1  /* A thread attribute with a small stack.
       2     Copyright (C) 2019-2023 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 <support/xthread.h>
      20  #include <allocate_once.h>
      21  
      22  static void *
      23  allocate (void *closure)
      24  {
      25    pthread_attr_t *result = malloc (sizeof (*result));
      26    xpthread_attr_init (result);
      27    support_set_small_thread_stack_size (result);
      28    return result;
      29  }
      30  
      31  static void
      32  deallocate (void *ptr, void *closure)
      33  {
      34    xpthread_attr_destroy (ptr);
      35    free (ptr);
      36  }
      37  
      38  static void *small_stack_attr;
      39  
      40  pthread_attr_t *
      41  support_small_stack_thread_attribute (void)
      42  {
      43    return allocate_once (&small_stack_attr, allocate, deallocate, NULL);
      44  }
      45  
      46  static void __attribute__ ((destructor))
      47  fini (void)
      48  {
      49    if (small_stack_attr != NULL)
      50      {
      51        deallocate (small_stack_attr, NULL);
      52        small_stack_attr = NULL;
      53      }
      54  }