text: #ifndef HEADER_CURL_HASH_H
  #define HEADER_CURL_HASH_H
  /***************************************************************************
   *                                  _   _ ____  _
   *  Project                     ___| | | |  _ \| |
   *                             / __| | | | |_) | |
   *                            | (__| |_| |  _ <| |___
   *                             \___|\___/|_| \_\_____|
   *
   * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
   *
   * This software is licensed as described in the file COPYING, which
   * you should have received as part of this distribution. The terms
   * are also available at https://curl.se/docs/copyright.html.
   *
   * You may opt to use, copy, modify, merge, publish, distribute and/or sell
   * copies of the Software, and permit persons to whom the Software is
   * furnished to do so, under the terms of the COPYING file.
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
   * KIND, either express or implied.
   *
   ***************************************************************************/
  
  #include "curl_setup.h"
  
  #include <stddef.h>
  
  #include "llist.h"
  
  /* Hash function prototype */
  typedef size_t (*hash_function) (void *key,
                                   size_t key_length,
                                   size_t slots_num);
  
  /*
     Comparator function prototype. Compares two keys.
  */
  typedef size_t (*comp_function) (void *key1,
                                   size_t key1_len,
                                   void *key2,
                                   size_t key2_len);
  
  typedef void (*Curl_hash_dtor)(void *);
  
  struct Curl_hash {
    struct Curl_llist *table;
  
    /* Hash function to be used for this hash table */
    hash_function hash_func;
  
    /* Comparator function to compare keys */
    comp_function comp_func;
    Curl_hash_dtor   dtor;
    int slots;
    size_t size;
  };
  
  struct Curl_hash_element {
    struct Curl_llist_element list;
    void   *ptr;
    size_t key_len;
    char   key[1]; /* allocated memory following the struct */
  };
  
  struct Curl_hash_iterator {
    struct Curl_hash *hash;
    int slot_index;
    struct Curl_llist_element *current_element;
  };
  
  int Curl_hash_init(struct Curl_hash *h,
                     int slots,
                     hash_function hfunc,
                     comp_function comparator,
                     Curl_hash_dtor dtor);
  
  void *Curl_hash_add(struct Curl_hash *h, void *key, size_t key_len, void *p);
  int Curl_hash_delete(struct Curl_hash *h, void *key, size_t key_len);
  void *Curl_hash_pick(struct Curl_hash *, void *key, size_t key_len);
  void Curl_hash_apply(struct Curl_hash *h, void *user,
                       void (*cb)(void *user, void *ptr));
  #define Curl_hash_count(h) ((h)->size)
  void Curl_hash_destroy(struct Curl_hash *h);
  void Curl_hash_clean(struct Curl_hash *h);
  void Curl_hash_clean_with_criterium(struct Curl_hash *h, void *user,
                                      int (*comp)(void *, void *));
  size_t Curl_hash_str(void *key, size_t key_length, size_t slots_num);
  size_t Curl_str_key_compare(void *k1, size_t key1_len, void *k2,
                              size_t key2_len);
  void Curl_hash_start_iterate(struct Curl_hash *hash,
                               struct Curl_hash_iterator *iter);
  struct Curl_hash_element *
  Curl_hash_next_element(struct Curl_hash_iterator *iter);
  
  void Curl_hash_print(struct Curl_hash *h,
                       void (*func)(void *));
  
  
  #endif /* HEADER_CURL_HASH_H */
  