c - 如何使用 polkit 库编译我的 C 程序？

Question

今天，我尝试使用 polkit - 一个应用程序级工具包，用于定义和处理允许非特权进程与特权进程通信的策略。为了更好地理解它，我尝试下载了这段代码:

#include <polkit/polkit.h>

static gboolean
on_tensec_timeout (gpointer user_data)
{
  GMainLoop *loop = user_data;
  g_print ("Ten seconds has passed. Now exiting.\n");
  g_main_loop_quit (loop);
  return FALSE;
}

static void
check_authorization_cb (PolkitAuthority *authority,
                        GAsyncResult    *res,
                        gpointer         user_data)
{
  GMainLoop *loop = user_data;
  PolkitAuthorizationResult *result;
  GError *error;

  error = NULL;
  result = polkit_authority_check_authorization_finish (authority, res, &error);
  if (error != NULL)
    {
      g_print ("Error checking authorization: %s\n", error->message);
      g_error_free (error);
    }
  else
    {
      const gchar *result_str;
      if (polkit_authorization_result_get_is_authorized (result))
        {
          result_str = "authorized";
        }
      else if (polkit_authorization_result_get_is_challenge (result))
        {
          result_str = "challenge";
        }
      else
        {
          result_str = "not authorized";
        }

      g_print ("Authorization result: %s\n", result_str);
    }

  g_print ("Authorization check has been cancelled and the dialog should now be hidden.\n"
           "This process will exit in ten seconds.\n");
  g_timeout_add (10000, on_tensec_timeout, loop);
}

static gboolean
do_cancel (GCancellable *cancellable)
{
  g_print ("Timer has expired; cancelling authorization check\n");
  g_cancellable_cancel (cancellable);
  return FALSE;
}

int
main (int argc, char *argv[])
{
  pid_t parent_pid;
  const gchar *action_id;
  GMainLoop *loop;
  PolkitSubject *subject;
  PolkitAuthority *authority;
  GCancellable *cancellable;

  g_type_init ();

  if (argc != 2)
    {
      g_printerr ("usage: %s <action_id>\n", argv[0]);
      return 1;
    }
  action_id = argv[1];

  loop = g_main_loop_new (NULL, FALSE);

  authority = polkit_authority_get_sync (NULL, NULL);

  /* Typically mechanisms will use a PolkitSystemBusName since most
   * clients communicate with the mechanism via D-Bus. However for
   * this simple example we use the process id of the calling process.
   *
   * Note that if the parent was reaped we have to be careful not to
   * check if init(1) is authorized (it always is).
   */
  parent_pid = getppid ();
  if (parent_pid == 1)
    {
      g_printerr ("Parent process was reaped by init(1)\n");
      return 1;
    }
  subject = polkit_unix_process_new (parent_pid);

  cancellable = g_cancellable_new ();

  g_print ("Will cancel authorization check in 10 seconds\n");

  /* Set up a 10 second timer to cancel the check */
  g_timeout_add (10 * 1000,
                 (GSourceFunc) do_cancel,
                 cancellable);

  polkit_authority_check_authorization (authority,
                                        subject,
                                        action_id,
                                        NULL, /* PolkitDetails */
                                        POLKIT_CHECK_AUTHORIZATION_FLAGS_ALLOW_USER_INTERACTION,
                                        cancellable,
                                        (GAsyncReadyCallback) check_authorization_cb,
                                        loop);

  g_main_loop_run (loop);

  g_object_unref (authority);
  g_object_unref (subject);
  g_object_unref (cancellable);
  g_main_loop_unref (loop);

  return 0;
}

但是当我尝试用 gcc 编译它时，我收到了这个输出:

ciao.c:35:27: fatal error: polkit/polkit.h: File o directory non esistente
compilation terminated.

Answer 1

路径 polkit/polkit.h 不在系统包含路径中。确保您已下载并安装 PolKit以便 header 和库可用。