browsing_instance.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 CONTENT_BROWSER_BROWSING_INSTANCE_H_
#define CONTENT_BROWSER_BROWSING_INSTANCE_H_

#include <stddef.h>

#include <optional>

#include "base/check_op.h"
#include "base/gtest_prod_util.h"
#include "base/lazy_instance.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/ref_counted.h"
#include "content/browser/isolation_context.h"
#include "content/browser/security/coop/coop_related_group.h"
#include "content/browser/site_instance_group_manager.h"
#include "content/browser/web_exposed_isolation_info.h"
#include "content/common/content_export.h"
#include "content/public/browser/browser_context.h"
#include "content/public/browser/render_process_host_observer.h"
#include "content/public/browser/storage_partition_config.h"
#include "url/origin.h"

class GURL;

namespace content {
class SiteInfo;
class SiteInstanceGroup;
class SiteInstanceImpl;
struct UrlInfo;

///////////////////////////////////////////////////////////////////////////////
//
// BrowsingInstance class
//
// A browsing instance corresponds to the notion of a "unit of related browsing
// contexts" in the HTML 5 spec.  Intuitively, it represents a collection of
// tabs and frames that can have script connections to each other.  In that
// sense, it reflects the user interface, and not the contents of the tabs and
// frames.
//
// We further subdivide a BrowsingInstance into SiteInstances, which represent
// the documents within each BrowsingInstance that are from the same site and
// thus can have script access to each other.  Different SiteInstances can
// safely run in different processes, because their documents cannot access
// each other's contents (due to the same origin policy).
//
// It is important to only have one SiteInstance per site within a given
// BrowsingInstance.  This is because any two documents from the same site
// might be able to script each other if they are in the same BrowsingInstance.
// Thus, they must be rendered in the same process.
//
// A BrowsingInstance is live as long as any SiteInstance has a reference to
// it, and thus as long as any SiteInstanceGroup within it exists.  A
// SiteInstance is live as long as any NavigationEntry or RenderFrameHost have
// references to it.  Because both classes are RefCounted, they do not need to
// be manually deleted.
//
// BrowsingInstance has no public members, as it is designed to be
// visible only from the SiteInstance and CoopRelatedGroup classes. To get a new
// SiteInstance that is part of the same BrowsingInstance, use
// SiteInstance::GetRelatedSiteInstance. Because of this, BrowsingInstances and
// SiteInstances are tested together in site_instance_unittest.cc.
//
// Note that a browsing instance in the browser is independently tracked in
// the renderer inside blink::Page::RelatedPages() method (in theory the browser
// and renderer should always stay in sync).
//
///////////////////////////////////////////////////////////////////////////////
class CONTENT_EXPORT BrowsingInstance final
    : public base::RefCounted<BrowsingInstance> { … };

}  // namespace content

#endif  // CONTENT_BROWSER_BROWSING_INSTANCE_H_
chromium/content/browser/browsing_instance.h
