/* Test dlopen of modules with initial-exec TLS.

   Copyright (C) 2016-2020 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

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

/* This test tries to check that surplus static TLS is not used up for

   dynamic TLS optimizations and 3*192 + 4*144 = 1152 bytes of static

   TLS is available for dlopening modules with initial-exec TLS.  It

   depends on rtld.nns=4 and rtld.optional_static_tls=512 tunable setting.  */

#include <errno.h>

#include <pthread.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

static int do_test (void);

#include <support/xthread.h>

#include <support/xdlfcn.h>

#include <support/check.h>

#include <support/test-driver.c>

/* Have some big TLS in the main exe: should not use surplus TLS.  */

__thread char maintls[1000];

static pthread_barrier_t barrier;

/* Forces multi-threaded behaviour.  */

static void *

blocked_thread_func (void *closure)

{

  xpthread_barrier_wait (&barrier);

  /* TLS load and access tests run here in the main thread.  */

  xpthread_barrier_wait (&barrier);

  return NULL;

}

static void *

load_and_access (const char *mod, const char *func)

{

  /* Load module with TLS.  */

  void *p = xdlopen (mod, RTLD_NOW);

  /* Access the TLS variable to ensure it is allocated.  */

  void (*f) (void) = (void (*) (void))xdlsym (p, func);

  f ();

  return p;

}

static int

do_test (void)

{

  void *mods[6];

  {

    int ret = pthread_barrier_init (&barrier, NULL, 2);

    if (ret != 0)

      {

        errno = ret;

        printf ("error: pthread_barrier_init: %m\n");

        exit (1);

      }

  }

  pthread_t blocked_thread = xpthread_create (NULL, blocked_thread_func, NULL);

  xpthread_barrier_wait (&barrier);

  printf ("maintls[%zu]:\t %p .. %p\n",

	   sizeof maintls, maintls, maintls + sizeof maintls);

  memset (maintls, 1, sizeof maintls);

  /* Load modules with dynamic TLS (may use surplus static TLS

     opportunistically).  */

  mods[0] = load_and_access ("tst-tls-ie-mod0.so", "access0");

  mods[1] = load_and_access ("tst-tls-ie-mod1.so", "access1");

  mods[2] = load_and_access ("tst-tls-ie-mod2.so", "access2");

  mods[3] = load_and_access ("tst-tls-ie-mod3.so", "access3");

  /* Load modules with initial-exec TLS (can only use surplus static TLS).  */

  mods[4] = load_and_access ("tst-tls-ie-mod4.so", "access4");

  mods[5] = load_and_access ("tst-tls-ie-mod5.so", "access5");

  /* Here 1152 bytes of surplus static TLS is in use and at most 512 bytes

     are available (depending on TLS optimizations).  */

  printf ("The next dlopen should fail...\n");

  void *p = dlopen ("tst-tls-ie-mod6.so", RTLD_NOW);

  if (p != NULL)

    FAIL_EXIT1 ("error: expected dlopen to fail because there is "

		"not enough surplus static TLS.\n");

  printf ("...OK failed with: %s.\n", dlerror ());

  xpthread_barrier_wait (&barrier);

  xpthread_join (blocked_thread);

  /* Close the modules.  */

  for (int i = 0; i < 6; ++i)

    xdlclose (mods[i]);

  return 0;

}