Defend against selectCache() being called multiple times....

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"
@@ skipping 54 matching lines @@
 
 WebApplicationCacheHostImpl::WebApplicationCacheHostImpl(
     WebApplicationCacheHostClient* client,
     AppCacheBackend* backend)
     : client_(client),
       backend_(backend),
       ALLOW_THIS_IN_INITIALIZER_LIST(host_id_(g_hosts_map.Get().Add(this))),
       status_(UNCACHED),
       is_scheme_supported_(false),
       is_get_method_(false),
-      is_new_master_entry_(MAYBE) {
+      is_new_master_entry_(MAYBE),
+      was_select_cache_called_(false) {
   DCHECK(client && backend && (host_id_ != kNoHostId));
 
   backend_->RegisterHost(host_id_);
 }
 
 WebApplicationCacheHostImpl::~WebApplicationCacheHostImpl() {
   backend_->UnregisterHost(host_id_);
   g_hosts_map.Get().Remove(host_id_);
 }
 
@@ skipping 78 matching lines @@
   is_get_method_ = (method == kHttpGETMethod);
   DCHECK(method == StringToUpperASCII(method));
 }
 
 void WebApplicationCacheHostImpl::willStartSubResourceRequest(
     WebURLRequest& request) {
   request.setAppCacheHostID(host_id_);
 }
 
 void WebApplicationCacheHostImpl::selectCacheWithoutManifest() {
+  if (was_select_cache_called_)
+    return;
+  was_select_cache_called_ = true;
+
   status_ = (document_response_.appCacheID() == kNoCacheId) ?
       UNCACHED : CHECKING;
   is_new_master_entry_ = NO;
   backend_->SelectCache(host_id_, document_url_,
                         document_response_.appCacheID(),
                         GURL());
 }
 
 bool WebApplicationCacheHostImpl::selectCacheWithManifest(
     const WebURL& manifest_url) {
+  if (was_select_cache_called_)
+    return true;
+  was_select_cache_called_ = true;
+
   GURL manifest_gurl(ClearUrlRef(manifest_url));
 
   // 6.9.6 The application cache selection algorithm
   // Check for new 'master' entries.
   if (document_response_.appCacheID() == kNoCacheId) {
     if (is_scheme_supported_ && is_get_method_ &&
         (manifest_gurl.GetOrigin() == document_url_.GetOrigin())) {
       status_ = CHECKING;
       is_new_master_entry_ = YES;
     } else {
@@ skipping 99 matching lines @@
     web_resources[i].isExplicit = resource_infos[i].is_explicit;
     web_resources[i].isManifest = resource_infos[i].is_manifest;
     web_resources[i].isForeign = resource_infos[i].is_foreign;
     web_resources[i].isFallback = resource_infos[i].is_fallback;
     web_resources[i].url = resource_infos[i].url;
   }
   resources->swap(web_resources);
 }
 
 }  // appcache namespace