Pass an IO#ioctl spec

* The 3rd argument of ioctl() needs to be long to pass integer values to it.
  Otherwise, NFI doesn't accept an integer as a pointer.

src/main/ruby/core/io.rb

@@ -1724,7 +1724,7 @@ def internal_encoding
   # interpreted as a binary sequence of bytes (Array#pack
   # might be a useful way to build this string). On Unix
   # platforms, see fcntl(2) for details. Not implemented on all platforms.
-  def ioctl(command, arg=0)
+  def ioctl(command, arg = 0)
     ensure_open
 
     if !arg
@@ -1738,16 +1738,17 @@ def ioctl(command, arg=0)
       # Most Linux ioctl codes predate the convention, so a fallback like this
       # is still necessary.
       buffer_size = 4096 if buffer_size < 4096
-      buffer = FFI::MemoryPointer.new buffer_size
-      buffer.write_string arg, arg.bytesize
+      buffer = FFI::MemoryPointer.new(buffer_size)
+      buffer.write_string(arg, arg.bytesize)
       real_arg = buffer.address
     else
-      real_arg = Truffle::Type.coerce_to_int arg
+      real_arg = Truffle::Type.coerce_to_int(arg)
     end
 
-    command = Truffle::Type.coerce_to_int command
-    ret = Truffle::POSIX.ioctl descriptor, command, real_arg
+    command = Truffle::Type.coerce_to_int(command)
+    ret = Truffle::POSIX.ioctl(descriptor, command, real_arg)
     Errno.handle if ret < 0
+
     if arg.kind_of?(String)
       arg.replace buffer.read_string(buffer_size)
       buffer.free

src/main/ruby/core/posix.rb

@@ -181,7 +181,7 @@ def self.attach_function_eagerly(native_name, argument_types, return_type,
   attach_function :fsync, [:int], :int
   attach_function :ftruncate, [:int, :off_t], :int
   attach_function :getcwd, [:pointer, :size_t], :string
-  attach_function :ioctl, [:int, :ulong, :pointer], :int
+  attach_function :ioctl, [:int, :ulong, :long], :int
   attach_function :isatty, [:int], :int
   attach_function :lchmod, [:string, :mode_t], :int
   attach_function :lchown, [:string, :uid_t, :gid_t], :int