// -*- C++ -*-// $Id: reader.h,v 1.13 2002/07/02 22:10:57 t1mpy Exp $// id3lib: a software library for creating and manipulating id3v1/v2 tags// Copyright 1999, 2000  Scott Thomas Haug// This library is free software; you can redistribute it and/or modify it// under the terms of the GNU Library General Public License as published by// the Free Software Foundation; either version 2 of the License, or (at your// option) any later version.//// This library is distributed in the hope that it will be useful, but WITHOUT// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public// License for more details.//// You should have received a copy of the GNU Library General Public License// along with this library; if not, write to the Free Software Foundation,// Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.// The id3lib authors encourage improvements and optimisations to be sent to// the id3lib coordinator.  Please see the README file for details on where to// send such submissions.  See the AUTHORS file for a list of people who have// contributed to id3lib.  See the ChangeLog file for a list of changes to// id3lib.  These files are distributed with id3lib at// http://download.sourceforge.net/id3lib/#ifndef _ID3LIB_READER_H_#define _ID3LIB_READER_H_#include "id3/globals.h" //has <stdlib.h> "id3/sized_types.h"class ID3_CPP_EXPORT ID3_Reader{ public:  typedef uint32 size_type;  typedef uint8  char_type;  typedef uint32 pos_type;  typedef  int32 off_type;  typedef  int16 int_type;  static const int_type END_OF_READER;    /** Close the reader.  Any further actions on the reader should fail.   **/  virtual void close() = 0;  /** Return the beginning position in the reader */  virtual pos_type getBeg() { return static_cast<pos_type>(0); }  /** Return the ending position in the reader */  virtual pos_type getEnd() { return static_cast<pos_type>(-1); }  /** Return the current position in the reader */  virtual pos_type getCur() = 0;  /** Set the value of the current position for reading.   **/  virtual pos_type setCur(pos_type pos) = 0;  /**   ** Read a single character and advance the internal position.  Note that the   ** interal position may advance more than one byte for a single character    ** read.  Returns END_OF_READER if there isn't a character to read.   **/  virtual int_type readChar()   {    if (this->atEnd())    {       return END_OF_READER;     }    char_type ch;    this->readChars(&ch, 1);    return ch;  }  /**   ** Return the next character to be read without advancing the internal    ** position.  Returns END_OF_READER if there isn't a character to read.   **/  virtual int_type peekChar() = 0;    /** Read up to \c len characters into buf and advance the internal position   ** accordingly.  Returns the number of characters read into buf.  Note that   ** the value returned may be less than the number of bytes that the internal   ** position advances, due to multi-byte characters.   **/  virtual size_type readChars(char_type buf[], size_type len) = 0;  virtual size_type readChars(char buf[], size_type len)  {    return this->readChars(reinterpret_cast<char_type *>(buf), len);  }    /** Skip up to \c len chars in the stream and advance the internal position   ** accordingly.  Returns the number of characters actually skipped (may be    ** less than requested).   **/  virtual size_type skipChars(size_type len)  {    const size_type SIZE = 1024;    char_type bytes[SIZE];    size_type remaining = len;    while (!this->atEnd() && remaining > 0)    {      remaining -= this->readChars(bytes, (remaining < SIZE ? remaining : SIZE));    }    return len - remaining;  }  virtual size_type remainingBytes()  {    pos_type end = this->getEnd(), cur = this->getCur();    if (end == pos_type(-1))    {      return size_type(-1);    }        if (end >= cur)    {      return end - cur;    }        return 0;  }    virtual bool atEnd() { return this->getCur() >= this->getEnd(); }};#endif /* _ID3LIB_READER_H_ */