Class DataStreamUnsafeUtility

DataStream (Reader/Writer) unsafe utilities used to do pointer operations on streams.

These are added to the DataStreamWriter/DataStreamReader classes as extensions, so you need to add using Unity.Collections.LowLevel.Unsafe at the top of file where you need to access these functions.

Since these are unsafe C# operations care must be taken when using them, it can easily crash the editor/player.

Every time data is written directly to the data stream buffer you must call WriteBytesWithUnsafePointer afterwards with the length of the data written so that the stream class can internally keep track of how much of the internal buffer has been written to.

The functions have read/write access check variants which utilize the job system atomic safety handle. The ENABLE_UNITY_COLLECTIONS_CHECKS define needs to be used for this to work. For more information see Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.

Example of typical usage:

// Manually write some numbers into a data stream from a source buffer.
var data = new DataStreamWriter(4, Allocator.Temp);
unsafe
{
    var ptr = data.GetUnsafePtr();
    var sourceData = new NativeArray<byte>(4, Allocator.Temp);
    sourceData[0] = 42;
    sourceData[1] = 42;
    sourceData[2] = 42;
    sourceData[3] = 42;
    UnsafeUtility.MemCpy(ptr, sourceData.GetUnsafePtr(), sourceData.Length);
    data.WriteBytesWithUnsafePointer(sourceData.Length);
}

Inheritance

Object

DataStreamUnsafeUtility

Namespace: Unity.Networking.Transport.LowLevel.Unsafe

Syntax

public static class DataStreamUnsafeUtility

Methods

CreateReaderFromExistingData(Byte*, Int32)

Declaration

public static DataStreamReader CreateReaderFromExistingData(byte *data, int length)

Parameters

Type	Name	Description
Byte*	data
Int32	length

Returns

Type	Description
DataStreamReader

GetUnsafeBufferPointerWithoutChecks(DataStreamWriter)

Get the byte* pointer to the buffer backing the DataStreamWriter. Does not check the safety handle for read/write access.

Declaration

public static byte *GetUnsafeBufferPointerWithoutChecks(this DataStreamWriter strm)

Parameters

Type	Name	Description
DataStreamWriter	strm

Returns

Type	Description
Byte*	Pointer to the data stream buffer.

GetUnsafePtr(DataStreamWriter)

Get the byte* pointer to the start of the buffer backing the DataStreamWriter. A safety check is done to see if you have write access to the buffer.

Declaration

public static byte *GetUnsafePtr(this DataStreamWriter strm)

Parameters

Type	Name	Description
DataStreamWriter	strm

Returns

Type	Description
Byte*	Pointer to the data stream buffer.

GetUnsafeReadOnlyPtr(DataStreamReader)

Get the byte* pointer to the start of the buffer backing the DataStreamReader. A safety check is done to make sure you only have read access to the buffer.

Declaration

public static byte *GetUnsafeReadOnlyPtr(this DataStreamReader strm)

Parameters

Type	Name	Description
DataStreamReader	strm

Returns

Type	Description
Byte*	Pointer to the data stream buffer.

GetUnsafeReadOnlyPtr(DataStreamWriter)

Get the byte* pointer to the start of the buffer backing the DataStreamWriter. A safety check is done to make sure you only have read access to the buffer.

Declaration

public static byte *GetUnsafeReadOnlyPtr(this DataStreamWriter strm)

Parameters

Type	Name	Description
DataStreamWriter	strm

Returns

Type	Description
Byte*	Pointer to the data stream buffer.

WriteBytesWithUnsafePointer(DataStreamWriter, Int32)

Signal how many bytes have been written to the buffer used by the data stream using one of the unsafe pointer getters.

Declaration

public static void WriteBytesWithUnsafePointer(this DataStreamWriter strm, int length)

Parameters

Type	Name	Description
DataStreamWriter	strm
Int32	length	Amount of data written to the buffer.

Exceptions

Type	Condition
ArgumentOutOfRangeException	If the length specified brings the total length to a value higher than the capacity of the buffer.