ref: 4da5aaebe94a8a13ceea2c001b1fd5161ef33e9b
dir: /wingui/FilePathCalc.cpp/
// FilePathCalc.cpp: implementation of the CFilePathCalc class.
// Author: Torsten Landmann
//
//////////////////////////////////////////////////////////////////////
#include "stdafx.h"
#include "FilePathCalc.h"
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
CFilePathCalc::CFilePathCalc()
{
}
CFilePathCalc::~CFilePathCalc()
{
}
bool CFilePathCalc::GetRelativePosition(const CString &oFrom, const CString &oTo, CString &oRelativePath)
{
CString oFromPath(oFrom);
CString oToPath(oTo);
oFromPath.MakeLower();
oToPath.MakeLower();
// extract raw paths
{
if (!MakePath(oFromPath) || !MakePath(oToPath))
{
return false;
}
}
// compare drive letters
{
CString oFromDrive;
CString oToDrive;
if (!ExtractDrive(oFromPath, oFromDrive) ||
!ExtractDrive(oToPath, oToDrive))
{
return false;
}
if (oFromDrive!=oToDrive)
{
// drive letters are different
oRelativePath=oTo;
return true;
}
}
// determine relative path
{
CString oUpPath;
CString oDownPath;
CString oBuf1, oBuf2;
// make paths to same depth
while (CountBackSlashes(oFromPath)>CountBackSlashes(oToPath))
{
oUpPath+="..\\";
if (!RemoveOneDirFromEnd(oFromPath, oBuf1))
{
return false;
}
}
while (CountBackSlashes(oToPath)>CountBackSlashes(oFromPath))
{
if (!RemoveOneDirFromEnd(oToPath, oBuf2))
{
return false;
}
oDownPath=oBuf2+oDownPath;
}
// keep track how deep we must go back to find
// the directory from which we can go towards
// the target directory
while (oFromPath!=oToPath)
{
oUpPath+="..\\";
if (!RemoveOneDirFromEnd(oFromPath, oBuf1))
{
return false;
}
if (!RemoveOneDirFromEnd(oToPath, oBuf2))
{
return false;
}
oDownPath=oBuf2+oDownPath;
}
CString oToFileName;
if (!ExtractFileName(oTo, oToFileName))
{
return false;
}
oRelativePath=oUpPath+oDownPath+oToFileName;
}
return true;
}
bool CFilePathCalc::ApplyRelativePath(
const CString &oRelativePath, CString &oAbsolutePath)
{
CString oRelativePathCpy(oRelativePath);
if (oRelativePathCpy.Find(':')==1)
{
// relative path contains a drive specificiation
oAbsolutePath=oRelativePath;
return true;
}
// delete ".\"s
{
while (oRelativePathCpy.Find(".\\")==0)
{
oRelativePathCpy.Delete(0, 2);
}
}
if (oRelativePathCpy.Find('\\')==0)
{
// relative path begins with a back slash
CString oDrive;
if (!ExtractDrive(oAbsolutePath, oDrive))
{
return false;
}
oAbsolutePath=oDrive+oRelativePathCpy;
return true;
}
CString oBuf1;
while (oRelativePathCpy.Find("..\\")!=-1)
{
// delete first three characters
oRelativePathCpy.Delete(0, 3);
if (!RemoveOneDirFromEnd(oAbsolutePath, oBuf1))
{
return false;
}
}
oAbsolutePath+=oRelativePathCpy;
return true;
}
bool CFilePathCalc::MakePath(CString &oStr, bool bAssumeDirectory)
{
long lCharPos, lCharPos2;
if ((lCharPos=oStr.Find(':'))!=-1)
{
// there is a colon in the string
if (oStr.Find(':', lCharPos+1)!=-1)
{
// error case: more than one colon in the string
return false;
}
if (oStr.GetAt(lCharPos+1)!='\\')
{
// the colon is not followed by a back slash
if (oStr.GetLength()>lCharPos+2)
{
// error case
// something like "c:windows" was passed on
return false;
}
else
{
// something like "c:" was passed on
oStr+="\\";
return true;
}
}
else
{
// the colon is followed by a back slash
if ((lCharPos=oStr.ReverseFind('.'))!=-1)
{
// the path description contains at least one dot
if ((lCharPos2=oStr.ReverseFind('\\'))!=-1)
{
if (lCharPos2>lCharPos || bAssumeDirectory)
{
// there is a back slash behind the last
// dot or we shall assume there is one
if (oStr.GetAt(oStr.GetLength()-1)!='\\')
{
// last character is not yet a backslash but
// it must become one
// append a back slash
oStr+='\\';
return true;
}
// path name is ok
return true;
}
else
{
// there is no back slash behind the last
// dot -> the path contains a file name;
// remove the file name;
// terminate behind last back slash
oStr.GetBuffer(0);
oStr.SetAt(lCharPos2+1, '\0');
oStr.ReleaseBuffer();
return true;
}
}
else
{
// error case: no backslash in path name
return false;
}
}
else
{
// the path description does not contain a dot
if (oStr.GetAt(oStr.GetLength()-1)!='\\')
{
// last character is not a back slash
// append a back slash
oStr+='\\';
return true;
}
else
{
// last character is a back slash
return true;
}
}
}
}
else
{
// error case: no colon in string
return false;
}
}
bool CFilePathCalc::ExtractFileName(const CString &oPath, CString &oFileName)
{
if (&oPath!=&oFileName)
{
oFileName=oPath;
}
long lBackSlashPos=oFileName.ReverseFind('\\');
if (lBackSlashPos==-1)
{
// the path did not contain a back slash
if (oFileName.Find(':')!=-1)
{
// the path contains a drive letter
// delete first two characters
oFileName.Delete(0, 2);
return true;
}
else
{
// the path did not contain a colon
return true;
}
}
else
{
// the path contains at least one backslash
// delete all characters up to the last back slash
oFileName.Delete(0, lBackSlashPos+1);
return true;
}
}
bool CFilePathCalc::ExtractDrive(const CString &oPath, CString &oDrive)
{
if (&oPath!=&oDrive)
{
oDrive=oPath;
}
if (oDrive.Find(':')==-1)
{
return false;
}
oDrive.GetBuffer(0);
oDrive.SetAt(2, '\0');
oDrive.ReleaseBuffer();
return true;
}
bool CFilePathCalc::SplitFileAndExtension(const CString &oFileName, CString &oSimpleFileName, CString &oExtension)
{
int iLastBackslashPos=oFileName.ReverseFind('\\');
int iLastDotPos=oFileName.ReverseFind('.');
int iStringLength=oFileName.GetLength();
oSimpleFileName=oFileName;
if (iLastBackslashPos>=0 && iLastDotPos>=0 && iLastBackslashPos>iLastDotPos)
{
// the last dot is BEFORE the last backslash
oExtension.Empty();
return true;
}
if (iLastDotPos==-1)
{
// there is no dot
oExtension.Empty();
return true;
}
else
{
// there is a dot
oSimpleFileName=oFileName;
oExtension=oSimpleFileName.Mid(iLastDotPos+1, iStringLength-iLastDotPos-1);
oSimpleFileName.Delete(iLastDotPos, iStringLength-iLastDotPos);
return true;
}
return false;
}
bool CFilePathCalc::IsValidFileMask(const CString &oFileMask, bool bAcceptDirectories)
{
CString oFileName;
if (!ExtractFileName(oFileMask, oFileName)) return false;
if (!bAcceptDirectories && oFileName!=oFileMask) return false; // contains a directory?
if (oFileName.IsEmpty()) return false; // "too short"
// make sure there's at least one joker
CString oFileNameTemp(oFileName);
FilterString(oFileNameTemp, "*?");
if (oFileNameTemp.IsEmpty()) return false;
CString oTemp(oFileName);
FilterStringInverse(oTemp, "/\\:\"<>|"); // these two are invalid for files but not for filters: ?*
if (oFileName!=oTemp) return false; // file path contained invalid characters
// make sure no characters are between an asterisk and the next period
int iCurPos=oFileName.Find('*');
while (iCurPos>=0 && iCurPos<oFileName.GetLength()-1)
{
if (oFileName[iCurPos+1]!='.') return false;
iCurPos=oFileName.Find('*', iCurPos+1);
}
// make sure the file doesn't end with a period
if (oFileName[oFileName.GetLength()-1]=='.') return false;
// make sure the extension doesn't contain spaces
{
CString oFileNameRaw;
CString oExtension;
if (!SplitFileAndExtension(oFileName, oFileNameRaw, oExtension)) return false;
FilterString(oExtension, " ");
if (!oExtension.IsEmpty()) return false; // extension contains spaces
}
// passed all tests
return true;
}
bool CFilePathCalc::RemoveOneDirFromEnd(CString &oPath, CString &oRemoved)
{
oRemoved=oPath;
// delete last back slash
oPath.GetBuffer(0);
oPath.SetAt(oPath.ReverseFind('\\'), '\0');
oPath.ReleaseBuffer();
long lLastBackSlashPos=
oPath.ReverseFind('\\');
if (lLastBackSlashPos==-1)
{
// error: no further back slash
return false;
}
// truncate behind last back slash
oPath.GetBuffer(0);
oPath.SetAt(lLastBackSlashPos+1, '\0');
oPath.ReleaseBuffer();
oRemoved.Delete(0, lLastBackSlashPos+1);
return true;
}
long CFilePathCalc::CountBackSlashes(const CString &oPath)
{
long lCount=0;
long lCurPos=0;
CString oDummy(oPath);
while ((lCurPos=oDummy.Find('\\', lCurPos+1))!=-1)
{
lCount++;
}
return lCount;
}
void CFilePathCalc::FilterString(CString &oString, const CString &oAcceptedChars)
{
long lCurPos=0;
while (lCurPos<oString.GetLength())
{
if (oAcceptedChars.Find(oString.GetAt(lCurPos))!=-1)
{
// character is ok
lCurPos++;
}
else
{
// character is not ok
oString.Delete(lCurPos);
}
}
}
void CFilePathCalc::FilterStringInverse(CString &oString, const CString &oCharsToRemove)
{
long lCurPos=0;
while (lCurPos<oString.GetLength())
{
if (oCharsToRemove.Find(oString.GetAt(lCurPos))==-1)
{
// character is ok
lCurPos++;
}
else
{
// character is not ok
oString.Delete(lCurPos);
}
}
}