Make members of Singleton<T> private and only visible to the singleton type.

webkit/appcache/web_application_cache_host_impl.cc

 // 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.
 
 #include "webkit/appcache/web_application_cache_host_impl.h"
 
 #include "base/compiler_specific.h"
 #include "base/id_map.h"
+#include "base/lazy_instance.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
-#include "base/singleton.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebDataSource.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebFrame.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebURL.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebURLRequest.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebURLResponse.h"
 
 using WebKit::WebApplicationCacheHost;
 using WebKit::WebApplicationCacheHostClient;
 using WebKit::WebDataSource;
 using WebKit::WebFrame;
 using WebKit::WebURLRequest;
 using WebKit::WebURL;
 using WebKit::WebURLResponse;
 using WebKit::WebVector;
 
 namespace appcache {
 
 namespace {
 
 typedef IDMap<WebApplicationCacheHostImpl> HostsMap;
+static base::LazyInstance<HostsMap> g_hosts_map(base::LINKER_INITIALIZED);
 
 // Note: the order of the elements in this array must match those
 // of the EventID enum in appcache_interfaces.h.
 const char* kEventNames[] = {
   "Checking", "Error", "NoUpdate", "Downloading", "Progress",
   "UpdateReady", "Cached", "Obsolete"
 };
 
 GURL ClearUrlRef(const GURL& url) {
   if (!url.has_ref())
     return url;
   GURL::Replacements replacements;
   replacements.ClearRef();
   return url.ReplaceComponents(replacements);
 }
 
-HostsMap* all_hosts() {
-  return Singleton<HostsMap>::get();
-}
-
 }  // anon namespace
 
 WebApplicationCacheHostImpl* WebApplicationCacheHostImpl::FromId(int id) {
-  return all_hosts()->Lookup(id);
+  return g_hosts_map.Get().Lookup(id);
 }
 
 WebApplicationCacheHostImpl* WebApplicationCacheHostImpl::FromFrame(
     WebFrame* frame) {
   if (!frame)
     return NULL;
   WebDataSource* data_source = frame->dataSource();
   if (!data_source)
     return NULL;
   return static_cast<WebApplicationCacheHostImpl*>
       (data_source->applicationCacheHost());
 }
 
 WebApplicationCacheHostImpl::WebApplicationCacheHostImpl(
     WebApplicationCacheHostClient* client,
     AppCacheBackend* backend)
     : client_(client),
       backend_(backend),
-      ALLOW_THIS_IN_INITIALIZER_LIST(host_id_(all_hosts()->Add(this))),
+      ALLOW_THIS_IN_INITIALIZER_LIST(host_id_(g_hosts_map.Get().Add(this))),
       has_status_(false),
       status_(UNCACHED),
       has_cached_status_(false),
       cached_status_(UNCACHED),
       is_scheme_supported_(false),
       is_get_method_(false),
       is_new_master_entry_(MAYBE) {
   DCHECK(client && backend && (host_id_ != kNoHostId));
 
   backend_->RegisterHost(host_id_);
 }
 
 WebApplicationCacheHostImpl::~WebApplicationCacheHostImpl() {
   backend_->UnregisterHost(host_id_);
-  all_hosts()->Remove(host_id_);
+  g_hosts_map.Get().Remove(host_id_);
 }
 
 void WebApplicationCacheHostImpl::OnCacheSelected(
     const appcache::AppCacheInfo& info) {
   status_ = info.status;
   has_status_ = true;
   cache_info_ = info;
   client_->didChangeCacheAssociation();
 }
 
@@ skipping 210 matching lines @@
 
 bool WebApplicationCacheHostImpl::swapCache() {
   // Cache status will change when cache is swapped. Clear out any saved idea
   // of status so that backend will be queried for actual status.
   has_status_ = false;
   has_cached_status_ = false;
   return backend_->SwapCache(host_id_);
 }
 
 }  // appcache namespace