1 files changed, 149 insertions, 0 deletions
diff --git a/content/browser/browsing_instance.cc b/content/browser/browsing_instance.cc
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+++ b/content/browser/browsing_instance.cc
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+// Copyright (c) 2011 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.
+
+#include "content/browser/browsing_instance.h"
+
+#include "base/command_line.h"
+#include "base/logging.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/webui/web_ui_factory.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/common/url_constants.h"
+#include "content/browser/site_instance.h"
+
+// static
+BrowsingInstance::ProfileSiteInstanceMap
+    BrowsingInstance::profile_site_instance_map_;
+
+BrowsingInstance::BrowsingInstance(Profile* profile)
+    : profile_(profile) {
+}
+
+bool BrowsingInstance::ShouldUseProcessPerSite(const GURL& url) {
+  // Returns true if we should use the process-per-site model.  This will be
+  // the case if the --process-per-site switch is specified, or in
+  // process-per-site-instance for particular sites (e.g., the new tab page).
+
+  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
+  if (command_line.HasSwitch(switches::kProcessPerSite))
+    return true;
+
+  // We want to consolidate particular sites like extensions and WebUI whether
+  // it is in process-per-tab or process-per-site-instance.
+  // Note that --single-process may have been specified, but that affects the
+  // process creation logic in RenderProcessHost, so we do not need to worry
+  // about it here.
+
+  if (url.SchemeIs(chrome::kExtensionScheme))
+    return true;
+
+  // DevTools pages have WebUI type but should not reuse the same host.
+  if (WebUIFactory::UseWebUIForURL(profile_, url) &&
+      !url.SchemeIs(chrome::kChromeDevToolsScheme))
+    return true;
+
+  // In all other cases, don't use process-per-site logic.
+  return false;
+}
+
+BrowsingInstance::SiteInstanceMap* BrowsingInstance::GetSiteInstanceMap(
+    Profile* profile, const GURL& url) {
+  if (!ShouldUseProcessPerSite(SiteInstance::GetEffectiveURL(profile, url))) {
+    // Not using process-per-site, so use a map specific to this instance.
+    return &site_instance_map_;
+  }
+
+  // Otherwise, process-per-site is in use, at least for this URL.  Look up the
+  // global map for this profile, creating an entry if necessary.
+  ProfileId runtime_id = profile ? profile->GetRuntimeId()
+                                 : Profile::InvalidProfileId;
+  return &profile_site_instance_map_[runtime_id];
+}
+
+bool BrowsingInstance::HasSiteInstance(const GURL& url) {
+  std::string site =
+      SiteInstance::GetSiteForURL(profile_, url).possibly_invalid_spec();
+
+  SiteInstanceMap* map = GetSiteInstanceMap(profile_, url);
+  SiteInstanceMap::iterator i = map->find(site);
+  return (i != map->end());
+}
+
+SiteInstance* BrowsingInstance::GetSiteInstanceForURL(const GURL& url) {
+  std::string site =
+      SiteInstance::GetSiteForURL(profile_, url).possibly_invalid_spec();
+
+  SiteInstanceMap* map = GetSiteInstanceMap(profile_, url);
+  SiteInstanceMap::iterator i = map->find(site);
+  if (i != map->end()) {
+    return i->second;
+  }
+
+  // No current SiteInstance for this site, so let's create one.
+  SiteInstance* instance = new SiteInstance(this);
+
+  // Set the site of this new SiteInstance, which will register it with us.
+  instance->SetSite(url);
+  return instance;
+}
+
+void BrowsingInstance::RegisterSiteInstance(SiteInstance* site_instance) {
+  DCHECK(site_instance->browsing_instance() == this);
+  DCHECK(site_instance->has_site());
+  std::string site = site_instance->site().possibly_invalid_spec();
+
+  // Only register if we don't have a SiteInstance for this site already.
+  // It's possible to have two SiteInstances point to the same site if two
+  // tabs are navigated there at the same time.  (We don't call SetSite or
+  // register them until DidNavigate.)  If there is a previously existing
+  // SiteInstance for this site, we just won't register the new one.
+  SiteInstanceMap* map = GetSiteInstanceMap(profile_, site_instance->site());
+  SiteInstanceMap::iterator i = map->find(site);
+  if (i == map->end()) {
+    // Not previously registered, so register it.
+    (*map)[site] = site_instance;
+  }
+}
+
+void BrowsingInstance::UnregisterSiteInstance(SiteInstance* site_instance) {
+  DCHECK(site_instance->browsing_instance() == this);
+  DCHECK(site_instance->has_site());
+  std::string site = site_instance->site().possibly_invalid_spec();
+
+  // Only unregister the SiteInstance if it is the same one that is registered
+  // for the site.  (It might have been an unregistered SiteInstance.  See the
+  // comments in RegisterSiteInstance.)
+
+  // We look for the site instance in both the local site_instance_map_ and also
+  // the static profile_site_instance_map_ - this is because the logic in
+  // ShouldUseProcessPerSite() can produce different results over the lifetime
+  // of Chrome (e.g. installation of apps with web extents can change our
+  // process-per-site policy for a given domain), so we don't know which map
+  // the site was put into when it was originally registered.
+  if (!RemoveSiteInstanceFromMap(&site_instance_map_, site, site_instance)) {
+    // Wasn't in our local map, so look in the static per-profile map.
+    ProfileId runtime_id = profile_ ? profile_->GetRuntimeId()
+                                    : Profile::InvalidProfileId;
+    RemoveSiteInstanceFromMap(
+        &profile_site_instance_map_[runtime_id], site, site_instance);
+  }
+}
+
+bool BrowsingInstance::RemoveSiteInstanceFromMap(SiteInstanceMap* map,
+                                                 const std::string& site,
+                                                 SiteInstance* site_instance) {
+  SiteInstanceMap::iterator i = map->find(site);
+  if (i != map->end() && i->second == site_instance) {
+    // Matches, so erase it.
+    map->erase(i);
+    return true;
+  }
+  return false;
+}
+
+BrowsingInstance::~BrowsingInstance() {
+  // We should only be deleted when all of the SiteInstances that refer to
+  // us are gone.
+  DCHECK(site_instance_map_.empty());
+}