Move hashmap function comments to the header file

typedef void (*key_free_fn)(void *data);

typedef void (*data_free_fn)(void *data);

// Lifecycle.

// Returns a new, empty hash_map. Returns NULL if not enough memory could be allocated

// for the hash_map structure. The returned hash_map must be freed with |hash_map_free|.

// The |num_bucket| specifies the number of hashable buckets for the map and must not

// be zero.  The |hash_fn| specifies a hash function to be used and must not be NULL.

// The |key_fn| and |data_fn| are called whenever a hash_map element is removed from

// the hash_map. They can be used to release resources held by the hash_map element,

// e.g.  memory or file descriptor.  |key_fn| and |data_fn| may be NULL if no cleanup

// is necessary on element removal. |equality_fn| is used to check for key equality.

// If |equality_fn| is NULL, default pointer equality is used.

hash_map_t *hash_map_new(

    size_t size,

    hash_index_fn hash_fn,

    data_free_fn data_fn,

    key_equality_fn equality_fn);

// Frees the hash_map. This function accepts NULL as an argument, in which case it

// behaves like a no-op.

void hash_map_free(hash_map_t *hash_map);

// Accessors.

void *hash_map_get(const hash_map_t *hash_map, const void *key);

bool hash_map_has_key(const hash_map_t *hash_map, const void *key);

// Returns true if the hash_map is empty (has no elements), false otherwise.

// Note that a NULL |hash_map| is not the same as an empty |hash_map|. This function

// does not accept a NULL |hash_map|.

bool hash_map_is_empty(const hash_map_t *hash_map);

// Returns the number of elements in the hash map.  This function does not accept a

// NULL |hash_map|.

size_t hash_map_size(const hash_map_t *hash_map);

// Returns the number of buckets in the hash map.  This function does not accept a

// NULL |hash_map|.

size_t hash_map_num_buckets(const hash_map_t *hash_map);

// Mutators.

// Returns true if the hash_map has a valid entry for the presented key.

// This function does not accept a NULL |hash_map|.

bool hash_map_has_key(const hash_map_t *hash_map, const void *key);

// Returns the element indexed by |key| in the hash_map without removing it. |hash_map|

// may not be NULL.  Returns NULL if no entry indexed by |key|.

void *hash_map_get(const hash_map_t *hash_map, const void *key);

// Sets the value |data| indexed by |key| into the |hash_map|. Neither |data| nor

// |hash_map| may be NULL.  This function does not make copies of |data| nor |key|

// so the pointers must remain valid at least until the element is removed from the

// hash_map or the hash_map is freed.  Returns true if |data| could be set, false

// otherwise (e.g. out of memory).

bool hash_map_set(hash_map_t *hash_map, const void *key, void *data);

// Removes data indexed by |key| from the hash_map. |hash_map| may not be NULL.

// If |key_fn| or |data_fn| functions were specified in |hash_map_new|, they

// will be called back with |key| or |data| respectively. This function returns true

// if |key| was found in the hash_map and removed, false otherwise.

bool hash_map_erase(hash_map_t *hash_map, const void *key);

// Removes all elements in the hash_map. Calling this function will return the hash_map

// to the same state it was in after |hash_map_new|. |hash_map| may not be NULL.

void hash_map_clear(hash_map_t *hash_map);

// Iteration.

// Iterates through the entire |hash_map| and calls |callback| for each data

// element and passes through the |context| argument. If the hash_map is

// empty, |callback| will never be called. It is not safe to mutate the

// hash_map inside the callback. Neither |hash_map| nor |callback| may be NULL.

// If |callback| returns false, the iteration loop will immediately exit.

void hash_map_foreach(hash_map_t *hash_map, hash_map_iter_cb callback, void *context);

  return hash_map;

}

// Returns a new, empty hash_map. Returns NULL if not enough memory could be allocated

// for the hash_map structure. The returned hash_map must be freed with |hash_map_free|.

// The |num_bucket| specifies the number of hashable buckets for the map and must not

// be zero.  The |hash_fn| specifies a hash function to be used and must not be NULL.

// The |key_fn| and |data_fn| are called whenever a hash_map element is removed from

// the hash_map. They can be used to release resources held by the hash_map element,

// e.g.  memory or file descriptor.  |key_fn| and |data_fn| may be NULL if no cleanup

// is necessary on element removal. |equality_fn| is used to check for key equality.

// If |equality_fn| is NULL, default pointer equality is used.

hash_map_t *hash_map_new(

    size_t num_bucket,

    hash_index_fn hash_fn,

  return hash_map_new_internal(num_bucket, hash_fn, key_fn, data_fn, equality_fn, &allocator_calloc);

}

// Frees the hash_map. This function accepts NULL as an argument, in which case it

// behaves like a no-op.

void hash_map_free(hash_map_t *hash_map) {

  if (hash_map == NULL)

    return;

  hash_map->allocator->free(hash_map);

}

// Returns true if the hash_map is empty (has no elements), false otherwise.

// Note that a NULL |hash_map| is not the same as an empty |hash_map|. This function

// does not accept a NULL |hash_map|.

bool hash_map_is_empty(const hash_map_t *hash_map) {

  assert(hash_map != NULL);

  return (hash_map->hash_size == 0);

}

// Returns the number of elements in the hash map.  This function does not accept a

// NULL |hash_map|.

size_t hash_map_size(const hash_map_t *hash_map) {

  assert(hash_map != NULL);

  return hash_map->hash_size;

}

// Returns the number of buckets in the hash map.  This function does not accept a

// NULL |hash_map|.

size_t hash_map_num_buckets(const hash_map_t *hash_map) {

  assert(hash_map != NULL);

  return hash_map->num_bucket;

}

// Returns true if the hash_map has a valid entry for the presented key.

// This function does not accept a NULL |hash_map|.

bool hash_map_has_key(const hash_map_t *hash_map, const void *key) {

  assert(hash_map != NULL);

  return (hash_map_entry != NULL);

}

// Sets the value |data| indexed by |key| into the |hash_map|. Neither |data| nor

// |hash_map| may be NULL.  This function does not make copies of |data| nor |key|

// so the pointers must remain valid at least until the element is removed from the

// hash_map or the hash_map is freed.  Returns true if |data| could be set, false

// otherwise (e.g. out of memory).

bool hash_map_set(hash_map_t *hash_map, const void *key, void *data) {

  assert(hash_map != NULL);

  assert(data != NULL);

  return list_append(hash_bucket_list, hash_map_entry);

}

// Removes data indexed by |key| from the hash_map. |hash_map| may not be NULL.

// If |key_fn| or |data_fn| functions were specified in |hash_map_new|, they

// will be called back with |key| or |data| respectively. This function returns true

// if |key| was found in the hash_map and removed, false otherwise.

bool hash_map_erase(hash_map_t *hash_map, const void *key) {

  assert(hash_map != NULL);

  return list_remove(hash_bucket_list, hash_map_entry);

}

// Returns the element indexed by |key| in the hash_map without removing it. |hash_map|

// may not be NULL.  Returns NULL if no entry indexed by |key|.

void *hash_map_get(const hash_map_t *hash_map, const void *key) {

  assert(hash_map != NULL);

  return NULL;

}

// Removes all elements in the hash_map. Calling this function will return the hash_map

// to the same state it was in after |hash_map_new|. |hash_map| may not be NULL.

void hash_map_clear(hash_map_t *hash_map) {

  assert(hash_map != NULL);

  }

}

// Iterates through the entire |hash_map| and calls |callback| for each data

// element and passes through the |context| argument. If the hash_map is

// empty, |callback| will never be called. It is not safe to mutate the

// hash_map inside the callback. Neither |hash_map| nor |callback| may be NULL.

// If |callback| returns false, the iteration loop will immediately exit.

void hash_map_foreach(hash_map_t *hash_map, hash_map_iter_cb callback, void *context) {

  assert(hash_map != NULL);

  assert(callback != NULL);