validator

#include <iostream>#include <string>#include <stack>#include <fstream>class text_buffer{  std::string m_text;public:  typedef std::string::const_iterator const_iterator;  const_iterator begin() const  {return m_text.begin();}  const_iterator end() const {return m_text.end();}    bool read_from_file(const std::string & file_name)  {    m_text.clear();    std::ifstream istr(file_name.c_str(),std::ios::binary);    if(!istr)      {	std::cerr << "can't open input file:" << file_name << std::endl;	return false;      }    int n = 0;    char buf[1024];    while(n = istr.readsome(buf,1024))      m_text.append(buf,buf+n);    return true;  }  };class validator{  std::string tgOpen;  std::string tgClose;public:  bool  init(const std::string & tag_file)  {    std::ifstream istr(tag_file.c_str());    if(!istr)      {	std::cerr << "can't open tag's file " << std::endl;	return false;      }    std::getline(istr,tgOpen);    std::getline(istr,tgClose);    if(tgOpen.size() != tgClose.size())      {	std::cerr << "tag's file has incorrect format" << std::endl;	return false;      }    return true;  }  void validate(const text_buffer & text)  {    bool comment = false;    std::stack<char> tags;    text_buffer::const_iterator cur = text.begin(), end = text.end();        for (;cur != end;++cur)       {	if (*cur == '!')	  comment=!comment;		if (!comment) 	  {	    if( tgOpen.find(*cur) != std::string::npos)	      {		std::cout << *cur << std::endl;		tags.push(*cur);		continue;	      }	    int n;	    if( (n = tgClose.find(*cur)) != std::string::npos)	      {	      std::cout << *cur << std::endl;	      if (!tags.empty()) 		{		  if (tgOpen[n] != tags.top())		    std::cout<<"tags error 1!"<<std::endl;		  tags.pop();		} 	      else 		{		  std::cout<<"tags error 2!"<<std::endl;		}	      }	  }      }    if (!tags.empty())       {	std::cout<<"tags error 3!"<<std::endl;      }    std::cout<<"comment: "<<comment<<std::endl;  }  };int main(int argc, char ** argv){  if(argc != 3)    {      std::cerr <<"Usage: validator <text_file> <tag_file>" << std::endl;      return 1;    }  text_buffer text;  if(!text.read_from_file(argv[1]))    {      return 1;    }  validator val;  if(!val.init(argv[2]))    {      return 1;    }  val.validate(text);  return 0;}