Ttykuu

The nodes seems to connect just fine until implementing my getName() function for variable assignment:

> *** Error in `./zBunny.exe': free(): invalid pointer: 0x00007f0e528dab78 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x777e5)[0x7f0e5258d7e5]
/lib/x86_64-linux-gnu/libc.so.6(+0x8037a)[0x7f0e5259637a]
/lib/x86_64-linux-gnu/libc.so.6(cfree+0x4c)[0x7f0e5259a53c]
./zBunny.exe[0x4016e8]
./zBunny.exe[0x401ef2]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf0)[0x7f0e52536830]
./zBunny.exe[0x401569]
======= Memory map: ========
00400000-00404000 r-xp 00000000 08:10 33423400 /media/keifer/Storage/cppProjects/examples/bunny/zBunny.exe
00604000-00605000 r--p 00004000 08:10 33423400 /media/keifer/Storage/cppProjects/examples/bunny/zBunny.exe
00605000-00606000 rw-p 00005000 08:10 33423400 /media/keifer/Storage/cppProjects/examples/bunny/zBunny.exe
01f52000-01f84000 rw-p 00000000 00:00 0 [heap]
7f0e4c000000-7f0e4c021000 rw-p 00000000 00:00 0 
7f0e4c021000-7f0e50000000 ---p 00000000 00:00 0 
7f0e5220d000-7f0e52315000 r-xp 00000000 fc:01 5509816 /lib/x86_64-linux-gnu/libm-2.23.so
7f0e52315000-7f0e52514000 ---p 00108000 fc:01 5509816 /lib/x86_64-linux-gnu/libm-2.23.so
7f0e52514000-7f0e52515000 r--p 00107000 fc:01 5509816 /lib/x86_64-linux-gnu/libm-2.23.so
7f0e52515000-7f0e52516000 rw-p 00108000 fc:01 5509816 /lib/x86_64-linux-gnu/libm-2.23.so
7f0e52516000-7f0e526d6000 r-xp 00000000 fc:01 5509806 /lib/x86_64-linux-gnu/libc-2.23.so
7f0e526d6000-7f0e528d6000 ---p 001c0000 fc:01 5509806 /lib/x86_64-linux-gnu/libc-2.23.so
7f0e528d6000-7f0e528da000 r--p 001c0000 fc:01 5509806 /lib/x86_64-linux-gnu/libc-2.23.so
7f0e528da000-7f0e528dc000 rw-p 001c4000 fc:01 5509806 /lib/x86_64-linux-gnu/libc-2.23.so
7f0e528dc000-7f0e528e0000 rw-p 00000000 00:00 0 
7f0e528e0000-7f0e528f6000 r-xp 00000000 fc:01 5509743 /lib/x86_64-linux-gnu/libgcc_s.so.1
7f0e528f6000-7f0e52af5000 ---p 00016000 fc:01 5509743 /lib/x86_64-linux-gnu/libgcc_s.so.1
7f0e52af5000-7f0e52af6000 rw-p 00015000 fc:01 5509743 /lib/x86_64-linux-gnu/libgcc_s.so.1
7f0e52af6000-7f0e52c68000 r-xp 00000000 fc:01 3670249 /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21
7f0e52c68000-7f0e52e68000 ---p 00172000 fc:01 3670249 /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21
7f0e52e68000-7f0e52e72000 r--p 00172000 fc:01 3670249 /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21
7f0e52e72000-7f0e52e74000 rw-p 0017c000 fc:01 3670249 /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21
7f0e52e74000-7f0e52e78000 rw-p 00000000 00:00 0 
7f0e52e78000-7f0e52e9e000 r-xp 00000000 fc:01 5509685 /lib/x86_64-linux-gnu/ld-2.23.so
7f0e53073000-7f0e53079000 rw-p 00000000 00:00 0 
7f0e5309c000-7f0e5309d000 rw-p 00000000 00:00 0 
7f0e5309d000-7f0e5309e000 r--p 00025000 fc:01 5509685 /lib/x86_64-linux-gnu/ld-2.23.so
7f0e5309e000-7f0e5309f000 rw-p 00026000 fc:01 5509685 /lib/x86_64-linux-gnu/ld-2.23.so
7f0e5309f000-7f0e530a0000 rw-p 00000000 00:00 0 
7ffe1d800000-7ffe1d821000 rw-p 00000000 00:00 0 [stack]
7ffe1d9b0000-7ffe1d9b2000 r--p 00000000 00:00 0 [vvar]
7ffe1d9b2000-7ffe1d9b4000 r-xp 00000000 00:00 0 [vdso]
ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
Aborted

This program is acting as a template for what will be a linked list of bunny objects with unique names and features.

 int Nodes::insert()
 


 Node* new_node = (Node*) malloc(sizeof(Node));

 new_node->name = getName();

 new_node->prev = NULL;
 new_node->next = head;

 if (head != NULL)
 
 head->prev = new_node;
 

 head = new_node;

 return 0;
 

I've designed it so that ideally when a new node is made the each variable has relevant data assigned from a function call. For example:

new_node->name = getName();

In the instance of my memory issue the first node created runs fine but the second one produces the error at this^ function call assignment.

The full code:

#include<iostream>
#include<fstream>
#include<vector>
#include<string>

using std::vector;
using std::string;
using std::cout;
using std::endl;


class Node

 public:
 int data;
 string name;

 Node* next;
 Node* prev;
;



class Nodes
 private:
 Node* head = NULL;

 public:
 int insert(); 
 void display();
 int randomGen(int n);
 string getName();
 void extract(std::vector<string> *vect, string fileName);

;



void Nodes::display()

 Node* next = head;

 while(next != NULL)
 
 cout << next->name << 'n';
 next = next->next;
 




int Nodes::insert()

 Node* new_node = (Node*) malloc(sizeof(Node));

 new_node->name = getName();

 new_node->prev = NULL;
 new_node->next = head;

 if (head != NULL)
 
 head->prev = new_node;
 

 head = new_node;

 return 0;



int Nodes::randomGen(int n) 

 srand((int)time(0));

 return (rand() % n) + 1;



// --
void Nodes::extract(vector<string> *vect, string fileName)//pulls lines from a file and splits the names up from each line using tokenization indexing them for use


 std::ifstream accessFile;
 accessFile.open (fileName);

 string pulledLine;

 if (accessFile.is_open())
 

 string extractedName;

 getline(accessFile, pulledLine);

 for(auto p: pulledLine)
 

 if(p != ' ')
 
 if(extractedName != " ")
 
 extractedName += p;
 

 else 

 extractedName = p; 
 ;

 

 else 

 vect->push_back(extractedName);
 extractedName = " "; 
 
 

 



string Nodes::getName()//utilizes extract() to pull names and combines them using randomGen() to pull a name from a random index.


 std::vector<string> fNames = " ";
 std::vector<string> lNames = " ";

 const string fileName[2] = "fnames.txt", "lnames.txt";

 extract(&fNames, fileName[0]); 
 extract(&lNames, fileName[1]);


 /* original formula for pulling random names

 string fullName = fNames[randomGen(sizeof(fNames))] + " " + lNames[randomGen(sizeof(lNames))];

 */


 //put here so I could focus on memory leak.
 string fullName = "cjaz"; 


 return fullName; 

// --

int main()

 Nodes control;
 control.insert();
 control.insert();
 // control.insert();
 // control.insert();

 control.display();

I'm looking to figure out the source of this memory issue and bring to light any bad practices or design flaws that I might be using.

Any and all feedBack is appreciated, Thank you!