CPPUtil/UtilFileDescriptor.hpp

   1 //
   2 //  UtilFileDescriptor.hpp
   3 //  CPPUtil
   4 //
   5 //  Created by James McIlree on 4/16/13.
   6 //  Copyright (c) 2013 Apple. All rights reserved.
   7 //
   8
   9 #ifndef CPPUtil_UtilFileDescriptor_hpp
  10 #define CPPUtil_UtilFileDescriptor_hpp
  11
  12 class FileDescriptor {
  13     protected:
  14         int _fd;
  15
  16         // FD's aren't reference counted, we allow move semantics but
  17         // not copy semantics. Disable the copy constructor and copy
  18         // assignment.
  19         FileDescriptor(const FileDescriptor& that) = delete;
  20         FileDescriptor& operator=(const FileDescriptor& other) = delete;
  21
  22     public:
  23
  24         FileDescriptor() : _fd(-1)                              {}
  25         FileDescriptor(int fd) : _fd(fd)                        {}
  26
  27         template <typename... Args>
  28         FileDescriptor(Args&& ... args) :
  29                 _fd(open(static_cast<Args &&>(args)...))
  30         {
  31         }
  32
  33         FileDescriptor (FileDescriptor&& rhs) noexcept :
  34                 _fd(rhs._fd)
  35         {
  36                 rhs._fd = -1;
  37         }
  38
  39         ~FileDescriptor()                                       { close(); }
  40
  41         FileDescriptor& operator=(int fd)                       { close(); _fd = fd; return *this; }
  42         FileDescriptor& operator=(FileDescriptor&& rhs)         { std::swap(_fd, rhs._fd); return *this; }
  43
  44         bool is_open() const                                    { return _fd > -1 ? true : false; }
  45         void close()                                            { if (is_open()) { ::close(_fd); _fd = -1; } }
  46
  47         explicit operator bool() const                          { return is_open(); }
  48         operator int() const                                    { return _fd; }
  49 };
  50
  51
  52 #endif