nm_connect

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define LINE_MAX 255

void print_usage() {
    fprintf(stderr,
        "Usage: <nm_connect> [Options]\n      Options:\n\t -l: list "
        "networks\n\t -c: connect <SSID>\n");

    exit(1);
}

int run_nm(char *cmd, char lines[][LINE_MAX])
{
    FILE *nm;
    char buffer[LINE_MAX];

    int cnt = 0;

    if ((nm = popen(cmd, "r")) == NULL)
        perror("popen error ....");

    while (fgets(buffer, sizeof(buffer), nm) != NULL) {
        strtok(buffer, "\n");
        strcpy(lines[cnt++], buffer);
    }

    pclose(nm);
    return cnt;
}

void connect(char *ssid, char *pass)
{
    char nmcli[] = "nmcli device wifi";
    char command[256];
    sprintf(command, "%s connect %s password %s", nmcli, ssid, pass);

    int statusCode = system(command);

    if (statusCode == 0) {
        fprintf(stdout, "connected on %s wifi ssid\n", ssid);
    } else {
        fprintf(stderr, "nmcli command error...");

    }
}

int main(int argc, char *argv[])
{
    int option;
    char ssid[15];
    char pass[10];
    int lflag = 0;
    int cflag = 0;
    char out[100][LINE_MAX];
    char comm_nm[LINE_MAX] = "nmcli device wifi";
    char cmd[LINE_MAX];

    if (argc < 2) {
        print_usage();
    }

    while ((option = getopt(argc, argv, "lhc:")) != -1) {
        switch (option) {
        case 'l':
            if (lflag) {
                print_usage();
            } else {
                lflag = 1;
            }
            sprintf(cmd, "%s list", comm_nm);
            int a = run_nm(cmd, out);
            printf("\n%55s\n\n", "Available WIFI Networks");
            for (int i = 0; i < a; ++i)
                printf("%s\n", out[i]);

            exit(EXIT_SUCCESS);
        case 'c':
            if (cflag) {
                print_usage();
            } else {
                cflag = 1;
            }
            strcpy(ssid, optarg);
            strcpy(pass, getpass("password: "));

            connect(ssid, pass);
            exit(EXIT_SUCCESS);

        case 'h':
            print_usage();
            exit(EXIT_SUCCESS);

        default:
            print_usage();
        }
    }

    if (strcmp(argv[optind],"-l") != 0 || strcmp(argv[optind], "-c") != 0 || strcmp(argv[optind], "-h") != 0) {
        fprintf(stderr, "ERROR: Expected options\n");
        puts("");
        print_usage();
    }

    return EXIT_SUCCESS;
}