fd.h

Go to the documentation of this file.

/*! \file xstream/fd.h
 *
 * \brief C++ streambuf to work with file descriptors
 *
 */

#ifndef __XSTREAM_FD_H
#define __XSTREAM_FD_H

#include <xstream/config.h>

#include <xstream/common.h>
#include <xstream/posix.h>
#include <streambuf>
#include <set>

namespace xstream{

/*!
 * \brief  file descriptor streambuf objects
 *
 */
namespace fd{

/*!
 * \brief file descriptor streambuf
 *
 * allows to use a streambuf to read/write data to/from a file descriptor
 *
 * \todo implement seek operation when possible
 *
 */
class streambuf: public xstream::ostreambuf, private xstream::posix::fd {
    private:

        xstream::buffer rbuf; /*!< were read data is stored */
        xstream::buffer wbuf; /*!< were data to be written is stored */


        /*!
         * \brief flush as much data as possible (overloaded from streambuf)
         *
         * */
        int sync();

        /*!
         * \brief write a character that surpasses buffer end (overloaded from streambuf)
         * 
         */
        int overflow(int c);

        /*!
         * \brief write an entire buffer (overloaded from streambuf)
         *
         */
        std::streamsize xsputn(const char* buffer, std::streamsize n);

        /*!
         * \brief reads \c n characters to \c buffer (overloaded from streambuf)
         *
         */
        std::streamsize xsgetn(char *buffer, std::streamsize n);

        /*!
         * \brief requests that input buffer be reloaded (overloaded from streambuf)
         */
        int underflow();

        void reset_write();

        void flush_write();
        
    public:
        /*!
         * \brief construct specifying the file descriptor
         *
         * \param fd filedescriptor
         * \param close if true closes the file descriptor at destruction
         */
        streambuf(int fd, bool close=true);

        /*!
         * \brief closes the streambuf stream
         *
         */
        ~streambuf();

};


}//namespace fd
}//namespace xstream

#endif