Refactor BaseFile methods to return a DownloadInterruptReason instead of a net::Error.

content/browser/download/base_file_posix.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 "content/browser/download/base_file.h"
+
+#include "base/file_util.h"
+#include "content/public/browser/download_interrupt_reasons.h"
+
+content::DownloadInterruptReason BaseFile::MoveFileAndAdjustPermissions(
+    const FilePath& new_path) {
+  // Similarly, on Unix, we're moving a temp file created with permissions 600
+  // to |new_path|. Here, we try to fix up the destination file with appropriate
+  // permissions.
+  struct stat st;
+  // First check the file existence and create an empty file if it doesn't
+  // exist.
+  if (!file_util::PathExists(new_path)) {
+    int write_error = file_util::WriteFile(new_path, "", 0);
+    if (write_error < 0)
+      return LogSystemError("WriteFile", errno);
+  }
+  int stat_error = stat(new_path.value().c_str(), &st);
+  bool stat_succeeded = (stat_error == 0);
+  if (!stat_succeeded)
+    LogSystemError("stat", errno);
+
+  // TODO(estade): Move() falls back to copying and deleting when a simple
+  // rename fails. Copying sucks for large downloads. crbug.com/8737
+  if (!file_util::Move(full_path_, new_path))
+    return LogSystemError("Move", errno);
+
+  if (stat_succeeded) {
+    // On Windows file systems (FAT, NTFS), chmod fails.  This is OK.
+    int chmod_error = chmod(new_path.value().c_str(), st.st_mode);
+    if (chmod_error < 0)
+      LogSystemError("chmod", errno);
+  }
+  return content::DOWNLOAD_INTERRUPT_REASON_NONE;
+}