1c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Copyright (c) 2008 The Chromium Authors. All rights reserved. 2c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Use of this source code is governed by a BSD-style license that can be 3c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// found in the LICENSE file. 4c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 5c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/test/test_file_util.h" 6c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 7c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include <sys/mman.h> 8c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include <errno.h> 9c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/logging.h" 10c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include "base/file_util.h" 11c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 12c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottnamespace file_util { 13c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 14c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottbool EvictFileFromSystemCache(const FilePath& file) { 15c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // There aren't any really direct ways to purge a file from the UBC. From 16c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // talking with Amit Singh, the safest is to mmap the file with MAP_FILE (the 17c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // default) + MAP_SHARED, then do an msync to invalidate the memory. The next 18c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott // open should then have to load the file from disk. 19c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 20c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott file_util::MemoryMappedFile mapped_file; 21c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (!mapped_file.Initialize(file)) { 22c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DLOG(WARNING) << "failed to memory map " << file.value(); 23c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 24c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 25c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 26c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott if (msync(const_cast<uint8*>(mapped_file.data()), mapped_file.length(), 27c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott MS_INVALIDATE) != 0) { 28c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott DLOG(WARNING) << "failed to invalidate memory map of " << file.value() 29c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott << ", errno: " << errno; 30c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return false; 31c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott } 32c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 33c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott return true; 34c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} 35c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 36c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott} // namespace file_util 37