tpl_dynLhash.H

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/*
                          Aleph_w
 
  Data structures & Algorithms
  version 2.0.0b
  https://github.com/lrleon/Aleph-w
 
  This file is part of Aleph-w library
 
  Copyright (c) 2002-2026 Leandro Rabindranath Leon
 
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
 
  The above copyright notice and this permission notice shall be included in all
  copies or substantial portions of the Software.
 
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/
 
 
# ifndef TPL_DYNLHASH_H
# define TPL_DYNLHASH_H
 
# include <tpl_lhash.H>
# include <ah-errors.H>
 
using namespace Aleph;
 
namespace Aleph
{
  template <typename Key, typename Record, class Cmp = Aleph::equal_to<Key>>
  class DynLhashTable : public LhashTableVtl<Key>
  {
  private:
    struct DLBucket : public LhashTableVtl<Key>::Bucket
    {
      Record record;
 
      DLBucket(const Key & key, const Record & _record)
        : LhashTableVtl<Key>::Bucket(key), record(_record)
      { /* Empty */
      }
 
      DLBucket(const Key & key, Record && _record)
        : LhashTableVtl<Key>::Bucket(key), record(std::forward<Record>(_record))
      { /* Empty */
      }
 
      DLBucket(Key && key, const Record & _record)
        : LhashTableVtl<Key>::Bucket(std::forward<Key>(key)), record(_record)
      { /* Empty */
      }
 
      DLBucket(Key && key, Record && _record)
        : LhashTableVtl<Key>::Bucket(std::forward<Key>(key)),
          record(std::forward<Record>(_record))
      { /* Empty */
      }
    };
 
    static DLBucket * record_to_bucket(Record *rec)
    {
      DLBucket *ret_val = 0;
      size_t offset = (size_t) &ret_val->record;
      return (DLBucket *) (((size_t) rec) - offset);
    }
 
    class DLProxy
    {
      DynLhashTable & table;
      const Key & key;
      DLBucket *bucket;
 
    public:
      DLProxy(DynLhashTable & _table, const Key & _key)
        : table(_table), key(_key)
      {
        Record *record = table.search(key);
        bucket = record not_eq nullptr ? record_to_bucket(record) : nullptr;
      }
 
      operator const Record &() const
      {
        ah_invalid_argument_if(bucket == nullptr)
        << "access to unexisting entry";
 
        return bucket->record;
      }
 
      DLProxy &operator =(const Record & record)
      {
        if (bucket != nullptr)
          {
            bucket->record = record;
            return *this;
          }
 
        bucket = new DLBucket(key, record);
        table.LhashTableVtl<Key>::insert(bucket);
        return *this;
      }
 
      DLProxy &operator =(const DLProxy & proxy)
      {
        ah_invalid_argument_if(proxy.bucket == nullptr)
        << "access to unexisting entry";
 
        if (bucket != nullptr)
          {
            bucket->record = proxy.bucket->record;
            return *this;
          }
 
        bucket = new DLBucket(key, proxy.bucket->record);
        table.LhashTableVtl<Key>::insert(bucket);
        return *this;
      }
    };
 
  public:
    using Hash_Fct_Ptr = typename DynLhashTable<Key, Record>::Hash_Fct_Ptr;
 
    void swap(DynLhashTable & table) noexcept
    {
      this->LhashTableVtl<Key>::swap(table);
    }
 
    DynLhashTable(size_t len = DefaultPrime,
                  Hash_Fct_Ptr hash_fct = dft_hash_fct<Key>)
      : LhashTableVtl<Key>(len, hash_fct)
    {
      // Empty
    }
 
  private:
    void copy(const DynLhashTable & table)
    {
      for (typename LhashTableVtl<Key>::Iterator it(const_cast<DynLhashTable &>(table));
           it.has_curr(); it.next_ne())
        {
          auto *Bucket = static_cast<DLBucket *>(it.get_curr());
          insert(Bucket->get_key(), Bucket->record);
        }
    }
 
  public:
    DynLhashTable(const DynLhashTable & table)
      : LhashTableVtl<Key>()
    {
      copy(table);
    }
 
    DynLhashTable(DynLhashTable && table) noexcept
      : LhashTableVtl<Key>(std::move(table))
    {
      // Base class move constructor properly transfers ownership
    }
 
    DynLhashTable &operator =(const DynLhashTable & table)
    {
      if (this == &table)
        return *this;
 
      this->empty();
      copy(table);
 
      return *this;
    }
 
    DynLhashTable &operator =(DynLhashTable && table) noexcept
    {
      if (this != &table)
        LhashTableVtl<Key>::operator=(std::move(table));
      return *this;
    }
 
  private:
    Record * __insert(DLBucket *bucket)
    {
      LhashTableVtl<Key>::insert(bucket);
      return &bucket->record;
    }
 
  public:
    Record * insert(const Key & key, const Record & record)
    {
      return __insert(new DLBucket(key, record));
    }
 
    Record * insert(const Key & key, Record && record = Record())
    {
      return __insert(new DLBucket(key, std::forward<Record>(record)));
    }
 
    Record * insert(Key && key, const Record & record)
    {
      return __insert(new DLBucket(std::forward<Key>(key), record));
    }
 
    Record * insert(Key && key, Record && record)
    {
      return __insert(new DLBucket(std::forward<Key>(key),
                                   std::forward<Record>(record)));
    }
 
    Record * search(const Key & key)
    {
      auto *bucket = static_cast<DLBucket *>(LhashTableVtl<Key>::search(key));
      return bucket != nullptr ? &bucket->record : nullptr;
    }
 
    void remove(Record *record)
    {
      DLBucket *bucket = record_to_bucket(record);
      LhashTableVtl<Key>::remove(bucket);
      delete bucket;
    }
 
    DLProxy operator [](const Key & key) const
    {
      return DLProxy(const_cast<DynLhashTable &>(*this), key);
    }
 
    DLProxy operator [](const Key & key)
    {
      return DLProxy(*this, key);
    }
  };
} // end namespace Aleph
 
# endif // TPL_DYNLHASH_H