private PagerState CreatePagerState()
{
var startingBaseAddressPtr = Syscall.mmap(IntPtr.Zero, (UIntPtr)_totalAllocationSize,
MmapProts.PROT_READ | MmapProts.PROT_WRITE,
MmapFlags.MAP_SHARED, _fd, IntPtr.Zero);
if (startingBaseAddressPtr.ToInt64() == -1) //system didn't succeed in mapping the address where we wanted
{
var err = Marshal.GetLastWin32Error();
PosixHelper.ThrowLastError(err, "mmap on " + FileName);
}
NativeMemory.RegisterFileMapping(FileName, startingBaseAddressPtr, _totalAllocationSize);
var allocationInfo = new PagerState.AllocationInfo
{
BaseAddress = (byte *)startingBaseAddressPtr.ToPointer(),
Size = _totalAllocationSize,
MappedFile = null
};
var newPager = new PagerState(this)
{
Files = null, // unused
MapBase = allocationInfo.BaseAddress,
AllocationInfos = new[] { allocationInfo }
};
return(newPager);
}
private PagerState CreatePagerState()
{
var fileSize = GetFileSize();
var startingBaseAddressPtr = Syscall.mmap(IntPtr.Zero, (ulong)fileSize,
MmapProts.PROT_READ | MmapProts.PROT_WRITE,
MmapFlags.MAP_SHARED, _fd, 0);
if (startingBaseAddressPtr.ToInt64() == -1) //system didn't succeed in mapping the address where we wanted
{
PosixHelper.ThrowLastError(Marshal.GetLastWin32Error());
}
var allocationInfo = new PagerState.AllocationInfo
{
BaseAddress = (byte *)startingBaseAddressPtr.ToPointer(),
Size = fileSize,
MappedFile = null
};
var newPager = new PagerState(this)
{
Files = null, // unused
MapBase = allocationInfo.BaseAddress,
AllocationInfos = new[] { allocationInfo }
};
newPager.AddRef(); // one for the pager
return(newPager);
}
private PagerState.AllocationInfo RemapViewOfFileAtAddress(long allocationSize, long offsetInFile, byte *baseAddress)
{
var intPtr = Syscall.mmap(new IntPtr(baseAddress), (ulong)allocationSize,
MmapProts.PROT_READ | MmapProts.PROT_WRITE,
MmapFlags.MAP_FIXED | MmapFlags.MAP_SHARED, _fd, offsetInFile);
if (intPtr.ToInt64() == -1)
{
return(null); // couldn't map to the right place
}
return(new PagerState.AllocationInfo
{
BaseAddress = baseAddress,
Size = allocationSize,
});
}