ReadFileScatterAsync()

static unsafe ValueTask< int > System.IO.RandomAccess.ReadFileScatterAsync ( SafeFileHandle handle, IntPtr segmentsPtr, int bytesToRead, long fileOffset, CancellationToken cancellationToken )

inlinestaticprivate

Definition at line 623 of file RandomAccess.cs.

    {
        handle.EnsureThreadPoolBindingInitialized();
        SafeFileHandle.OverlappedValueTaskSource overlappedValueTaskSource = handle.GetOverlappedValueTaskSource();
        try
        {
            NativeOverlapped* ptr = overlappedValueTaskSource.PrepareForOperation(Memory<byte>.Empty, fileOffset);
            if (Interop.Kernel32.ReadFileScatter(handle, (long*)(void*)segmentsPtr, bytesToRead, IntPtr.Zero, ptr) == 0)
            {
                int lastWin32ErrorAndDisposeHandleIfInvalid = FileStreamHelpers.GetLastWin32ErrorAndDisposeHandleIfInvalid(handle);
                switch (lastWin32ErrorAndDisposeHandleIfInvalid)
                {
                case 997:
                    overlappedValueTaskSource.RegisterForCancellation(cancellationToken);
                    break;
                case 38:
                case 109:
                    ptr->InternalLow = IntPtr.Zero;
                    overlappedValueTaskSource.Dispose();
                    return ValueTask.FromResult(0);
                default:
                    overlappedValueTaskSource.Dispose();
                    return ValueTask.FromException<int>(Win32Marshal.GetExceptionForWin32Error(lastWin32ErrorAndDisposeHandleIfInvalid, handle.Path));
                }
            }
        }
        catch
        {
            overlappedValueTaskSource.Dispose();
            throw;
        }
        overlappedValueTaskSource.FinishedScheduling();
        return new ValueTask<int>(overlappedValueTaskSource, overlappedValueTaskSource.Version);
    }

References System.IO.RandomAccess.cancellationToken, System.IO.RandomAccess.fileOffset, System.Threading.Tasks.ValueTask< TResult >.FromException(), System.IO.Win32Marshal.GetExceptionForWin32Error(), System.IO.Strategies.FileStreamHelpers.GetLastWin32ErrorAndDisposeHandleIfInvalid(), System.handle, Interop.Kernel32.ReadFileScatter(), and System.IntPtr.Zero.

Referenced by System.IO.RandomAccess.ReadScatterAtOffsetSingleSyscallAsync().