Do not try to serialize VM objects, these are read only canonical objects and should be referred to…

vm/dart_api_message.cc

 // Copyright (c) 2012, 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 "vm/dart_api_message.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
+#include "vm/symbols.h"
 
 namespace dart {
 
 // TODO(sgjesse): When the external message format is done these
 // duplicate constants from snapshot.cc should be removed.
 enum {
   kInstanceId = ObjectStore::kMaxId,
   kMaxPredefinedObjectIds,
 };
 static const int kNumInitialReferences = 4;
@@ skipping 21 matching lines @@
 }
 
 
 Dart_CObject* ApiMessageReader::ReadMessage() {
   // Read the object out of the message.
   return ReadObject();
 }
 
 
 intptr_t ApiMessageReader::LookupInternalClass(intptr_t class_header) {
-  SerializedHeaderType header_type = SerializedHeaderTag::decode(class_header);
-  ASSERT(header_type == kObjectId);
-  intptr_t header_value = SerializedHeaderData::decode(class_header);
-  return header_value;
+  if (IsVMIsolateObject(class_header)) {
+    return GetVMIsolateObjectId(class_header);
+  }
+  ASSERT(SerializedHeaderTag::decode(class_header) == kObjectId);
+  return SerializedHeaderData::decode(class_header);
 }
 
 
 Dart_CObject* ApiMessageReader::AllocateDartCObject(Dart_CObject::Type type) {
   Dart_CObject* value =
       reinterpret_cast<Dart_CObject*>(alloc_(NULL, 0, sizeof(Dart_CObject)));
   ASSERT(value != NULL);
   value->type = type;
   return value;
 }
@@ skipping 147 matching lines @@
     for (int i = 0; i < len; i++) {
       value->value.as_array.values[i] = ReadObjectRef();
     }
     return value;
   }
 
   return ReadInternalVMObject(class_id, object_id);
 }
 
 
+Dart_CObject* ApiMessageReader::ReadVMSymbol(intptr_t object_id) {
+  if (Symbols::IsVMSymbolId(object_id)) {
+    RawOneByteString* str =
+        reinterpret_cast<RawOneByteString*>(Symbols::GetVMSymbol(object_id));
+    intptr_t len = Smi::Value(str->ptr()->length_);
+    Dart_CObject* object = AllocateDartCObjectString(len);
+    char* p = object->value.as_string;
+    memmove(p, str->ptr()->data_, len);
+    p[len] = '\0';
+    return object;
+  }
+  // No other VM isolate objects are supported.
+  return AllocateDartCObjectNull();
+}
+
+
 Dart_CObject* ApiMessageReader::ReadObjectRef() {
   int64_t value = Read<int64_t>();
   if ((value & kSmiTagMask) == 0) {
     int64_t untagged_value = value >> kSmiTagShift;
     if (kMinInt32 <= untagged_value && untagged_value <= kMaxInt32) {
       return AllocateDartCObjectInt32(untagged_value);
     } else {
       return AllocateDartCObjectInt64(untagged_value);
     }
   }
   ASSERT((value <= kIntptrMax) && (value >= kIntptrMin));
-  SerializedHeaderType header_type = SerializedHeaderTag::decode(value);
-  intptr_t header_value = SerializedHeaderData::decode(value);
-
-  if (header_type == kObjectId) {
-    return ReadIndexedObject(header_value);
+  if (IsVMIsolateObject(value)) {
+    intptr_t object_id = GetVMIsolateObjectId(value);
+    if (object_id == Object::kNullObject) {
+      return AllocateDartCObjectNull();
+    }
+    return ReadVMSymbol(object_id);
   }
-  ASSERT(header_type == kInlined);
+  if (SerializedHeaderTag::decode(value) == kObjectId) {
+    return ReadIndexedObject(SerializedHeaderData::decode(value));
+  }
+  ASSERT(SerializedHeaderTag::decode(value) == kInlined);
   // Read the class header information and lookup the class.
   intptr_t class_header = ReadIntptrValue();
 
   // Reading of regular dart instances is not supported.
   if (SerializedHeaderData::decode(class_header) == kInstanceId) {
     return AllocateDartCObjectUnsupported();
   }
   ASSERT((class_header & kSmiTagMask) != 0);
-  intptr_t object_id = header_value;
+  intptr_t object_id = SerializedHeaderData::decode(value);
   intptr_t class_id = LookupInternalClass(class_header);
   if (class_id == ObjectStore::kArrayClass ||
       class_id == ObjectStore::kImmutableArrayClass) {
     ASSERT(GetBackRef(object_id) == NULL);
     intptr_t len = ReadSmiValue();
     Dart_CObject* value = AllocateDartCObjectArray(len);
     AddBackRef(object_id, value, kIsNotDeserialized);
     return value;
   }
   intptr_t tags = ReadIntptrValue();
@@ skipping 102 matching lines @@
       return object;
     }
     default:
       // Everything else not supported.
       return AllocateDartCObjectUnsupported();
   }
 }
 
 
 Dart_CObject* ApiMessageReader::ReadIndexedObject(intptr_t object_id) {
-  if (object_id == Object::kNullObject) {
-    return AllocateDartCObjectNull();
-  }
   if (object_id == ObjectStore::kTrueValue) {
     return AllocateDartCObjectBool(true);
   }
   if (object_id == ObjectStore::kFalseValue) {
     return AllocateDartCObjectBool(false);
   }
   if (object_id == ObjectStore::kDynamicType ||
       object_id == ObjectStore::kDoubleInterface ||
       object_id == ObjectStore::kIntInterface ||
       object_id == ObjectStore::kBoolInterface ||
@@ skipping 24 matching lines @@
   int64_t value = Read<int64_t>();
   if ((value & kSmiTagMask) == 0) {
     int64_t untagged_value = value >> kSmiTagShift;
     if (kMinInt32 <= untagged_value && untagged_value <= kMaxInt32) {
       return AllocateDartCObjectInt32(untagged_value);
     } else {
       return AllocateDartCObjectInt64(untagged_value);
     }
   }
   ASSERT((value <= kIntptrMax) && (value >= kIntptrMin));
-  SerializedHeaderType header_type = SerializedHeaderTag::decode(value);
-  intptr_t header_value = SerializedHeaderData::decode(value);
-
-  if (header_type == kObjectId) {
-    return ReadIndexedObject(header_value);
+  if (IsVMIsolateObject(value)) {
+    intptr_t object_id = GetVMIsolateObjectId(value);
+    if (object_id == Object::kNullObject) {
+      return AllocateDartCObjectNull();
+    }
+    return ReadVMSymbol(object_id);
   }
-  ASSERT(header_type == kInlined);
-  return ReadInlinedObject(header_value);
+  if (SerializedHeaderTag::decode(value) == kObjectId) {
+    return ReadIndexedObject(SerializedHeaderData::decode(value));
+  }
+  ASSERT(SerializedHeaderTag::decode(value) == kInlined);
+  return ReadInlinedObject(SerializedHeaderData::decode(value));
 }
 
 
 void ApiMessageReader::AddBackRef(intptr_t id,
                                   Dart_CObject* obj,
                                   DeserializeState state) {
   intptr_t index = (id - kMaxPredefinedObjectIds);
   ASSERT(index == backward_references_.length());
   BackRefNode* node = AllocateBackRefNode(obj, state);
   ASSERT(node != NULL);
   backward_references_.Add(node);
 }
 
 
 Dart_CObject* ApiMessageReader::GetBackRef(intptr_t id) {
   ASSERT(id >= kMaxPredefinedObjectIds);
   intptr_t index = (id - kMaxPredefinedObjectIds);
   if (index < backward_references_.length()) {
     return backward_references_[index]->reference();
   }
   return NULL;
 }
 
 
 void ApiMessageWriter::WriteMessage(intptr_t field_count, intptr_t *data) {
   // Write out the serialization header value for this object.
-  WriteSerializationMarker(kInlined, kMaxPredefinedObjectIds);
+  WriteInlinedObjectHeader(kMaxPredefinedObjectIds);
 
   // Write out the class and tags information.
-  WriteObjectHeader(ObjectStore::kArrayClass, 0);
+  WriteIndexedObject(ObjectStore::kArrayClass);
+  WriteIntptrValue(0);
 
   // Write out the length field.
   Write<RawObject*>(Smi::New(field_count));
 
   // Write out the type arguments.
-  WriteIndexedObject(Object::kNullObject);
+  WriteNullObject();
 
   // Write out the individual Smis.
   for (int i = 0; i < field_count; i++) {
     Write<RawObject*>(Integer::New(data[i]));
   }
 
   FinalizeBuffer();
 }
 
 
@@ skipping 58 matching lines @@
   forward_id_ += 1;
 }
 
 
 void ApiMessageWriter::WriteSmi(int64_t value) {
   ASSERT(Smi::IsValid64(value));
   Write<RawObject*>(Smi::New(value));
 }
 
 
+void ApiMessageWriter::WriteNullObject() {
+  WriteVMIsolateObject(Object::kNullObject);
+}
+
+
 void ApiMessageWriter::WriteMint(Dart_CObject* object, int64_t value) {
   ASSERT(!Smi::IsValid64(value));
   // Write out the serialization header value for mint object.
   WriteInlinedHeader(object);
   // Write out the class and tags information.
-  WriteObjectHeader(ObjectStore::kMintClass, 0);
+  WriteIndexedObject(ObjectStore::kMintClass);
+  WriteIntptrValue(0);
   // Write the 64-bit value.
   Write<int64_t>(value);
 }
 
 
 void ApiMessageWriter::WriteInt32(Dart_CObject* object) {
   int64_t value = object->value.as_int32;
   if (Smi::IsValid64(value)) {
     WriteSmi(value);
   } else {
     WriteMint(object, value);
   }
 }
 
 
 void ApiMessageWriter::WriteInt64(Dart_CObject* object) {
   int64_t value = object->value.as_int64;
   if (Smi::IsValid64(value)) {
     WriteSmi(value);
   } else {
     WriteMint(object, value);
   }
 }
 
 
 void ApiMessageWriter::WriteInlinedHeader(Dart_CObject* object) {
   // Write out the serialization header value for this object.
-  WriteSerializationMarker(kInlined, kMaxPredefinedObjectIds + object_id_);
+  WriteInlinedObjectHeader(kMaxPredefinedObjectIds + object_id_);
   // Mark object with its object id.
   MarkCObject(object, object_id_);
   // Advance object id.
   object_id_++;
 }
 
 
 void ApiMessageWriter::WriteCObject(Dart_CObject* object) {
   if (IsCObjectMarked(object)) {
     intptr_t object_id = GetMarkedCObjectMark(object);
     WriteIndexedObject(kMaxPredefinedObjectIds + object_id);
     return;
   }
 
   Dart_CObject::Type type = object->type;
   if (type == Dart_CObject::kArray) {
     // Write out the serialization header value for this object.
     WriteInlinedHeader(object);
     // Write out the class and tags information.
-    WriteObjectHeader(ObjectStore::kArrayClass, 0);
+    WriteIndexedObject(ObjectStore::kArrayClass);
+    WriteIntptrValue(0);
+
     WriteSmi(object->value.as_array.length);
     // Write out the type arguments.
-    WriteIndexedObject(Object::kNullObject);
+    WriteNullObject();
     // Write out array elements.
     for (int i = 0; i < object->value.as_array.length; i++) {
       WriteCObjectRef(object->value.as_array.values[i]);
     }
     return;
   }
   return WriteCObjectInlined(object, type);
 }
 
 
@@ skipping 21 matching lines @@
 
 
 void ApiMessageWriter::WriteForwardedCObject(Dart_CObject* object) {
   ASSERT(IsCObjectMarked(object));
   Dart_CObject::Type type =
       static_cast<Dart_CObject::Type>(object->type & kDartCObjectTypeMask);
   ASSERT(type == Dart_CObject::kArray);
 
   // Write out the serialization header value for this object.
   intptr_t object_id = GetMarkedCObjectMark(object);
-  WriteSerializationMarker(kInlined, kMaxPredefinedObjectIds + object_id);
+  WriteInlinedObjectHeader(kMaxPredefinedObjectIds + object_id);
   // Write out the class and tags information.
-  WriteObjectHeader(ObjectStore::kArrayClass, 0);
+  WriteIndexedObject(ObjectStore::kArrayClass);
+  WriteIntptrValue(0);
+
   WriteSmi(object->value.as_array.length);
   // Write out the type arguments.
-  WriteIndexedObject(Object::kNullObject);
+  WriteNullObject();
   // Write out array elements.
   for (int i = 0; i < object->value.as_array.length; i++) {
     WriteCObjectRef(object->value.as_array.values[i]);
   }
 }
 
 
 void ApiMessageWriter::WriteCObjectInlined(Dart_CObject* object,
                                            Dart_CObject::Type type) {
   switch (type) {
     case Dart_CObject::kNull:
-      WriteIndexedObject(Object::kNullObject);
+      WriteNullObject();
       break;
     case Dart_CObject::kBool:
       if (object->value.as_bool) {
         WriteIndexedObject(ObjectStore::kTrueValue);
       } else {
         WriteIndexedObject(ObjectStore::kFalseValue);
       }
       break;
     case Dart_CObject::kInt32:
       WriteInt32(object);
       break;
     case Dart_CObject::kInt64:
       WriteInt64(object);
       break;
     case Dart_CObject::kBigint: {
       // Write out the serialization header value for this object.
       WriteInlinedHeader(object);
       // Write out the class and tags information.
-      WriteObjectHeader(ObjectStore::kBigintClass, 0);
+      WriteIndexedObject(ObjectStore::kBigintClass);
+      WriteIntptrValue(0);
       // Write hex string length and content
       char* hex_string = object->value.as_bigint;
       intptr_t len = strlen(hex_string);
       WriteIntptrValue(len);
       for (intptr_t i = 0; i < len; i++) {
         Write<uint8_t>(hex_string[i]);
       }
       break;
     }
     case Dart_CObject::kDouble:
       // Write out the serialization header value for this object.
       WriteInlinedHeader(object);
       // Write out the class and tags information.
-      WriteObjectHeader(ObjectStore::kDoubleClass, 0);
+      WriteIndexedObject(ObjectStore::kDoubleClass);
+      WriteIntptrValue(0);
       // Write double value.
       Write<double>(object->value.as_double);
       break;
     case Dart_CObject::kString: {
       // Write out the serialization header value for this object.
       WriteInlinedHeader(object);
       // Write out the class and tags information.
-      WriteObjectHeader(ObjectStore::kOneByteStringClass, 0);
+      WriteIndexedObject(ObjectStore::kOneByteStringClass);
+      WriteIntptrValue(0);
       // Write string length, hash and content
       char* str = object->value.as_string;
       intptr_t len = strlen(str);
       WriteSmi(len);
       WriteSmi(0);  // TODO(sgjesse): Hash - not written.
       for (intptr_t i = 0; i < len; i++) {
         Write<uint8_t>(str[i]);
       }
       break;
     }
     case Dart_CObject::kUint8Array: {
       // Write out the serialization header value for this object.
       WriteInlinedHeader(object);
       // Write out the class and tags information.
-      WriteObjectHeader(ObjectStore::kUint8ArrayClass, 0);
+      WriteIndexedObject(ObjectStore::kUint8ArrayClass);
+      WriteIntptrValue(0);
       uint8_t* bytes = object->value.as_byte_array.values;
       intptr_t len = object->value.as_byte_array.length;
       WriteSmi(len);
       for (intptr_t i = 0; i < len; i++) {
         Write<uint8_t>(bytes[i]);
       }
       break;
     }
     case Dart_CObject::kExternalUint8Array: {
       // TODO(ager): we are writing C pointers into the message in
       // order to post external arrays through ports. We need to make
       // sure that messages containing pointers can never be posted
       // to other processes.
 
       // Write out serialization header value for this object.
       WriteInlinedHeader(object);
       // Write out the class and tag information.
-      WriteObjectHeader(ObjectStore::kExternalUint8ArrayClass, 0);
+      WriteIndexedObject(ObjectStore::kExternalUint8ArrayClass);
+      WriteIntptrValue(0);
       int length = object->value.as_external_byte_array.length;
       uint8_t* data = object->value.as_external_byte_array.data;
       void* peer = object->value.as_external_byte_array.peer;
       Dart_PeerFinalizer callback =
           object->value.as_external_byte_array.callback;
       WriteSmi(length);
       WriteIntptrValue(reinterpret_cast<intptr_t>(data));
       WriteIntptrValue(reinterpret_cast<intptr_t>(peer));
       WriteIntptrValue(reinterpret_cast<intptr_t>(callback));
       break;
@@ skipping 10 matching lines @@
   // not been serialized yet. These would typically be fields of arrays.
   // NOTE: The forward list might grow as we process the list.
   for (intptr_t i = 0; i < forward_id_; i++) {
     WriteForwardedCObject(forward_list_[i]);
   }
   UnmarkAllCObjects(object);
   FinalizeBuffer();
 }
 
 }  // namespace dart