/*

  * Copyright (C) 2012 David Anderson

  *

  * This file is part of JITCraft.

  *

  * JITCraft is free software: you can redistribute it and/or modify it under

  * the terms of the GNU General Public License as published by the Free

  * Software Foundation, either version 3 of the License, or (at your option)

  * any later version.

  * 

  * Foobar is distributed in the hope that it will be useful, but WITHOUT ANY

  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS

  * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

  *

  * You should have received a copy of the GNU General Public License along with

  * JITCraft. If not, see http://www.gnu.org/licenses/.

  */

 #ifndef _include_jitcraft_string_pool_h_

 #define _include_jitcraft_string_pool_h_

 #include "AllocatorPolicies.h"

 #include "HashTable.h"

 #include "Strings.h"

 namespace ke {

 class Zone;

 class String;

 // Guarantee that strings with the same contents will map to one pointer. 

 class StringPool

 {

     class CharsAndLength {

         const char *str_;

         size_t length_;

       public:

         CharsAndLength(const char *str, size_t length)

           : str_(str),

             length_(length)

         {

         }

         const char *str() const {

             return str_;

         }

         size_t length() const {

             return length_;

         }

     };

     struct Policy

     {

         typedef String * Payload;

         static uint32 hash(const CharsAndLength &key) {

             return HashCharSequence(key.str(), key.length());

         }

         static bool matches(const CharsAndLength &key, String *string) {

             if (string->length() != key.length())

                 return false;

             return memcmp(string->chars(), key.str(), key.length() * sizeof(char)) == 0;

         }

     };

     typedef HashTable<Policy, ZoneAllocatorPolicy> StringSet;

   public:

     StringPool(Zone *zone);

     ~StringPool();

     bool initialize();

   public:

     String *add(const char *str, size_t len);

     void sweep();

   private:

     Zone *zone_;

     StringSet set_;

 };

 }

 #endif // _include_jitcraft_string_pool_h_