| // Copyright 2013 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/memory_mapped_file.h" |
| |
| #include "base/files/file_path.h" |
| #include "base/logging.h" |
| #include "base/metrics/histogram.h" |
| #include "base/strings/string16.h" |
| #include "base/threading/thread_restrictions.h" |
| |
| namespace base { |
| |
| MemoryMappedFile::MemoryMappedFile() |
| : file_(INVALID_HANDLE_VALUE), |
| file_mapping_(INVALID_HANDLE_VALUE), |
| data_(NULL), |
| length_(INVALID_FILE_SIZE) { |
| } |
| |
| bool MemoryMappedFile::InitializeAsImageSection(const FilePath& file_name) { |
| if (IsValid()) |
| return false; |
| file_ = CreatePlatformFile(file_name, PLATFORM_FILE_OPEN | PLATFORM_FILE_READ, |
| NULL, NULL); |
| |
| if (file_ == kInvalidPlatformFileValue) { |
| DLOG(ERROR) << "Couldn't open " << file_name.AsUTF8Unsafe(); |
| return false; |
| } |
| |
| if (!MapFileToMemoryInternalEx(SEC_IMAGE)) { |
| CloseHandles(); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool MemoryMappedFile::MapFileToMemoryInternal() { |
| return MapFileToMemoryInternalEx(0); |
| } |
| |
| bool MemoryMappedFile::MapFileToMemoryInternalEx(int flags) { |
| ThreadRestrictions::AssertIOAllowed(); |
| |
| if (file_ == INVALID_HANDLE_VALUE) |
| return false; |
| |
| length_ = ::GetFileSize(file_, NULL); |
| if (length_ == INVALID_FILE_SIZE) |
| return false; |
| |
| file_mapping_ = ::CreateFileMapping(file_, NULL, PAGE_READONLY | flags, |
| 0, 0, NULL); |
| if (!file_mapping_) { |
| // According to msdn, system error codes are only reserved up to 15999. |
| // http://msdn.microsoft.com/en-us/library/ms681381(v=VS.85).aspx. |
| UMA_HISTOGRAM_ENUMERATION("MemoryMappedFile.CreateFileMapping", |
| logging::GetLastSystemErrorCode(), 16000); |
| return false; |
| } |
| |
| data_ = static_cast<uint8*>( |
| ::MapViewOfFile(file_mapping_, FILE_MAP_READ, 0, 0, 0)); |
| if (!data_) { |
| UMA_HISTOGRAM_ENUMERATION("MemoryMappedFile.MapViewOfFile", |
| logging::GetLastSystemErrorCode(), 16000); |
| } |
| return data_ != NULL; |
| } |
| |
| void MemoryMappedFile::CloseHandles() { |
| if (data_) |
| ::UnmapViewOfFile(data_); |
| if (file_mapping_ != INVALID_HANDLE_VALUE) |
| ::CloseHandle(file_mapping_); |
| if (file_ != INVALID_HANDLE_VALUE) |
| ::CloseHandle(file_); |
| |
| data_ = NULL; |
| file_mapping_ = file_ = INVALID_HANDLE_VALUE; |
| length_ = INVALID_FILE_SIZE; |
| } |
| |
| } // namespace base |