Make SimpleEntryImpl ref counted.

net/disk_cache/simple/simple_entry_impl.h

Index: net/disk_cache/simple/simple_entry_impl.h
diff --git a/net/disk_cache/simple/simple_entry_impl.h b/net/disk_cache/simple/simple_entry_impl.h
index 616aaddf7663fadbd28c782a386cd13d436868c6..7329936ba873bd950ec766501996b0de26f5b947 100644
--- a/net/disk_cache/simple/simple_entry_impl.h
+++ b/net/disk_cache/simple/simple_entry_impl.h
@@ -8,6 +8,7 @@
 #include <string>
 
 #include "base/files/file_path.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/thread_checker.h"
 #include "net/disk_cache/disk_cache.h"
@@ -26,7 +27,8 @@ class SimpleSynchronousEntry;
 // SimpleEntryImpl is the IO thread interface to an entry in the very simple
 // disk cache. It proxies for the SimpleSynchronousEntry, which performs IO
 // on the worker thread.
-class SimpleEntryImpl : public Entry {
+class SimpleEntryImpl : public Entry, public base::RefCounted<SimpleEntryImpl> {
+  friend class base::RefCounted<SimpleEntryImpl>;
  public:
   static int OpenEntry(base::WeakPtr<SimpleIndex> index,
                        const base::FilePath& path,
@@ -80,8 +82,10 @@ class SimpleEntryImpl : public Entry {
   virtual int ReadyForSparseIO(const CompletionCallback& callback) OVERRIDE;
 
  private:
-  SimpleEntryImpl(SimpleSynchronousEntry* synchronous_entry,
-                  base::WeakPtr<SimpleIndex> index);
+  SimpleEntryImpl(base::WeakPtr<SimpleIndex> index,
+                  const base::FilePath& path,
+                  const std::string& key);
+
 
   virtual ~SimpleEntryImpl();
 
@@ -89,37 +93,40 @@ class SimpleEntryImpl : public Entry {
   // OpenEntry(). Constructs the new SimpleEntryImpl (if |result| is net::OK)
   // and passes it back to the caller via |out_entry|. Also runs
   // |completion_callback|.
-  static void CreationOperationComplete(
-      base::WeakPtr<SimpleIndex> index,
+  void CreationOperationComplete(
       const CompletionCallback& completion_callback,
-      const std::string& key,
-      Entry** out_entry,
       SimpleSynchronousEntry* sync_entry);
 
   // Called after a SimpleSynchronousEntry has completed an asynchronous IO
   // operation, such as ReadData() or WriteData(). Calls |completion_callback|.
-  // If |entry| no longer exists, then it ensures |sync_entry| is closed.
-  static void EntryOperationComplete(
-      base::WeakPtr<SimpleIndex> index,
+  void EntryOperationComplete(
       const CompletionCallback& completion_callback,
-      base::WeakPtr<SimpleEntryImpl> entry,
-      SimpleSynchronousEntry* sync_entry,
       int result);
 
+  // Called after a SimpleSynchronousEntry has been successfully created for
+  // this entry. After this call, the SimpleEntryImpl claims |sync_entry| and
+  // is responsible for closing it.
+  void Initialize(SimpleSynchronousEntry* sync_entry);
+
   // Called on construction and also after the completion of asynchronous IO to
   // initialize the IO thread copies of data returned by synchronous accessor
   // functions. Copies data from |synchronous_entry_| into |this|, so that
   // values can be returned during our next IO operation.
   void SetSynchronousData();
 
+  // The disk_cache::Entry API requires a self delete on Close(). At the same
+  // time, we use ref counting to keep the SimpleEntryImpl alive while IO
+  // operations are pending. This |self_| reference is set to |this| at
+  // initialization and holds the implicit reference built in to the API. On
+  // Close(), we call |self_.reset()| so the Entry will self release after

[felipeg, 2013/04/12 15:52:19]

in the actual code you do
self_ = NULL;
change one or the other

[gavinp, 2013/04/13 08:54:35]

Done.

+  // the last pending IO operation completes.
+  scoped_refptr<SimpleEntryImpl> self_;
+
   // All nonstatic SimpleEntryImpl methods should always be called on the IO
   // thread, in all cases. |io_thread_checker_| documents and enforces this.
   base::ThreadChecker io_thread_checker_;
 
-  base::WeakPtrFactory<SimpleEntryImpl> weak_ptr_factory_;
-
-  // |path_| and |key_| are copied from the synchronous entry on construction,
-  // and never updated as they are const.
+  const base::WeakPtr<SimpleIndex> index_;
   const base::FilePath path_;
   const std::string key_;
 
@@ -140,8 +147,6 @@ class SimpleEntryImpl : public Entry {
   // and false after. Used to ensure thread safety by not allowing multiple
   // threads to access the |synchronous_entry_| simultaneously.
   bool synchronous_entry_in_use_by_worker_;
-
-  base::WeakPtr<SimpleIndex> index_;
 };
 
 }  // namespace disk_cache