File indexing completed on 2024-05-05 05:53:47

 /*
     SPDX-FileCopyrightText: 1997, 1998 Lars Doelle <lars.doelle@on-line.de>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #ifndef HISTORYFILE_H
 #define HISTORYFILE_H
 
 // Qt
 #include <QTemporaryFile>
 
 #include "konsoleprivate_export.h"
 
 namespace Konsole
 {
 /*
    An extendable tmpfile(1) based buffer.
 */
 class HistoryFile
 {
 public:
     HistoryFile();
     virtual ~HistoryFile();
 
     virtual void add(const char *buffer, qint64 count);
     virtual void get(char *buffer, qint64 size, qint64 loc);
     virtual void set(char *buffer, qint64 size, qint64 loc);
     virtual void removeLast(qint64 loc);
     virtual qint64 len() const;
 
     // mmaps the file in read-only mode
     void map();
     // un-mmaps the file
     void unmap();
 
 private:
     qint64 _length;
     QTemporaryFile _tmpFile;
 
     // pointer to start of mmap'ed file data, or 0 if the file is not mmap'ed
     uchar *_fileMap;
 
     // incremented whenever 'add' is called and decremented whenever
     //'get' is called.
     // this is used to detect when a large number of lines are being read and processed from the history
     // and automatically mmap the file for better performance (saves the overhead of many lseek-read calls).
     int _readWriteBalance;
 
     // when _readWriteBalance goes below this threshold, the file will be mmap'ed automatically
     static const int MAP_THRESHOLD = -1000;
 };
 
 }
 
 #endif