File indexing completed on 2025-01-19 04:23:24

 /*
     This file is part of Konsole, an X terminal.
     Copyright (C) 2000 by Stephan Kulow <coolo@kde.org>
 
     Rewritten for QT4 by e_k <e_k at users.sourceforge.net>, Copyright (C)2008
 
     This program 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 2 of the License, or
     (at your option) any later version.
 
     This program 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 this program; if not, write to the Free Software
     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
     02110-1301  USA.
 */
 
 #ifndef BLOCKARRAY_H
 #define BLOCKARRAY_H
 
 #include <unistd.h>
 
 //#error Do not use in KDE 2.1
 
 #define BlockSize (1 << 12)
 #define ENTRIES   ((BlockSize - sizeof(size_t) ) / sizeof(unsigned char))
 
 namespace Konsole {
 
 struct Block {
     Block() {
         size = 0;
     }
     unsigned char data[ENTRIES];
     size_t size;
 };
 
 // ///////////////////////////////////////////////////////
 
 class BlockArray {
 public:
     /**
     * Creates a history file for holding
     * maximal size blocks. If more blocks
     * are requested, then it drops earlier
     * added ones.
     */
     BlockArray();
 
     /// destructor
     ~BlockArray();
 
     /**
     * adds the Block at the end of history.
     * This may drop other blocks.
     *
     * The ownership on the block is transfered.
     * An unique index number is returned for accessing
     * it later (if not yet dropped then)
     *
     * Note, that the block may be dropped completely
     * if history is turned off.
     */
     size_t append(Block * block);
 
     /**
     * gets the block at the index. Function may return
     * 0 if the block isn't available any more.
     *
     * The returned block is strictly readonly as only
     * maped in memory - and will be invalid on the next
     * operation on this class.
     */
     const Block * at(size_t index);
 
     /**
     * reorders blocks as needed. If newsize is null,
     * the history is emptied completely. The indices
     * returned on append won't change their semantic,
     * but they may not be valid after this call.
     */
     bool setHistorySize(size_t newsize);
 
     size_t newBlock();
 
     Block * lastBlock() const;
 
     /**
     * Convenient function to set the size in KBytes
     * instead of blocks
     */
     bool setSize(size_t newsize);
 
     size_t len() const {
         return length;
     }
 
     bool has(size_t index) const;
 
     size_t getCurrent() const {
         return current;
     }
 
 private:
     void unmap();
     void increaseBuffer();
     void decreaseBuffer(size_t newsize);
 
     size_t size;
     // current always shows to the last inserted block
     size_t current;
     size_t index;
 
     Block * lastmap;
     size_t lastmap_index;
     Block * lastblock;
 
     int ion;
     size_t length;
 
 };
 
 }
 
 #endif