genericopenlibs/openenvcore/backend/src/StdioRedir/Server/inidata.cpp
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Tue, 02 Feb 2010 02:01:42 +0200
changeset 0 e4d67989cc36
child 29 3520f1ef6bf6
permissions -rw-r--r--
Revision: 201002 Kit: 201005

// Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
// Name        : inidata.cpp
// Part of     : stdio server
// To read ini file
// 
//

 #include "inidata.h"
 #include <f32file.h>
 #include <e32std.h>

 // Default directory to look for INI file
 _LIT(KIniFileDir,"\\System\\Data\\");


 const TInt KTokenSize=256;

 enum TIniPanic
     {
     ESectionNameTooBig,
     EKeyNameTooBig,
     };

 
 ////////////////////////////////////////////////////////////////////////////////
 void Panic(TIniPanic aPanic)
     {
     _LIT(CIniData,"stdioserver");
     User::Panic(CIniData,aPanic);
     }



 CIniData::CIniData()
     : iPtr(NULL,0)
 /* Constructor
 */
     {
     __DECLARE_NAME(_S("CIniData"));
     }


 CIniData::~CIniData()
 /*Destructor.

  Frees the resources located in second-phase constructor

 */
     {

     delete (TText*)iPtr.Ptr();
     delete iToken;
     delete iName;
     }


 CIniData* CIniData::NewL(const TDesC& aName)
 /*
  Creates, and returns a pointer to CIniData object, leave on failure

  @return A pointer to the CiniData object
 */
     {
     CIniData* p=new(ELeave) CIniData;
     CleanupStack::PushL(p);
     p->ConstructL(aName);
     CleanupStack::Pop();
     return p;
     }


 void CIniData::ConstructL(const TDesC& aName)
 /*
  Second-phase constructor.

  The function attempts to allocate a buffer and Read file's contents into iPtr

  @param aName the name of the file which contains the ini data

  @leave One of the system-wide error codes
 */
     {
     // Allocate space for token
     iToken=HBufC::NewL(KTokenSize+2);   // 2 extra chars for [tokenName]

     // Connect to file server
     TAutoClose<RFs> fs;
     User::LeaveIfError(fs.iObj.Connect());
     fs.PushL();

	 //Add system drive to KIniFileDir with path delemiter
	 TBuf16<30> iniFilePath;
	 iniFilePath.Append(fs.iObj.GetSystemDriveChar());
	 iniFilePath.Append(TChar(KDriveDelimiter));
	 iniFilePath.Append(KIniFileDir);
     // Find file, given name
     TFindFile ff(fs.iObj);
     User::LeaveIfError(ff.FindByDir(aName, iniFilePath));
     iName=ff.File().AllocL();

     // Open file
     TAutoClose<RFile> file;
     TInt size;
     User::LeaveIfError(file.iObj.Open(fs.iObj,*iName,EFileStreamText|EFileShareReadersOrWriters));
     file.PushL();

     // Get file size and read in
     User::LeaveIfError(file.iObj.Size(size));
     TText* data=(TText*)User::AllocL(size);
     iPtr.Set(data, size/sizeof(TText), size/sizeof(TText));
     TPtr8 dest((TUint8*)data, 0, size);
     User::LeaveIfError(file.iObj.Read(dest));
     TUint8* ptr = (TUint8*)data;

     //
     // This is orderred as FEFF assuming the processor is Little Endian
     // The data in the file is FFFE.        PRR 28/9/98
     //
     if(size>=(TInt)sizeof(TText) && iPtr[0]==0xFEFF)
     {
         // UNICODE Text file so lose the FFFE
         Mem::Copy(ptr, ptr+sizeof(TText), size-sizeof(TText));
         iPtr.Set(data, size/sizeof(TText)-1, size/sizeof(TText)-1);
     }
     else if(size)
     {
         // NON-UNICODE so convert to UNICODE
         TText* newdata = (TText*)User::AllocL(size*sizeof(TText));
         iPtr.Set(newdata, size, size);
         TInt i;
         for(i=0 ; i<size ; ++i)
             iPtr[i]=ptr[i];
         delete data;
     }

     file.Pop();
     fs.Pop();
 }


 ////////////////////////////////////////////////////////////////////////////////
 //
 // Find a key's value given a section name and a key name
 //

 TBool CIniData::FindVar(const TDesC &aSectName,const TDesC &aKeyName,TPtrC &aResult)
 /* Find a text value from given aKeyName and aSecName in the ini data file

 @param aSectName Section containing key
 @param aKeyName Key being searched for in aSectName
 @param aResult On return, contains the text result

 @return ETrue if found, otherwise EFalse

 */
     {

     __ASSERT_DEBUG(aSectName.Length()<=KTokenSize,Panic(ESectionNameTooBig));
     __ASSERT_DEBUG(aKeyName.Length()<=KTokenSize,Panic(EKeyNameTooBig));

     TInt posStartOfSection(0);
     TInt posEndOfSection(iPtr.Length()); // Default to the entire length of the ini data
     TPtrC SearchBuf;

     // If we have a section, set pos to section start
     TInt posI(0);   // Position in internal data Buffer
     if( aSectName.Length() > 0 )
         {
         TBool FoundSection(false);
         while ( ! FoundSection )
             {
             // Move search buffer to next area of interest
             SearchBuf.Set(iPtr.Mid(posI));

             // Make up token "[SECTIONNAME]", to search for
             TPtr sectionToken=iToken->Des();
             _LIT(sectionTokenFmtString,"[%S]");
             sectionToken.Format(sectionTokenFmtString,&aSectName);

             // Search for next occurrence of aSectName
             TInt posSB = SearchBuf.Find(sectionToken);

             if (posSB==KErrNotFound)
                 return(EFalse);

             // Check this is at beginning of line (ie. non-commented)
             // ie. Check preceding char was LF
             if(posSB>0)
                 {
                 // Create a Buffer, starting one char before found subBuf
                 TPtrC CharBefore(SearchBuf.Right(SearchBuf.Length()-posSB+1));
                 // Check first char is end of prev
                 if(CharBefore[0] == '\n')
                     {
                     FoundSection = ETrue;       // found
                     posI = posI + posSB;
                     }
                 else
                     {
                     posI = posI + posSB + 1;    // try again
                     }
                 }
             else
                 {
                 FoundSection = ETrue;
                 }

             }   // while ( ! FoundSection )

         // Set start of section, after section name, (incl '[' and ']')
         posStartOfSection = posI + aSectName.Length() + 2;

         // Set end of section, by finding begin of next section or end
         SearchBuf.Set(iPtr.Mid(posI));
         _LIT(nextSectionBuf,"\n[");
         TInt posSB = SearchBuf.Find(nextSectionBuf);
         if(posSB != KErrNotFound)
             {
             posEndOfSection = posI + posSB;
             }
         else
             {
             posEndOfSection = iPtr.Length();
             }

         }   // if( aSectName.Length() > 0 )

     // Look for key in ini file data Buffer
     posI = posStartOfSection;
     TBool FoundKey(false);
     while ( ! FoundKey )
         {
         // Search for next occurrence of aKeyName
         SearchBuf.Set(iPtr.Mid(posI,posEndOfSection-posI));
         TInt posSB = SearchBuf.Find(aKeyName);

         // If not found, return
         if (posSB==KErrNotFound)
             return(EFalse);

         // Check this is at beginning of line (ie. non-commented)
         // ie. Check preceding char was CR or LF
         if(posSB>0)
             {
             // Create a Buffer, starting one char before found subBuf
             TPtrC CharBefore(SearchBuf.Right(SearchBuf.Length()-posSB+1));
             // Check if the first char is end of prev and also check
             // if the token found is not a substring of another string
             TBool beginningOK = ((CharBefore[0] == '\n') || (CharBefore[0] == ' ') || (CharBefore[0] == '\t'));
             TBool endingOK = ((CharBefore[aKeyName.Length()+1] == '=') || (CharBefore[aKeyName.Length()+1] == ' ') ||
(CharBefore[aKeyName.Length()+1] == '\t'));
             if (beginningOK && endingOK)
                 {
                 FoundKey = ETrue;
                 posI = posI + posSB;
                 }
             else
                 {
                 posI = posI + posSB + 1;
                 }
             }
         else
             {
             FoundKey = ETrue;
             }
         }   // while ( ! FoundKey )

// Set pos, to just after '=' sign
SearchBuf.Set(iPtr.Mid(posI));
TInt posSB = SearchBuf.Locate('=');
if(posSB==KErrNotFound)     // Illegal format, should flag this...
    return(EFalse);

// Identify start and end of data (EOL or EOF)
posI = posI + posSB + 1;    // 1 char after '='
TInt posValStart = posI;
TInt posValEnd;
SearchBuf.Set(iPtr.Mid(posI));
posSB = SearchBuf.Locate('\r');
if(posSB!=KErrNotFound)
    {
    posValEnd = posI + posSB;
    }
else
    {
    posValEnd = iPtr.Length();
    }

// Check we are still in the section requested
if( aSectName.Length() > 0 )
    {
    if( posValEnd > posEndOfSection )
        {
        return(EFalse);
        }
    }
// Parse Buffer from posn of key
// Start one space after '='
TLex lex(iPtr.Mid(posValStart, posValEnd-posValStart));
lex.SkipSpaceAndMark();     // Should be at the start of the data
aResult.Set(lex.MarkedToken().Ptr(),posValEnd-posValStart - lex.Offset() );
return(ETrue);
}

////////////////////////////////////////////////////////////////////////////////
TBool CIniData::FindVar(const TDesC &aSection,const TDesC &aKeyName,TInt &aResult)
/* Find an integer value from given aKeyName and aSecName in the ini data file

@param aSectName Section containing key
@param aKeyName Key being searched for  in aSectName
@param aResult On return, contains TInt result

@return ETrue if found, otherwise EFalse

*/
{
TPtrC ptr(NULL,0);
if (FindVar(aSection,aKeyName,ptr))
    {
    TLex lex(ptr);
    if (lex.Val(aResult)==KErrNone)
        return(ETrue);
    }
return(EFalse);
}