imgtools/imglib/filesystem/source/dirregion.cpp
author Richard Taylor <richard.i.taylor@nokia.com>
Thu, 03 Dec 2009 14:59:48 +0000
branchwip
changeset 32 fdfc59a2ae7e
parent 0 044383f39525
child 590 360bd6b35136
permissions -rw-r--r--
fix for broken cpp location

/*
* Copyright (c) 2006-2009 Nokia Corporation and/or its subsidiary(-ies).
* All rights reserved.
* This component and the accompanying materials are made available
* under the terms of the License "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: 
* Class receives tree structured directory and file information. And 
* prepares the cluster versus content MAP by traversing through the same. 
* Later all the prepared clusters are written into image file.
* @internalComponent
* @released
*
*/


#include "dirregion.h"

/**
Constructor:
1.Get the instance of class CCluster
2.Intializes the Cluster pointer
3.Intialize the flags and other variables

@internalComponent
@released

@param aNodeList - Root node placed in this list
@param aFileSystemPtr - CFileSystem class pointer
*/
CDirRegion::CDirRegion(EntryList aNodeList,
					   CFileSystem * aFileSystemPtr):
					   iCurrentDirEntry(false),
					   iParentDirEntry(false),
					   iFirstCluster(true),
   					   iNodeList(aNodeList)
{
	iClusterSize = aFileSystemPtr->GetClusterSize();
	iRootDirSizeInBytes = (aFileSystemPtr->GetRootDirSectors () * 
						   aFileSystemPtr->GetBytesPerSector());
	int totalClusters = aFileSystemPtr->GetTotalCluster();
	iClusterPtr = CCluster::Instance(iClusterSize,totalClusters);
	if(iClusterPtr == NULL)
	{
		throw ErrorHandler(CLUSTERERROR,"Instance creation error", __FILE__, __LINE__);
	}
	iClusterSize = iClusterPtr->GetClusterSize();
}

/**
Destructor: 
1. Clean the Node List 
2. Clean the instance of Cluster object 
3. Clean the Cluster MAP.
4. Invokes the DestroyShortEntryList to clear the contents of static GShortEntryList.

@internalComponent
@released
*/
CDirRegion::~CDirRegion()
{
	if(iNodeList.size() > 0)
	{
		//Delete the root node
		delete iNodeList.front();
	}
	if(iClusterPtr != NULL)
	{
		delete iClusterPtr;
		iClusterPtr = NULL;
	}
	iClusterMap.clear();
	ClongName::DestroyShortEntryList();
}

/**
Function to return Clusters per entry map(input for FAT table generator function) 
container

@internalComponent
@released

@return - returns clusters per entry map container
*/
TClustersPerEntryMap* CDirRegion::GetClustersPerEntryMap() const
{
	return iClusterPtr->GetClustersPerEntryMap();
}

/**
Function responsible to write all the clusters available in iClusterMap
into file. 

@internalComponent
@released

@param aOutPutStream - output file stream to write clusters in it
*/
void CDirRegion::WriteClustersIntoFile(OfStream& aOutPutStream)
{
	StringMap::iterator mapBeginIter = iClusterMap.begin();
	StringMap::iterator mapEndIter= iClusterMap.end();
	//MAPs are sorted associative containers, so no need to sort
	String tempString;
	while(mapBeginIter != mapEndIter)
	{
		tempString = (*mapBeginIter++).second;
		aOutPutStream.write(tempString.c_str(),tempString.length());
	}
	aOutPutStream.flush();
	if(aOutPutStream.bad())
	{
		throw ErrorHandler(FILEWRITEERROR, __FILE__, __LINE__);
	}
}


/**
Function takes the full entry name and formats it as per FAT spec requirement
Requirement:
1. All the names should be of 11 characters length.
2. Name occupies 8 characters and the extension occupies 3 characters.
3. If the name length is less than 8 characters, padd remaining characters with '0x20' 
4. If the extension length is less than 3 characters, padd remaining characters with '0x20' 
5. If the Name or extension exceeds from its actual length then it is treated as long name.

@internalComponent
@released

@param aString - the String needs to be formatted
@param aAttrValue - the entry attribute
*/
void CDirRegion::FormatName(String& aString, char aAttrValue)
{
	if(!aString.empty())
	{
		if((*aString.begin()) != KDot)
		{
			//Get the file extension start index
			int extensionStartIndex = aString.find_last_of (KDot);
			if(aAttrValue != EAttrDirectory && extensionStartIndex != -1)
			{
				//Erase the dot, because it is not required to be written in the FAT image
				aString.erase(extensionStartIndex,1);
				//Apply Space padding for the Name
				aString.insert (extensionStartIndex,(ENameLength - extensionStartIndex), KSpace);
				int totalStringLength = aString.length();
				//Apply Space padding for the  Extension
				if(totalStringLength < ENameLengthWithExtension)
				{
					aString.insert(totalStringLength,(ENameLengthWithExtension - totalStringLength), KSpace);
					return;
				}
			}
			else
			{
				int nameEndIndex = aString.length();
				//Apply Space padding for the directory Name
				aString.insert(nameEndIndex,(ENameLengthWithExtension - nameEndIndex),KSpace);
				return;
			}
		}
		else
		{	//Apply Space padding for either '.' or ".."
			aString.append((ENameLengthWithExtension - aString.length()),KSpace);
			return;
		}
	}
	else
	{
		throw ErrorHandler(EMPTYFILENAME, __FILE__, __LINE__);
	}
}

/**
Function responsible to classify the entry name as long name or regular name.

@internalComponent
@released

@param aEntry - the directory entry
@return - returns true if it is long name else false.
*/
bool CDirRegion::IsLongEntry(CDirectory* aEntry) const
{
	String entryName = aEntry->GetEntryName();
	unsigned int receivedNameLength = entryName.length();
	unsigned int firstDotLocation = entryName.find_first_of(KDot);
	unsigned int lastDotLocation = entryName.find_last_of(KDot);

	if(firstDotLocation == lastDotLocation)
	{
		if(aEntry->GetEntryAttribute() == EAttrDirectory)
		{
			// If the directory name length is more than 8 characters, then it is a long name
			if(receivedNameLength > ENameLength)
			{
				return true;
			}
		}
		else
		{
			int extensionIndex = lastDotLocation;
			unsigned int fileExtensionLength = receivedNameLength - extensionIndex - 1;
			/*Either the full name length is greater than 11 or the extension 
			 *length is greater than 3, then it is considered as long name.
			 */
			if((receivedNameLength > ENameLengthWithExtension) 
			   || (fileExtensionLength > EExtensionLength))
			{
				return true;
			}
		}
		return false;
	}
	else
	{
		//If the name contains multiple dots, then it is a long name.
		return true;	
	}
}

/**
Function responsible to 
1. Invoke long name class
2. Invoke the methods to create long and short entries
3. Receive the string filled with long entries

@internalComponent
@released

@param aEntry - the entry
@param aDirString - long name entry appended to this string
*/

void CDirRegion::CreateLongEntries(CDirectory* aEntry,String& aDirString)
{
	ClongName aLongNameObject(iClusterPtr,aEntry);
	String tempString = aLongNameObject.CreateLongEntries();
	if(tempString.length() == 0)
	{
		tempString.erase();
		throw ErrorHandler(EMPTYFILENAME, __FILE__, __LINE__);
	}
	else
	{
		aDirString.append(tempString.c_str(),tempString.length());
		tempString.erase();
		WriteEntryToString(aLongNameObject.CreateShortEntry(aEntry),aDirString);
	}
}

/**
Function takes a single entry and writes its attributes into tempString.
Later this string is appended with the string received in the argument

@internalComponent
@released

@param aEntry - the entry which attributes are needs to be written into aString
@param aString - entry attributes appended into this string
*/
void CDirRegion::WriteEntryToString(CDirectory* aEntry,String& aString)
{
	String tempString;
	String entryName = aEntry->GetEntryName();
	tempString.append(ToUpper(entryName));
	//appends the attributes only once
	tempString.append(KWriteOnce, aEntry->GetEntryAttribute());
	tempString.append(KWriteOnce, aEntry->GetNtReservedByte());
	tempString.append(KWriteOnce, aEntry->GetCreationTimeMsecs());
	unsigned short int createdTime = aEntry->GetCreatedTime();
	tempString.append(ToString(createdTime));
	unsigned short int creationDate = aEntry->GetCreationDate();
	tempString.append(ToString(creationDate));
	unsigned short int lastAccessDate = aEntry->GetLastAccessDate();
	tempString.append(ToString(lastAccessDate));
	unsigned short int clusterNumberHi = aEntry->GetClusterNumberHi();
	tempString.append(ToString(clusterNumberHi));
	unsigned short int lastWriteTime = aEntry->GetLastWriteTime();
	tempString.append(ToString(lastWriteTime));
	unsigned short int lastWriteDate = aEntry->GetLastWriteDate();
	tempString.append(ToString(lastWriteDate));
	unsigned short int clusterNumberLow = aEntry->GetClusterNumberLow();
	tempString.append(ToString(clusterNumberLow));
	unsigned int fileSize = aEntry->GetFileSize();
	tempString.append(ToString(fileSize));

	aString.append(tempString.c_str(),KDirectoryEntrySize);
	tempString.erase();
}

 

/**
Function responsible to 
1. Read the file content and write into string.
2. Invoke the function to push data clusters into cluster Map

@internalComponent
@released

@param aEntry - the directory entry node
*/
void CDirRegion::WriteFileDataInToCluster(CDirectory* aEntry)
{
	iInputStream.open(aEntry->GetFilePath().c_str(),Ios::binary);
	if(iInputStream.fail() == true )
	{
		throw ErrorHandler(FILEOPENERROR,(char*)aEntry->GetFilePath().c_str(),__FILE__,__LINE__);
	}
	else
	{
		iInputStream.seekg (0,Ios::end);
		Long64 fileSize = iInputStream.tellg(); 
		iInputStream.seekg(0,Ios::beg);
		char* dataBuffer = (char*)malloc((unsigned int)fileSize);
		if(dataBuffer == 0)
		{
			throw ErrorHandler(MEMORYALLOCATIONERROR, __FILE__, __LINE__);
		}
		//Read the whole file in one short
		iInputStream.read (dataBuffer,fileSize);
		
		Long64 bytesRead = (unsigned int)iInputStream.tellg();
		if((iInputStream.bad()) || (bytesRead != fileSize))
		{
			throw ErrorHandler(FILEREADERROR,(char*)aEntry->GetFilePath().c_str(), __FILE__, __LINE__);
		}
		String clusterData(dataBuffer,(unsigned int)bytesRead);
		PushStringIntoClusterMap(iClusterPtr->GetCurrentClusterNumber(),clusterData,iClusterSize,aEntry->GetEntryAttribute());
	}
	iInputStream.close();
}


/**
Function invokes 
1. CheckEntry function, to identify whether the received entry list is proper or not.
2. Invokes CreateDirEntry, to create directory and data portion of FAT image.

@internalComponent
@released
  
*/
void CDirRegion::Execute()
{
	CheckEntry(iNodeList);
	CreateDirEntry(iNodeList.front(),KParentDirClusterNumber);
}

/**
Function is to initialize the Parent directory entry with parent cluster number
and appends all the attributes into the string (aString).

@internalComponent
@released

@param aParDirClusterNumber - parent directory cluster number
@param aString - parent directory entry attributes appended to this string
*/
void CDirRegion::CreateAndWriteParentDirEntry(unsigned int aParDirClusterNumber,String& aString)
{
	const char* parentDirName = ".."; //Indicates parent directory entry name
	CDirectory* parentDirectory = new CDirectory((char*)parentDirName);

	parentDirectory->SetEntryAttribute(EAttrDirectory);
	parentDirectory->SetClusterNumberLow((unsigned short) (aParDirClusterNumber & KHighWordMask));
	parentDirectory->SetClusterNumberHi((unsigned short) (aParDirClusterNumber >> KBitShift16));

	String tempString(parentDirectory->GetEntryName());
	FormatName(tempString,EAttrDirectory);
	parentDirectory->SetEntryName(tempString);
	tempString.erase();
	
	WriteEntryToString(parentDirectory,aString);
	iParentDirEntry = true;
	delete parentDirectory;
	parentDirectory = NULL;
}

/**
Function responsible to 
1. Initialize the Current directory entry attribute
2. Write the entry attributes into received string

@internalComponent
@released

@param aCurDirClusterNumber - Current directory Cluster number
@param aString - the entry attributes should be appended to this string
*/
void CDirRegion::CreateAndWriteCurrentDirEntry(unsigned int aCurClusterNumber,String& aString)
{
	const char* currentDirName = "."; //Indicates Current Directory entry name
	iCurEntryClusterNumber = aCurClusterNumber;
	CDirectory* currentDirectory = new CDirectory((char*)currentDirName);

	currentDirectory->SetEntryAttribute(EAttrDirectory);
	currentDirectory->SetClusterNumberLow((unsigned short) (iCurEntryClusterNumber & KHighWordMask));
	currentDirectory->SetClusterNumberHi((unsigned short) (iCurEntryClusterNumber >> KBitShift16));

	String tempString(currentDirectory->GetEntryName());
	FormatName(tempString,EAttrDirectory);
	currentDirectory->SetEntryName(tempString);
	tempString.erase();

	WriteEntryToString(currentDirectory,aString);
	iCurrentDirEntry = true;
	delete currentDirectory;
	currentDirectory = NULL;
}

/**
Function responsible to push the directory entry clusters into cluster MAP only if the
directory entry string size is greater than the cluster size.

@internalComponent
@released

@param aNumber - is the Cluster Key used to insert the cluster into cluster map
@param aString - is the directory entry string
@param aClustersRequired - No of clusters required to hold this string
*/

void CDirRegion::PushDirectoryEntryString(unsigned int aNumber,String& aString,int aClustersRequired)
{
	int clusterCount = 0;
	int clusterKey = aNumber;
	iClusterPtr->CreateMap(aNumber,clusterKey);
	iClusterMap[clusterKey] =	aString.substr(clusterCount*iClusterSize,iClusterSize);
	++clusterCount;
	String clusterSizeString;
	for(; clusterCount < aClustersRequired; ++clusterCount)
	{
		clusterKey = iClusterPtr->GetCurrentClusterNumber();
		clusterSizeString = aString.substr(clusterCount*iClusterSize,iClusterSize);
		clusterSizeString.append((iClusterSize - clusterSizeString.length()),0);
		iClusterMap[clusterKey] = clusterSizeString;
		iClusterPtr->CreateMap(aNumber,clusterKey);
		iClusterPtr->UpdateNextAvailableClusterNumber();
	}
}

/**Function responsible to 
1. Convert the string into equal size clusters of cluster size
2. Insert the clusters into Cluster MAP

@internalComponent
@released

@param aNumber - cluster number, used to map the cluster
@param aString - reference of input string
@param aClusterSize - used to split the string
@param aAttribute - current entry attribute
*/
void CDirRegion::PushStringIntoClusterMap(unsigned int aNumber, String& aString, unsigned long int aClusterSize,char aAttribute)
{
	int receivedStringLength = aString.length();
	/* Precaution, once the map is initialized with specific cluster number don't over write
	 * it once again. Look for the cluster number within the existing MAP and then proceed with 
	 * filling in the cluster.
	 */
	StringMap::iterator iter= iClusterMap.find(aNumber);
	if(iter == iClusterMap.end())
	{
		/* The length of the cluster content (aString) can be more or less than the cluster size, 
		 * hence, calculate the total number of clusters required.
		 */
		int clustersRequired = receivedStringLength / aClusterSize;
		if((receivedStringLength % aClusterSize) > 0)
		{
			++clustersRequired;
		}
		if((clustersRequired > 1) && (aAttribute == EAttrDirectory))
		{
			PushDirectoryEntryString(aNumber,aString,clustersRequired);
			return;
		}
		int updatedClusterNumber = aNumber;
		String clusterSizeString;
		for(short int clusterCount = 0; clusterCount < clustersRequired; ++clusterCount)
		{
			/* In case of the contents occupying more than one cluster, break the contents into
			 * multiple parts, each one measuring as that of the cluster size.
			 */
			clusterSizeString = aString.substr(clusterCount * aClusterSize,aClusterSize);
			iClusterPtr->CreateMap(aNumber,updatedClusterNumber);
			if(clusterSizeString.length() < aClusterSize)
			{
				/* Copied string size is less than cluster size, fill the remaining space
				 * with zero
				 */
				clusterSizeString.append((aClusterSize - clusterSizeString.length()),0);
			}
			// Insert the String into ClusterMap	
			iClusterMap[updatedClusterNumber] = clusterSizeString;
		
			iClusterPtr->UpdateNextAvailableClusterNumber();
			updatedClusterNumber = iClusterPtr->GetCurrentClusterNumber ();
		}
		/* In the above loop, cluster number is incremented to point to the next entry.
		 * However, before writing a directory or a volume id entry, it is always ensured 
		 * to get the next cluster number. Hence in this case, it is required to decrement
		 * the cluster number, so that the pointer points to the end of the cluster occupied.
		 */
		if(aAttribute == EAttrDirectory || aAttribute == EAttrVolumeId)
		{
			iClusterPtr->DecrementCurrentClusterNumber ();
		}
	}
}

/**
Function is responsible to take in the tree structured directory 
information and to initialize the starting cluster in the Cluster Map.

@internalComponent
@released

@param aNodeList - the list which holds root entry
*/
void CDirRegion::CheckEntry(EntryList aNodeList)
{
	if(aNodeList.size() > 0)
	{
		if(iRootDirSizeInBytes > 0)
		{
			//FAT16 Root entries are written into Cluster 1
			iClusterKey = KFat16RootEntryNumber;
		}
		else
		{
			//FAT32 Root entries are written into Cluster 2			
			iClusterPtr->UpdateNextAvailableClusterNumber();
			iClusterKey = KFat32RootEntryNumber; 
		}
		if(aNodeList.front()->GetEntryList()->size() <= 0)
		{
			throw ErrorHandler(NOENTRIESFOUND, __FILE__, __LINE__);
		}
	}
	else
	{
		throw ErrorHandler(ROOTNOTFOUND, __FILE__, __LINE__);
	}
}

/**
Function receives Tree structured folder information and does the following:
1. Generates Directory Entry portion of FAT image recursively.
2. If it finds the entry as file then writes its contents.
3. If the entry is long name then longfilename class invoked to create long entries.

@internalComponent
@released

@param aEntry  - Subdirectory pointer of root directory
@param aParentDirClusterNumber - parent directory cluster number
*/
void CDirRegion::CreateDirEntry(CDirectory* aEntry,unsigned int aParentDirClusterNumber)
{
	unsigned int currentDirClusterNumber = 0;
	int rootClusterSize = 0;
	if(iFirstCluster == true)
	{
			iCurrentDirEntry = true;
			iParentDirEntry = true;
			/**Root directory and Normal directory has one difference.
			FAT16 : Root cluster occupies 32 sectors
			FAT32 : Root cluster occupies only one cluster
			*/
			rootClusterSize = (iRootDirSizeInBytes > 0)?iRootDirSizeInBytes:iClusterSize; 
	}
	else
	{
		currentDirClusterNumber = Get32BitClusterNumber(aEntry->GetClusterNumberHi(),
														aEntry->GetClusterNumberLow());
	}
	
	//printIterator used while printing the entries
	EntryList::iterator printIterator = aEntry->GetEntryList()->begin(); 
	//traverseIterator used during recursive call
	EntryList::iterator traverseIterator = printIterator;
	
	unsigned int dirEntryCount = aEntry->GetEntryList()->size();

	String dirString;
	String nameString;
	CDirectory* tempDirEntry = (*printIterator);
	//Writes all the Directory entries available in one Directory entry
	while(dirEntryCount > 0)
	{
		tempDirEntry = (*printIterator);
		
		tempDirEntry->SetClusterNumberHi(iClusterPtr->GetHighWordClusterNumber());
		tempDirEntry->SetClusterNumberLow(iClusterPtr->GetLowWordClusterNumber());

		/* Every directory should have current and parent directory entries in its
		 * respective cluster. Hence Create the current and parent directory entries 
		 * only if it is not created already.
		 */
		if(!iCurrentDirEntry && !iParentDirEntry)
		{
			CreateAndWriteCurrentDirEntry(currentDirClusterNumber,dirString);
			iClusterKey = currentDirClusterNumber;
			CreateAndWriteParentDirEntry(aParentDirClusterNumber,dirString);
		}
		MessageHandler::ReportMessage(INFORMATION,
									  ENTRYCREATEMSG,
									  (char*)tempDirEntry->GetEntryName().c_str());
		if(!IsLongEntry(tempDirEntry))
		{
			nameString.assign(tempDirEntry->GetEntryName());
			FormatName(nameString,tempDirEntry->GetEntryAttribute());
			tempDirEntry->SetEntryName(nameString);
			nameString.erase();
			WriteEntryToString(tempDirEntry,dirString);
		}
		else
		{
			CreateLongEntries(tempDirEntry,dirString);
		}
		if(tempDirEntry->IsFile())
		{
			WriteFileDataInToCluster(tempDirEntry);
		}
		else
		{
			iClusterPtr->UpdateNextAvailableClusterNumber ();
		}
		++printIterator;
		--dirEntryCount;
	}

	iCurrentDirEntry = false;
	iParentDirEntry = false;
	aParentDirClusterNumber = currentDirClusterNumber;
	if(iFirstCluster == true)
	{
		PushStringIntoClusterMap(iClusterKey,dirString,rootClusterSize,aEntry->GetEntryAttribute());
		iFirstCluster = false;
	}
	else
	{
		PushStringIntoClusterMap(iClusterKey,dirString,iClusterSize,aEntry->GetEntryAttribute());
	}

	dirEntryCount = aEntry->GetEntryList()->size();

	//Recursive algorithm to print all entries
	while(dirEntryCount > 0)
	{
		if(aEntry->GetEntryList()->size() > 0)
		{		
			CreateDirEntry((*traverseIterator),aParentDirClusterNumber);
		}
		--dirEntryCount;
		//if no entries found don't go deep
		if(dirEntryCount > 0)
		{
			aEntry = (*++traverseIterator);
		}
	}
}

/**
Function responsible to convert two 16 bit words into single 32 bit integer

@internalComponent
@released

@param aHighWord - 16 bit high word
@param aLowWord - 16 bit low word
@return returns the 32 bit integer
*/
unsigned int CDirRegion::Get32BitClusterNumber(unsigned int aHighWord, unsigned int aLowWord)
{
	unsigned int clusterNumber = aHighWord;
	clusterNumber <<= KBitShift16;
	clusterNumber |= aLowWord;
	return clusterNumber;
}