--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/imgtools/imgcheck/src/hash.cpp	Tue Oct 27 16:36:35 2009 +0000
@@ -0,0 +1,177 @@
+/*
+* 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 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: 
+* Hash class for imgcheck tool. All the executable names of ROM/ROFS 
+* are stored into this hash table. After gathering the dependencies
+* for those executables, dependencies existence is checked very 
+* efficiently using this table.
+*
+*/
+
+
+/**
+ @file
+ @internalComponent
+ @released
+*/
+
+#include "common.h"
+#include "hash.h"
+
+/** 
+Constructor, intializes the table size
+
+@internalComponent
+@released
+
+@param aSize - Hash table size (Number of dissimilar data can stored)
+*/
+HashTable::HashTable(int aSize)
+:iSize(aSize)
+{
+}
+
+/** 
+Destructor
+
+@internalComponent
+@released
+*/
+HashTable::~HashTable()
+{
+}
+
+/** 
+Function responsible to return the Hash value for the received string.
+
+@internalComponent
+@released
+
+@param aString - String on which Hash value calcualtion to be done
+*/
+int HashTable::Hash(String aString)
+{
+	unsigned int hashVal = 0;
+	int length = aString.length();
+	/* we start our hash out at 0 */
+
+	/* for each character, we multiply the old hash by 31 and add the current
+	 * character.  Remember that shifting a number left is equivalent to 
+	 * multiplying it by 2 raised to the number of places shifted.  So we 
+	 * are in effect multiplying hashval by 32 and then subtracting hashval.  
+	 * Why do we do this?  Because shifting and subtraction are much more 
+	 * efficient operations than multiplication.
+	 */
+	for(int strIter = 0; strIter < length ; strIter++)
+	{
+		hashVal = aString[strIter] + (hashVal << 5) - hashVal;
+	}
+	/* we then return the hash value mod the hashtable size so that it will
+	 * fit into the necessary range
+	 */
+	return hashVal % iSize;
+
+}
+
+/** 
+Function returns ture or false based on the String availability in Hash
+
+@internalComponent
+@released
+
+@param aString - String which needs to be searched
+*/
+bool HashTable::IsAvailable(String aString)
+{
+	unsigned int hashVal = Hash(aString);
+	if (iTable[hashVal].size() > 0)
+	{
+		StringList nameList = iTable[hashVal];
+		StringList::iterator listIter = nameList.begin();
+		while(listIter != nameList.end())
+		{
+			if ((*listIter) == aString)
+			{
+				return true;
+			}
+			++listIter;
+		}
+	}
+	return false;
+}
+
+/** 
+Function responsible to insert a single string into Hash table
+
+@internalComponent
+@released
+
+@param aString - String which needs to be inserted
+*/
+void HashTable::Insert(String aString)
+{
+	unsigned int hashVal = Hash(aString);
+	if(!IsAvailable(aString)) //Is exists
+	{
+		iTable[hashVal].push_back(aString);
+	}
+}
+
+/** 
+Function responsible to insert list of strings into Hash table
+
+@internalComponent
+@released
+
+@param aString - String which needs to be inserted
+*/
+void HashTable::InsertStringList(StringList& aList)
+{
+	StringList::iterator beginIter = aList.begin();
+	StringList::iterator endIter = aList.end();
+	while(beginIter != endIter)
+	{
+		Insert((*beginIter));
+		++beginIter;
+	}
+}
+
+/** 
+Function to delete an entry from Hash
+
+@internalComponent
+@released
+
+@param aString - String which needs to be deleted
+*/
+void HashTable::Delete(String aString)
+{
+	unsigned int hashVal = Hash(aString);
+	if(iTable[hashVal].size() > 0)
+	{
+		StringList list = iTable[hashVal];
+		StringList::iterator beginIter = list.begin();
+		StringList::iterator endIter = list.end();
+		while(beginIter != endIter)
+		{
+			if((*beginIter) == aString)
+			{
+				list.erase(beginIter);
+				iTable[hashVal] = list;
+				return;
+			}
+			++beginIter;
+		}
+	}
+}