download_request_limiter.h | Explore in Territory

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CHROME_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_LIMITER_H_
#define CHROME_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_LIMITER_H_

#include <stddef.h>

#include <map>
#include <set>
#include <string>
#include <vector>

#include "base/functional/callback.h"
#include "base/gtest_prod_util.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/scoped_observation.h"
#include "components/content_settings/core/browser/content_settings_observer.h"
#include "components/content_settings/core/browser/host_content_settings_map.h"
#include "components/content_settings/core/common/content_settings.h"
#include "content/public/browser/web_contents.h"
#include "content/public/browser/web_contents_observer.h"
#include "url/origin.h"

namespace content {
class WebContents;
}

// DownloadRequestLimiter is responsible for determining whether a download
// should be allowed or not. It is designed to keep pages from downloading
// multiple files without user interaction. DownloadRequestLimiter is invoked
// from ResourceDispatcherHost any time a download begins
// (CanDownload). The request is processed on the UI thread, and the
// request is notified (back on the IO thread) as to whether the download should
// be allowed or denied.
//
// Invoking CanDownload notifies the callback and may update the
// download status. The following details the various states:
// . Each NavigationController initially starts out allowing a download
//   (ALLOW_ONE_DOWNLOAD).
// . The first time CanDownload is invoked the download is allowed and
//   the state changes to PROMPT_BEFORE_DOWNLOAD.
// . If the state is PROMPT_BEFORE_DOWNLOAD and the user clicks the mouse,
//   presses enter, the space bar or navigates to another page the state is
//   reset to ALLOW_ONE_DOWNLOAD.
// . If a download is attempted and the state is PROMPT_BEFORE_DOWNLOAD the user
//   is prompted as to whether the download is allowed or disallowed. The users
//   choice stays until the user navigates to a different host. For example, if
//   the user allowed the download, multiple downloads are allowed without any
//   user intervention until the user navigates to a different host.
//
// The DownloadUiStatus indicates whether omnibox UI should be shown for the
// current download status. We do not show UI if there has not yet been
// a download attempt on the page regardless of the internal download status.
class DownloadRequestLimiter
    : public base::RefCountedThreadSafe<DownloadRequestLimiter> { … };

#endif  // CHROME_BROWSER_DOWNLOAD_DOWNLOAD_REQUEST_LIMITER_H_
chromium/chrome/browser/download/download_request_limiter.h
