Memory Leak in Dynamic 3 dimensional array of CString - c++

Question

I am working with a dynamic declaration of a 3 dimensional array of type CString. (I know, why CString again? Use vectors! I can't, the assignment requires use of cstring.)
So the assignment is to make a user defined playlist of songs which allows adding, removing, displaying, and searching. Also, the playlist must save to a text file called songs.txt.
My problem is I keep getting memory leaks in my adding function I will share all code and memory leak errors, so you can see.
Valgrind Errors:
==17401== HEAP SUMMARY:
==17401== in use at exit: 73,519 bytes in 31 blocks
==17401== total heap usage: 36 allocs, 5 frees, 91,199 bytes allocated
==17401==
==17401== 1 bytes in 1 blocks are definitely lost in loss record 1 of 12
==17401== at 0x4C284B7: operator new[](unsigned long) (in
/usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==17401== by 0x401BB3: songlist::readList(std::basic_ifstream<char,
std::char_traits<char> >&)
The rest just kind of repeats itself through 12 of 12
My code:
defs.cpp:
#includes <iostream>
#include <cstring>
#include <iomanip>
#include <fstream>
#include "proj4.h"
using namespace std;
void songlist::makeList()
{
MAX_TRAX = 0;
song = new char**[20];
for (int i=0; i<20; i++)
{
song[i] = new char*[5];
}
}
void songlist::readList(ifstream& infile)
{
int counter = 0;
if (!infile.is_open())
{
cout << "Cannot open file: songs.txt";
}
while(!infile.eof())
{
infile >> newSong.title >> newSong.artist >>
newSong.durationMin >> newSong.durationSec >> newSong.album;
int i = strlen(newSong.title);
i++;
int j = strlen(newSong.artist);
j++;
int k = strlen(newSong.durationMin);
k++;
int l = strlen(newSong.durationSec);
l++;
int m = strlen(newSong.album);
m++;
if(i>0)
{
song[counter][0]= new char[i];
song[counter][1]= new char[j];
song[counter][2]= new char[k];
song[counter][3]= new char[l];
song[counter][4]= new char[m];
song[counter][0] = newSong.title;
song[counter][1] = newSong.artist;
song[counter][2] = newSong.durationMin;
song[counter][3] = newSong.durationSec;
song[counter][4] = newSong.album;
counter++;
}
MAX_TRAX = counter-1;
}
counter = 0;
}
void songlist::saveList(ofstream& outfile)
{
if (!outfile.is_open())
{
cout << "Cannot find file: songs.txt";
}
for (int i=0; i<=MAX_TRAX; i++)
{
outfile << song[i][0] << "; " << song[i][1] << "; " << song[i]
[2] << "; " <<song[i][3] << "; " << song[i][4] << ";" << endl;
}
}
void songlist::displayList()const
{
cout << left << setw(16) << '#' << left << setw(30) << "Song Name" <<
left << setw(22) << "Artist Name" << left << setw(17) << "Duration" <<
left << setw(20) << "Album Title" << endl;
cout << left << setw(110) << setfill ('-') << '-' << endl;
cout << setfill (' ');
if (strlen(newSong.title)>=1)
{
for (int i=0; i<=MAX_TRAX; i++)
{
cout << left << setw(4) << i+1 << left << setw(31) <<
song[i][0] << left << setw(31) << song[i][1] << right << setw(4) << song[i]
[2]
<< ':';
if (strlen(song[i][3])==1)
{
cout << '0';
cout << left << setw(3) << song[i][3] <<
left << setw(3) << song[i][4] << endl;
}
else
cout << left << setw(4) << song[i][3] << left <<
setw(3) << song[i][4] << endl;
}
cout << left << setw(110) << setfill ('-') << '-' << endl;
cout << setfill (' ');
}
}
void songlist::addSong()
{
if(strlen(newSong.title)>=1)
{
MAX_TRAX++;
}
cout << "Add a Song" << endl;
cout << endl;
cout << "Enter Song Title: ";
cin.ignore();
cin.get(newSong.title, 30);
cout << endl;
cout << "Enter Artist Name: ";
cin.ignore();
cin.get(newSong.artist, 30);
cout << endl;
cout << "Enter Track Duration";
cout << endl;
cout << "Minutes: ";
cin.ignore();
cin.get(newSong.durationMin, 3);
cout << endl;
cout << "Seconds: ";
cin.ignore();
cin.get(newSong.durationSec, 3);
cout << endl;
cout << "Enter Album Title: ";
cin.ignore();
cin.get(newSong.album, 30);
cout << endl;
cout << "Song Added to Database!";
cout << endl;
cout << endl;
int i = strlen(newSong.title);
i++;
int j = strlen(newSong.artist);
j++;
int k = strlen(newSong.durationMin);
k++;
int l = strlen(newSong.durationSec);
l++;
int m = strlen(newSong.album);
m++;
song[MAX_TRAX][0]= new char[i];
song[MAX_TRAX][1]= new char[j];
song[MAX_TRAX][2]= new char[k];
song[MAX_TRAX][3]= new char[l];
song[MAX_TRAX][4]= new char[m];
song[MAX_TRAX][0] = newSong.title;
song[MAX_TRAX][1] = newSong.artist;
song[MAX_TRAX][2] = newSong.durationMin;
song[MAX_TRAX][3] = newSong.durationSec;
song[MAX_TRAX][4] = newSong.album;
}
void songlist::removeSong()
{
int p = 0;
int q = 0;
int n = 0;
cout << "Remove a Song" << endl;
cout << "Enter Track Number to Confirm Deletion: ";
cin >> n;
cout << endl;
while (!(n >=1 && n <= MAX_TRAX+1))
{
cin.clear();
cin.ignore();
cout << "Must be a number between 1 and " << MAX_TRAX+1 << endl;
cout << "Enter Track Number to Confirm Deletion: ";
cin >> n;
cout << endl;
}
n--;
for (p=n;p<MAX_TRAX; p++)
{
for(q=0;q<5;q++)
{
delete[] song[p][q];
}
int i = strlen(song[p+1][0]);
i++;
int j = strlen(song[p+1][1]);
j++;
int k = strlen(song[p+1][2]);
k++;
int l = strlen(song[p+1][3]);
l++;
int m = strlen(song[p+1][4]);
m++;
song[p][0] = new char[i];
song[p][1] = new char[j];
song[p][2] = new char[k];
song[p][3] = new char[l];
song[p][4] = new char[m];
song[p][0] = song[p+1][0];
song[p][1] = song[p+1][0];
song[p][2] = song[p+1][0];
song[p][3] = song[p+1][0];
song[p][4] = song[p+1][0];
}
MAX_TRAX--;
n++;
cout << "Track Number " << n << " Deleted" << endl;
}
void songlist::searchList()const
{
int i;
char aOrB;
int counter = 0;
char art[30];
char alb[30];
cout << "Search by (a)rtist or al(b)um? (a or b): ";
cin >> aOrB;
cout << endl;
if (aOrB != 'a' && aOrB != 'b')
{
cout << "(a or b): ";
cin >> aOrB;
cout << endl;
}
if (aOrB == 'a')
{
cout << "Artist Name: ";
cin.ignore();
cin.get(art, 30);
for(i=0; i<=(MAX_TRAX); i++)
{
if (strcmp(art, song[i][1])==0)
{
cout << left << setw(2) << i+1 << left <<
setw(32) << song[i][0] << left << setw(32) << song[i][1] << right << setw(4)
<< song[i][2] << ':' << left << setw(5) << song[i][3] << left << setw(32) <<
song[i][4] << endl;
counter++;
}
}
}
else
{
cout << "Album Name: ";
cin.ignore();
cin.get(alb, 30);
for(i=0; i<=(MAX_TRAX); i++)
{
if (strcmp(alb, song[i][4])==0)
{
cout << left << setw(2) << i+1 << left <<
setw(32) << song[i][0] << left << setw(32) << song[i][1] << right << setw(4)
<<
song[i][2] << ':' << left << setw(5) << song[i][3] << left << setw(32) <<
song[i][4] << endl;
counter++;
}
}
}
if (!counter)
{
cout << endl;
cout << "No Matches Found; check spelling and/or case." << endl;
}
}
void songlist::deleteAll()
{
for(int i=0; i>=20; i++)
{
for (int j=0; j<5; j++)
delete[] song[i][j];
delete[] song[i];
}
delete[] song;
}
songlist::songlist()
{
}
Proj4.h:
#ifndef PROJ3_H
#define PROJ3_H
#include <iostream>
#include <fstream>
#include <cstring>
#include <iomanip>
using namespace std;
class songlist
{
public:
void readList(ifstream& infile);
void saveList(ofstream& outfile);
void displayList() const;
void makeList();
void addSong();
void removeSong();
void searchList() const;
void deleteAll();
songlist();
private:
struct songs
{
char title[30] = {'\0'};
char artist[30] = {'\0'};
int intMin = 0;
int intSec = 0;
char durationMin[3] = {'\0'};
char durationSec[3] = {'\0'};
char album[30] = {'\0'};
};
songs newSong;
int MAX_TRAX;
char *** song;
};
#endif
app.cpp:
#include <iostream>
#include <cstring>
#include <iomanip>
#include <fstream>
#include "proj4.h"
using namespace std;
int main()
{
char selection;
cout << endl;
cout << "*Music Track Database*" << endl;
ifstream infile;
ofstream outfile;
infile.open("songs.txt");
outfile.open("songs.txt");
songlist newlist;
newlist.makeList();
do
{
cout << endl;
cout << "Main Menu:" << endl;
cout << endl;
cout << "(a)dd a song" << endl;
cout << "(r)emove a song" << endl;
cout << "(d)isplay track listings" << endl;
cout << "(s)earch for a track" << endl;
cout << "(q)uit" << endl;
cout << endl;
cout << "Select (a, r, d, s, q): ";
cin >> selection;
cout << endl;
if (selection != 'a' && selection != 'r' && selection != 'd'
&& selection != 's' && selection != 'q')
{
cout << "Select (a, r, d, s, q): ";
cin >> selection;
cout << endl;
}
switch (selection)
{
case 'a':
newlist.readList(infile);
newlist.addSong();
newlist.saveList(outfile);
break;
case 'd':
newlist.readList(infile);
newlist.displayList();
break;
case 'r':
newlist.removeSong();
newlist.saveList(outfile);
break;
case 's':
newlist.readList(infile);
newlist.searchList();
break;
}
}while (selection != 'q');
newlist.deleteAll();
cout << "Happy Trails To You; Until We Meet Again!" << endl;
cout << endl;
infile.close();
outfile.close();
return 0;
}
Also here is a simple makefile to test it:
all:
g++ app.cpp proj4.h defs.cpp -o proj4;
clean:
clean make;
Anything helps!
Thank You in advance.

Answer 1

You're not even allowed to use structs or classes? When you become a three star programmer it's usually very bad.
Your allocations are off by one (null termination...)
But the actual leak is here. Just think what this does:
song[p][0] = new char[i];
song[p][1] = new char[j];
song[p][2] = new char[k];
song[p][3] = new char[l];
song[p][4] = new char[m];
song[p][0] = song[p+1][0];
song[p][1] = song[p+1][0];
song[p][2] = song[p+1][0];
song[p][3] = song[p+1][0];
song[p][4] = song[p+1][0];
You first allocate memory and then throw the pointers away by assigning something else to those pointers. You can never get them back and that's a leak.

Answer 2

Instead of this:
song[counter][0] = new char[i];
song[counter][1] = new char[j];
song[counter][2] = new char[k];
song[counter][3] = new char[l];
song[counter][4] = new char[m];
song[counter][0] = newSong.title;
song[counter][1] = newSong.artist;
song[counter][2] = newSong.durationMin;
song[counter][3] = newSong.durationSec;
song[counter][4] = newSong.album;
Maybe Something more like:
song[counter][0] = new char[i];
song[counter][1] = new char[j];
song[counter][2] = new char[k];
song[counter][3] = new char[l];
song[counter][4] = new char[m];
strncpy(song[counter][0], newSong.title, i);
strncpy(song[counter][0], newSong.artist, j);
strncpy(song[counter][0], newSong.durationMin, k);
strncpy(song[counter][0], newSong.durationSec, l);
strncpy(song[counter][0], newSong.album, m);