- Refactor the isolate callback mechanism to also include creation of the

bin/main.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // 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 <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "include/dart_api.h"
 
 #include "bin/builtin.h"
 #include "bin/dartutils.h"
 #include "bin/file.h"
 #include "bin/globals.h"
 
 // snapshot_buffer points to a snapshot if we link in a snapshot otherwise
 // it is initialized to NULL.
 extern const uint8_t* snapshot_buffer;
 
 
+// Global state that stores a pointer to the application script file.
+static char* canonical_script_name = NULL;
+
+
 // Global state that indicates whether pprof symbol information is
 // to be generated or not.
 static const char* generate_pprof_symbols_filename = NULL;
 
 
 static bool IsValidFlag(const char* name,
                         const char* prefix,
                         intptr_t prefix_length) {
   intptr_t name_length = strlen(name);
   return ((name_length > prefix_length) &&
@@ skipping 148 matching lines @@
       return url;
     }
     // Create a canonical path based on the including library and current url.
     return DartUtils::CanonicalizeURL(NULL, library, url_string);
   }
   if (is_dart_scheme_url) {
     return Dart_Error("Do not know how to load '%s'", url_string);
   }
   result = DartUtils::LoadSource(NULL, library, url, tag, url_string);
   if (!Dart_IsError(result) && (tag == kImportTag)) {
-    Builtin_ImportLibrary(result);
+    Builtin::ImportLibrary(result);
   }
   return result;
 }
 
 
 static Dart_Handle LoadScript(const char* script_name) {
   Dart_Handle source = DartUtils::ReadStringFromFile(script_name);
   if (Dart_IsError(source)) {
     return source;
   }
   Dart_Handle url = Dart_NewString(script_name);
 
   return Dart_LoadScript(url, source, LibraryTagHandler);
 }
 
 
-static void* MainIsolateInitCallback(void* data) {
-  const char* script_name = reinterpret_cast<const char*>(data);
+static bool CreateIsolateAndSetup(Dart_IsolateError error) {
+  Dart_Isolate isolate = Dart_CreateIsolate(snapshot_buffer);
+  if (isolate == NULL) {
+    snprintf(const_cast<char*>(error.buffer), error.length,
+             "Creation/Bootstrap of Isolate failed");

[turnidge, 2011/11/23 18:05:12]

If Dart_CreateIsolate took a Dart_IsolateError parameter, then we could return
that here to provide a more detailed error message.

[siva, 2011/11/23 22:37:27]

Done.

+    return false;
+  }
+
   Dart_Handle library;
   Dart_EnterScope();
 
-  // Load the specified script.
-  library = LoadScript(script_name);
+  // Load the specified application script into the newly created isolate.
+  library = LoadScript(canonical_script_name);
   if (Dart_IsError(library)) {
-    const char* err_msg = Dart_GetError(library);
-    fprintf(stderr, "Errors encountered while loading script: %s\n", err_msg);
+    snprintf(const_cast<char*>(error.buffer), error.length,
+             "%s", Dart_GetError(library));

[turnidge, 2011/11/23 18:05:12]

Should we use OS::SNPrint instead of snprintf?  Same comment applies in
bin/gen_snapshot.cc.

[siva, 2011/11/23 22:37:27]

OS class is not avaialble here as it is the embedder code and I noticed that the
windows port has also been using snprintf. As discussed offline I am going to
leave it as snprintf. If needed we can do another sweep over all snprintf calls
and replace them with a Dart_ api call.

On 2011/11/23 18:05:12, turnidge wrote:

[turnidge, 2011/11/28 18:39:58]

Ok.

On 2011/11/23 22:37:27, asiva wrote:

     Dart_ExitScope();
-    exit(255);
+    Dart_ShutdownIsolate();
+    return false;
   }
   if (!Dart_IsLibrary(library)) {
-    fprintf(stderr,
-            "Expected a library when loading script: %s",
-            script_name);
+    snprintf(const_cast<char*>(error.buffer), error.length,
+             "Expected a library when loading script: %s",
+             canonical_script_name);
     Dart_ExitScope();
-    exit(255);
+    Dart_ShutdownIsolate();
+    return false;
   }
-  Builtin_ImportLibrary(library);  // Import builtin library.
-
+  Builtin::ImportLibrary(library);  // Implicitly import builtin into app.
+  if (snapshot_buffer != NULL) {
+    // Setup the native resolver as the snapshot does not carry it.
+    Builtin::SetNativeResolver();
+  }

[turnidge, 2011/11/23 18:05:12]

Do we want to provide embedders with access to our Builtin:: stuff so that they
can override the Isolate creation callback but still use our builtin libraries?

[siva, 2011/11/23 22:37:27]

The Builtin stuff is in our dart embedder, this comes back to having a dartutils
library that other embedders could link against.

On 2011/11/23 18:05:12, turnidge wrote:

[turnidge, 2011/11/28 18:39:58]

Ok.

On 2011/11/23 22:37:27, asiva wrote:

   Dart_ExitScope();
-  return data;
+  return true;
 }
 
 
 static void PrintUsage() {
   fprintf(stderr,
           "dart [<vm-flags>] <dart-script-file> [<dart-options>]\n");
 }
 
 
 static bool HasCompileAll(const CommandLineOptions& options) {
@@ skipping 18 matching lines @@
                      &script_name,
                      &dart_options) < 0) {
     PrintUsage();
     return 255;
   }
 
   // Initialize the Dart VM (TODO(asiva) - remove const_cast once
   // dart API is fixed to take a const char** in Dart_Initialize).
   Dart_Initialize(vm_options.count(),
                   vm_options.arguments(),
-                  MainIsolateInitCallback);
+                  CreateIsolateAndSetup);
 
-  // Create an isolate. As a side effect, MainIsolateInitCallback
-  // gets called, which loads the scripts and libraries.
-  char* canonical_script_name = File::GetCanonicalPath(script_name);
+  canonical_script_name = File::GetCanonicalPath(script_name);
   if (canonical_script_name == NULL) {
     fprintf(stderr, "Unable to find '%s'\n", script_name);
     return 255;  // Indicates we encountered an error.
   }
-  Dart_Isolate isolate = Dart_CreateIsolate(snapshot_buffer,
-                                            canonical_script_name);
-  if (isolate == NULL) {
+
+  // Call CreateIsolateAndSetup which creates an isolate and loads up
+  // the specified application script.
+  Dart_IsolateError error;
+  static const int kErrorMsgLength = 256;
+  error.buffer = reinterpret_cast<char*>(malloc(kErrorMsgLength));
+  error.length = kErrorMsgLength;
+  if (!CreateIsolateAndSetup(error)) {
+    fprintf(stderr, "%s\n", error.buffer);
     free(canonical_script_name);
-    return 255;
+    free(error.buffer);
+    return 255;  // Indicates we encountered an error.
   }
+  free(error.buffer);
+
+  Dart_Isolate isolate = Dart_CurrentIsolate();
+  ASSERT(isolate != NULL);
+  Dart_Handle result;
 
   Dart_EnterScope();
 
-  if (snapshot_buffer != NULL) {
-    // Setup the native resolver as the snapshot does not carry it.
-    Builtin_SetNativeResolver();
-  }
-
   if (HasCompileAll(vm_options)) {
-    Dart_Handle result = Dart_CompileAll();
+    result = Dart_CompileAll();
     if (Dart_IsError(result)) {
       fprintf(stderr, "%s\n", Dart_GetError(result));
       Dart_ExitScope();
       Dart_ShutdownIsolate();
       free(canonical_script_name);
       return 255;  // Indicates we encountered an error.
     }
   }
 
   // Create a dart options object that can be accessed from dart code.
   Dart_Handle options_result = SetupRuntimeOptions(&dart_options);
   if (Dart_IsError(options_result)) {
     fprintf(stderr, "%s\n", Dart_GetError(options_result));
     Dart_ExitScope();
     Dart_ShutdownIsolate();
     free(canonical_script_name);
     return 255;  // Indicates we encountered an error.
   }
 
   // Lookup and invoke the top level main function.
   Dart_Handle script_url = Dart_NewString(canonical_script_name);
   Dart_Handle library = Dart_LookupLibrary(script_url);
   if (Dart_IsError(library)) {
     fprintf(stderr, "%s\n", Dart_GetError(library));
     Dart_ExitScope();
     Dart_ShutdownIsolate();
     free(canonical_script_name);
     return 255;  // Indicates we encountered an error.
   }
-  Dart_Handle result = Dart_InvokeStatic(library,
-                                         Dart_NewString(""),
-                                         Dart_NewString("main"),
-                                         0,
-                                         NULL);
+  result = Dart_InvokeStatic(library,
+                             Dart_NewString(""),
+                             Dart_NewString("main"),
+                             0,
+                             NULL);
   if (Dart_IsError(result)) {
     fprintf(stderr, "%s\n", Dart_GetError(result));
     Dart_ExitScope();
     Dart_ShutdownIsolate();
     free(canonical_script_name);
     return 255;  // Indicates we encountered an error.
   }
   // Keep handling messages until the last active receive port is closed.
   result = Dart_RunLoop();
   if (Dart_IsError(result)) {
     fprintf(stderr, "%s\n", Dart_GetError(result));
     Dart_ExitScope();
     Dart_ShutdownIsolate();
     free(canonical_script_name);
     return 255;  // Indicates we encountered an error.
   }
   free(canonical_script_name);
   Dart_ExitScope();
   // Dump symbol information for the profiler.
   DumpPprofSymbolInfo();
   // Shutdown the isolate.
   Dart_ShutdownIsolate();
   return 0;
 }