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 "pthreadP.h"
      19  #include <string.h>
      20  #include <pthread-offsets.h>
      21  #include <shlib-compat.h>
      22  
      23  static const struct pthread_rwlockattr default_rwlockattr =
      24    {
      25      .lockkind = PTHREAD_RWLOCK_DEFAULT_NP,
      26      .pshared = PTHREAD_PROCESS_PRIVATE
      27    };
      28  
      29  
      30  /* See pthread_rwlock_common.c.  */
      31  int
      32  ___pthread_rwlock_init (pthread_rwlock_t *rwlock,
      33  		       const pthread_rwlockattr_t *attr)
      34  {
      35    ASSERT_TYPE_SIZE (pthread_rwlock_t, __SIZEOF_PTHREAD_RWLOCK_T);
      36  
      37    /* The __flags is the only field where its offset should be checked to
      38       avoid ABI breakage with static initializers.  */
      39    ASSERT_PTHREAD_INTERNAL_OFFSET (pthread_rwlock_t, __data.__flags,
      40  				  __PTHREAD_RWLOCK_FLAGS_OFFSET);
      41    ASSERT_PTHREAD_INTERNAL_MEMBER_SIZE (pthread_rwlock_t, __data.__flags,
      42  				       int);
      43  
      44    const struct pthread_rwlockattr *iattr;
      45  
      46    iattr = ((const struct pthread_rwlockattr *) attr) ?: &default_rwlockattr;
      47  
      48    memset (rwlock, '\0', sizeof (*rwlock));
      49  
      50    rwlock->__data.__flags = iattr->lockkind;
      51  
      52    /* The value of __SHARED in a private rwlock must be zero.  */
      53    rwlock->__data.__shared = (iattr->pshared != PTHREAD_PROCESS_PRIVATE);
      54  
      55    return 0;
      56  }
      57  versioned_symbol (libc, ___pthread_rwlock_init, pthread_rwlock_init,
      58                    GLIBC_2_34);
      59  libc_hidden_ver (___pthread_rwlock_init, __pthread_rwlock_init)
      60  #ifndef SHARED
      61  strong_alias (___pthread_rwlock_init, __pthread_rwlock_init)
      62  #endif
      63  
      64  #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_1, GLIBC_2_34)
      65  compat_symbol (libpthread, ___pthread_rwlock_init, pthread_rwlock_init,
      66                 GLIBC_2_1);
      67  #endif
      68  #if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_2, GLIBC_2_34)
      69  compat_symbol (libpthread, ___pthread_rwlock_init, __pthread_rwlock_init,
      70                 GLIBC_2_2);
      71  #endif