Create base::WorkerPoolJob. Use it for HostResolverImpl and DirectoryLister.

net/base/directory_lister.h

 // Copyright (c) 2010 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 NET_BASE_DIRECTORY_LISTER_H_
 #define NET_BASE_DIRECTORY_LISTER_H_
 #pragma once
 
-#include <vector>
-
-#include "base/cancellation_flag.h"
+#include "base/basictypes.h"
 #include "base/file_path.h"
 #include "base/file_util.h"
-#include "base/platform_thread.h"
 #include "base/ref_counted.h"
-#include "base/task.h"
-
-class MessageLoop;
+#include "base/worker_pool_job.h"
 
 namespace net {
 
-//
 // This class provides an API for listing the contents of a directory on the
 // filesystem asynchronously.  It spawns a background thread, and enumerates
 // the specified directory on that thread.  It marshalls WIN32_FIND_DATA
 // structs over to the main application thread.  The consumer of this class
 // is insulated from any of the multi-threading details.
 //
-class DirectoryLister : public base::RefCountedThreadSafe<DirectoryLister>,
-                        public PlatformThread::Delegate {
+class DirectoryLister {
  public:
   // Represents one file found.
-  struct DirectoryListerData {
+  struct Data {
     file_util::FileEnumerator::FindInfo info;
     FilePath path;
   };
 
   // Implement this class to receive directory entries.
-  class DirectoryListerDelegate {
+  class Delegate {
    public:
     // Called for each file found by the lister.
-    virtual void OnListFile(const DirectoryListerData& data) = 0;
+    virtual void OnListFile(const Data& data) = 0;
 
-    // Called when the listing is complete.
+    // Called when the listing is complete.  May not be called if Cancel() is
+    // called.
     virtual void OnListDone(int error) = 0;
 
    protected:
-    virtual ~DirectoryListerDelegate() {}
+    virtual ~Delegate() {}
   };
 
   // Sort options
   // ALPHA_DIRS_FIRST is the default sort :
   //   directories first in name order, then files by name order
   // FULL_PATH sorts by paths as strings, ignoring files v. directories
   // DATE sorts by last modified date
   enum SORT_TYPE {
     NO_SORT,
     DATE,
     ALPHA_DIRS_FIRST,
     FULL_PATH
   };
 
-  DirectoryLister(const FilePath& dir,
-                  DirectoryListerDelegate* delegate);
+  DirectoryLister(const FilePath& dir, Delegate* delegate);
 
   DirectoryLister(const FilePath& dir,
                   bool recursive,
                   SORT_TYPE sort,
-                  DirectoryListerDelegate* delegate);
-
+                  Delegate* delegate);
+  ~DirectoryLister();
 
   // Call this method to start the directory enumeration thread.
-  bool Start();
+  void Start();
 
-  // Call this method to asynchronously stop directory enumeration.  The
-  // delegate will receive the OnListDone notification with an error code of
-  // net::ERR_ABORTED.
+  // Only valid to call this after Start() is called, and before
+  // Delegate::OnListDone() is invoked.
   void Cancel();
 
-  // The delegate pointer may be modified at any time.
-  DirectoryListerDelegate* delegate() const { return delegate_; }
-  void set_delegate(DirectoryListerDelegate* d) { delegate_ = d; }
-
-  // PlatformThread::Delegate implementation
-  virtual void ThreadMain();
+  // Blocks on DirectoryLister until the worker job finishes on the
+  // WorkerPoolThread or is otherwise canceled.  This is useful for testing, and
+  // possibly useful in case callers want to block on DirectoryLister
+  // completion, although this is not advised for latency critical threads.
+  void WaitUntilDone();
 
  private:
-  friend class base::RefCountedThreadSafe<DirectoryLister>;
-  friend class DirectoryDataEvent;
+  class Job;
 
-  // Comparison methods for sorting, chosen based on |sort_|.
-  static bool CompareAlphaDirsFirst(const DirectoryListerData& a,
-                                    const DirectoryListerData& b);
-  static bool CompareDate(const DirectoryListerData& a,
-                          const DirectoryListerData& b);
-  static bool CompareFullPath(const DirectoryListerData& a,
-                              const DirectoryListerData& b);
+  base::WorkerPoolJob::ScopedHandle<Job> job_handle_;
 
-  ~DirectoryLister();
-
-  void OnReceivedData(const DirectoryListerData* data, int count);
-  void OnDone(int error);
-
-  FilePath dir_;
-  bool recursive_;
-  DirectoryListerDelegate* delegate_;
-  SORT_TYPE sort_;
-  MessageLoop* message_loop_;
-  PlatformThreadHandle thread_;
-  base::CancellationFlag canceled_;
+  DISALLOW_COPY_AND_ASSIGN(DirectoryLister);
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_DIRECTORY_LISTER_H_