1 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "net/disk_cache/mapped_file.h" 6 7 #include <errno.h> 8 #include <sys/mman.h> 9 10 #include "base/file_path.h" 11 #include "base/logging.h" 12 #include "net/disk_cache/disk_cache.h" 13 14 namespace disk_cache { 15 16 void* MappedFile::Init(const FilePath& name, size_t size) { 17 DCHECK(!init_); 18 if (init_ || !File::Init(name)) 19 return NULL; 20 21 if (!size) 22 size = GetLength(); 23 24 buffer_ = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, 25 platform_file(), 0); 26 init_ = true; 27 DCHECK(reinterpret_cast<intptr_t>(buffer_) != -1); 28 if (reinterpret_cast<intptr_t>(buffer_) == -1) 29 buffer_ = 0; 30 31 view_size_ = size; 32 return buffer_; 33 } 34 35 bool MappedFile::Load(const FileBlock* block) { 36 size_t offset = block->offset() + view_size_; 37 return Read(block->buffer(), block->size(), offset); 38 } 39 40 bool MappedFile::Store(const FileBlock* block) { 41 size_t offset = block->offset() + view_size_; 42 return Write(block->buffer(), block->size(), offset); 43 } 44 45 MappedFile::~MappedFile() { 46 if (!init_) 47 return; 48 49 if (buffer_) { 50 int ret = munmap(buffer_, view_size_); 51 DCHECK(0 == ret); 52 } 53 } 54 55 } // namespace disk_cache 56