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-rw-r--r--bin/1sh/jobs.c1569
1 files changed, 0 insertions, 1569 deletions
diff --git a/bin/1sh/jobs.c b/bin/1sh/jobs.c
deleted file mode 100644
index 492251e0..00000000
--- a/bin/1sh/jobs.c
+++ /dev/null
@@ -1,1569 +0,0 @@
-/*-
- * Copyright (c) 1991, 1993
- *	The Regents of the University of California.  All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Kenneth Almquist.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#ifndef lint
-#if 0
-static char sccsid[] = "@(#)jobs.c	8.5 (Berkeley) 5/4/95";
-#endif
-#endif /* not lint */
-#include <sys/cdefs.h>
-/* $FreeBSD: releng/12.1/bin/sh/jobs.c 345487 2019-03-24 22:10:26Z jilles $ */
-
-#include <sys/ioctl.h>
-#include <sys/param.h>
-#include <sys/resource.h>
-#include <sys/time.h>
-#include <sys/wait.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <paths.h>
-#include <signal.h>
-#include <stddef.h>
-#include <stdlib.h>
-#include <unistd.h>
-
-#include "shell.h"
-#if JOBS
-#include <termios.h>
-#undef CEOF			/* syntax.h redefines this */
-#endif
-#include "redir.h"
-#include "exec.h"
-#include "show.h"
-#include "main.h"
-#include "parser.h"
-#include "nodes.h"
-#include "jobs.h"
-#include "options.h"
-#include "trap.h"
-#include "syntax.h"
-#include "input.h"
-#include "output.h"
-#include "memalloc.h"
-#include "error.h"
-#include "mystring.h"
-#include "var.h"
-#include "builtins.h"
-
-
-/*
- * A job structure contains information about a job.  A job is either a
- * single process or a set of processes contained in a pipeline.  In the
- * latter case, pidlist will be non-NULL, and will point to a -1 terminated
- * array of pids.
- */
-
-struct procstat {
-	pid_t pid;		/* process id */
-	int status;		/* status flags (defined above) */
-	char *cmd;		/* text of command being run */
-};
-
-
-/* states */
-#define JOBSTOPPED 1		/* all procs are stopped */
-#define JOBDONE 2		/* all procs are completed */
-
-
-struct job {
-	struct procstat ps0;	/* status of process */
-	struct procstat *ps;	/* status or processes when more than one */
-	short nprocs;		/* number of processes */
-	pid_t pgrp;		/* process group of this job */
-	char state;		/* true if job is finished */
-	char used;		/* true if this entry is in used */
-	char changed;		/* true if status has changed */
-	char foreground;	/* true if running in the foreground */
-	char remembered;	/* true if $! referenced */
-	char pipefail;		/* pass any non-zero status */
-#if JOBS
-	char jobctl;		/* job running under job control */
-	struct job *next;	/* job used after this one */
-#endif
-};
-
-
-static struct job *jobtab;	/* array of jobs */
-static int njobs;		/* size of array */
-static pid_t backgndpid = -1;	/* pid of last background process */
-static struct job *bgjob = NULL; /* last background process */
-#if JOBS
-static struct job *jobmru;	/* most recently used job list */
-static pid_t initialpgrp;	/* pgrp of shell on invocation */
-#endif
-static int ttyfd = -1;
-
-/* mode flags for dowait */
-#define DOWAIT_BLOCK	0x1 /* wait until a child exits */
-#define DOWAIT_SIG	0x2 /* if DOWAIT_BLOCK, abort on signal */
-#define DOWAIT_SIG_TRAP	0x4 /* if DOWAIT_SIG, abort on trapped signal only */
-
-#if JOBS
-static void restartjob(struct job *);
-#endif
-static void freejob(struct job *);
-static int waitcmdloop(struct job *);
-static struct job *getjob_nonotfound(const char *);
-static struct job *getjob(const char *);
-pid_t killjob(const char *, int);
-static pid_t dowait(int, struct job *);
-static void checkzombies(void);
-static void cmdtxt(union node *);
-static void cmdputs(const char *);
-#if JOBS
-static void setcurjob(struct job *);
-static void deljob(struct job *);
-static struct job *getcurjob(struct job *);
-#endif
-static int getjobstatus(const struct job *);
-static void printjobcmd(struct job *);
-static void showjob(struct job *, int);
-
-
-/*
- * Turn job control on and off.
- */
-
-static int jobctl;
-
-#if JOBS
-static void
-jobctl_notty(void)
-{
-	if (ttyfd >= 0) {
-		close(ttyfd);
-		ttyfd = -1;
-	}
-	if (!iflag) {
-		setsignal(SIGTSTP);
-		setsignal(SIGTTOU);
-		setsignal(SIGTTIN);
-		jobctl = 1;
-		return;
-	}
-	out2fmt_flush("sh: can't access tty; job control turned off\n");
-	mflag = 0;
-}
-
-void
-setjobctl(int on)
-{
-	int i;
-
-	if (on == jobctl || rootshell == 0)
-		return;
-	if (on) {
-		if (ttyfd != -1)
-			close(ttyfd);
-		if ((ttyfd = open(_PATH_TTY, O_RDWR | O_CLOEXEC)) < 0) {
-			i = 0;
-			while (i <= 2 && !isatty(i))
-				i++;
-			if (i > 2 ||
-			    (ttyfd = fcntl(i, F_DUPFD_CLOEXEC, 10)) < 0) {
-				jobctl_notty();
-				return;
-			}
-		}
-		if (ttyfd < 10) {
-			/*
-			 * Keep our TTY file descriptor out of the way of
-			 * the user's redirections.
-			 */
-			if ((i = fcntl(ttyfd, F_DUPFD_CLOEXEC, 10)) < 0) {
-				jobctl_notty();
-				return;
-			}
-			close(ttyfd);
-			ttyfd = i;
-		}
-		do { /* while we are in the background */
-			initialpgrp = tcgetpgrp(ttyfd);
-			if (initialpgrp < 0) {
-				jobctl_notty();
-				return;
-			}
-			if (initialpgrp != getpgrp()) {
-				if (!iflag) {
-					initialpgrp = -1;
-					jobctl_notty();
-					return;
-				}
-				kill(0, SIGTTIN);
-				continue;
-			}
-		} while (0);
-		setsignal(SIGTSTP);
-		setsignal(SIGTTOU);
-		setsignal(SIGTTIN);
-		setpgid(0, rootpid);
-		tcsetpgrp(ttyfd, rootpid);
-	} else { /* turning job control off */
-		setpgid(0, initialpgrp);
-		if (ttyfd >= 0) {
-			tcsetpgrp(ttyfd, initialpgrp);
-			close(ttyfd);
-			ttyfd = -1;
-		}
-		setsignal(SIGTSTP);
-		setsignal(SIGTTOU);
-		setsignal(SIGTTIN);
-	}
-	jobctl = on;
-}
-#endif
-
-
-#if JOBS
-int
-fgcmd(int argc __unused, char **argv __unused)
-{
-	struct job *jp;
-	pid_t pgrp;
-	int status;
-
-	nextopt("");
-	jp = getjob(*argptr);
-	if (jp->jobctl == 0)
-		error("job not created under job control");
-	printjobcmd(jp);
-	flushout(&output);
-	pgrp = jp->ps[0].pid;
-	if (ttyfd >= 0)
-		tcsetpgrp(ttyfd, pgrp);
-	restartjob(jp);
-	jp->foreground = 1;
-	INTOFF;
-	status = waitforjob(jp, (int *)NULL);
-	INTON;
-	return status;
-}
-
-
-int
-bgcmd(int argc __unused, char **argv __unused)
-{
-	struct job *jp;
-
-	nextopt("");
-	do {
-		jp = getjob(*argptr);
-		if (jp->jobctl == 0)
-			error("job not created under job control");
-		if (jp->state == JOBDONE)
-			continue;
-		restartjob(jp);
-		jp->foreground = 0;
-		out1fmt("[%td] ", jp - jobtab + 1);
-		printjobcmd(jp);
-	} while (*argptr != NULL && *++argptr != NULL);
-	return 0;
-}
-
-
-static void
-restartjob(struct job *jp)
-{
-	struct procstat *ps;
-	int i;
-
-	if (jp->state == JOBDONE)
-		return;
-	setcurjob(jp);
-	INTOFF;
-	kill(-jp->ps[0].pid, SIGCONT);
-	for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
-		if (WIFSTOPPED(ps->status)) {
-			ps->status = -1;
-			jp->state = 0;
-		}
-	}
-	INTON;
-}
-#endif
-
-
-int
-jobscmd(int argc __unused, char *argv[] __unused)
-{
-	char *id;
-	int ch, mode;
-
-	mode = SHOWJOBS_DEFAULT;
-	while ((ch = nextopt("lps")) != '\0') {
-		switch (ch) {
-		case 'l':
-			mode = SHOWJOBS_VERBOSE;
-			break;
-		case 'p':
-			mode = SHOWJOBS_PGIDS;
-			break;
-		case 's':
-			mode = SHOWJOBS_PIDS;
-			break;
-		}
-	}
-
-	if (*argptr == NULL)
-		showjobs(0, mode);
-	else
-		while ((id = *argptr++) != NULL)
-			showjob(getjob(id), mode);
-
-	return (0);
-}
-
-static int getjobstatus(const struct job *jp)
-{
-	int i, status;
-
-	if (!jp->pipefail)
-		return (jp->ps[jp->nprocs - 1].status);
-	for (i = jp->nprocs - 1; i >= 0; i--) {
-		status = jp->ps[i].status;
-		if (status != 0)
-			return (status);
-	}
-	return (0);
-}
-
-static void
-printjobcmd(struct job *jp)
-{
-	struct procstat *ps;
-	int i;
-
-	for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
-		out1str(ps->cmd);
-		if (i > 0)
-			out1str(" | ");
-	}
-	out1c('\n');
-}
-
-static void
-showjob(struct job *jp, int mode)
-{
-	char s[64];
-	char statebuf[16];
-	const char *statestr, *coredump;
-	struct procstat *ps;
-	struct job *j;
-	int col, curr, i, jobno, prev, procno, status;
-	char c;
-
-	procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs;
-	jobno = jp - jobtab + 1;
-	curr = prev = 0;
-#if JOBS
-	if ((j = getcurjob(NULL)) != NULL) {
-		curr = j - jobtab + 1;
-		if ((j = getcurjob(j)) != NULL)
-			prev = j - jobtab + 1;
-	}
-#endif
-	coredump = "";
-	status = getjobstatus(jp);
-	if (jp->state == 0) {
-		statestr = "Running";
-#if JOBS
-	} else if (jp->state == JOBSTOPPED) {
-		ps = jp->ps + jp->nprocs - 1;
-		while (!WIFSTOPPED(ps->status) && ps > jp->ps)
-			ps--;
-		if (WIFSTOPPED(ps->status))
-			i = WSTOPSIG(ps->status);
-		else
-			i = -1;
-		statestr = strsignal(i);
-		if (statestr == NULL)
-			statestr = "Suspended";
-#endif
-	} else if (WIFEXITED(status)) {
-		if (WEXITSTATUS(status) == 0)
-			statestr = "Done";
-		else {
-			fmtstr(statebuf, sizeof(statebuf), "Done(%d)",
-			    WEXITSTATUS(status));
-			statestr = statebuf;
-		}
-	} else {
-		i = WTERMSIG(status);
-		statestr = strsignal(i);
-		if (statestr == NULL)
-			statestr = "Unknown signal";
-		if (WCOREDUMP(status))
-			coredump = " (core dumped)";
-	}
-
-	for (ps = jp->ps ; procno > 0 ; ps++, procno--) { /* for each process */
-		if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) {
-			out1fmt("%d\n", (int)ps->pid);
-			continue;
-		}
-		if (mode != SHOWJOBS_VERBOSE && ps != jp->ps)
-			continue;
-		if (jobno == curr && ps == jp->ps)
-			c = '+';
-		else if (jobno == prev && ps == jp->ps)
-			c = '-';
-		else
-			c = ' ';
-		if (ps == jp->ps)
-			fmtstr(s, 64, "[%d] %c ", jobno, c);
-		else
-			fmtstr(s, 64, "    %c ", c);
-		out1str(s);
-		col = strlen(s);
-		if (mode == SHOWJOBS_VERBOSE) {
-			fmtstr(s, 64, "%d ", (int)ps->pid);
-			out1str(s);
-			col += strlen(s);
-		}
-		if (ps == jp->ps) {
-			out1str(statestr);
-			out1str(coredump);
-			col += strlen(statestr) + strlen(coredump);
-		}
-		do {
-			out1c(' ');
-			col++;
-		} while (col < 30);
-		if (mode == SHOWJOBS_VERBOSE) {
-			out1str(ps->cmd);
-			out1c('\n');
-		} else
-			printjobcmd(jp);
-	}
-}
-
-/*
- * Print a list of jobs.  If "change" is nonzero, only print jobs whose
- * statuses have changed since the last call to showjobs.
- *
- * If the shell is interrupted in the process of creating a job, the
- * result may be a job structure containing zero processes.  Such structures
- * will be freed here.
- */
-
-void
-showjobs(int change, int mode)
-{
-	int jobno;
-	struct job *jp;
-
-	TRACE(("showjobs(%d) called\n", change));
-	checkzombies();
-	for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) {
-		if (! jp->used)
-			continue;
-		if (jp->nprocs == 0) {
-			freejob(jp);
-			continue;
-		}
-		if (change && ! jp->changed)
-			continue;
-		showjob(jp, mode);
-		if (mode == SHOWJOBS_DEFAULT || mode == SHOWJOBS_VERBOSE) {
-			jp->changed = 0;
-			/* Hack: discard jobs for which $! has not been
-			 * referenced in interactive mode when they terminate.
-			 */
-			if (jp->state == JOBDONE && !jp->remembered &&
-					(iflag || jp != bgjob)) {
-				freejob(jp);
-			}
-		}
-	}
-}
-
-
-/*
- * Mark a job structure as unused.
- */
-
-static void
-freejob(struct job *jp)
-{
-	struct procstat *ps;
-	int i;
-
-	INTOFF;
-	if (bgjob == jp)
-		bgjob = NULL;
-	for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) {
-		if (ps->cmd != nullstr)
-			ckfree(ps->cmd);
-	}
-	if (jp->ps != &jp->ps0)
-		ckfree(jp->ps);
-	jp->used = 0;
-#if JOBS
-	deljob(jp);
-#endif
-	INTON;
-}
-
-
-
-int
-waitcmd(int argc __unused, char **argv __unused)
-{
-	struct job *job;
-	int retval;
-
-	nextopt("");
-	if (*argptr == NULL)
-		return (waitcmdloop(NULL));
-
-	do {
-		job = getjob_nonotfound(*argptr);
-		if (job == NULL)
-			retval = 127;
-		else
-			retval = waitcmdloop(job);
-		argptr++;
-	} while (*argptr != NULL);
-
-	return (retval);
-}
-
-static int
-waitcmdloop(struct job *job)
-{
-	int status, retval, sig;
-	struct job *jp;
-
-	/*
-	 * Loop until a process is terminated or stopped, or a SIGINT is
-	 * received.
-	 */
-
-	do {
-		if (job != NULL) {
-			if (job->state == JOBDONE) {
-				status = getjobstatus(job);
-				if (WIFEXITED(status))
-					retval = WEXITSTATUS(status);
-				else
-					retval = WTERMSIG(status) + 128;
-				if (! iflag || ! job->changed)
-					freejob(job);
-				else {
-					job->remembered = 0;
-					if (job == bgjob)
-						bgjob = NULL;
-				}
-				return retval;
-			}
-		} else {
-			for (jp = jobtab ; jp < jobtab + njobs; jp++)
-				if (jp->used && jp->state == JOBDONE) {
-					if (! iflag || ! jp->changed)
-						freejob(jp);
-					else {
-						jp->remembered = 0;
-						if (jp == bgjob)
-							bgjob = NULL;
-					}
-				}
-			for (jp = jobtab ; ; jp++) {
-				if (jp >= jobtab + njobs) {	/* no running procs */
-					return 0;
-				}
-				if (jp->used && jp->state == 0)
-					break;
-			}
-		}
-	} while (dowait(DOWAIT_BLOCK | DOWAIT_SIG, (struct job *)NULL) != -1);
-
-	sig = pendingsig_waitcmd;
-	pendingsig_waitcmd = 0;
-	return sig + 128;
-}
-
-
-
-int
-jobidcmd(int argc __unused, char **argv __unused)
-{
-	struct job *jp;
-	int i;
-
-	nextopt("");
-	jp = getjob(*argptr);
-	for (i = 0 ; i < jp->nprocs ; ) {
-		out1fmt("%d", (int)jp->ps[i].pid);
-		out1c(++i < jp->nprocs? ' ' : '\n');
-	}
-	return 0;
-}
-
-
-
-/*
- * Convert a job name to a job structure.
- */
-
-static struct job *
-getjob_nonotfound(const char *name)
-{
-	int jobno;
-	struct job *found, *jp;
-	size_t namelen;
-	pid_t pid;
-	int i;
-
-	if (name == NULL) {
-#if JOBS
-		name = "%+";
-#else
-		error("No current job");
-#endif
-	}
-	if (name[0] == '%') {
-		if (is_digit(name[1])) {
-			jobno = number(name + 1);
-			if (jobno > 0 && jobno <= njobs
-			 && jobtab[jobno - 1].used != 0)
-				return &jobtab[jobno - 1];
-#if JOBS
-		} else if ((name[1] == '%' || name[1] == '+') &&
-		    name[2] == '\0') {
-			if ((jp = getcurjob(NULL)) == NULL)
-				error("No current job");
-			return (jp);
-		} else if (name[1] == '-' && name[2] == '\0') {
-			if ((jp = getcurjob(NULL)) == NULL ||
-			    (jp = getcurjob(jp)) == NULL)
-				error("No previous job");
-			return (jp);
-#endif
-		} else if (name[1] == '?') {
-			found = NULL;
-			for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
-				if (jp->used && jp->nprocs > 0
-				 && strstr(jp->ps[0].cmd, name + 2) != NULL) {
-					if (found)
-						error("%s: ambiguous", name);
-					found = jp;
-				}
-			}
-			if (found != NULL)
-				return (found);
-		} else {
-			namelen = strlen(name);
-			found = NULL;
-			for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
-				if (jp->used && jp->nprocs > 0
-				 && strncmp(jp->ps[0].cmd, name + 1,
-				 namelen - 1) == 0) {
-					if (found)
-						error("%s: ambiguous", name);
-					found = jp;
-				}
-			}
-			if (found)
-				return found;
-		}
-	} else if (is_number(name)) {
-		pid = (pid_t)number(name);
-		for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
-			if (jp->used && jp->nprocs > 0
-			 && jp->ps[jp->nprocs - 1].pid == pid)
-				return jp;
-		}
-	}
-	return NULL;
-}
-
-
-static struct job *
-getjob(const char *name)
-{
-	struct job *jp;
-
-	jp = getjob_nonotfound(name);
-	if (jp == NULL)
-		error("No such job: %s", name);
-	return (jp);
-}
-
-
-int
-killjob(const char *name, int sig)
-{
-	struct job *jp;
-	int i, ret;
-
-	jp = getjob(name);
-	if (jp->state == JOBDONE)
-		return 0;
-	if (jp->jobctl)
-		return kill(-jp->ps[0].pid, sig);
-	ret = -1;
-	errno = ESRCH;
-	for (i = 0; i < jp->nprocs; i++)
-		if (jp->ps[i].status == -1 || WIFSTOPPED(jp->ps[i].status)) {
-			if (kill(jp->ps[i].pid, sig) == 0)
-				ret = 0;
-		} else
-			ret = 0;
-	return ret;
-}
-
-/*
- * Return a new job structure,
- */
-
-struct job *
-makejob(union node *node __unused, int nprocs)
-{
-	int i;
-	struct job *jp;
-
-	for (i = njobs, jp = jobtab ; ; jp++) {
-		if (--i < 0) {
-			INTOFF;
-			if (njobs == 0) {
-				jobtab = ckmalloc(4 * sizeof jobtab[0]);
-#if JOBS
-				jobmru = NULL;
-#endif
-			} else {
-				jp = ckmalloc((njobs + 4) * sizeof jobtab[0]);
-				memcpy(jp, jobtab, njobs * sizeof jp[0]);
-#if JOBS
-				/* Relocate `next' pointers and list head */
-				if (jobmru != NULL)
-					jobmru = &jp[jobmru - jobtab];
-				for (i = 0; i < njobs; i++)
-					if (jp[i].next != NULL)
-						jp[i].next = &jp[jp[i].next -
-						    jobtab];
-#endif
-				if (bgjob != NULL)
-					bgjob = &jp[bgjob - jobtab];
-				/* Relocate `ps' pointers */
-				for (i = 0; i < njobs; i++)
-					if (jp[i].ps == &jobtab[i].ps0)
-						jp[i].ps = &jp[i].ps0;
-				ckfree(jobtab);
-				jobtab = jp;
-			}
-			jp = jobtab + njobs;
-			for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0)
-				;
-			INTON;
-			break;
-		}
-		if (jp->used == 0)
-			break;
-	}
-	INTOFF;
-	jp->state = 0;
-	jp->used = 1;
-	jp->changed = 0;
-	jp->nprocs = 0;
-	jp->foreground = 0;
-	jp->remembered = 0;
-	jp->pipefail = pipefailflag;
-#if JOBS
-	jp->jobctl = jobctl;
-	jp->next = NULL;
-#endif
-	if (nprocs > 1) {
-		jp->ps = ckmalloc(nprocs * sizeof (struct procstat));
-	} else {
-		jp->ps = &jp->ps0;
-	}
-	INTON;
-	TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs,
-	    jp - jobtab + 1));
-	return jp;
-}
-
-#if JOBS
-static void
-setcurjob(struct job *cj)
-{
-	struct job *jp, *prev;
-
-	for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
-		if (jp == cj) {
-			if (prev != NULL)
-				prev->next = jp->next;
-			else
-				jobmru = jp->next;
-			jp->next = jobmru;
-			jobmru = cj;
-			return;
-		}
-	}
-	cj->next = jobmru;
-	jobmru = cj;
-}
-
-static void
-deljob(struct job *j)
-{
-	struct job *jp, *prev;
-
-	for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
-		if (jp == j) {
-			if (prev != NULL)
-				prev->next = jp->next;
-			else
-				jobmru = jp->next;
-			return;
-		}
-	}
-}
-
-/*
- * Return the most recently used job that isn't `nj', and preferably one
- * that is stopped.
- */
-static struct job *
-getcurjob(struct job *nj)
-{
-	struct job *jp;
-
-	/* Try to find a stopped one.. */
-	for (jp = jobmru; jp != NULL; jp = jp->next)
-		if (jp->used && jp != nj && jp->state == JOBSTOPPED)
-			return (jp);
-	/* Otherwise the most recently used job that isn't `nj' */
-	for (jp = jobmru; jp != NULL; jp = jp->next)
-		if (jp->used && jp != nj)
-			return (jp);
-
-	return (NULL);
-}
-
-#endif
-
-/*
- * Fork of a subshell.  If we are doing job control, give the subshell its
- * own process group.  Jp is a job structure that the job is to be added to.
- * N is the command that will be evaluated by the child.  Both jp and n may
- * be NULL.  The mode parameter can be one of the following:
- *	FORK_FG - Fork off a foreground process.
- *	FORK_BG - Fork off a background process.
- *	FORK_NOJOB - Like FORK_FG, but don't give the process its own
- *		     process group even if job control is on.
- *
- * When job control is turned off, background processes have their standard
- * input redirected to /dev/null (except for the second and later processes
- * in a pipeline).
- */
-
-pid_t
-forkshell(struct job *jp, union node *n, int mode)
-{
-	pid_t pid;
-	pid_t pgrp;
-
-	TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n,
-	    mode));
-	INTOFF;
-	if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0))
-		checkzombies();
-	flushall();
-	pid = fork();
-	if (pid == -1) {
-		TRACE(("Fork failed, errno=%d\n", errno));
-		INTON;
-		error("Cannot fork: %s", strerror(errno));
-	}
-	if (pid == 0) {
-		struct job *p;
-		int wasroot;
-		int i;
-
-		TRACE(("Child shell %d\n", (int)getpid()));
-		wasroot = rootshell;
-		rootshell = 0;
-		handler = &main_handler;
-		closescript();
-		INTON;
-		forcelocal = 0;
-		clear_traps();
-#if JOBS
-		jobctl = 0;		/* do job control only in root shell */
-		if (wasroot && mode != FORK_NOJOB && mflag) {
-			if (jp == NULL || jp->nprocs == 0)
-				pgrp = getpid();
-			else
-				pgrp = jp->ps[0].pid;
-			if (setpgid(0, pgrp) == 0 && mode == FORK_FG &&
-			    ttyfd >= 0) {
-				/*** this causes superfluous TIOCSPGRPS ***/
-				if (tcsetpgrp(ttyfd, pgrp) < 0)
-					error("tcsetpgrp failed, errno=%d", errno);
-			}
-			setsignal(SIGTSTP);
-			setsignal(SIGTTOU);
-		} else if (mode == FORK_BG) {
-			ignoresig(SIGINT);
-			ignoresig(SIGQUIT);
-			if ((jp == NULL || jp->nprocs == 0) &&
-			    ! fd0_redirected_p ()) {
-				close(0);
-				if (open(_PATH_DEVNULL, O_RDONLY) != 0)
-					error("cannot open %s: %s",
-					    _PATH_DEVNULL, strerror(errno));
-			}
-		}
-#else
-		if (mode == FORK_BG) {
-			ignoresig(SIGINT);
-			ignoresig(SIGQUIT);
-			if ((jp == NULL || jp->nprocs == 0) &&
-			    ! fd0_redirected_p ()) {
-				close(0);
-				if (open(_PATH_DEVNULL, O_RDONLY) != 0)
-					error("cannot open %s: %s",
-					    _PATH_DEVNULL, strerror(errno));
-			}
-		}
-#endif
-		INTOFF;
-		for (i = njobs, p = jobtab ; --i >= 0 ; p++)
-			if (p->used)
-				freejob(p);
-		INTON;
-		if (wasroot && iflag) {
-			setsignal(SIGINT);
-			setsignal(SIGQUIT);
-			setsignal(SIGTERM);
-		}
-		return pid;
-	}
-	if (rootshell && mode != FORK_NOJOB && mflag) {
-		if (jp == NULL || jp->nprocs == 0)
-			pgrp = pid;
-		else
-			pgrp = jp->ps[0].pid;
-		setpgid(pid, pgrp);
-	}
-	if (mode == FORK_BG) {
-		if (bgjob != NULL && bgjob->state == JOBDONE &&
-		    !bgjob->remembered && !iflag)
-			freejob(bgjob);
-		backgndpid = pid;		/* set $! */
-		bgjob = jp;
-	}
-	if (jp) {
-		struct procstat *ps = &jp->ps[jp->nprocs++];
-		ps->pid = pid;
-		ps->status = -1;
-		ps->cmd = nullstr;
-		if (iflag && rootshell && n)
-			ps->cmd = commandtext(n);
-		jp->foreground = mode == FORK_FG;
-#if JOBS
-		setcurjob(jp);
-#endif
-	}
-	INTON;
-	TRACE(("In parent shell:  child = %d\n", (int)pid));
-	return pid;
-}
-
-
-pid_t
-vforkexecshell(struct job *jp, char **argv, char **envp, const char *path, int idx, int pip[2])
-{
-	pid_t pid;
-	struct jmploc jmploc;
-	struct jmploc *savehandler;
-
-	TRACE(("vforkexecshell(%%%td, %s, %p) called\n", jp - jobtab, argv[0],
-	    (void *)pip));
-	INTOFF;
-	flushall();
-	savehandler = handler;
-	pid = vfork();
-	if (pid == -1) {
-		TRACE(("Vfork failed, errno=%d\n", errno));
-		INTON;
-		error("Cannot fork: %s", strerror(errno));
-	}
-	if (pid == 0) {
-		TRACE(("Child shell %d\n", (int)getpid()));
-		if (setjmp(jmploc.loc))
-			_exit(exception == EXEXEC ? exerrno : 2);
-		if (pip != NULL) {
-			close(pip[0]);
-			if (pip[1] != 1) {
-				dup2(pip[1], 1);
-				close(pip[1]);
-			}
-		}
-		handler = &jmploc;
-		shellexec(argv, envp, path, idx);
-	}
-	handler = savehandler;
-	if (jp) {
-		struct procstat *ps = &jp->ps[jp->nprocs++];
-		ps->pid = pid;
-		ps->status = -1;
-		ps->cmd = nullstr;
-		jp->foreground = 1;
-#if JOBS
-		setcurjob(jp);
-#endif
-	}
-	INTON;
-	TRACE(("In parent shell:  child = %d\n", (int)pid));
-	return pid;
-}
-
-
-/*
- * Wait for job to finish.
- *
- * Under job control we have the problem that while a child process is
- * running interrupts generated by the user are sent to the child but not
- * to the shell.  This means that an infinite loop started by an inter-
- * active user may be hard to kill.  With job control turned off, an
- * interactive user may place an interactive program inside a loop.  If
- * the interactive program catches interrupts, the user doesn't want
- * these interrupts to also abort the loop.  The approach we take here
- * is to have the shell ignore interrupt signals while waiting for a
- * foreground process to terminate, and then send itself an interrupt
- * signal if the child process was terminated by an interrupt signal.
- * Unfortunately, some programs want to do a bit of cleanup and then
- * exit on interrupt; unless these processes terminate themselves by
- * sending a signal to themselves (instead of calling exit) they will
- * confuse this approach.
- */
-
-int
-waitforjob(struct job *jp, int *signaled)
-{
-#if JOBS
-	int propagate_int = jp->jobctl && jp->foreground;
-#endif
-	int status;
-	int st;
-
-	INTOFF;
-	TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1));
-	while (jp->state == 0)
-		if (dowait(DOWAIT_BLOCK | (Tflag ? DOWAIT_SIG |
-		    DOWAIT_SIG_TRAP : 0), jp) == -1)
-			dotrap();
-#if JOBS
-	if (jp->jobctl) {
-		if (ttyfd >= 0 && tcsetpgrp(ttyfd, rootpid) < 0)
-			error("tcsetpgrp failed, errno=%d\n", errno);
-	}
-	if (jp->state == JOBSTOPPED)
-		setcurjob(jp);
-#endif
-	status = getjobstatus(jp);
-	if (signaled != NULL)
-		*signaled = WIFSIGNALED(status);
-	/* convert to 8 bits */
-	if (WIFEXITED(status))
-		st = WEXITSTATUS(status);
-#if JOBS
-	else if (WIFSTOPPED(status))
-		st = WSTOPSIG(status) + 128;
-#endif
-	else
-		st = WTERMSIG(status) + 128;
-	if (! JOBS || jp->state == JOBDONE)
-		freejob(jp);
-	if (int_pending()) {
-		if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT)
-			CLEAR_PENDING_INT;
-	}
-#if JOBS
-	else if (rootshell && propagate_int &&
-			WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
-		kill(getpid(), SIGINT);
-#endif
-	INTON;
-	return st;
-}
-
-
-static void
-dummy_handler(int sig __unused)
-{
-}
-
-/*
- * Wait for a process to terminate.
- */
-
-static pid_t
-dowait(int mode, struct job *job)
-{
-	struct sigaction sa, osa;
-	sigset_t mask, omask;
-	pid_t pid;
-	int status;
-	struct procstat *sp;
-	struct job *jp;
-	struct job *thisjob;
-	const char *sigstr;
-	int done;
-	int stopped;
-	int sig;
-	int coredump;
-	int wflags;
-	int restore_sigchld;
-
-	TRACE(("dowait(%d, %p) called\n", mode, job));
-	restore_sigchld = 0;
-	if ((mode & DOWAIT_SIG) != 0) {
-		sigfillset(&mask);
-		sigprocmask(SIG_BLOCK, &mask, &omask);
-		INTOFF;
-		if (!issigchldtrapped()) {
-			restore_sigchld = 1;
-			sa.sa_handler = dummy_handler;
-			sa.sa_flags = 0;
-			sigemptyset(&sa.sa_mask);
-			sigaction(SIGCHLD, &sa, &osa);
-		}
-	}
-	do {
-#if JOBS
-		if (iflag)
-			wflags = WUNTRACED | WCONTINUED;
-		else
-#endif
-			wflags = 0;
-		if ((mode & (DOWAIT_BLOCK | DOWAIT_SIG)) != DOWAIT_BLOCK)
-			wflags |= WNOHANG;
-		pid = wait3(&status, wflags, (struct rusage *)NULL);
-		TRACE(("wait returns %d, status=%d\n", (int)pid, status));
-		if (pid == 0 && (mode & DOWAIT_SIG) != 0) {
-			pid = -1;
-			if (((mode & DOWAIT_SIG_TRAP) != 0 ?
-			    pendingsig : pendingsig_waitcmd) != 0) {
-				errno = EINTR;
-				break;
-			}
-			sigsuspend(&omask);
-			if (int_pending())
-				break;
-		}
-	} while (pid == -1 && errno == EINTR);
-	if (pid == -1 && errno == ECHILD && job != NULL)
-		job->state = JOBDONE;
-	if ((mode & DOWAIT_SIG) != 0) {
-		if (restore_sigchld)
-			sigaction(SIGCHLD, &osa, NULL);
-		sigprocmask(SIG_SETMASK, &omask, NULL);
-		INTON;
-	}
-	if (pid <= 0)
-		return pid;
-	INTOFF;
-	thisjob = NULL;
-	for (jp = jobtab ; jp < jobtab + njobs ; jp++) {
-		if (jp->used && jp->nprocs > 0) {
-			done = 1;
-			stopped = 1;
-			for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) {
-				if (sp->pid == -1)
-					continue;
-				if (sp->pid == pid && (sp->status == -1 ||
-				    WIFSTOPPED(sp->status))) {
-					TRACE(("Changing status of proc %d from 0x%x to 0x%x\n",
-						   (int)pid, sp->status,
-						   status));
-					if (WIFCONTINUED(status)) {
-						sp->status = -1;
-						jp->state = 0;
-					} else
-						sp->status = status;
-					thisjob = jp;
-				}
-				if (sp->status == -1)
-					stopped = 0;
-				else if (WIFSTOPPED(sp->status))
-					done = 0;
-			}
-			if (stopped) {		/* stopped or done */
-				int state = done? JOBDONE : JOBSTOPPED;
-				if (jp->state != state) {
-					TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state));
-					jp->state = state;
-					if (jp != job) {
-						if (done && !jp->remembered &&
-						    !iflag && jp != bgjob)
-							freejob(jp);
-#if JOBS
-						else if (done)
-							deljob(jp);
-#endif
-					}
-				}
-			}
-		}
-	}
-	INTON;
-	if (!thisjob || thisjob->state == 0)
-		;
-	else if ((!rootshell || !iflag || thisjob == job) &&
-	    thisjob->foreground && thisjob->state != JOBSTOPPED) {
-		sig = 0;
-		coredump = 0;
-		for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++)
-			if (WIFSIGNALED(sp->status)) {
-				sig = WTERMSIG(sp->status);
-				coredump = WCOREDUMP(sp->status);
-			}
-		if (sig > 0 && sig != SIGINT && sig != SIGPIPE) {
-			sigstr = strsignal(sig);
-			if (sigstr != NULL)
-				out2str(sigstr);
-			else
-				out2str("Unknown signal");
-			if (coredump)
-				out2str(" (core dumped)");
-			out2c('\n');
-			flushout(out2);
-		}
-	} else {
-		TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job));
-		thisjob->changed = 1;
-	}
-	return pid;
-}
-
-
-
-/*
- * return 1 if there are stopped jobs, otherwise 0
- */
-int job_warning = 0;
-int
-stoppedjobs(void)
-{
-	int jobno;
-	struct job *jp;
-
-	if (job_warning)
-		return (0);
-	for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) {
-		if (jp->used == 0)
-			continue;
-		if (jp->state == JOBSTOPPED) {
-			out2fmt_flush("You have stopped jobs.\n");
-			job_warning = 2;
-			return (1);
-		}
-	}
-
-	return (0);
-}
-
-
-static void
-checkzombies(void)
-{
-	while (njobs > 0 && dowait(0, NULL) > 0)
-		;
-}
-
-
-int
-backgndpidset(void)
-{
-	return backgndpid != -1;
-}
-
-
-pid_t
-backgndpidval(void)
-{
-	if (bgjob != NULL && !forcelocal)
-		bgjob->remembered = 1;
-	return backgndpid;
-}
-
-/*
- * Return a string identifying a command (to be printed by the
- * jobs command.
- */
-
-static char *cmdnextc;
-static int cmdnleft;
-#define MAXCMDTEXT	200
-
-char *
-commandtext(union node *n)
-{
-	char *name;
-
-	cmdnextc = name = ckmalloc(MAXCMDTEXT);
-	cmdnleft = MAXCMDTEXT - 4;
-	cmdtxt(n);
-	*cmdnextc = '\0';
-	return name;
-}
-
-
-static void
-cmdtxtdogroup(union node *n)
-{
-	cmdputs("; do ");
-	cmdtxt(n);
-	cmdputs("; done");
-}
-
-
-static void
-cmdtxtredir(union node *n, const char *op, int deffd)
-{
-	char s[2];
-
-	if (n->nfile.fd != deffd) {
-		s[0] = n->nfile.fd + '0';
-		s[1] = '\0';
-		cmdputs(s);
-	}
-	cmdputs(op);
-	if (n->type == NTOFD || n->type == NFROMFD) {
-		if (n->ndup.dupfd >= 0)
-			s[0] = n->ndup.dupfd + '0';
-		else
-			s[0] = '-';
-		s[1] = '\0';
-		cmdputs(s);
-	} else {
-		cmdtxt(n->nfile.fname);
-	}
-}
-
-
-static void
-cmdtxt(union node *n)
-{
-	union node *np;
-	struct nodelist *lp;
-
-	if (n == NULL)
-		return;
-	switch (n->type) {
-	case NSEMI:
-		cmdtxt(n->nbinary.ch1);
-		cmdputs("; ");
-		cmdtxt(n->nbinary.ch2);
-		break;
-	case NAND:
-		cmdtxt(n->nbinary.ch1);
-		cmdputs(" && ");
-		cmdtxt(n->nbinary.ch2);
-		break;
-	case NOR:
-		cmdtxt(n->nbinary.ch1);
-		cmdputs(" || ");
-		cmdtxt(n->nbinary.ch2);
-		break;
-	case NPIPE:
-		for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
-			cmdtxt(lp->n);
-			if (lp->next)
-				cmdputs(" | ");
-		}
-		break;
-	case NSUBSHELL:
-		cmdputs("(");
-		cmdtxt(n->nredir.n);
-		cmdputs(")");
-		break;
-	case NREDIR:
-	case NBACKGND:
-		cmdtxt(n->nredir.n);
-		break;
-	case NIF:
-		cmdputs("if ");
-		cmdtxt(n->nif.test);
-		cmdputs("; then ");
-		cmdtxt(n->nif.ifpart);
-		cmdputs("...");
-		break;
-	case NWHILE:
-		cmdputs("while ");
-		cmdtxt(n->nbinary.ch1);
-		cmdtxtdogroup(n->nbinary.ch2);
-		break;
-	case NUNTIL:
-		cmdputs("until ");
-		cmdtxt(n->nbinary.ch1);
-		cmdtxtdogroup(n->nbinary.ch2);
-		break;
-	case NFOR:
-		cmdputs("for ");
-		cmdputs(n->nfor.var);
-		cmdputs(" in ...");
-		break;
-	case NCASE:
-		cmdputs("case ");
-		cmdputs(n->ncase.expr->narg.text);
-		cmdputs(" in ...");
-		break;
-	case NDEFUN:
-		cmdputs(n->narg.text);
-		cmdputs("() ...");
-		break;
-	case NNOT:
-		cmdputs("! ");
-		cmdtxt(n->nnot.com);
-		break;
-	case NCMD:
-		for (np = n->ncmd.args ; np ; np = np->narg.next) {
-			cmdtxt(np);
-			if (np->narg.next)
-				cmdputs(" ");
-		}
-		for (np = n->ncmd.redirect ; np ; np = np->nfile.next) {
-			cmdputs(" ");
-			cmdtxt(np);
-		}
-		break;
-	case NARG:
-		cmdputs(n->narg.text);
-		break;
-	case NTO:
-		cmdtxtredir(n, ">", 1);
-		break;
-	case NAPPEND:
-		cmdtxtredir(n, ">>", 1);
-		break;
-	case NTOFD:
-		cmdtxtredir(n, ">&", 1);
-		break;
-	case NCLOBBER:
-		cmdtxtredir(n, ">|", 1);
-		break;
-	case NFROM:
-		cmdtxtredir(n, "<", 0);
-		break;
-	case NFROMTO:
-		cmdtxtredir(n, "<>", 0);
-		break;
-	case NFROMFD:
-		cmdtxtredir(n, "<&", 0);
-		break;
-	case NHERE:
-	case NXHERE:
-		cmdputs("<<...");
-		break;
-	default:
-		cmdputs("???");
-		break;
-	}
-}
-
-
-
-static void
-cmdputs(const char *s)
-{
-	const char *p;
-	char *q;
-	char c;
-	int subtype = 0;
-
-	if (cmdnleft <= 0)
-		return;
-	p = s;
-	q = cmdnextc;
-	while ((c = *p++) != '\0') {
-		if (c == CTLESC)
-			*q++ = *p++;
-		else if (c == CTLVAR) {
-			*q++ = '$';
-			if (--cmdnleft > 0)
-				*q++ = '{';
-			subtype = *p++;
-			if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0)
-				*q++ = '#';
-		} else if (c == '=' && subtype != 0) {
-			*q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL];
-			if (*q)
-				q++;
-			else
-				cmdnleft++;
-			if (((subtype & VSTYPE) == VSTRIMLEFTMAX ||
-			    (subtype & VSTYPE) == VSTRIMRIGHTMAX) &&
-			    --cmdnleft > 0)
-				*q = q[-1], q++;
-			subtype = 0;
-		} else if (c == CTLENDVAR) {
-			*q++ = '}';
-		} else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) {
-			cmdnleft -= 5;
-			if (cmdnleft > 0) {
-				*q++ = '$';
-				*q++ = '(';
-				*q++ = '.';
-				*q++ = '.';
-				*q++ = '.';
-				*q++ = ')';
-			}
-		} else if (c == CTLARI) {
-			cmdnleft -= 2;
-			if (cmdnleft > 0) {
-				*q++ = '$';
-				*q++ = '(';
-				*q++ = '(';
-			}
-			p++;
-		} else if (c == CTLENDARI) {
-			if (--cmdnleft > 0) {
-				*q++ = ')';
-				*q++ = ')';
-			}
-		} else if (c == CTLQUOTEMARK || c == CTLQUOTEEND)
-			cmdnleft++; /* ignore */
-		else
-			*q++ = c;
-		if (--cmdnleft <= 0) {
-			*q++ = '.';
-			*q++ = '.';
-			*q++ = '.';
-			break;
-		}
-	}
-	cmdnextc = q;
-}