os/kernelhwsrv/kerneltest/f32test/locl/CodepageUtils/src/t_cputils_unicodeconv.cpp
author sl@SLION-WIN7.fritz.box
Fri, 15 Jun 2012 03:10:57 +0200
changeset 0 bde4ae8d615e
permissions -rw-r--r--
First public contribution.
     1 // Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
     2 // All rights reserved.
     3 // This component and the accompanying materials are made available
     4 // under the terms of the License "Eclipse Public License v1.0"
     5 // which accompanies this distribution, and is available
     6 // at the URL "http://www.eclipse.org/legal/epl-v10.html".
     7 //
     8 // Initial Contributors:
     9 // Nokia Corporation - initial contribution.
    10 //
    11 // Contributors:
    12 //
    13 // Description:
    14 //
    15 
    16 #include <e32std.h>
    17 #include <e32def.h>
    18 #include <e32des8.h> 
    19 #include "t_cputils_unicodeconv.h"
    20 
    21 //replacement character to be used when unicode cannot be converted
    22 const TUint8 KForeignReplacement = 0x5F;
    23 
    24 //This function converts from Unicoded characters, to foreign characters and adds them into a descriptor
    25 EXPORT_C void UnicodeConv::ConvertFromUnicodeL(TDes8& aForeign, const TDesC16& aUnicode)
    26     {
    27     UnicodeConv::ConvertFromUnicodeL(aForeign, aUnicode, ETrue);
    28     }
    29 
    30 //This function converts from Unicoded characters, to foreign characters and adds them into a descriptor
    31 EXPORT_C TInt UnicodeConv::ConvertFromUnicodeL(TDes8& aForeign, const TDesC16& aUnicode, TBool leaveWhenOverflow)
    32 	{
    33 	const TInt unicodeLength = aUnicode.Length();
    34 	
    35 	//loop going through the character of the unicode descriptor
    36 	for(TInt i=0; i<unicodeLength; i++)
    37 		{
    38 		const TUint16 unicodeChar = aUnicode[i];
    39 		
    40 		// if the output buffer is already full, leave with KErrOverflow
    41 		if ( aForeign.Length() >= aForeign.MaxLength() )
    42 		    {
    43 		    if (leaveWhenOverflow)
    44 		        User::Leave(KErrOverflow);
    45 		    else
    46 		        return KErrOverflow;
    47 		    }			
    48 
    49 		//charcters from 0x0000 to 0x007F, can be mapped directly
    50 		if(unicodeChar<0x0080)
    51 			{
    52 			aForeign.Append(static_cast<TUint8>(unicodeChar));
    53 			}
    54 		else
    55 			{
    56 			TInt trailByte = KErrNotFound;
    57 			TInt returnValue = TConvDataStruct::ConvertSingleUnicode(unicodeChar,trailByte);
    58 			
    59 			if(returnValue!=KErrNotFound)
    60 				{
    61 				if(trailByte!=KErrNotFound)		
    62 					{					
    63 					// as two bytes are being added check enough space for second
    64 					if ( aForeign.Length() + 2 <= aForeign.MaxLength() )
    65 					    {
    66 					    aForeign.Append(static_cast<TUint8>(returnValue));
    67 					    aForeign.Append(static_cast<TUint8>(trailByte));
    68 					    }
    69 					else
    70 					    {
    71 			            if (leaveWhenOverflow)
    72 			                User::Leave(KErrOverflow);
    73 			            else
    74 			                return KErrOverflow;
    75 					    }					
    76 					}
    77 				else
    78 					aForeign.Append(static_cast<TUint8>(returnValue));
    79 				}		
    80 			else
    81 				aForeign.Append(KForeignReplacement);
    82 			}
    83 		}
    84 
    85 	return KErrNone;
    86 	}
    87 				
    88 //This function converts from foreign characters into unicode and adds them into a descriptor
    89 EXPORT_C void UnicodeConv::ConvertToUnicodeL(TDes16& aUnicode, const TDesC8& aForeign)
    90     {
    91     UnicodeConv::ConvertToUnicodeL(aUnicode, aForeign, ETrue);
    92     }
    93 
    94 //This function converts from foreign characters into unicode and adds them into a descriptor
    95 EXPORT_C TInt UnicodeConv::ConvertToUnicodeL(TDes16& aUnicode, const TDesC8& aForeign, TBool leaveWhenOverflow)
    96 	{
    97 	const TInt foreignLength = aForeign.Length();
    98 
    99 	//loop going through the characters of the foreign descriptor
   100 	for(TInt i = 0; i<foreignLength; i++)
   101 		{
   102 		const TUint8 leadForeign = aForeign[i];
   103 		TUint8 tailForeign = 0x00;
   104 
   105 		// Check there is enough space in the output buffer, and leave with KErrOverflow if not
   106 		if ( aUnicode.Length() == aUnicode.MaxLength() )
   107             {
   108             if (leaveWhenOverflow)
   109                 User::Leave(KErrOverflow);
   110             else
   111                 return KErrOverflow;
   112             }
   113 
   114 		//charcters from 0x00 to 0x7F, can be mapped directly
   115 		if(leadForeign < 0x80)
   116 			aUnicode.Append(static_cast<TUint16>(leadForeign));
   117 		else
   118 			{
   119 			if((i+1)<foreignLength)
   120 				tailForeign = aForeign[i+1];
   121 
   122 			const TLeadOrSingle* structPtr = TConvDataStruct::KFirstByteConversions + (leadForeign-0x80);
   123 			
   124 			if(structPtr->iUnicodeIfSingle)
   125 				aUnicode.Append(structPtr->iUnicodeIfSingle);
   126 			else
   127 				{
   128 				if(TConvDataStruct::KMinTrailByte<=tailForeign && tailForeign<=TConvDataStruct::KMaxTrailByte)
   129 					aUnicode.Append(TConvDataStruct::KDoubleByteConversions[structPtr->iDoubleByteIndex+
   130 						(tailForeign - TConvDataStruct::KMinTrailByte)]);
   131 				else
   132 					aUnicode.Append(0xFFFD);
   133 				i++;
   134 				}
   135 			}
   136 		}
   137 
   138 	return KErrNone;
   139 	}
   140 
   141 EXPORT_C TBool UnicodeConv::IsLegalShortNameCharacter (TUint aCharacter)
   142 	{
   143 	//1. aCharacter >= 0x0080 
   144 	if (aCharacter>=0x0080)
   145 		{
   146 		if (aCharacter>0xFFFF)
   147 			return EFalse;
   148 		
   149 		TInt trailByte = KErrNotFound;
   150 		TInt returnValue = TConvDataStruct::ConvertSingleUnicode(aCharacter,trailByte);
   151 		
   152 		if(returnValue!=KErrNotFound)
   153 			return ETrue;
   154 		else
   155 			return EFalse;
   156 		}
   157 	
   158     // For most common cases: 
   159     // Note: lower case characters are considered legal DOS char here. 
   160 	if ((aCharacter>='a' && aCharacter<='z') || 
   161 	    (aCharacter>='A' && aCharacter<='Z') || 
   162 	    (aCharacter>='0' && aCharacter<='9'))
   163 			{
   164 			return ETrue;
   165 			}
   166     // Checking for illegal chars: 
   167     // 2. aCharacter <= 0x20 
   168     // Note: leading 0x05 byte should be guarded by callers of this function 
   169     //  as the information of the position of the character is required. 
   170 	if (aCharacter < 0x20)
   171 		return EFalse;
   172 	// Space (' ') is not considered as a legal DOS char here.
   173 	if (aCharacter == 0x20)
   174 		return EFalse;
   175 	
   176 	// 3. 0x20 < aCharacter < 0x80 
   177     // According to FAT Spec, "following characters are not legal in any bytes of DIR_Name": 
   178     switch (aCharacter) 
   179             { 
   180             case 0x22:        // '"' 
   181             case 0x2A:        // '*' 
   182             case 0x2B:        // '+' 
   183             case 0x2C:        // ',' 
   184             //case 0x2E:        // '.'   // Although '.' is not allowed in any bytes of DIR_Name, it 
   185                                          // is a valid character in short file names. 
   186             case 0x2F:        // '/' 
   187             case 0x3A:        // ':' 
   188             case 0x3B:        // ';' 
   189             case 0x3C:        // '<' 
   190             case 0x3D:        // '=' 
   191             case 0x3E:        // '>' 
   192             case 0x3F:        // '?' 
   193             case 0x5B:        // '[' 
   194             case 0x5C:        // '\' 
   195             case 0x5D:        // ']' 
   196             case 0x7C:        // '|' 
   197             	return EFalse; 
   198             default: 
   199             	return ETrue; 
   200             } 
   201 	}		
   202