Re: [BProc] BProc & /dev/tty - anything to watch out?

[<ha...@no...>]

> It seemes that setsid() does not set 'leader' flag for masq-ed
> processes. This probably may be fixed in bproc-3.1.10/kernel/masq.c:
> 
>   int masq_setsid(void) {
>     ...
>     current->bproc.masq->session
> 	  = current->bproc.masq->pgrp
> 	  = current->bproc.masq->pid;
>     current->leader = 1;             /* this line added by Vaclav Hanzl */
>     return current->bproc.masq->pgrp;

This fix is not enough, also the condition testing setsid() result
from ghost is probably wrong. Seemes it should be:

int masq_setsid(void) {
    ...
    result = req->req.result;
    bproc_put_req(req);

    /*if (result == 0) {  VH: wrong test - result is session id or -1 */
    if (result > 0) {
	/* Ok, setsid succeeded for the ghost.  Now we have to do the same
	 * thing to ourselves on this side */
	current->bproc.masq->session
	    = current->bproc.masq->pgrp
	    = current->bproc.masq->pid;

	current->leader = 1; /* this line added by Vaclav Hanzl */
        
        /* VH: now result == current->bproc.masq->pid */

	return current->bproc.masq->pgrp;
    } else {
    ...


But it probably still is not enough. Now sshd seemes happy but bash
started on slave node goes to busy loop:

 --- SIGTTIN (Stopped (tty input)) ---
 rt_sigaction(SIGTTIN, {SIG_IGN}, {SIG_DFL}, 8) = 0
 ioctl(255, 0x540f, [0])                 = 0
 rt_sigaction(SIGTTIN, {SIG_DFL}, {SIG_IGN}, 8) = 0
 kill(0, SIGTTIN)                        = 0
 --- SIGTTIN (Stopped (tty input)) ---
 rt_sigaction(SIGTTIN, {SIG_IGN}, {SIG_DFL}, 8) = 0
 ioctl(255, 0x540f, [0])                 = 0
 rt_sigaction(SIGTTIN, {SIG_DFL}, {SIG_IGN}, 8) = 0
 kill(0, SIGTTIN)                        = 0

Yes, I probably stepped out to empty spaces yet to be filled by
bproc-ing ttys. Anybody cares about this or not?

Best Regards

Vaclav