src/apps/terminal/HistoryBuffer.h

   1 /*
   2  * Copyright 2008, Ingo Weinhold, ingo_weinhold@gmx.de.
   3  * Distributed under the terms of the MIT License.
   4  */
   5 #ifndef HISTORY_BUFFER_H
   6 #define HISTORY_BUFFER_H
   7
   8 #include <SupportDefs.h>
   9
  10 #include "TerminalLine.h"
  11
  12
  13 struct HistoryLine;
  14 struct TerminalLine;
  15
  16
  17 class HistoryBuffer {
  18 public:
  19                                                                 HistoryBuffer();
  20                                                                 ~HistoryBuffer();
  21
  22                         status_t                        Init(int32 width, int32 capacity);
  23
  24                         void                            Clear();
  25
  26                         int32                           Width() const           { return fWidth; }
  27                         int32                           Capacity() const        { return fCapacity; }
  28                         int32                           Size() const            { return fSize; }
  29
  30         inline  HistoryLine*            LineAt(int32 index) const;
  31                         TerminalLine*           GetTerminalLineAt(int32 index,
  32                                                                         TerminalLine* buffer) const;
  33
  34                         void                            AddLine(const TerminalLine* line);
  35                         void                            AddEmptyLines(int32 count);
  36                         void                            DropLines(int32 count);
  37
  38 private:
  39                         HistoryLine*            _AllocateLine(int32 attributesRuns,
  40                                                                         int32 byteLength);
  41         inline  HistoryLine*            _LineAt(int32 index) const;
  42
  43 private:
  44                         HistoryLine*            fLines;
  45                         int32                           fWidth;
  46                         int32                           fCapacity;
  47                         int32                           fNextLine;
  48                         int32                           fSize;
  49                         uint8*                          fBuffer;
  50                         int32                           fBufferSize;
  51                         int32                           fBufferAllocationOffset;
  52 };
  53
  54
  55 inline HistoryLine*
  56 HistoryBuffer::_LineAt(int32 index) const
  57 {
  58         return &fLines[(fCapacity + fNextLine - index - 1) % fCapacity];
  59 }
  60
  61
  62 inline HistoryLine*
  63 HistoryBuffer::LineAt(int32 index) const
  64 {
  65         return index >= 0 && index < fSize ? _LineAt(index) : NULL;
  66 }
  67
  68
  69 #endif  // HISTORY_BUFFER_H