Define rb_encoding as const OnigEncodingType like MRI

* Save the loaded libtruffleruby so we can easily call to it from Ruby.

Author: eregon

lib/cext/include/ruby/encoding.h

@@ -108,9 +108,7 @@ void RB_ENC_CODERANGE_SET(VALUE obj, int cr);
 #define ENC_CODERANGE_AND(a, b)      RB_ENC_CODERANGE_AND(a, b)
 #define ENCODING_CODERANGE_SET(obj, encindex, cr) RB_ENCODING_CODERANGE_SET(obj, encindex, cr)
 
-typedef struct rb_encoding {
-  char *name;
-} rb_encoding;
+typedef const OnigEncodingType rb_encoding;
 
 int rb_char_to_option_kcode(int c, int *option, int *kcode);
 

lib/truffle/truffle/cext.rb

@@ -72,6 +72,14 @@ module Truffle::CExt
   RUBY_ECONV_PARTIAL_INPUT = Encoding::Converter::PARTIAL_INPUT
   RUBY_ECONV_AFTER_OUTPUT = Encoding::Converter::AFTER_OUTPUT
 
+  SET_LIBTRUFFLERUBY = -> libtruffleruby do
+    LIBTRUFFLERUBY = libtruffleruby
+  end
+
+  def self.register_libtruffleruby(libtruffleruby)
+    SET_LIBTRUFFLERUBY.call(libtruffleruby)
+  end
+
   def supported?
     Interop.mime_type_supported?('application/x-sulong-library')
   end

lib/truffle/truffle/cext_structs.rb

@@ -430,7 +430,7 @@ def self.get_encoding_from_native(rbencoding_ptr)
   def initialize(encoding)
     @encoding = encoding
     @pointer = nil
-    @name = nil
+    @name = Truffle::CExt::LIBTRUFFLERUBY.RSTRING_PTR_IMPL(Primitive.cext_wrap(encoding.name))
   end
 
   private
@@ -445,12 +445,11 @@ def polyglot_members(internal)
 
   def polyglot_read_member(name)
     raise Truffle::Interop::UnknownIdentifierException unless name == 'name'
-    @name or raise '@name not set'
+    @name
   end
 
   def polyglot_write_member(name, value)
-    raise Truffle::Interop::UnknownIdentifierException unless name == 'name'
-    @name = value
+    raise Truffle::Interop::UnsupportedMessageException
   end
 
   def polyglot_remove_member(name)
@@ -466,7 +465,7 @@ def polyglot_member_readable?(name)
   end
 
   def polyglot_member_modifiable?(name)
-    name == 'name'
+    false
   end
 
   def polyglot_member_removable?(name)
@@ -498,24 +497,15 @@ def polyglot_pointer?
   end
 
   def polyglot_to_native
-    name = @name or raise '@name not set'
-    unless Truffle::Interop.pointer?(name)
-      Truffle::Interop.to_native(name)
-      raise "#{name.inspect} could not be converted to native" unless Truffle::Interop.pointer?(name)
-    end
-    name_address = Truffle::Interop.as_pointer(name)
-
     ENCODING_CACHE_MUTEX.synchronize do
       unless @pointer
-        @pointer = Truffle::FFI::MemoryPointer.new(:pointer, 1)
-        @pointer.write_pointer name_address
-
-        NATIVE_CACHE[@pointer.address] = self
+        @pointer = Truffle::CExt::LIBTRUFFLERUBY.rb_encoding_to_native(@name)
+        NATIVE_CACHE[Truffle::Interop.as_pointer(@pointer)] = self
       end
     end
   end
 
   def polyglot_as_pointer
-    @pointer.address
+    Truffle::Interop.as_pointer(@pointer)
   end
 end

src/main/c/cext/encoding.c

@@ -3,14 +3,18 @@
 
 // Encoding, rb_enc_*
 
-POLYGLOT_DECLARE_STRUCT(rb_encoding)
+POLYGLOT_DECLARE_TYPE(rb_encoding)
 
 // returns Truffle::CExt::RbEncoding, takes Encoding or String
 rb_encoding* rb_to_encoding(VALUE encoding) {
   encoding = RUBY_CEXT_INVOKE("rb_convert_to_encoding", encoding); // Convert to Encoding
-  rb_encoding *enc = polyglot_as_rb_encoding(RUBY_CEXT_INVOKE_NO_WRAP("rb_to_encoding", encoding));
-  enc->name = RSTRING_PTR(RUBY_INVOKE(encoding, "name"));
-  return enc;
+  return polyglot_as_rb_encoding(RUBY_CEXT_INVOKE_NO_WRAP("rb_to_encoding", encoding));
+}
+
+rb_encoding* rb_encoding_to_native(char* name) {
+  OnigEncodingType* native = calloc(1, sizeof(rb_encoding)); // calloc() to zero-fill
+  native->name = name;
+  return native;
 }
 
 rb_encoding* rb_default_external_encoding(void) {

src/main/java/org/truffleruby/language/loader/FeatureLoader.java

@@ -42,10 +42,8 @@
 
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.TruffleFile;
-import com.oracle.truffle.api.interop.ArityException;
+import com.oracle.truffle.api.interop.InteropException;
 import com.oracle.truffle.api.interop.InteropLibrary;
-import com.oracle.truffle.api.interop.UnsupportedMessageException;
-import com.oracle.truffle.api.interop.UnsupportedTypeException;
 import com.oracle.truffle.api.object.DynamicObject;
 import com.oracle.truffle.api.profiles.ConditionProfile;
 import com.oracle.truffle.api.source.Source;
@@ -423,9 +421,13 @@ public void ensureCExtImplementationLoaded(String feature, RequireNode requireNo
                 final Object initFunction = requireNode
                         .findFunctionInLibrary(library, "rb_tr_init", rubyLibPath);
 
+                final InteropLibrary interop = InteropLibrary.getFactory().getUncached();
                 try {
-                    InteropLibrary.getFactory().getUncached(initFunction).execute(initFunction, truffleCExt);
-                } catch (UnsupportedTypeException | ArityException | UnsupportedMessageException e) {
+                    // rb_tr_init(Truffle::CExt)
+                    interop.execute(initFunction, truffleCExt);
+                    // Truffle::CExt.register_libtruffleruby(libtruffleruby)
+                    interop.invokeMember(truffleCExt, "register_libtruffleruby", library);
+                } catch (InteropException e) {
                     throw new JavaException(e);
                 }
             } finally {