Implement automatic loading of dart:core_native_fields library

bin/gen_snapshot.cc

Index: bin/gen_snapshot.cc
===================================================================
--- bin/gen_snapshot.cc	(revision 1465)
+++ bin/gen_snapshot.cc	(working copy)
@@ -90,38 +90,42 @@
 }
 
 
+static Dart_Handle LibraryTagHandler(Dart_LibraryTag tag,
+                                     Dart_Handle library,
+                                     Dart_Handle url) {
+  const bool kDontImportBuiltinLib = false;  // Do not import builtin lib.
+  return LibraryTagHandlerHelper(tag, library, url, kDontImportBuiltinLib);
+}
+
+
 static void* SnapshotCreateCallback(void* data) {
   const char* script_name = reinterpret_cast<const char*>(data);
   Dart_Handle result;
+  Dart_Handle library;
   Dart_EnterScope();
 
   ASSERT(snapshot_filename != NULL);
 
-  // If a file is specified on the command line, load it up before a snapshot
-  // is created.
+  // load up the script before a snapshot is created.

[Anton Muhin, 2011/11/13 16:19:32]

nit: [L]oad the script

[siva, 2011/11/15 02:16:52]

Done.

   if (script_name != NULL) {
     // Load the specified script.
-    Dart_Handle library = LoadSnapshotCreationScript(script_name);
-    if (!Dart_IsValid(library)) {
-      const char* err_msg = Dart_GetError(library);
-      fprintf(stderr, "Errors encountered while loading script: %s\n", err_msg);
-      Dart_ExitScope();
-      exit(255);
-    }
-
-    if (!Dart_IsLibrary(library)) {
-      fprintf(stderr,
-              "Expected a library when loading script: %s",
-              script_name);
-      Dart_ExitScope();
-      exit(255);
-    }
+    library = LoadSnapshotCreationScript(script_name, LibraryTagHandler);
   } else {
-    // Implicitly load builtin library.
-    Builtin_LoadLibrary();
-    // Setup the native resolver for built in library functions.
-    Builtin_SetNativeResolver();
+    // This is a generic dart snapshot which needs builtin library
+    // setup.
+    library = Builtin_LoadLibrary(LibraryTagHandler);

[Anton Muhin, 2011/11/13 16:19:32]

cannot you migrate to the common infrastructure for DartVM bin snapshoting now? 
might be a good experiment in dogfooding.

[siva, 2011/11/15 02:16:52]

I would have if we had a 'builtin.dart' file to use but we concat all dart files
into a Builtin_source_ C array and hence the URL mapping scheme is not valid
here.
Maybe in another CL after the URL mapping CL has landed I can remove the step
which auto generates Builtin_source_ and instead auto generate a
'builtin_gen.dart' file which contains #source... of all the other files.

On 2011/11/13 16:19:32, antonmuhin wrote:

[Anton Muhin, 2011/11/15 12:22:23]

sure

On 2011/11/15 02:16:52, asiva wrote:

   }
+  if (!Dart_IsValid(library)) {
+    const char* err_msg = Dart_GetError(library);
+    fprintf(stderr, "Errors encountered while loading script: %s\n", err_msg);
+    Dart_ExitScope();
+    exit(255);
+  }
+  if (!Dart_IsLibrary(library)) {

[Anton Muhin, 2011/11/13 16:19:32]

should it be an assert?  esp. with new API.

[siva, 2011/11/15 02:16:52]

No we want to fail if we don't find a library object here.

On 2011/11/13 16:19:32, antonmuhin wrote:

[Anton Muhin, 2011/11/15 12:22:23]

Is it a possible case when Builtin_LoadLibrary successfully finished (as checked
by Dart_IsValid) and still returned something different from a lib?

On 2011/11/15 02:16:52, asiva wrote:

[siva, 2011/11/15 19:42:49]

I see what you are saying.
Changed to an ASSERT.

On 2011/11/15 12:22:23, antonmuhin wrote:

+    fprintf(stderr, "Expected a library when loading script: %s", script_name);
+    Dart_ExitScope();
+    exit(255);
+  }
 
   uint8_t* buffer = NULL;
   intptr_t size = 0;