Initial prototype of vmstats support, based on Dart VM Stats draft design doc.

runtime/bin/vmstats_impl.h

Index: runtime/bin/vmstats_impl.h
===================================================================
--- runtime/bin/vmstats_impl.h	(revision 0)
+++ runtime/bin/vmstats_impl.h	(revision 0)
@@ -0,0 +1,99 @@
+// 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 BIN_VMSTATS_IMPL_H_
+#define BIN_VMSTATS_IMPL_H_
+
+#include "bin/vmstats.h"
+
+#include <map>
+#include <sstream>
+#include <string>
+
+#include "bin/isolate_data.h"
+#include "platform/thread.h"
+
+// VmStats is a HTTP singleton service that reports status information
+// of the running VM.
+
+class VmStats {
+ public:
+  static void Start(int port, const char* root_dir);
+  static void Stop();
+
+  // Add and remove functions for the isolate_table, called by main.cc.
+  static void AddIsolate(IsolateData* isolate_data, Dart_Isolate isolate);
+  static void RemoveIsolate(IsolateData* isolate_data);
+
+ private:
+  VmStats() : running_(false), bind_address_(0) {}
+
+  static void WebServer(uword bind_address);
+  static void Shutdown();
+
+  // Status text generators.
+  char* IsolatesStatus();
+
+  typedef std::map<IsolateData*, Dart_Isolate> IsolateTable;
+
+  std::string root_directory_;
+  IsolateTable isolate_table_;
+  bool running_;
+  int64_t bind_address_;
+
+  static VmStats* instance_;
+  static dart::Monitor instance_monitor_;
+
+  // Disallow copy constructor.
+  DISALLOW_COPY_AND_ASSIGN(VmStats);
+};
+
+
+// Status plug-in and linked-list node.
+class VmStatusPlugin {
+ public:
+  explicit VmStatusPlugin(Dart_VmStatusCallback callback)
+      : callback_(callback), next_(NULL) {}
+
+  void Append(VmStatusPlugin* plugin) {
+    VmStatusPlugin* list = this;
+    while (list->next_ != NULL) {
+      list = list->next_;
+    }
+    list->next_ = plugin;
+  }
+
+  Dart_VmStatusCallback callback() { return callback_; }
+  VmStatusPlugin* next() { return next_; }
+
+ private:
+  Dart_VmStatusCallback callback_;
+  VmStatusPlugin* next_;
+};
+
+
+// Singleton service managing VM status gathering and status plug-in
+// registration.
+class VmStatusService {
+ public:
+  static int RegisterPlugin(Dart_VmStatusCallback callback);
+
+  // Returns VM status for a specified request. The caller is responsible
+  // for releasing the heap memory after use.
+  static char* GetVmStatus(const char* request);
+
+  static void InitOnce();
+
+ private:
+  VmStatusService() : registered_plugin_list_(NULL) {}
+
+  static VmStatusService* instance_;
+  static dart::Mutex mutex_;
+
+  VmStatusPlugin* registered_plugin_list_;
+
+  DISALLOW_COPY_AND_ASSIGN(VmStatusService);
+};
+
+#endif  // BIN_VMSTATS_IMPL_H_