/// <summary>
/// Creates a new instance of the memory block class, with a existing backing storage.
/// </summary>
/// <param name="size">Size of the memory block in bytes</param>
/// <param name="sharedMemory">Shared memory to use as backing storage for this block</param>
/// <exception cref="OutOfMemoryException">Throw when there's no enough address space left to map the shared memory</exception>
/// <exception cref="PlatformNotSupportedException">Throw when the current platform is not supported</exception>
private MemoryBlock(ulong size, IntPtr sharedMemory)
{
_pointer = MemoryManagement.MapSharedMemory(sharedMemory, size);
Size = size;
_usesSharedMemory = true;
_isMirror = true;
}
/// <summary>
/// Creates a new instance of the memory block class.
/// </summary>
/// <param name="size">Size of the memory block in bytes</param>
/// <param name="flags">Flags that controls memory block memory allocation</param>
/// <exception cref="OutOfMemoryException">Throw when there's no enough memory to allocate the requested size</exception>
/// <exception cref="PlatformNotSupportedException">Throw when the current platform is not supported</exception>
public MemoryBlock(ulong size, MemoryAllocationFlags flags = MemoryAllocationFlags.None)
{
if (flags.HasFlag(MemoryAllocationFlags.Mirrorable))
{
_sharedMemory = MemoryManagement.CreateSharedMemory(size, flags.HasFlag(MemoryAllocationFlags.Reserve));
_pointer = MemoryManagement.MapSharedMemory(_sharedMemory, size);
_usesSharedMemory = true;
}
else if (flags.HasFlag(MemoryAllocationFlags.Reserve))
{
_viewCompatible = flags.HasFlag(MemoryAllocationFlags.ViewCompatible);
_forceWindows4KBView = flags.HasFlag(MemoryAllocationFlags.ForceWindows4KBViewMapping);
_pointer = MemoryManagement.Reserve(size, _viewCompatible);
}
else
{
_pointer = MemoryManagement.Allocate(size);
}
Size = size;
_viewStorages = new ConcurrentDictionary <MemoryBlock, byte>();
_viewStorages.TryAdd(this, 0);
_viewCount = 1;
}
/// <summary>
/// Decrements the number of views that uses this memory block as storage.
/// </summary>
private void DecrementViewCount()
{
if (Interlocked.Decrement(ref _viewCount) == 0 && _sharedMemory != IntPtr.Zero && !_isMirror)
{
MemoryManagement.DestroySharedMemory(_sharedMemory);
_sharedMemory = IntPtr.Zero;
}
}
private void FreeMemory()
{
IntPtr ptr = Interlocked.Exchange(ref _pointer, IntPtr.Zero);
// If pointer is null, the memory was already freed or never allocated.
if (ptr != IntPtr.Zero)
{
MemoryManagement.Free(ptr);
}
}
protected override void DisposeUnmanaged()
{
IntPtr ptr = Interlocked.Exchange(ref _pointer, IntPtr.Zero);
// If pointer is null, the memory was already freed or never allocated.
if (ptr != IntPtr.Zero)
{
MemoryManagement.Free(ptr);
}
}
/// <summary>
/// Initializes a new instance of the memory block class.
/// </summary>
/// <param name="size">Size of the memory block</param>
/// <param name="flags">Flags that controls memory block memory allocation</param>
/// <exception cref="OutOfMemoryException">Throw when there's no enough memory to allocate the requested size</exception>
/// <exception cref="PlatformNotSupportedException">Throw when the current platform is not supported</exception>
public MemoryBlock(ulong size, MemoryAllocationFlags flags = MemoryAllocationFlags.None)
{
if (flags.HasFlag(MemoryAllocationFlags.Reserve))
{
_pointer = MemoryManagement.Reserve(size);
}
else
{
_pointer = MemoryManagement.Allocate(size);
}
Size = size;
}
/// <summary>
/// Maps a view of memory from another memory block.
/// </summary>
/// <param name="srcBlock">Memory block from where the backing memory will be taken</param>
/// <param name="srcOffset">Offset on <paramref name="srcBlock"/> of the region that should be mapped</param>
/// <param name="dstOffset">Offset to map the view into on this block</param>
/// <param name="size">Size of the range to be mapped</param>
/// <exception cref="NotSupportedException">Throw when the source memory block does not support mirroring</exception>
/// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
/// <exception cref="InvalidMemoryRegionException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
public void MapView(MemoryBlock srcBlock, ulong srcOffset, ulong dstOffset, ulong size)
{
if (srcBlock._sharedMemory == IntPtr.Zero)
{
throw new ArgumentException("The source memory block is not mirrorable, and thus cannot be mapped on the current block.");
}
if (_viewStorages.TryAdd(srcBlock, 0))
{
srcBlock.IncrementViewCount();
}
MemoryManagement.MapView(srcBlock._sharedMemory, srcOffset, GetPointerInternal(dstOffset, size), size, _forceWindows4KBView);
}
/// <summary>
/// Creates a new instance of the memory block class.
/// </summary>
/// <param name="size">Size of the memory block in bytes</param>
/// <param name="flags">Flags that controls memory block memory allocation</param>
/// <exception cref="OutOfMemoryException">Throw when there's no enough memory to allocate the requested size</exception>
/// <exception cref="PlatformNotSupportedException">Throw when the current platform is not supported</exception>
public MemoryBlock(ulong size, MemoryAllocationFlags flags = MemoryAllocationFlags.None)
{
if (flags.HasFlag(MemoryAllocationFlags.Mirrorable))
{
_sharedMemory = MemoryManagement.CreateSharedMemory(size, flags.HasFlag(MemoryAllocationFlags.Reserve));
_pointer = MemoryManagement.MapSharedMemory(_sharedMemory);
_usesSharedMemory = true;
}
else if (flags.HasFlag(MemoryAllocationFlags.Reserve))
{
_pointer = MemoryManagement.Reserve(size);
}
else
{
_pointer = MemoryManagement.Allocate(size);
}
Size = size;
}
private void FreeMemory()
{
IntPtr ptr = Interlocked.Exchange(ref _pointer, IntPtr.Zero);
// If pointer is null, the memory was already freed or never allocated.
if (ptr != IntPtr.Zero)
{
if (_usesSharedMemory)
{
MemoryManagement.UnmapSharedMemory(ptr);
if (_sharedMemory != IntPtr.Zero && !_isMirror)
{
MemoryManagement.DestroySharedMemory(_sharedMemory);
_sharedMemory = IntPtr.Zero;
}
}
else
{
MemoryManagement.Free(ptr);
}
}
}
private void FreeMemory()
{
IntPtr ptr = Interlocked.Exchange(ref _pointer, IntPtr.Zero);
// If pointer is null, the memory was already freed or never allocated.
if (ptr != IntPtr.Zero)
{
if (_usesSharedMemory)
{
MemoryManagement.UnmapSharedMemory(ptr, Size);
}
else
{
MemoryManagement.Free(ptr);
}
foreach (MemoryBlock viewStorage in _viewStorages.Keys)
{
viewStorage.DecrementViewCount();
}
_viewStorages.Clear();
}
}
/// <summary>
/// Reprotects a region of memory.
/// </summary>
/// <param name="offset">Starting offset of the range to be reprotected</param>
/// <param name="size">Size of the range to be reprotected</param>
/// <param name="permission">New memory permissions</param>
/// <param name="throwOnFail">True if a failed reprotect should throw</param>
/// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
/// <exception cref="InvalidMemoryRegionException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
/// <exception cref="MemoryProtectionException">Throw when <paramref name="permission"/> is invalid</exception>
public void Reprotect(ulong offset, ulong size, MemoryPermission permission, bool throwOnFail = true)
{
MemoryManagement.Reprotect(GetPointerInternal(offset, size), size, permission, _viewCompatible, _forceWindows4KBView, throwOnFail);
}
/// <summary>
/// Unmaps a view of memory from another memory block.
/// </summary>
/// <param name="srcBlock">Memory block from where the backing memory was taken during map</param>
/// <param name="offset">Offset of the view previously mapped with <see cref="MapView"/></param>
/// <param name="size">Size of the range to be unmapped</param>
public void UnmapView(MemoryBlock srcBlock, ulong offset, ulong size)
{
MemoryManagement.UnmapView(srcBlock._sharedMemory, GetPointerInternal(offset, size), size, _forceWindows4KBView);
}
/// <summary>
/// Decommits a region of memory that has previously been reserved and optionally comitted.
/// This can be used to free previously allocated memory on demand.
/// </summary>
/// <param name="offset">Starting offset of the range to be decommitted</param>
/// <param name="size">Size of the range to be decommitted</param>
/// <returns>True if the operation was successful, false otherwise</returns>
/// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
/// <exception cref="InvalidMemoryRegionException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
public bool Decommit(ulong offset, ulong size)
{
return(MemoryManagement.Decommit(GetPointerInternal(offset, size), size));
}
/// <summary>
/// Reprotects a region of memory.
/// </summary>
/// <param name="offset">Starting offset of the range to be reprotected</param>
/// <param name="size">Size of the range to be reprotected</param>
/// <param name="permission">New memory permissions</param>
/// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
/// <exception cref="InvalidMemoryRegionException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
/// <exception cref="MemoryProtectionException">Throw when <paramref name="permission"/> is invalid</exception>
public void Reprotect(ulong offset, ulong size, MemoryPermission permission)
{
MemoryManagement.Reprotect(GetPointerInternal(offset, size), size, permission);
}
/// <summary>
/// Remaps a region of memory into this memory block.
/// </summary>
/// <param name="offset">Starting offset of the range to be remapped into</param>
/// <param name="sourceAddress">Starting offset of the range to be remapped from</param>
/// <param name="size">Size of the range to be remapped</param>
/// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
/// <exception cref="InvalidMemoryRegionException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
/// <exception cref="MemoryProtectionException">Throw when <paramref name="permission"/> is invalid</exception>
public void Remap(ulong offset, IntPtr sourceAddress, ulong size)
{
MemoryManagement.Remap(GetPointerInternal(offset, size), sourceAddress, size);
}
/// <summary>
/// Reprotects a region of memory.
/// </summary>
/// <param name="offset">Starting offset of the range to be reprotected</param>
/// <param name="size">Size of the range to be reprotected</param>
/// <param name="permission">New memory permissions</param>
/// <param name="throwOnFail">True if a failed reprotect should throw</param>
/// <exception cref="ObjectDisposedException">Throw when the memory block has already been disposed</exception>
/// <exception cref="InvalidMemoryRegionException">Throw when either <paramref name="offset"/> or <paramref name="size"/> are out of range</exception>
/// <exception cref="MemoryProtectionException">Throw when <paramref name="permission"/> is invalid</exception>
public void Reprotect(ulong offset, ulong size, MemoryPermission permission, bool throwOnFail = true)
{
MemoryManagement.Reprotect(GetPointerInternal(offset, size), size, permission, throwOnFail);
}
