1 // Copyright 2013 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 "base/files/memory_mapped_file.h" 6 7 #include <sys/mman.h> 8 #include <sys/stat.h> 9 #include <unistd.h> 10 11 #include "base/logging.h" 12 #include "base/posix/eintr_wrapper.h" 13 #include "base/threading/thread_restrictions.h" 14 15 namespace base { 16 17 MemoryMappedFile::MemoryMappedFile() 18 : file_(kInvalidPlatformFileValue), 19 data_(NULL), 20 length_(0) { 21 } 22 23 bool MemoryMappedFile::MapFileToMemoryInternal() { 24 ThreadRestrictions::AssertIOAllowed(); 25 26 struct stat file_stat; 27 if (fstat(file_, &file_stat) == kInvalidPlatformFileValue) { 28 DLOG(ERROR) << "Couldn't fstat " << file_ << ", errno " << errno; 29 return false; 30 } 31 length_ = file_stat.st_size; 32 33 data_ = static_cast<uint8*>( 34 mmap(NULL, length_, PROT_READ, MAP_SHARED, file_, 0)); 35 if (data_ == MAP_FAILED) 36 DLOG(ERROR) << "Couldn't mmap " << file_ << ", errno " << errno; 37 38 return data_ != MAP_FAILED; 39 } 40 41 void MemoryMappedFile::CloseHandles() { 42 ThreadRestrictions::AssertIOAllowed(); 43 44 if (data_ != NULL) 45 munmap(data_, length_); 46 if (file_ != kInvalidPlatformFileValue) 47 ignore_result(HANDLE_EINTR(close(file_))); 48 49 data_ = NULL; 50 length_ = 0; 51 file_ = kInvalidPlatformFileValue; 52 } 53 54 } // namespace base 55