// Copyright (c) 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:

//	Classes that allow the editing and creation of Symbian ELF files

//

/**

 * @file selflib.cpp

 * @prototype

 */

#include <f32file.h>

#include "selflib.h"

#include "debuglogging.h"

#include "symbianelfstringinfov2.h"

#include "symbianelfstringinfo.h"

/**

 * First stage construction

 * @return Pointer to new CSELFEditor object

 * @leave One of the System Wide Error Codes

 */

EXPORT_C CSELFEditor* CSELFEditor::NewL(const TDesC& aFilename)

	{

	LOG_ENTRY();

	CSELFEditor* self = CSELFEditor::NewLC(aFilename);

	CleanupStack::Pop();

	return self;

	}

/**

 * First stage construction. Object is left upon cleanup stack

 * @return Pointer to new CSELFEditor object

 * @leave One of the System Wide Error Codes

 */

EXPORT_C CSELFEditor* CSELFEditor::NewLC(const TDesC& aFilename)

	{

	LOG_ENTRY();

	CSELFEditor* self = new(ELeave)CSELFEditor();

	CleanupStack::PushL(self);

	self->ConstructL(aFilename);

	return self;

	}

/**

 * CSELFEditor Desctructor

 */

CSELFEditor::~CSELFEditor()

	{

	LOG_ENTRY();

	delete iRawData;

	delete iStringTable;

	iELFFile.Close();

	iFsSession.Close();

	iNewSegments.Close();

	iProgramHeaders.Close();

	}

/**

 * Second stage safe construction

 * @leave One of the System Wide Error Codes

 */

void CSELFEditor::ConstructL(const TDesC& aFilename)

	{

	LOG_ENTRY();

	User::LeaveIfError(iFsSession.Connect());

	User::LeaveIfError(iELFFile.Open(iFsSession, aFilename, EFileWrite));

	TInt fileSize;

	User::LeaveIfError(iELFFile.Size(fileSize));

	//Check its big enough to at least read the header

	if(fileSize < sizeof(Elf32_Ehdr))

		{

		LOG_MSG("\tCSELFEditor::ConstructL --> File is not big enough to be an ELF file");

		User::Leave(KErrCorrupt);

		}

	CacheELFHeaderL();

	//Validate the ELF file

	if(!IsValidELFFile())

		User::Leave(KErrCorrupt);

	if(!IsELFFileSupported())

		User::Leave(KErrNotSupported);

	iRawData = new(ELeave) CDesC8ArrayFlat(1);

	CacheProgramHeadersL();

	CacheStringTableL();

	}

/**

 * Caches ELF File internally in this object

 * @see GetELFHeader

 * @leave One of the system wide error codes

 */

void CSELFEditor::CacheELFHeaderL()

	{

	//Read the ELF header

	TUint fileLocation = 0;

	TPtr8 hdrDes((TUint8*)&iELFHeader, sizeof(Elf32_Ehdr));

	User::LeaveIfError(iELFFile.Read(fileLocation, hdrDes));

	}

/**

 * CSELFEditor Constructor

 */

CSELFEditor::CSELFEditor()

	{}

/**

 * This ELF library currently only supports a specific subset of the ELF standard.

 * This function makes sure the ELF file supplied is part of that subset. These are the things

 * we do not currently support:

 * 1. 64 Bit ELF

 * 2. ELFDATA2MSB File class (Big Endian)

 * 3. Any sections

 * 4. Any type other than ET_CORE

 *

 * @return TBool indicating if the file is OK to continue with

 */

TBool CSELFEditor::IsELFFileSupported()

	{

	LOG_ENTRY();

	TBool supported = ETrue;

	if(iELFHeader.e_ident[EI_CLASS] != ELFCLASS32)

		{

		LOG_MSG("\tCSELFEditor::IsElfFileSupported() --> Non 32 bit files are not supported");

		supported = EFalse;

		}

	if(iELFHeader.e_ident[EI_DATA] != ELFDATA2LSB)

		{

		LOG_MSG("\tCSELFEditor::IsElfFileSupported() --> Only support Little Endian");

		supported = EFalse;

		}

	if(iELFHeader.e_type != ET_CORE)

		{

		LOG_MSG("\tCSELFEditor::IsElfFileSupported() --> Only support Core Files");

		supported = EFalse;

		}

	if(iELFHeader.e_shoff != 0 || iELFHeader.e_shnum != 0)

		{

		LOG_MSG("\tCSELFEditor::IsElfFileSupported() --> Do not support Sections");

		supported = EFalse;

		}

	return supported;

	}

/**

 * Validates the ELF file by looking at the signature

 * @return Boolean indicating whether or not the file is valid ELF

 */

TBool CSELFEditor::IsValidELFFile()

	{

	LOG_ENTRY();

	//Check signature

	return iELFHeader.e_ident[EI_MAG0] == ELFMAG0 &&

		iELFHeader.e_ident[EI_MAG1] == ELFMAG1 &&

		iELFHeader.e_ident[EI_MAG2] == ELFMAG2 &&

		iELFHeader.e_ident[EI_MAG3] == ELFMAG3;

	}

/**

 * Provides the ELF header of this file

 * @param aELFHeader Holds the ELF header after the call

 */

EXPORT_C void CSELFEditor::GetELFHeader(Elf32_Ehdr& aELFHeader)

	{

	LOG_ENTRY();

	aELFHeader = iELFHeader;

	}

/**

 * Caches the program headers from the file into this object

 * @leave One of the system wide codes

 */

void CSELFEditor::CacheProgramHeadersL()

	{

	LOG_ENTRY();

	Elf32_Phdr progHeader;

	TPtr8 phdrPtr((TUint8*)&progHeader, sizeof(Elf32_Phdr));

	TUint nextPh = iELFHeader.e_phoff;

	for(TUint i = 0; i < iELFHeader.e_phnum; i++)

		{

		User::LeaveIfError(iELFFile.Read(nextPh, phdrPtr));

		iProgramHeaders.AppendL(progHeader);

		nextPh += sizeof(Elf32_Phdr);

		}

	}

/**

 * Inserts variant specific data into the ELF file

 * @param aVarData The binary data to be inserted into the ELF file

 * @leave One of the system wide codes

 */

EXPORT_C void CSELFEditor::InsertVariantSpecificDataL(const TDesC8& aVarData)

	{

	LOG_ENTRY();

	//Store the data in the raw data array, and record its position to associate with the new section

	iRawData->AppendL(aVarData);

	TUint position = iRawData->Count() - 1;

	//Now create the variant sepcific data dhdr and structure

	TSELFSegment newSegment;

	newSegment.iPhdr.p_type = PT_NOTE;

	newSegment.iPhdr.p_offset = 0;    //Fill in when we write the file

	newSegment.iPhdr.p_vaddr = 0;

	newSegment.iPhdr.p_paddr = 0;

	newSegment.iPhdr.p_filesz =0;

	newSegment.iPhdr.p_memsz = 0;

	newSegment.iPhdr.p_flags = 0;

	newSegment.iPhdr.p_align = sizeof(TUint);

	newSegment.iDhdr.d_name = 0;		//Fill in when we write the file (we need the string table)

	newSegment.iDhdr.d_type = ESYM_NOTE_VARIANT_DATA;

	newSegment.iDhdr.d_version = 0;	//Fill in when we write the file (we need the string table)

	newSegment.iDhdr.d_elemnum = 1;

	newSegment.iDhdr.d_descrsz = sizeof(Sym32_variant_spec_data);

	Sym32_variant_spec_data* variantData = (Sym32_variant_spec_data*)(&newSegment.iType);

	variantData->es_data = position;			//This data is in the iRawData until the write

	variantData->es_size = aVarData.Size();

	iNewSegments.AppendL(newSegment);

	++iELFHeader.e_phnum;

	}

/**

 * Commits any changes made in the CSELFEditor to the ELF file

 * @leave One of the system wide codes

 */

EXPORT_C void CSELFEditor::WriteELFUpdatesL()

	{

	LOG_ENTRY();

	//There may be nothing to do

	if(iNewSegments.Count() == 0)

		return;

	//Create tmp file

	TBuf<KMaxFileName> tmpFilename;

	RFile tmpFile;

	User::LeaveIfError(tmpFile.Temp(iFsSession, KTempFileLocation, tmpFilename, EFileWrite));

	CleanupClosePushL(tmpFile);

	//Log file name

	TPtr8 smallName((TUint8*)tmpFilename.Ptr(), 2*tmpFilename.Length(), 2*tmpFilename.Length());

	LOG_MSG2("\tWriteELFUpdatesL() --> Writing new temporary updates to [%S]", &smallName);

	TUint numberofPhdrs = 0;

	//Leave space for elf header plus program header table at start

	TUint spaceToLeave =+ sizeof(Elf32_Ehdr) + (iNewSegments.Count() + iProgramHeaders.Count() ) * sizeof(Elf32_Phdr);

	PutEmptySpaceAtEndOfFileL(tmpFile, spaceToLeave);

	TUint phdrLoc = sizeof(Elf32_Ehdr); //phdr table starts just after ELF header

	TUint dataLoc = spaceToLeave;

	LOG_MSG("WriteELFUpdatesL --> Copying existing program headers to the tmp file");

	//Store new program headers as we go

	RArray<Elf32_Phdr> newProgramHeaders;

	{

	Elf32_Phdr phdr;

	TPtr8 phdrPtr((TUint8*)&phdr, sizeof(Elf32_Phdr), sizeof(Elf32_Phdr));

	for(TUint i = 0; i < iProgramHeaders.Count(); i++)

		{

		phdr = iProgramHeaders[i];

		//Now we put the neccesary data after the phdr table

		if(phdr.p_type == PT_LOAD && phdr.p_filesz != 0 && phdr.p_offset != 0)

			{

			phdr.p_offset = CopyFromELFFileL(phdr.p_offset, phdr.p_filesz, tmpFile, dataLoc);

			dataLoc += phdr.p_filesz;

			}

		else if(phdr.p_type == PT_NOTE)

			{

			//Read the symbian descriptor

			READ_STRUCTL(Sym32_dhdr, symd, iELFFile, phdr.p_offset);

			//TODO: The fact that we need this *MAY* indicate flaws in SELF format. It would be nice

			//to be able to copy a bit that was completely described by the dhdr

			if(symd.d_type == ESYM_NOTE_REG)

				{

				//registers cant just be blindly copied as they contain offsets that need updating

				TUint sizeWritten = 0;

				phdr.p_offset = CopyRegistersL(tmpFile, phdr.p_offset, dataLoc, sizeWritten);

				dataLoc += sizeWritten;

				}

			else if(symd.d_type == ESYM_NOTE_VARIANT_DATA)

				{

				//Variant data cant be blindly copied either as they have offsets too

				TUint sizeWritten = 0;

				phdr.p_offset = CopyVariantDataL(tmpFile, phdr.p_offset, dataLoc, sizeWritten);

				dataLoc += sizeWritten;

				}

			//special case - needs updating so do after everything else

			else if(symd.d_type == ESYM_NOTE_STR)

				{

				continue;

				}

			else

				{

				TUint sizetoCopy = sizeof(Sym32_dhdr) + symd.d_descrsz * symd.d_elemnum;

				phdr.p_offset = CopyFromELFFileL(phdr.p_offset, sizetoCopy, tmpFile, dataLoc);

				dataLoc += sizetoCopy;

				}

			}

		//Write the updated program header

 		User::LeaveIfError(tmpFile.Write(phdrLoc, phdrPtr));

		phdrLoc += sizeof(Elf32_Phdr);

		newProgramHeaders.AppendL(phdr);

		++numberofPhdrs;

		}

	LOG_MSG2("WriteELFUpdatesL --> Copied [%d] existing program headers (minus string table)", numberofPhdrs);

	}

	//Now we add the new segments

	//This is for the string table

	TBuf8<KMaxFileName> varDataBuf;

	varDataBuf.Format(_L8("CORE.SYMBIAN.VARDATA"));

	TUint versionIndex = iStringTable->GetIndex(KSymbianElfCoreDumpVersionV2);

	for(TUint i = 0; i < iNewSegments.Count(); i++)

		{

		TSELFSegment segment = iNewSegments[i];

		//Update the program header and the d_hdr

		segment.iPhdr.p_offset = dataLoc;

		TInt index = iStringTable->AddStringL(varDataBuf);

		segment.iDhdr.d_name = (index == KErrNotFound) ? ESYM_STR_UNDEF : index;

		segment.iDhdr.d_version = versionIndex;

		Sym32_variant_spec_data* variantData = (Sym32_variant_spec_data*)(&segment.iType);

		TUint dataIndex = variantData->es_data;

		variantData->es_data = dataLoc + sizeof(Sym32_variant_spec_data) + sizeof(Sym32_dhdr);

		//Write the phdr

		TPtr8 nphdrPtr((TUint8*)&segment.iPhdr, sizeof(Elf32_Phdr), sizeof(Elf32_Phdr));

		User::LeaveIfError(tmpFile.Write(phdrLoc, nphdrPtr));

		newProgramHeaders.AppendL(segment.iPhdr);

		phdrLoc += sizeof(Elf32_Phdr);

		++numberofPhdrs;

		//Write the dhdr

		TPtr8 ndhdrPtr((TUint8*)&segment.iDhdr, sizeof(Sym32_dhdr), sizeof(Sym32_dhdr));

		User::LeaveIfError(tmpFile.Write(dataLoc, ndhdrPtr));

		dataLoc += sizeof(Sym32_dhdr);

		//Write the var struct

		TPtr8 nvarHdr((TUint8*)&segment.iType, sizeof(Sym32_variant_spec_data), sizeof(Sym32_variant_spec_data));

		User::LeaveIfError(tmpFile.Write(dataLoc, nvarHdr));

		dataLoc += sizeof(Sym32_variant_spec_data);

		//Write the data

		User::LeaveIfError(tmpFile.Write(dataLoc, (*iRawData)[dataIndex]));

		dataLoc += variantData->es_size;

		}

	//Write the string info

	Elf32_Phdr sphdr;

	TPtr8 sphdrPtr((TUint8*)&sphdr, sizeof(Elf32_Phdr), sizeof(Elf32_Phdr));

	sphdr.p_type = PT_NOTE;

	sphdr.p_offset = WriteStringInfoL(tmpFile, dataLoc);

	sphdr.p_vaddr = 0;

	sphdr.p_paddr = 0;

	sphdr.p_filesz = 0;

	sphdr.p_memsz = 0;

	sphdr.p_flags = 0;

	sphdr.p_align = 4;

	User::LeaveIfError(tmpFile.Write(phdrLoc, sphdrPtr));

	newProgramHeaders.Append(sphdr);

	phdrLoc += sizeof(Elf32_Phdr);

	++numberofPhdrs;

	//Last thing, is to finally update the ELF header and write it

	iELFHeader.e_phoff = sizeof(Elf32_Ehdr);

	iELFHeader.e_phnum = numberofPhdrs;

	LOG_MSG("\tWriting final ELF Header");

	TPtr8 hdrPtr((TUint8*)&iELFHeader, sizeof(Elf32_Ehdr), sizeof(Elf32_Ehdr));

	User::LeaveIfError(tmpFile.Write(0, hdrPtr));

	tmpFile.Flush();

	CleanupStack::PopAndDestroy(&tmpFile);

	TBuf<KMaxFileName> origFilename;

	iELFFile.FullName(origFilename);

	iELFFile.Close();

	SwapFilesL(tmpFilename, origFilename);

	//Open the file again for further use and reset data structs

	User::LeaveIfError(iELFFile.Open(iFsSession, origFilename, EFileWrite));

	iNewSegments.Reset();

	iProgramHeaders.Close();

	iProgramHeaders = newProgramHeaders;  //Update with latest p hdrs

	}

/**

 * Writes the string info at specified offset

 * This writes the Sym32_dhdr and the string info

 * @param aFile File to write to

 * @param aOffset Position in file to write to. This is updated and finishes at the next free point to

 * write to in this file

 * @leave One of the system wide codes

 * @return Offset in the file where this was written to (the initial value of aOffset)

 */

TUint CSELFEditor::WriteStringInfoL(RFile aFile, TUint& aOffset)

	{

	LOG_ENTRY();

	TUint writeStart = aOffset;

	Sym32_dhdr dhdr;

	TPtr8 dhdrPtr((TUint8*)&dhdr, sizeof(Sym32_dhdr), sizeof(Sym32_dhdr));

	TInt index = iStringTable->GetIndex(KStr);

	dhdr.d_name		= (index == KErrNotFound) ? ESYM_STR_UNDEF : index;

	dhdr.d_descrsz	= iStringTable->GetSize();

	dhdr.d_type		= ESYM_NOTE_STR;

	dhdr.d_version	= iStringTable->GetIndex(KSymbianElfCoreDumpVersionV2);

    dhdr.d_elemnum	= 1;

	//Write the dhdr

	User::LeaveIfError(aFile.Write(aOffset, dhdrPtr));

	aOffset += sizeof(Sym32_dhdr);

	//Write the string info

	TText8* buf = iStringTable->GetAllStrings();

	TUint size = iStringTable->GetSize();

	TPtr8 data((TUint8*)buf, size, size);

	User::LeaveIfError(aFile.Write(aOffset, data));

	aOffset += size;

	return writeStart;

	}

/**

 * Copies the registers to aFile sensibly, updating the offsets accordingly

 * @param aFile Destination file

 * @param aSrcRead Place in src file where d_hdr starts

 * @param aDestWrite Destination to write to

 * @leave One of the system wide codes

 */

TUint CSELFEditor::CopyRegistersL(RFile aFile, TUint aSrcRead, TUint aDestWrite, TUint& aSizeWritten)

	{

	LOG_ENTRY();

	aSizeWritten = 0;

	TUint srcpos = aSrcRead;

	TUint destpos = aDestWrite;

	//Write the dhdr, it wont change

	READ_STRUCTL(Sym32_dhdr, dhdr, iELFFile, srcpos);

	CopyFromELFFileL(srcpos, sizeof(Sym32_dhdr), aFile, destpos);

	srcpos += sizeof(Sym32_dhdr);

	destpos += sizeof(Sym32_dhdr);

	//And the reginfod struct

	READ_STRUCTL(Sym32_reginfod, reginfo, iELFFile, srcpos);

	CopyFromELFFileL(srcpos, sizeof(Sym32_reginfod), aFile, destpos);

	srcpos += sizeof(Sym32_reginfod);

	destpos += sizeof(Sym32_reginfod);

	RBuf8 regVals;

	regVals.CreateL(reginfo.rid_num_registers * sizeof(TUint64));

	regVals.CleanupClosePushL();

	//Now we need to go through the individual register values. They are offset to somewhere and

	//we need to figure out where we will be putting them first

	TUint regoffset = destpos + (reginfo.rid_num_registers * sizeof(Sym32_regdatad) );

	for(TUint i = 0; i < reginfo.rid_num_registers; i++)

		{

		READ_STRUCTL(Sym32_regdatad, regdata, iELFFile, srcpos);

		srcpos += sizeof(Sym32_regdatad);

		//update the offset

		TUint srcOffset = regdata.rd_data;

		regdata.rd_data = regoffset;

		regoffset += sizeof(TUint64);

		//Write it to the file

		TPtr8 dataPtr((TUint8*)&regdata, sizeof(Sym32_regdatad), sizeof(Sym32_regdatad));

		User::LeaveIfError(aFile.Write(destpos, dataPtr));

		destpos += sizeof(Sym32_regdatad);

		//Read the appropriate value