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BSD 4_3 release
[unix-history] / usr / src / bin / csh / sh.proc.c
/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved. The Berkeley Software License Agreement
* specifies the terms and conditions for redistribution.
*/
#ifndef lint
static char *sccsid = "@(#)sh.proc.c 5.5 (Berkeley) 5/13/86";
#endif
#include "sh.h"
#include "sh.dir.h"
#include "sh.proc.h"
#include <sys/wait.h>
#include <sys/ioctl.h>
/*
* C Shell - functions that manage processes, handling hanging, termination
*/
#define BIGINDEX 9 /* largest desirable job index */
/*
* pchild - called at interrupt level by the SIGCHLD signal
* indicating that at least one child has terminated or stopped
* thus at least one wait system call will definitely return a
* childs status. Top level routines (like pwait) must be sure
* to mask interrupts when playing with the proclist data structures!
*/
pchild()
{
register struct process *pp;
register struct process *fp;
register int pid;
union wait w;
int jobflags;
struct rusage ru;
loop:
pid = wait3(&w, (setintr ? WNOHANG|WUNTRACED:WNOHANG), &ru);
if (pid <= 0) {
if (errno == EINTR) {
errno = 0;
goto loop;
}
pnoprocesses = pid == -1;
return;
}
for (pp = proclist.p_next; pp != PNULL; pp = pp->p_next)
if (pid == pp->p_pid)
goto found;
goto loop;
found:
if (pid == atoi(value("child")))
unsetv("child");
pp->p_flags &= ~(PRUNNING|PSTOPPED|PREPORTED);
if (WIFSTOPPED(w)) {
pp->p_flags |= PSTOPPED;
pp->p_reason = w.w_stopsig;
} else {
if (pp->p_flags & (PTIME|PPTIME) || adrof("time"))
(void) gettimeofday(&pp->p_etime, (struct timezone *)0);
pp->p_rusage = ru;
if (WIFSIGNALED(w)) {
if (w.w_termsig == SIGINT)
pp->p_flags |= PINTERRUPTED;
else
pp->p_flags |= PSIGNALED;
if (w.w_coredump)
pp->p_flags |= PDUMPED;
pp->p_reason = w.w_termsig;
} else {
pp->p_reason = w.w_retcode;
if (pp->p_reason != 0)
pp->p_flags |= PAEXITED;
else
pp->p_flags |= PNEXITED;
}
}
jobflags = 0;
fp = pp;
do {
if ((fp->p_flags & (PPTIME|PRUNNING|PSTOPPED)) == 0 &&
!child && adrof("time") &&
fp->p_rusage.ru_utime.tv_sec+fp->p_rusage.ru_stime.tv_sec >=
atoi(value("time")))
fp->p_flags |= PTIME;
jobflags |= fp->p_flags;
} while ((fp = fp->p_friends) != pp);
pp->p_flags &= ~PFOREGND;
if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
pp->p_flags &= ~PPTIME;
pp->p_flags |= PTIME;
}
if ((jobflags & (PRUNNING|PREPORTED)) == 0) {
fp = pp;
do {
if (fp->p_flags&PSTOPPED)
fp->p_flags |= PREPORTED;
} while((fp = fp->p_friends) != pp);
while(fp->p_pid != fp->p_jobid)
fp = fp->p_friends;
if (jobflags&PSTOPPED) {
if (pcurrent && pcurrent != fp)
pprevious = pcurrent;
pcurrent = fp;
} else
pclrcurr(fp);
if (jobflags&PFOREGND) {
if (jobflags & (PSIGNALED|PSTOPPED|PPTIME) ||
#ifdef IIASA
jobflags & PAEXITED ||
#endif
!eq(dcwd->di_name, fp->p_cwd->di_name)) {
; /* print in pjwait */
}
/*
else if ((jobflags & (PTIME|PSTOPPED)) == PTIME)
ptprint(fp);
*/
} else {
if (jobflags&PNOTIFY || adrof("notify")) {
printf("\215\n");
(void) pprint(pp, NUMBER|NAME|REASON);
if ((jobflags&PSTOPPED) == 0)
pflush(pp);
} else {
fp->p_flags |= PNEEDNOTE;
neednote++;
}
}
}
goto loop;
}
pnote()
{
register struct process *pp;
int flags, omask;
neednote = 0;
for (pp = proclist.p_next; pp != PNULL; pp = pp->p_next) {
if (pp->p_flags & PNEEDNOTE) {
omask = sigblock(sigmask(SIGCHLD));
pp->p_flags &= ~PNEEDNOTE;
flags = pprint(pp, NUMBER|NAME|REASON);
if ((flags&(PRUNNING|PSTOPPED)) == 0)
pflush(pp);
(void) sigsetmask(omask);
}
}
}
/*
* pwait - wait for current job to terminate, maintaining integrity
* of current and previous job indicators.
*/
pwait()
{
register struct process *fp, *pp;
int omask;
/*
* Here's where dead procs get flushed.
*/
omask = sigblock(sigmask(SIGCHLD));
for (pp = (fp = &proclist)->p_next; pp != PNULL; pp = (fp = pp)->p_next)
if (pp->p_pid == 0) {
fp->p_next = pp->p_next;
xfree(pp->p_command);
if (pp->p_cwd && --pp->p_cwd->di_count == 0)
if (pp->p_cwd->di_next == 0)
dfree(pp->p_cwd);
xfree((char *)pp);
pp = fp;
}
(void) sigsetmask(omask);
pjwait(pcurrjob);
}
/*
* pjwait - wait for a job to finish or become stopped
* It is assumed to be in the foreground state (PFOREGND)
*/
pjwait(pp)
register struct process *pp;
{
register struct process *fp;
int jobflags, reason, omask;
while (pp->p_pid != pp->p_jobid)
pp = pp->p_friends;
fp = pp;
do {
if ((fp->p_flags&(PFOREGND|PRUNNING)) == PRUNNING)
printf("BUG: waiting for background job!\n");
} while ((fp = fp->p_friends) != pp);
/*
* Now keep pausing as long as we are not interrupted (SIGINT),
* and the target process, or any of its friends, are running
*/
fp = pp;
omask = sigblock(sigmask(SIGCHLD));
for (;;) {
jobflags = 0;
do
jobflags |= fp->p_flags;
while ((fp = (fp->p_friends)) != pp);
if ((jobflags & PRUNNING) == 0)
break;
sigpause(sigblock(0) &~ sigmask(SIGCHLD));
}
(void) sigsetmask(omask);
if (tpgrp > 0) /* get tty back */
(void) ioctl(FSHTTY, TIOCSPGRP, (char *)&tpgrp);
if ((jobflags&(PSIGNALED|PSTOPPED|PTIME)) ||
!eq(dcwd->di_name, fp->p_cwd->di_name)) {
if (jobflags&PSTOPPED)
printf("\n");
(void) pprint(pp, AREASON|SHELLDIR);
}
if ((jobflags&(PINTERRUPTED|PSTOPPED)) && setintr &&
(!gointr || !eq(gointr, "-"))) {
if ((jobflags & PSTOPPED) == 0)
pflush(pp);
pintr1(0);
/*NOTREACHED*/
}
reason = 0;
fp = pp;
do {
if (fp->p_reason)
reason = fp->p_flags & (PSIGNALED|PINTERRUPTED) ?
fp->p_reason | QUOTE : fp->p_reason;
} while ((fp = fp->p_friends) != pp);
set("status", putn(reason));
if (reason && exiterr)
exitstat();
pflush(pp);
}
/*
* dowait - wait for all processes to finish
*/
dowait()
{
register struct process *pp;
int omask;
pjobs++;
omask = sigblock(sigmask(SIGCHLD));
loop:
for (pp = proclist.p_next; pp; pp = pp->p_next)
if (pp->p_pid && /* pp->p_pid == pp->p_jobid && */
pp->p_flags&PRUNNING) {
sigpause(0);
goto loop;
}
(void) sigsetmask(omask);
pjobs = 0;
}
/*
* pflushall - flush all jobs from list (e.g. at fork())
*/
pflushall()
{
register struct process *pp;
for (pp = proclist.p_next; pp != PNULL; pp = pp->p_next)
if (pp->p_pid)
pflush(pp);
}
/*
* pflush - flag all process structures in the same job as the
* the argument process for deletion. The actual free of the
* space is not done here since pflush is called at interrupt level.
*/
pflush(pp)
register struct process *pp;
{
register struct process *np;
register int index;
if (pp->p_pid == 0) {
printf("BUG: process flushed twice");
return;
}
while (pp->p_pid != pp->p_jobid)
pp = pp->p_friends;
pclrcurr(pp);
if (pp == pcurrjob)
pcurrjob = 0;
index = pp->p_index;
np = pp;
do {
np->p_index = np->p_pid = 0;
np->p_flags &= ~PNEEDNOTE;
} while ((np = np->p_friends) != pp);
if (index == pmaxindex) {
for (np = proclist.p_next, index = 0; np; np = np->p_next)
if (np->p_index > index)
index = np->p_index;
pmaxindex = index;
}
}
/*
* pclrcurr - make sure the given job is not the current or previous job;
* pp MUST be the job leader
*/
pclrcurr(pp)
register struct process *pp;
{
if (pp == pcurrent)
if (pprevious != PNULL) {
pcurrent = pprevious;
pprevious = pgetcurr(pp);
} else {
pcurrent = pgetcurr(pp);
pprevious = pgetcurr(pp);
}
else if (pp == pprevious)
pprevious = pgetcurr(pp);
}
/* +4 here is 1 for '\0', 1 ea for << >& >> */
char command[PMAXLEN+4];
int cmdlen;
char *cmdp;
/*
* palloc - allocate a process structure and fill it up.
* an important assumption is made that the process is running.
*/
palloc(pid, t)
int pid;
register struct command *t;
{
register struct process *pp;
int i;
pp = (struct process *)calloc(1, sizeof(struct process));
pp->p_pid = pid;
pp->p_flags = t->t_dflg & FAND ? PRUNNING : PRUNNING|PFOREGND;
if (t->t_dflg & FTIME)
pp->p_flags |= PPTIME;
cmdp = command;
cmdlen = 0;
padd(t);
*cmdp++ = 0;
if (t->t_dflg & FPOU) {
pp->p_flags |= PPOU;
if (t->t_dflg & FDIAG)
pp->p_flags |= PDIAG;
}
pp->p_command = savestr(command);
if (pcurrjob) {
struct process *fp;
/* careful here with interrupt level */
pp->p_cwd = 0;
pp->p_index = pcurrjob->p_index;
pp->p_friends = pcurrjob;
pp->p_jobid = pcurrjob->p_pid;
for (fp = pcurrjob; fp->p_friends != pcurrjob; fp = fp->p_friends)
;
fp->p_friends = pp;
} else {
pcurrjob = pp;
pp->p_jobid = pid;
pp->p_friends = pp;
pp->p_cwd = dcwd;
dcwd->di_count++;
if (pmaxindex < BIGINDEX)
pp->p_index = ++pmaxindex;
else {
struct process *np;
for (i = 1; ; i++) {
for (np = proclist.p_next; np; np = np->p_next)
if (np->p_index == i)
goto tryagain;
pp->p_index = i;
if (i > pmaxindex)
pmaxindex = i;
break;
tryagain:;
}
}
if (pcurrent == PNULL)
pcurrent = pp;
else if (pprevious == PNULL)
pprevious = pp;
}
pp->p_next = proclist.p_next;
proclist.p_next = pp;
(void) gettimeofday(&pp->p_btime, (struct timezone *)0);
}
padd(t)
register struct command *t;
{
char **argp;
if (t == 0)
return;
switch (t->t_dtyp) {
case TPAR:
pads("( ");
padd(t->t_dspr);
pads(" )");
break;
case TCOM:
for (argp = t->t_dcom; *argp; argp++) {
pads(*argp);
if (argp[1])
pads(" ");
}
break;
case TOR:
case TAND:
case TFIL:
case TLST:
padd(t->t_dcar);
switch (t->t_dtyp) {
case TOR:
pads(" || ");
break;
case TAND:
pads(" && ");
break;
case TFIL:
pads(" | ");
break;
case TLST:
pads("; ");
break;
}
padd(t->t_dcdr);
return;
}
if ((t->t_dflg & FPIN) == 0 && t->t_dlef) {
pads((t->t_dflg & FHERE) ? " << " : " < ");
pads(t->t_dlef);
}
if ((t->t_dflg & FPOU) == 0 && t->t_drit) {
pads((t->t_dflg & FCAT) ? " >>" : " >");
if (t->t_dflg & FDIAG)
pads("&");
pads(" ");
pads(t->t_drit);
}
}
pads(cp)
char *cp;
{
register int i = strlen(cp);
if (cmdlen >= PMAXLEN)
return;
if (cmdlen + i >= PMAXLEN) {
(void) strcpy(cmdp, " ...");
cmdlen = PMAXLEN;
cmdp += 4;
return;
}
(void) strcpy(cmdp, cp);
cmdp += i;
cmdlen += i;
}
/*
* psavejob - temporarily save the current job on a one level stack
* so another job can be created. Used for { } in exp6
* and `` in globbing.
*/
psavejob()
{
pholdjob = pcurrjob;
pcurrjob = PNULL;
}
/*
* prestjob - opposite of psavejob. This may be missed if we are interrupted
* somewhere, but pendjob cleans up anyway.
*/
prestjob()
{
pcurrjob = pholdjob;
pholdjob = PNULL;
}
/*
* pendjob - indicate that a job (set of commands) has been completed
* or is about to begin.
*/
pendjob()
{
register struct process *pp, *tp;
if (pcurrjob && (pcurrjob->p_flags&(PFOREGND|PSTOPPED)) == 0) {
pp = pcurrjob;
while (pp->p_pid != pp->p_jobid)
pp = pp->p_friends;
printf("[%d]", pp->p_index);
tp = pp;
do {
printf(" %d", pp->p_pid);
pp = pp->p_friends;
} while (pp != tp);
printf("\n");
}
pholdjob = pcurrjob = 0;
}
/*
* pprint - print a job
*/
pprint(pp, flag)
register struct process *pp;
{
register status, reason;
struct process *tp;
extern char *linp, linbuf[];
int jobflags, pstatus;
char *format;
while (pp->p_pid != pp->p_jobid)
pp = pp->p_friends;
if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
pp->p_flags &= ~PPTIME;
pp->p_flags |= PTIME;
}
tp = pp;
status = reason = -1;
jobflags = 0;
do {
jobflags |= pp->p_flags;
pstatus = pp->p_flags & PALLSTATES;
if (tp != pp && linp != linbuf && !(flag&FANCY) &&
(pstatus == status && pp->p_reason == reason ||
!(flag&REASON)))
printf(" ");
else {
if (tp != pp && linp != linbuf)
printf("\n");
if(flag&NUMBER)
if (pp == tp)
printf("[%d]%s %c ", pp->p_index,
pp->p_index < 10 ? " " : "",
pp==pcurrent ? '+' :
(pp == pprevious ? '-' : ' '));
else
printf(" ");
if (flag&FANCY)
printf("%5d ", pp->p_pid);
if (flag&(REASON|AREASON)) {
if (flag&NAME)
format = "%-21s";
else
format = "%s";
if (pstatus == status)
if (pp->p_reason == reason) {
printf(format, "");
goto prcomd;
} else
reason = pp->p_reason;
else {
status = pstatus;
reason = pp->p_reason;
}
switch (status) {
case PRUNNING:
printf(format, "Running ");
break;
case PINTERRUPTED:
case PSTOPPED:
case PSIGNALED:
if ((flag&(REASON|AREASON))
&& reason != SIGINT
&& reason != SIGPIPE)
printf(format, mesg[pp->p_reason].pname);
break;
case PNEXITED:
case PAEXITED:
if (flag & REASON)
if (pp->p_reason)
printf("Exit %-16d", pp->p_reason);
else
printf(format, "Done");
break;
default:
printf("BUG: status=%-9o", status);
}
}
}
prcomd:
if (flag&NAME) {
printf("%s", pp->p_command);
if (pp->p_flags & PPOU)
printf(" |");
if (pp->p_flags & PDIAG)
printf("&");
}
if (flag&(REASON|AREASON) && pp->p_flags&PDUMPED)
printf(" (core dumped)");
if (tp == pp->p_friends) {
if (flag&AMPERSAND)
printf(" &");
if (flag&JOBDIR &&
!eq(tp->p_cwd->di_name, dcwd->di_name)) {
printf(" (wd: ");
dtildepr(value("home"), tp->p_cwd->di_name);
printf(")");
}
}
if (pp->p_flags&PPTIME && !(status&(PSTOPPED|PRUNNING))) {
if (linp != linbuf)
printf("\n\t");
{ static struct rusage zru;
prusage(&zru, &pp->p_rusage, &pp->p_etime,
&pp->p_btime);
}
}
if (tp == pp->p_friends) {
if (linp != linbuf)
printf("\n");
if (flag&SHELLDIR && !eq(tp->p_cwd->di_name, dcwd->di_name)) {
printf("(wd now: ");
dtildepr(value("home"), dcwd->di_name);
printf(")\n");
}
}
} while ((pp = pp->p_friends) != tp);
if (jobflags&PTIME && (jobflags&(PSTOPPED|PRUNNING)) == 0) {
if (jobflags & NUMBER)
printf(" ");
ptprint(tp);
}
return (jobflags);
}
ptprint(tp)
register struct process *tp;
{
struct timeval tetime, diff;
static struct timeval ztime;
struct rusage ru;
static struct rusage zru;
register struct process *pp = tp;
ru = zru;
tetime = ztime;
do {
ruadd(&ru, &pp->p_rusage);
tvsub(&diff, &pp->p_etime, &pp->p_btime);
if (timercmp(&diff, &tetime, >))
tetime = diff;
} while ((pp = pp->p_friends) != tp);
prusage(&zru, &ru, &tetime, &ztime);
}
/*
* dojobs - print all jobs
*/
dojobs(v)
char **v;
{
register struct process *pp;
register int flag = NUMBER|NAME|REASON;
int i;
if (chkstop)
chkstop = 2;
if (*++v) {
if (v[1] || !eq(*v, "-l"))
error("Usage: jobs [ -l ]");
flag |= FANCY|JOBDIR;
}
for (i = 1; i <= pmaxindex; i++)
for (pp = proclist.p_next; pp; pp = pp->p_next)
if (pp->p_index == i && pp->p_pid == pp->p_jobid) {
pp->p_flags &= ~PNEEDNOTE;
if (!(pprint(pp, flag) & (PRUNNING|PSTOPPED)))
pflush(pp);
break;
}
}
/*
* dofg - builtin - put the job into the foreground
*/
dofg(v)
char **v;
{
register struct process *pp;
okpcntl();
++v;
do {
pp = pfind(*v);
pstart(pp, 1);
pjwait(pp);
} while (*v && *++v);
}
/*
* %... - builtin - put the job into the foreground
*/
dofg1(v)
char **v;
{
register struct process *pp;
okpcntl();
pp = pfind(v[0]);
pstart(pp, 1);
pjwait(pp);
}
/*
* dobg - builtin - put the job into the background
*/
dobg(v)
char **v;
{
register struct process *pp;
okpcntl();
++v;
do {
pp = pfind(*v);
pstart(pp, 0);
} while (*v && *++v);
}
/*
* %... & - builtin - put the job into the background
*/
dobg1(v)
char **v;
{
register struct process *pp;
pp = pfind(v[0]);
pstart(pp, 0);
}
/*
* dostop - builtin - stop the job
*/
dostop(v)
char **v;
{
pkill(++v, SIGSTOP);
}
/*
* dokill - builtin - superset of kill (1)
*/
dokill(v)
char **v;
{
register int signum;
register char *name;
v++;
if (v[0] && v[0][0] == '-') {
if (v[0][1] == 'l') {
for (signum = 1; signum <= NSIG; signum++) {
if (name = mesg[signum].iname)
printf("%s ", name);
if (signum == 16)
putchar('\n');
}
putchar('\n');
return;
}
if (digit(v[0][1])) {
signum = atoi(v[0]+1);
if (signum < 0 || signum > NSIG)
bferr("Bad signal number");
} else {
name = &v[0][1];
for (signum = 1; signum <= NSIG; signum++)
if (mesg[signum].iname &&
eq(name, mesg[signum].iname))
goto gotsig;
setname(name);
bferr("Unknown signal; kill -l lists signals");
}
gotsig:
v++;
} else
signum = SIGTERM;
pkill(v, signum);
}
pkill(v, signum)
char **v;
int signum;
{
register struct process *pp, *np;
register int jobflags = 0;
int omask, pid, err = 0;
char *cp;
extern char *sys_errlist[];
omask = sigmask(SIGCHLD);
if (setintr)
omask |= sigmask(SIGINT);
omask = sigblock(omask) & ~omask;
while (*v) {
cp = globone(*v);
if (*cp == '%') {
np = pp = pfind(cp);
do
jobflags |= np->p_flags;
while ((np = np->p_friends) != pp);
switch (signum) {
case SIGSTOP:
case SIGTSTP:
case SIGTTIN:
case SIGTTOU:
if ((jobflags & PRUNNING) == 0) {
printf("%s: Already stopped\n", cp);
err++;
goto cont;
}
}
if (killpg(pp->p_jobid, signum) < 0) {
printf("%s: ", cp);
printf("%s\n", sys_errlist[errno]);
err++;
}
if (signum == SIGTERM || signum == SIGHUP)
(void) killpg(pp->p_jobid, SIGCONT);
} else if (!(digit(*cp) || *cp == '-'))
bferr("Arguments should be jobs or process id's");
else {
pid = atoi(cp);
if (kill(pid, signum) < 0) {
printf("%d: ", pid);
printf("%s\n", sys_errlist[errno]);
err++;
goto cont;
}
if (signum == SIGTERM || signum == SIGHUP)
(void) kill(pid, SIGCONT);
}
cont:
xfree(cp);
v++;
}
(void) sigsetmask(omask);
if (err)
error(NOSTR);
}
/*
* pstart - start the job in foreground/background
*/
pstart(pp, foregnd)
register struct process *pp;
int foregnd;
{
register struct process *np;
int omask, jobflags = 0;
omask = sigblock(sigmask(SIGCHLD));
np = pp;
do {
jobflags |= np->p_flags;
if (np->p_flags&(PRUNNING|PSTOPPED)) {
np->p_flags |= PRUNNING;
np->p_flags &= ~PSTOPPED;
if (foregnd)
np->p_flags |= PFOREGND;
else
np->p_flags &= ~PFOREGND;
}
} while((np = np->p_friends) != pp);
if (!foregnd)
pclrcurr(pp);
(void) pprint(pp, foregnd ? NAME|JOBDIR : NUMBER|NAME|AMPERSAND);
if (foregnd)
(void) ioctl(FSHTTY, TIOCSPGRP, (char *)&pp->p_jobid);
if (jobflags&PSTOPPED)
(void) killpg(pp->p_jobid, SIGCONT);
(void) sigsetmask(omask);
}
panystop(neednl)
{
register struct process *pp;
chkstop = 2;
for (pp = proclist.p_next; pp; pp = pp->p_next)
if (pp->p_flags & PSTOPPED)
error("\nThere are stopped jobs" + 1 - neednl);
}
struct process *
pfind(cp)
char *cp;
{
register struct process *pp, *np;
if (cp == 0 || cp[1] == 0 || eq(cp, "%%") || eq(cp, "%+")) {
if (pcurrent == PNULL)
bferr("No current job");
return (pcurrent);
}
if (eq(cp, "%-") || eq(cp, "%#")) {
if (pprevious == PNULL)
bferr("No previous job");
return (pprevious);
}
if (digit(cp[1])) {
int index = atoi(cp+1);
for (pp = proclist.p_next; pp; pp = pp->p_next)
if (pp->p_index == index && pp->p_pid == pp->p_jobid)
return (pp);
bferr("No such job");
}
np = PNULL;
for (pp = proclist.p_next; pp; pp = pp->p_next)
if (pp->p_pid == pp->p_jobid) {
if (cp[1] == '?') {
register char *dp;
for (dp = pp->p_command; *dp; dp++) {
if (*dp != cp[2])
continue;
if (prefix(cp+2, dp))
goto match;
}
} else if (prefix(cp+1, pp->p_command)) {
match:
if (np)
bferr("Ambiguous");
np = pp;
}
}
if (np)
return (np);
if (cp[1] == '?')
bferr("No job matches pattern");
else
bferr("No such job");
/*NOTREACHED*/
}
/*
* pgetcurr - find most recent job that is not pp, preferably stopped
*/
struct process *
pgetcurr(pp)
register struct process *pp;
{
register struct process *np;
register struct process *xp = PNULL;
for (np = proclist.p_next; np; np = np->p_next)
if (np != pcurrent && np != pp && np->p_pid &&
np->p_pid == np->p_jobid) {
if (np->p_flags & PSTOPPED)
return (np);
if (xp == PNULL)
xp = np;
}
return (xp);
}
/*
* donotify - flag the job so as to report termination asynchronously
*/
donotify(v)
char **v;
{
register struct process *pp;
pp = pfind(*++v);
pp->p_flags |= PNOTIFY;
}
/*
* Do the fork and whatever should be done in the child side that
* should not be done if we are not forking at all (like for simple builtin's)
* Also do everything that needs any signals fiddled with in the parent side
*
* Wanttty tells whether process and/or tty pgrps are to be manipulated:
* -1: leave tty alone; inherit pgrp from parent
* 0: already have tty; manipulate process pgrps only
* 1: want to claim tty; manipulate process and tty pgrps
* It is usually just the value of tpgrp.
*/
pfork(t, wanttty)
struct command *t; /* command we are forking for */
int wanttty;
{
register int pid;
bool ignint = 0;
int pgrp, omask;
/*
* A child will be uninterruptible only under very special
* conditions. Remember that the semantics of '&' is
* implemented by disconnecting the process from the tty so
* signals do not need to ignored just for '&'.
* Thus signals are set to default action for children unless:
* we have had an "onintr -" (then specifically ignored)
* we are not playing with signals (inherit action)
*/
if (setintr)
ignint = (tpgrp == -1 && (t->t_dflg&FINT))
|| (gointr && eq(gointr, "-"));
/*
* Hold SIGCHLD until we have the process installed in our table.
*/
omask = sigblock(sigmask(SIGCHLD));
while ((pid = fork()) < 0)
if (setintr == 0)
sleep(FORKSLEEP);
else {
(void) sigsetmask(omask);
error("No more processes");
}
if (pid == 0) {
settimes();
pgrp = pcurrjob ? pcurrjob->p_jobid : getpid();
pflushall();
pcurrjob = PNULL;
child++;
if (setintr) {
setintr = 0; /* until I think otherwise */
/*
* Children just get blown away on SIGINT, SIGQUIT
* unless "onintr -" seen.
*/
(void) signal(SIGINT, ignint ? SIG_IGN : SIG_DFL);
(void) signal(SIGQUIT, ignint ? SIG_IGN : SIG_DFL);
if (wanttty >= 0) {
/* make stoppable */
(void) signal(SIGTSTP, SIG_DFL);
(void) signal(SIGTTIN, SIG_DFL);
(void) signal(SIGTTOU, SIG_DFL);
}
(void) signal(SIGTERM, parterm);
} else if (tpgrp == -1 && (t->t_dflg&FINT)) {
(void) signal(SIGINT, SIG_IGN);
(void) signal(SIGQUIT, SIG_IGN);
}
if (wanttty > 0)
(void) ioctl(FSHTTY, TIOCSPGRP, (char *)&pgrp);
if (wanttty >= 0 && tpgrp >= 0)
(void) setpgrp(0, pgrp);
if (tpgrp > 0)
tpgrp = 0; /* gave tty away */
/*
* Nohup and nice apply only to TCOM's but it would be
* nice (?!?) if you could say "nohup (foo;bar)"
* Then the parser would have to know about nice/nohup/time
*/
if (t->t_dflg & FNOHUP)
(void) signal(SIGHUP, SIG_IGN);
if (t->t_dflg & FNICE)
(void) setpriority(PRIO_PROCESS, 0, t->t_nice);
} else {
palloc(pid, t);
(void) sigsetmask(omask);
}
return (pid);
}
okpcntl()
{
if (tpgrp == -1)
error("No job control in this shell");
if (tpgrp == 0)
error("No job control in subshells");
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.