Fuchsia: Hello, Fuchsia!

runtime/bin/fuchsia_test.cc

Index: runtime/bin/fuchsia_test.cc
diff --git a/runtime/bin/fuchsia_test.cc b/runtime/bin/fuchsia_test.cc
index e92014089d56e40cc25de3ba8d8f80e4c610f576..c6670b4dd2653ef2b538b12e971f490086fe8a52 100644
--- a/runtime/bin/fuchsia_test.cc
+++ b/runtime/bin/fuchsia_test.cc
@@ -2,21 +2,140 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+#include <dart_api.h>
 #include <stdio.h>
 #include <stdlib.h>
-
-#include <dart_api.h>
+#include <string.h>
 
 #include "bin/log.h"
+#include "platform/assert.h"
+
+const char* kBuiltinScript =
+    "_printString(String line) native \"Builtin_PrintString\";\n"
+    "_getPrintClosure() => _printString;\n";
+
+const char* kHelloWorldScript = "main() { print(\"Hello, Fuchsia!\"); }";
 
 namespace dart {
 namespace bin {
 
+static void Builtin_PrintString(Dart_NativeArguments args) {
+  intptr_t length = 0;
+  uint8_t* chars = NULL;
+  Dart_Handle str = Dart_GetNativeArgument(args, 0);
+  Dart_Handle result = Dart_StringToUTF8(str, &chars, &length);
+  if (Dart_IsError(result)) {
+    Dart_PropagateError(result);
+  }
+  // Uses fwrite to support printing NUL bytes.
+  intptr_t res = fwrite(chars, 1, length, stdout);
+  ASSERT(res == length);
+  fputs("\n", stdout);
+  fflush(stdout);
+}
+
+static Dart_NativeFunction NativeLookup(Dart_Handle name,
+                                        int argument_count,
+                                        bool* auto_setup_scope) {
+  const char* function_name = NULL;
+  Dart_Handle err = Dart_StringToCString(name, &function_name);
+  DART_CHECK_VALID(err);
+  *auto_setup_scope = true;
+  if (strcmp(function_name, "Builtin_PrintString") == 0) {
+    return reinterpret_cast<Dart_NativeFunction>(Builtin_PrintString);
+  }
+  return NULL;
+}
+
+static const uint8_t* NativeSymbol(Dart_NativeFunction nf) {
+  if (reinterpret_cast<Dart_NativeFunction>(Builtin_PrintString) == nf) {
+    return reinterpret_cast<const uint8_t*>("Builtin_PrintString");
+  }
+  return NULL;
+}
+
+static Dart_Handle PrepareBuiltinLibrary(const char* script) {
+  Log::Print("Creating builtin library uri\n");
+  Dart_Handle builtin_uri = Dart_NewStringFromCString("builtin_uri");
+  DART_CHECK_VALID(builtin_uri);
+
+  Log::Print("Creating builtin library script string\n");
+  Dart_Handle builtin_script = Dart_NewStringFromCString(script);
+  DART_CHECK_VALID(builtin_script);
+
+  Log::Print("Loading builtin library\n");
+  Dart_Handle status = Dart_LoadLibrary(builtin_uri, builtin_script, 0, 0);
+  DART_CHECK_VALID(status);
+
+  Log::Print("Looking up builtin library\n");
+  Dart_Handle builtin_library = Dart_LookupLibrary(builtin_uri);
+  DART_CHECK_VALID(builtin_library);
+
+  Log::Print("Setting up native resolver for builtin library\n");
+  status = Dart_SetNativeResolver(builtin_library, NativeLookup, NativeSymbol);
+  DART_CHECK_VALID(status);
+
+  return builtin_library;
+}
+
+static Dart_Handle PrepareScriptLibrary(const char* script) {
+  Log::Print("Creating script URI string\n");
+  Dart_Handle script_uri = Dart_NewStringFromCString("script_uri");
+  DART_CHECK_VALID(script_uri);
+
+  Log::Print("Creating script string\n");
+  Dart_Handle script_string = Dart_NewStringFromCString(script);
+  DART_CHECK_VALID(script_string);
+
+  Log::Print("Loading script into new library\n");
+  Dart_Handle status = Dart_LoadLibrary(script_uri, script_string, 0, 0);
+  DART_CHECK_VALID(status);
+
+  Log::Print("Looking up script library\n");
+  Dart_Handle library = Dart_LookupLibrary(script_uri);
+  DART_CHECK_VALID(library);
+
+  return library;
+}
+
+static Dart_Handle LoadInternalLibrary() {
+  Log::Print("Creating internal library uri string\n");
+  Dart_Handle url = Dart_NewStringFromCString("dart:_internal");
+  DART_CHECK_VALID(url);
+
+  Log::Print("Looking up internal library\n");
+  Dart_Handle internal_library = Dart_LookupLibrary(url);
+  DART_CHECK_VALID(internal_library);
+
+  return internal_library;
+}
+
+static void PreparePrintClosure(Dart_Handle builtin_library,
+                                Dart_Handle internal_library) {
+  Log::Print("Creating _getPrintClosure name string\n");
+  Dart_Handle get_print_closure_name =
+      Dart_NewStringFromCString("_getPrintClosure");
+  DART_CHECK_VALID(get_print_closure_name);
+
+  Log::Print("Invoking _getPrintClosure\n");
+  Dart_Handle print_closure = Dart_Invoke(
+      builtin_library, get_print_closure_name, 0, NULL);
+  DART_CHECK_VALID(print_closure);
+
+  Log::Print("Creating _printClosure name string\n");
+  Dart_Handle print_closure_name = Dart_NewStringFromCString("_printClosure");
+  DART_CHECK_VALID(print_closure_name);
+
+  Log::Print("Setting _printClosure to result of _getPrintClosure\n");
+  Dart_Handle status = Dart_SetField(
+      internal_library, print_closure_name, print_closure);
+  DART_CHECK_VALID(status);
+}
+
 int Main() {
   Log::Print("Calling Dart_SetVMFlags\n");
   if (!Dart_SetVMFlags(0, NULL)) {
-    Log::PrintErr("Failed to set flags\n");
-    return -1;
+    FATAL("Failed to set flags\n");
   }
   Log::Print("Calling Dart_Initialize\n");
   char* error = Dart_Initialize(
@@ -30,17 +149,54 @@ int Main() {
       NULL,
       NULL);
   if (error != NULL) {
-    Log::PrintErr("VM initialization failed: %s\n", error);
-    free(error);
-    return -1;
+    FATAL1("VM initialization failed: %s\n", error);
   }
 
+  Log::Print("Creating Isolate\n");
+  Dart_Isolate isolate = Dart_CreateIsolate(
+      "script_uri",
+      "main",
+      NULL,
+      NULL,
+      NULL,
+      &error);
+  if (isolate == NULL) {
+    FATAL1("Dart_CreateIsolate failed: %s\n", error);
+  }
+
+  Log::Print("Entering Scope\n");
+  Dart_EnterScope();
+
+  Dart_Handle library = PrepareScriptLibrary(kHelloWorldScript);
+
+  Dart_Handle builtin_library = PrepareBuiltinLibrary(kBuiltinScript);
+
+  Log::Print("Finalizing loading\n");
+  Dart_Handle status = Dart_FinalizeLoading(false);
+  DART_CHECK_VALID(status);
+
+  Dart_Handle internal_library = LoadInternalLibrary();
+
+  PreparePrintClosure(builtin_library, internal_library);
+
+  Log::Print("Creating main string\n");
+  Dart_Handle main_name = Dart_NewStringFromCString("main");
+  DART_CHECK_VALID(main_name);
+
+  Log::Print("---- Invoking main() ----\n");
+  status = Dart_Invoke(library, main_name, 0, NULL);
+  DART_CHECK_VALID(status);
+  Log::Print("---- main() returned ----\n");
+
+  Log::Print("Exiting Scope\n");
+  Dart_ExitScope();
+  Log::Print("Shutting down the isolate\n");
+  Dart_ShutdownIsolate();
+
   Log::Print("Calling Dart_Cleanup\n");
   error = Dart_Cleanup();
   if (error != NULL) {
-    Log::PrintErr("VM Cleanup failed: %s\n", error);
-    free(error);
-    return -1;
+    FATAL1("VM Cleanup failed: %s\n", error);
   }
 
   Log::Print("Success!\n");