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mirror of https://git.FreeBSD.org/src.git synced 2024-12-16 10:20:30 +00:00
freebsd/bin/sh/jobs.c
Martin Cracauer adce2a1b4b Fix child's SIGSTOP behaviour in scripts.
When a child is receiving SIGSTOP, eval continues with the next
command.  While that is correct for the interactive case (Control-Z
and you get the prompt back), it is wrong for a shellscript, which
just continues with the next command, never again waiting for the
stopped child.  Noted when childs from cronjobs were stopped, just to
make more processes (by wosch).

The fix is not to return from a job wait when the wait returned for a
stopped child while in non-interactive mode.  This bahaviour seems to
be what bash2 and ksh implement.  I tested for correct behaviour for
finnaly killing the child with and without forgrounding it first.
When not foregrouding before killing, the shell continues with the
script, which is what the other shells do as well.

Reviewed by:	Silence on -current
2001-02-06 10:29:34 +00:00

1159 lines
24 KiB
C

/*-
* 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
#if 0
static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <fcntl.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/param.h>
#ifdef BSD
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <paths.h>
#endif
#include <sys/ioctl.h>
#include "shell.h"
#if JOBS
#if OLD_TTY_DRIVER
#include "sgtty.h"
#else
#include <termios.h>
#endif
#undef CEOF /* syntax.h redefines this */
#endif
#include "redir.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"
struct job *jobtab; /* array of jobs */
int njobs; /* size of array */
MKINIT pid_t backgndpid = -1; /* pid of last background process */
#if JOBS
int initialpgrp; /* pgrp of shell on invocation */
int curjob; /* current job */
#endif
int in_waitcmd = 0; /* are we in waitcmd()? */
int in_dowait = 0; /* are we in dowait()? */
volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */
#if JOBS
STATIC void restartjob __P((struct job *));
#endif
STATIC void freejob __P((struct job *));
STATIC struct job *getjob __P((char *));
STATIC int dowait __P((int, struct job *));
#if SYSV
STATIC int onsigchild __P((void));
#endif
STATIC int waitproc __P((int, int *));
STATIC void cmdtxt __P((union node *));
STATIC void cmdputs __P((char *));
/*
* 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;
#if JOBS
void
setjobctl(on)
int on;
{
#ifdef OLD_TTY_DRIVER
int ldisc;
#endif
if (on == jobctl || rootshell == 0)
return;
if (on) {
do { /* while we are in the background */
#ifdef OLD_TTY_DRIVER
if (ioctl(2, TIOCGPGRP, (char *)&initialpgrp) < 0) {
#else
initialpgrp = tcgetpgrp(2);
if (initialpgrp < 0) {
#endif
out2str("sh: can't access tty; job control turned off\n");
mflag = 0;
return;
}
if (initialpgrp == -1)
initialpgrp = getpgrp();
else if (initialpgrp != getpgrp()) {
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);
setpgid(0, rootpid);
#ifdef OLD_TTY_DRIVER
ioctl(2, TIOCSPGRP, (char *)&rootpid);
#else
tcsetpgrp(2, rootpid);
#endif
} else { /* turning job control off */
setpgid(0, initialpgrp);
#ifdef OLD_TTY_DRIVER
ioctl(2, TIOCSPGRP, (char *)&initialpgrp);
#else
tcsetpgrp(2, initialpgrp);
#endif
setsignal(SIGTSTP);
setsignal(SIGTTOU);
setsignal(SIGTTIN);
}
jobctl = on;
}
#endif
#ifdef mkinit
INCLUDE <sys/types.h>
INCLUDE <stdlib.h>
SHELLPROC {
backgndpid = -1;
#if JOBS
jobctl = 0;
#endif
}
#endif
#if JOBS
int
fgcmd(argc, argv)
int argc __unused;
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;
#ifdef OLD_TTY_DRIVER
ioctl(2, TIOCSPGRP, (char *)&pgrp);
#else
tcsetpgrp(2, pgrp);
#endif
restartjob(jp);
INTOFF;
status = waitforjob(jp, (int *)NULL);
INTON;
return status;
}
int
bgcmd(argc, argv)
int argc;
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 (WIFSTOPPED(ps->status)) {
ps->status = -1;
jp->state = 0;
}
}
INTON;
}
#endif
int
jobscmd(argc, argv)
int argc __unused;
char **argv __unused;
{
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 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 (WIFEXITED(ps->status)) {
fmtstr(s, 64, "Exit %d", WEXITSTATUS(ps->status));
} else {
#if JOBS
if (WIFSTOPPED(ps->status))
i = WSTOPSIG(ps->status);
else
#endif
i = WTERMSIG(ps->status);
if ((i & 0x7F) < NSIG && sys_siglist[i & 0x7F])
scopy(sys_siglist[i & 0x7F], s);
else
fmtstr(s, 64, "Signal %d", i & 0x7F);
if (WCOREDUMP(ps->status))
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)
int argc;
char **argv;
{
struct job *job;
int status, retval;
struct job *jp;
if (argc > 1) {
job = getjob(argv[1]);
} else {
job = NULL;
}
/*
* Loop until a process is terminated or stopped, or a SIGINT is
* received.
*/
in_waitcmd++;
do {
if (job != NULL) {
if (job->state) {
status = job->ps[job->nprocs - 1].status;
if (WIFEXITED(status))
retval = WEXITSTATUS(status);
#if JOBS
else if (WIFSTOPPED(status))
retval = WSTOPSIG(status) + 128;
#endif
else
retval = WTERMSIG(status) + 128;
if (! iflag)
freejob(job);
in_waitcmd--;
return retval;
}
} else {
for (jp = jobtab ; ; jp++) {
if (jp >= jobtab + njobs) { /* no running procs */
in_waitcmd--;
return 0;
}
if (jp->used && jp->state == 0)
break;
}
}
} while (dowait(1, (struct job *)NULL) != -1);
in_waitcmd--;
return 0;
}
int
jobidcmd(argc, argv)
int argc __unused;
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;
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 {
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);
/*NOTREACHED*/
return NULL;
}
/*
* Return a new job structure,
*/
struct job *
makejob(node, nprocs)
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]);
} else {
jp = ckmalloc((njobs + 4) * sizeof jobtab[0]);
memcpy(jp, jobtab, njobs * sizeof jp[0]);
/* 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;
#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%lx, %d) returns %%%d\n", (long)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 mode;
{
int pid;
int pgrp;
TRACE(("forkshell(%%%d, 0x%lx, %d) called\n", jp - jobtab, (long)n,
mode));
INTOFF;
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", 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;
if (setpgid(0, pgrp) == 0 && mode == FORK_FG) {
/*** this causes superfluous TIOCSPGRPS ***/
#ifdef OLD_TTY_DRIVER
if (ioctl(2, TIOCSPGRP, (char *)&pgrp) < 0)
error("TIOCSPGRP failed, errno=%d", errno);
#else
if (tcsetpgrp(2, pgrp) < 0)
error("tcsetpgrp failed, errno=%d", errno);
#endif
}
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("Can't 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("Can't open %s: %s",
_PATH_DEVNULL, strerror(errno));
}
}
#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;
setpgid(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
* 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(jp, origstatus)
struct job *jp;
int *origstatus;
{
#if JOBS
int mypgrp = getpgrp();
#endif
int status;
int st;
INTOFF;
TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1));
while (jp->state == 0)
if (dowait(1, jp) == -1)
dotrap();
#if JOBS
if (jp->jobctl) {
#ifdef OLD_TTY_DRIVER
if (ioctl(2, TIOCSPGRP, (char *)&mypgrp) < 0)
error("TIOCSPGRP failed, errno=%d\n", errno);
#else
if (tcsetpgrp(2, mypgrp) < 0)
error("tcsetpgrp failed, errno=%d\n", errno);
#endif
}
if (jp->state == JOBSTOPPED)
curjob = jp - jobtab + 1;
#endif
status = jp->ps[jp->nprocs - 1].status;
if (origstatus != NULL)
*origstatus = 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)
kill(getpid(), SIGINT);
else
CLEAR_PENDING_INT;
}
INTON;
return st;
}
/*
* Wait for a process to terminate.
*/
STATIC int
dowait(block, job)
int block;
struct job *job;
{
int pid;
int status;
struct procstat *sp;
struct job *jp;
struct job *thisjob;
int done;
int stopped;
int core;
int sig;
in_dowait++;
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 && breakwaitcmd == 0) ||
(WIFSTOPPED(status) && !iflag));
in_dowait--;
if (breakwaitcmd != 0) {
breakwaitcmd = 0;
return -1;
}
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(("Changing 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 (WIFSTOPPED(sp->status))
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)) {
core = WCOREDUMP(status);
#if JOBS
if (WIFSTOPPED(status))
sig = WSTOPSIG(status);
else
#endif
if (WIFEXITED(status))
sig = 0;
else
sig = WTERMSIG(status);
if (sig != 0 && sig != SIGINT && sig != SIGPIPE) {
if (thisjob != job)
outfmt(out2, "%d: ", pid);
#if JOBS
if (sig == SIGTSTP && rootshell && iflag)
outfmt(out2, "%%%d ", job - jobtab + 1);
#endif
if (sig < NSIG && sys_siglist[sig])
out2str(sys_siglist[sig]);
else
outfmt(out2, "Signal %d", sig);
if (core)
out2str(" - core dumped");
out2c('\n');
flushout(&errout);
} else {
TRACE(("Not printing status: status=%d, sig=%d\n",
status, sig));
}
} 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 sig_atomic_t gotsigchild;
STATIC int onsigchild() {
gotsigchild = 1;
}
#endif
STATIC int
waitproc(block, status)
int block;
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()
{
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) {
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;
#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 NFROMTO:
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;
{
char *p, *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++;
} 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;
}