Remove FFI constant from File/IO to fix issue extending FFI from File

Author: bjfish

CHANGELOG.md

@@ -9,6 +9,7 @@ Bug fixes:
 * Fixed return value of `Enumerable#first` (#2056, @LillianZ).
 * Improve reliability of the post install hook by disabling RubyGems (#2075).
 * Fixed top level exception handler to print exception cause (#2013).
+* Fixed issue when extending FFI from File (#2094).
 
 Compatibility:
 

src/main/ruby/truffleruby/core/file.rb

@@ -102,8 +102,6 @@ module Constants
     FNM_SYSCASE = File::FNM_SYSCASE
   end
 
-  FFI = Truffle::FFI
-
   SEPARATOR = '/'
   Separator = SEPARATOR
   ALT_SEPARATOR = nil
@@ -847,7 +845,7 @@ def self.readable_real?(path)
   #  File.symlink("testfile", "link2test")   #=> 0
   #  File.readlink("link2test")              #=> "testfile"
   def self.readlink(path)
-    FFI::MemoryPointer.new(Truffle::Platform::PATH_MAX) do |ptr|
+    Truffle::FFI::MemoryPointer.new(Truffle::Platform::PATH_MAX) do |ptr|
       n = POSIX.readlink Truffle::Type.coerce_to_path(path), ptr, Truffle::Platform::PATH_MAX
       Errno.handle if n == -1
 

src/main/ruby/truffleruby/core/io.rb

@@ -35,7 +35,6 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 class IO
-  FFI = Truffle::FFI
 
   include Enumerable
 
@@ -1560,7 +1559,7 @@ 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 = Truffle::FFI::MemoryPointer.new(buffer_size)
       buffer.write_string(arg, arg.bytesize)
       real_arg = buffer.address
     else