root/ROOT/RRawFileUnix.hxx

0001 // @(#)root/io:$Id$
0002 // Author: Jakob Blomer
0003
0004 /*************************************************************************
0005  * Copyright (C) 1995-2018, Rene Brun and Fons Rademakers.               *
0006  * All rights reserved.                                                  *
0007  *                                                                       *
0008  * For the licensing terms see $ROOTSYS/LICENSE.                         *
0009  * For the list of contributors see $ROOTSYS/README/CREDITS.             *
0010  *************************************************************************/
0011
0012 #ifndef ROOT_RRawFileUnix
0013 #define ROOT_RRawFileUnix
0014
0015 #include <ROOT/RRawFile.hxx>
0016 #include <string_view>
0017
0018 #include <cstddef>
0019 #include <cstdint>
0020
0021 namespace ROOT {
0022 namespace Internal {
0023
0024 /**
0025  * \class RRawFileUnix RRawFileUnix.hxx
0026  * \ingroup IO
0027  *
0028  * The RRawFileUnix class uses POSIX calls to read from a mounted file system. Thus the path name can refer,
0029  * for instance, to a named pipe instead of a regular file.
0030  */
0031 class RRawFileUnix : public RRawFile {
0032 private:
0033    int fFileDes = -1;
0034
0035 protected:
0036    void OpenImpl() final;
0037    size_t ReadAtImpl(void *buffer, size_t nbytes, std::uint64_t offset) final;
0038    void ReadVImpl(RIOVec *ioVec, unsigned int nReq) final;
0039    std::uint64_t GetSizeImpl() final;
0040    void SetDiscourageReadAheadImpl(bool value) final;
0041
0042 public:
0043    RRawFileUnix(std::string_view url, RRawFile::ROptions options);
0044    ~RRawFileUnix() override;
0045    std::unique_ptr<RRawFile> Clone() const final;
0046    int GetFd() const { return fFileDes; }
0047 };
0048
0049 } // namespace Internal
0050 } // namespace ROOT
0051
0052 #endif