/* Copyright (C) 2006-2018 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 <errno.h>

#include <stdlib.h>

#include <stdio.h>

#include <ucontext.h>

#include <assert.h>

#include <unwind.h>

#include <dlfcn.h>

#include <gnu/lib-names.h>

ucontext_t ucp;

char st1[16384];

__thread int thr;

int somevar = -76;

long othervar = -78L;

struct trace_arg

{

  int cnt, size;

};

static _Unwind_Reason_Code

backtrace_helper (struct _Unwind_Context *ctx, void *a)

{

  struct trace_arg *arg = a;

  if (++arg->cnt == arg->size)

    return _URC_END_OF_STACK;

  return _URC_NO_REASON;

}

void

cf (int i)

{

  struct trace_arg arg = { .size = 100, .cnt = -1 };

  void *handle;

  _Unwind_Reason_Code (*unwind_backtrace) (_Unwind_Trace_Fn, void *);

  if (i != othervar || thr != 94)

    {

      printf ("i %d thr %d\n", i, thr);

      exit (1);

    }

  /* Test if callback function of _Unwind_Backtrace is not called infinitely

     times. See Bug 18508 or gcc bug "Bug 66303 - runtime.Caller() returns

     infinitely deep stack frames on s390x.".

     The go runtime calls backtrace_full() in

     <gcc-src>/libbacktrace/backtrace.c, which uses _Unwind_Backtrace().  */

  handle = dlopen (LIBGCC_S_SO, RTLD_LAZY);

  if (handle != NULL)

    {

      unwind_backtrace = dlsym (handle, "_Unwind_Backtrace");

      if (unwind_backtrace != NULL)

	{

	  unwind_backtrace (backtrace_helper, &arg;;

	  assert (arg.cnt != -1 && arg.cnt < 100);

	}

      dlclose (handle);

    }

  /* Since uc_link below has been set to NULL, setcontext is supposed to

     terminate the process normally after this function returns.  */

}

int

do_test (void)

{

  if (getcontext (&ucp) != 0)

    {

      if (errno == ENOSYS)

	{

	  puts ("context handling not supported");

	  return 0;

	}

      puts ("getcontext failed");

      return 1;

    }

  thr = 94;

  ucp.uc_link = NULL;

  ucp.uc_stack.ss_sp = st1;

  ucp.uc_stack.ss_size = sizeof st1;

  makecontext (&ucp, (void (*) (void)) cf, 1, somevar - 2);

  if (setcontext (&ucp) != 0)

    {

      puts ("setcontext failed");

      return 1;

    }

  return 2;

}

#define TEST_FUNCTION do_test ()

#include "../test-skeleton.c"