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      1 /*	$OpenBSD: jobs.c,v 1.43 2015/09/10 22:48:58 nicm Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011,
      5  *		 2012, 2013, 2014, 2015, 2016, 2018
      6  *	mirabilos <m (at) mirbsd.org>
      7  *
      8  * Provided that these terms and disclaimer and all copyright notices
      9  * are retained or reproduced in an accompanying document, permission
     10  * is granted to deal in this work without restriction, including un-
     11  * limited rights to use, publicly perform, distribute, sell, modify,
     12  * merge, give away, or sublicence.
     13  *
     14  * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
     15  * the utmost extent permitted by applicable law, neither express nor
     16  * implied; without malicious intent or gross negligence. In no event
     17  * may a licensor, author or contributor be held liable for indirect,
     18  * direct, other damage, loss, or other issues arising in any way out
     19  * of dealing in the work, even if advised of the possibility of such
     20  * damage or existence of a defect, except proven that it results out
     21  * of said person's immediate fault when using the work as intended.
     22  */
     23 
     24 #include "sh.h"
     25 
     26 __RCSID("$MirOS: src/bin/mksh/jobs.c,v 1.127 2018/07/15 16:23:10 tg Exp $");
     27 
     28 #if HAVE_KILLPG
     29 #define mksh_killpg		killpg
     30 #else
     31 /* cross fingers and hope kill is killpg-endowed */
     32 #define mksh_killpg(p,s)	kill(-(p), (s))
     33 #endif
     34 
     35 /* Order important! */
     36 #define PRUNNING	0
     37 #define PEXITED		1
     38 #define PSIGNALLED	2
     39 #define PSTOPPED	3
     40 
     41 typedef struct proc Proc;
     42 /* to take alignment into consideration */
     43 struct proc_dummy {
     44 	Proc *next;
     45 	pid_t pid;
     46 	int state;
     47 	int status;
     48 	char command[128];
     49 };
     50 /* real structure */
     51 struct proc {
     52 	/* next process in pipeline (if any) */
     53 	Proc *next;
     54 	/* process id of this Unix process in the job */
     55 	pid_t pid;
     56 	/* one of the four P above */
     57 	int state;
     58 	/* wait status */
     59 	int status;
     60 	/* process command string from vistree */
     61 	char command[256 - (ALLOC_OVERHEAD +
     62 	    offsetof(struct proc_dummy, command[0]))];
     63 };
     64 
     65 /* Notify/print flag - j_print() argument */
     66 #define JP_SHORT	1	/* print signals processes were killed by */
     67 #define JP_MEDIUM	2	/* print [job-num] -/+ command */
     68 #define JP_LONG		3	/* print [job-num] -/+ pid command */
     69 #define JP_PGRP		4	/* print pgrp */
     70 
     71 /* put_job() flags */
     72 #define PJ_ON_FRONT	0	/* at very front */
     73 #define PJ_PAST_STOPPED	1	/* just past any stopped jobs */
     74 
     75 /* Job.flags values */
     76 #define JF_STARTED	0x001	/* set when all processes in job are started */
     77 #define JF_WAITING	0x002	/* set if j_waitj() is waiting on job */
     78 #define JF_W_ASYNCNOTIFY 0x004	/* set if waiting and async notification ok */
     79 #define JF_XXCOM	0x008	/* set for $(command) jobs */
     80 #define JF_FG		0x010	/* running in foreground (also has tty pgrp) */
     81 #define JF_SAVEDTTY	0x020	/* j->ttystat is valid */
     82 #define JF_CHANGED	0x040	/* process has changed state */
     83 #define JF_KNOWN	0x080	/* $! referenced */
     84 #define JF_ZOMBIE	0x100	/* known, unwaited process */
     85 #define JF_REMOVE	0x200	/* flagged for removal (j_jobs()/j_noityf()) */
     86 #define JF_USETTYMODE	0x400	/* tty mode saved if process exits normally */
     87 #define JF_SAVEDTTYPGRP	0x800	/* j->saved_ttypgrp is valid */
     88 
     89 typedef struct job Job;
     90 struct job {
     91 	Job *next;		/* next job in list */
     92 	Proc *proc_list;	/* process list */
     93 	Proc *last_proc;	/* last process in list */
     94 	struct timeval systime;	/* system time used by job */
     95 	struct timeval usrtime;	/* user time used by job */
     96 	pid_t pgrp;		/* process group of job */
     97 	pid_t ppid;		/* pid of process that forked job */
     98 	int job;		/* job number: %n */
     99 	int flags;		/* see JF_* */
    100 	volatile int state;	/* job state */
    101 	int status;		/* exit status of last process */
    102 	int age;		/* number of jobs started */
    103 	Coproc_id coproc_id;	/* 0 or id of coprocess output pipe */
    104 #ifndef MKSH_UNEMPLOYED
    105 	mksh_ttyst ttystat;	/* saved tty state for stopped jobs */
    106 	pid_t saved_ttypgrp;	/* saved tty process group for stopped jobs */
    107 #endif
    108 };
    109 
    110 /* Flags for j_waitj() */
    111 #define JW_NONE		0x00
    112 #define JW_INTERRUPT	0x01	/* ^C will stop the wait */
    113 #define JW_ASYNCNOTIFY	0x02	/* asynchronous notification during wait ok */
    114 #define JW_STOPPEDWAIT	0x04	/* wait even if job stopped */
    115 #define JW_PIPEST	0x08	/* want PIPESTATUS */
    116 
    117 /* Error codes for j_lookup() */
    118 #define JL_NOSUCH	0	/* no such job */
    119 #define JL_AMBIG	1	/* %foo or %?foo is ambiguous */
    120 #define JL_INVALID	2	/* non-pid, non-% job id */
    121 
    122 static const char * const lookup_msgs[] = {
    123 	"no such job",
    124 	"ambiguous",
    125 	"argument must be %job or process id"
    126 };
    127 
    128 static Job *job_list;		/* job list */
    129 static Job *last_job;
    130 static Job *async_job;
    131 static pid_t async_pid;
    132 
    133 static int nzombie;		/* # of zombies owned by this process */
    134 static int njobs;		/* # of jobs started */
    135 
    136 #ifndef CHILD_MAX
    137 #define CHILD_MAX	25
    138 #endif
    139 
    140 #ifndef MKSH_NOPROSPECTOFWORK
    141 /* held_sigchld is set if sigchld occurs before a job is completely started */
    142 static volatile sig_atomic_t held_sigchld;
    143 #endif
    144 
    145 #ifndef MKSH_UNEMPLOYED
    146 static struct shf	*shl_j;
    147 static bool		ttypgrp_ok;	/* set if can use tty pgrps */
    148 static pid_t		restore_ttypgrp = -1;
    149 static int const	tt_sigs[] = { SIGTSTP, SIGTTIN, SIGTTOU };
    150 #endif
    151 
    152 static void		j_set_async(Job *);
    153 static void		j_startjob(Job *);
    154 static int		j_waitj(Job *, int, const char *);
    155 static void		j_sigchld(int);
    156 static void		j_print(Job *, int, struct shf *);
    157 static Job		*j_lookup(const char *, int *);
    158 static Job		*new_job(void);
    159 static Proc		*new_proc(void);
    160 static void		check_job(Job *);
    161 static void		put_job(Job *, int);
    162 static void		remove_job(Job *, const char *);
    163 static int		kill_job(Job *, int);
    164 
    165 static void tty_init_talking(void);
    166 static void tty_init_state(void);
    167 
    168 /* initialise job control */
    169 void
    170 j_init(void)
    171 {
    172 #ifndef MKSH_NOPROSPECTOFWORK
    173 	(void)sigemptyset(&sm_default);
    174 	sigprocmask(SIG_SETMASK, &sm_default, NULL);
    175 
    176 	(void)sigemptyset(&sm_sigchld);
    177 	(void)sigaddset(&sm_sigchld, SIGCHLD);
    178 
    179 	setsig(&sigtraps[SIGCHLD], j_sigchld,
    180 	    SS_RESTORE_ORIG|SS_FORCE|SS_SHTRAP);
    181 #else
    182 	/* Make sure SIGCHLD isn't ignored - can do odd things under SYSV */
    183 	setsig(&sigtraps[SIGCHLD], SIG_DFL, SS_RESTORE_ORIG|SS_FORCE);
    184 #endif
    185 
    186 #ifndef MKSH_UNEMPLOYED
    187 	if (Flag(FMONITOR) == 127)
    188 		Flag(FMONITOR) = Flag(FTALKING);
    189 
    190 	/*
    191 	 * shl_j is used to do asynchronous notification (used in
    192 	 * an interrupt handler, so need a distinct shf)
    193 	 */
    194 	shl_j = shf_fdopen(2, SHF_WR, NULL);
    195 
    196 	if (Flag(FMONITOR) || Flag(FTALKING)) {
    197 		int i;
    198 
    199 		/*
    200 		 * the TF_SHELL_USES test is a kludge that lets us know if
    201 		 * if the signals have been changed by the shell.
    202 		 */
    203 		for (i = NELEM(tt_sigs); --i >= 0; ) {
    204 			sigtraps[tt_sigs[i]].flags |= TF_SHELL_USES;
    205 			/* j_change() sets this to SS_RESTORE_DFL if FMONITOR */
    206 			setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
    207 			    SS_RESTORE_IGN|SS_FORCE);
    208 		}
    209 	}
    210 
    211 	/* j_change() calls tty_init_talking() and tty_init_state() */
    212 	if (Flag(FMONITOR))
    213 		j_change();
    214 	else
    215 #endif
    216 	  if (Flag(FTALKING)) {
    217 		tty_init_talking();
    218 		tty_init_state();
    219 	}
    220 }
    221 
    222 static int
    223 proc_errorlevel(Proc *p)
    224 {
    225 	switch (p->state) {
    226 	case PEXITED:
    227 		return ((WEXITSTATUS(p->status)) & 255);
    228 	case PSIGNALLED:
    229 		return (ksh_sigmask(WTERMSIG(p->status)));
    230 	default:
    231 		return (0);
    232 	}
    233 }
    234 
    235 #if !defined(MKSH_UNEMPLOYED) && HAVE_GETSID
    236 /* suspend the shell */
    237 void
    238 j_suspend(void)
    239 {
    240 	struct sigaction sa, osa;
    241 
    242 	/* Restore tty and pgrp. */
    243 	if (ttypgrp_ok) {
    244 		if (tty_hasstate)
    245 			mksh_tcset(tty_fd, &tty_state);
    246 		if (restore_ttypgrp >= 0) {
    247 			if (tcsetpgrp(tty_fd, restore_ttypgrp) < 0) {
    248 				warningf(false, Tf_ssfaileds,
    249 				    Tj_suspend, "tcsetpgrp", cstrerror(errno));
    250 			} else if (setpgid(0, restore_ttypgrp) < 0) {
    251 				warningf(false, Tf_ssfaileds,
    252 				    Tj_suspend, "setpgid", cstrerror(errno));
    253 			}
    254 		}
    255 	}
    256 
    257 	/* Suspend the shell. */
    258 	memset(&sa, 0, sizeof(sa));
    259 	sigemptyset(&sa.sa_mask);
    260 	sa.sa_handler = SIG_DFL;
    261 	sigaction(SIGTSTP, &sa, &osa);
    262 	kill(0, SIGTSTP);
    263 
    264 	/* Back from suspend, reset signals, pgrp and tty. */
    265 	sigaction(SIGTSTP, &osa, NULL);
    266 	if (ttypgrp_ok) {
    267 		if (restore_ttypgrp >= 0) {
    268 			if (setpgid(0, kshpid) < 0) {
    269 				warningf(false, Tf_ssfaileds,
    270 				    Tj_suspend, "setpgid", cstrerror(errno));
    271 				ttypgrp_ok = false;
    272 			} else if (tcsetpgrp(tty_fd, kshpid) < 0) {
    273 				warningf(false, Tf_ssfaileds,
    274 				    Tj_suspend, "tcsetpgrp", cstrerror(errno));
    275 				ttypgrp_ok = false;
    276 			}
    277 		}
    278 		tty_init_state();
    279 	}
    280 }
    281 #endif
    282 
    283 /* job cleanup before shell exit */
    284 void
    285 j_exit(void)
    286 {
    287 	/* kill stopped, and possibly running, jobs */
    288 	Job *j;
    289 	bool killed = false;
    290 
    291 	for (j = job_list; j != NULL; j = j->next) {
    292 		if (j->ppid == procpid &&
    293 		    (j->state == PSTOPPED ||
    294 		    (j->state == PRUNNING &&
    295 		    ((j->flags & JF_FG) ||
    296 		    (Flag(FLOGIN) && !Flag(FNOHUP) && procpid == kshpid))))) {
    297 			killed = true;
    298 			if (j->pgrp == 0)
    299 				kill_job(j, SIGHUP);
    300 			else
    301 				mksh_killpg(j->pgrp, SIGHUP);
    302 #ifndef MKSH_UNEMPLOYED
    303 			if (j->state == PSTOPPED) {
    304 				if (j->pgrp == 0)
    305 					kill_job(j, SIGCONT);
    306 				else
    307 					mksh_killpg(j->pgrp, SIGCONT);
    308 			}
    309 #endif
    310 		}
    311 	}
    312 	if (killed)
    313 		sleep(1);
    314 	j_notify();
    315 
    316 #ifndef MKSH_UNEMPLOYED
    317 	if (kshpid == procpid && restore_ttypgrp >= 0) {
    318 		/*
    319 		 * Need to restore the tty pgrp to what it was when the
    320 		 * shell started up, so that the process that started us
    321 		 * will be able to access the tty when we are done.
    322 		 * Also need to restore our process group in case we are
    323 		 * about to do an exec so that both our parent and the
    324 		 * process we are to become will be able to access the tty.
    325 		 */
    326 		tcsetpgrp(tty_fd, restore_ttypgrp);
    327 		setpgid(0, restore_ttypgrp);
    328 	}
    329 	if (Flag(FMONITOR)) {
    330 		Flag(FMONITOR) = 0;
    331 		j_change();
    332 	}
    333 #endif
    334 }
    335 
    336 #ifndef MKSH_UNEMPLOYED
    337 /* turn job control on or off according to Flag(FMONITOR) */
    338 void
    339 j_change(void)
    340 {
    341 	int i;
    342 
    343 	if (Flag(FMONITOR)) {
    344 		bool use_tty = Flag(FTALKING);
    345 
    346 		/* don't call mksh_tcget until we own the tty process group */
    347 		if (use_tty)
    348 			tty_init_talking();
    349 
    350 		/* no controlling tty, no SIGT* */
    351 		if ((ttypgrp_ok = (use_tty && tty_fd >= 0 && tty_devtty))) {
    352 			setsig(&sigtraps[SIGTTIN], SIG_DFL,
    353 			    SS_RESTORE_ORIG|SS_FORCE);
    354 			/* wait to be given tty (POSIX.1, B.2, job control) */
    355 			while (/* CONSTCOND */ 1) {
    356 				pid_t ttypgrp;
    357 
    358 				if ((ttypgrp = tcgetpgrp(tty_fd)) < 0) {
    359 					warningf(false, Tf_ssfaileds,
    360 					    "j_init", "tcgetpgrp",
    361 					    cstrerror(errno));
    362 					ttypgrp_ok = false;
    363 					break;
    364 				}
    365 				if (ttypgrp == kshpgrp)
    366 					break;
    367 				kill(0, SIGTTIN);
    368 			}
    369 		}
    370 		for (i = NELEM(tt_sigs); --i >= 0; )
    371 			setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
    372 			    SS_RESTORE_DFL|SS_FORCE);
    373 		if (ttypgrp_ok && kshpgrp != kshpid) {
    374 			if (setpgid(0, kshpid) < 0) {
    375 				warningf(false, Tf_ssfaileds,
    376 				    "j_init", "setpgid", cstrerror(errno));
    377 				ttypgrp_ok = false;
    378 			} else {
    379 				if (tcsetpgrp(tty_fd, kshpid) < 0) {
    380 					warningf(false, Tf_ssfaileds,
    381 					    "j_init", "tcsetpgrp",
    382 					    cstrerror(errno));
    383 					ttypgrp_ok = false;
    384 				} else
    385 					restore_ttypgrp = kshpgrp;
    386 				kshpgrp = kshpid;
    387 			}
    388 		}
    389 #ifndef MKSH_DISABLE_TTY_WARNING
    390 		if (use_tty && !ttypgrp_ok)
    391 			warningf(false, Tf_sD_s, "warning",
    392 			    "won't have full job control");
    393 #endif
    394 	} else {
    395 		ttypgrp_ok = false;
    396 		if (Flag(FTALKING))
    397 			for (i = NELEM(tt_sigs); --i >= 0; )
    398 				setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
    399 				    SS_RESTORE_IGN|SS_FORCE);
    400 		else
    401 			for (i = NELEM(tt_sigs); --i >= 0; ) {
    402 				if (sigtraps[tt_sigs[i]].flags &
    403 				    (TF_ORIG_IGN | TF_ORIG_DFL))
    404 					setsig(&sigtraps[tt_sigs[i]],
    405 					    (sigtraps[tt_sigs[i]].flags & TF_ORIG_IGN) ?
    406 					    SIG_IGN : SIG_DFL,
    407 					    SS_RESTORE_ORIG|SS_FORCE);
    408 			}
    409 	}
    410 	tty_init_state();
    411 }
    412 #endif
    413 
    414 #if HAVE_NICE
    415 /* run nice(3) and ignore the result */
    416 static void
    417 ksh_nice(int ness)
    418 {
    419 #if defined(__USE_FORTIFY_LEVEL) && (__USE_FORTIFY_LEVEL > 0)
    420 	int eno;
    421 
    422 	errno = 0;
    423 	/* this is gonna annoy users; complain to your distro, people! */
    424 	if (nice(ness) == -1 && (eno = errno) != 0)
    425 		warningf(false, Tf_sD_s, "bgnice", cstrerror(eno));
    426 #else
    427 	(void)nice(ness);
    428 #endif
    429 }
    430 #endif
    431 
    432 /* execute tree in child subprocess */
    433 int
    434 exchild(struct op *t, int flags,
    435     volatile int *xerrok,
    436     /* used if XPCLOSE or XCCLOSE */
    437     int close_fd)
    438 {
    439 	/* for pipelines */
    440 	static Proc *last_proc;
    441 
    442 	int rv = 0, forksleep, jwflags = JW_NONE;
    443 #ifndef MKSH_NOPROSPECTOFWORK
    444 	sigset_t omask;
    445 #endif
    446 	Proc *p;
    447 	Job *j;
    448 	pid_t cldpid;
    449 
    450 	if (flags & XPIPEST) {
    451 		flags &= ~XPIPEST;
    452 		jwflags |= JW_PIPEST;
    453 	}
    454 
    455 	if (flags & XEXEC)
    456 		/*
    457 		 * Clear XFORK|XPCLOSE|XCCLOSE|XCOPROC|XPIPEO|XPIPEI|XXCOM|XBGND
    458 		 * (also done in another execute() below)
    459 		 */
    460 		return (execute(t, flags & (XEXEC | XERROK), xerrok));
    461 
    462 #ifndef MKSH_NOPROSPECTOFWORK
    463 	/* no SIGCHLDs while messing with job and process lists */
    464 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
    465 #endif
    466 
    467 	p = new_proc();
    468 	p->next = NULL;
    469 	p->state = PRUNNING;
    470 	p->status = 0;
    471 	p->pid = 0;
    472 
    473 	/* link process into jobs list */
    474 	if (flags & XPIPEI) {
    475 		/* continuing with a pipe */
    476 		if (!last_job)
    477 			internal_errorf("exchild: XPIPEI and no last_job - pid %d",
    478 			    (int)procpid);
    479 		j = last_job;
    480 		if (last_proc)
    481 			last_proc->next = p;
    482 		last_proc = p;
    483 	} else {
    484 		/* fills in j->job */
    485 		j = new_job();
    486 		/*
    487 		 * we don't consider XXCOMs foreground since they don't get
    488 		 * tty process group and we don't save or restore tty modes.
    489 		 */
    490 		j->flags = (flags & XXCOM) ? JF_XXCOM :
    491 		    ((flags & XBGND) ? 0 : (JF_FG|JF_USETTYMODE));
    492 		timerclear(&j->usrtime);
    493 		timerclear(&j->systime);
    494 		j->state = PRUNNING;
    495 		j->pgrp = 0;
    496 		j->ppid = procpid;
    497 		j->age = ++njobs;
    498 		j->proc_list = p;
    499 		j->coproc_id = 0;
    500 		last_job = j;
    501 		last_proc = p;
    502 		put_job(j, PJ_PAST_STOPPED);
    503 	}
    504 
    505 	vistree(p->command, sizeof(p->command), t);
    506 
    507 	/* create child process */
    508 	forksleep = 1;
    509 	while ((cldpid = fork()) < 0 && errno == EAGAIN && forksleep < 32) {
    510 		if (intrsig)
    511 			/* allow user to ^C out... */
    512 			break;
    513 		sleep(forksleep);
    514 		forksleep <<= 1;
    515 	}
    516 	/* ensure $RANDOM changes between parent and child */
    517 	rndset((unsigned long)cldpid);
    518 	/* fork failed? */
    519 	if (cldpid < 0) {
    520 		kill_job(j, SIGKILL);
    521 		remove_job(j, "fork failed");
    522 #ifndef MKSH_NOPROSPECTOFWORK
    523 		sigprocmask(SIG_SETMASK, &omask, NULL);
    524 #endif
    525 		errorf("can't fork - try again");
    526 	}
    527 	p->pid = cldpid ? cldpid : (procpid = getpid());
    528 
    529 #ifndef MKSH_UNEMPLOYED
    530 	/* job control set up */
    531 	if (Flag(FMONITOR) && !(flags&XXCOM)) {
    532 		bool dotty = false;
    533 
    534 		if (j->pgrp == 0) {
    535 			/* First process */
    536 			j->pgrp = p->pid;
    537 			dotty = true;
    538 		}
    539 
    540 		/*
    541 		 * set pgrp in both parent and child to deal with race
    542 		 * condition
    543 		 */
    544 		setpgid(p->pid, j->pgrp);
    545 		if (ttypgrp_ok && dotty && !(flags & XBGND))
    546 			tcsetpgrp(tty_fd, j->pgrp);
    547 	}
    548 #endif
    549 
    550 	/* used to close pipe input fd */
    551 	if (close_fd >= 0 && (((flags & XPCLOSE) && cldpid) ||
    552 	    ((flags & XCCLOSE) && !cldpid)))
    553 		close(close_fd);
    554 	if (!cldpid) {
    555 		/* child */
    556 
    557 		/* Do this before restoring signal */
    558 		if (flags & XCOPROC)
    559 			coproc_cleanup(false);
    560 		cleanup_parents_env();
    561 #ifndef MKSH_UNEMPLOYED
    562 		/*
    563 		 * If FMONITOR or FTALKING is set, these signals are ignored,
    564 		 * if neither FMONITOR nor FTALKING are set, the signals have
    565 		 * their inherited values.
    566 		 */
    567 		if (Flag(FMONITOR) && !(flags & XXCOM)) {
    568 			for (forksleep = NELEM(tt_sigs); --forksleep >= 0; )
    569 				setsig(&sigtraps[tt_sigs[forksleep]], SIG_DFL,
    570 				    SS_RESTORE_DFL|SS_FORCE);
    571 		}
    572 #endif
    573 #if HAVE_NICE
    574 		if (Flag(FBGNICE) && (flags & XBGND))
    575 			ksh_nice(4);
    576 #endif
    577 		if ((flags & XBGND)
    578 #ifndef MKSH_UNEMPLOYED
    579 		    && !Flag(FMONITOR)
    580 #endif
    581 		    ) {
    582 			setsig(&sigtraps[SIGINT], SIG_IGN,
    583 			    SS_RESTORE_IGN|SS_FORCE);
    584 			setsig(&sigtraps[SIGQUIT], SIG_IGN,
    585 			    SS_RESTORE_IGN|SS_FORCE);
    586 			if ((!(flags & (XPIPEI | XCOPROC))) &&
    587 			    ((forksleep = open("/dev/null", 0)) > 0)) {
    588 				(void)ksh_dup2(forksleep, 0, true);
    589 				close(forksleep);
    590 			}
    591 		}
    592 		/* in case of $(jobs) command */
    593 		remove_job(j, "child");
    594 #ifndef MKSH_NOPROSPECTOFWORK
    595 		/* remove_job needs SIGCHLD blocked still */
    596 		sigprocmask(SIG_SETMASK, &omask, NULL);
    597 #endif
    598 		nzombie = 0;
    599 #ifndef MKSH_UNEMPLOYED
    600 		ttypgrp_ok = false;
    601 		Flag(FMONITOR) = 0;
    602 #endif
    603 		Flag(FTALKING) = 0;
    604 		cleartraps();
    605 		/* no return */
    606 		execute(t, (flags & XERROK) | XEXEC, NULL);
    607 #ifndef MKSH_SMALL
    608 		if (t->type == TPIPE)
    609 			unwind(LLEAVE);
    610 		internal_warningf("%s: execute() returned", "exchild");
    611 		fptreef(shl_out, 8, "%s: tried to execute {\n\t%T\n}\n",
    612 		    "exchild", t);
    613 		shf_flush(shl_out);
    614 #endif
    615 		unwind(LLEAVE);
    616 		/* NOTREACHED */
    617 	}
    618 
    619 	/* shell (parent) stuff */
    620 	if (!(flags & XPIPEO)) {
    621 		/* last process in a job */
    622 		j_startjob(j);
    623 		if (flags & XCOPROC) {
    624 			j->coproc_id = coproc.id;
    625 			/* n jobs using co-process output */
    626 			coproc.njobs++;
    627 			/* j using co-process input */
    628 			coproc.job = (void *)j;
    629 		}
    630 		if (flags & XBGND) {
    631 			j_set_async(j);
    632 			if (Flag(FTALKING)) {
    633 				shf_fprintf(shl_out, "[%d]", j->job);
    634 				for (p = j->proc_list; p; p = p->next)
    635 					shf_fprintf(shl_out, Tf__d,
    636 					    (int)p->pid);
    637 				shf_putchar('\n', shl_out);
    638 				shf_flush(shl_out);
    639 			}
    640 		} else
    641 			rv = j_waitj(j, jwflags, "jw:last proc");
    642 	}
    643 
    644 #ifndef MKSH_NOPROSPECTOFWORK
    645 	sigprocmask(SIG_SETMASK, &omask, NULL);
    646 #endif
    647 
    648 	return (rv);
    649 }
    650 
    651 /* start the last job: only used for $(command) jobs */
    652 void
    653 startlast(void)
    654 {
    655 #ifndef MKSH_NOPROSPECTOFWORK
    656 	sigset_t omask;
    657 
    658 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
    659 #endif
    660 
    661 	/* no need to report error - waitlast() will do it */
    662 	if (last_job) {
    663 		/* ensure it isn't removed by check_job() */
    664 		last_job->flags |= JF_WAITING;
    665 		j_startjob(last_job);
    666 	}
    667 #ifndef MKSH_NOPROSPECTOFWORK
    668 	sigprocmask(SIG_SETMASK, &omask, NULL);
    669 #endif
    670 }
    671 
    672 /* wait for last job: only used for $(command) jobs */
    673 int
    674 waitlast(void)
    675 {
    676 	int rv;
    677 	Job *j;
    678 #ifndef MKSH_NOPROSPECTOFWORK
    679 	sigset_t omask;
    680 
    681 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
    682 #endif
    683 
    684 	j = last_job;
    685 	if (!j || !(j->flags & JF_STARTED)) {
    686 		if (!j)
    687 			warningf(true, Tf_sD_s, "waitlast", "no last job");
    688 		else
    689 			internal_warningf(Tf_sD_s, "waitlast", Tnot_started);
    690 #ifndef MKSH_NOPROSPECTOFWORK
    691 		sigprocmask(SIG_SETMASK, &omask, NULL);
    692 #endif
    693 		/* not so arbitrary, non-zero value */
    694 		return (125);
    695 	}
    696 
    697 	rv = j_waitj(j, JW_NONE, "waitlast");
    698 
    699 #ifndef MKSH_NOPROSPECTOFWORK
    700 	sigprocmask(SIG_SETMASK, &omask, NULL);
    701 #endif
    702 
    703 	return (rv);
    704 }
    705 
    706 /* wait for child, interruptable. */
    707 int
    708 waitfor(const char *cp, int *sigp)
    709 {
    710 	int rv, ecode, flags = JW_INTERRUPT|JW_ASYNCNOTIFY;
    711 	Job *j;
    712 #ifndef MKSH_NOPROSPECTOFWORK
    713 	sigset_t omask;
    714 
    715 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
    716 #endif
    717 
    718 	*sigp = 0;
    719 
    720 	if (cp == NULL) {
    721 		/*
    722 		 * wait for an unspecified job - always returns 0, so
    723 		 * don't have to worry about exited/signaled jobs
    724 		 */
    725 		for (j = job_list; j; j = j->next)
    726 			/* AT&T ksh will wait for stopped jobs - we don't */
    727 			if (j->ppid == procpid && j->state == PRUNNING)
    728 				break;
    729 		if (!j) {
    730 #ifndef MKSH_NOPROSPECTOFWORK
    731 			sigprocmask(SIG_SETMASK, &omask, NULL);
    732 #endif
    733 			return (-1);
    734 		}
    735 	} else if ((j = j_lookup(cp, &ecode))) {
    736 		/* don't report normal job completion */
    737 		flags &= ~JW_ASYNCNOTIFY;
    738 		if (j->ppid != procpid) {
    739 #ifndef MKSH_NOPROSPECTOFWORK
    740 			sigprocmask(SIG_SETMASK, &omask, NULL);
    741 #endif
    742 			return (-1);
    743 		}
    744 	} else {
    745 #ifndef MKSH_NOPROSPECTOFWORK
    746 		sigprocmask(SIG_SETMASK, &omask, NULL);
    747 #endif
    748 		if (ecode != JL_NOSUCH)
    749 			bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
    750 		return (-1);
    751 	}
    752 
    753 	/* AT&T ksh will wait for stopped jobs - we don't */
    754 	rv = j_waitj(j, flags, "jw:waitfor");
    755 
    756 #ifndef MKSH_NOPROSPECTOFWORK
    757 	sigprocmask(SIG_SETMASK, &omask, NULL);
    758 #endif
    759 
    760 	if (rv < 0)
    761 		/* we were interrupted */
    762 		*sigp = ksh_sigmask(-rv);
    763 
    764 	return (rv);
    765 }
    766 
    767 /* kill (built-in) a job */
    768 int
    769 j_kill(const char *cp, int sig)
    770 {
    771 	Job *j;
    772 	int rv = 0, ecode;
    773 #ifndef MKSH_NOPROSPECTOFWORK
    774 	sigset_t omask;
    775 
    776 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
    777 #endif
    778 
    779 	if ((j = j_lookup(cp, &ecode)) == NULL) {
    780 #ifndef MKSH_NOPROSPECTOFWORK
    781 		sigprocmask(SIG_SETMASK, &omask, NULL);
    782 #endif
    783 		bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
    784 		return (1);
    785 	}
    786 
    787 	if (j->pgrp == 0) {
    788 		/* started when !Flag(FMONITOR) */
    789 		if (kill_job(j, sig) < 0) {
    790 			bi_errorf(Tf_sD_s, cp, cstrerror(errno));
    791 			rv = 1;
    792 		}
    793 	} else {
    794 #ifndef MKSH_UNEMPLOYED
    795 		if (j->state == PSTOPPED && (sig == SIGTERM || sig == SIGHUP))
    796 			mksh_killpg(j->pgrp, SIGCONT);
    797 #endif
    798 		if (mksh_killpg(j->pgrp, sig) < 0) {
    799 			bi_errorf(Tf_sD_s, cp, cstrerror(errno));
    800 			rv = 1;
    801 		}
    802 	}
    803 
    804 #ifndef MKSH_NOPROSPECTOFWORK
    805 	sigprocmask(SIG_SETMASK, &omask, NULL);
    806 #endif
    807 
    808 	return (rv);
    809 }
    810 
    811 #ifndef MKSH_UNEMPLOYED
    812 /* fg and bg built-ins: called only if Flag(FMONITOR) set */
    813 int
    814 j_resume(const char *cp, int bg)
    815 {
    816 	Job *j;
    817 	Proc *p;
    818 	int ecode, rv = 0;
    819 	bool running;
    820 	sigset_t omask;
    821 
    822 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
    823 
    824 	if ((j = j_lookup(cp, &ecode)) == NULL) {
    825 		sigprocmask(SIG_SETMASK, &omask, NULL);
    826 		bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
    827 		return (1);
    828 	}
    829 
    830 	if (j->pgrp == 0) {
    831 		sigprocmask(SIG_SETMASK, &omask, NULL);
    832 		bi_errorf("job not job-controlled");
    833 		return (1);
    834 	}
    835 
    836 	if (bg)
    837 		shprintf("[%d] ", j->job);
    838 
    839 	running = false;
    840 	for (p = j->proc_list; p != NULL; p = p->next) {
    841 		if (p->state == PSTOPPED) {
    842 			p->state = PRUNNING;
    843 			p->status = 0;
    844 			running = true;
    845 		}
    846 		shf_puts(p->command, shl_stdout);
    847 		if (p->next)
    848 			shf_puts("| ", shl_stdout);
    849 	}
    850 	shf_putc('\n', shl_stdout);
    851 	shf_flush(shl_stdout);
    852 	if (running)
    853 		j->state = PRUNNING;
    854 
    855 	put_job(j, PJ_PAST_STOPPED);
    856 	if (bg)
    857 		j_set_async(j);
    858 	else {
    859 		/* attach tty to job */
    860 		if (j->state == PRUNNING) {
    861 			if (ttypgrp_ok && (j->flags & JF_SAVEDTTY))
    862 				mksh_tcset(tty_fd, &j->ttystat);
    863 			/* See comment in j_waitj regarding saved_ttypgrp. */
    864 			if (ttypgrp_ok &&
    865 			    tcsetpgrp(tty_fd, (j->flags & JF_SAVEDTTYPGRP) ?
    866 			    j->saved_ttypgrp : j->pgrp) < 0) {
    867 				rv = errno;
    868 				if (j->flags & JF_SAVEDTTY)
    869 					mksh_tcset(tty_fd, &tty_state);
    870 				sigprocmask(SIG_SETMASK, &omask, NULL);
    871 				bi_errorf(Tf_ldfailed,
    872 				    "fg: 1st", "tcsetpgrp", tty_fd,
    873 				    (long)((j->flags & JF_SAVEDTTYPGRP) ?
    874 				    j->saved_ttypgrp : j->pgrp),
    875 				    cstrerror(rv));
    876 				return (1);
    877 			}
    878 		}
    879 		j->flags |= JF_FG;
    880 		j->flags &= ~JF_KNOWN;
    881 		if (j == async_job)
    882 			async_job = NULL;
    883 	}
    884 
    885 	if (j->state == PRUNNING && mksh_killpg(j->pgrp, SIGCONT) < 0) {
    886 		int eno = errno;
    887 
    888 		if (!bg) {
    889 			j->flags &= ~JF_FG;
    890 			if (ttypgrp_ok && (j->flags & JF_SAVEDTTY))
    891 				mksh_tcset(tty_fd, &tty_state);
    892 			if (ttypgrp_ok && tcsetpgrp(tty_fd, kshpgrp) < 0)
    893 				warningf(true, Tf_ldfailed,
    894 				    "fg: 2nd", "tcsetpgrp", tty_fd,
    895 				    (long)kshpgrp, cstrerror(errno));
    896 		}
    897 		sigprocmask(SIG_SETMASK, &omask, NULL);
    898 		bi_errorf(Tf_s_sD_s, "can't continue job",
    899 		    cp, cstrerror(eno));
    900 		return (1);
    901 	}
    902 	if (!bg) {
    903 		if (ttypgrp_ok) {
    904 			j->flags &= ~(JF_SAVEDTTY | JF_SAVEDTTYPGRP);
    905 		}
    906 		rv = j_waitj(j, JW_NONE, "jw:resume");
    907 	}
    908 	sigprocmask(SIG_SETMASK, &omask, NULL);
    909 	return (rv);
    910 }
    911 #endif
    912 
    913 /* are there any running or stopped jobs ? */
    914 int
    915 j_stopped_running(void)
    916 {
    917 	Job *j;
    918 	int which = 0;
    919 
    920 	for (j = job_list; j != NULL; j = j->next) {
    921 #ifndef MKSH_UNEMPLOYED
    922 		if (j->ppid == procpid && j->state == PSTOPPED)
    923 			which |= 1;
    924 #endif
    925 		if (Flag(FLOGIN) && !Flag(FNOHUP) && procpid == kshpid &&
    926 		    j->ppid == procpid && j->state == PRUNNING)
    927 			which |= 2;
    928 	}
    929 	if (which) {
    930 		shellf("You have %s%s%s jobs\n",
    931 		    which & 1 ? "stopped" : "",
    932 		    which == 3 ? " and " : "",
    933 		    which & 2 ? "running" : "");
    934 		return (1);
    935 	}
    936 
    937 	return (0);
    938 }
    939 
    940 
    941 /* list jobs for jobs built-in */
    942 int
    943 j_jobs(const char *cp, int slp,
    944     /* 0: short, 1: long, 2: pgrp */
    945     int nflag)
    946 {
    947 	Job *j, *tmp;
    948 	int how, zflag = 0;
    949 #ifndef MKSH_NOPROSPECTOFWORK
    950 	sigset_t omask;
    951 
    952 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
    953 #endif
    954 
    955 	if (nflag < 0) {
    956 		/* kludge: print zombies */
    957 		nflag = 0;
    958 		zflag = 1;
    959 	}
    960 	if (cp) {
    961 		int ecode;
    962 
    963 		if ((j = j_lookup(cp, &ecode)) == NULL) {
    964 #ifndef MKSH_NOPROSPECTOFWORK
    965 			sigprocmask(SIG_SETMASK, &omask, NULL);
    966 #endif
    967 			bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
    968 			return (1);
    969 		}
    970 	} else
    971 		j = job_list;
    972 	how = slp == 0 ? JP_MEDIUM : (slp == 1 ? JP_LONG : JP_PGRP);
    973 	for (; j; j = j->next) {
    974 		if ((!(j->flags & JF_ZOMBIE) || zflag) &&
    975 		    (!nflag || (j->flags & JF_CHANGED))) {
    976 			j_print(j, how, shl_stdout);
    977 			if (j->state == PEXITED || j->state == PSIGNALLED)
    978 				j->flags |= JF_REMOVE;
    979 		}
    980 		if (cp)
    981 			break;
    982 	}
    983 	/* Remove jobs after printing so there won't be multiple + or - jobs */
    984 	for (j = job_list; j; j = tmp) {
    985 		tmp = j->next;
    986 		if (j->flags & JF_REMOVE)
    987 			remove_job(j, Tjobs);
    988 	}
    989 #ifndef MKSH_NOPROSPECTOFWORK
    990 	sigprocmask(SIG_SETMASK, &omask, NULL);
    991 #endif
    992 	return (0);
    993 }
    994 
    995 /* list jobs for top-level notification */
    996 void
    997 j_notify(void)
    998 {
    999 	Job *j, *tmp;
   1000 #ifndef MKSH_NOPROSPECTOFWORK
   1001 	sigset_t omask;
   1002 
   1003 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
   1004 #endif
   1005 	for (j = job_list; j; j = j->next) {
   1006 #ifndef MKSH_UNEMPLOYED
   1007 		if (Flag(FMONITOR) && (j->flags & JF_CHANGED))
   1008 			j_print(j, JP_MEDIUM, shl_out);
   1009 #endif
   1010 		/*
   1011 		 * Remove job after doing reports so there aren't
   1012 		 * multiple +/- jobs.
   1013 		 */
   1014 		if (j->state == PEXITED || j->state == PSIGNALLED)
   1015 			j->flags |= JF_REMOVE;
   1016 	}
   1017 	for (j = job_list; j; j = tmp) {
   1018 		tmp = j->next;
   1019 		if (j->flags & JF_REMOVE) {
   1020 			if (j == async_job || (j->flags & JF_KNOWN)) {
   1021 				j->flags = (j->flags & ~JF_REMOVE) | JF_ZOMBIE;
   1022 				j->job = -1;
   1023 				nzombie++;
   1024 			} else
   1025 				remove_job(j, "notify");
   1026 		}
   1027 	}
   1028 	shf_flush(shl_out);
   1029 #ifndef MKSH_NOPROSPECTOFWORK
   1030 	sigprocmask(SIG_SETMASK, &omask, NULL);
   1031 #endif
   1032 }
   1033 
   1034 /* Return pid of last process in last asynchronous job */
   1035 pid_t
   1036 j_async(void)
   1037 {
   1038 #ifndef MKSH_NOPROSPECTOFWORK
   1039 	sigset_t omask;
   1040 
   1041 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
   1042 #endif
   1043 
   1044 	if (async_job)
   1045 		async_job->flags |= JF_KNOWN;
   1046 
   1047 #ifndef MKSH_NOPROSPECTOFWORK
   1048 	sigprocmask(SIG_SETMASK, &omask, NULL);
   1049 #endif
   1050 
   1051 	return (async_pid);
   1052 }
   1053 
   1054 /*
   1055  * Make j the last async process
   1056  *
   1057  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1058  */
   1059 static void
   1060 j_set_async(Job *j)
   1061 {
   1062 	Job *jl, *oldest;
   1063 
   1064 	if (async_job && (async_job->flags & (JF_KNOWN|JF_ZOMBIE)) == JF_ZOMBIE)
   1065 		remove_job(async_job, "async");
   1066 	if (!(j->flags & JF_STARTED)) {
   1067 		internal_warningf(Tf_sD_s, "j_async", Tjob_not_started);
   1068 		return;
   1069 	}
   1070 	async_job = j;
   1071 	async_pid = j->last_proc->pid;
   1072 	while (nzombie > CHILD_MAX) {
   1073 		oldest = NULL;
   1074 		for (jl = job_list; jl; jl = jl->next)
   1075 			if (jl != async_job && (jl->flags & JF_ZOMBIE) &&
   1076 			    (!oldest || jl->age < oldest->age))
   1077 				oldest = jl;
   1078 		if (!oldest) {
   1079 			/* XXX debugging */
   1080 			if (!(async_job->flags & JF_ZOMBIE) || nzombie != 1) {
   1081 				internal_warningf("%s: bad nzombie (%d)",
   1082 				    "j_async", nzombie);
   1083 				nzombie = 0;
   1084 			}
   1085 			break;
   1086 		}
   1087 		remove_job(oldest, "zombie");
   1088 	}
   1089 }
   1090 
   1091 /*
   1092  * Start a job: set STARTED, check for held signals and set j->last_proc
   1093  *
   1094  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1095  */
   1096 static void
   1097 j_startjob(Job *j)
   1098 {
   1099 	Proc *p;
   1100 
   1101 	j->flags |= JF_STARTED;
   1102 	for (p = j->proc_list; p->next; p = p->next)
   1103 		;
   1104 	j->last_proc = p;
   1105 
   1106 #ifndef MKSH_NOPROSPECTOFWORK
   1107 	if (held_sigchld) {
   1108 		held_sigchld = 0;
   1109 		/* Don't call j_sigchld() as it may remove job... */
   1110 		kill(procpid, SIGCHLD);
   1111 	}
   1112 #endif
   1113 }
   1114 
   1115 /*
   1116  * wait for job to complete or change state
   1117  *
   1118  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1119  */
   1120 static int
   1121 j_waitj(Job *j,
   1122     /* see JW_* */
   1123     int flags,
   1124     const char *where)
   1125 {
   1126 	Proc *p;
   1127 	int rv;
   1128 #ifdef MKSH_NO_SIGSUSPEND
   1129 	sigset_t omask;
   1130 #endif
   1131 
   1132 	/*
   1133 	 * No auto-notify on the job we are waiting on.
   1134 	 */
   1135 	j->flags |= JF_WAITING;
   1136 	if (flags & JW_ASYNCNOTIFY)
   1137 		j->flags |= JF_W_ASYNCNOTIFY;
   1138 
   1139 #ifndef MKSH_UNEMPLOYED
   1140 	if (!Flag(FMONITOR))
   1141 #endif
   1142 		flags |= JW_STOPPEDWAIT;
   1143 
   1144 	while (j->state == PRUNNING ||
   1145 	    ((flags & JW_STOPPEDWAIT) && j->state == PSTOPPED)) {
   1146 #ifndef MKSH_NOPROSPECTOFWORK
   1147 #ifdef MKSH_NO_SIGSUSPEND
   1148 		sigprocmask(SIG_SETMASK, &sm_default, &omask);
   1149 		pause();
   1150 		/* note that handlers may run here so they need to know */
   1151 		sigprocmask(SIG_SETMASK, &omask, NULL);
   1152 #else
   1153 		sigsuspend(&sm_default);
   1154 #endif
   1155 #else
   1156 		j_sigchld(SIGCHLD);
   1157 #endif
   1158 		if (fatal_trap) {
   1159 			int oldf = j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY);
   1160 			j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
   1161 			runtraps(TF_FATAL);
   1162 			/* not reached... */
   1163 			j->flags |= oldf;
   1164 		}
   1165 		if ((flags & JW_INTERRUPT) && (rv = trap_pending())) {
   1166 			j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
   1167 			return (-rv);
   1168 		}
   1169 	}
   1170 	j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
   1171 
   1172 	if (j->flags & JF_FG) {
   1173 		j->flags &= ~JF_FG;
   1174 #ifndef MKSH_UNEMPLOYED
   1175 		if (Flag(FMONITOR) && ttypgrp_ok && j->pgrp) {
   1176 			/*
   1177 			 * Save the tty's current pgrp so it can be restored
   1178 			 * when the job is foregrounded. This is to
   1179 			 * deal with things like the GNU su which does
   1180 			 * a fork/exec instead of an exec (the fork means
   1181 			 * the execed shell gets a different pid from its
   1182 			 * pgrp, so naturally it sets its pgrp and gets hosed
   1183 			 * when it gets foregrounded by the parent shell which
   1184 			 * has restored the tty's pgrp to that of the su
   1185 			 * process).
   1186 			 */
   1187 			if (j->state == PSTOPPED &&
   1188 			    (j->saved_ttypgrp = tcgetpgrp(tty_fd)) >= 0)
   1189 				j->flags |= JF_SAVEDTTYPGRP;
   1190 			if (tcsetpgrp(tty_fd, kshpgrp) < 0)
   1191 				warningf(true, Tf_ldfailed,
   1192 				    "j_waitj:", "tcsetpgrp", tty_fd,
   1193 				    (long)kshpgrp, cstrerror(errno));
   1194 			if (j->state == PSTOPPED) {
   1195 				j->flags |= JF_SAVEDTTY;
   1196 				mksh_tcget(tty_fd, &j->ttystat);
   1197 			}
   1198 		}
   1199 #endif
   1200 		if (tty_hasstate) {
   1201 			/*
   1202 			 * Only restore tty settings if job was originally
   1203 			 * started in the foreground. Problems can be
   1204 			 * caused by things like 'more foobar &' which will
   1205 			 * typically get and save the shell's vi/emacs tty
   1206 			 * settings before setting up the tty for itself;
   1207 			 * when more exits, it restores the 'original'
   1208 			 * settings, and things go down hill from there...
   1209 			 */
   1210 			if (j->state == PEXITED && j->status == 0 &&
   1211 			    (j->flags & JF_USETTYMODE)) {
   1212 				mksh_tcget(tty_fd, &tty_state);
   1213 			} else {
   1214 				mksh_tcset(tty_fd, &tty_state);
   1215 				/*-
   1216 				 * Don't use tty mode if job is stopped and
   1217 				 * later restarted and exits. Consider
   1218 				 * the sequence:
   1219 				 *	vi foo (stopped)
   1220 				 *	...
   1221 				 *	stty something
   1222 				 *	...
   1223 				 *	fg (vi; ZZ)
   1224 				 * mode should be that of the stty, not what
   1225 				 * was before the vi started.
   1226 				 */
   1227 				if (j->state == PSTOPPED)
   1228 					j->flags &= ~JF_USETTYMODE;
   1229 			}
   1230 		}
   1231 #ifndef MKSH_UNEMPLOYED
   1232 		/*
   1233 		 * If it looks like user hit ^C to kill a job, pretend we got
   1234 		 * one too to break out of for loops, etc. (AT&T ksh does this
   1235 		 * even when not monitoring, but this doesn't make sense since
   1236 		 * a tty generated ^C goes to the whole process group)
   1237 		 */
   1238 		if (Flag(FMONITOR) && j->state == PSIGNALLED &&
   1239 		    WIFSIGNALED(j->last_proc->status)) {
   1240 			int termsig;
   1241 
   1242 			if ((termsig = WTERMSIG(j->last_proc->status)) > 0 &&
   1243 			    termsig < ksh_NSIG &&
   1244 			    (sigtraps[termsig].flags & TF_TTY_INTR))
   1245 				trapsig(termsig);
   1246 		}
   1247 #endif
   1248 	}
   1249 
   1250 	j_usrtime = j->usrtime;
   1251 	j_systime = j->systime;
   1252 	rv = j->status;
   1253 
   1254 	if (!(p = j->proc_list)) {
   1255 		;	/* nothing */
   1256 	} else if (flags & JW_PIPEST) {
   1257 		uint32_t num = 0;
   1258 		struct tbl *vp;
   1259 
   1260 		unset(vp_pipest, 1);
   1261 		vp = vp_pipest;
   1262 		vp->flag = DEFINED | ISSET | INTEGER | RDONLY | ARRAY | INT_U;
   1263 		goto got_array;
   1264 
   1265 		while (p != NULL) {
   1266 			{
   1267 				struct tbl *vq;
   1268 
   1269 				/* strlen(vp_pipest->name) == 10 */
   1270 				vq = alloc(offsetof(struct tbl, name[0]) + 11,
   1271 				    vp_pipest->areap);
   1272 				memset(vq, 0, offsetof(struct tbl, name[0]));
   1273 				memcpy(vq->name, vp_pipest->name, 11);
   1274 				vp->u.array = vq;
   1275 				vp = vq;
   1276 			}
   1277 			vp->areap = vp_pipest->areap;
   1278 			vp->ua.index = ++num;
   1279 			vp->flag = DEFINED | ISSET | INTEGER | RDONLY |
   1280 			    ARRAY | INT_U | AINDEX;
   1281  got_array:
   1282 			vp->val.i = proc_errorlevel(p);
   1283 			if (Flag(FPIPEFAIL) && vp->val.i)
   1284 				rv = vp->val.i;
   1285 			p = p->next;
   1286 		}
   1287 	} else if (Flag(FPIPEFAIL)) {
   1288 		do {
   1289 			const int i = proc_errorlevel(p);
   1290 
   1291 			if (i)
   1292 				rv = i;
   1293 		} while ((p = p->next));
   1294 	}
   1295 
   1296 	if (!(flags & JW_ASYNCNOTIFY)
   1297 #ifndef MKSH_UNEMPLOYED
   1298 	    && (!Flag(FMONITOR) || j->state != PSTOPPED)
   1299 #endif
   1300 	    ) {
   1301 		j_print(j, JP_SHORT, shl_out);
   1302 		shf_flush(shl_out);
   1303 	}
   1304 	if (j->state != PSTOPPED
   1305 #ifndef MKSH_UNEMPLOYED
   1306 	    && (!Flag(FMONITOR) || !(flags & JW_ASYNCNOTIFY))
   1307 #endif
   1308 	    )
   1309 		remove_job(j, where);
   1310 
   1311 	return (rv);
   1312 }
   1313 
   1314 /*
   1315  * SIGCHLD handler to reap children and update job states
   1316  *
   1317  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1318  */
   1319 /* ARGSUSED */
   1320 static void
   1321 j_sigchld(int sig MKSH_A_UNUSED)
   1322 {
   1323 	int saved_errno = errno;
   1324 	Job *j;
   1325 	Proc *p = NULL;
   1326 	pid_t pid;
   1327 	int status;
   1328 	struct rusage ru0, ru1;
   1329 #ifdef MKSH_NO_SIGSUSPEND
   1330 	sigset_t omask;
   1331 
   1332 	/* this handler can run while SIGCHLD is not blocked, so block it now */
   1333 	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
   1334 #endif
   1335 
   1336 #ifndef MKSH_NOPROSPECTOFWORK
   1337 	/*
   1338 	 * Don't wait for any processes if a job is partially started.
   1339 	 * This is so we don't do away with the process group leader
   1340 	 * before all the processes in a pipe line are started (so the
   1341 	 * setpgid() won't fail)
   1342 	 */
   1343 	for (j = job_list; j; j = j->next)
   1344 		if (j->ppid == procpid && !(j->flags & JF_STARTED)) {
   1345 			held_sigchld = 1;
   1346 			goto j_sigchld_out;
   1347 		}
   1348 #endif
   1349 
   1350 	getrusage(RUSAGE_CHILDREN, &ru0);
   1351 	do {
   1352 #ifndef MKSH_NOPROSPECTOFWORK
   1353 		pid = waitpid(-1, &status, (WNOHANG |
   1354 #if defined(WCONTINUED) && defined(WIFCONTINUED)
   1355 		    WCONTINUED |
   1356 #endif
   1357 		    WUNTRACED));
   1358 #else
   1359 		pid = wait(&status);
   1360 #endif
   1361 
   1362 		/*
   1363 		 * return if this would block (0) or no children
   1364 		 * or interrupted (-1)
   1365 		 */
   1366 		if (pid <= 0)
   1367 			goto j_sigchld_out;
   1368 
   1369 		getrusage(RUSAGE_CHILDREN, &ru1);
   1370 
   1371 		/* find job and process structures for this pid */
   1372 		for (j = job_list; j != NULL; j = j->next)
   1373 			for (p = j->proc_list; p != NULL; p = p->next)
   1374 				if (p->pid == pid)
   1375 					goto found;
   1376  found:
   1377 		if (j == NULL) {
   1378 			/* Can occur if process has kids, then execs shell
   1379 			warningf(true, "bad process waited for (pid = %d)",
   1380 				pid);
   1381 			 */
   1382 			ru0 = ru1;
   1383 			continue;
   1384 		}
   1385 
   1386 		timeradd(&j->usrtime, &ru1.ru_utime, &j->usrtime);
   1387 		timersub(&j->usrtime, &ru0.ru_utime, &j->usrtime);
   1388 		timeradd(&j->systime, &ru1.ru_stime, &j->systime);
   1389 		timersub(&j->systime, &ru0.ru_stime, &j->systime);
   1390 		ru0 = ru1;
   1391 		p->status = status;
   1392 #ifndef MKSH_UNEMPLOYED
   1393 		if (WIFSTOPPED(status))
   1394 			p->state = PSTOPPED;
   1395 		else
   1396 #if defined(WCONTINUED) && defined(WIFCONTINUED)
   1397 		  if (WIFCONTINUED(status)) {
   1398 			p->state = j->state = PRUNNING;
   1399 			/* skip check_job(), no-op in this case */
   1400 			continue;
   1401 		} else
   1402 #endif
   1403 #endif
   1404 		  if (WIFSIGNALED(status))
   1405 			p->state = PSIGNALLED;
   1406 		else
   1407 			p->state = PEXITED;
   1408 
   1409 		/* check to see if entire job is done */
   1410 		check_job(j);
   1411 	}
   1412 #ifndef MKSH_NOPROSPECTOFWORK
   1413 	    while (/* CONSTCOND */ 1);
   1414 #else
   1415 	    while (/* CONSTCOND */ 0);
   1416 #endif
   1417 
   1418  j_sigchld_out:
   1419 #ifdef MKSH_NO_SIGSUSPEND
   1420 	sigprocmask(SIG_SETMASK, &omask, NULL);
   1421 #endif
   1422 	errno = saved_errno;
   1423 }
   1424 
   1425 /*
   1426  * Called only when a process in j has exited/stopped (ie, called only
   1427  * from j_sigchld()). If no processes are running, the job status
   1428  * and state are updated, asynchronous job notification is done and,
   1429  * if unneeded, the job is removed.
   1430  *
   1431  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1432  */
   1433 static void
   1434 check_job(Job *j)
   1435 {
   1436 	int jstate;
   1437 	Proc *p;
   1438 
   1439 	/* XXX debugging (nasty - interrupt routine using shl_out) */
   1440 	if (!(j->flags & JF_STARTED)) {
   1441 		internal_warningf("check_job: job started (flags 0x%X)",
   1442 		    (unsigned int)j->flags);
   1443 		return;
   1444 	}
   1445 
   1446 	jstate = PRUNNING;
   1447 	for (p=j->proc_list; p != NULL; p = p->next) {
   1448 		if (p->state == PRUNNING)
   1449 			/* some processes still running */
   1450 			return;
   1451 		if (p->state > jstate)
   1452 			jstate = p->state;
   1453 	}
   1454 	j->state = jstate;
   1455 	j->status = proc_errorlevel(j->last_proc);
   1456 
   1457 	/*
   1458 	 * Note when co-process dies: can't be done in j_wait() nor
   1459 	 * remove_job() since neither may be called for non-interactive
   1460 	 * shells.
   1461 	 */
   1462 	if (j->state == PEXITED || j->state == PSIGNALLED) {
   1463 		/*
   1464 		 * No need to keep co-process input any more
   1465 		 * (at least, this is what ksh93d thinks)
   1466 		 */
   1467 		if (coproc.job == j) {
   1468 			coproc.job = NULL;
   1469 			/*
   1470 			 * XXX would be nice to get the closes out of here
   1471 			 * so they aren't done in the signal handler.
   1472 			 * Would mean a check in coproc_getfd() to
   1473 			 * do "if job == 0 && write >= 0, close write".
   1474 			 */
   1475 			coproc_write_close(coproc.write);
   1476 		}
   1477 		/* Do we need to keep the output? */
   1478 		if (j->coproc_id && j->coproc_id == coproc.id &&
   1479 		    --coproc.njobs == 0)
   1480 			coproc_readw_close(coproc.read);
   1481 	}
   1482 
   1483 	j->flags |= JF_CHANGED;
   1484 #ifndef MKSH_UNEMPLOYED
   1485 	if (Flag(FMONITOR) && !(j->flags & JF_XXCOM)) {
   1486 		/*
   1487 		 * Only put stopped jobs at the front to avoid confusing
   1488 		 * the user (don't want finished jobs effecting %+ or %-)
   1489 		 */
   1490 		if (j->state == PSTOPPED)
   1491 			put_job(j, PJ_ON_FRONT);
   1492 		if (Flag(FNOTIFY) &&
   1493 		    (j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY)) != JF_WAITING) {
   1494 			/* Look for the real file descriptor 2 */
   1495 			{
   1496 				struct env *ep;
   1497 				int fd = 2;
   1498 
   1499 				for (ep = e; ep; ep = ep->oenv)
   1500 					if (ep->savefd && ep->savefd[2])
   1501 						fd = ep->savefd[2];
   1502 				shf_reopen(fd, SHF_WR, shl_j);
   1503 			}
   1504 			/*
   1505 			 * Can't call j_notify() as it removes jobs. The job
   1506 			 * must stay in the job list as j_waitj() may be
   1507 			 * running with this job.
   1508 			 */
   1509 			j_print(j, JP_MEDIUM, shl_j);
   1510 			shf_flush(shl_j);
   1511 			if (!(j->flags & JF_WAITING) && j->state != PSTOPPED)
   1512 				remove_job(j, "notify");
   1513 		}
   1514 	}
   1515 #endif
   1516 	if (
   1517 #ifndef MKSH_UNEMPLOYED
   1518 	    !Flag(FMONITOR) &&
   1519 #endif
   1520 	    !(j->flags & (JF_WAITING|JF_FG)) &&
   1521 	    j->state != PSTOPPED) {
   1522 		if (j == async_job || (j->flags & JF_KNOWN)) {
   1523 			j->flags |= JF_ZOMBIE;
   1524 			j->job = -1;
   1525 			nzombie++;
   1526 		} else
   1527 			remove_job(j, "checkjob");
   1528 	}
   1529 }
   1530 
   1531 /*
   1532  * Print job status in either short, medium or long format.
   1533  *
   1534  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1535  */
   1536 static void
   1537 j_print(Job *j, int how, struct shf *shf)
   1538 {
   1539 	Proc *p;
   1540 	int state;
   1541 	int status;
   1542 #ifdef WCOREDUMP
   1543 	bool coredumped;
   1544 #endif
   1545 	char jobchar = ' ';
   1546 	char buf[64];
   1547 	const char *filler;
   1548 	int output = 0;
   1549 
   1550 	if (how == JP_PGRP) {
   1551 		/*
   1552 		 * POSIX doesn't say what to do it there is no process
   1553 		 * group leader (ie, !FMONITOR). We arbitrarily return
   1554 		 * last pid (which is what $! returns).
   1555 		 */
   1556 		shf_fprintf(shf, Tf_dN, (int)(j->pgrp ? j->pgrp :
   1557 		    (j->last_proc ? j->last_proc->pid : 0)));
   1558 		return;
   1559 	}
   1560 	j->flags &= ~JF_CHANGED;
   1561 	filler = j->job > 10 ? "\n       " : "\n      ";
   1562 	if (j == job_list)
   1563 		jobchar = '+';
   1564 	else if (j == job_list->next)
   1565 		jobchar = '-';
   1566 
   1567 	for (p = j->proc_list; p != NULL;) {
   1568 #ifdef WCOREDUMP
   1569 		coredumped = false;
   1570 #endif
   1571 		switch (p->state) {
   1572 		case PRUNNING:
   1573 			memcpy(buf, "Running", 8);
   1574 			break;
   1575 		case PSTOPPED: {
   1576 			int stopsig = WSTOPSIG(p->status);
   1577 
   1578 			strlcpy(buf, stopsig > 0 && stopsig < ksh_NSIG ?
   1579 			    sigtraps[stopsig].mess : "Stopped", sizeof(buf));
   1580 			break;
   1581 		}
   1582 		case PEXITED: {
   1583 			int exitstatus = (WEXITSTATUS(p->status)) & 255;
   1584 
   1585 			if (how == JP_SHORT)
   1586 				buf[0] = '\0';
   1587 			else if (exitstatus == 0)
   1588 				memcpy(buf, "Done", 5);
   1589 			else
   1590 				shf_snprintf(buf, sizeof(buf), "Done (%d)",
   1591 				    exitstatus);
   1592 			break;
   1593 		}
   1594 		case PSIGNALLED: {
   1595 			int termsig = WTERMSIG(p->status);
   1596 #ifdef WCOREDUMP
   1597 			if (WCOREDUMP(p->status))
   1598 				coredumped = true;
   1599 #endif
   1600 			/*
   1601 			 * kludge for not reporting 'normal termination
   1602 			 * signals' (i.e. SIGINT, SIGPIPE)
   1603 			 */
   1604 			if (how == JP_SHORT &&
   1605 #ifdef WCOREDUMP
   1606 			    !coredumped &&
   1607 #endif
   1608 			    (termsig == SIGINT || termsig == SIGPIPE)) {
   1609 				buf[0] = '\0';
   1610 			} else
   1611 				strlcpy(buf, termsig > 0 && termsig < ksh_NSIG ?
   1612 				    sigtraps[termsig].mess : "Signalled",
   1613 				    sizeof(buf));
   1614 			break;
   1615 		}
   1616 		default:
   1617 			buf[0] = '\0';
   1618 		}
   1619 
   1620 		if (how != JP_SHORT) {
   1621 			if (p == j->proc_list)
   1622 				shf_fprintf(shf, "[%d] %c ", j->job, jobchar);
   1623 			else
   1624 				shf_puts(filler, shf);
   1625 		}
   1626 
   1627 		if (how == JP_LONG)
   1628 			shf_fprintf(shf, "%5d ", (int)p->pid);
   1629 
   1630 		if (how == JP_SHORT) {
   1631 			if (buf[0]) {
   1632 				output = 1;
   1633 #ifdef WCOREDUMP
   1634 				shf_fprintf(shf, "%s%s ",
   1635 				    buf, coredumped ? " (core dumped)" : null);
   1636 #else
   1637 				shf_puts(buf, shf);
   1638 				shf_putchar(' ', shf);
   1639 #endif
   1640 			}
   1641 		} else {
   1642 			output = 1;
   1643 			shf_fprintf(shf, "%-20s %s%s%s", buf, p->command,
   1644 			    p->next ? "|" : null,
   1645 #ifdef WCOREDUMP
   1646 			    coredumped ? " (core dumped)" :
   1647 #endif
   1648 			     null);
   1649 		}
   1650 
   1651 		state = p->state;
   1652 		status = p->status;
   1653 		p = p->next;
   1654 		while (p && p->state == state && p->status == status) {
   1655 			if (how == JP_LONG)
   1656 				shf_fprintf(shf, "%s%5d %-20s %s%s", filler,
   1657 				    (int)p->pid, T1space, p->command,
   1658 				    p->next ? "|" : null);
   1659 			else if (how == JP_MEDIUM)
   1660 				shf_fprintf(shf, Tf__ss, p->command,
   1661 				    p->next ? "|" : null);
   1662 			p = p->next;
   1663 		}
   1664 	}
   1665 	if (output)
   1666 		shf_putc('\n', shf);
   1667 }
   1668 
   1669 /*
   1670  * Convert % sequence to job
   1671  *
   1672  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1673  */
   1674 static Job *
   1675 j_lookup(const char *cp, int *ecodep)
   1676 {
   1677 	Job *j, *last_match;
   1678 	Proc *p;
   1679 	size_t len;
   1680 	int job = 0;
   1681 
   1682 	if (ctype(*cp, C_DIGIT) && getn(cp, &job)) {
   1683 		/* Look for last_proc->pid (what $! returns) first... */
   1684 		for (j = job_list; j != NULL; j = j->next)
   1685 			if (j->last_proc && j->last_proc->pid == job)
   1686 				return (j);
   1687 		/*
   1688 		 * ...then look for process group (this is non-POSIX,
   1689 		 * but should not break anything
   1690 		 */
   1691 		for (j = job_list; j != NULL; j = j->next)
   1692 			if (j->pgrp && j->pgrp == job)
   1693 				return (j);
   1694 		goto j_lookup_nosuch;
   1695 	}
   1696 	if (*cp != '%') {
   1697  j_lookup_invalid:
   1698 		if (ecodep)
   1699 			*ecodep = JL_INVALID;
   1700 		return (NULL);
   1701 	}
   1702 	switch (*++cp) {
   1703 	case '\0': /* non-standard */
   1704 	case '+':
   1705 	case '%':
   1706 		if (job_list != NULL)
   1707 			return (job_list);
   1708 		break;
   1709 
   1710 	case '-':
   1711 		if (job_list != NULL && job_list->next)
   1712 			return (job_list->next);
   1713 		break;
   1714 
   1715 	case '0': case '1': case '2': case '3': case '4':
   1716 	case '5': case '6': case '7': case '8': case '9':
   1717 		if (!getn(cp, &job))
   1718 			goto j_lookup_invalid;
   1719 		for (j = job_list; j != NULL; j = j->next)
   1720 			if (j->job == job)
   1721 				return (j);
   1722 		break;
   1723 
   1724 	/* %?string */
   1725 	case '?':
   1726 		last_match = NULL;
   1727 		for (j = job_list; j != NULL; j = j->next)
   1728 			for (p = j->proc_list; p != NULL; p = p->next)
   1729 				if (strstr(p->command, cp+1) != NULL) {
   1730 					if (last_match) {
   1731 						if (ecodep)
   1732 							*ecodep = JL_AMBIG;
   1733 						return (NULL);
   1734 					}
   1735 					last_match = j;
   1736 				}
   1737 		if (last_match)
   1738 			return (last_match);
   1739 		break;
   1740 
   1741 	/* %string */
   1742 	default:
   1743 		len = strlen(cp);
   1744 		last_match = NULL;
   1745 		for (j = job_list; j != NULL; j = j->next)
   1746 			if (strncmp(cp, j->proc_list->command, len) == 0) {
   1747 				if (last_match) {
   1748 					if (ecodep)
   1749 						*ecodep = JL_AMBIG;
   1750 					return (NULL);
   1751 				}
   1752 				last_match = j;
   1753 			}
   1754 		if (last_match)
   1755 			return (last_match);
   1756 		break;
   1757 	}
   1758  j_lookup_nosuch:
   1759 	if (ecodep)
   1760 		*ecodep = JL_NOSUCH;
   1761 	return (NULL);
   1762 }
   1763 
   1764 static Job	*free_jobs;
   1765 static Proc	*free_procs;
   1766 
   1767 /*
   1768  * allocate a new job and fill in the job number.
   1769  *
   1770  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1771  */
   1772 static Job *
   1773 new_job(void)
   1774 {
   1775 	int i;
   1776 	Job *newj, *j;
   1777 
   1778 	if (free_jobs != NULL) {
   1779 		newj = free_jobs;
   1780 		free_jobs = free_jobs->next;
   1781 	} else
   1782 		newj = alloc(sizeof(Job), APERM);
   1783 
   1784 	/* brute force method */
   1785 	for (i = 1; ; i++) {
   1786 		for (j = job_list; j && j->job != i; j = j->next)
   1787 			;
   1788 		if (j == NULL)
   1789 			break;
   1790 	}
   1791 	newj->job = i;
   1792 
   1793 	return (newj);
   1794 }
   1795 
   1796 /*
   1797  * Allocate new process struct
   1798  *
   1799  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1800  */
   1801 static Proc *
   1802 new_proc(void)
   1803 {
   1804 	Proc *p;
   1805 
   1806 	if (free_procs != NULL) {
   1807 		p = free_procs;
   1808 		free_procs = free_procs->next;
   1809 	} else
   1810 		p = alloc(sizeof(Proc), APERM);
   1811 
   1812 	return (p);
   1813 }
   1814 
   1815 /*
   1816  * Take job out of job_list and put old structures into free list.
   1817  * Keeps nzombies, last_job and async_job up to date.
   1818  *
   1819  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1820  */
   1821 static void
   1822 remove_job(Job *j, const char *where)
   1823 {
   1824 	Proc *p, *tmp;
   1825 	Job **prev, *curr;
   1826 
   1827 	prev = &job_list;
   1828 	curr = job_list;
   1829 	while (curr && curr != j) {
   1830 		prev = &curr->next;
   1831 		curr = *prev;
   1832 	}
   1833 	if (curr != j) {
   1834 		internal_warningf("remove_job: job %s (%s)", Tnot_found, where);
   1835 		return;
   1836 	}
   1837 	*prev = curr->next;
   1838 
   1839 	/* free up proc structures */
   1840 	for (p = j->proc_list; p != NULL; ) {
   1841 		tmp = p;
   1842 		p = p->next;
   1843 		tmp->next = free_procs;
   1844 		free_procs = tmp;
   1845 	}
   1846 
   1847 	if ((j->flags & JF_ZOMBIE) && j->ppid == procpid)
   1848 		--nzombie;
   1849 	j->next = free_jobs;
   1850 	free_jobs = j;
   1851 
   1852 	if (j == last_job)
   1853 		last_job = NULL;
   1854 	if (j == async_job)
   1855 		async_job = NULL;
   1856 }
   1857 
   1858 /*
   1859  * put j in a particular location (taking it out job_list if it is there
   1860  * already)
   1861  *
   1862  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1863  */
   1864 static void
   1865 put_job(Job *j, int where)
   1866 {
   1867 	Job **prev, *curr;
   1868 
   1869 	/* Remove job from list (if there) */
   1870 	prev = &job_list;
   1871 	curr = job_list;
   1872 	while (curr && curr != j) {
   1873 		prev = &curr->next;
   1874 		curr = *prev;
   1875 	}
   1876 	if (curr == j)
   1877 		*prev = curr->next;
   1878 
   1879 	switch (where) {
   1880 	case PJ_ON_FRONT:
   1881 		j->next = job_list;
   1882 		job_list = j;
   1883 		break;
   1884 
   1885 	case PJ_PAST_STOPPED:
   1886 		prev = &job_list;
   1887 		curr = job_list;
   1888 		for (; curr && curr->state == PSTOPPED; prev = &curr->next,
   1889 		    curr = *prev)
   1890 			;
   1891 		j->next = curr;
   1892 		*prev = j;
   1893 		break;
   1894 	}
   1895 }
   1896 
   1897 /*
   1898  * nuke a job (called when unable to start full job).
   1899  *
   1900  * If jobs are compiled in then this routine expects sigchld to be blocked.
   1901  */
   1902 static int
   1903 kill_job(Job *j, int sig)
   1904 {
   1905 	Proc *p;
   1906 	int rval = 0;
   1907 
   1908 	for (p = j->proc_list; p != NULL; p = p->next)
   1909 		if (p->pid != 0)
   1910 			if (kill(p->pid, sig) < 0)
   1911 				rval = -1;
   1912 	return (rval);
   1913 }
   1914 
   1915 static void
   1916 tty_init_talking(void)
   1917 {
   1918 	switch (tty_init_fd()) {
   1919 	case 0:
   1920 		break;
   1921 	case 1:
   1922 #ifndef MKSH_DISABLE_TTY_WARNING
   1923 		warningf(false, Tf_sD_s_sD_s,
   1924 		    "No controlling tty", Topen, T_devtty, cstrerror(errno));
   1925 #endif
   1926 		break;
   1927 	case 2:
   1928 #ifndef MKSH_DISABLE_TTY_WARNING
   1929 		warningf(false, Tf_s_sD_s, Tcant_find, Ttty_fd,
   1930 		    cstrerror(errno));
   1931 #endif
   1932 		break;
   1933 	case 3:
   1934 		warningf(false, Tf_ssfaileds, "j_ttyinit",
   1935 		    Ttty_fd_dupof, cstrerror(errno));
   1936 		break;
   1937 	case 4:
   1938 		warningf(false, Tf_sD_sD_s, "j_ttyinit",
   1939 		    "can't set close-on-exec flag", cstrerror(errno));
   1940 		break;
   1941 	}
   1942 }
   1943 
   1944 static void
   1945 tty_init_state(void)
   1946 {
   1947 	if (tty_fd >= 0) {
   1948 		mksh_tcget(tty_fd, &tty_state);
   1949 		tty_hasstate = true;
   1950 	}
   1951 }
   1952