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 34 matching lines @@
 
 // Seems like ~240 MB correspond to less than 50k entries for 99% of the people.
 // Note that the actual target is to keep the index table load factor under 55%
 // for most users.
 const int k64kEntriesStore = 240 * 1000 * 1000;
 const int kBaseTableLen = 64 * 1024;
 
 // Avoid trimming the cache for the first 5 minutes (10 timer ticks).
 const int kTrimDelay = 10;
 
+class BackendEnumerationState : public disk_cache::Backend::EnumerationState {
+ public:
+  explicit BackendEnumerationState(
+      base::WeakPtr<disk_cache::InFlightBackendIO> background_queue)
+      : background_queue_(background_queue),
+        data_(NULL) {}
+
+  virtual ~BackendEnumerationState() {
+    if (background_queue_)
+      background_queue_->EndEnumeration(*data());
+  }
+
+  void** data() { return &data_; }
+
+ private:
+  base::WeakPtr<disk_cache::InFlightBackendIO> background_queue_;
+  void* data_;
+};
+
 int DesiredIndexTableLen(int32 storage_size) {
   if (storage_size <= k64kEntriesStore)
     return kBaseTableLen;
   if (storage_size <= k64kEntriesStore * 2)
     return kBaseTableLen * 2;
   if (storage_size <= k64kEntriesStore * 4)
     return kBaseTableLen * 4;
   if (storage_size <= k64kEntriesStore * 8)
     return kBaseTableLen * 8;
 
@@ skipping 256 matching lines @@
   }
   block_files_.CloseFiles();
   FlushIndex();
   index_ = NULL;
   ptr_factory_.InvalidateWeakPtrs();
   done_.Signal();
 }
 
 // ------------------------------------------------------------------------
 
-int BackendImpl::OpenPrevEntry(void** iter, Entry** prev_entry,
+int BackendImpl::OpenPrevEntry(Iterator* iter, Entry** prev_entry,
                                const CompletionCallback& callback) {
   DCHECK(!callback.is_null());
-  background_queue_.OpenPrevEntry(iter, prev_entry, callback);
+  if (!*iter)
+    iter->reset(new BackendEnumerationState(GetBackgroundQueue()));
+  BackendEnumerationState* state =
+      static_cast<BackendEnumerationState*>(iter->get());
+
+  background_queue_.OpenPrevEntry(state->data(), prev_entry, callback);
   return net::ERR_IO_PENDING;
 }
 
 int BackendImpl::SyncOpenEntry(const std::string& key, Entry** entry) {
   DCHECK(entry);
   *entry = OpenEntryImpl(key);
   return (*entry) ? net::OK : net::ERR_FAILED;
 }
 
 int BackendImpl::SyncCreateEntry(const std::string& key, Entry** entry) {
@@ skipping 847 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,
+int BackendImpl::OpenNextEntry(Iterator* iter, Entry** next_entry,
                                const CompletionCallback& callback) {
+  // TODO(gavinp): Remove all void** iter from cache.
   DCHECK(!callback.is_null());
-  background_queue_.OpenNextEntry(iter, next_entry, callback);
+  if (!*iter)
+    iter->reset(new BackendEnumerationState(GetBackgroundQueue()));
+  BackendEnumerationState* state =
+      static_cast<BackendEnumerationState*>(iter->get());
+
+  background_queue_.OpenNextEntry(state->data(), next_entry, callback);
   return net::ERR_IO_PENDING;
 }
 
-void BackendImpl::EndEnumeration(void** iter) {
-  background_queue_.EndEnumeration(*iter);
-  *iter = NULL;
-}
-
 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);
   stats->push_back(item);
 
@@ skipping 871 matching lines @@
     if (total_memory > kMaxBuffersSize || total_memory <= 0)
       total_memory = kMaxBuffersSize;
 
     done = true;
   }
 
   return static_cast<int>(total_memory);
 }
 
 }  // namespace disk_cache