Remove void** from disk_cache interface.

net/disk_cache/blockfile/backend_impl.cc

 // Copyright (c) 2012 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 "net/disk_cache/blockfile/backend_impl.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/files/file.h"
 #include "base/files/file_path.h"
@@ skipping 599 matching lines @@
 
   DCHECK(iter);
 
   const int kListsToSearch = 3;
   scoped_refptr<EntryImpl> entries[kListsToSearch];
   scoped_ptr<Rankings::Iterator> iterator(
       reinterpret_cast<Rankings::Iterator*>(*iter));
   *iter = NULL;
 
   if (!iterator.get()) {
     iterator.reset(new Rankings::Iterator(&rankings_));

[gavinp, 2014/09/19 16:09:35]

Aha, the void** was really a scoped_ptr, very similar to the implementation in
simple cache that was leaking.

     bool ret = false;
 
     // Get an entry from each list.
     for (int i = 0; i < kListsToSearch; i++) {
       EntryImpl* temp = NULL;
       ret |= OpenFollowingEntryFromList(static_cast<Rankings::List>(i),
                                         &iterator->nodes[i], &temp);
       entries[i].swap(&temp);  // The entry was already addref'd.
     }
     if (!ret)
@@ skipping 612 matching lines @@
   return net::ERR_IO_PENDING;
 }
 
 int BackendImpl::DoomEntriesSince(const base::Time initial_time,
                                   const CompletionCallback& callback) {
   DCHECK(!callback.is_null());
   background_queue_.DoomEntriesSince(initial_time, callback);
   return net::ERR_IO_PENDING;
 }
 
-int BackendImpl::OpenNextEntry(void** iter, Entry** next_entry,
-                               const CompletionCallback& callback) {
-  DCHECK(!callback.is_null());
-  background_queue_.OpenNextEntry(iter, next_entry, callback);
-  return net::ERR_IO_PENDING;
-}
+class BackendImpl::IteratorImpl : public Backend::Iterator {
+ public:
+  explicit IteratorImpl(base::WeakPtr<InFlightBackendIO> background_queue)
+      : background_queue_(background_queue), data_(NULL) {
+  }
 
-void BackendImpl::EndEnumeration(void** iter) {
-  background_queue_.EndEnumeration(*iter);

[gavinp, 2014/09/19 16:09:35]

This turns out to be important.

-  *iter = NULL;
+  virtual int OpenNextEntry(Entry** next_entry,
+                            const net::CompletionCallback& callback) OVERRIDE {
+    if (!background_queue_)
+      return net::ERR_FAILED;
+    background_queue_->OpenNextEntry(&data_, next_entry, callback);
+    return net::ERR_IO_PENDING;
+  }
+
+ private:
+  const base::WeakPtr<InFlightBackendIO> background_queue_;
+  void* data_;
+};
+
+scoped_ptr<Backend::Iterator> BackendImpl::CreateIterator() {
+  return scoped_ptr<Backend::Iterator>(new IteratorImpl(GetBackgroundQueue()));
 }
 
 void BackendImpl::GetStats(StatsItems* stats) {
   if (disabled_)
     return;
 
   std::pair<std::string, std::string> item;
 
   item.first = "Entries";
   item.second = base::StringPrintf("%d", data_->header.num_entries);
@@ skipping 793 matching lines @@
     if (total_memory > kMaxBuffersSize || total_memory <= 0)
       total_memory = kMaxBuffersSize;
 
     done = true;
   }
 
   return static_cast<int>(total_memory);
 }
 
 }  // namespace disk_cache