| // 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 "courgette/memory_allocator.h" |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include <map> |
| |
| #include "base/files/file_util.h" |
| #include "build/build_config.h" |
| |
| #if BUILDFLAG(IS_WIN) |
| |
| #include <windows.h> |
| |
| namespace { |
| |
| // The file is created in the %TEMP% folder. |
| // NOTE: Since the file will be used as backing for a memory allocation, |
| // it will never be so big that size_t cannot represent its size. |
| base::File CreateTempFile() { |
| base::FilePath path; |
| if (!base::CreateTemporaryFile(&path)) |
| return base::File(); |
| |
| int flags = base::File::FLAG_OPEN_ALWAYS | base::File::FLAG_READ | |
| base::File::FLAG_WRITE | base::File::FLAG_DELETE_ON_CLOSE | |
| base::File::FLAG_WIN_TEMPORARY; |
| return base::File(path, flags); |
| } |
| |
| } // namespace |
| |
| namespace courgette { |
| |
| // FileMapping |
| |
| FileMapping::FileMapping() : mapping_(nullptr), view_(nullptr) {} |
| |
| FileMapping::~FileMapping() { |
| Close(); |
| } |
| |
| bool FileMapping::InitializeView(size_t size) { |
| DCHECK(view_ == nullptr); |
| DCHECK(mapping_ != nullptr); |
| view_ = ::MapViewOfFile(mapping_, FILE_MAP_WRITE, 0, 0, size); |
| if (!view_) { |
| Close(); |
| return false; |
| } |
| return true; |
| } |
| |
| bool FileMapping::Create(HANDLE file, size_t size) { |
| DCHECK(file != INVALID_HANDLE_VALUE); |
| DCHECK(!valid()); |
| mapping_ = ::CreateFileMapping(file, nullptr, PAGE_READWRITE, 0, 0, nullptr); |
| if (!mapping_) |
| return false; |
| |
| return InitializeView(size); |
| } |
| |
| void FileMapping::Close() { |
| if (view_) |
| ::UnmapViewOfFile(view_); |
| if (mapping_) |
| ::CloseHandle(mapping_); |
| mapping_ = nullptr; |
| view_ = nullptr; |
| } |
| |
| bool FileMapping::valid() const { |
| return view_ != nullptr; |
| } |
| |
| void* FileMapping::view() const { |
| return view_; |
| } |
| |
| // TempMapping |
| |
| TempMapping::TempMapping() { |
| } |
| |
| TempMapping::~TempMapping() { |
| } |
| |
| bool TempMapping::Initialize(size_t size) { |
| file_ = CreateTempFile(); |
| if (!file_.IsValid()) |
| return false; |
| |
| // TODO(tommi): The assumption here is that the alignment of pointers (this) |
| // is as strict or stricter than the alignment of the element type. This is |
| // not always true, e.g. __m128 has 16-byte alignment. |
| size += sizeof(this); |
| if (!file_.SetLength(size) || |
| !mapping_.Create(file_.GetPlatformFile(), size)) { |
| file_.Close(); |
| return false; |
| } |
| |
| TempMapping** write = reinterpret_cast<TempMapping**>(mapping_.view()); |
| write[0] = this; |
| |
| return true; |
| } |
| |
| void* TempMapping::memory() const { |
| uint8_t* mem = reinterpret_cast<uint8_t*>(mapping_.view()); |
| // The 'this' pointer is written at the start of mapping_.view(), so |
| // go past it. (See Initialize()). |
| if (mem) |
| mem += sizeof(this); |
| DCHECK(mem); |
| return mem; |
| } |
| |
| bool TempMapping::valid() const { |
| return mapping_.valid(); |
| } |
| |
| // static |
| TempMapping* TempMapping::GetMappingFromPtr(void* mem) { |
| TempMapping* ret = nullptr; |
| if (mem) { |
| ret = reinterpret_cast<TempMapping**>(mem)[-1]; |
| } |
| DCHECK(ret); |
| return ret; |
| } |
| |
| } // namespace courgette |
| |
| #endif // BUILDFLAG(IS_WIN) |