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freebsd-src/bin/sh/jobs.c
Jilles Tjoelker ed4c3b5f86 sh: Forget about terminated background processes sooner. 
Unless $! has been referenced for a particular job or $! still contains that
job's pid, forget about it after it has terminated. If $! has been
referenced, remember the job until the wait builtin has reported its
completion (either with the pid as parameter or without parameters).

In interactive mode, jobs are forgotten after termination has been reported,
which happens before primary prompts and through the jobs builtin. Even
then, though, remember a job if $! has been referenced.

This is similar to what is suggested by POSIX and should fix most memory
leaks (which also tend to cause sh to use more CPU time) with long running
scripts that start background jobs.

Caveats:
* Repeatedly referencing $! without ever doing 'wait', like
    while :; do foo & echo started foo: $!; sleep 60; done
  will still use a lot of memory and CPU time in the long run.
* The jobs and jobid builtins do not cause a job to be remembered for longer
  like expanding $! does.

PR:		bin/55346
2010-06-29 22:37:45 +00:00

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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.
* 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
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <fcntl.h>
#include <signal.h>
#include <errno.h>
#include <paths.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/param.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <paths.h>
#include <sys/ioctl.h>
#include "shell.h"
#if JOBS
#include <termios.h>
#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"
STATIC struct job *jobtab; /* array of jobs */
STATIC int njobs; /* size of array */
MKINIT pid_t backgndpid = -1; /* pid of last background process */
MKINIT 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
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? */
static int ttyfd = -1;
#if JOBS
STATIC void restartjob(struct job *);
#endif
STATIC void freejob(struct job *);
STATIC struct job *getjob(char *);
STATIC pid_t dowait(int, struct job *);
STATIC pid_t waitproc(int, int *);
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 void showjob(struct job *, pid_t, int);
/*
* Turn job control on and off.
*/
MKINIT int jobctl;
#if JOBS
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)) < 0) {
i = 0;
while (i <= 2 && !isatty(i))
i++;
if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0)
goto out;
}
if (ttyfd < 10) {
/*
* Keep our TTY file descriptor out of the way of
* the user's redirections.
*/
if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) {
close(ttyfd);
ttyfd = -1;
goto out;
}
close(ttyfd);
ttyfd = i;
}
if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) {
close(ttyfd);
ttyfd = -1;
goto out;
}
do { /* while we are in the background */
initialpgrp = tcgetpgrp(ttyfd);
if (initialpgrp < 0) {
out: out2fmt_flush("sh: can't access tty; job control turned off\n");
mflag = 0;
return;
}
if (initialpgrp == -1)
initialpgrp = getpgrp();
else if (initialpgrp != getpgrp()) {
killpg(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);
tcsetpgrp(ttyfd, initialpgrp);
close(ttyfd);
ttyfd = -1;
setsignal(SIGTSTP);
setsignal(SIGTTOU);
setsignal(SIGTTIN);
}
jobctl = on;
}
#endif
#ifdef mkinit
INCLUDE <sys/types.h>
INCLUDE <stdlib.h>
SHELLPROC {
backgndpid = -1;
bgjob = NULL;
#if JOBS
jobctl = 0;
#endif
}
#endif
#if JOBS
int
fgcmd(int argc __unused, char **argv)
{
struct job *jp;
pid_t pgrp;
int status;
jp = getjob(argv[1]);
if (jp->jobctl == 0)
error("job not created under job control");
out1str(jp->ps[0].cmd);
out1c('\n');
flushout(&output);
pgrp = jp->ps[0].pid;
tcsetpgrp(ttyfd, pgrp);
restartjob(jp);
jp->foreground = 1;
INTOFF;
status = waitforjob(jp, (int *)NULL);
INTON;
return status;
}
int
bgcmd(int argc, char **argv)
{
char s[64];
struct job *jp;
do {
jp = getjob(*++argv);
if (jp->jobctl == 0)
error("job not created under job control");
if (jp->state == JOBDONE)
continue;
restartjob(jp);
jp->foreground = 0;
fmtstr(s, 64, "[%td] ", jp - jobtab + 1);
out1str(s);
out1str(jp->ps[0].cmd);
out1c('\n');
} while (--argc > 1);
return 0;
}
STATIC void
restartjob(struct job *jp)
{
struct procstat *ps;
int i;
if (jp->state == JOBDONE)
return;
setcurjob(jp);
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(int argc, char *argv[])
{
char *id;
int ch, mode;
optind = optreset = 1;
opterr = 0;
mode = SHOWJOBS_DEFAULT;
while ((ch = getopt(argc, argv, "lps")) != -1) {
switch (ch) {
case 'l':
mode = SHOWJOBS_VERBOSE;
break;
case 'p':
mode = SHOWJOBS_PGIDS;
break;
case 's':
mode = SHOWJOBS_PIDS;
break;
case '?':
default:
error("unknown option: -%c", optopt);
}
}
argc -= optind;
argv += optind;
if (argc == 0)
showjobs(0, mode);
else
while ((id = *argv++) != NULL)
showjob(getjob(id), 0, mode);
return (0);
}
STATIC void
showjob(struct job *jp, pid_t pid, int mode)
{
char s[64];
struct procstat *ps;
struct job *j;
int col, curr, i, jobno, prev, procno;
pid_t ppid;
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
for (ps = jp->ps ; ; ps++) { /* for each process */
if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) {
ppid = (mode == SHOWJOBS_PIDS) ? ps->pid :
getpgid(ps->pid);
out1fmt("%d\n", (int)ppid);
goto skip;
}
if (mode != SHOWJOBS_VERBOSE && ps != jp->ps && pid == 0)
goto skip;
if (pid != 0 && pid != ps->pid)
goto skip;
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);
}
s[0] = '\0';
if (ps != jp->ps) {
*s = '\0';
} else if (ps->status == -1) {
strcpy(s, "Running");
} else if (WIFEXITED(ps->status)) {
if (WEXITSTATUS(ps->status) == 0)
strcpy(s, "Done");
else
fmtstr(s, 64, "Done (%d)",
WEXITSTATUS(ps->status));
} else {
#if JOBS
if (WIFSTOPPED(ps->status))
i = WSTOPSIG(ps->status);
else
#endif
i = WTERMSIG(ps->status);
if ((i & 0x7F) < sys_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');
skip: if (--procno <= 0)
break;
}
}
/*
* 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, 0, mode);
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, 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 || ! job->changed)
freejob(job);
else {
job->remembered = 0;
if (job == bgjob)
bgjob = NULL;
}
in_waitcmd--;
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 */
in_waitcmd--;
return 0;
}
if (jp->used && jp->state == 0)
break;
}
}
} while (dowait(1, (struct job *)NULL) != -1);
in_waitcmd--;
return 0;
}
int
jobidcmd(int argc __unused, char **argv)
{
struct job *jp;
int i;
jp = getjob(argv[1]);
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(char *name)
{
int jobno;
struct job *found, *jp;
pid_t pid;
int i;
if (name == NULL) {
#if JOBS
currentjob: if ((jp = getcurjob(NULL)) == NULL)
error("No current job");
return (jp);
#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;
} else if (name[1] == '+' && name[2] == '\0') {
goto currentjob;
} 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 {
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 = (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;
}
}
error("No such job: %s", name);
/*NOTREACHED*/
return NULL;
}
/*
* 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;
#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 %%%d\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(%%%d, %p, %d) called\n", jp - jobtab, (void *)n,
mode));
INTOFF;
if (mode == FORK_BG)
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;
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 ***/
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("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
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;
}
/*
* 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 *origstatus)
{
#if JOBS
pid_t mypgrp = getpgrp();
int propagate_int = jp->jobctl && jp->foreground;
#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) {
if (tcsetpgrp(ttyfd, mypgrp) < 0)
error("tcsetpgrp failed, errno=%d\n", errno);
}
if (jp->state == JOBSTOPPED)
setcurjob(jp);
#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;
}
#if JOBS
else if (rootshell && iflag && propagate_int &&
WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
kill(getpid(), SIGINT);
#endif
INTON;
return st;
}
/*
* Wait for a process to terminate.
*/
STATIC pid_t
dowait(int block, struct job *job)
{
pid_t pid;
int status;
struct procstat *sp;
struct job *jp;
struct job *thisjob;
int done;
int stopped;
int sig;
int i;
in_dowait++;
TRACE(("dowait(%d) called\n", block));
do {
pid = waitproc(block, &status);
TRACE(("wait returns %d, status=%d\n", (int)pid, status));
} while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) ||
(pid > 0 && WIFSTOPPED(status) && !iflag));
in_dowait--;
if (pid == -1 && errno == ECHILD && job != NULL)
job->state = JOBDONE;
if (breakwaitcmd != 0) {
breakwaitcmd = 0;
if (pid <= 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",
(int)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 (jp != job) {
if (done && !jp->remembered &&
!iflag && jp != bgjob)
freejob(jp);
#if JOBS
else if (done)
deljob(jp);
#endif
}
}
}
}
}
INTON;
if (! rootshell || ! iflag || (job && thisjob == job)) {
#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 (!mflag ||
(thisjob->foreground && !WIFSTOPPED(status))) {
i = WTERMSIG(status);
if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F])
out1str(sys_siglist[i & 0x7F]);
else
out1fmt("Signal %d", i & 0x7F);
if (WCOREDUMP(status))
out1str(" (core dumped)");
out1c('\n');
} else
showjob(thisjob, pid, SHOWJOBS_DEFAULT);
}
} else {
TRACE(("Not printing status, rootshell=%d, job=%p\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.
*/
STATIC pid_t
waitproc(int block, int *status)
{
int flags;
#if JOBS
flags = WUNTRACED;
#else
flags = 0;
#endif
if (block == 0)
flags |= WNOHANG;
return wait3(status, flags, (struct rusage *)NULL);
}
/*
* 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)
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
cmdtxt(union node *n)
{
union node *np;
struct nodelist *lp;
const 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 NCLOBBER:
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) {
if (n->ndup.dupfd >= 0)
s[0] = n->ndup.dupfd + '0';
else
s[0] = '-';
s[1] = '\0';
cmdputs(s);
} else {
cmdtxt(n->nfile.fname);
}
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++;
} 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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