[GR-8319] Make RFFI implementation aware of R embedding.

PullRequest: fastr/1406

com.oracle.truffle.r.engine/src/com/oracle/truffle/r/engine/shell/REmbedded.java

@@ -71,7 +71,7 @@ public class REmbedded {
      * initialize FastR as we cannot do that until the embedding system has had a chance to adjust
      * the {@link RStartParams}, which happens after this call returns.
      */
-    private static void initializeR(String[] args) {
+    private static void initializeR(String[] args, boolean initMainLoop) {
         assert context == null;
         RContext.setEmbedded();
         RCmdOptions options = RCmdOptions.parseArguments(RCmdOptions.Client.R, args, false);
@@ -86,6 +86,14 @@ public class REmbedded {
         context = Context.newBuilder().allowHostAccess(true).arguments("R", options.getArguments()).in(input).out(stdOut).err(stdErr).build();
         consoleHandler.setContext(context);
         context.eval(INIT);
+
+        if (initMainLoop) {
+            context.enter();
+            RContext ctx = RContext.getInstance();
+            ctx.completeEmbeddedInitialization();
+            ctx.getRFFI().initializeEmbedded(ctx);
+            // stay in the context TODO should we?
+        }
     }
 
     /**
@@ -110,12 +118,10 @@ public class REmbedded {
      */
     private static final Source INIT = Source.newBuilder("R", "1", "<embedded>").buildLiteral();
 
-    /**
-     * GnuR distinguishes {@code setup_Rmainloop} and {@code run_Rmainloop}. Currently we don't have
-     * the equivalent separation in FastR.
-     */
-    private static void setupRmainloop() {
-        // nothing to do
+    private static void endRmainloop(int status) {
+        context.leave();
+        context.close();
+        Utils.systemExit(status);
     }
 
     /**
@@ -124,7 +130,9 @@ public class REmbedded {
      */
     private static void runRmainloop() {
         context.enter();
-        RContext.getInstance().completeEmbeddedInitialization();
+        RContext ctx = RContext.getInstance();
+        ctx.completeEmbeddedInitialization();
+        ctx.getRFFI().initializeEmbedded(ctx);
         int status = RCommand.readEvalPrint(context, consoleHandler);
         context.leave();
         context.close();
@@ -135,8 +143,7 @@ public class REmbedded {
      * Testing vehicle, emulates a native upcall.
      */
     public static void main(String[] args) {
-        initializeR(args);
-        setupRmainloop();
+        initializeR(args, false);
         runRmainloop();
     }
 

com.oracle.truffle.r.ffi.impl/src/com/oracle/truffle/r/ffi/impl/managed/Managed_DownCallNodeFactory.java

@@ -35,6 +35,7 @@ import java.util.List;
 import java.util.Set;
 
 import com.oracle.truffle.api.CallTarget;
+import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.Truffle;
 import com.oracle.truffle.api.frame.VirtualFrame;
 import com.oracle.truffle.api.interop.ForeignAccess;
@@ -140,6 +141,7 @@ public final class Managed_DownCallNodeFactory extends DownCallNodeFactory {
                 public CallTarget accessExecute(int argumentsLength) {
                     return Truffle.getRuntime().createCallTarget(new RootNode(null) {
                         @Override
+                        @TruffleBoundary
                         public Object execute(VirtualFrame frame) {
                             NativeCharArray templateBytes = (NativeCharArray) ForeignAccess.getArguments(frame).get(0);
                             String template = new String(templateBytes.getValue(), 0, templateBytes.getValue().length - 1);
@@ -191,6 +193,7 @@ public final class Managed_DownCallNodeFactory extends DownCallNodeFactory {
                 public CallTarget accessExecute(int argumentsLength) {
                     return Truffle.getRuntime().createCallTarget(new RootNode(null) {
                         @Override
+                        @TruffleBoundary
                         public Object execute(VirtualFrame frame) {
                             NativeCharArray buffer = (NativeCharArray) ForeignAccess.getArguments(frame).get(0);
                             byte[] bytes = Paths.get(".").toAbsolutePath().normalize().toString().getBytes();

com.oracle.truffle.r.ffi.impl/src/com/oracle/truffle/r/ffi/impl/nfi/TruffleNFI_Context.java

@@ -196,6 +196,11 @@ final class TruffleNFI_Context extends RFFIContext {
         }
     }
 
+    @Override
+    public void initializeEmbedded(RContext context) {
+        pushCallbacks();
+    }
+
     @TruffleBoundary
     private long initCallbacksAddress() {
         // get the address of the native thread local

com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/ffi/RFFIContext.java

 /*
- * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,6 +28,7 @@ import java.util.concurrent.atomic.AtomicInteger;
 
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
 import com.oracle.truffle.api.interop.TruffleObject;
+import com.oracle.truffle.r.runtime.RInternalError;
 import com.oracle.truffle.r.runtime.context.RContext;
 import com.oracle.truffle.r.runtime.data.RObject;
 
@@ -101,6 +102,17 @@ public abstract class RFFIContext extends RFFI {
     public void initializeVariables(RContext context) {
     }
 
+    /**
+     * Invoked as part of the R embedded initialization just before returning back to the C user
+     * code. Should do any set-up necessary for the RFFI to be fully functional even outside the
+     * context of a down-call. At the moment the assumption is that embedded code is always single
+     * threaded and always creates exactly one context. This method shall be invoked after
+     * {@link #initialize(RContext)} and {@link #initializeVariables(RContext)}.
+     */
+    public void initializeEmbedded(RContext context) {
+        throw RInternalError.unimplemented("R Embedding not supported with " + this.getClass().getSimpleName() + " RFFI backend.");
+    }
+
     public long beforeDowncall() {
         callDepth++;
         return 0;

com.oracle.truffle.r.runtime/src/com/oracle/truffle/r/runtime/ffi/interop/NativeCharArray.java

@@ -58,6 +58,7 @@ public final class NativeCharArray extends NativeUInt8Array {
     /**
      * Finds the null terminator and creates the Java String accordingly.
      */
+    @TruffleBoundary
     public String getStringFromOutputBuffer() {
         assert !fakesNullTermination() : "create the buffer string via createOutputBuffer()";
         byte[] mbuf = getValue();