Clean up PnaclTranslationCache interface

chrome/browser/nacl_host/pnacl_translation_cache.h

 // Copyright 2013 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.
 
 #ifndef CHROME_BROWSER_NACL_HOST_PNACL_TRANSLATION_CACHE_H_
 #define CHROME_BROWSER_NACL_HOST_PNACL_TRANSLATION_CACHE_H_
 
 #include <map>
 
 #include "base/callback.h"
 #include "base/files/file_path.h"
 #include "base/memory/weak_ptr.h"
 #include "net/base/cache_type.h"
 
 namespace base {
 class MessageLoopProxy;
 }
 
 namespace disk_cache {
 class Backend;
 }
 
+namespace nacl {
+struct PnaclCacheInfo;
+}
+
+namespace net {
+class DrainableIOBuffer;
+}
+
 namespace pnacl {
 typedef base::Callback<void(int)> CompletionCallback;
+typedef base::Callback<void(int, scoped_refptr<net::DrainableIOBuffer>)>
+    GetNexeCallback;
 class PnaclTranslationCacheEntry;
 extern const int kMaxMemCacheSize;
 
 class PnaclTranslationCache
     : public base::SupportsWeakPtr<PnaclTranslationCache> {
  public:
   PnaclTranslationCache();
   virtual ~PnaclTranslationCache();
 
   // Initialize the translation cache in |cache_dir| (or in memory if
   // |in_memory| is true). Call |callback| with a 0 argument on sucess and
   // <0 otherwise.
   int InitCache(const base::FilePath& cache_dir,
                 bool in_memory,
                 const CompletionCallback& callback);
 
-  // Store the nexe in the translation cache.
-  void StoreNexe(const std::string& key, const std::string& nexe);
+  // Store the nexe in the translation cache. A reference to |nexe_data| is
+  // held until completion or cancellation.
+  void StoreNexe(const std::string& key, net::DrainableIOBuffer* nexe_data);
 
   // Store the nexe in the translation cache, and call |callback| with
   // the result. The result passed to the callback is 0 on success and
-  // <0 otherwise.
+  // <0 otherwise. A reference to |nexe_data| is held until completion
+  // or cancellation.
   void StoreNexe(const std::string& key,
-                 const std::string& nexe,
+                 net::DrainableIOBuffer* nexe_data,
                  const CompletionCallback& callback);
 
   // Retrieve the nexe from the translation cache. Write the data into |nexe|
-  // and call |callback| with the result (0 on success and <0 otherwise)
-  void GetNexe(const std::string& key,
-               std::string* nexe,
-               const CompletionCallback& callback);
+  // and call |callback|, passing a result code (0 on success and <0 otherwise),
+  // and a DrainableIOBuffer with the data.
+  void GetNexe(const std::string& key, const GetNexeCallback& callback);
 
   // Return the number of entries in the cache backend.
   int Size();
 
+  // Return the cache key for |info|
+  static std::string GetKey(const nacl::PnaclCacheInfo& info);
+
  private:
   friend class PnaclTranslationCacheEntry;
+  friend class PnaclTranslationCacheTest;
   // PnaclTranslationCacheEntry should only use the
   // OpComplete and backend methods on PnaclTranslationCache.
   void OpComplete(PnaclTranslationCacheEntry* entry);
   disk_cache::Backend* backend() { return disk_cache_; }
 
   int InitWithDiskBackend(const base::FilePath& disk_cache_dir,
                           int cache_size,
                           const CompletionCallback& callback);
 
   int InitWithMemBackend(int cache_size, const CompletionCallback& callback);
 
   int Init(net::CacheType,
            const base::FilePath& directory,
            int cache_size,
            const CompletionCallback& callback);
 
   void OnCreateBackendComplete(int rv);
 
   disk_cache::Backend* disk_cache_;
   CompletionCallback init_callback_;
   bool in_memory_;
   std::map<void*, scoped_refptr<PnaclTranslationCacheEntry> > open_entries_;
 
   DISALLOW_COPY_AND_ASSIGN(PnaclTranslationCache);
 };
 
 }  // namespace pnacl
 
 #endif  // CHROME_BROWSER_NACL_HOST_PNACL_TRANSLATION_CACHE_H_