Why strcmp does not return 0? - c

Question

I have a small program to handle a list of rabbits (name, district, participation count) stored in an array of pointers (Rabbit** iterator). I'd like to implement the following methods: add, delete and modify a rabbit, list all the rabbits or list by district.
When I compare for example the name of the rabbits in the list with strcmp() it doesn't return 0 when the names are equal. How can I solve this problem?
The Rabbit struct:
typedef struct Rabbit {
char* name;
char* district;
unsigned part_count;
} Rabbit;
The delete method:
bool delete_rabbit(char* delete_name)
{
for (unsigned i = 0; i < size; ++i) {
if (iterator[i] != NULL && strcmp(iterator[i]->name, delete_name) == 0) {
free(iterator[i]);
iterator[i] = NULL;
count--;
return true;
}
}
return false;
}
The list by district method:
void list_by_district(char* district)
{
unsigned counter = 0;
for (unsigned i = 0; i < size; ++i) {
if (iterator[i] != NULL && strcmp(iterator[i]->district, district) == 0) {
counter++;
printf("\n%u. Rabbit:\n", counter);
printf("Name: %s\nDistrict: %s\nParticipation count: %u\n", iterator[i]->name, iterator[i]->district, iterator[i]->part_count);
}
}
}
The modify method is similar to the delete method except it only changes the values.
The corresponding code snippets from main:
Rabbit** iterator;
unsigned size = 10, count = 0;
int main()
{
iterator = (Rabbit**)malloc(sizeof(Rabbit*) * 10);
...
do {
...
switch (input) {
case 'a':
if (count == size) iterator = allocate_more_memory();
...
iterator[count++] = add_rabbit(new_name, new_district, new_part_count);
break;
case 'd':
if (size == count + 6) iterator = allocate_less_memory();
do {
printf("Enter name to be deleted: ");
scanf("%[^\n]", delete_name);
getchar();
if (strlen(delete_name) >= 30) printf("Name only has 30 or less characters!\n");
} while (strlen(delete_name) >= 30);
if (!delete_rabbit(delete_name)) printf("\nThere's no rabbit in the list with this name.\n");
break;
...
}
} while (input != 'x');
...
free(iterator);
return 0;
}
EDIT:
The add method:
Rabbit* add_rabbit(char* new_name, char* new_district, unsigned new_part_count)
{
Rabbit* new_rabbit = (Rabbit*)malloc(sizeof(Rabbit));
if (new_rabbit) {
new_rabbit->name = (char*)malloc((strlen(new_name) + 1) * sizeof(char));
new_rabbit->district = (char*)malloc((strlen(new_district) + 1) * sizeof(char));
strcpy(new_rabbit->name, new_name);
strcpy(new_rabbit->district, district);
new_rabbit->part_count = new_part_count;
}
return new_rabbit;
}
The allocate less memory method:
Rabbit** allocate_less_memory()
{
Rabbit** new_iterator = (Rabbit**)malloc(sizeof(Rabbit*) * (size - 5));
if (new_iterator) {
unsigned counter = 0;
for (unsigned i = 0; i < size; ++i) {
if (iterator[i] != NULL) {
new_iterator[counter++] = iterator[i];
}
}
size -= 5;
free(iterator);
return new_iterator;
}
return NULL;
}