1  /* Check getcontext and setcontext on the context from makecontext.
       2     Copyright (C) 2018-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <stdio.h>
      20  #include <stdlib.h>
      21  #include <ucontext.h>
      22  #include <unistd.h>
      23  #include <stdatomic.h>
      24  
      25  static ucontext_t ctx[3];
      26  static atomic_int done;
      27  
      28  static void
      29  f1 (void)
      30  {
      31    printf ("start f1\n");
      32    if (!done)
      33      {
      34        if (getcontext (&ctx[2]) != 0)
      35  	{
      36  	  printf ("%s: getcontext: %m\n", __FUNCTION__);
      37  	  exit (EXIT_FAILURE);
      38  	}
      39        if (done)
      40  	exit (EXIT_SUCCESS);
      41      }
      42    done++;
      43    if (setcontext (&ctx[2]) != 0)
      44      {
      45        printf ("%s: setcontext: %m\n", __FUNCTION__);
      46        exit (EXIT_FAILURE);
      47      }
      48  }
      49  
      50  static int
      51  do_test (void)
      52  {
      53    char st1[32768];
      54    puts ("making contexts");
      55    if (getcontext (&ctx[0]) != 0)
      56      {
      57        printf ("%s: getcontext: %m\n", __FUNCTION__);
      58        exit (EXIT_FAILURE);
      59      }
      60    if (getcontext (&ctx[1]) != 0)
      61      {
      62        printf ("%s: getcontext: %m\n", __FUNCTION__);
      63        exit (EXIT_FAILURE);
      64      }
      65    ctx[1].uc_stack.ss_sp = st1;
      66    ctx[1].uc_stack.ss_size = sizeof st1;
      67    ctx[1].uc_link = &ctx[0];
      68    makecontext (&ctx[1], (void (*) (void)) f1, 0);
      69    if (setcontext (&ctx[1]) != 0)
      70      {
      71        printf ("%s: setcontext: %m\n", __FUNCTION__);
      72        exit (EXIT_FAILURE);
      73      }
      74    exit (EXIT_FAILURE);
      75  }
      76  
      77  #include <support/test-driver.c>