/// <summary>
/// Sets protection on a block previously allocated with AllocateLarge.
/// </summary>
/// <param name="block">The starting memory address to set protection for.</param>
/// <param name="size">The size of the block.</param>
/// <param name="readAccess">Whether to allow read access.</param>
/// <param name="writeAccess">Whether to allow write access.</param>
/// <remarks>
/// You may not specify false for read access without also specifying false for write access.
/// Note to implementors: This method is not guaranteed to actually set read/write-ability
/// on a block of memory, and may instead be implemented as a no-op after parameter validation.
/// </remarks>
public static void ProtectBlockLarge(IntPtr block, ulong size, bool readAccess, bool writeAccess)
{
uint flOldProtect;
uint flNewProtect;
if (readAccess && writeAccess)
{
flNewProtect = NativeConstants.PAGE_READWRITE;
}
else if (readAccess && !writeAccess)
{
flNewProtect = NativeConstants.PAGE_READONLY;
}
else if (!readAccess && !writeAccess)
{
flNewProtect = NativeConstants.PAGE_NOACCESS;
}
else
{
throw new InvalidOperationException("May not specify a page to be write-only");
}
#if DEBUGSPEW
Tracing.Ping("ProtectBlockLarge: block #" + block.ToString() + ", read: " + readAccess + ", write: " + writeAccess);
#endif
SafeNativeMethods.VirtualProtect(block, new UIntPtr(size), flNewProtect, out flOldProtect);
}
