nptl/pthread_key_delete.c

   1 /* Copyright (C) 2002-2023 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include "pthreadP.h"
  20 #include <atomic.h>
  21 #include <shlib-compat.h>
  22
  23 int
  24 ___pthread_key_delete (pthread_key_t key)
  25 {
  26   int result = EINVAL;
  27
  28   if (__glibc_likely (key < PTHREAD_KEYS_MAX))
  29     {
  30       unsigned int seq = __pthread_keys[key].seq;
  31
  32       if (__builtin_expect (! KEY_UNUSED (seq), 1)
  33           && ! atomic_compare_and_exchange_bool_acq (&__pthread_keys[key].seq,
  34                                                      seq + 1, seq))
  35         /* We deleted a valid key.  */
  36         result = 0;
  37     }
  38
  39   return result;
  40 }
  41 versioned_symbol (libc, ___pthread_key_delete, pthread_key_delete,
  42                   GLIBC_2_34);
  43 libc_hidden_ver (___pthread_key_delete, __pthread_key_delete)
  44 #ifndef SHARED
  45 strong_alias (___pthread_key_delete, __pthread_key_delete)
  46 #endif
  47
  48 #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_34)
  49 compat_symbol (libpthread, ___pthread_key_delete, pthread_key_delete,
  50                GLIBC_2_0);
  51 #endif