cosmos::FileBase Class Reference

Base class for File types with ownership of a FileDescriptor. More...

#include <FileBase.hxx>

Inheritance diagram for cosmos::FileBase:

Public Member Functions
	FileBase (const FileBase &)=delete
FileBase &	operator= (const FileBase &)=delete
virtual void	close ()
	Close the current file object.
bool	isOpen () const
	Returns whether currently a FileDescriptor is opened.
FileDescriptor	fd () const
	Allows access to the underlying fd with const semantics.
void	truncate (const off_t length)
Public Member Functions inherited from cosmos::StreamIO
	StreamIO (FileDescriptor &fd)
	StreamIO (const StreamIO &)=delete
StreamIO &	operator= (const StreamIO &)=delete
StreamIO &	operator= (StreamIO &&) noexcept
size_t	read (void *buf, size_t length)
	Read up to length bytes from the file into buf.
size_t	write (const void *buf, size_t length)
	Write up to length bytes from buf into the underlying file.
size_t	write (const std::string_view data)
	string_view wrapper around write(const void*, size_t).
void	readAll (void *buf, size_t length)
	Read all length bytes from the underlying file.
void	readAll (std::string &s, size_t length)
	Like readAll(void*, size_t) using an STL string.
void	writeAll (const void *buf, size_t length)
	Write all length bytes into the underlying file.
void	writeAll (const std::string_view data)
	string_view wrapper around writeAll(const void*, size_t).
bool	read (ReadIOVector &iovec)
	Read data from file into a vector of data regions.
bool	write (WriteIOVector &iovec)
	Write data to file from a vector of data regions.
void	readAll (ReadIOVector &iovec)
	Read into all data regions specified in iovec.
void	writeAll (WriteIOVector &iovec)
	Write all data regions specified in iovec.
off_t	seek (const SeekType type, off_t off)
	Seek to the given offset based on the given offset type.
off_t	seekFromStart (off_t off)
	Seek to the given offset relative to the start of the file.
off_t	seekFromCurrent (off_t off)
	Seek to the given offset relative to the current file position.
off_t	seekFromEnd (off_t off)
	Seek to the given offset relative to the end of the file.

Protected Member Functions
	FileBase (const FileDescriptor fd=FileDescriptor{})
	FileBase (FileBase &&other) noexcept
FileBase &	operator= (FileBase &&other) noexcept

Protected Attributes
FileDescriptor	m_fd
Protected Attributes inherited from cosmos::StreamIO
FileDescriptor &	m_stream_fd

Additional Inherited Members
Public Types inherited from cosmos::StreamIO
enum class	SeekType : int {   SET = SEEK_SET , CUR = SEEK_CUR , END = SEEK_END , DATA = SEEK_DATA ,   HOLE = SEEK_HOLE }
	Different methods for changing the file read/write position. More...

Detailed Description

Base class for File types with ownership of a FileDescriptor.

Implementations of FileBase carry ownership of a FileDescriptor. How this FileDescriptor is obtained is defined by specializations of this class.

This type implements the file close() logic and the moveable-only-semantics i.e. the type is non-copiable, but the ownership of the file descriptor can be transferred to other instances using std::move() and implicit move operations.

This type inherits the StreamIO interface for operating on the file content using streaming file I/O.

Definition at line 22 of file FileBase.hxx.

Constructor & Destructor Documentation

FileBase() [1/2]

cosmos::FileBase::FileBase ( const FileDescriptor fd = FileDescriptor{} )

inlineprotected

Definition at line 26 of file FileBase.hxx.

                                                         {}) :
                StreamIO{m_fd},
                m_fd{fd}
        {}

FileBase() [2/2]

cosmos::FileBase::FileBase ( FileBase && other )

inlineprotectednoexcept

Definition at line 35 of file FileBase.hxx.

                                            :
                        StreamIO{m_fd} {
                *this = std::move(other);
        }

~FileBase()

cosmos::FileBase::~FileBase ( )

virtual

Definition at line 10 of file FileBase.cxx.

                    {
        const auto orig_fd = m_fd.raw();
        try {
                this->close();
        } catch (const std::exception &e) {
                noncritical_error(sprintf("%s: failed to close fd(%d)", __FUNCTION__, to_integral(orig_fd)), e);
        }
}

Member Function Documentation

close()

virtual void cosmos::FileBase::close ( )

inlinevirtual

Close the current file object.

If currently no file is open then this does nothing. If currently an external FileDescriptor is wrapped and auto-close is not set then only the object's state will be invalidated. Otherwise the referenced file descriptor will also be closed on OS-level.

Reimplemented in cosmos::EventFile, cosmos::FDFile, cosmos::TempFile, and cosmos::TimerFD< CLOCK >.

Definition at line 63 of file FileBase.hxx.

                             {
                if (!isOpen())
                        return;
 
                m_fd.close();
        }

fd()

FileDescriptor cosmos::FileBase::fd ( ) const

inline

Allows access to the underlying fd with const semantics.

Definition at line 74 of file FileBase.hxx.

{ return m_fd; }

isOpen()

bool cosmos::FileBase::isOpen ( ) const

inline

Returns whether currently a FileDescriptor is opened.

Definition at line 71 of file FileBase.hxx.

{ return m_fd.valid(); }

operator=()

FileBase & cosmos::FileBase::operator= ( FileBase && other )

inlineprotectednoexcept

Definition at line 40 of file FileBase.hxx.

                                                       {
                m_fd = other.m_fd;
                other.m_fd.reset();
 
                return *this;
        }

truncate()

void cosmos::FileBase::truncate

(

const off_t

length

)

See also

cosmos::fs::truncate().

Definition at line 19 of file FileBase.cxx.

                                         {
        fs::truncate(fd(), bytes);
}

Member Data Documentation

m_fd

FileDescriptor cosmos::FileBase::m_fd

protected

Definition at line 81 of file FileBase.hxx.

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The documentation for this class was generated from the following files:

• include/fs/FileBase.hxx
• src/fs/FileBase.cxx