Move Preload() code to MappedFile

net/disk_cache/blockfile/block_files.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/block_files.h"
 
 #include "base/atomicops.h"
 #include "base/files/file_path.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_util.h"
@@ skipping 490 matching lines @@
     }
   }
 
   if (static_cast<int>(file_len) <
       header->max_entries * header->entry_size + kBlockHeaderSize) {
     LOG(ERROR) << "File too small " << name.value();
     return false;
   }
 
   if (index == 0) {
-    // Load the links file into memory with a single read.
-    scoped_ptr<char[]> buf(new char[file_len]);
-    if (!file->Read(buf.get(), file_len, 0))
+    // Load the links file into memory.
+    if (!file->Preload())
       return false;
   }
 
   ScopedFlush flush(file.get());
   DCHECK(!block_files_[index]);
   file.swap(&block_files_[index]);
   return true;
 }
 
 bool BlockFiles::GrowBlockFile(MappedFile* file, BlockFileHeader* header) {
@@ skipping 200 matching lines @@
 }
 
 base::FilePath BlockFiles::Name(int index) {
   // The file format allows for 256 files.
   DCHECK(index < 256 && index >= 0);
   std::string tmp = base::StringPrintf("%s%d", kBlockName, index);
   return path_.AppendASCII(tmp);
 }
 
 }  // namespace disk_cache