Add Service ID zones to service protocol

runtime/vm/service.h

 // Copyright (c) 2013, 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.
 
 #ifndef VM_SERVICE_H_
 #define VM_SERVICE_H_
 
 #include "include/dart_api.h"
 
 #include "vm/allocation.h"
+#include "vm/object_id_ring.h"
 #include "vm/os_thread.h"
 
 namespace dart {
 
 class Array;
 class EmbedderServiceHandler;
 class GCEvent;
+class GrowableObjectArray;
 class Instance;
 class Isolate;
 class JSONStream;
 class Object;
 class RawInstance;
 class ServiceEvent;
 class String;
 
+class ServiceIdZone {
+ public:
+  ServiceIdZone();
+  virtual ~ServiceIdZone();
+
+  // Returned string will be zone allocated.
+  virtual char* GetServiceId(const Object& obj) = 0;
+
+ private:
+};
+
+
+class RingServiceIdZone : public ServiceIdZone {
+ public:
+  // Use the isolate's object id ring.
+  explicit RingServiceIdZone(ObjectIdRing::IdPolicy policy);
+  virtual ~RingServiceIdZone();
+
+  // Returned string will be zone allocated.
+  virtual char* GetServiceId(const Object& obj);
+
+ private:
+  ObjectIdRing::IdPolicy policy_;
+};
+
+
+// Growable array of objects. Ids are derived from the format string passed in
+// and the index into the storage array. Ids are always reused to avoid growing
+// the array.
+class GrowableServiceIdZone : public ServiceIdZone {
+ public:
+  // |format_str| must contain one and only one format specifier (%" Pd "). It
+  // will be replaced with the index into the array. |storage| can not be null.
+  GrowableServiceIdZone(const char* format_str,
+                        const GrowableObjectArray& storage);
+  virtual ~GrowableServiceIdZone();
+
+  // Returned string will be zone allocated.
+  virtual char* GetServiceId(const Object& obj);
+
+ private:
+  intptr_t FindIndex(const Object& obj);
+  intptr_t Append(const Object& obj);
+
+  const char* format_str_;
+  const GrowableObjectArray& array_;
+};
+
+
 class Service : public AllStatic {
  public:
   // Handles a message which is not directed to an isolate.
   static void HandleRootMessage(const Array& message);
 
   // Handles a message which is directed to a particular isolate.
   static void HandleIsolateMessage(Isolate* isolate, const Array& message);
 
   static bool NeedsEvents();
 
@@ skipping 29 matching lines @@
                         const uint8_t* data,
                         intptr_t size);
 
   static EmbedderServiceHandler* isolate_service_handler_head_;
   static EmbedderServiceHandler* root_service_handler_head_;
 };
 
 }  // namespace dart
 
 #endif  // VM_SERVICE_H_