Revert of This is a reland of ServiceWorkerCache::Keys. (patchset #3 id:70001 of https://codereview.chromium.org/528233003/)

Reason for revert:
Now getting a Valgrind leak that is likely due to this CL:

Suppression (error hash=#935FB14CBC8B5858#):
For more info on using suppressions see http://dev.chromium.org/developers/tree-sheriffs/sheriff-details-chromium/memory-sheriff#TOC-Suppressing-memory-reports
{
<insert_a_suppression_name_here>
Memcheck:Leak
fun:_Znw*
fun:_ZN9__gnu_cxx13new_allocatorIN10disk_cache20SimpleEntryOperationEE8allocateEmPKv
fun:_ZNSt11_Deque_baseIN10disk_cache20SimpleEntryOperationESaIS1_EE16_M_allocate_nodeEv
fun:_ZNSt5dequeIN10disk_cache20SimpleEntryOperationESaIS1_EE16_M_push_back_auxIJS1_EEEvDpOT_
fun:_ZNSt5dequeIN10disk_cache20SimpleEntryOperationESaIS1_EE12emplace_backIJS1_EEEvDpOT_
fun:_ZNSt5dequeIN10disk_cache20SimpleEntryOperationESaIS1_EE9push_backEOS1_
fun:_ZNSt5queueIN10disk_cache20SimpleEntryOperationESt5dequeIS1_SaIS1_EEE4pushEOS1_
fun:_ZN10disk_cache15SimpleEntryImpl5CloseEv
fun:_ZN10disk_cache12EntryDeleterclEPNS_5EntryE
fun:_ZN4base8internal15scoped_ptr_implIN10disk_cache5EntryENS2_12EntryDeleterEED2Ev
fun:_ZN10scoped_ptrIN10disk_cache5EntryENS0_12EntryDeleterEED2Ev
}

Original issue's description:
> This is a reland of ServiceWorkerCache::Keys.
>
> Reland of https://codereview.chromium.org/477973002/
>
> There was a memory leak.  EndEnumeration wasn't called on the iterator.
>
> Fixed and tested with ASAN.
>
> The leak was detected because SimpleCache doesn't clean up its enumerators on deletion, but it should.  See https://code.google.com/p/chromium/issues/detail?id=410276
>
> BUG=392621
>
> Committed: https://chromium.googlesource.com/chromium/src/+/a3a3703b91203db3e2248d656b86cb26bf2e30e3

TBR=michaeln@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=392621

Review URL: https://codereview.chromium.org/538263002

Cr-Commit-Position: refs/heads/master@{#293373}

1 files changed, 37 insertions, 212 deletions

diff --git a/content/browser/service_worker/service_worker_cache.cc b/content/browser/service_worker/service_worker_cache.cc
index 12a0e8b..c2cfe64 100644
--- a/content/browser/service_worker/service_worker_cache.cc
+++ b/content/browser/service_worker/service_worker_cache.cc
@@ -27,9 +27,6 @@ typedef scoped_ptr<disk_cache::Backend> ScopedBackendPtr;
 typedef base::Callback<void(bool)> BoolCallback;
 typedef base::Callback<void(disk_cache::ScopedEntryPtr, bool)>
     EntryBoolCallback;
-typedef base::Callback<void(scoped_ptr<ServiceWorkerRequestResponseHeaders>)>
-    HeadersCallback;
-
 enum EntryIndex { INDEX_HEADERS = 0, INDEX_RESPONSE_BODY };
 
 // The maximum size of an individual cache. Ultimately cache size is controlled
@@ -192,7 +189,8 @@ void MatchDidReadHeaderData(
     const ServiceWorkerCache::ResponseCallback& callback,
     base::WeakPtr<storage::BlobStorageContext> blob_storage,
     disk_cache::ScopedEntryPtr entry,
-    scoped_ptr<ServiceWorkerRequestResponseHeaders> headers);
+    const scoped_refptr<net::IOBufferWithSize>& buffer,
+    int rv);
 void MatchDidReadResponseBodyData(
     ServiceWorkerFetchRequest* request,
     const ServiceWorkerCache::ResponseCallback& callback,
@@ -213,15 +211,6 @@ void DeleteDidOpenEntry(ServiceWorkerFetchRequest* request,
                         scoped_ptr<disk_cache::Entry*> entryptr,
                         int rv);
 
-// Copy headers out of a cache entry and into a protobuf. The callback is
-// guaranteed to be run.
-void ReadHeaders(disk_cache::Entry* entry, const HeadersCallback& callback);
-void ReadHeadersDidReadHeaderData(
-    disk_cache::Entry* entry,
-    const HeadersCallback& callback,
-    const scoped_refptr<net::IOBufferWithSize>& buffer,
-    int rv);
-
 // CreateBackend callbacks
 void CreateBackendDidCreate(const ServiceWorkerCache::ErrorCallback& callback,
                             scoped_ptr<ScopedBackendPtr> backend_ptr,
@@ -361,16 +350,25 @@ void MatchDidOpenEntry(ServiceWorkerFetchRequest* request,
   DCHECK(entryptr);
   disk_cache::ScopedEntryPtr entry(*entryptr);
 
+  scoped_refptr<net::IOBufferWithSize> buffer(
+      new net::IOBufferWithSize(entry->GetDataSize(INDEX_HEADERS)));
+
   // Copy the entry pointer before passing it in base::Bind.
   disk_cache::Entry* tmp_entry_ptr = entry.get();
 
-  HeadersCallback headers_callback = base::Bind(MatchDidReadHeaderData,
-                                                request,
-                                                callback,
-                                                blob_storage,
-                                                base::Passed(entry.Pass()));
+  net::CompletionCallback read_header_callback =
+      base::Bind(MatchDidReadHeaderData,
+                 request,
+                 callback,
+                 blob_storage,
+                 base::Passed(entry.Pass()),
+                 buffer);
 
-  ReadHeaders(tmp_entry_ptr, headers_callback);
+  int read_rv = tmp_entry_ptr->ReadData(
+      INDEX_HEADERS, 0, buffer.get(), buffer->size(), read_header_callback);
+
+  if (read_rv != net::ERR_IO_PENDING)
+    read_header_callback.Run(read_rv);
 }
 
 void MatchDidReadHeaderData(
@@ -378,24 +376,36 @@ void MatchDidReadHeaderData(
     const ServiceWorkerCache::ResponseCallback& callback,
     base::WeakPtr<storage::BlobStorageContext> blob_storage,
     disk_cache::ScopedEntryPtr entry,
-    scoped_ptr<ServiceWorkerRequestResponseHeaders> headers) {
-  if (!headers) {
+    const scoped_refptr<net::IOBufferWithSize>& buffer,
+    int rv) {
+  if (rv != buffer->size()) {
+    callback.Run(ServiceWorkerCache::ErrorTypeStorage,
+                 scoped_ptr<ServiceWorkerResponse>(),
+                 scoped_ptr<storage::BlobDataHandle>());
+
+    return;
+  }
+
+  ServiceWorkerRequestResponseHeaders headers;
+
+  if (!headers.ParseFromArray(buffer->data(), buffer->size())) {
     callback.Run(ServiceWorkerCache::ErrorTypeStorage,
                  scoped_ptr<ServiceWorkerResponse>(),
                  scoped_ptr<storage::BlobDataHandle>());
+
     return;
   }
 
   scoped_ptr<ServiceWorkerResponse> response(
       new ServiceWorkerResponse(request->url,
-                                headers->status_code(),
-                                headers->status_text(),
+                                headers.status_code(),
+                                headers.status_text(),
                                 std::map<std::string, std::string>(),
                                 ""));
 
-  for (int i = 0; i < headers->response_headers_size(); ++i) {
+  for (int i = 0; i < headers.response_headers_size(); ++i) {
     const ServiceWorkerRequestResponseHeaders::HeaderMap header =
-        headers->response_headers(i);
+        headers.response_headers(i);
     response->headers.insert(std::make_pair(header.name(), header.value()));
   }
 
@@ -413,6 +423,7 @@ void MatchDidReadHeaderData(
     callback.Run(ServiceWorkerCache::ErrorTypeStorage,
                  scoped_ptr<ServiceWorkerResponse>(),
                  scoped_ptr<storage::BlobDataHandle>());
+
     return;
   }
 
@@ -538,43 +549,6 @@ void DeleteDidOpenEntry(ServiceWorkerFetchRequest* request,
   callback.Run(ServiceWorkerCache::ErrorTypeOK);
 }
 
-void ReadHeaders(disk_cache::Entry* entry, const HeadersCallback& callback) {
-  DCHECK(entry);
-
-  scoped_refptr<net::IOBufferWithSize> buffer(
-      new net::IOBufferWithSize(entry->GetDataSize(INDEX_HEADERS)));
-
-  net::CompletionCallback read_header_callback =
-      base::Bind(ReadHeadersDidReadHeaderData, entry, callback, buffer);
-
-  int read_rv = entry->ReadData(
-      INDEX_HEADERS, 0, buffer.get(), buffer->size(), read_header_callback);
-
-  if (read_rv != net::ERR_IO_PENDING)
-    read_header_callback.Run(read_rv);
-}
-
-void ReadHeadersDidReadHeaderData(
-    disk_cache::Entry* entry,
-    const HeadersCallback& callback,
-    const scoped_refptr<net::IOBufferWithSize>& buffer,
-    int rv) {
-  if (rv != buffer->size()) {
-    callback.Run(scoped_ptr<ServiceWorkerRequestResponseHeaders>());
-    return;
-  }
-
-  scoped_ptr<ServiceWorkerRequestResponseHeaders> headers(
-      new ServiceWorkerRequestResponseHeaders());
-
-  if (!headers->ParseFromArray(buffer->data(), buffer->size())) {
-    callback.Run(scoped_ptr<ServiceWorkerRequestResponseHeaders>());
-    return;
-  }
-
-  callback.Run(headers.Pass());
-}
-
 void CreateBackendDidCreate(const ServiceWorkerCache::ErrorCallback& callback,
                             scoped_ptr<ScopedBackendPtr> backend_ptr,
                             base::WeakPtr<ServiceWorkerCache> cache,
@@ -583,49 +557,12 @@ void CreateBackendDidCreate(const ServiceWorkerCache::ErrorCallback& callback,
     callback.Run(ServiceWorkerCache::ErrorTypeStorage);
     return;
   }
-
   cache->set_backend(backend_ptr->Pass());
   callback.Run(ServiceWorkerCache::ErrorTypeOK);
 }
 
 }  // namespace
 
-// The state needed to pass between ServiceWorkerCache::Keys callbacks.
-struct ServiceWorkerCache::KeysContext {
-  KeysContext(const ServiceWorkerCache::RequestsCallback& callback,
-              base::WeakPtr<ServiceWorkerCache> cache)
-      : original_callback(callback),
-        cache(cache),
-        out_keys(new ServiceWorkerCache::Requests()),
-        backend_iterator(NULL),
-        enumerated_entry(NULL) {}
-
-  ~KeysContext() {
-    for (size_t i = 0, max = entries.size(); i < max; ++i)
-      entries[i]->Close();
-    if (enumerated_entry)
-      enumerated_entry->Close();
-    if (cache && backend_iterator)
-      cache->backend_->EndEnumeration(&backend_iterator);
-  }
-
-  // The callback passed to the Keys() function.
-  ServiceWorkerCache::RequestsCallback original_callback;
-
-  // The ServiceWorkerCache that Keys was called on.
-  base::WeakPtr<ServiceWorkerCache> cache;
-
-  // The vector of open entries in the backend.
-  Entries entries;
-
-  // The output of the Keys function.
-  scoped_ptr<ServiceWorkerCache::Requests> out_keys;
-
-  // Used for enumerating cache entries.
-  void* backend_iterator;
-  disk_cache::Entry* enumerated_entry;
-};
-
 // static
 scoped_ptr<ServiceWorkerCache> ServiceWorkerCache::CreateMemoryCache(
     net::URLRequestContext* request_context,
@@ -674,7 +611,7 @@ void ServiceWorkerCache::CreateBackend(const ErrorCallback& callback) {
   // debugging why the QuickStressBody unittest fails with it.
   int rv = disk_cache::CreateCacheBackend(
       cache_type,
-      net::CACHE_BACKEND_SIMPLE,
+      net::CACHE_BACKEND_DEFAULT,
       path_,
       kMaxCacheBytes,
       false, /* force */
@@ -764,35 +701,6 @@ void ServiceWorkerCache::Delete(ServiceWorkerFetchRequest* request,
     open_entry_callback.Run(rv);
 }
 
-void ServiceWorkerCache::Keys(const RequestsCallback& callback) {
-  DCHECK(backend_);
-
-  // 1. Iterate through all of the entries, open them, and add them to a vector.
-  // 2. For each open entry:
-  //  2.1. Read the headers into a protobuf.
-  //  2.2. Copy the protobuf into a ServiceWorkerFetchRequest (a "key").
-  //  2.3. Push the response into a vector of requests to be returned.
-  // 3. Return the vector of requests (keys).
-
-  // The entries have to be loaded into a vector first because enumeration loops
-  // forever if you read data from a cache entry while enumerating.
-
-  scoped_ptr<KeysContext> keys_context(
-      new KeysContext(callback, weak_ptr_factory_.GetWeakPtr()));
-
-  void** backend_iterator = &keys_context->backend_iterator;
-  disk_cache::Entry** enumerated_entry = &keys_context->enumerated_entry;
-
-  net::CompletionCallback open_entry_callback =
-      base::Bind(KeysDidOpenNextEntry, base::Passed(keys_context.Pass()));
-
-  int rv = backend_->OpenNextEntry(
-      backend_iterator, enumerated_entry, open_entry_callback);
-
-  if (rv != net::ERR_IO_PENDING)
-    open_entry_callback.Run(rv);
-}
-
 bool ServiceWorkerCache::HasCreatedBackend() const {
   return backend_;
 }
@@ -807,87 +715,4 @@ ServiceWorkerCache::ServiceWorkerCache(
       weak_ptr_factory_(this) {
 }
 
-// static
-void ServiceWorkerCache::KeysDidOpenNextEntry(
-    scoped_ptr<KeysContext> keys_context,
-    int rv) {
-  if (rv == net::ERR_FAILED) {
-    DCHECK(!keys_context->enumerated_entry);
-    // Enumeration is complete, extract the requests from the entries.
-    Entries::iterator iter = keys_context->entries.begin();
-    KeysProcessNextEntry(keys_context.Pass(), iter);
-    return;
-  }
-
-  base::WeakPtr<ServiceWorkerCache> cache = keys_context->cache;
-  if (rv < 0 || !cache) {
-    keys_context->original_callback.Run(ErrorTypeStorage,
-                                        scoped_ptr<Requests>());
-    return;
-  }
-
-  // Store the entry.
-  keys_context->entries.push_back(keys_context->enumerated_entry);
-  keys_context->enumerated_entry = NULL;
-
-  // Enumerate the next entry.
-  void** backend_iterator = &keys_context->backend_iterator;
-  disk_cache::Entry** enumerated_entry = &keys_context->enumerated_entry;
-
-  net::CompletionCallback open_entry_callback =
-      base::Bind(KeysDidOpenNextEntry, base::Passed(keys_context.Pass()));
-
-  rv = cache->backend_->OpenNextEntry(
-      backend_iterator, enumerated_entry, open_entry_callback);
-
-  if (rv != net::ERR_IO_PENDING)
-    open_entry_callback.Run(rv);
-}
-
-// static
-void ServiceWorkerCache::KeysProcessNextEntry(
-    scoped_ptr<KeysContext> keys_context,
-    const Entries::iterator& iter) {
-  if (iter == keys_context->entries.end()) {
-    // All done. Return all of the keys.
-    keys_context->original_callback.Run(ErrorTypeOK,
-                                        keys_context->out_keys.Pass());
-    return;
-  }
-
-  ReadHeaders(
-      *iter,
-      base::Bind(KeysDidReadHeaders, base::Passed(keys_context.Pass()), iter));
-}
-
-// static
-void ServiceWorkerCache::KeysDidReadHeaders(
-    scoped_ptr<KeysContext> keys_context,
-    const Entries::iterator& iter,
-    scoped_ptr<ServiceWorkerRequestResponseHeaders> headers) {
-  disk_cache::Entry* entry = *iter;
-
-  if (headers) {
-    keys_context->out_keys->push_back(
-        ServiceWorkerFetchRequest(GURL(entry->GetKey()),
-                                  headers->method(),
-                                  std::map<std::string, std::string>(),
-                                  GURL(),
-                                  false));
-
-    std::map<std::string, std::string>& req_headers =
-        keys_context->out_keys->back().headers;
-
-    for (int i = 0; i < headers->request_headers_size(); ++i) {
-      const ServiceWorkerRequestResponseHeaders::HeaderMap header =
-          headers->request_headers(i);
-      req_headers.insert(std::make_pair(header.name(), header.value()));
-    }
-  } else {
-    entry->Doom();
-  }
-
-  KeysProcessNextEntry(keys_context.Pass(), iter + 1);
-}
-
 }  // namespace content