NetworkManager/examples/C/glib/list-connections-libnm.c

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2011 Red Hat, Inc.
 */

/*
 * The example shows how to list connections.  Contrast this example with
 * list-connections-gdbus.c, which is a bit lower level and talks directly to NM
 * using GDBus.
 *
 * Compile with:
 *   gcc -Wall list-connections-libnm.c -o list-connections-libnm `pkg-config --cflags --libs libnm`
 */

#include <glib.h>
#include <stdio.h>
#include <stdlib.h>

#include <NetworkManager.h>

/* Print details of connection */
static void
show_connection(NMConnection *connection)
{
    NMSettingConnection *s_con;
    guint64              timestamp;
    char                *timestamp_str;
    char                 timestamp_real_str[64];
    const char          *val1, *val2, *val3, *val4, *val5;

    s_con = nm_connection_get_setting_connection(connection);
    if (s_con) {
        struct tm localtime_data;

        /* Get various info from NMSettingConnection and show it */
        timestamp     = nm_setting_connection_get_timestamp(s_con);
        timestamp_str = g_strdup_printf("%" G_GUINT64_FORMAT, timestamp);
        strftime(timestamp_real_str,
                 sizeof(timestamp_real_str),
                 "%c",
                 localtime_r((time_t *) &timestamp, &localtime_data));

        val1 = nm_setting_connection_get_id(s_con);
        val2 = nm_setting_connection_get_uuid(s_con);
        val3 = nm_setting_connection_get_connection_type(s_con);
        val4 = nm_connection_get_path(connection);
        val5 = timestamp ? timestamp_real_str : "never";

        printf("%-25s | %s | %-15s | %-43s | %s\n", val1, val2, val3, val4, val5);

        g_free(timestamp_str);
    }
}

int
main(int argc, char *argv[])
{
    NMClient        *client;
    GError          *error = NULL;
    const GPtrArray *connections;
    int              i;

    if (!(client = nm_client_new(NULL, &error))) {
        g_message("Error: Could not connect to NetworkManager: %s.", error->message);
        g_error_free(error);
        return EXIT_FAILURE;
    }

    if (!nm_client_get_nm_running(client)) {
        g_message("Error: Can't obtain connections: NetworkManager is not running.");
        return EXIT_FAILURE;
    }

    /* Now the connections can be listed. */
    connections = nm_client_get_connections(client);

    printf("Connections:\n===================\n");

    for (i = 0; i < connections->len; i++)
        show_connection(connections->pdata[i]);

    g_object_unref(client);

    return EXIT_SUCCESS;
}