/* Multi-threaded test for resolver initialization.

   Copyright (C) 2017-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <netdb.h>

#include <resolv.h>

#include <stdlib.h>

#include <support/check.h>

#include <support/support.h>

#include <support/xthread.h>

/* Whether name lookups succeed does not really matter.  We use this

   to trigger initialization of the resolver.  */

static const char *test_hostname = "www.gnu.org";

/* The different initialization methods.  */

enum test_type { init, byname, gai };

enum { type_count = 3 };

/* Thread function.  Perform a few resolver options.  */

static void *

thread_func (void *closure)

{

  enum test_type *ptype = closure;

  /* Perform a few calls to the requested operation.  */

  TEST_VERIFY (*ptype >= 0);

  TEST_VERIFY (*ptype < (int) type_count);

  for (int i = 0; i < 3; ++i)

    switch (*ptype)

      {

      case init:

	res_init ();

	break;

      case byname:

	gethostbyname (test_hostname);

	break;

      case gai:

	{

	  struct addrinfo hints = { 0, };

	  struct addrinfo *ai = NULL;

	  if (getaddrinfo (test_hostname, "80", &hints, &ai) == 0)

	    freeaddrinfo (ai);

	}

	break;

      }

  free (ptype);

  return NULL;

}

static int

do_test (void)

{

  /* Start a small number of threads which perform resolver

     operations.  */

  enum { thread_count = 30 };

  pthread_t threads[thread_count];

  for (int i = 0; i < thread_count; ++i)

    {

      enum test_type *ptype = xmalloc (sizeof (*ptype));

      *ptype = i % type_count;

      threads[i] = xpthread_create (NULL, thread_func, ptype);

    }

  for (int i = 0; i < type_count; ++i)

    {

      enum test_type *ptype = xmalloc (sizeof (*ptype));

      *ptype = i;

      thread_func (ptype);

    }

  for (int i = 0; i < thread_count; ++i)

    xpthread_join (threads[i]);

  return 0;

}

#include <support/test-driver.c>