text: // Copyright (c) 2012 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #ifndef CONTENT_BROWSER_WORKER_HOST_WORKER_SERVICE_H_
  #define CONTENT_BROWSER_WORKER_HOST_WORKER_SERVICE_H_
  
  #include "base/basictypes.h"
  #include "base/compiler_specific.h"
  #include "base/memory/singleton.h"
  #include "base/observer_list.h"
  #include "base/threading/non_thread_safe.h"
  #include "content/browser/worker_host/worker_process_host.h"
  #include "content/public/browser/notification_observer.h"
  #include "content/public/browser/notification_registrar.h"
  #include "content/public/browser/worker_service.h"
  
  class GURL;
  struct ViewHostMsg_CreateWorker_Params;
  
  namespace content {
  class ResourceContext;
  class WorkerServiceObserver;
  class WorkerStoragePartition;
  class WorkerPrioritySetter;
  
  class CONTENT_EXPORT WorkerServiceImpl
      : public NON_EXPORTED_BASE(WorkerService) {
   public:
    // Returns the WorkerServiceImpl singleton.
    static WorkerServiceImpl* GetInstance();
  
    // Releases the priority setter to avoid memory leak error.
    void PerformTeardownForTesting();
  
    // WorkerService implementation:
    virtual bool TerminateWorker(int process_id, int route_id) OVERRIDE;
    virtual std::vector<WorkerInfo> GetWorkers() OVERRIDE;
    virtual void AddObserver(WorkerServiceObserver* observer) OVERRIDE;
    virtual void RemoveObserver(WorkerServiceObserver* observer) OVERRIDE;
  
    // These methods correspond to worker related IPCs.
    void CreateWorker(const ViewHostMsg_CreateWorker_Params& params,
                      int route_id,
                      WorkerMessageFilter* filter,
                      ResourceContext* resource_context,
                      const WorkerStoragePartition& worker_partition);
    void LookupSharedWorker(const ViewHostMsg_CreateWorker_Params& params,
                            int route_id,
                            WorkerMessageFilter* filter,
                            ResourceContext* resource_context,
                            const WorkerStoragePartition& worker_partition,
                            bool* exists,
                            bool* url_error);
    void CancelCreateDedicatedWorker(int route_id, WorkerMessageFilter* filter);
    void ForwardToWorker(const IPC::Message& message,
                         WorkerMessageFilter* filter);
    void DocumentDetached(unsigned long long document_id,
                          WorkerMessageFilter* filter);
  
    void OnWorkerMessageFilterClosing(WorkerMessageFilter* filter);
  
    int next_worker_route_id() { return ++next_worker_route_id_; }
  
    // Given a worker's process id, return the IDs of the renderer process and
    // render view that created it.  For shared workers, this returns the first
    // parent.
    // TODO(dimich): This code assumes there is 1 worker per worker process, which
    // is how it is today until V8 can run in separate threads.
    bool GetRendererForWorker(int worker_process_id,
                              int* render_process_id,
                              int* render_view_id) const;
    const WorkerProcessHost::WorkerInstance* FindWorkerInstance(
        int worker_process_id);
  
    void NotifyWorkerDestroyed(
        WorkerProcessHost* process,
        int worker_route_id);
  
    void NotifyWorkerProcessCreated();
  
    // Used when we run each worker in a separate process.
    static const int kMaxWorkersWhenSeparate;
    static const int kMaxWorkersPerTabWhenSeparate;
  
   private:
    friend struct DefaultSingletonTraits<WorkerServiceImpl>;
  
    WorkerServiceImpl();
    virtual ~WorkerServiceImpl();
  
    // Given a WorkerInstance, create an associated worker process.
    bool CreateWorkerFromInstance(WorkerProcessHost::WorkerInstance instance);
  
    // Checks if we can create a worker process based on the process limit when
    // we're using a strategy of one process per core.
    bool CanCreateWorkerProcess(
        const WorkerProcessHost::WorkerInstance& instance);
  
    // Checks if the tab associated with the passed RenderView can create a
    // worker process based on the process limit when we're using a strategy of
    // one worker per process.
    bool TabCanCreateWorkerProcess(
        int render_process_id, int render_route_id, bool* hit_total_worker_limit);
  
    // Tries to see if any of the queued workers can be created.
    void TryStartingQueuedWorker();
  
    // APIs for manipulating our set of pending shared worker instances.
    WorkerProcessHost::WorkerInstance* CreatePendingInstance(
        const GURL& url,
        const string16& name,
        ResourceContext* resource_context,
        const WorkerStoragePartition& worker_partition);
    WorkerProcessHost::WorkerInstance* FindPendingInstance(
        const GURL& url,
        const string16& name,
        const WorkerStoragePartition& worker_partition,
        ResourceContext* resource_context);
    void RemovePendingInstances(
        const GURL& url,
        const string16& name,
        const WorkerStoragePartition& worker_partition,
        ResourceContext* resource_context);
  
    WorkerProcessHost::WorkerInstance* FindSharedWorkerInstance(
        const GURL& url,
        const string16& name,
        const WorkerStoragePartition& worker_partition,
        ResourceContext* resource_context);
  
    scoped_refptr<WorkerPrioritySetter> priority_setter_;
  
    int next_worker_route_id_;
  
    WorkerProcessHost::Instances queued_workers_;
  
    // These are shared workers that have been looked up, but not created yet.
    // We need to keep a list of these to synchronously detect shared worker
    // URL mismatches when two pages launch shared workers simultaneously.
    WorkerProcessHost::Instances pending_shared_workers_;
  
    ObserverList<WorkerServiceObserver> observers_;
  
    DISALLOW_COPY_AND_ASSIGN(WorkerServiceImpl);
  };
  
  }  // namespace content
  
  #endif  // CONTENT_BROWSER_WORKER_HOST_WORKER_SERVICE_H_
  