Question

I can’t get to know why do I keep getting this segmentation fault in this function
Could anyone enlighten me about how to get rid of it and get my program to work…?

Lign 33 : flux = opendir(path);
Lign 98 : ret = listdir(env, stock, pos, stock->stock_name[stock->i]);

int     listdir(t_env* env, t_stock* stock, t_pos* pos, char* path)
{
        struct dirent*  dirinfo;
        DIR*            flux;

        init_xy(pos);
        cl_screen(env);

        flux = opendir(path);
        if (flux == NULL)
                return (1);
        alloc_mem(stock);
        stock->i = 0;
        while ((dirinfo = readdir(flux)))
        {
                id_strcpy(stock->stock_name[stock->i], dirinfo->d_name);               
                print_list(env, pos);
                id_print_str(stock->stock_name[stock->i]);
                pos->y = pos->y + 1;
                stock->i = stock->i + 1;
        }
        stock->i = stock->i - 1;
        pos->y = pos->y - 1;
        pos->ymax = pos->y;
        closedir(flux);
        return (0);
}

void    enter(t_env* env, t_pos* pos, t_stock* stock)
{
        int     ret;

        (void)pos;
        cl_screen(env);
        frame(env);
        ret = listdir(env, stock, pos, stock->stock_name[stock->i]);

        ret = 0;
        if (ret == 1)
        {
                free_mem(stock);
                reset_keypress();
                exit(1);
        }
        stock->i = 0;
}

(gdb) where
#0  __opendir (name=0x0) at ../sysdeps/unix/opendir.c:86
#1  0x08048ebb in listdir (env=0xbffff890, stock=0xbffff880, pos=0xbffff86c, path=0x0) at listdir.c:33
#2  0x080494ad in enter (env=0xbffff890, pos=0xbffff86c, stock=0xbffff880) at run_fct.c:98
#3  0x0804930a in press (env=0xbffff890, pos=0xbffff86c, stock=0xbffff880, arrows=0xbffff82d "\n") at run_fct.c:51
#4  0x080491db in run (env=0xbffff890, pos=0xbffff86c, stock=0xbffff880) at run_fct.c:25
#5  0x08048985 in main (argc=2, argv=0xbffff954) at main.c:35

Answer 1

Your backtrace shows that you’re passing NULL as the name parameter to opendir(). That’s not going to work. It looks like your stock data structure in enter() isn’t filled in with what you expect it to be. In particular, stock->stock_name[stock->i] is NULL at the time you make the failing call to opendir().