/// <summary>
/// Initializes growable buffer.
/// </summary>
/// <param name="buffer">Pre-allocated buffer used by this builder.</param>
/// <param name="allocator">The memory allocator used to rent the memory blocks.</param>
/// <remarks>
/// The builder created with this constructor is growable. However, additional memory will not be
/// requested using <paramref name="allocator"/> while <paramref name="buffer"/> space is sufficient.
/// If <paramref name="allocator"/> is <see langword="null"/> then <see cref="ArrayPool{T}.Shared"/>
/// is used for memory pooling.
/// </remarks>
public BufferWriterSlim(Span <T> buffer, MemoryAllocator <T>?allocator = null)
{
initialBuffer = buffer;
this.allocator = allocator;
extraBuffer = default;
position = 0;
}
protected override void Dispose(bool disposing)
{
owner.Dispose();
owner = default;
writtenCount = 0;
base.Dispose(disposing);
}
/// <summary>
/// Clears the data written to the underlying buffer.
/// </summary>
/// <exception cref="ObjectDisposedException">This writer has been disposed.</exception>
public override void Clear()
{
ThrowIfDisposed();
buffer.Dispose();
buffer = default;
position = 0;
}
public static void RentFromMemoryPool2()
{
using var owner = new MemoryOwner <byte>(MemoryPool <byte> .Shared.Rent, 10);
Equal(10, owner.Memory.Length);
owner[1] = 42;
Equal(42, owner[1]);
}
/// <inheritdoc/>
private protected override void Resize(int newSize)
{
var newBuffer = allocator.Invoke(newSize, false);
buffer.Memory.CopyTo(newBuffer.Memory);
buffer.Dispose();
buffer = newBuffer;
}
/// <summary>
/// Initializes growable builder.
/// </summary>
/// <param name="buffer">Pre-allocated buffer used by this builder.</param>
/// <param name="copyOnOverflow">
/// <see langword="true"/> to copy pre-allocated buffer to pooled memory on overflow;
/// <see langword="false"/> to keep head of the written content in the pre-allocated buffer.
/// </param>
/// <param name="allocator">The memory allocator used to rent the memory blocks.</param>
/// <remarks>
/// The builder created with this constructor is growable. However, additional memory will not be
/// requested using <paramref name="allocator"/> while <paramref name="buffer"/> space is sufficient.
/// If <paramref name="allocator"/> is <see langword="null"/> then <see cref="ArrayPool{T}.Shared"/>
/// is used for memory pooling.
/// <see cref="WrittenSpan"/> property is supported only if <paramref name="copyOnOverflow"/> is <see langword="true"/>.
/// Otherwise, it's not possible to represent written content as contiguous memory block.
/// </remarks>
public BufferWriterSlim(Span <T> buffer, bool copyOnOverflow, MemoryAllocator <T>?allocator = null)
{
initialBuffer = buffer;
this.allocator = allocator;
extraBuffer = default;
position = 0;
this.copyOnOverflow = copyOnOverflow;
}
public static void WrapArray()
{
var array = new byte[42];
using var owner = new MemoryOwner <byte>(array);
Equal(42, owner.Memory.Length);
owner[2] = 10;
Equal(10, array[2]);
}
/// <inheritdoc/>
private protected override void Resize(int newSize)
{
var newBuffer = allocator.Invoke(newSize, false);
buffer.Memory.CopyTo(newBuffer.Memory);
buffer.Dispose();
buffer = newBuffer;
AllocationCounter?.WriteMetric(newBuffer.Length);
}
/// <summary>
/// Initializes a new writer with the specified initial capacity.
/// </summary>
/// <param name="allocator">The allocator of internal buffer.</param>
/// <param name="initialCapacity">The initial capacity of the writer.</param>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="initialCapacity"/> is less than or equal to zero.</exception>
public PooledBufferWriter(MemoryAllocator <T>?allocator, int initialCapacity)
{
if (initialCapacity <= 0)
{
throw new ArgumentOutOfRangeException(nameof(initialCapacity));
}
this.allocator = allocator;
buffer = allocator.Invoke(initialCapacity, false);
}
/// <summary>
/// Allocates memory.
/// </summary>
/// <param name="allocator">The memory allocator.</param>
/// <param name="length">The number of items in the rented memory.</param>
/// <param name="exactSize">
/// <see langword="true"/> to ask allocator to allocate exactly <paramref name="length"/>;
/// <see langword="false"/> to allocate at least <paramref name="length"/>.
/// </param>
/// <typeparam name="T">The type of the items in the memory pool.</typeparam>
/// <returns>The allocated memory.</returns>
public static MemoryOwner <T> Invoke <T>(this MemoryAllocator <T> allocator, int length, bool exactSize)
{
var result = allocator(length);
if (!exactSize)
{
MemoryOwner <T> .Expand(ref result);
}
return(result);
}
/// <inheritdoc/>
protected override void Dispose(bool disposing)
{
if (disposing)
{
buffer.Dispose();
buffer = default;
}
base.Dispose(disposing);
}
/// <inheritdoc/>
protected override void Dispose(bool disposing)
{
if (disposing)
{
BufferSizeCallback?.Invoke(buffer.Length);
buffer.Dispose();
buffer = default;
}
base.Dispose(disposing);
}
public override void Clear() => Clear(false); // TODO: Remove this method in future
/// <summary>
/// Clears the data written to the underlying memory.
/// </summary>
/// <param name="reuseBuffer"><see langword="true"/> to reuse the internal buffer; <see langword="false"/> to destroy the internal buffer.</param>
/// <exception cref="ObjectDisposedException">This writer has been disposed.</exception>
public override void Clear(bool reuseBuffer)
{
ThrowIfDisposed();
if (!reuseBuffer)
{
buffer.Dispose();
buffer = default;
}
position = 0;
}
public static void RawReference()
{
var owner = new MemoryOwner <byte>(Array.Empty <byte>());
True(Unsafe.IsNullRef(ref BufferHelpers.GetReference(in owner)));
owner = default;
True(Unsafe.IsNullRef(ref BufferHelpers.GetReference(in owner)));
owner = new(new byte[] { 10 });
Equal(10, BufferHelpers.GetReference(in owner));
}
/// <summary>
/// Initializes growable buffer.
/// </summary>
/// <param name="initialCapacity">The initial capacity of the internal buffer.</param>
/// <param name="allocator">The memory allocator used to rent the memory blocks.</param>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="initialCapacity"/> is less than zero.</exception>
public BufferWriterSlim(int initialCapacity, MemoryAllocator <T>?allocator = null)
{
if (initialCapacity < 0)
{
throw new ArgumentOutOfRangeException(nameof(initialCapacity));
}
initialBuffer = default;
this.allocator = allocator;
extraBuffer = initialCapacity == 0 ? default : allocator.Invoke(initialCapacity, false);
position = 0;
}
public static void SetBufferLength()
{
var buffer = default(MemoryOwner <byte>);
True(buffer.TryResize(0));
False(buffer.TryResize(10));
Throws <ArgumentOutOfRangeException>(() => buffer.TryResize(-1));
buffer = new MemoryOwner <byte>(new byte[] { 10, 20, 30 });
True(buffer.TryResize(1));
True(buffer.TryResize(3));
False(buffer.TryResize(10));
}
/// <summary>
/// Detaches the underlying buffer with written content from this writer.
/// </summary>
/// <param name="owner">The buffer owner.</param>
/// <returns>
/// <see langword="true"/> if the written content is in rented buffer because initial buffer overflows;
/// <see langword="false"/> if the written content is in preallocated buffer.
/// </returns>
public bool TryDetachBuffer(out MemoryOwner <T> owner)
{
if (NoOverflow)
{
owner = default;
return(false);
}
owner = extraBuffer;
owner.Truncate(position);
position = 0;
extraBuffer = default;
return(true);
}
/// <summary>
/// lears the data written to the underlying buffer.
/// </summary>
/// <param name="reuseBuffer"><see langword="true"/> to reuse the internal buffer; <see langword="false"/> to destroy the internal buffer.</param>
public void Clear(bool reuseBuffer)
{
initialBuffer.Clear();
if (!reuseBuffer)
{
extraBuffer.Dispose();
extraBuffer = default;
}
else if (RuntimeHelpers.IsReferenceOrContainsReferences <T>())
{
extraBuffer.Memory.Span.Clear();
}
position = 0;
}
public override void Clear() => Clear(false); // TODO: Remove this method in future
/// <summary>
/// Clears the data written to the underlying memory.
/// </summary>
/// <param name="reuseBuffer"><see langword="true"/> to reuse the internal buffer; <see langword="false"/> to destroy the internal buffer.</param>
/// <exception cref="ObjectDisposedException">This writer has been disposed.</exception>
public override void Clear(bool reuseBuffer)
{
ThrowIfDisposed();
if (!reuseBuffer)
{
buffer.Dispose();
buffer = default;
}
else if (RuntimeHelpers.IsReferenceOrContainsReferences <T>())
{
buffer.Memory.Span.Clear();
}
position = 0;
}
/// <summary>
/// Returns the memory to write to that is at least the requested size.
/// </summary>
/// <param name="sizeHint">The minimum length of the returned memory.</param>
/// <returns>The memory block of at least the size <paramref name="sizeHint"/>.</returns>
/// <exception cref="OutOfMemoryException">The requested buffer size is not available.</exception>
public Span <T> GetSpan(int sizeHint = 0)
{
if (sizeHint < 0)
{
throw new ArgumentOutOfRangeException(nameof(sizeHint));
}
Span <T> result;
int? newSize;
if (extraBuffer.IsEmpty)
{
newSize = IGrowableBuffer <T> .GetBufferSize(sizeHint, initialBuffer.Length, position);
// need to copy initial buffer
if (newSize.HasValue)
{
extraBuffer = allocator.Invoke(newSize.GetValueOrDefault(), false);
initialBuffer.CopyTo(extraBuffer.Memory.Span);
initialBuffer.Clear();
result = extraBuffer.Memory.Span;
}
else
{
result = initialBuffer;
}
}
else
{
newSize = IGrowableBuffer <T> .GetBufferSize(sizeHint, extraBuffer.Length, position);
// no need to copy initial buffer
if (newSize.HasValue)
{
var newBuffer = allocator.Invoke(newSize.GetValueOrDefault(), false);
extraBuffer.Memory.CopyTo(newBuffer.Memory);
extraBuffer.Dispose();
extraBuffer = newBuffer;
}
result = extraBuffer.Memory.Span;
}
return(result.Slice(position));
}
public Memory <byte> GetMemory(int sizeHint)
{
if (sizeHint < 0)
{
throw new ArgumentOutOfRangeException(nameof(sizeHint));
}
if (sizeHint == 0)
{
sizeHint = 1;
}
if (sizeHint > buffer.Length - position)
{
buffer.Dispose();
buffer = allocator(sizeHint);
}
return(buffer.Memory.Slice(position));
}
public static MemoryOwner <T> Invoke <T>(this MemoryAllocator <T>?allocator, int length, bool exactSize)
{
MemoryOwner <T> result;
if (allocator is null)
{
result = new MemoryOwner <T>(ArrayPool <T> .Shared, length, exactSize);
goto exit;
}
result = allocator(length);
if (!exactSize)
{
result.Expand();
}
exit:
return(result);
}
/// <inheritdoc />
public override MemoryOwner <T> DetachBuffer()
{
ThrowIfDisposed();
MemoryOwner <T> result;
if (position > 0)
{
result = buffer;
buffer = default;
result.Truncate(position);
position = 0;
}
else
{
result = default;
}
return(result);
}
public void Advance(int count)
{
if (count < 0)
{
throw new ArgumentOutOfRangeException(nameof(count));
}
if (position > buffer.Length - count)
{
throw new InvalidOperationException();
}
output.Write(buffer.Memory.Span.Slice(position, count));
position += count;
// release buffer if it is cannot be reused
if (position == buffer.Length)
{
buffer.Dispose();
buffer = default;
position = 0;
}
}
/// <summary>
/// Writes elements to this buffer.
/// </summary>
/// <param name="input">The span of elements to be written.</param>
/// <exception cref="InsufficientMemoryException">Pre-allocated initial buffer size is not enough to place <paramref name="input"/> elements to it and this builder is not growable.</exception>
/// <exception cref="OverflowException">The size of the internal buffer becomes greater than <see cref="int.MaxValue"/>.</exception>
public void Write(ReadOnlySpan <T> input)
{
var newSize = checked (position + input.Length);
Span <T> output;
int offset;
MemoryOwner <T> newBuffer;
if (copyOnOverflow)
{
// grow if needed
if (newSize > initialBuffer.Length)
{
if (extraBuffer.IsEmpty)
{
extraBuffer = allocator.Invoke(newSize, false);
initialBuffer.CopyTo(extraBuffer.Memory.Span);
initialBuffer.Clear();
}
else if (newSize > extraBuffer.Length)
{
newBuffer = allocator.Invoke(newSize, false);
extraBuffer.Memory.CopyTo(newBuffer.Memory);
extraBuffer.Dispose();
extraBuffer = newBuffer;
}
output = extraBuffer.Memory.Span;
}
else
{
output = initialBuffer;
}
offset = position;
}
else
{
// grow if needed
if (newSize > initialBuffer.Length && newSize - initialBuffer.Length > extraBuffer.Length)
{
newBuffer = allocator.Invoke(newSize, false);
extraBuffer.Memory.CopyTo(newBuffer.Memory);
extraBuffer.Dispose();
extraBuffer = newBuffer;
}
// append elements
if (position < initialBuffer.Length)
{
var writtenCount = Math.Min(initialBuffer.Length - position, input.Length);
input.Slice(0, writtenCount).CopyTo(initialBuffer.Slice(position));
input = input.Slice(writtenCount);
offset = 0;
}
else
{
offset = position - initialBuffer.Length;
}
output = extraBuffer.Memory.Span;
}
input.CopyTo(output.Slice(offset));
position = newSize;
}
internal PooledMemoryChunk(MemoryAllocator <T>?allocator, int length, MemoryChunk?previous = null)
: base(previous)
{
owner = allocator.Invoke(length, false);
}
internal void Realloc(MemoryAllocator <T>?allocator, int length)
{
owner.Dispose();
owner = allocator.Invoke(length, false);
}
public static void DefaultValue()
{
using var owner = new MemoryOwner <decimal>();
True(owner.IsEmpty);
True(owner.Memory.IsEmpty);
}
public static void RentFromMemoryPoolDefaultSize()
{
using var owner = new MemoryOwner <byte>(MemoryPool <byte> .Shared);
False(owner.Memory.IsEmpty);
}
internal static void Expand(ref MemoryOwner <T> owner) => Unsafe.AsRef(in owner.length) = owner.RealLength;
