sl@0: // Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: // Abstraction for "an environment" holding pairs of C strings (name, value)
sl@0: // 
sl@0: //
sl@0: 
sl@0: #include "ENVIRON.H"
sl@0: #include "LPOSIX.H"
sl@0: #include <string.h>
sl@0: 
sl@0: TPtrC16 TEnvVar::ValuePtr(const wchar_t* aValue)
sl@0: //
sl@0: // Turn a zero-terminated string into a descriptor which contains the terminator
sl@0: //
sl@0: 	{
sl@0: 	TText16* value = (TText16*)aValue;
sl@0: 	return TPtrC16(value, User::StringLength(value)+1);
sl@0: 	}
sl@0: 
sl@0: void TEnvVar::ConstructL(const TDesC16& aName, const wchar_t* aValue)
sl@0: 	{
sl@0: 	TPtrC16 valueZ = ValuePtr(aValue);
sl@0: 	HBufC16* valueCopy = valueZ.AllocLC();
sl@0: 	iName = aName.AllocL();
sl@0: 	iValue = valueCopy;
sl@0: 	CleanupStack::Pop();
sl@0: 	}
sl@0: 
sl@0: void TEnvVar::Release()
sl@0: 	{
sl@0: 	delete iName;
sl@0: 	iName=0;
sl@0: 	delete iValue;
sl@0: 	iValue=0;
sl@0: 	}
sl@0: 
sl@0: TInt TEnvVar::SetValue(const wchar_t* aValue)
sl@0: //
sl@0: // Change the value - if this returns an error then the original value is still intact
sl@0: //
sl@0: 	{
sl@0: 	TPtrC16 valueZ = ValuePtr(aValue);
sl@0: 	HBufC16* valueCopy=valueZ.Alloc();
sl@0: 	if (valueCopy==0)
sl@0: 		return KErrNoMemory;
sl@0: 	delete iValue;
sl@0: 	iValue = valueCopy;
sl@0: 	return KErrNone;
sl@0: 	}
sl@0: 
sl@0: 
sl@0: HBufC16* TEnvVar::Match(const TDesC16& aName)
sl@0: //
sl@0: // return value if the name matches
sl@0: //
sl@0: 	{
sl@0: 	if (iName!=0 && iName->Compare(aName)==0)
sl@0: 		return iValue;
sl@0: 	return 0;
sl@0: 	}
sl@0: 
sl@0: TUint TEnvVar::Length() const
sl@0: //
sl@0: // How much space do we need to externalize this pair?
sl@0: // The format is name followed by '\0' followed by value followed by '\0'
sl@0: //
sl@0: 	{
sl@0: 	if (iName==0) 
sl@0: 		return 0;
sl@0: 	return iName->Length()+iValue->Length()+2;
sl@0: 	}
sl@0: 
sl@0: TInt TEnvVar::Externalize(const wchar_t* aPair, TDes16& aBuffer)
sl@0: //
sl@0: // static function to externalize a "name=value" definition
sl@0: //
sl@0: 	{
sl@0: 	const wchar_t* cp=aPair;
sl@0: 	for (cp=aPair; *cp; ++cp)
sl@0: 		{
sl@0: 		if (*cp==L'=')
sl@0: 			break;
sl@0: 		}
sl@0: 	if (*cp!=L'=')
sl@0: 		return 0;	// malformed
sl@0: 
sl@0: 	TPtrC16 name((TText16*)aPair,cp-aPair);
sl@0: 	TPtrC16 value((TText16*)(cp+1));
sl@0: 	aBuffer.Append(name);
sl@0: 	aBuffer.Append(TChar(0));
sl@0: 	aBuffer.Append(value);
sl@0: 	aBuffer.Append(TChar(0));
sl@0: 	return 1;
sl@0: 	}
sl@0: 
sl@0: TInt TEnvVar::Externalize(TDes16& aBuffer)
sl@0: 	{
sl@0: 	if (iName==0) 
sl@0: 		return 0;
sl@0: 	aBuffer.Append(*iName);
sl@0: 	aBuffer.Append(TChar(0));
sl@0: 	aBuffer.Append(*iValue);
sl@0: 	aBuffer.Append(TChar(0));
sl@0: 	return 1;
sl@0: 	}
sl@0: 
sl@0: void TEnvVar::ConstructL(const TText16*& aPtr)
sl@0: 	{
sl@0: 	TPtrC16 name(aPtr);
sl@0: 	aPtr+=name.Length()+1;
sl@0: 	ConstructL(name,(const wchar_t*)aPtr);
sl@0: 	aPtr+=iValue->Length()+1;
sl@0: 	}
sl@0: 
sl@0: CEnvironment::~CEnvironment()
sl@0: 	{
sl@0: 	while (iCount>0)
sl@0: 		{
sl@0: 		--iCount;
sl@0: 		iVars[iCount].Release();
sl@0: 		}
sl@0: 	User::Free(iVars);
sl@0: 	}
sl@0: 
sl@0: 
sl@0: void CEnvironment::ConstructL(TUint aCount, TDes16& aBuffer)
sl@0: //
sl@0: // Set up the environment from a descriptor. If this leaves then
sl@0: // the CEnvironment destructor will be able to clean up properly.
sl@0: //
sl@0: 	{
sl@0: 	// always allocate at least one slot - makes life easier elsewhere
sl@0: 	TInt bytes = (aCount+1)*sizeof(TEnvVar);
sl@0: 	iVars=(TEnvVar*) User::AllocL(bytes);
sl@0: 	Mem::FillZ(iVars,bytes);
sl@0: 	iCount=aCount+1;
sl@0: 
sl@0: 	const TText16* data=aBuffer.Ptr();
sl@0: 	for (TUint i=0; i<aCount; ++i)
sl@0: 		iVars[i].ConstructL(data);
sl@0: 	}
sl@0: 
sl@0: HBufC16* CEnvironment::ExternalizeLC(TUint& aCount, wchar_t** envp)
sl@0: 	{
sl@0: 	if (envp==0)
sl@0: 		return ExternalizeLC(aCount);	// get current environment
sl@0: 	// Externalize supplied environment
sl@0: 	TInt length=0;
sl@0: 	wchar_t** ep=envp;
sl@0: 	for (ep=envp; *ep; ++ep)
sl@0: 		length+=wcslen(*ep)+1;
sl@0: 	HBufC16* retBuf = HBufC16::NewLC(length);
sl@0: 	TInt nvars=0;
sl@0: 	TPtr16 hbuf16=retBuf->Des();
sl@0: 	for (ep=envp; *ep; ++ep)
sl@0: 		nvars+=TEnvVar::Externalize(*ep, hbuf16);
sl@0: 	aCount=nvars;
sl@0: 	return retBuf;
sl@0: 	}
sl@0: 
sl@0: HBufC16* CEnvironment::ExternalizeLC(TUint& aCount)
sl@0: 	{
sl@0: 	TInt length=0;
sl@0: 	TUint i=0;
sl@0: 	for (i=0; i<iCount; ++i)
sl@0: 		length+=iVars[i].Length();
sl@0: 	HBufC16* retBuf = HBufC16::NewLC(length);
sl@0: 	TInt nvars=0;
sl@0: 	TPtr16 hbuf16=retBuf->Des();
sl@0: 	for (i=0; i<iCount; i++)
sl@0: 		nvars+=iVars[i].Externalize(hbuf16);
sl@0: 	aCount=nvars;
sl@0: 	return retBuf;
sl@0: 	}
sl@0: 
sl@0: // The interface used to support the STDLIB routines
sl@0: 
sl@0: wchar_t * CEnvironment::getenv(const wchar_t* aName) const
sl@0: 	{
sl@0: 	TPtrC16 name((TText16*)aName);
sl@0: 	for (TUint i=0; i<iCount; ++i)
sl@0: 		{
sl@0: 		HBufC16* value=iVars[i].Match(name);
sl@0: 		if (value)
sl@0: 			{
sl@0: 			const wchar_t* vptr = (const wchar_t*)(value->Ptr());
sl@0: 			return CONST_CAST(wchar_t*,vptr);	// I hope nobody modifies this data...
sl@0: 			}
sl@0: 		}
sl@0: 	return 0;
sl@0: 	}
sl@0: 
sl@0: int CEnvironment::setenv(const wchar_t* aName, const wchar_t* aValue, int aReplace, int& anErrno)
sl@0: 	{
sl@0: 	TPtrC16 name((TText16*)aName);
sl@0: 	TUint freeSlot=iCount;
sl@0: 	TEnvVar* ep=iVars;
sl@0: 	for (TUint i=0; i<iCount; ++i,++ep)
sl@0: 		{
sl@0: 		if (ep->NotEmpty())
sl@0: 			{
sl@0: 			const TDesC16* existing=ep->Match(name);
sl@0: 			if (existing)
sl@0: 				{
sl@0: 				TInt err=KErrNone;
sl@0: 				if (aReplace)
sl@0: 					ep->SetValue(aValue);
sl@0: 				return MapError(err,anErrno);
sl@0: 				}
sl@0: 			}
sl@0: 		else
sl@0: 			freeSlot=i;
sl@0: 		}
sl@0: 	if (freeSlot==iCount)	
sl@0: 		{
sl@0: 		// no free slots, time to grow the array
sl@0: 		ep=(TEnvVar*)User::ReAlloc(iVars,(iCount+1)*sizeof(TEnvVar));
sl@0: 		if (ep==0)
sl@0: 			return KErrNoMemory;
sl@0: 		iVars=ep;
sl@0: 		++iCount;
sl@0: 		}
sl@0: 	TRAPD(ret,iVars[freeSlot].ConstructL(name,aValue));
sl@0: 	return MapError(ret,anErrno);
sl@0: 	}
sl@0: 
sl@0: void CEnvironment::unsetenv(const wchar_t* aName)
sl@0: 	{
sl@0: 	TPtrC16 name((TText16*)aName);
sl@0: 	for (TUint i=0; i<iCount; ++i)
sl@0: 		{
sl@0: 		const TDesC16* value=iVars[i].Match(name);
sl@0: 		if (value)
sl@0: 			{
sl@0: 			iVars[i].Release();
sl@0: 			return;
sl@0: 			}
sl@0: 		}
sl@0: 	}
sl@0: