

#include <stdio.h>
#include <sys/types.h>
#include <sys/sysinfo.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/socket.h>

double get_cpu_utilization() {
    unsigned long long totalUser, totalNice, totalSys, totalIdle, totalIOWait, totalIrq, totalSoftirq, total;
    FILE* file = fopen("/proc/stat", "r");
    fscanf(file, "cpu %llu %llu %llu %llu %llu %llu %llu", &totalUser, &totalNice,
           &totalSys, &totalIdle, &totalIOWait, &totalIrq, &totalSoftirq);
    fclose(file);

    total = totalUser + totalNice + totalSys + totalIdle + totalIOWait + totalIrq + totalSoftirq;

    return 100.0 - ((totalIdle * 100.0) / total);
}

long long get_free_memory() {
    struct sysinfo mem_info;
    sysinfo(&mem_info);
    long long phys_mem_used = mem_info.totalram - mem_info.freeram;
    phys_mem_used *= mem_info.mem_unit;
    return phys_mem_used;
}

int main(int argc, char* argv[]) {
    long long phys_mem_used = get_free_memory();
    double cpu_util = get_cpu_utilization();
    char result[512];
    sprintf(result, "{\"cpu\":\"%f\",\"memory\":\"%ll\"}\0", cpu_util, phys_mem_used);

    if (argc == 1) {
        printf(result);
        return 0;
    }
    long socket_fd = strtol(argv[1], NULL, 10);
    send(socket_fd, result, strlen(result), 0);
    return 0;
}