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diff --git a/bin/sh/jobs.c b/bin/sh/jobs.c
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+/*-
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. 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
+static char sccsid[] = "@(#)jobs.c 8.1 (Berkeley) 5/31/93";
+#endif /* not lint */
+
+#include "shell.h"
+#if JOBS
+#include "sgtty.h"
+#undef CEOF /* syntax.h redefines this */
+#endif
+#include "main.h"
+#include "parser.h"
+#include "nodes.h"
+#include "jobs.h"
+#include "options.h"
+#include "trap.h"
+#include "signames.h"
+#include "syntax.h"
+#include "input.h"
+#include "output.h"
+#include "memalloc.h"
+#include "error.h"
+#include "mystring.h"
+#include <fcntl.h>
+#include <signal.h>
+#include <errno.h>
+#ifdef BSD
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#endif
+
+
+
+struct job *jobtab; /* array of jobs */
+int njobs; /* size of array */
+MKINIT short backgndpid = -1; /* pid of last background process */
+#if JOBS
+int initialpgrp; /* pgrp of shell on invocation */
+short curjob; /* current job */
+#endif
+
+#ifdef __STDC__
+STATIC void restartjob(struct job *);
+STATIC struct job *getjob(char *);
+STATIC void freejob(struct job *);
+STATIC int procrunning(int);
+STATIC int dowait(int, struct job *);
+STATIC int waitproc(int, int *);
+#else
+STATIC void restartjob();
+STATIC struct job *getjob();
+STATIC void freejob();
+STATIC int procrunning();
+STATIC int dowait();
+STATIC int waitproc();
+#endif
+
+
+
+/*
+ * Turn job control on and off.
+ *
+ * Note: This code assumes that the third arg to ioctl is a character
+ * pointer, which is true on Berkeley systems but not System V. Since
+ * System V doesn't have job control yet, this isn't a problem now.
+ */
+
+MKINIT int jobctl;
+
+void
+setjobctl(on) {
+#ifdef OLD_TTY_DRIVER
+ int ldisc;
+#endif
+
+ if (on == jobctl || rootshell == 0)
+ return;
+ if (on) {
+ do { /* while we are in the background */
+ if (ioctl(2, TIOCGPGRP, (char *)&initialpgrp) < 0) {
+ out2str("sh: can't access tty; job control turned off\n");
+ mflag = 0;
+ return;
+ }
+ if (initialpgrp == -1)
+ initialpgrp = getpgrp(0);
+ else if (initialpgrp != getpgrp(0)) {
+ killpg(initialpgrp, SIGTTIN);
+ continue;
+ }
+ } while (0);
+#ifdef OLD_TTY_DRIVER
+ if (ioctl(2, TIOCGETD, (char *)&ldisc) < 0 || ldisc != NTTYDISC) {
+ out2str("sh: need new tty driver to run job control; job control turned off\n");
+ mflag = 0;
+ return;
+ }
+#endif
+ setsignal(SIGTSTP);
+ setsignal(SIGTTOU);
+ setsignal(SIGTTIN);
+ setpgrp(0, rootpid);
+ ioctl(2, TIOCSPGRP, (char *)&rootpid);
+ } else { /* turning job control off */
+ setpgrp(0, initialpgrp);
+ ioctl(2, TIOCSPGRP, (char *)&initialpgrp);
+ setsignal(SIGTSTP);
+ setsignal(SIGTTOU);
+ setsignal(SIGTTIN);
+ }
+ jobctl = on;
+}
+
+
+#ifdef mkinit
+
+SHELLPROC {
+ backgndpid = -1;
+#if JOBS
+ jobctl = 0;
+#endif
+}
+
+#endif
+
+
+
+#if JOBS
+fgcmd(argc, argv) char **argv; {
+ struct job *jp;
+ int pgrp;
+ int status;
+
+ jp = getjob(argv[1]);
+ if (jp->jobctl == 0)
+ error("job not created under job control");
+ pgrp = jp->ps[0].pid;
+ ioctl(2, TIOCSPGRP, (char *)&pgrp);
+ restartjob(jp);
+ INTOFF;
+ status = waitforjob(jp);
+ INTON;
+ return status;
+}
+
+
+bgcmd(argc, argv) char **argv; {
+ struct job *jp;
+
+ do {
+ jp = getjob(*++argv);
+ if (jp->jobctl == 0)
+ error("job not created under job control");
+ restartjob(jp);
+ } while (--argc > 1);
+ return 0;
+}
+
+
+STATIC void
+restartjob(jp)
+ struct job *jp;
+ {
+ struct procstat *ps;
+ int i;
+
+ if (jp->state == JOBDONE)
+ return;
+ INTOFF;
+ killpg(jp->ps[0].pid, SIGCONT);
+ for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
+ if ((ps->status & 0377) == 0177) {
+ ps->status = -1;
+ jp->state = 0;
+ }
+ }
+ INTON;
+}
+#endif
+
+
+int
+jobscmd(argc, argv) char **argv; {
+ showjobs(0);
+ return 0;
+}
+
+
+/*
+ * 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(change) {
+ int jobno;
+ int procno;
+ int i;
+ struct job *jp;
+ struct procstat *ps;
+ int col;
+ char s[64];
+
+ TRACE(("showjobs(%d) called\n", change));
+ while (dowait(0, (struct job *)NULL) > 0);
+ 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;
+ procno = jp->nprocs;
+ for (ps = jp->ps ; ; ps++) { /* for each process */
+ if (ps == jp->ps)
+ fmtstr(s, 64, "[%d] %d ", jobno, ps->pid);
+ else
+ fmtstr(s, 64, " %d ", ps->pid);
+ out1str(s);
+ col = strlen(s);
+ s[0] = '\0';
+ if (ps->status == -1) {
+ /* don't print anything */
+ } else if ((ps->status & 0xFF) == 0) {
+ fmtstr(s, 64, "Exit %d", ps->status >> 8);
+ } else {
+ i = ps->status;
+#if JOBS
+ if ((i & 0xFF) == 0177)
+ i >>= 8;
+#endif
+ if ((i & 0x7F) <= MAXSIG && sigmesg[i & 0x7F])
+ scopy(sigmesg[i & 0x7F], s);
+ else
+ fmtstr(s, 64, "Signal %d", i & 0x7F);
+ if (i & 0x80)
+ strcat(s, " (core dumped)");
+ }
+ out1str(s);
+ col += strlen(s);
+ do {
+ out1c(' ');
+ col++;
+ } while (col < 30);
+ out1str(ps->cmd);
+ out1c('\n');
+ if (--procno <= 0)
+ break;
+ }
+ jp->changed = 0;
+ if (jp->state == JOBDONE) {
+ freejob(jp);
+ }
+ }
+}
+
+
+/*
+ * Mark a job structure as unused.
+ */
+
+STATIC void
+freejob(jp)
+ struct job *jp;
+ {
+ struct procstat *ps;
+ int i;
+
+ INTOFF;
+ 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
+ if (curjob == jp - jobtab + 1)
+ curjob = 0;
+#endif
+ INTON;
+}
+
+
+
+int
+waitcmd(argc, argv) char **argv; {
+ struct job *job;
+ int status;
+ struct job *jp;
+
+ if (argc > 1) {
+ job = getjob(argv[1]);
+ } else {
+ job = NULL;
+ }
+ for (;;) { /* loop until process terminated or stopped */
+ if (job != NULL) {
+ if (job->state) {
+ status = job->ps[job->nprocs - 1].status;
+ if ((status & 0xFF) == 0)
+ status = status >> 8 & 0xFF;
+#if JOBS
+ else if ((status & 0xFF) == 0177)
+ status = (status >> 8 & 0x7F) + 128;
+#endif
+ else
+ status = (status & 0x7F) + 128;
+ if (! iflag)
+ freejob(job);
+ return status;
+ }
+ } else {
+ for (jp = jobtab ; ; jp++) {
+ if (jp >= jobtab + njobs) { /* no running procs */
+ return 0;
+ }
+ if (jp->used && jp->state == 0)
+ break;
+ }
+ }
+ dowait(1, (struct job *)NULL);
+ }
+}
+
+
+
+jobidcmd(argc, argv) char **argv; {
+ struct job *jp;
+ int i;
+
+ jp = getjob(argv[1]);
+ for (i = 0 ; i < jp->nprocs ; ) {
+ out1fmt("%d", jp->ps[i].pid);
+ out1c(++i < jp->nprocs? ' ' : '\n');
+ }
+ return 0;
+}
+
+
+
+/*
+ * Convert a job name to a job structure.
+ */
+
+STATIC struct job *
+getjob(name)
+ char *name;
+ {
+ int jobno;
+ register struct job *jp;
+ int pid;
+ int i;
+
+ if (name == NULL) {
+#if JOBS
+currentjob:
+ if ((jobno = curjob) == 0 || jobtab[jobno - 1].used == 0)
+ error("No current job");
+ return &jobtab[jobno - 1];
+#else
+ error("No current job");
+#endif
+ } else 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[2] == '\0') {
+ goto currentjob;
+#endif
+ } else {
+ register struct job *found = NULL;
+ for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
+ if (jp->used && jp->nprocs > 0
+ && prefix(name + 1, jp->ps[0].cmd)) {
+ if (found)
+ error("%s: ambiguous", name);
+ found = jp;
+ }
+ }
+ if (found)
+ return found;
+ }
+ } else if (is_number(name)) {
+ pid = 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;
+ }
+ }
+ error("No such job: %s", name);
+}
+
+
+
+/*
+ * Return a new job structure,
+ */
+
+struct job *
+makejob(node, nprocs)
+ union node *node;
+ {
+ int i;
+ struct job *jp;
+
+ for (i = njobs, jp = jobtab ; ; jp++) {
+ if (--i < 0) {
+ INTOFF;
+ if (njobs == 0) {
+ jobtab = ckmalloc(4 * sizeof jobtab[0]);
+ } else {
+ jp = ckmalloc((njobs + 4) * sizeof jobtab[0]);
+ bcopy(jobtab, jp, njobs * sizeof jp[0]);
+ 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;
+#if JOBS
+ jp->jobctl = jobctl;
+#endif
+ if (nprocs > 1) {
+ jp->ps = ckmalloc(nprocs * sizeof (struct procstat));
+ } else {
+ jp->ps = &jp->ps0;
+ }
+ INTON;
+ TRACE(("makejob(0x%x, %d) returns %%%d\n", (int)node, nprocs, jp - jobtab + 1));
+ return jp;
+}
+
+
+/*
+ * 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).
+ */
+
+int
+forkshell(jp, n, mode)
+ union node *n;
+ struct job *jp;
+ {
+ int pid;
+ int pgrp;
+
+ TRACE(("forkshell(%%%d, 0x%x, %d) called\n", jp - jobtab, (int)n, mode));
+ INTOFF;
+ pid = fork();
+ if (pid == -1) {
+ TRACE(("Fork failed, errno=%d\n", errno));
+ INTON;
+ error("Cannot fork");
+ }
+ if (pid == 0) {
+ struct job *p;
+ int wasroot;
+ int i;
+
+ TRACE(("Child shell %d\n", getpid()));
+ wasroot = rootshell;
+ rootshell = 0;
+ for (i = njobs, p = jobtab ; --i >= 0 ; p++)
+ if (p->used)
+ freejob(p);
+ closescript();
+ INTON;
+ 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;
+ setpgrp(0, pgrp);
+ if (mode == FORK_FG) {
+ /*** this causes superfluous TIOCSPGRPS ***/
+ if (ioctl(2, TIOCSPGRP, (char *)&pgrp) < 0)
+ error("TIOCSPGRP failed, errno=%d\n", 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("/dev/null", O_RDONLY) != 0)
+ error("Can't open /dev/null");
+ }
+ }
+#else
+ if (mode == FORK_BG) {
+ ignoresig(SIGINT);
+ ignoresig(SIGQUIT);
+ if ((jp == NULL || jp->nprocs == 0) &&
+ ! fd0_redirected_p ()) {
+ close(0);
+ if (open("/dev/null", O_RDONLY) != 0)
+ error("Can't open /dev/null");
+ }
+ }
+#endif
+ 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;
+ setpgrp(pid, pgrp);
+ }
+ if (mode == FORK_BG)
+ backgndpid = pid; /* set $! */
+ 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);
+ }
+ INTON;
+ TRACE(("In parent shell: child = %d\n", 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
+ * forground 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(jp)
+ register struct job *jp;
+ {
+#if JOBS
+ int mypgrp = getpgrp(0);
+#endif
+ int status;
+ int st;
+
+ INTOFF;
+ TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1));
+ while (jp->state == 0) {
+ dowait(1, jp);
+ }
+#if JOBS
+ if (jp->jobctl) {
+ if (ioctl(2, TIOCSPGRP, (char *)&mypgrp) < 0)
+ error("TIOCSPGRP failed, errno=%d\n", errno);
+ }
+ if (jp->state == JOBSTOPPED)
+ curjob = jp - jobtab + 1;
+#endif
+ status = jp->ps[jp->nprocs - 1].status;
+ /* convert to 8 bits */
+ if ((status & 0xFF) == 0)
+ st = status >> 8 & 0xFF;
+#if JOBS
+ else if ((status & 0xFF) == 0177)
+ st = (status >> 8 & 0x7F) + 128;
+#endif
+ else
+ st = (status & 0x7F) + 128;
+ if (! JOBS || jp->state == JOBDONE)
+ freejob(jp);
+ CLEAR_PENDING_INT;
+ if ((status & 0x7F) == SIGINT)
+ kill(getpid(), SIGINT);
+ INTON;
+ return st;
+}
+
+
+
+/*
+ * Wait for a process to terminate.
+ */
+
+STATIC int
+dowait(block, job)
+ struct job *job;
+ {
+ int pid;
+ int status;
+ struct procstat *sp;
+ struct job *jp;
+ struct job *thisjob;
+ int done;
+ int stopped;
+ int core;
+
+ TRACE(("dowait(%d) called\n", block));
+ do {
+ pid = waitproc(block, &status);
+ TRACE(("wait returns %d, status=%d\n", pid, status));
+ } while (pid == -1 && errno == EINTR);
+ if (pid <= 0)
+ return pid;
+ INTOFF;
+ thisjob = NULL;
+ for (jp = jobtab ; jp < jobtab + njobs ; jp++) {
+ if (jp->used) {
+ done = 1;
+ stopped = 1;
+ for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) {
+ if (sp->pid == -1)
+ continue;
+ if (sp->pid == pid) {
+ TRACE(("Changin status of proc %d from 0x%x to 0x%x\n", pid, sp->status, status));
+ sp->status = status;
+ thisjob = jp;
+ }
+ if (sp->status == -1)
+ stopped = 0;
+ else if ((sp->status & 0377) == 0177)
+ done = 0;
+ }
+ if (stopped) { /* stopped or done */
+ int state = done? JOBDONE : JOBSTOPPED;
+ if (jp->state != state) {
+ TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state));
+ jp->state = state;
+#if JOBS
+ if (done && curjob == jp - jobtab + 1)
+ curjob = 0; /* no current job */
+#endif
+ }
+ }
+ }
+ }
+ INTON;
+ if (! rootshell || ! iflag || (job && thisjob == job)) {
+#if JOBS
+ if ((status & 0xFF) == 0177)
+ status >>= 8;
+#endif
+ core = status & 0x80;
+ status &= 0x7F;
+ if (status != 0 && status != SIGINT && status != SIGPIPE) {
+ if (thisjob != job)
+ outfmt(out2, "%d: ", pid);
+#if JOBS
+ if (status == SIGTSTP && rootshell && iflag)
+ outfmt(out2, "%%%d ", job - jobtab + 1);
+#endif
+ if (status <= MAXSIG && sigmesg[status])
+ out2str(sigmesg[status]);
+ else
+ outfmt(out2, "Signal %d", status);
+ if (core)
+ out2str(" - core dumped");
+ out2c('\n');
+ flushout(&errout);
+ } else {
+ TRACE(("Not printing status: status=%d\n", status));
+ }
+ } else {
+ TRACE(("Not printing status, rootshell=%d, job=0x%x\n", rootshell, job));
+ if (thisjob)
+ thisjob->changed = 1;
+ }
+ return pid;
+}
+
+
+
+/*
+ * Do a wait system call. If job control is compiled in, we accept
+ * stopped processes. If block is zero, we return a value of zero
+ * rather than blocking.
+ *
+ * System V doesn't have a non-blocking wait system call. It does
+ * have a SIGCLD signal that is sent to a process when one of it's
+ * children dies. The obvious way to use SIGCLD would be to install
+ * a handler for SIGCLD which simply bumped a counter when a SIGCLD
+ * was received, and have waitproc bump another counter when it got
+ * the status of a process. Waitproc would then know that a wait
+ * system call would not block if the two counters were different.
+ * This approach doesn't work because if a process has children that
+ * have not been waited for, System V will send it a SIGCLD when it
+ * installs a signal handler for SIGCLD. What this means is that when
+ * a child exits, the shell will be sent SIGCLD signals continuously
+ * until is runs out of stack space, unless it does a wait call before
+ * restoring the signal handler. The code below takes advantage of
+ * this (mis)feature by installing a signal handler for SIGCLD and
+ * then checking to see whether it was called. If there are any
+ * children to be waited for, it will be.
+ *
+ * If neither SYSV nor BSD is defined, we don't implement nonblocking
+ * waits at all. In this case, the user will not be informed when
+ * a background process until the next time she runs a real program
+ * (as opposed to running a builtin command or just typing return),
+ * and the jobs command may give out of date information.
+ */
+
+#ifdef SYSV
+STATIC int gotsigchild;
+
+STATIC int onsigchild() {
+ gotsigchild = 1;
+}
+#endif
+
+
+STATIC int
+waitproc(block, status)
+ int *status;
+ {
+#ifdef BSD
+ int flags;
+
+#if JOBS
+ flags = WUNTRACED;
+#else
+ flags = 0;
+#endif
+ if (block == 0)
+ flags |= WNOHANG;
+ return wait3(status, flags, (struct rusage *)NULL);
+#else
+#ifdef SYSV
+ int (*save)();
+
+ if (block == 0) {
+ gotsigchild = 0;
+ save = signal(SIGCLD, onsigchild);
+ signal(SIGCLD, save);
+ if (gotsigchild == 0)
+ return 0;
+ }
+ return wait(status);
+#else
+ if (block == 0)
+ return 0;
+ return wait(status);
+#endif
+#endif
+}
+
+/*
+ * return 1 if there are stopped jobs, otherwise 0
+ */
+int job_warning = 0;
+int
+stoppedjobs()
+{
+ register int jobno;
+ register 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) {
+ out2str("You have stopped jobs.\n");
+ job_warning = 2;
+ return (1);
+ }
+ }
+
+ return (0);
+}
+
+/*
+ * Return a string identifying a command (to be printed by the
+ * jobs command.
+ */
+
+STATIC char *cmdnextc;
+STATIC int cmdnleft;
+STATIC void cmdtxt(), cmdputs();
+#define MAXCMDTEXT 200
+
+char *
+commandtext(n)
+ union node *n;
+ {
+ char *name;
+
+ cmdnextc = name = ckmalloc(MAXCMDTEXT);
+ cmdnleft = MAXCMDTEXT - 4;
+ cmdtxt(n);
+ *cmdnextc = '\0';
+ return name;
+}
+
+
+STATIC void
+cmdtxt(n)
+ union node *n;
+ {
+ union node *np;
+ struct nodelist *lp;
+ char *p;
+ int i;
+ char s[2];
+
+ 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 ");
+ goto until;
+ case NUNTIL:
+ cmdputs("until ");
+until:
+ cmdtxt(n->nbinary.ch1);
+ cmdputs("; do ");
+ cmdtxt(n->nbinary.ch2);
+ cmdputs("; done");
+ 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 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:
+ p = ">"; i = 1; goto redir;
+ case NAPPEND:
+ p = ">>"; i = 1; goto redir;
+ case NTOFD:
+ p = ">&"; i = 1; goto redir;
+ case NFROM:
+ p = "<"; i = 0; goto redir;
+ case NFROMFD:
+ p = "<&"; i = 0; goto redir;
+redir:
+ if (n->nfile.fd != i) {
+ s[0] = n->nfile.fd + '0';
+ s[1] = '\0';
+ cmdputs(s);
+ }
+ cmdputs(p);
+ if (n->type == NTOFD || n->type == NFROMFD) {
+ s[0] = n->ndup.dupfd + '0';
+ s[1] = '\0';
+ cmdputs(s);
+ } else {
+ cmdtxt(n->nfile.fname);
+ }
+ break;
+ case NHERE:
+ case NXHERE:
+ cmdputs("<<...");
+ break;
+ default:
+ cmdputs("???");
+ break;
+ }
+}
+
+
+
+STATIC void
+cmdputs(s)
+ char *s;
+ {
+ register char *p, *q;
+ register 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++;
+ } else if (c == '=' && subtype != 0) {
+ *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL];
+ subtype = 0;
+ } else if (c == CTLENDVAR) {
+ *q++ = '}';
+ } else if (c == CTLBACKQ | c == CTLBACKQ+CTLQUOTE)
+ cmdnleft++; /* ignore it */
+ else
+ *q++ = c;
+ if (--cmdnleft <= 0) {
+ *q++ = '.';
+ *q++ = '.';
+ *q++ = '.';
+ break;
+ }
+ }
+ cmdnextc = q;
+}
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