internal static MemoryMappedView CreateView(SafeMemoryMappedFileHandle memMappedFileHandle, MemoryMappedFileAccess access, long offset, long size)
{
ulong num3;
ulong num = (ulong)(offset % ((long)MemoryMappedFile.GetSystemPageAllocationGranularity()));
ulong num2 = ((ulong)offset) - num;
if (size != 0L)
{
num3 = ((ulong)size) + num;
}
else
{
num3 = 0L;
}
if ((IntPtr.Size == 4) && (num3 > 0xffffffffL))
{
throw new ArgumentOutOfRangeException("size", System.SR.GetString("ArgumentOutOfRange_CapacityLargerThanLogicalAddressSpaceNotAllowed"));
}
Microsoft.Win32.UnsafeNativeMethods.MEMORYSTATUSEX lpBuffer = new Microsoft.Win32.UnsafeNativeMethods.MEMORYSTATUSEX();
Microsoft.Win32.UnsafeNativeMethods.GlobalMemoryStatusEx(lpBuffer);
ulong ullTotalVirtual = lpBuffer.ullTotalVirtual;
if (num3 >= ullTotalVirtual)
{
throw new IOException(System.SR.GetString("IO_NotEnoughMemory"));
}
uint dwFileOffsetLow = (uint)(num2 & 0xffffffffL);
uint dwFileOffsetHigh = (uint)(num2 >> 0x20);
SafeMemoryMappedViewHandle address = Microsoft.Win32.UnsafeNativeMethods.MapViewOfFile(memMappedFileHandle, MemoryMappedFile.GetFileMapAccess(access), dwFileOffsetHigh, dwFileOffsetLow, new UIntPtr(num3));
if (address.IsInvalid)
{
System.IO.__Error.WinIOError(Marshal.GetLastWin32Error(), string.Empty);
}
Microsoft.Win32.UnsafeNativeMethods.MEMORY_BASIC_INFORMATION buffer = new Microsoft.Win32.UnsafeNativeMethods.MEMORY_BASIC_INFORMATION();
Microsoft.Win32.UnsafeNativeMethods.VirtualQuery(address, ref buffer, (IntPtr)Marshal.SizeOf(buffer));
ulong regionSize = (ulong)buffer.RegionSize;
if ((buffer.State & 0x2000) != 0)
{
Microsoft.Win32.UnsafeNativeMethods.VirtualAlloc(address, (UIntPtr)regionSize, 0x1000, MemoryMappedFile.GetPageAccess(access));
int errorCode = Marshal.GetLastWin32Error();
if (address.IsInvalid)
{
System.IO.__Error.WinIOError(errorCode, string.Empty);
}
}
if (size == 0L)
{
size = (long)(regionSize - num);
}
address.Initialize(((ulong)size) + num);
return(new MemoryMappedView(address, (long)num, size, access));
}
internal static MemoryMappedView CreateView(SafeMemoryMappedFileHandle memMappedFileHandle, MemoryMappedFileAccess access, long offset, long size)
{
ulong num3;
ulong num = (ulong) (offset % ((long) MemoryMappedFile.GetSystemPageAllocationGranularity()));
ulong num2 = ((ulong) offset) - num;
if (size != 0L)
{
num3 = ((ulong) size) + num;
}
else
{
num3 = 0L;
}
if ((IntPtr.Size == 4) && (num3 > 0xffffffffL))
{
throw new ArgumentOutOfRangeException("size", System.SR.GetString("ArgumentOutOfRange_CapacityLargerThanLogicalAddressSpaceNotAllowed"));
}
Microsoft.Win32.UnsafeNativeMethods.MEMORYSTATUSEX lpBuffer = new Microsoft.Win32.UnsafeNativeMethods.MEMORYSTATUSEX();
Microsoft.Win32.UnsafeNativeMethods.GlobalMemoryStatusEx(lpBuffer);
ulong ullTotalVirtual = lpBuffer.ullTotalVirtual;
if (num3 >= ullTotalVirtual)
{
throw new IOException(System.SR.GetString("IO_NotEnoughMemory"));
}
uint dwFileOffsetLow = (uint) (num2 & 0xffffffffL);
uint dwFileOffsetHigh = (uint) (num2 >> 0x20);
SafeMemoryMappedViewHandle address = Microsoft.Win32.UnsafeNativeMethods.MapViewOfFile(memMappedFileHandle, MemoryMappedFile.GetFileMapAccess(access), dwFileOffsetHigh, dwFileOffsetLow, new UIntPtr(num3));
if (address.IsInvalid)
{
System.IO.__Error.WinIOError(Marshal.GetLastWin32Error(), string.Empty);
}
Microsoft.Win32.UnsafeNativeMethods.MEMORY_BASIC_INFORMATION buffer = new Microsoft.Win32.UnsafeNativeMethods.MEMORY_BASIC_INFORMATION();
Microsoft.Win32.UnsafeNativeMethods.VirtualQuery(address, ref buffer, (IntPtr) Marshal.SizeOf(buffer));
ulong regionSize = (ulong) buffer.RegionSize;
if ((buffer.State & 0x2000) != 0)
{
Microsoft.Win32.UnsafeNativeMethods.VirtualAlloc(address, (UIntPtr) regionSize, 0x1000, MemoryMappedFile.GetPageAccess(access));
int errorCode = Marshal.GetLastWin32Error();
if (address.IsInvalid)
{
System.IO.__Error.WinIOError(errorCode, string.Empty);
}
}
if (size == 0L)
{
size = (long) (regionSize - num);
}
address.Initialize(((ulong) size) + num);
return new MemoryMappedView(address, (long) num, size, access);
}
