Inheritance diagram for Deveel.Data.Store.ObjectStore:

Classes
class	LargeObject

Public Member Functions
	ObjectStore (int id, IStore store)

long	Create ()

void	Open (long offset)

void	Dispose ()

ILargeObject	CreateNewObject (long maxSize, bool compressed)
	Creates a new large object returning a reference to it. More...

ILargeObject	GetObject (ObjectId id)
	Gets an object that was previously created for the given unique identifier. More...

Properties
int	Id `[get, private set]`

Properties inherited from Deveel.Data.Store.IObjectStore
int	Id `[get]`
	Gets the unique identifier of the store within a database system. More...

Private Member Functions
long	AddToRecordList (long recordOffset)

void	CompleteObject (LargeObject obj)

void	WriteObjectPart (long id, long objOffset, byte[] buffer, int off, int length)

int	ReadObjectPart (long id, long objOffset, byte[] buffer, int off, int length)

void	EstablishReference (long id)

bool	ReleaseReference (long id)

Private Attributes
const int	Magic = 0x012BC53A9

const int	DeletedFlag = 0x020000

const int	CompressedFlag = 0x010

const int	PageSize = 64

readonly IStore	store

readonly FixedRecordList	fixedList

long	firstDeleteChainRecord

Detailed Description

Definition at line 24 of file ObjectStore.cs.

Constructor & Destructor Documentation

Deveel.Data.Store.ObjectStore.ObjectStore	(	int	id,
		IStore	store
	)

inline

Definition at line 37 of file ObjectStore.cs.

                                                  {
             if (id < 0)
                 throw new ArgumentOutOfRangeException("id");
             if (store == null)
                 throw new ArgumentNullException("store");
 
             Id = id;
             this.store = store;
             fixedList = new FixedRecordList(store, 30);
         }

Member Function Documentation

long Deveel.Data.Store.ObjectStore.AddToRecordList ( long recordOffset )

inlineprivate

Definition at line 48 of file ObjectStore.cs.

                                                         {
             lock (fixedList) {
                 // If there is no free deleted records in the delete chain,
                 if (firstDeleteChainRecord == -1) {
                     // Increase the size of the list structure.
                     fixedList.IncreaseSize();
                     // The start record of the new size
                     int newBlockNumber = fixedList.BlockCount - 1;
                     long startIndex = fixedList.BlockFirstPosition(newBlockNumber);
                     long sizeOfBlock = fixedList.BlockNodeCount(newBlockNumber);
 
                     // The IArea object for the new position
                     IArea a = fixedList.GetRecord(startIndex);
 
                     a.WriteInt4(0);
                     a.WriteInt4(0);
                     a.WriteInt8(-1);  // Initially unknown size
                     a.WriteInt8(0);   // Initially unknown current size
                     a.WriteInt8(recordOffset);
                     // Set the rest of the block as deleted records
                     for (long n = 1; n < sizeOfBlock - 1; ++n) {
                         a.WriteInt4(DeletedFlag);
                         a.WriteInt4(0);
                         a.WriteInt8(-1);
                         a.WriteInt8(startIndex + n + 1);
                     }
                     // The last block is end of delete chain.
                     a.WriteInt4(DeletedFlag);
                     a.WriteInt4(0);
                     a.WriteInt8(-1);
                     a.WriteInt8(-1);
                     // Check out the changes.
                     a.Flush();
 
                     // And set the new delete chain
                     firstDeleteChainRecord = startIndex + 1;
                     fixedList.WriteDeleteHead(firstDeleteChainRecord);
 
                     // Return pointer to the record we just added.
                     return startIndex;
 
                 }
 
                 // Pull free block from the delete chain and recycle it.
                 long recycledRecord = firstDeleteChainRecord;
                 IArea block = fixedList.GetRecord(recycledRecord);
                 var recordPos = block.Position;
                 // Status of the recycled block
                 int status = block.ReadInt4();
                 if ((status & DeletedFlag) == 0)
                     throw new InvalidOperationException("Assertion failed: record is not deleted!");
 
                 // Reference count (currently unused in delete chains).
                 block.ReadInt4();
                 // The size (should be -1);
                 block.ReadInt8();
                 // The current size should be 0
                 block.ReadInt8();
                 // The pointer to the next in the chain.
                 long nextChain = block.ReadInt8();
                 firstDeleteChainRecord = nextChain;
 
                 // Update the first_delete_chain_record field in the header
                 fixedList.WriteDeleteHead(firstDeleteChainRecord);
 
                 // Update the block
                 block.Position = recordPos;
                 block.WriteInt4(0);
                 block.WriteInt4(0);
                 block.WriteInt8(-1);    // Initially unknown size
                 block.WriteInt8(0);
                 block.WriteInt8(recordOffset);
 
                 // Check out the changes
                 block.Flush();
 
                 return recycledRecord;
             }
         }

void Deveel.Data.Store.ObjectStore.CompleteObject ( LargeObject obj )

inlineprivate

Definition at line 271 of file ObjectStore.cs.

                                                      {
             // Get the blob reference id (reference to the fixed record list).
             long refId = obj.Id.Id;
 
             lock (fixedList) {
                 // Update the record in the fixed list.
                 IArea block = fixedList.GetRecord(refId);
 
                 // Record the position
                 var recordPos = block.Position;
                 // Read the information in the fixed record
                 int status = block.ReadInt4();
                 // Assert that the status is open
                 if (status != 0)
                     throw new IOException("Assertion failed: record is not open.");
 
                 int refCount = block.ReadInt4();
                 long size = block.ReadInt8();
                 long currentSize = block.ReadInt8();
                 long pageCount = block.ReadInt8();
 
                 try {
                     store.Lock();
 
                     block.Position = recordPos;
                     block.WriteInt4(1);             // Status
                     block.WriteInt4(0);             // Reference Count
                     block.WriteInt8(obj.CurrentSize);   // Final Size
                     block.WriteInt8(obj.CurrentSize);
                     block.WriteInt8(pageCount);     // Page Count
                     block.Flush();
                 } finally {
                     store.Unlock();
                 }
             }
 
             // Now the object has been finalized so change the state of the object
             obj.MarkComplete();
         }

long Deveel.Data.Store.ObjectStore.Create ( )

inline

Implements Deveel.Data.Store.IObjectStore.

Definition at line 128 of file ObjectStore.cs.

                              {
             // Init the fixed record list area.
             // The fixed list entries are formatted as follows;
             //  ( status (int), reference_count (int),
             //    blob_size (long), blob_pointer (long) )
             long fixedListOffset = fixedList.Create();
 
             // Delete chain is empty when we start
             firstDeleteChainRecord = -1;
             fixedList.WriteDeleteHead(-1);
 
             // Allocate a small header that contains the MAGIC, and the pointer to the
             // fixed list structure.
             IArea blobStoreHeader = store.CreateArea(32);
             long blobStoreId = blobStoreHeader.Id;
 
             blobStoreHeader.WriteInt4(Magic);   // Magic
             blobStoreHeader.WriteInt4(1);       // The data version
             blobStoreHeader.WriteInt8(fixedListOffset);
             blobStoreHeader.Flush();
 
             // Return the pointer to the blob store header
             return blobStoreId;
         }

ILargeObject Deveel.Data.Store.ObjectStore.CreateNewObject	(	long	maxSize,
		bool	compressed
	)

inline

Creates a new large object returning a reference to it.

Parameters

maxSize	The maximum byte size that the object will use. This is a value to provide ahead of time and that will not change.
compressed	Indicates whether the created object contents will be compressed. Compression reduces the amount of size occupied by the object, but it will also affect performances when writing and reading.

Returns: Returns an instance of ILargeObject that is used to access the object stored.

Exceptions

DataStorageException If an error occurred when creating the object.

Implements Deveel.Data.Store.IObjectStore.

Definition at line 178 of file ObjectStore.cs.

                                                                            {
             if (maxSize < 0)
                 throw new IOException("Negative object size not allowed.");
 
             try {
                 store.Lock();
 
                 // Allocate the area (plus header area) for storing the blob pages
                 long pageCount = ((maxSize - 1) / (PageSize * 1024)) + 1;
                 IArea objArea = store.CreateArea((pageCount * 8) + 32);
                 long objAreaId = objArea.Id;
 
                 var type = 2;           // Binary Type
                 if (compressed)
                     type |= CompressedFlag;
 
                 // Set up the area header
                 objArea.WriteInt4(0);           // Reserved for future
                 objArea.WriteInt4(type);
                 objArea.WriteInt8(maxSize);
                 objArea.WriteInt8(0);
                 objArea.WriteInt8(pageCount);
 
                 // Initialize the empty blob area
                 for (long i = 0; i < pageCount; ++i) {
                     objArea.WriteInt8(-1);
                 }
 
                 // And finish
                 objArea.Flush();
 
                 // Update the fixed_list and return the record number for this blob
                 long refId = AddToRecordList(objAreaId);
                 return new LargeObject(this, refId, maxSize, 0, compressed, false);
             } finally {
                 store.Unlock();
             }
         }

void Deveel.Data.Store.ObjectStore.Dispose ( )

inline

Definition at line 173 of file ObjectStore.cs.

173 {

174 }

void Deveel.Data.Store.ObjectStore.EstablishReference ( long id )

inlineprivate

Definition at line 535 of file ObjectStore.cs.

                                                  {
             try {
                 lock (fixedList) {
                     // Update the record in the fixed list.
                     IArea block = fixedList.GetRecord(id);
                     var recordPos = block.Position;
                     int status = block.ReadInt4();
                     if (status != 1)
                         throw new Exception("Assertion failed: record is not static.");
 
                     int refCount = block.ReadInt4();
 
                     // Set the fixed blob record as complete.
                     block.Position = recordPos + 4;
                     block.WriteInt4(refCount + 1);
                     block.Flush();
                 }
             } catch (IOException e) {
                 throw new Exception("IO Error: " + e.Message);
             }
         }

ILargeObject Deveel.Data.Store.ObjectStore.GetObject ( ObjectId id )

inline

Gets an object that was previously created for the given unique identifier.

Parameters

id	The unique identifier of the object to return.

Returns: Returns an instance of ILargeObject that references an object that was previously created by CreateNewObject.

Exceptions

InvalidObjectIdException If the given id is outside the range of the store.

See also: CreateNewObject

Implements Deveel.Data.Store.IObjectStore.

Definition at line 490 of file ObjectStore.cs.

                                                    {
             long objOffset;
             long maxSize;
             long currentSize;
             lock (fixedList) {
                 if (id.StoreId != Id)
                     throw new InvalidObjectIdException(id);
 
                 var refId = id.Id;
                 // Assert that the blob reference id given is a valid range
                 if (refId < 0 || refId >= fixedList.NodeCount)
                     throw new InvalidObjectIdException(id);
 
                 // Position on this record
                 IArea block = fixedList.GetRecord(refId);
                 // Read the information in the fixed record
                 int status = block.ReadInt4();
                 // Assert that the status is not deleted
                 if ((status & DeletedFlag) != 0)
                     throw new InvalidOperationException("Assertion failed: record is deleted!");
 
                 // Get the reference count
                 int refCount = block.ReadInt4();
                 // Get the total size of the blob
                 maxSize = block.ReadInt8();
                 // Get the current running size
                 currentSize = block.ReadInt8();
                 // Get the blob pointer
                 objOffset = block.ReadInt8();
             }
 
             IArea area = store.GetArea(objOffset);
             area.Position = 0;
             area.ReadInt4();  // (reserved)
             // Read the type
             int type = area.ReadInt4();
             // The size of the block
             long blockSize = area.ReadInt8();
             // The number of pages in the blob
             long pageCount = area.ReadInt8();
 
             bool compressed = (type & CompressedFlag) != 0;
             return new LargeObject(this, id.Id, maxSize, currentSize, compressed, true);
         }

void Deveel.Data.Store.ObjectStore.Open ( long offset )

inline

Implements Deveel.Data.Store.IObjectStore.

Definition at line 153 of file ObjectStore.cs.

                                       {
             // Get the header area
             IArea headerArea = store.GetArea(offset);
             headerArea.Position = 0;
 
             // Read the magic
             int magic = headerArea.ReadInt4();
             int version = headerArea.ReadInt4();
             if (magic != Magic)
                 throw new IOException("The magic value for this Object Store is not correct.");
             if (version != 1)
                 throw new IOException("The version number for this Object Store is not correct.");
 
             long fixedListOffset = headerArea.ReadInt8();
             fixedList.Open(fixedListOffset);
 
             // Set the delete chain
             firstDeleteChainRecord = fixedList.ReadDeleteHead();
         }

int Deveel.Data.Store.ObjectStore.ReadObjectPart	(	long	id,
		long	objOffset,
		byte[]	buffer,
		int	off,
		int	length
	)

inlineprivate

Definition at line 404 of file ObjectStore.cs.

                                                                                                 {
             // ASSERT: Read and Write position must be 64K aligned.
             if (off % (64 * 1024) != 0) {
                 throw new Exception("Assert failed: offset is not 64k aligned.");
             }
             // ASSERT: Length is less than or equal to 64K
             if (length > (64 * 1024)) {
                 throw new Exception("Assert failed: length is greater than 64K.");
             }
 
             int status;
             long maxSize;
             long currentSize;
             long objPointer;
 
             lock (fixedList) {
                 // Assert that the blob reference id given is a valid range
                 if (id < 0 || id >= fixedList.NodeCount) {
                     throw new IOException("Object ID is out of range.");
                 }
 
                 // Position on this record
                 IArea block = fixedList.GetRecord(id);
                 // Read the information in the fixed record
                 status = block.ReadInt4();
                 // Assert that the status is not deleted
                 if ((status & DeletedFlag) != 0)
                     throw new InvalidOperationException("Assertion failed: record is deleted!");
 
                 // Get the reference count
                 block.ReadInt4();
                 // Get the total size of the object
                 maxSize = block.ReadInt8();
                 // Get the current running size of the block
                 currentSize = block.ReadInt8();
                 // Get the blob pointer
                 objPointer = block.ReadInt8();
 
             }
 
             // Assert that the area being Read is within the bounds of the object
             if (off < 0 || objOffset + length > maxSize) {
                 throw new IOException("Invalid Read.  offset = " + objOffset + ", length = " + length + " > maxSize = " + maxSize);
             }
 
             // Open an IArea into the object
             IArea area = store.GetArea(objPointer);
             area.ReadInt4();
             int type = area.ReadInt4();
 
             // Convert to the page number
             long pageNumber = (objOffset / (64 * 1024));
             area.Position = (int)((pageNumber * 8) + 32);
             long pagePointer = area.ReadInt8();
 
             // Read the page
             IArea pageArea = store.GetArea(pagePointer);
             pageArea.Position = 0;
             int pageType = pageArea.ReadInt4();
             int pageSize = pageArea.ReadInt4();
 
             if ((type & CompressedFlag) != 0) {
 #if !PCL
                 // The page is compressed
                 byte[] pageBuf = new byte[pageSize];
                 int readCount = pageArea.Read(pageBuf, 0, pageSize);
 
                 var deflateStream = new DeflateStream(new MemoryStream(pageBuf, 0, pageSize), CompressionMode.Decompress, false);
                 try {
                     int resultLength = deflateStream.Read(buffer, off, length);
                     if (resultLength != length)
                         throw new Exception("Assert failed: decompressed length is incorrect.");
 
                     return readCount;
                 } catch(InvalidDataException e) {
                     throw new IOException("ZIP Data Format Error: " + e.Message);
                 }
 #else
                 throw new NotSupportedException("Compression not supported in PCL.");
 #endif
             }
 
             // The page is not compressed
             return pageArea.Read(buffer, off, length);
         }

bool Deveel.Data.Store.ObjectStore.ReleaseReference ( long id )

inlineprivate

Definition at line 557 of file ObjectStore.cs.

                                                {
             try {
                 lock (fixedList) {
                     // Update the record in the fixed list.
                     IArea block = fixedList.GetRecord(id);
                     var recordPos = block.Position;
                     int status = block.ReadInt4();
                     if (status != 1)
                         throw new Exception("Assertion failed: Record is not static (status = " + status + ")");
 
                     int refCount = block.ReadInt4();
                     if (refCount == 0)
                         throw new Exception("Releasing when IBlob reference counter is at 0.");
 
                     var objSize = block.ReadInt8();
                     var objPos = block.ReadInt8();
 
                     // If reference count == 0 then we need to free all the resources
                     // associated with this object in the store.
                     if ((refCount - 1) == 0) {
                         // Free the resources associated with this object.
                         IArea area = store.GetArea(objPos);
                         area.ReadInt4();
 
                         var type = (byte)area.ReadInt4();
                         var totalSize = area.ReadInt8();
                         var pageCount = area.ReadInt8();
 
                         // Free all of the pages in this blob.
                         for (long i = 0; i < pageCount; ++i) {
                             long pageOffset = area.ReadInt8();
                             if (pageOffset > 0)
                                 store.DeleteArea(pageOffset);
                         }
 
                         // Free the blob area object itself.
                         store.DeleteArea(objPos);
 
                         // Write out the blank record.
                         block.Position = recordPos;
                         block.WriteInt4(DeletedFlag);
                         block.WriteInt4(0);
                         block.WriteInt8(-1);
                         block.WriteInt8(firstDeleteChainRecord);
                         // CHeck out these changes
                         block.Flush();
                         firstDeleteChainRecord = id;
 
                         // Update the first_delete_chain_record field in the header
                         fixedList.WriteDeleteHead(firstDeleteChainRecord);
                         return true;
                     }
 
                     // Simply decrement the reference counter for this record.
                     block.Position = recordPos + 4;
                     // Write the reference count - 1
                     block.WriteInt4(refCount - 1);
                     // Check out this change
                     block.Flush();
                     return false;
                 }
             } catch (IOException e) {
                 throw new Exception("IO Error: " + e.Message);
             }
         }

void Deveel.Data.Store.ObjectStore.WriteObjectPart	(	long	id,
		long	objOffset,
		byte[]	buffer,
		int	off,
		int	length
	)

inlineprivate

Definition at line 311 of file ObjectStore.cs.

                                                                                                   {
             // ASSERT: Read and Write position must be 64K aligned.
             if (objOffset%(PageSize*1024) != 0)
                 throw new Exception("Assert failed: offset is not 64k aligned.");
 
             // ASSERT: Length is less than or equal to 64K
             if (length > (PageSize * 1024)) {
                 throw new Exception("Assert failed: length is greater than 64K.");
             }
 
             int refCount;
             long objPos;
             long maxSize;
             long currentSize;
 
             lock (fixedList) {
                 if (id < 0 || id >= fixedList.NodeCount)
                     throw new IOException("Object id is out of range.");
 
                 IArea block = fixedList.GetRecord(id);
                 var status = block.ReadInt4();
                 if ((status & DeletedFlag) != 0)
                     throw new InvalidOperationException("Assertion failed: record is deleted!");
 
                 block.ReadInt4();       // Ref count
                 maxSize = block.ReadInt8();     // Total Size / Max Size
                 currentSize = block.ReadInt8();     // Current Size
                 objPos = block.ReadInt8();  // Last Page Position
             }
 
             // Open an IArea into the blob
             IArea area = store.GetArea(objPos);
             area.ReadInt4();
             var type = area.ReadInt4();
             var size = area.ReadInt8();
 
             // Assert that the area being Read is within the bounds of the blob
             if (objOffset < 0 || objOffset + length > size) {
                 throw new IOException("Object invalid write.  offset = " + objOffset + ", length = " + length + ", size = " + size);
             }
 
             // Convert to the page number
             long pageNumber = (objOffset / (PageSize * 1024));
             area.Position = (int)((pageNumber * 8) + 32);
             long pagePos = area.ReadInt8();
 
             if (pagePos != -1) {
                 // This means we are trying to rewrite a page we've already written
                 // before.
                 throw new Exception("Assert failed: page position is not -1");
             }
 
             // Is the compression bit set?
             byte[] toWrite;
             int writeLength;
             if ((type & CompressedFlag) != 0) {
                 // Yes, compression
 #if !PCL
                 var deflateStream = new DeflateStream(new MemoryStream(buffer, off, length), CompressionMode.Compress, false);
                 toWrite = new byte[PageSize * 1024];
                 writeLength = deflateStream.Read(toWrite, 0, toWrite.Length);
 #else
                 throw new NotSupportedException("Compression not supported in PCL.");
 #endif
             } else {
                 // No compression
                 toWrite = buffer;
                 writeLength = length;
             }
 
             try {
                 store.Lock();
 
                 // Allocate and Write the page.
                 IArea pageArea = store.CreateArea(writeLength + 8);
                 pagePos = pageArea.Id;
                 pageArea.WriteInt4(1);
                 pageArea.WriteInt4(writeLength);
                 pageArea.Write(toWrite, 0, writeLength);
                 // Finish this page
                 pageArea.Flush();
 
                 // Update the page in the header.
                 area.Position = (int)((pageNumber * 8) + 24);
                 area.WriteInt8(currentSize + writeLength);
                 area.WriteInt8(pagePos);
                 // Check out this change.
                 area.Flush();
             } finally {
                 store.Unlock();
             }
         }

Member Data Documentation

const int Deveel.Data.Store.ObjectStore.CompressedFlag = 0x010

private

Definition at line 28 of file ObjectStore.cs.

const int Deveel.Data.Store.ObjectStore.DeletedFlag = 0x020000

private

Definition at line 27 of file ObjectStore.cs.

long Deveel.Data.Store.ObjectStore.firstDeleteChainRecord

private

Definition at line 35 of file ObjectStore.cs.

readonly FixedRecordList Deveel.Data.Store.ObjectStore.fixedList

private

Definition at line 33 of file ObjectStore.cs.

const int Deveel.Data.Store.ObjectStore.Magic = 0x012BC53A9

private

Definition at line 25 of file ObjectStore.cs.

const int Deveel.Data.Store.ObjectStore.PageSize = 64

private

Definition at line 30 of file ObjectStore.cs.

readonly IStore Deveel.Data.Store.ObjectStore.store

private

Definition at line 32 of file ObjectStore.cs.

Property Documentation

int Deveel.Data.Store.ObjectStore.Id

getprivate set

Definition at line 176 of file ObjectStore.cs.

The documentation for this class was generated from the following file:

/var/calculate/remote/distfiles/egit-src/deveeldb.git/src/deveeldb/Deveel.Data.Store/ObjectStore.cs

Classes

Public Member Functions

Properties

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

Property Documentation