xref: /trunk/main/autodoc/inc/cosv/bstream.hxx (revision 11c03c6d381fea19f0fea13ae5a371ba50bad241)

/**************************************************************
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
 *************************************************************/



#ifndef CSV_BSTREAM_HXX
#define CSV_BSTREAM_HXX

#include <string.h>
#include <cosv/string.hxx>


namespace csv
{


enum seek_dir
{
    beg = 0,
    cur = 1,
    end = 2
};


class bistream
{
  public:
    // LIFECYCLE
    virtual             ~bistream() {}

    //  OPERATIONS
        /// @return Number of actually read bytes.
    uintt               read(
                            void *          out_pDest,
                            uintt           i_nNrofBytes);
    // INQUIRY
        /**  @return True, if already one try to read had failed.
             There is no guarantee, that it returns true, if end of data
             is just reached.
             Though it will return false, if there is still somemething
             to read.
        */
    bool                eod() const;

  private:
    virtual uintt       do_read(
                            void *          out_pDest,
                            uintt           i_nNrofBytes) = 0;
    virtual bool        inq_eod() const = 0;
};


class bostream
{
  public:
    // LIFECYCLE
    virtual             ~bostream() {}

    //  OPERATIONS
        /// @return Number of actually written bytes.
    uintt               write(
                            const void *    i_pSrc,
                            uintt           i_nNrofBytes);
        /// @return Number of actually written bytes.
    uintt               write(
                            const char *    i_pSrc );
        /// @return Number of actually written bytes.
    uintt               write(
                            const String &  i_pSrc );
  private:
    virtual uintt       do_write(
                            const void *    i_pSrc,
                            uintt           i_nNrofBytes) = 0;
};


class bstream : public bistream,
                public bostream
{
  public:
    uintt               seek(
                            intt            i_nDistanceFromBegin,
                            seek_dir        i_eStartPoint = ::csv::beg );
    uintt               position() const;

  private:
    virtual uintt       do_seek(
                            intt            i_nDistance,
                            seek_dir        i_eStartPoint = ::csv::beg ) = 0;
    virtual uintt       inq_position() const = 0;
};


// IMPLEMENTATION
inline uintt
bistream::read( void *         o_pDest,
               uintt           i_nNrofBytes)
    { return do_read(o_pDest, i_nNrofBytes); }
inline bool
bistream::eod() const
    { return inq_eod(); }

inline uintt
bostream::write( const void *   i_pSrc,
                 uintt          i_nNrofBytes)
    { return do_write( i_pSrc, i_nNrofBytes ); }
inline uintt
bostream::write( const char * i_sSrc )
    { return write( i_sSrc, strlen(i_sSrc) ); }
inline uintt
bostream::write( const String & i_sSrc )
    { return write( i_sSrc.c_str(), i_sSrc.length() ); }

inline uintt
bstream::seek( intt     i_nDistance,
               seek_dir i_eStartPoint )
    { return do_seek( i_nDistance, i_eStartPoint ); }
inline uintt
bstream::position() const
    { return inq_position(); }



}   // namespace csv


#endif