--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libqterminal/unix/BlockArray.h	Mon Jan 30 11:23:13 2012 +0100
@@ -0,0 +1,118 @@
+/*
+    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>
+
+#define BlockSize (1 << 12)
+#define ENTRIES   ((BlockSize - sizeof(size_t) ) / sizeof(unsigned char))
+
+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