C : Linked list value lost during execution - c

Question

I am actually trying to implement a breadth-first-search algorithm in C, as an input I take any graph from a file and store all nodes and vertices in a structure.
Then I create an adjacency matrix, and run through all columns, push encountered nodes on a stack, pop them and so on till I have all the paths.
Still I have problems storing those paths in a linked list, and by problem I mean that sometimes, from some specific cases, I lose the last value of my stored path (one int array per link), which is quite surprising as it occurs only on paths of length 5 (I cannot test all lengths but up to 12 it seems OK).
It's weird, because these values are lost at function exit (I tried debugging using LLDB and in the function that creates the link, the last byte exists, but once I leave the function, it does not) and not all the time (1 out 10 execution all is fine).
To me this is a malloc issue, so I checked every single malloc of my program in order to solve (unsuccessfully) the problem. Checked all the variables and all seems fine, except for this 5 length case (I assume my program has a 'defect' that is only apparent in this case, but why ?).
I would gladly accept some help, as I just ran out of things to check.
Here is the code of the main BFS function :
void bfs(t_lemin *e)
{
t_path *save;
//set needed variables
set_bfs_base_var(e);
save = e->p;
while (paths_remain(e))
{
//Special Start-End case
if (e->map[e->nb_start][e->nb_end] == 1)
{
create_single(e);
break ;
}
e->x = e->nb_start;
reset_tab(e);
while (e->x != e->nb_end)
{
e->y = 0;
while (e->y < e->nb_rooms)
{
if (e->map[e->x][e->y] == 1 && !e->visited[e->y])
##push_on_stack the nodes
push_stack(e);
e->y++;
}
//go_to first elem on stack
e->x = e->stack[0];
if (e->x == e->nb_end || is_stack_empty(e->stack, e->nb_rooms - 1))
break ;
e->visited[e->x] = 1;
//set_it as visited than pop it
pop_stack(e, e->nb_rooms);
}
if (is_stack_empty(e->stack, e->nb_rooms - 1))
break ;
e->find_new[add_path(e)] = 1;
discover_more_paths(e, save);
}
print_paths(e, save);
e->p = save;
}
And here the 2 functions that stores the paths in a linked list :
void create_path(t_lemin *e, int *pa, int len)
{
int j;
j = 1;
//create_new_node if required
if (e->p->path)
{
if (!(e->p->next = malloc(sizeof(t_path))))
return ;
e->p = e->p->next;
}
//create_the_array_for_path_storing
e->p->path = malloc(sizeof(int) * len + 2);
e->p->next = NULL;
e->p->size_path = len + 2;
//copy_in_it
while (--len >= 0)
{
e->p->path[j++] = pa[len];
}
//copy_end_and_start_at_end_and_start
e->p->path[e->p->size_path - 1] = e->nb_end;
e->p->path[0] = e->nb_start;
e->nb_paths++;
}
int add_path(t_lemin *e)
{
int i;
int save;
int *path;
int next_path;
i = 0;
if (!(path = malloc(sizeof(int) * e->nb_rooms)))
exit(-1);
save = e->nb_end;
//in_order_to_save_the_path_i store the previous value of each node so I can find the path by iterating backward
next_path = -1;
while (e->prev[save] != e->nb_start)
{
path[i] = e->prev[save];
save = e->prev[save];
next_path = next_path == -1 && get_nb_links(e, path[i])
> 2 ? path[i] : -1;
i++;
}
//path_contains all values of the path except for start and end
save = i;
while (i < e->nb_rooms)
{
path[i] = 0;
i++;
}
create_path(e, path, save);
i = next_path == -1 ? path[0] : next_path;
//ft_printf("to_block : %d\n", i);
return (next_path == -1 ? path[0] : next_path);
}
If needed here is a clone of the entire repository, the issue can be seen running the program with maptest in the main directory : https://github.com/Caribou123/bfs_agesp.git
Make && ./lem_in < maptest
All paths must end by the last room, whereas in this case the value of the last room becomes 0. So the program outputs "start->room1->room2->....->start as the index value of start is 0.
Here is a look at my 'e', the main structure. (it's quite huge, don't be scared) :
typedef struct s_lemin
{
int x;
int y;
char *av;
int nb_ants;
int st;
int nd;
int nb_rooms;
int nb_paths;
int max_sizep;
int nb_links;
int nb_start;
int nb_end;
int **map;
int *stack;
int *visited;
int *prev;
int *find_new;
int maxy;
int maxx;
int minx;
int conti;
int miny;
char ***saa;
struct s_rooms *r;
struct s_ants *a;
struct s_rooms **table_r;
struct s_links *l;
struct s_hash **h;
struct s_rooms *start;
struct s_rooms *end;
struct s_info *i;
struct s_path *p;
struct s_path *select_p;
}
Thank you in advance for your help, and sorry if it's some stupid malloc that I somehow missed.
Artiom