nptl/pthread_attr_init.c

   1 /* Copyright (C) 2002-2020 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
   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 <errno.h>
  20 #include <string.h>
  21 #include <unistd.h>
  22 #include "pthreadP.h"
  23
  24 #include <shlib-compat.h>
  25
  26
  27 struct pthread_attr *__attr_list;
  28 int __attr_list_lock = LLL_LOCK_INITIALIZER;
  29
  30
  31 int
  32 __pthread_attr_init (pthread_attr_t *attr)
  33 {
  34   struct pthread_attr *iattr;
  35
  36   ASSERT_TYPE_SIZE (pthread_attr_t, __SIZEOF_PTHREAD_ATTR_T);
  37   ASSERT_PTHREAD_INTERNAL_SIZE (pthread_attr_t, struct pthread_attr);
  38
  39   /* Many elements are initialized to zero so let us do it all at
  40      once.  This also takes care of clearing the bytes which are not
  41      internally used.  */
  42   memset (attr, '\0', __SIZEOF_PTHREAD_ATTR_T);
  43
  44   iattr = (struct pthread_attr *) attr;
  45
  46   /* Default guard size specified by the standard.  */
  47   iattr->guardsize = __getpagesize ();
  48
  49   return 0;
  50 }
  51 libc_hidden_def (__pthread_attr_init)
  52 versioned_symbol (libc, __pthread_attr_init, pthread_attr_init, GLIBC_2_1);
  53
  54
  55 #if SHLIB_COMPAT(libc, GLIBC_2_0, GLIBC_2_1)
  56 int
  57 __pthread_attr_init_2_0 (pthread_attr_t *attr)
  58 {
  59   /* This code is specific to the old LinuxThread code which has a too
  60      small pthread_attr_t definition.  The struct looked like
  61      this:  */
  62   struct old_attr
  63   {
  64     int detachstate;
  65     int schedpolicy;
  66     struct sched_param schedparam;
  67     int inheritsched;
  68     int scope;
  69   };
  70   struct pthread_attr *iattr;
  71
  72   /* Many elements are initialized to zero so let us do it all at
  73      once.  This also takes care of clearing the bytes which are not
  74      internally used.  */
  75   memset (attr, '\0', sizeof (struct old_attr));
  76
  77   iattr = (struct pthread_attr *) attr;
  78   iattr->flags |= ATTR_FLAG_OLDATTR;
  79
  80   /* We cannot enqueue the attribute because that member is not in the
  81      old attribute structure.  */
  82   return 0;
  83 }
  84 compat_symbol (libc, __pthread_attr_init_2_0, pthread_attr_init, GLIBC_2_0);
  85 #endif