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test2.cpp

#include <fstream>
#include <stdlib.h>
#include <iostream>
#include <string>
#include <list>
#include <utility>
#include "diskdatabase.hpp"

using namespace std;

void error_return(const char* msg)
{
        cerr << msg;
        exit(3);
}

class mystring
{
public:
        string my;

        mystring() {}
        mystring(const string& s) : my(s) {}

        istream& read(istream& is)
        {
                size_t t;
                char *nstr;

                is.read(&t, sizeof(t));
                nstr = new char[t];
                is.read(nstr,t);
                my = string(nstr);

                delete [] nstr;
        }

        size_t DataSize() const
        {
                return sizeof(size_t) + my.length() + 1;
        }

        ostream& write(ostream& os)
        {
                size_t t;

                t = my.length() + 1;

                os.write(&t,sizeof(t));
                os.write(my.c_str(),t);
        }
};

int main(int argc, char *argv[])
{
        int i;
        ID id;
        list<ID> m;
        list<ID>::iterator p;
        DiskDatabase<mystring> ms;
        DiskDatabase<mystring> ps;
        pair<mystring,bool> ret;
        mystring s;
        fstream outfile;
        fstream infile;

        if(!ms.Create("/h/11/trokhim/work/code/Hello")) error_return("Could not create database");

        for(i=argc-1; i > 0; i--) 
        {
                s = string(argv[i]);
                id = ms.Add(s);

                cout << "ID: " << id << "       ";
                cout << "DATA: " << s.my << endl;

                m.push_back(id);
        }

        for(p = m.begin(); p != m.end(); p++)
        {
                ret = ms[*p];

                if(!ret.second) 
                        cout << "Couldn't retrieve the record from the database" << endl;
                else
                {
                        cout << "ID " << *p << "        ";
                        cout << "string " << ret.first.my << endl;
                }
        }

        cout << endl << "Here we delete all" << endl;

        ms.RemoveAll();

        for(p = m.begin(); p != m.end(); p++)
        {
                ret = ms[*p];

                if(!ret.second) 
                        cout << "Couldn't retrieve the record from the database" << endl;
                else
                {
                        cout << "ID " << *p << "        ";
                        cout << "string " << ret.first.my << endl;
                }
        }       
        m.clear();

        cout << endl << "Here we read them all again" << endl;

        for(i=argc-1; i > 0; i--) 
        {
                s = string(argv[i]);
                id = ms.Add(s);

                cout << "ID: " << id << "       ";
                cout << "DATA: " << s.my << endl;

                m.push_back(id);
        }

        for(p = m.begin(); p != m.end(); p++)
        {
                ret = ms[*p];

                if(!ret.second) 
                        cout << "Couldn't retrieve the record from the database" << endl;
                else
                {
                        cout << "ID " << *p << "        ";
                        cout << "string " << ret.first.my << endl;
                }
        }       

        cout << endl << "ANd the second time" << endl;

        for(i=argc-1; i > 0; i--) 
        {
                s = string(argv[i]);
                id = ms.Add(s);

                cout << "ID: " << id << "       ";
                cout << "DATA: " << s.my << endl;

                m.push_back(id);
        }

        for(p = m.begin(); p != m.end(); p++)
        {
                ret = ms[*p];

                if(!ret.second) 
                        cout << "Couldn't retrieve the record from the database" << endl;
                else
                {
                        cout << "ID " << *p << "        ";
                        cout << "string " << ret.first.my << endl;
                }
        }       

        cout << endl << "Here we delete all the second time" << endl;

        p = m.begin();
        for(; p != m.end(); p++) ms.Remove(*p);

        for(p = m.begin(); p != m.end(); p++)
        {
                ret = ms[*p];

                if(!ret.second) 
                        cout << "Couldn't retrieve the record from the database" << endl;
                else
                {
                        cout << "ID " << *p << "        ";
                        cout << "string " << ret.first.my << endl;
                }
        }       

        m.clear();
        
        cout << endl << "Here we read them all again" << endl;

        for(i=argc-1; i > 0; i--) 
        {
                s = string(argv[i]);
                id = ms.Add(s);

                cout << "ID: " << id << "       ";
                cout << "DATA: " << s.my << endl;

                m.push_back(id);
        }

        for(p = m.begin(); p != m.end(); p++)
        {
                ret = ms[*p];

                if(!ret.second) 
                        cout << "Couldn't retrieve the record from the database" << endl;
                else
                {
                        cout << "ID " << *p << "        ";
                        cout << "string " << ret.first.my << endl;
                }
        }

        cout << endl << "Here we write and read" << endl;

        outfile.open("/h/11/trokhim/work/code/mdtest.dat", ios::out | ios::binary);
        if(!outfile) error_return("Couldn't open output file");

        ms.Write(outfile);
        ms.Close();
        if(!outfile) error_return("couldn't write to the output file");

        outfile.close();

        infile.open("/h/11/trokhim/work/code/mdtest.dat", ios::in | ios::nocreate | ios::binary);

        if(!infile) error_return("Couldn't open input file");

        ps.Read(infile);
        if(!infile) error_return("couldn't read from input file");

        cout << "hey7" << endl;
        infile.close();
        cout << "hey8" << endl;

        for(p = m.begin(); p != m.end(); p++)
        {
                ret = ps[*p];

                if(!ret.second) 
                        cout << "Couldn't retrieve the record from the database" << endl;
                else
                {
                        cout << "ID " << *p << "        ";
                        cout << "string " << ret.first.my << endl;
                }
        }

        return 0;
}

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