When an individual entry is lost from the appache's diskcache, attempts to load that resource will fallthru to the network instead of promptly failing. See bug 50657. This is just a first step, a repair step will follow on in a future change.

BUG=50657
TEST=none

Review URL: http://codereview.chromium.org/3187017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@57217 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 17 insertions, 5 deletions

diff --git a/webkit/appcache/appcache_request_handler.cc b/webkit/appcache/appcache_request_handler.cc
index 432534b..79f8909 100644
--- a/webkit/appcache/appcache_request_handler.cc
+++ b/webkit/appcache/appcache_request_handler.cc
@@ -53,7 +53,8 @@ AppCacheURLRequestJob* AppCacheRequestHandler::MaybeLoadResource(
   // which will call thru to our interception layer again.
   // This time thru, we return NULL so the request hits the wire.
   if (job_) {
-    DCHECK(job_->is_delivering_network_response());
+    DCHECK(job_->is_delivering_network_response() ||
+           job_->cache_entry_not_found());
     job_ = NULL;
     return NULL;
   }
diff --git a/webkit/appcache/appcache_url_request_job.cc b/webkit/appcache/appcache_url_request_job.cc
index b4be06a..50549e5 100644
--- a/webkit/appcache/appcache_url_request_job.cc
+++ b/webkit/appcache/appcache_url_request_job.cc
@@ -23,8 +23,8 @@ AppCacheURLRequestJob::AppCacheURLRequestJob(
     : URLRequestJob(request), storage_(storage),
       has_been_started_(false), has_been_killed_(false),
       delivery_type_(AWAITING_DELIVERY_ORDERS),
-      cache_id_(kNoCacheId),
-      is_fallback_(false),
+      cache_id_(kNoCacheId), is_fallback_(false),
+      cache_entry_not_found_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(read_callback_(
           this, &AppCacheURLRequestJob::OnReadComplete)) {
   DCHECK(storage_);
@@ -122,8 +122,13 @@ void AppCacheURLRequestJob::OnResponseInfoLoaded(
 
     NotifyHeadersComplete();
   } else {
-    NotifyStartError(
-        URLRequestStatus(URLRequestStatus::FAILED, net::ERR_FAILED));
+    // A resource that is expected to be in the appcache is missing.
+    // See http://code.google.com/p/chromium/issues/detail?id=50657
+    // Instead of failing the request, we restart the request. The retry
+    // attempt will fallthru to the network instead of trying to load
+    // from the appcache.
+    cache_entry_not_found_ = true;
+    NotifyRestartRequired();
   }
   storage_ = NULL;  // no longer needed
 }
diff --git a/webkit/appcache/appcache_url_request_job.h b/webkit/appcache/appcache_url_request_job.h
index 5e7dce2..8593ca1 100644
--- a/webkit/appcache/appcache_url_request_job.h
+++ b/webkit/appcache/appcache_url_request_job.h
@@ -69,6 +69,11 @@ class AppCacheURLRequestJob : public URLRequestJob,
     return has_been_killed_;
   }
 
+  // Returns true if the cache entry was not found in the disk cache.
+  bool cache_entry_not_found() const {
+    return cache_entry_not_found_;
+  }
+
  private:
   friend class AppCacheRequestHandlerTest;
   friend class AppCacheURLRequestJobTest;
@@ -132,6 +137,7 @@ class AppCacheURLRequestJob : public URLRequestJob,
   int64 cache_id_;
   AppCacheEntry entry_;
   bool is_fallback_;
+  bool cache_entry_not_found_;
   scoped_refptr<AppCacheResponseInfo> info_;
   net::HttpByteRange range_requested_;
   scoped_ptr<net::HttpResponseInfo> range_response_info_;