net: Implement canceling of all async operations in FileStream.

webkit/glue/webfileutilities_impl.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 "webkit/glue/webfileutilities_impl.h"
 
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "net/base/file_stream.h"
@@ skipping 98 matching lines @@
     return;
   if (base::ClosePlatformFile(handle))
     handle = base::kInvalidPlatformFileValue;
 }
 
 long long WebFileUtilitiesImpl::seekFile(base::PlatformFile handle,
                                          long long offset,
                                          int origin) {
   if (handle == base::kInvalidPlatformFileValue)
     return -1;
-  net::FileStream file_stream(handle, 0, NULL);
-  return file_stream.SeekSync(static_cast<net::Whence>(origin), offset);
+  return base::SeekPlatformFile(handle,
+                                static_cast<base::PlatformFileWhence>(origin),
+                                offset);
 }
 
 bool WebFileUtilitiesImpl::truncateFile(base::PlatformFile handle,
                                         long long offset) {
   if (handle == base::kInvalidPlatformFileValue || offset < 0)
     return false;
-  net::FileStream file_stream(handle, base::PLATFORM_FILE_WRITE, NULL);
-  return file_stream.Truncate(offset) >= 0;
+  return base::TruncatePlatformFile(handle, offset);
 }
 
 int WebFileUtilitiesImpl::readFromFile(base::PlatformFile handle,
                                        char* data,
                                        int length) {
   if (handle == base::kInvalidPlatformFileValue || !data || length <= 0)
     return -1;
-  std::string buffer;
-  buffer.resize(length);
-  net::FileStream file_stream(handle, base::PLATFORM_FILE_READ, NULL);
-  return file_stream.ReadSync(data, length);
+  return base::ReadPlatformFileCurPosNoBestEffort(handle, data, length);
 }
 
 int WebFileUtilitiesImpl::writeToFile(base::PlatformFile handle,
                                       const char* data,
                                       int length) {
   if (handle == base::kInvalidPlatformFileValue || !data || length <= 0)
     return -1;
-  net::FileStream file_stream(handle, base::PLATFORM_FILE_WRITE, NULL);
-  return file_stream.WriteSync(data, length);
+  return base::WritePlatformFileCurPosNoBestEffort(handle, data, length);
 }
 
 }  // namespace webkit_glue