Remove void** from disk_cache interface.

net/disk_cache/blockfile/backend_impl.cc

Index: net/disk_cache/blockfile/backend_impl.cc
diff --git a/net/disk_cache/blockfile/backend_impl.cc b/net/disk_cache/blockfile/backend_impl.cc
index c38b2bb9e33b49fa7e4945edc7380b235b5d3b8a..e3683286ed04efc638ebb74462222d2c0982014d 100644
--- a/net/disk_cache/blockfile/backend_impl.cc
+++ b/net/disk_cache/blockfile/backend_impl.cc
@@ -1250,16 +1250,27 @@ int BackendImpl::DoomEntriesSince(const base::Time initial_time,
   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) {