Create blobs from Disk Cache entries.

storage/common/data_element.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 STORAGE_COMMON_DATA_ELEMENT_H_
 #define STORAGE_COMMON_DATA_ELEMENT_H_
 
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/time/time.h"
+#include "net/disk_cache/disk_cache.h"
 #include "storage/common/storage_common_export.h"
 #include "url/gurl.h"
 
 namespace storage {
 
 // Represents a base Web data element. This could be either one of
 // bytes, file or blob data.
 class STORAGE_COMMON_EXPORT DataElement {
  public:
   enum Type {
     TYPE_UNKNOWN = -1,
     TYPE_BYTES,
     TYPE_FILE,
     TYPE_BLOB,
     TYPE_FILE_FILESYSTEM,
+    TYPE_DISK_CACHE_ENTRY,
   };
 
   DataElement();
   ~DataElement();
 
   Type type() const { return type_; }
   const char* bytes() const { return bytes_ ? bytes_ : &buf_[0]; }
   const base::FilePath& path() const { return path_; }
   const GURL& filesystem_url() const { return filesystem_url_; }
   const std::string& blob_uuid() const { return blob_uuid_; }
@@ skipping 55 matching lines @@
 
   // Sets TYPE_BLOB data with range.
   void SetToBlobRange(const std::string& blob_uuid,
                       uint64 offset, uint64 length);
 
   // Sets TYPE_FILE_FILESYSTEM with range.
   void SetToFileSystemUrlRange(const GURL& filesystem_url,
                                uint64 offset, uint64 length,
                                const base::Time& expected_modification_time);
 
+  // Sets TYPE_DISK_CACHE_ENTRY data.
+  void SetToDiskCacheEntry();
+
  private:
   Type type_;
   std::vector<char> buf_;  // For TYPE_BYTES.
   const char* bytes_;  // For TYPE_BYTES.
   base::FilePath path_;  // For TYPE_FILE.
   GURL filesystem_url_;  // For TYPE_FILE_FILESYSTEM.
-  std::string blob_uuid_;
+  std::string blob_uuid_;  // For TYPE_BLOB and TYPE_DISK_CACHE_ENTRY.

[michaeln, 2015/06/12 22:35:10]

where/how is this used for TYPE_DISK_CACHE_ENTRY?

   uint64 offset_;
   uint64 length_;
   base::Time expected_modification_time_;
 };
 
 #if defined(UNIT_TEST)
 inline bool operator==(const DataElement& a, const DataElement& b) {
   if (a.type() != b.type() ||
       a.offset() != b.offset() ||
       a.length() != b.length())
     return false;
   switch (a.type()) {
     case DataElement::TYPE_BYTES:
       return memcmp(a.bytes(), b.bytes(), b.length()) == 0;
     case DataElement::TYPE_FILE:
       return a.path() == b.path() &&
              a.expected_modification_time() == b.expected_modification_time();
     case DataElement::TYPE_BLOB:
       return a.blob_uuid() == b.blob_uuid();
     case DataElement::TYPE_FILE_FILESYSTEM:
       return a.filesystem_url() == b.filesystem_url();
+    case DataElement::TYPE_DISK_CACHE_ENTRY:
+      return true;  // XYZZY really?
     case DataElement::TYPE_UNKNOWN:
       NOTREACHED();
       return false;
   }
   return false;
 }
 
 inline bool operator!=(const DataElement& a, const DataElement& b) {
   return !(a == b);
 }
 #endif  // defined(UNIT_TEST)
 
 }  // namespace storage
 
 #endif  // STORAGE_COMMON_DATA_ELEMENT_H_