Convert base::MemoryMappedFile to use File instead of PlatformFile.

base/files/file_win.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 "base/files/file.h"
 
 #include <io.h>
 
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/threading/thread_restrictions.h"
 
 namespace base {
 
-void File::CreateBaseFileUnsafe(const FilePath& name, uint32 flags) {
+void File::InitializeUnsafe(const FilePath& name, uint32 flags) {
   base::ThreadRestrictions::AssertIOAllowed();
   DCHECK(!IsValid());
 
   DWORD disposition = 0;
 
   if (flags & FLAG_OPEN)
     disposition = OPEN_EXISTING;
 
   if (flags & FLAG_CREATE) {
     DCHECK(!disposition);
@@ skipping 163 matching lines @@
 
 int File::WriteAtCurrentPos(const char* data, int size) {
   NOTREACHED();
   return -1;
 }
 
 int File::WriteAtCurrentPosNoBestEffort(const char* data, int size) {
   return WriteAtCurrentPos(data, size);
 }
 
-bool File::Truncate(int64 length) {
+int64 File::GetLength() {
+  base::ThreadRestrictions::AssertIOAllowed();
+  DCHECK(IsValid());
+  LARGE_INTEGER size;
+  if (!::GetFileSizeEx(file_.Get(), &size))
+    return -1;
+
+  return static_cast<int64>(size.QuadPart);
+}
+
+bool File::SetLength(int64 length) {
   base::ThreadRestrictions::AssertIOAllowed();
   DCHECK(IsValid());
 
   // Get the current file pointer.
   LARGE_INTEGER file_pointer;
   LARGE_INTEGER zero;
   zero.QuadPart = 0;
   if (::SetFilePointerEx(file_, zero, &file_pointer, FILE_CURRENT) == 0)
     return false;
 
   LARGE_INTEGER length_li;
   length_li.QuadPart = length;
   // If length > file size, SetFilePointerEx() should extend the file
   // with zeroes on all Windows standard file systems (NTFS, FATxx).
   if (!::SetFilePointerEx(file_, length_li, NULL, FILE_BEGIN))
     return false;
 
   // Set the new file length and move the file pointer to its old position.
   // This is consistent with ftruncate()'s behavior, even when the file
   // pointer points to a location beyond the end of the file.
+  // TODO(rvargas): Emulating ftruncate details seem suspicious and it is not
+  // promised by the interface (nor was promised by PlatformFile). See if this
+  // implementation detail can be removed.
   return ((::SetEndOfFile(file_) != 0) &&
           (::SetFilePointerEx(file_, file_pointer, NULL, FILE_BEGIN) != 0));
 }
 
 bool File::Flush() {
   base::ThreadRestrictions::AssertIOAllowed();
   DCHECK(IsValid());
   return ::FlushFileBuffers(file_) != FALSE;
 }
 
@@ skipping 79 matching lines @@
                                   last_error);
       return FILE_ERROR_FAILED;
   }
 }
 
 void File::SetPlatformFile(PlatformFile file) {
   file_.Set(file);
 }
 
 }  // namespace base