Function nxtask_setup_fork

sched/task/task_fork.c:96–265

 ****************************************************************************/

FAR struct tcb_s *nxtask_setup_fork(start_t retaddr)
{
  FAR struct tcb_s *ptcb = this_task();
  FAR struct tcb_s *parent;
  FAR struct tcb_s *child;
  FAR char **argv;
  size_t stack_size;
  uint8_t ttype;
  int priority;
  int ret;

  DEBUGASSERT(retaddr != NULL);

  /* Get the type of the fork'ed task (kernel or user) */

  if ((ptcb->flags & TCB_FLAG_TTYPE_MASK) == TCB_FLAG_TTYPE_KERNEL)
    {
      /* Fork'ed from a kernel thread */

      ttype = TCB_FLAG_TTYPE_KERNEL;
      parent = ptcb;
    }
  else
    {
      /* Fork'ed from a user task or pthread */

      ttype = TCB_FLAG_TTYPE_TASK;
      if ((ptcb->flags & TCB_FLAG_TTYPE_MASK) == TCB_FLAG_TTYPE_TASK)
        {
          parent = ptcb;
        }
      else
        {
          parent = nxsched_get_tcb(ptcb->group->tg_pid);
          if (parent == NULL)
            {
              ret = -ENOENT;
              goto errout;
            }
        }
    }

  /* Allocate a TCB for the child task. */

  child = kmm_zalloc(sizeof(struct tcb_s));
  if (!child)
    {
      serr("ERROR: Failed to allocate TCB\n");
      ret = -ENOMEM;
      goto errout;
    }

  child->flags |= TCB_FLAG_FREE_TCB;

  /* Initialize the task join */

  nxtask_joininit(child);