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POSingly Linked List struct insert/delete multiple free
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copied!<p>Been looking at this code for too long and I am getting gloomy any chance of figuring it out by myself has been lost :( anyone can tell me where am I being stupid? I just don't understand where I am double freeing or possibly allocating incorrectly (which I must bee doing but yeah). I keep getting <strong>* glibc detected *</strong> free(): invalid next size</p> <p>Am I actually freeing more than I need to or am I just not allocating what I need to allocate in the first place. --sorry for bad indentation can't get this editor to indent correctly</p> <p>I have structures:</p> <pre><code>typedef int boolean; typedef char * String; typedef struct { char name[30]; long ID; char address[40]; char city[20]; int age; }Employee; typedef struct node { Employee *anEmployee; struct node *next; }NODE; typedef struct { NODE *head, *tail; }SLL; </code></pre> <p>insert function--SLL (Singly Linked List)</p> <pre><code>void insert(SLL *list, Employee e){ printf("insert"); NODE *temp, *current; temp = (NODE *)malloc(sizeof(NODE)); assert(temp != NULL); temp -> anEmployee = (Employee *)malloc(sizeof(Employee *)); assert(temp -> anEmployee != NULL); strcpy(temp -> anEmployee -> name, e.name); temp -> anEmployee -> ID = e.ID; strcpy(temp -> anEmployee -> address, e.address); strcpy(temp -> anEmployee -> city, e.city); temp -> anEmployee -> age = e.age; if (list -> head == NULL) { /* list is empty */ list -> head = list -> tail = temp; return; } else { // list is not empty list -> tail -> next = temp; list -> tail = temp; } } </code></pre> <p>deleting and freeing memory in delete function as such</p> <pre><code>boolean delete(SLL *list, String str){ printf("delete"); NODE *temp, *temp2; if (list -> head == NULL) return FALSE; // list is empty temp = list -> head; while ((temp != NULL) && (strcmp(temp -> anEmployee -> name , str) != 0)) temp = temp -> next; if (temp == NULL) return FALSE; // str is not found in the list // now temp points to the NODE with str in it. Let us delete it // from the list if ( list -> head == temp) { // temp points to the first NODE if (temp -> next == NULL) { // temp points to the only NODE list -> head = list -> tail = NULL; free(temp -> anEmployee); free(temp); return TRUE; } // temp points to the first NODE but it is not the only NODE list -> head = temp -> next; free(temp -> anEmployee); free(temp); return TRUE; } if (temp -> next == NULL) { // temp points to the last NODE temp = list -> head; temp2 = list -> head -> next; while(temp2 - > next != NULL){ temp = temp->next; temp2 = temp2 ->next; } list -> tail = temp ; list -> tail -> next = NULL; free(temp2 -> anEmployee); free(temp2); return TRUE; } // temp points to some NODE in the middle of the list temp2 = temp -> next; while(temp2 - > next != NULL){ temp ->anEmployee = temp2 - > anEmployee // temp = temp->next; temp2 = temp2 ->next; } temp ->anEmployee = temp2 - > anEmployee list -> tail = temp ; list -> tail -> next = NULL; free(temp2 -> anEmployee); free(temp2); return TRUE; } </code></pre>

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