1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifndef CONTENT_PUBLIC_BROWSER_HISTOGRAM_FETCHER_H_
6 #define CONTENT_PUBLIC_BROWSER_HISTOGRAM_FETCHER_H_
7 
8 #include "base/callback.h"
9 #include "base/task_runner.h"
10 #include "base/time/time.h"
11 #include "content/common/content_export.h"
12 
13 namespace content {
14 
15 // Fetch histogram data asynchronously from the various child processes, into
16 // the browser process. This method is used by the metrics services in
17 // preparation for a log upload. It contacts all processes, and get them to
18 // upload to the browser any/all changes to histograms.  When all changes have
19 // been acquired, or when the wait time expires (whichever is sooner), post the
20 // callback to the specified TaskRunner. Note the callback is posted exactly
21 // once.
22 CONTENT_EXPORT void FetchHistogramsAsynchronously(
23     scoped_refptr<base::TaskRunner> task_runner,
24     base::OnceClosure callback,
25     base::TimeDelta wait_time);
26 
27 }  // namespace content
28 
29 #endif  // CONTENT_PUBLIC_BROWSER_HISTOGRAM_FETCHER_H_
30