sh.proc.c

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· C语言 代码 · 共 1,167 行 · 第 1/2 页

	if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
		pp->p_flags &= ~PPTIME;
		pp->p_flags |= PTIME;
	}
	tp = pp;
	status = reason = -1; 
	jobflags = 0;

	/*
	 Ring terminal bell, if requested.
	 Characters must be quoted to keep from
	 being echoed as ^x
	*/
	if (flag&NOISEOK && adrof("notify"))
	    {
	    register unsigned char *nmp;

	    for (nmp = (unsigned char *)value("notify"); *nmp; nmp++)
		{
		if (*nmp == QUOTECHAR)	/* simply skip all quote chars */
			nmp++;
		putchar((int)(QUOTE|*nmp));
	        }
	    }

	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)))
			csh_printf(" ");			/* 004 RNF */
		else {
			if (tp != pp && linp != linbuf)
				csh_printf("\n");		/* 004 RNF */
			if(flag&NUMBER)
				if (pp == tp)
			/* 004 RNF */	csh_printf("[%d]%s %c ", pp->p_index,
					    pp->p_index < 10 ? " " : "",
					    pp==pcurrent ? '+' :
						(pp == pprevious ? '-' : ' '));
				else
					csh_printf("       ");	/* 004 RNF */
			if (flag&FANCY)
				csh_printf("%5d ", pp->p_pid);	/* 004 RNF */
			if (flag&(REASON|AREASON)) {
				if (flag&NAME)
					format = "%-21s";
				else
					format = "%s";
				if (pstatus == status)
					if (pp->p_reason == reason) {
						csh_printf(format, ""); /* 004 RNF */
						goto prcomd;
					} else
						reason = pp->p_reason;
				else {
					status = pstatus;
					reason = pp->p_reason;
				}
				switch (status) {

				case PRUNNING:
					csh_printf(format, "Running "); /* 004 RNF */
					break;

				case PINTERRUPTED:
				case PSTOPPED:
				case PSIGNALED:
					if ((flag&(REASON|AREASON))
					    && reason != SIGINT
					    && reason != SIGPIPE)
						csh_printf(format, mesg[pp->p_reason].pname); /* 004 RNF */
					break;

				case PNEXITED:
				case PAEXITED:
					if (flag & REASON)
						if (pp->p_reason)
							csh_printf("Exit %-16d", pp->p_reason); /* 004 RNF */
						else
							csh_printf(format, "Done"); /* 004 RNF */
					break;

				default:
					csh_printf("BUG: status=%-9o", status); /* 004 RNF */
				}
			}
		}
prcomd:
		if (flag&NAME) {
			csh_printf("%s", pp->p_command); 	/* 004 RNF */
			if (pp->p_flags & PPOU)
				csh_printf(" |");		/* 004 RNF */
			if (pp->p_flags & PDIAG)
				csh_printf("&");		/* 004 RNF */
		}
		if (flag&(REASON|AREASON) && pp->p_flags&PDUMPED)
			csh_printf(" (core dumped)");		/* 004 RNF */
		if (tp == pp->p_friends) {
			if (flag&AMPERSAND)
				csh_printf(" &");		/* 004 RNF */
			if (flag&JOBDIR &&
			    !eq(tp->p_cwd->di_name, dcwd->di_name)) {
				csh_printf(" (wd: ");		/* 004 RNF */
				dtildepr(value("home"), tp->p_cwd->di_name);
				csh_printf(")");		/* 004 RNF */
			}
		}
		if (pp->p_flags&PPTIME && !(status&(PSTOPPED|PRUNNING))) {
			if (linp != linbuf)
				csh_printf("\n\t");		/* 004 RNF */
			{ static struct rusage zru;
			  prusage(&zru, &pp->p_rusage, &pp->p_etime,
			    &pp->p_btime);
			}
		}
		if (tp == pp->p_friends) {
			if (linp != linbuf)
				csh_printf("\n");		/* 004 RNF */
			if (flag&SHELLDIR && !eq(tp->p_cwd->di_name, dcwd->di_name)) {
				csh_printf("(wd now: ");	/* 004 RNF */
				dtildepr(value("home"), dcwd->di_name);
				csh_printf(")\n");		/* 004 RNF */
			}
		}
	} while ((pp = pp->p_friends) != tp);
	if (jobflags&PTIME && (jobflags&(PSTOPPED|PRUNNING)) == 0) {
		if (jobflags & NUMBER)
			csh_printf("       ");			/* 004 RNF */
		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)
					csh_printf("%s ", name); /* 004 RNF */
				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 SIGCONT:
				np->p_flags |= PRUNNING;
				np->p_flags &= ~PSTOPPED;
				break;

			case SIGSTOP:
			case SIGTSTP:
			case SIGTTIN:
			case SIGTTOU:
				if ((jobflags & PRUNNING) == 0) {
					csh_printf("%s: Already stopped\n", cp); /* 004 RNF */
					err++;
					goto cont;
				}
			}
			if (killpg(pp->p_jobid, signum) < 0) {
				csh_printf("%s: ", cp);		/* 004 RNF */
				csh_printf("%s\n", sys_errlist[errno]); /* 004 RNF */
				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) {
				csh_printf("%d: ", pid);	/* 004 RNF */
				csh_printf("%s\n", sys_errlist[errno]); /* 004 RNF */
				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);	/* 002 - GAG */
	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); 			/* 003 RNF */
		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);	/* 002 - GAG */
		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");
}