File descriptor / Socket wrapper. More...

#include <Descriptor.hpp>

Public Member Functions
	Descriptor (const File *file, int flags, mode_t perm)
	~Descriptor ()
	operator int () const throw ()
void	close ()
	close the descriptor
void	close_safe () throw ()
	close the descriptor no exception
int	read (void *buffer, size_t number) const
int	write (const void *buffer, size_t number) const
int	fd () const throw ()
	file descritptor
void	closeOnExec ()
	It flags the file descriptor to be closed after any call to the exec okssystem function.

Static Public Member Functions
static int	flags (bool read_mode, bool write_mode)

Protected Member Functions
void	open (const File *file, int flags, mode_t perm)
	internal open method

Private Attributes
int	m_fd
std::string	m_name
	internal file descriptor

Detailed Description

File descriptor / Socket wrapper.

This class represents a low level file descriptor. The descriptor is opened when the object is created. It can be close explicitely, or implicetly when the object is destroyed

Author: Matthias Wiesmann

Version: 1.0

Definition at line 34 of file Descriptor.hpp.

Constructor & Destructor Documentation

◆ Descriptor()

OksSystem::Descriptor::Descriptor	(	const File *	file,
		int	flags,
		mode_t	perm )

Definition at line 40 of file Descriptor.cpp.

                                                                           {
    ERS_ASSERT( file )
    open(file,i_flags,perm); 
} // Descriptor

◆ ~Descriptor()

OksSystem::Descriptor::~Descriptor ( )

Definition at line 45 of file Descriptor.cpp.

                                 {
    if (m_fd>=0) { 
    close_safe(); 
    } 
} //  ~Descriptor

Member Function Documentation

◆ close()

void OksSystem::Descriptor::close ( )

close the descriptor

Closes the descriptor

Parameters

file	optional pointer to the file that we close (used for pretty printing potential exceptions).

Exceptions

OksSystem::CloseFail if there is problem in the close okssystem call

Definition at line 78 of file Descriptor.cpp.

                                {
    const int status = ::close(m_fd); 
    if (status<0) {
    throw OksSystem::CloseFileIssue( ERS_HERE, errno, m_name.c_str() ); 
    } // 
    m_fd = -1 ;
} // close

◆ close_safe()

void OksSystem::Descriptor::close_safe	(		)
throw	(	)

close the descriptor no exception

Closes a descriptor safely, i.e without throwing exceptions If there is a proble, the information is sent to the warning stream

Definition at line 91 of file Descriptor.cpp.

                                             {
    const int status = ::close(m_fd); 
    if (status<0) {
    ers::warning( OksSystem::CloseFileIssue( ERS_HERE, errno, m_name.c_str() ) ); 
    } // if
} // close_safe

◆ closeOnExec()

void OksSystem::Descriptor::closeOnExec ( )

It flags the file descriptor to be closed after any call to the exec okssystem function.

Definition at line 119 of file Descriptor.cpp.

                                      {
 
  bool success = false;
  int storeErrno = 0;
 
  int oldFlags = ::fcntl(m_fd, F_GETFD);
  if(oldFlags != -1) {
    int newFlags = ::fcntl(m_fd, F_SETFD, oldFlags|FD_CLOEXEC);
    if(newFlags == -1) {
      storeErrno = errno;
    } else {
      success = true;
    }
  } else {
    storeErrno = errno;
  }  
  
  if(!success) {
    std::string eMsg = "File descriptor for file " + m_name +
      " will not be closed after exec. Reason: " + std::string(::strerror(storeErrno));
    throw OksSystem::OksSystemCallIssue(ERS_HERE, storeErrno, "fcntl", eMsg.c_str());
  }
 
}

◆ fd()

int OksSystem::Descriptor::fd	(		)	const
throw	(	)

file descritptor

Definition at line 111 of file Descriptor.cpp.

                                          { 
  return m_fd;
} 

◆ flags()

int OksSystem::Descriptor::flags	(	bool	read_mode,
		bool	write_mode )

static

Definition at line 26 of file Descriptor.cpp.

                                                              {
    if (read_mode && write_mode) { 
    return O_RDWR | O_CREAT; 
    }
    if (read_mode) {
    return O_RDONLY;
    } 
    if (write_mode) {
    return O_WRONLY | O_CREAT; 
    } 
    return 0;
} // flags

◆ open()

void OksSystem::Descriptor::open	(	const File *	file,
		int	i_flags,
		mode_t	perm )

protected

internal open method

Opens the descriptor

Parameters

file	pointer to the file to open
flags	open flags
perm	the permissions

Definition at line 62 of file Descriptor.cpp.

                                                                          {
    ERS_ASSERT( file )
    bool alreadyExists = file->exists();
    m_fd = ::open(*file,i_flags,perm);
    m_name = file->full_name();
    if (m_fd<0) throw OksSystem::OpenFileIssue( ERS_HERE, errno, m_name.c_str() );
    if((alreadyExists == false) && ((i_flags & O_CREAT) != 0)) {
      ::fchmod(m_fd, perm);
    }
} // open

◆ operator int()

OksSystem::Descriptor::operator int	(		)	const
throw	(	)

Definition at line 51 of file Descriptor.cpp.

                                                {
    return m_fd;
} // operator int()

◆ read()

int OksSystem::Descriptor::read	(	void *	buffer,
		size_t	number ) const

Definition at line 98 of file Descriptor.cpp.

                                                               {
    ssize_t status = ::read(m_fd,buffer,number);
    if (status<0) throw OksSystem::ReadIssue( ERS_HERE, errno, m_name.c_str() );
    return status;
} // read

◆ write()

int OksSystem::Descriptor::write	(	const void *	buffer,
		size_t	number ) const

Definition at line 105 of file Descriptor.cpp.

                                                                      {
    ssize_t status = ::write(m_fd,buffer,number);
    if (status<0) throw OksSystem::WriteIssue( ERS_HERE, errno, m_name.c_str() );
    return status;
} // write

Member Data Documentation

◆ m_fd

int OksSystem::Descriptor::m_fd

private

Definition at line 61 of file Descriptor.hpp.

◆ m_name

std::string OksSystem::Descriptor::m_name