printing fields of structure in c (dynamic memory allocation) - c

Question

I'm a noob at C and create this program to help me learn. Purpose is to add soccer players to a team and print info.
I'm trying to print fields of my club structure but when my program gets to my print method, all my values are garbage or addresses. How can I get "real" values
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define SIZE 8
typedef struct player {
int id;
char *position;
} Player;
typedef struct club {
int size;
Player *team[SIZE];
} Club;
Player *create_player(int id, const char *description);
void create_team(Club *club);
void print_club(const Club *club);
void add_player_to_club(Club *club, int id, const char *position);
int main() {
Club club;
create_team(&club);
add_player_to_club(&club, 1, "forward");
add_player_to_club(&club, 2, "goalie");
print_club(&club);
return 0;
}
Player *create_player(int id, const char *description){
Player *player;
player = malloc(sizeof(Player));
if(description == NULL){
player->position = NULL;
} else {
player->position = malloc(strlen(description) + 1);
strcpy(player->position, description);
player->id = id;
}
return player;
}
void create_team(Club *team){
team = malloc(sizeof(Club));
if (team == NULL) {
return;
} else {
team->size = 0;
}
}
void print_club(const Club *club) {
int i = 0;
if (club == NULL) {
return;
} else if (club->size == 0) {
printf("No team members\n");
} else {
for (i = 0; i < SIZE; i++) {
printf("Id: %d Position: %s\n", club->team[i]->id,
club->team[i]->position);
}
}
}
void add_player_to_club(Club *club, int id, const char *position){
if (club == NULL || club->size >= SIZE) {
return;
} else {
Player player = *create_player(id, position);
club->team[club->size -1] = &player;
}
}
Here's a pic of my debugging session
Debugger

Answer 1

Problem 1
create_team is not doing anything useful for main. You are changing the value of a function local variable. As a consequence club remains uninitialized in main. You proceed to use it as though it is valid object, which is cause for undefined behavior.
You can change that function to:
void create_team(Club *team){
team->size = 0;
for (int i = 0; i < SIZE; ++i )
{
team->team[i] = NULL; // Unfortunate choice of variable names
// but should be OK.
}
}
Problem 2
You are storing a pointer to a function local variable in add_player_to_club. That pointer becomes invalid the function returns.
Player player = *create_player(id, position);
club->team[club->size -1] = &player; // Problem
Change it to:
club->team[club->size] = create_player(id, position);
club->size++;
Problem 3
You are printing too may Players in print_club. There aren't always SIZE number of Players in the team. Change the line
for (i = 0; i < SIZE; i++) {
to
for (i = 0; i < club->size; i++) {