2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95";
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include <sys/ioctl.h>
42 #include <sys/param.h>
43 #include <sys/resource.h>
57 #undef CEOF /* syntax.h redefines this */
75 static struct job *jobtab; /* array of jobs */
76 static int njobs; /* size of array */
77 MKINIT pid_t backgndpid = -1; /* pid of last background process */
78 MKINIT struct job *bgjob = NULL; /* last background process */
80 static struct job *jobmru; /* most recently used job list */
81 static pid_t initialpgrp; /* pgrp of shell on invocation */
83 int in_waitcmd = 0; /* are we in waitcmd()? */
84 int in_dowait = 0; /* are we in dowait()? */
85 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */
86 static int ttyfd = -1;
89 static void restartjob(struct job *);
91 static void freejob(struct job *);
92 static struct job *getjob(char *);
93 static pid_t dowait(int, struct job *);
94 static pid_t waitproc(int, int *);
95 static void checkzombies(void);
96 static void cmdtxt(union node *);
97 static void cmdputs(const char *);
99 static void setcurjob(struct job *);
100 static void deljob(struct job *);
101 static struct job *getcurjob(struct job *);
103 static void showjob(struct job *, pid_t, int);
107 * Turn job control on and off.
118 if (on == jobctl || rootshell == 0)
123 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) {
125 while (i <= 2 && !isatty(i))
127 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0)
132 * Keep our TTY file descriptor out of the way of
133 * the user's redirections.
135 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) {
143 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) {
148 do { /* while we are in the background */
149 initialpgrp = tcgetpgrp(ttyfd);
150 if (initialpgrp < 0) {
151 out: out2fmt_flush("sh: can't access tty; job control turned off\n");
155 if (initialpgrp == -1)
156 initialpgrp = getpgrp();
157 else if (initialpgrp != getpgrp()) {
166 tcsetpgrp(ttyfd, rootpid);
167 } else { /* turning job control off */
168 setpgid(0, initialpgrp);
169 tcsetpgrp(ttyfd, initialpgrp);
182 INCLUDE <sys/types.h>
199 fgcmd(int argc __unused, char **argv)
205 jp = getjob(argv[1]);
207 error("job not created under job control");
208 out1str(jp->ps[0].cmd);
211 pgrp = jp->ps[0].pid;
212 tcsetpgrp(ttyfd, pgrp);
216 status = waitforjob(jp, (int *)NULL);
223 bgcmd(int argc, char **argv)
229 jp = getjob(*++argv);
231 error("job not created under job control");
232 if (jp->state == JOBDONE)
236 fmtstr(s, 64, "[%td] ", jp - jobtab + 1);
238 out1str(jp->ps[0].cmd);
240 } while (--argc > 1);
246 restartjob(struct job *jp)
251 if (jp->state == JOBDONE)
255 killpg(jp->ps[0].pid, SIGCONT);
256 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
257 if (WIFSTOPPED(ps->status)) {
268 jobscmd(int argc, char *argv[])
273 optind = optreset = 1;
275 mode = SHOWJOBS_DEFAULT;
276 while ((ch = getopt(argc, argv, "lps")) != -1) {
279 mode = SHOWJOBS_VERBOSE;
282 mode = SHOWJOBS_PGIDS;
285 mode = SHOWJOBS_PIDS;
289 error("unknown option: -%c", optopt);
298 while ((id = *argv++) != NULL)
299 showjob(getjob(id), 0, mode);
305 showjob(struct job *jp, pid_t pid, int mode)
310 int col, curr, i, jobno, prev, procno;
314 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs;
315 jobno = jp - jobtab + 1;
318 if ((j = getcurjob(NULL)) != NULL) {
319 curr = j - jobtab + 1;
320 if ((j = getcurjob(j)) != NULL)
321 prev = j - jobtab + 1;
324 for (ps = jp->ps ; ; ps++) { /* for each process */
325 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) {
326 ppid = (mode == SHOWJOBS_PIDS) ? ps->pid :
328 out1fmt("%d\n", (int)ppid);
331 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps && pid == 0)
333 if (pid != 0 && pid != ps->pid)
335 if (jobno == curr && ps == jp->ps)
337 else if (jobno == prev && ps == jp->ps)
342 fmtstr(s, 64, "[%d] %c ", jobno, c);
344 fmtstr(s, 64, " %c ", c);
347 if (mode == SHOWJOBS_VERBOSE) {
348 fmtstr(s, 64, "%d ", (int)ps->pid);
355 } else if (ps->status == -1) {
356 strcpy(s, "Running");
357 } else if (WIFEXITED(ps->status)) {
358 if (WEXITSTATUS(ps->status) == 0)
361 fmtstr(s, 64, "Done (%d)",
362 WEXITSTATUS(ps->status));
365 if (WIFSTOPPED(ps->status))
366 i = WSTOPSIG(ps->status);
369 i = WTERMSIG(ps->status);
370 if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F])
371 scopy(sys_siglist[i & 0x7F], s);
373 fmtstr(s, 64, "Signal %d", i & 0x7F);
374 if (WCOREDUMP(ps->status))
375 strcat(s, " (core dumped)");
385 skip: if (--procno <= 0)
391 * Print a list of jobs. If "change" is nonzero, only print jobs whose
392 * statuses have changed since the last call to showjobs.
394 * If the shell is interrupted in the process of creating a job, the
395 * result may be a job structure containing zero processes. Such structures
396 * will be freed here.
400 showjobs(int change, int mode)
405 TRACE(("showjobs(%d) called\n", change));
407 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) {
410 if (jp->nprocs == 0) {
414 if (change && ! jp->changed)
416 showjob(jp, 0, mode);
418 /* Hack: discard jobs for which $! has not been referenced
419 * in interactive mode when they terminate.
421 if (jp->state == JOBDONE && !jp->remembered &&
422 (iflag || jp != bgjob)) {
430 * Mark a job structure as unused.
434 freejob(struct job *jp)
442 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) {
443 if (ps->cmd != nullstr)
446 if (jp->ps != &jp->ps0)
458 waitcmd(int argc, char **argv)
465 job = getjob(argv[1]);
471 * Loop until a process is terminated or stopped, or a SIGINT is
479 status = job->ps[job->nprocs - 1].status;
480 if (WIFEXITED(status))
481 retval = WEXITSTATUS(status);
483 else if (WIFSTOPPED(status))
484 retval = WSTOPSIG(status) + 128;
487 retval = WTERMSIG(status) + 128;
488 if (! iflag || ! job->changed)
499 for (jp = jobtab ; jp < jobtab + njobs; jp++)
500 if (jp->used && jp->state == JOBDONE) {
501 if (! iflag || ! jp->changed)
509 for (jp = jobtab ; ; jp++) {
510 if (jp >= jobtab + njobs) { /* no running procs */
514 if (jp->used && jp->state == 0)
518 } while (dowait(1, (struct job *)NULL) != -1);
527 jobidcmd(int argc __unused, char **argv)
532 jp = getjob(argv[1]);
533 for (i = 0 ; i < jp->nprocs ; ) {
534 out1fmt("%d", (int)jp->ps[i].pid);
535 out1c(++i < jp->nprocs? ' ' : '\n');
543 * Convert a job name to a job structure.
550 struct job *found, *jp;
556 currentjob: if ((jp = getcurjob(NULL)) == NULL)
557 error("No current job");
560 error("No current job");
562 } else if (name[0] == '%') {
563 if (is_digit(name[1])) {
564 jobno = number(name + 1);
565 if (jobno > 0 && jobno <= njobs
566 && jobtab[jobno - 1].used != 0)
567 return &jobtab[jobno - 1];
569 } else if (name[1] == '%' && name[2] == '\0') {
571 } else if (name[1] == '+' && name[2] == '\0') {
573 } else if (name[1] == '-' && name[2] == '\0') {
574 if ((jp = getcurjob(NULL)) == NULL ||
575 (jp = getcurjob(jp)) == NULL)
576 error("No previous job");
579 } else if (name[1] == '?') {
581 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
582 if (jp->used && jp->nprocs > 0
583 && strstr(jp->ps[0].cmd, name + 2) != NULL) {
585 error("%s: ambiguous", name);
593 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
594 if (jp->used && jp->nprocs > 0
595 && prefix(name + 1, jp->ps[0].cmd)) {
597 error("%s: ambiguous", name);
604 } else if (is_number(name)) {
605 pid = (pid_t)number(name);
606 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
607 if (jp->used && jp->nprocs > 0
608 && jp->ps[jp->nprocs - 1].pid == pid)
612 error("No such job: %s", name);
620 * Return a new job structure,
624 makejob(union node *node __unused, int nprocs)
629 for (i = njobs, jp = jobtab ; ; jp++) {
633 jobtab = ckmalloc(4 * sizeof jobtab[0]);
638 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]);
639 memcpy(jp, jobtab, njobs * sizeof jp[0]);
641 /* Relocate `next' pointers and list head */
643 jobmru = &jp[jobmru - jobtab];
644 for (i = 0; i < njobs; i++)
645 if (jp[i].next != NULL)
646 jp[i].next = &jp[jp[i].next -
650 bgjob = &jp[bgjob - jobtab];
651 /* Relocate `ps' pointers */
652 for (i = 0; i < njobs; i++)
653 if (jp[i].ps == &jobtab[i].ps0)
654 jp[i].ps = &jp[i].ps0;
659 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0);
678 jp->ps = ckmalloc(nprocs * sizeof (struct procstat));
683 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs,
690 setcurjob(struct job *cj)
692 struct job *jp, *prev;
694 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
697 prev->next = jp->next;
710 deljob(struct job *j)
712 struct job *jp, *prev;
714 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
717 prev->next = jp->next;
726 * Return the most recently used job that isn't `nj', and preferably one
730 getcurjob(struct job *nj)
734 /* Try to find a stopped one.. */
735 for (jp = jobmru; jp != NULL; jp = jp->next)
736 if (jp->used && jp != nj && jp->state == JOBSTOPPED)
738 /* Otherwise the most recently used job that isn't `nj' */
739 for (jp = jobmru; jp != NULL; jp = jp->next)
740 if (jp->used && jp != nj)
749 * Fork of a subshell. If we are doing job control, give the subshell its
750 * own process group. Jp is a job structure that the job is to be added to.
751 * N is the command that will be evaluated by the child. Both jp and n may
752 * be NULL. The mode parameter can be one of the following:
753 * FORK_FG - Fork off a foreground process.
754 * FORK_BG - Fork off a background process.
755 * FORK_NOJOB - Like FORK_FG, but don't give the process its own
756 * process group even if job control is on.
758 * When job control is turned off, background processes have their standard
759 * input redirected to /dev/null (except for the second and later processes
764 forkshell(struct job *jp, union node *n, int mode)
769 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n,
777 TRACE(("Fork failed, errno=%d\n", errno));
779 error("Cannot fork: %s", strerror(errno));
786 TRACE(("Child shell %d\n", (int)getpid()));
789 handler = &main_handler;
794 jobctl = 0; /* do job control only in root shell */
795 if (wasroot && mode != FORK_NOJOB && mflag) {
796 if (jp == NULL || jp->nprocs == 0)
799 pgrp = jp->ps[0].pid;
800 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) {
801 /*** this causes superfluous TIOCSPGRPS ***/
802 if (tcsetpgrp(ttyfd, pgrp) < 0)
803 error("tcsetpgrp failed, errno=%d", errno);
807 } else if (mode == FORK_BG) {
810 if ((jp == NULL || jp->nprocs == 0) &&
811 ! fd0_redirected_p ()) {
813 if (open(_PATH_DEVNULL, O_RDONLY) != 0)
814 error("Can't open %s: %s",
815 _PATH_DEVNULL, strerror(errno));
819 if (mode == FORK_BG) {
822 if ((jp == NULL || jp->nprocs == 0) &&
823 ! fd0_redirected_p ()) {
825 if (open(_PATH_DEVNULL, O_RDONLY) != 0)
826 error("Can't open %s: %s",
827 _PATH_DEVNULL, strerror(errno));
832 for (i = njobs, p = jobtab ; --i >= 0 ; p++)
836 if (wasroot && iflag) {
843 if (rootshell && mode != FORK_NOJOB && mflag) {
844 if (jp == NULL || jp->nprocs == 0)
847 pgrp = jp->ps[0].pid;
850 if (mode == FORK_BG) {
851 if (bgjob != NULL && bgjob->state == JOBDONE &&
852 !bgjob->remembered && !iflag)
854 backgndpid = pid; /* set $! */
858 struct procstat *ps = &jp->ps[jp->nprocs++];
862 if (iflag && rootshell && n)
863 ps->cmd = commandtext(n);
864 jp->foreground = mode == FORK_FG;
870 TRACE(("In parent shell: child = %d\n", (int)pid));
877 * Wait for job to finish.
879 * Under job control we have the problem that while a child process is
880 * running interrupts generated by the user are sent to the child but not
881 * to the shell. This means that an infinite loop started by an inter-
882 * active user may be hard to kill. With job control turned off, an
883 * interactive user may place an interactive program inside a loop. If
884 * the interactive program catches interrupts, the user doesn't want
885 * these interrupts to also abort the loop. The approach we take here
886 * is to have the shell ignore interrupt signals while waiting for a
887 * foreground process to terminate, and then send itself an interrupt
888 * signal if the child process was terminated by an interrupt signal.
889 * Unfortunately, some programs want to do a bit of cleanup and then
890 * exit on interrupt; unless these processes terminate themselves by
891 * sending a signal to themselves (instead of calling exit) they will
892 * confuse this approach.
896 waitforjob(struct job *jp, int *origstatus)
899 pid_t mypgrp = getpgrp();
900 int propagate_int = jp->jobctl && jp->foreground;
906 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1));
907 while (jp->state == 0)
908 if (dowait(1, jp) == -1)
912 if (tcsetpgrp(ttyfd, mypgrp) < 0)
913 error("tcsetpgrp failed, errno=%d\n", errno);
915 if (jp->state == JOBSTOPPED)
918 status = jp->ps[jp->nprocs - 1].status;
919 if (origstatus != NULL)
920 *origstatus = status;
921 /* convert to 8 bits */
922 if (WIFEXITED(status))
923 st = WEXITSTATUS(status);
925 else if (WIFSTOPPED(status))
926 st = WSTOPSIG(status) + 128;
929 st = WTERMSIG(status) + 128;
930 if (! JOBS || jp->state == JOBDONE)
933 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
934 kill(getpid(), SIGINT);
939 else if (rootshell && iflag && propagate_int &&
940 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
941 kill(getpid(), SIGINT);
950 * Wait for a process to terminate.
954 dowait(int block, struct job *job)
967 TRACE(("dowait(%d) called\n", block));
969 pid = waitproc(block, &status);
970 TRACE(("wait returns %d, status=%d\n", (int)pid, status));
971 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) ||
972 (pid > 0 && WIFSTOPPED(status) && !iflag));
974 if (pid == -1 && errno == ECHILD && job != NULL)
975 job->state = JOBDONE;
976 if (breakwaitcmd != 0) {
985 for (jp = jobtab ; jp < jobtab + njobs ; jp++) {
989 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) {
992 if (sp->pid == pid) {
993 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n",
994 (int)pid, sp->status,
999 if (sp->status == -1)
1001 else if (WIFSTOPPED(sp->status))
1004 if (stopped) { /* stopped or done */
1005 int state = done? JOBDONE : JOBSTOPPED;
1006 if (jp->state != state) {
1007 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state));
1010 if (done && !jp->remembered &&
1011 !iflag && jp != bgjob)
1023 if (! rootshell || ! iflag || (job && thisjob == job)) {
1025 if (WIFSTOPPED(status))
1026 sig = WSTOPSIG(status);
1030 if (WIFEXITED(status))
1033 sig = WTERMSIG(status);
1035 if (sig != 0 && sig != SIGINT && sig != SIGPIPE) {
1037 (thisjob->foreground && !WIFSTOPPED(status))) {
1038 i = WTERMSIG(status);
1039 if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F])
1040 out1str(sys_siglist[i & 0x7F]);
1042 out1fmt("Signal %d", i & 0x7F);
1043 if (WCOREDUMP(status))
1044 out1str(" (core dumped)");
1047 showjob(thisjob, pid, SHOWJOBS_DEFAULT);
1050 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job));
1052 thisjob->changed = 1;
1060 * Do a wait system call. If job control is compiled in, we accept
1061 * stopped processes. If block is zero, we return a value of zero
1062 * rather than blocking.
1065 waitproc(int block, int *status)
1076 return wait3(status, flags, (struct rusage *)NULL);
1080 * return 1 if there are stopped jobs, otherwise 0
1082 int job_warning = 0;
1091 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) {
1094 if (jp->state == JOBSTOPPED) {
1095 out2fmt_flush("You have stopped jobs.\n");
1108 while (njobs > 0 && dowait(0, NULL) > 0)
1116 return backgndpid != -1;
1124 bgjob->remembered = 1;
1129 * Return a string identifying a command (to be printed by the
1133 static char *cmdnextc;
1134 static int cmdnleft;
1135 #define MAXCMDTEXT 200
1138 commandtext(union node *n)
1142 cmdnextc = name = ckmalloc(MAXCMDTEXT);
1143 cmdnleft = MAXCMDTEXT - 4;
1151 cmdtxt(union node *n)
1154 struct nodelist *lp;
1163 cmdtxt(n->nbinary.ch1);
1165 cmdtxt(n->nbinary.ch2);
1168 cmdtxt(n->nbinary.ch1);
1170 cmdtxt(n->nbinary.ch2);
1173 cmdtxt(n->nbinary.ch1);
1175 cmdtxt(n->nbinary.ch2);
1178 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
1186 cmdtxt(n->nredir.n);
1191 cmdtxt(n->nredir.n);
1195 cmdtxt(n->nif.test);
1197 cmdtxt(n->nif.ifpart);
1206 cmdtxt(n->nbinary.ch1);
1208 cmdtxt(n->nbinary.ch2);
1213 cmdputs(n->nfor.var);
1218 cmdputs(n->ncase.expr->narg.text);
1222 cmdputs(n->narg.text);
1226 for (np = n->ncmd.args ; np ; np = np->narg.next) {
1231 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) {
1237 cmdputs(n->narg.text);
1240 p = ">"; i = 1; goto redir;
1242 p = ">>"; i = 1; goto redir;
1244 p = ">&"; i = 1; goto redir;
1246 p = ">|"; i = 1; goto redir;
1248 p = "<"; i = 0; goto redir;
1250 p = "<>"; i = 0; goto redir;
1252 p = "<&"; i = 0; goto redir;
1254 if (n->nfile.fd != i) {
1255 s[0] = n->nfile.fd + '0';
1260 if (n->type == NTOFD || n->type == NFROMFD) {
1261 if (n->ndup.dupfd >= 0)
1262 s[0] = n->ndup.dupfd + '0';
1268 cmdtxt(n->nfile.fname);
1284 cmdputs(const char *s)
1295 while ((c = *p++) != '\0') {
1298 else if (c == CTLVAR) {
1303 } else if (c == '=' && subtype != 0) {
1304 *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL];
1306 } else if (c == CTLENDVAR) {
1308 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE)
1309 cmdnleft++; /* ignore it */
1312 if (--cmdnleft <= 0) {