text: /*
   * Copyright 2016-2019 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the OpenSSL license (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <openssl/crypto.h>
  #include "internal/cryptlib.h"
  
  #if defined(OPENSSL_THREADS) && !defined(CRYPTO_TDEBUG) && !defined(OPENSSL_SYS_WINDOWS)
  
  # if defined(OPENSSL_SYS_UNIX)
  #  include <sys/types.h>
  #  include <unistd.h>
  #endif
  
  # ifdef PTHREAD_RWLOCK_INITIALIZER
  #  define USE_RWLOCK
  # endif
  
  CRYPTO_RWLOCK *CRYPTO_THREAD_lock_new(void)
  {
  # ifdef USE_RWLOCK
      CRYPTO_RWLOCK *lock;
  
      if ((lock = OPENSSL_zalloc(sizeof(pthread_rwlock_t))) == NULL) {
          /* Don't set error, to avoid recursion blowup. */
          return NULL;
      }
  
      if (pthread_rwlock_init(lock, NULL) != 0) {
          OPENSSL_free(lock);
          return NULL;
      }
  # else
      pthread_mutexattr_t attr;
      CRYPTO_RWLOCK *lock;
  
      if ((lock = OPENSSL_zalloc(sizeof(pthread_mutex_t))) == NULL) {
          /* Don't set error, to avoid recursion blowup. */
          return NULL;
      }
  
      pthread_mutexattr_init( &attr );
  #if defined(__TANDEM) && defined(_SPT_MODEL_)
      pthread_mutexattr_setkind_np( &attr, MUTEX_RECURSIVE_NP );
  #else
      pthread_mutexattr_settype( &attr, PTHREAD_MUTEX_RECURSIVE );
  #endif
  
      if (pthread_mutex_init(lock, &attr) != 0) {
          pthread_mutexattr_destroy(&attr);
          OPENSSL_free(lock);
          return NULL;
      }
  
      pthread_mutexattr_destroy(&attr);
  # endif
  
      return lock;
  }
  
  int CRYPTO_THREAD_read_lock(CRYPTO_RWLOCK *lock)
  {
  # ifdef USE_RWLOCK
      if (pthread_rwlock_rdlock(lock) != 0)
          return 0;
  # else
      if (pthread_mutex_lock(lock) != 0)
          return 0;
  # endif
  
      return 1;
  }
  
  int CRYPTO_THREAD_write_lock(CRYPTO_RWLOCK *lock)
  {
  # ifdef USE_RWLOCK
      if (pthread_rwlock_wrlock(lock) != 0)
          return 0;
  # else
      if (pthread_mutex_lock(lock) != 0)
          return 0;
  # endif
  
      return 1;
  }
  
  int CRYPTO_THREAD_unlock(CRYPTO_RWLOCK *lock)
  {
  # ifdef USE_RWLOCK
      if (pthread_rwlock_unlock(lock) != 0)
          return 0;
  # else
      if (pthread_mutex_unlock(lock) != 0)
          return 0;
  # endif
  
      return 1;
  }
  
  void CRYPTO_THREAD_lock_free(CRYPTO_RWLOCK *lock)
  {
      if (lock == NULL)
          return;
  
  # ifdef USE_RWLOCK
      pthread_rwlock_destroy(lock);
  # else
      pthread_mutex_destroy(lock);
  # endif
      OPENSSL_free(lock);
  
      return;
  }
  
  int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
  {
      if (pthread_once(once, init) != 0)
          return 0;
  
      return 1;
  }
  
  int CRYPTO_THREAD_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))
  {
      if (pthread_key_create(key, cleanup) != 0)
          return 0;
  
      return 1;
  }
  
  void *CRYPTO_THREAD_get_local(CRYPTO_THREAD_LOCAL *key)
  {
      return pthread_getspecific(*key);
  }
  
  int CRYPTO_THREAD_set_local(CRYPTO_THREAD_LOCAL *key, void *val)
  {
      if (pthread_setspecific(*key, val) != 0)
          return 0;
  
      return 1;
  }
  
  int CRYPTO_THREAD_cleanup_local(CRYPTO_THREAD_LOCAL *key)
  {
      if (pthread_key_delete(*key) != 0)
          return 0;
  
      return 1;
  }
  
  CRYPTO_THREAD_ID CRYPTO_THREAD_get_current_id(void)
  {
      return pthread_self();
  }
  
  int CRYPTO_THREAD_compare_id(CRYPTO_THREAD_ID a, CRYPTO_THREAD_ID b)
  {
      return pthread_equal(a, b);
  }
  
  int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
  {
  # if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL)
      if (__atomic_is_lock_free(sizeof(*val), val)) {
          *ret = __atomic_add_fetch(val, amount, __ATOMIC_ACQ_REL);
          return 1;
      }
  # endif
      if (!CRYPTO_THREAD_write_lock(lock))
          return 0;
  
      *val += amount;
      *ret  = *val;
  
      if (!CRYPTO_THREAD_unlock(lock))
          return 0;
  
      return 1;
  }
  
  # ifdef OPENSSL_SYS_UNIX
  static pthread_once_t fork_once_control = PTHREAD_ONCE_INIT;
  
  static void fork_once_func(void)
  {
      pthread_atfork(OPENSSL_fork_prepare,
                     OPENSSL_fork_parent, OPENSSL_fork_child);
  }
  # endif
  
  int openssl_init_fork_handlers(void)
  {
  # ifdef OPENSSL_SYS_UNIX
      if (pthread_once(&fork_once_control, fork_once_func) == 0)
          return 1;
  # endif
      return 0;
  }
  
  int openssl_get_fork_id(void)
  {
      return getpid();
  }
  #endif
  