text: /*
   * Copyright 2016 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 <internal/cryptlib_int.h>
  #include <openssl/err.h>
  #include <internal/rand_int.h>
  #include <internal/bio.h>
  #include <openssl/evp.h>
  #include <internal/evp_int.h>
  #include <internal/conf.h>
  #include <internal/async.h>
  #include <internal/engine.h>
  #include <internal/comp.h>
  #include <internal/err.h>
  #include <internal/err_int.h>
  #include <internal/objects.h>
  #include <stdlib.h>
  #include <assert.h>
  #include <internal/thread_once.h>
  #include <internal/dso.h>
  #include <internal/store.h>
  
  static int stopped = 0;
  
  static void ossl_init_thread_stop(struct thread_local_inits_st *locals);
  
  static CRYPTO_THREAD_LOCAL threadstopkey;
  
  static void ossl_init_thread_stop_wrap(void *local)
  {
      ossl_init_thread_stop((struct thread_local_inits_st *)local);
  }
  
  static struct thread_local_inits_st *ossl_init_get_thread_local(int alloc)
  {
      struct thread_local_inits_st *local =
          CRYPTO_THREAD_get_local(&threadstopkey);
  
      if (local == NULL && alloc) {
          local = OPENSSL_zalloc(sizeof *local);
          if (local != NULL && !CRYPTO_THREAD_set_local(&threadstopkey, local)) {
              OPENSSL_free(local);
              return NULL;
          }
      }
      if (!alloc) {
          CRYPTO_THREAD_set_local(&threadstopkey, NULL);
      }
  
      return local;
  }
  
  typedef struct ossl_init_stop_st OPENSSL_INIT_STOP;
  struct ossl_init_stop_st {
      void (*handler)(void);
      OPENSSL_INIT_STOP *next;
  };
  
  static OPENSSL_INIT_STOP *stop_handlers = NULL;
  static CRYPTO_RWLOCK *init_lock = NULL;
  
  static CRYPTO_ONCE base = CRYPTO_ONCE_STATIC_INIT;
  static int base_inited = 0;
  DEFINE_RUN_ONCE_STATIC(ossl_init_base)
  {
  #ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_base: Setting up stop handlers\n");
  #endif
  #ifndef OPENSSL_NO_CRYPTO_MDEBUG
      ossl_malloc_setup_failures();
  #endif
      /*
       * We use a dummy thread local key here. We use the destructor to detect
       * when the thread is going to stop (where that feature is available)
       */
      CRYPTO_THREAD_init_local(&threadstopkey, ossl_init_thread_stop_wrap);
  #ifndef OPENSSL_SYS_UEFI
      atexit(OPENSSL_cleanup);
  #endif
      if ((init_lock = CRYPTO_THREAD_lock_new()) == NULL)
          return 0;
      OPENSSL_cpuid_setup();
  
      /*
       * BIG FAT WARNING!
       * Everything needed to be initialized in this function before threads
       * come along MUST happen before base_inited is set to 1, or we will
       * see race conditions.
       */
      base_inited = 1;
  
  #if !defined(OPENSSL_NO_DSO) && !defined(OPENSSL_USE_NODELETE)
  # ifdef DSO_WIN32
      {
          HMODULE handle = NULL;
          BOOL ret;
  
          /* We don't use the DSO route for WIN32 because there is a better way */
          ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
                                  | GET_MODULE_HANDLE_EX_FLAG_PIN,
                                  (void *)&base_inited, &handle);
  
          return (ret == TRUE) ? 1 : 0;
      }
  # else
      /*
       * Deliberately leak a reference to ourselves. This will force the library
       * to remain loaded until the atexit() handler is run at process exit.
       */
      {
          DSO *dso = NULL;
  
          ERR_set_mark();
          dso = DSO_dsobyaddr(&base_inited, DSO_FLAG_NO_UNLOAD_ON_FREE);
          DSO_free(dso);
          ERR_pop_to_mark();
      }
  # endif
  #endif
  
      return 1;
  }
  
  static CRYPTO_ONCE load_crypto_strings = CRYPTO_ONCE_STATIC_INIT;
  static int load_crypto_strings_inited = 0;
  DEFINE_RUN_ONCE_STATIC(ossl_init_no_load_crypto_strings)
  {
      /* Do nothing in this case */
      return 1;
  }
  
  DEFINE_RUN_ONCE_STATIC(ossl_init_load_crypto_strings)
  {
      int ret = 1;
      /*
       * OPENSSL_NO_AUTOERRINIT is provided here to prevent at compile time
       * pulling in all the error strings during static linking
       */
  #if !defined(OPENSSL_NO_ERR) && !defined(OPENSSL_NO_AUTOERRINIT)
  # ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_load_crypto_strings: "
                      "err_load_crypto_strings_int()\n");
  # endif
      ret = err_load_crypto_strings_int();
      load_crypto_strings_inited = 1;
  #endif
      return ret;
  }
  
  static CRYPTO_ONCE add_all_ciphers = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_ciphers)
  {
      /*
       * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
       * pulling in all the ciphers during static linking
       */
  #ifndef OPENSSL_NO_AUTOALGINIT
  # ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_add_all_ciphers: "
                      "openssl_add_all_ciphers_int()\n");
  # endif
      openssl_add_all_ciphers_int();
  #endif
      return 1;
  }
  
  static CRYPTO_ONCE add_all_digests = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_digests)
  {
      /*
       * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
       * pulling in all the ciphers during static linking
       */
  #ifndef OPENSSL_NO_AUTOALGINIT
  # ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_add_all_digests: "
                      "openssl_add_all_digests()\n");
  # endif
      openssl_add_all_digests_int();
  #endif
      return 1;
  }
  
  DEFINE_RUN_ONCE_STATIC(ossl_init_no_add_algs)
  {
      /* Do nothing */
      return 1;
  }
  
  static CRYPTO_ONCE config = CRYPTO_ONCE_STATIC_INIT;
  static int config_inited = 0;
  static const char *appname;
  DEFINE_RUN_ONCE_STATIC(ossl_init_config)
  {
  #ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr,
              "OPENSSL_INIT: ossl_init_config: openssl_config(%s)\n",
              appname == NULL ? "NULL" : appname);
  #endif
      openssl_config_int(appname);
      config_inited = 1;
      return 1;
  }
  DEFINE_RUN_ONCE_STATIC(ossl_init_no_config)
  {
  #ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr,
              "OPENSSL_INIT: ossl_init_config: openssl_no_config_int()\n");
  #endif
      openssl_no_config_int();
      config_inited = 1;
      return 1;
  }
  
  static CRYPTO_ONCE async = CRYPTO_ONCE_STATIC_INIT;
  static int async_inited = 0;
  DEFINE_RUN_ONCE_STATIC(ossl_init_async)
  {
  #ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_async: async_init()\n");
  #endif
      if (!async_init())
          return 0;
      async_inited = 1;
      return 1;
  }
  
  #ifndef OPENSSL_NO_ENGINE
  static CRYPTO_ONCE engine_openssl = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_openssl)
  {
  # ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_openssl: "
                      "engine_load_openssl_int()\n");
  # endif
      engine_load_openssl_int();
      return 1;
  }
  # ifndef OPENSSL_NO_DEVCRYPTOENG
  static CRYPTO_ONCE engine_devcrypto = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_devcrypto)
  {
  #  ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_devcrypto: "
                      "engine_load_devcrypto_int()\n");
  #  endif
      engine_load_devcrypto_int();
      return 1;
  }
  # endif
  
  # ifndef OPENSSL_NO_RDRAND
  static CRYPTO_ONCE engine_rdrand = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_rdrand)
  {
  #  ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_rdrand: "
                      "engine_load_rdrand_int()\n");
  #  endif
      engine_load_rdrand_int();
      return 1;
  }
  # endif
  static CRYPTO_ONCE engine_dynamic = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_dynamic)
  {
  # ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_dynamic: "
                      "engine_load_dynamic_int()\n");
  # endif
      engine_load_dynamic_int();
      return 1;
  }
  # ifndef OPENSSL_NO_STATIC_ENGINE
  #  if !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_HW_PADLOCK)
  static CRYPTO_ONCE engine_padlock = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_padlock)
  {
  #   ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_padlock: "
                      "engine_load_padlock_int()\n");
  #   endif
      engine_load_padlock_int();
      return 1;
  }
  #  endif
  #  if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
  static CRYPTO_ONCE engine_capi = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_capi)
  {
  #   ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_capi: "
                      "engine_load_capi_int()\n");
  #   endif
      engine_load_capi_int();
      return 1;
  }
  #  endif
  #  if !defined(OPENSSL_NO_AFALGENG)
  static CRYPTO_ONCE engine_afalg = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_afalg)
  {
  #   ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_afalg: "
                      "engine_load_afalg_int()\n");
  #   endif
      engine_load_afalg_int();
      return 1;
  }
  #  endif
  # endif
  #endif
  
  #ifndef OPENSSL_NO_COMP
  static CRYPTO_ONCE zlib = CRYPTO_ONCE_STATIC_INIT;
  
  static int zlib_inited = 0;
  DEFINE_RUN_ONCE_STATIC(ossl_init_zlib)
  {
      /* Do nothing - we need to know about this for the later cleanup */
      zlib_inited = 1;
      return 1;
  }
  #endif
  
  static void ossl_init_thread_stop(struct thread_local_inits_st *locals)
  {
      /* Can't do much about this */
      if (locals == NULL)
          return;
  
      if (locals->async) {
  #ifdef OPENSSL_INIT_DEBUG
          fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_stop: "
                          "ASYNC_cleanup_thread()\n");
  #endif
          ASYNC_cleanup_thread();
      }
  
      if (locals->err_state) {
  #ifdef OPENSSL_INIT_DEBUG
          fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_stop: "
                          "err_delete_thread_state()\n");
  #endif
          err_delete_thread_state();
      }
  
      OPENSSL_free(locals);
  }
  
  void OPENSSL_thread_stop(void)
  {
      ossl_init_thread_stop(
          (struct thread_local_inits_st *)ossl_init_get_thread_local(0));
  }
  
  int ossl_init_thread_start(uint64_t opts)
  {
      struct thread_local_inits_st *locals;
  
      if (!OPENSSL_init_crypto(0, NULL))
          return 0;
  
      locals = ossl_init_get_thread_local(1);
  
      if (locals == NULL)
          return 0;
  
      if (opts & OPENSSL_INIT_THREAD_ASYNC) {
  #ifdef OPENSSL_INIT_DEBUG
          fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_start: "
                          "marking thread for async\n");
  #endif
          locals->async = 1;
      }
  
      if (opts & OPENSSL_INIT_THREAD_ERR_STATE) {
  #ifdef OPENSSL_INIT_DEBUG
          fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_start: "
                          "marking thread for err_state\n");
  #endif
          locals->err_state = 1;
      }
  
      return 1;
  }
  
  void OPENSSL_cleanup(void)
  {
      OPENSSL_INIT_STOP *currhandler, *lasthandler;
  
      /* If we've not been inited then no need to deinit */
      if (!base_inited)
          return;
  
      /* Might be explicitly called and also by atexit */
      if (stopped)
          return;
      stopped = 1;
  
      /*
       * Thread stop may not get automatically called by the thread library for
       * the very last thread in some situations, so call it directly.
       */
      ossl_init_thread_stop(ossl_init_get_thread_local(0));
  
      currhandler = stop_handlers;
      while (currhandler != NULL) {
          currhandler->handler();
          lasthandler = currhandler;
          currhandler = currhandler->next;
          OPENSSL_free(lasthandler);
      }
      stop_handlers = NULL;
  
      CRYPTO_THREAD_lock_free(init_lock);
  
      /*
       * We assume we are single-threaded for this function, i.e. no race
       * conditions for the various "*_inited" vars below.
       */
  
  #ifndef OPENSSL_NO_COMP
      if (zlib_inited) {
  #ifdef OPENSSL_INIT_DEBUG
          fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                          "comp_zlib_cleanup_int()\n");
  #endif
          comp_zlib_cleanup_int();
      }
  #endif
  
      if (async_inited) {
  # ifdef OPENSSL_INIT_DEBUG
          fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                          "async_deinit()\n");
  # endif
          async_deinit();
      }
  
      if (load_crypto_strings_inited) {
  #ifdef OPENSSL_INIT_DEBUG
          fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                          "err_free_strings_int()\n");
  #endif
          err_free_strings_int();
      }
  
      CRYPTO_THREAD_cleanup_local(&threadstopkey);
  
  #ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "rand_cleanup_int()\n");
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "conf_modules_free_int()\n");
  #ifndef OPENSSL_NO_ENGINE
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "engine_cleanup_int()\n");
  #endif
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "crypto_cleanup_all_ex_data_int()\n");
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "bio_sock_cleanup_int()\n");
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "bio_cleanup()\n");
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "evp_cleanup_int()\n");
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "obj_cleanup_int()\n");
      fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
                      "err_cleanup()\n");
  #endif
      /*
       * Note that cleanup order is important:
       * - rand_cleanup_int could call an ENGINE's RAND cleanup function so
       * must be called before engine_cleanup_int()
       * - ENGINEs use CRYPTO_EX_DATA and therefore, must be cleaned up
       * before the ex data handlers are wiped in CRYPTO_cleanup_all_ex_data().
       * - conf_modules_free_int() can end up in ENGINE code so must be called
       * before engine_cleanup_int()
       * - ENGINEs and additional EVP algorithms might use added OIDs names so
       * obj_cleanup_int() must be called last
       */
      rand_cleanup_int();
      conf_modules_free_int();
  #ifndef OPENSSL_NO_ENGINE
      engine_cleanup_int();
  #endif
      ossl_store_cleanup_int();
      crypto_cleanup_all_ex_data_int();
      bio_cleanup();
      evp_cleanup_int();
      obj_cleanup_int();
      err_cleanup();
  
      base_inited = 0;
  }
  
  /*
   * If this function is called with a non NULL settings value then it must be
   * called prior to any threads making calls to any OpenSSL functions,
   * i.e. passing a non-null settings value is assumed to be single-threaded.
   */
  int OPENSSL_init_crypto(uint64_t opts, const OPENSSL_INIT_SETTINGS *settings)
  {
      static int stoperrset = 0;
  
      if (stopped) {
          if (!stoperrset) {
              /*
               * We only ever set this once to avoid getting into an infinite
               * loop where the error system keeps trying to init and fails so
               * sets an error etc
               */
              stoperrset = 1;
              CRYPTOerr(CRYPTO_F_OPENSSL_INIT_CRYPTO, ERR_R_INIT_FAIL);
          }
          return 0;
      }
  
      if (!base_inited && !RUN_ONCE(&base, ossl_init_base))
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_LOAD_CRYPTO_STRINGS)
              && !RUN_ONCE(&load_crypto_strings,
                           ossl_init_no_load_crypto_strings))
          return 0;
  
      if ((opts & OPENSSL_INIT_LOAD_CRYPTO_STRINGS)
              && !RUN_ONCE(&load_crypto_strings, ossl_init_load_crypto_strings))
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_ADD_ALL_CIPHERS)
              && !RUN_ONCE(&add_all_ciphers, ossl_init_no_add_algs))
          return 0;
  
      if ((opts & OPENSSL_INIT_ADD_ALL_CIPHERS)
              && !RUN_ONCE(&add_all_ciphers, ossl_init_add_all_ciphers))
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_ADD_ALL_DIGESTS)
              && !RUN_ONCE(&add_all_digests, ossl_init_no_add_algs))
          return 0;
  
      if ((opts & OPENSSL_INIT_ADD_ALL_DIGESTS)
              && !RUN_ONCE(&add_all_digests, ossl_init_add_all_digests))
          return 0;
  
      if ((opts & OPENSSL_INIT_ATFORK)
              && !openssl_init_fork_handlers())
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_LOAD_CONFIG)
              && !RUN_ONCE(&config, ossl_init_no_config))
          return 0;
  
      if (opts & OPENSSL_INIT_LOAD_CONFIG) {
          int ret;
          CRYPTO_THREAD_write_lock(init_lock);
          appname = (settings == NULL) ? NULL : settings->appname;
          ret = RUN_ONCE(&config, ossl_init_config);
          CRYPTO_THREAD_unlock(init_lock);
          if (!ret)
              return 0;
      }
  
      if ((opts & OPENSSL_INIT_ASYNC)
              && !RUN_ONCE(&async, ossl_init_async))
          return 0;
  
  #ifndef OPENSSL_NO_ENGINE
      if ((opts & OPENSSL_INIT_ENGINE_OPENSSL)
              && !RUN_ONCE(&engine_openssl, ossl_init_engine_openssl))
          return 0;
  # if !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_DEVCRYPTOENG)
      if ((opts & OPENSSL_INIT_ENGINE_CRYPTODEV)
              && !RUN_ONCE(&engine_devcrypto, ossl_init_engine_devcrypto))
          return 0;
  # endif
  # ifndef OPENSSL_NO_RDRAND
      if ((opts & OPENSSL_INIT_ENGINE_RDRAND)
              && !RUN_ONCE(&engine_rdrand, ossl_init_engine_rdrand))
          return 0;
  # endif
      if ((opts & OPENSSL_INIT_ENGINE_DYNAMIC)
              && !RUN_ONCE(&engine_dynamic, ossl_init_engine_dynamic))
          return 0;
  # ifndef OPENSSL_NO_STATIC_ENGINE
  #  if !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_HW_PADLOCK)
      if ((opts & OPENSSL_INIT_ENGINE_PADLOCK)
              && !RUN_ONCE(&engine_padlock, ossl_init_engine_padlock))
          return 0;
  #  endif
  #  if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
      if ((opts & OPENSSL_INIT_ENGINE_CAPI)
              && !RUN_ONCE(&engine_capi, ossl_init_engine_capi))
          return 0;
  #  endif
  #  if !defined(OPENSSL_NO_AFALGENG)
      if ((opts & OPENSSL_INIT_ENGINE_AFALG)
              && !RUN_ONCE(&engine_afalg, ossl_init_engine_afalg))
          return 0;
  #  endif
  # endif
      if (opts & (OPENSSL_INIT_ENGINE_ALL_BUILTIN
                  | OPENSSL_INIT_ENGINE_OPENSSL
                  | OPENSSL_INIT_ENGINE_AFALG)) {
          ENGINE_register_all_complete();
      }
  #endif
  
  #ifndef OPENSSL_NO_COMP
      if ((opts & OPENSSL_INIT_ZLIB)
              && !RUN_ONCE(&zlib, ossl_init_zlib))
          return 0;
  #endif
  
      return 1;
  }
  
  int OPENSSL_atexit(void (*handler)(void))
  {
      OPENSSL_INIT_STOP *newhand;
  
  #if !defined(OPENSSL_NO_DSO) && !defined(OPENSSL_USE_NODELETE)
      {
          union {
              void *sym;
              void (*func)(void);
          } handlersym;
  
          handlersym.func = handler;
  # ifdef DSO_WIN32
          {
              HMODULE handle = NULL;
              BOOL ret;
  
              /*
               * We don't use the DSO route for WIN32 because there is a better
               * way
               */
              ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
                                      | GET_MODULE_HANDLE_EX_FLAG_PIN,
                                      handlersym.sym, &handle);
  
              if (!ret)
                  return 0;
          }
  # else
          /*
           * Deliberately leak a reference to the handler. This will force the
           * library/code containing the handler to remain loaded until we run the
           * atexit handler. If -znodelete has been used then this is
           * unneccessary.
           */
          {
              DSO *dso = NULL;
  
              ERR_set_mark();
              dso = DSO_dsobyaddr(handlersym.sym, DSO_FLAG_NO_UNLOAD_ON_FREE);
              DSO_free(dso);
              ERR_pop_to_mark();
          }
  # endif
      }
  #endif
  
      newhand = OPENSSL_malloc(sizeof(*newhand));
      if (newhand == NULL)
          return 0;
  
      newhand->handler = handler;
      newhand->next = stop_handlers;
      stop_handlers = newhand;
  
      return 1;
  }
  
  #ifdef OPENSSL_SYS_UNIX
  /*
   * The following three functions are for OpenSSL developers.  This is
   * where we set/reset state across fork (called via pthread_atfork when
   * it exists, or manually by the application when it doesn't).
   *
   * WARNING!  If you put code in either OPENSSL_fork_parent or
   * OPENSSL_fork_child, you MUST MAKE SURE that they are async-signal-
   * safe.  See this link, for example:
   *      http://man7.org/linux/man-pages/man7/signal-safety.7.html
   */
  
  void OPENSSL_fork_prepare(void)
  {
  }
  
  void OPENSSL_fork_parent(void)
  {
  }
  
  void OPENSSL_fork_child(void)
  {
  }
  #endif
  