modules/rosapps/applications/sysutils/regexpl/TextHistory.cpp

   1 /*
   2  * regexpl - Console Registry Explorer
   3  *
   4  * Copyright (C) 2000-2005 Nedko Arnaudov <nedko@users.sourceforge.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; see the file COPYING.  If not, write to
  18  * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19  * Boston, MA 02111-1307, USA.
  20  */
  21
  22 // TextHistory.cpp: implementation of the CTextHistory class.
  23 //
  24 //////////////////////////////////////////////////////////////////////
  25
  26 #include "ph.h"
  27 #include "TextHistory.h"
  28
  29 //////////////////////////////////////////////////////////////////////
  30 // Construction/Destruction
  31 //////////////////////////////////////////////////////////////////////
  32
  33 CTextHistory::CTextHistory()
  34 {
  35         m_pHistoryBuffer = NULL;
  36         m_dwMaxHistoryLines = 0;
  37 }
  38
  39 CTextHistory::~CTextHistory()
  40 {
  41         if (m_pHistoryBuffer) delete[] m_pHistoryBuffer;
  42 }
  43
  44 BOOL CTextHistory::Init(DWORD dwMaxHistoryLineSize, DWORD dwMaxHistoryLines)
  45 {
  46         if (!dwMaxHistoryLines)
  47         {
  48                 ASSERT(FALSE);
  49                 return FALSE;
  50         }
  51         if (m_pHistoryBuffer) delete[] m_pHistoryBuffer;
  52         m_dwFirstHistoryIndex = 0;
  53         m_dwLastHistoryIndex = 0;
  54         m_dwHisoryFull = 0;
  55         m_dwMaxHistoryLines = dwMaxHistoryLines;
  56         m_dwMaxHistoryLineSize = dwMaxHistoryLineSize;
  57         m_pHistoryBuffer = new (std::nothrow) TCHAR [m_dwMaxHistoryLines*dwMaxHistoryLineSize];
  58         if (!m_pHistoryBuffer) return FALSE;
  59         return TRUE;
  60 }
  61
  62 void CTextHistory::AddHistoryLine(const TCHAR *pchLine)
  63 {
  64         if (!m_pHistoryBuffer) return;
  65         if (_tcslen(pchLine) == 0) return;
  66         if (_tcslen(pchLine) >= m_dwMaxHistoryLineSize)
  67         {
  68                 ASSERT(FALSE);
  69                 return;
  70         }
  71         if (m_dwHisoryFull == m_dwMaxHistoryLines)      // if buffer is full, replace last
  72         {
  73                 ASSERT(m_dwFirstHistoryIndex == m_dwLastHistoryIndex);
  74                 m_dwLastHistoryIndex = (m_dwLastHistoryIndex+1)%m_dwMaxHistoryLines;
  75         }
  76         ASSERT(m_dwFirstHistoryIndex < m_dwMaxHistoryLines);
  77         _tcscpy(m_pHistoryBuffer+m_dwFirstHistoryIndex*m_dwMaxHistoryLineSize,pchLine);
  78         m_dwFirstHistoryIndex = (m_dwFirstHistoryIndex+1)%m_dwMaxHistoryLines;
  79         ASSERT(m_dwHisoryFull <= m_dwMaxHistoryLines);
  80         if (m_dwHisoryFull < m_dwMaxHistoryLines) m_dwHisoryFull++;
  81 }
  82
  83 const TCHAR * CTextHistory::GetHistoryLine(DWORD dwIndex)
  84 {
  85         if (!m_pHistoryBuffer) return NULL;
  86         ASSERT(m_dwHisoryFull <= m_dwMaxHistoryLines);
  87         if (dwIndex >= m_dwHisoryFull) return NULL;
  88         dwIndex = m_dwHisoryFull - dwIndex - 1;
  89         dwIndex = (dwIndex+m_dwLastHistoryIndex) % m_dwMaxHistoryLines;
  90         ASSERT(dwIndex < m_dwMaxHistoryLines);
  91         return m_pHistoryBuffer+dwIndex*m_dwMaxHistoryLineSize;
  92 }