minix/kernel/system/do_exit.c
Philip Homburg c1da6e6e24 Allow a process to kill itself. Remove the endpoint of a process that kills
itself before reporting the singal to pm.
2006-03-15 12:01:59 +00:00

93 lines
3.1 KiB
C

/* The kernel call implemented in this file:
* m_type: SYS_EXIT
*
* The parameters for this kernel call are:
* m1_i1: PR_ENDPT (slot number of exiting process)
*/
#include "../system.h"
#include <minix/endpoint.h>
#if USE_EXIT
FORWARD _PROTOTYPE( void clear_proc, (register struct proc *rc));
/*===========================================================================*
* do_exit *
*===========================================================================*/
PUBLIC int do_exit(m_ptr)
message *m_ptr; /* pointer to request message */
{
/* Handle sys_exit. A user process has exited or a system process requests
* to exit. Only the PM can request other process slots to be cleared.
* The routine to clean up a process table slot cancels outstanding timers,
* possibly removes the process from the message queues, and resets certain
* process table fields to the default values.
*/
int exit_e;
/* Determine what process exited. User processes are handled here. */
if (PM_PROC_NR == who_p) {
if (m_ptr->PR_ENDPT != SELF) { /* PM tries to exit self */
if(!isokendpt(m_ptr->PR_ENDPT, &exit_e)) /* get exiting process */
return EINVAL;
clear_proc(proc_addr(exit_e)); /* exit a user process */
return(OK); /* report back to PM */
}
}
/* The PM or some other system process requested to be exited. */
clear_proc(proc_addr(who_p));
return(EDONTREPLY);
}
/*===========================================================================*
* clear_proc *
*===========================================================================*/
PRIVATE void clear_proc(rc)
register struct proc *rc; /* slot of process to clean up */
{
register struct proc *rp; /* iterate over process table */
register struct proc **xpp; /* iterate over caller queue */
int i;
int sys_id;
char saved_rts_flags;
/* Don't clear if already cleared. */
if(isemptyp(rc)) return;
/* Remove the process' ability to send and receive messages */
clear_endpoint(rc);
/* Turn off any alarm timers at the clock. */
reset_timer(&priv(rc)->s_alarm_timer);
/* Make sure that the exiting process is no longer scheduled. */
if (rc->p_rts_flags == 0) lock_dequeue(rc);
/* Check the table with IRQ hooks to see if hooks should be released. */
for (i=0; i < NR_IRQ_HOOKS; i++) {
int proc;
if (rc->p_endpoint == irq_hooks[i].proc_nr_e) {
rm_irq_handler(&irq_hooks[i]); /* remove interrupt handler */
irq_hooks[i].proc_nr_e = NONE; /* mark hook as free */
}
}
/* Release the process table slot. If this is a system process, also
* release its privilege structure. Further cleanup is not needed at
* this point. All important fields are reinitialized when the
* slots are assigned to another, new process.
*/
saved_rts_flags = rc->p_rts_flags;
rc->p_rts_flags = SLOT_FREE;
if (priv(rc)->s_flags & SYS_PROC) priv(rc)->s_proc_nr = NONE;
/* Clean up virtual memory */
if (rc->p_misc_flags & MF_VM)
vm_map_default(rc);
}
#endif /* USE_EXIT */