jobs.c

Android 一些工具

/*	$NetBSD: jobs.c,v 1.62 2003/12/18 00:56:05 christos Exp $	*/

/*-
 * 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. 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.
 */

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)jobs.c	8.5 (Berkeley) 5/4/95";
#else
__RCSID("$NetBSD: jobs.c,v 1.62 2003/12/18 00:56:05 christos Exp $");
#endif
#endif /* not lint */

#include <fcntl.h>
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#define _PATH_DEVNULL "/dev/null"
#include <sys/types.h>
#include <sys/param.h>
#ifdef BSD
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#endif
#include <sys/wait.h>
#define killpg(s,i) kill(-(s),i)
#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"

// Use of process groups is disabled to allow adb shell children to terminate when the shell dies
#define USE_PROCESS_GROUPS


static struct job *jobtab;		/* array of jobs */
static int njobs;			/* size of array */
static int jobs_invalid;		/* set in child */
MKINIT pid_t backgndpid = -1;	/* pid of last background process */
#if JOBS
int initialpgrp;		/* pgrp of shell on invocation */
static int curjob = -1;		/* current job */
#endif
static int ttyfd = -1;

STATIC void restartjob(struct job *);
STATIC void freejob(struct job *);
STATIC struct job *getjob(const char *, int);
STATIC int dowait(int, struct job *);
STATIC int onsigchild(void);
STATIC int waitproc(int, struct job *, int *);
STATIC void cmdtxt(union node *);
STATIC void cmdlist(union node *, int);
STATIC void cmdputs(const char *);

#ifdef OLD_TTY_DRIVER
static pid_t tcgetpgrp(int fd);
static int tcsetpgrp(int fd, pid_t pgrp);

static pid_t
tcgetpgrp(int fd)
{
	pid_t pgrp;
	if (ioctl(fd, TIOCGPGRP, (char *)&pgrp) == -1)
		return -1;
	else
		return pgrp;
}

static int
tcsetpgrp(int fd, pid_tpgrp)
{
	return ioctl(fd, TIOCSPGRP, (char *)&pgrp);
}
#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(int on)
{
#ifdef OLD_TTY_DRIVER
	int ldisc;
#endif

	if (on == jobctl || rootshell == 0)
		return;
	if (on) {
#if defined(FIOCLEX) || defined(FD_CLOEXEC)
		int err;
		int i;
		if (ttyfd != -1)
			close(ttyfd);
		if ((ttyfd = open("/dev/tty", O_RDWR)) == -1) {
			for (i = 0; i < 3; i++) {
				if (isatty(i) && (ttyfd = dup(i)) != -1)
					break;
			}
			if (i == 3)
				goto out;
		}
		/* Move to a high fd */
		for (i = 10; i > 2; i--) {
			if ((err = fcntl(ttyfd, F_DUPFD, (1 << i) - 1)) != -1)
				break;
		}
		if (err != -1) {
			close(ttyfd);
			ttyfd = err;
		}
#ifdef FIOCLEX
		err = ioctl(ttyfd, FIOCLEX, 0);
#elif FD_CLOEXEC
		err = fcntl(ttyfd, F_SETFD,
		    fcntl(ttyfd, F_GETFD, 0) | FD_CLOEXEC);
#endif
		if (err == -1) {
			close(ttyfd);
			ttyfd = -1;
			goto out;
		}
#else
		out2str("sh: Need FIOCLEX or FD_CLOEXEC to support job control");
		goto out;
#endif
		do { /* while we are in the background */
			if ((initialpgrp = tcgetpgrp(ttyfd)) < 0) {
out:
				out2str("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);

#ifdef OLD_TTY_DRIVER
		if (ioctl(ttyfd, 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, 0);
		setsignal(SIGTTOU, 0);
		setsignal(SIGTTIN, 0);
#ifdef USE_PROCESS_GROUPS
		if (getpgid(0) != rootpid && setpgid(0, rootpid) == -1)
			error("Cannot set process group (%s) at %d",
			    strerror(errno), __LINE__);
		if (tcsetpgrp(ttyfd, rootpid) == -1)
			error("Cannot set tty process group (%s) at %d",
			    strerror(errno), __LINE__);
#endif
	} else { /* turning job control off */
#ifdef USE_PROCESS_GROUPS
		if (getpgid(0) != initialpgrp && setpgid(0, initialpgrp) == -1)
			error("Cannot set process group (%s) at %d",
			    strerror(errno), __LINE__);
		if (tcsetpgrp(ttyfd, initialpgrp) == -1)
			error("Cannot set tty process group (%s) at %d",
			    strerror(errno), __LINE__);
#endif
		close(ttyfd);
		ttyfd = -1;
		setsignal(SIGTSTP, 0);
		setsignal(SIGTTOU, 0);
		setsignal(SIGTTIN, 0);
	}
	jobctl = on;
}


#ifdef mkinit
INCLUDE <stdlib.h>

SHELLPROC {
	backgndpid = -1;
#if JOBS
	jobctl = 0;
#endif
}

#endif



#if JOBS
int
fgcmd(int argc, char **argv)
{
	struct job *jp;
	int i;
	int status;

	nextopt("");
	jp = getjob(*argptr, 0);
	if (jp->jobctl == 0)
		error("job not created under job control");
	out1fmt("%s", jp->ps[0].cmd);
	for (i = 1; i < jp->nprocs; i++)
		out1fmt(" | %s", jp->ps[i].cmd );
	out1c('\n');
	flushall();

	for (i = 0; i < jp->nprocs; i++)
	    if (tcsetpgrp(ttyfd, jp->ps[i].pid) != -1)
		    break;

	if (i >= jp->nprocs) {
		error("Cannot set tty process group (%s) at %d",
		    strerror(errno), __LINE__);
	}
	restartjob(jp);
	INTOFF;
	status = waitforjob(jp);
	INTON;
	return status;
}

static void
set_curjob(struct job *jp, int mode)
{
	struct job *jp1, *jp2;
	int i, ji;

	ji = jp - jobtab;

	/* first remove from list */
	if (ji == curjob)
		curjob = jp->prev_job;
	else {
		for (i = 0; i < njobs; i++) {
			if (jobtab[i].prev_job != ji)
				continue;
			jobtab[i].prev_job = jp->prev_job;
			break;
		}
	}

	/* Then re-insert in correct position */
	switch (mode) {
	case 0:	/* job being deleted */
		jp->prev_job = -1;
		break;
	case 1:	/* newly created job or backgrounded job,
		   put after all stopped jobs. */
		if (curjob != -1 && jobtab[curjob].state == JOBSTOPPED) {
			for (jp1 = jobtab + curjob; ; jp1 = jp2) {
				if (jp1->prev_job == -1)
					break;
				jp2 = jobtab + jp1->prev_job;
				if (jp2->state != JOBSTOPPED)
					break;
			}
			jp->prev_job = jp1->prev_job;
			jp1->prev_job = ji;
			break;
		}
		/* FALLTHROUGH */
	case 2:	/* newly stopped job - becomes curjob */
		jp->prev_job = curjob;
		curjob = ji;
		break;
	}
}

int
bgcmd(int argc, char **argv)
{
	struct job *jp;
	int i;

	nextopt("");
	do {
		jp = getjob(*argptr, 0);
		if (jp->jobctl == 0)
			error("job not created under job control");
		set_curjob(jp, 1);
		out1fmt("[%ld] %s", (long)(jp - jobtab + 1), jp->ps[0].cmd);
		for (i = 1; i < jp->nprocs; i++)
			out1fmt(" | %s", jp->ps[i].cmd );
		out1c('\n');
		flushall();
		restartjob(jp);
	} while (*argptr && *++argptr);
	return 0;
}


STATIC void
restartjob(struct job *jp)
{
	struct procstat *ps;
	int i;

	if (jp->state == JOBDONE)
		return;
	INTOFF;
	for (i = 0; i < jp->nprocs; i++)
		if (killpg(jp->ps[i].pid, SIGCONT) != -1)
			break;
	if (i >= jp->nprocs)
		error("Cannot continue job (%s)", strerror(errno));
	for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
		if (WIFSTOPPED(ps->status)) {
			ps->status = -1;
			jp->state = JOBRUNNING;
		}
	}
	INTON;
}
#endif

static void
showjob(struct output *out, struct job *jp, int mode)
{
	int procno;
	int st;
	struct procstat *ps;
	int col;
	char s[64];

#if JOBS
	if (mode & SHOW_PGID) {
		/* just output process (group) id of pipeline */
		outfmt(out, "%ld\n", (long)jp->ps->pid);
		return;
	}
#endif

	procno = jp->nprocs;
	if (!procno)
		return;

	if (mode & SHOW_PID)
		mode |= SHOW_MULTILINE;

	if ((procno > 1 && !(mode & SHOW_MULTILINE))
	    || (mode & SHOW_SIGNALLED)) {
		/* See if we have more than one status to report */
		ps = jp->ps;
		st = ps->status;
		do {
			int st1 = ps->status;
			if (st1 != st)
				/* yes - need multi-line output */
				mode |= SHOW_MULTILINE;
			if (st1 == -1 || !(mode & SHOW_SIGNALLED) || WIFEXITED(st1))
				continue;
			if (WIFSTOPPED(st1) || ((st1 = WTERMSIG(st1) & 0x7f)
			    && st1 != SIGINT && st1 != SIGPIPE))
				mode |= SHOW_ISSIG;

		} while (ps++, --procno);
		procno = jp->nprocs;
	}

	if (mode & SHOW_SIGNALLED && !(mode & SHOW_ISSIG)) {
		if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE)) {
			TRACE(("showjob: freeing job %d\n", jp - jobtab + 1));
			freejob(jp);
		}
		return;
	}

	for (ps = jp->ps; --procno >= 0; ps++) {	/* for each process */
		if (ps == jp->ps)
			fmtstr(s, 16, "[%ld] %c ",
				(long)(jp - jobtab + 1),
#if JOBS
				jp == jobtab + curjob ? '+' :
				curjob != -1 && jp == jobtab +
					    jobtab[curjob].prev_job ? '-' :
#endif
				' ');
		else
			fmtstr(s, 16, "      " );
		col = strlen(s);
		if (mode & SHOW_PID) {
			fmtstr(s + col, 16, "%ld ", (long)ps->pid);
			     col += strlen(s + col);
		}
		if (ps->status == -1) {
			scopy("Running", s + col);
		} else if (WIFEXITED(ps->status)) {
			st = WEXITSTATUS(ps->status);
			if (st)
				fmtstr(s + col, 16, "Done(%d)", st);
			else
				fmtstr(s + col, 16, "Done");
		} else {
#if JOBS
			if (WIFSTOPPED(ps->status)) 
				st = WSTOPSIG(ps->status);
			else /* WIFSIGNALED(ps->status) */
#endif
				st = WTERMSIG(ps->status);
			st &= 0x7f;
			if (st < NSIG && sys_siglist[st])
				scopyn(sys_siglist[st], s + col, 32);
			else
				fmtstr(s + col, 16, "Signal %d", st);
			if (WCOREDUMP(ps->status)) {
				col += strlen(s + col);
				scopyn(" (core dumped)", s + col,  64 - col);
			}
		}
		col += strlen(s + col);
		outstr(s, out);
		do {
			outc(' ', out);
			col++;
		} while (col < 30);
		outstr(ps->cmd, out);
		if (mode & SHOW_MULTILINE) {
			if (procno > 0) {
				outc(' ', out);
				outc('|', out);
			}
		} else {
			while (--procno >= 0)
				outfmt(out, " | %s", (++ps)->cmd );
		}
		outc('\n', out);
	}
	flushout(out);
	jp->changed = 0;
	if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE))
		freejob(jp);