jobs.c revision 72086
182518Sgallatin/*- 282518Sgallatin * Copyright (c) 1991, 1993 382518Sgallatin * The Regents of the University of California. All rights reserved. 482518Sgallatin * 582518Sgallatin * This code is derived from software contributed to Berkeley by 682518Sgallatin * Kenneth Almquist. 782518Sgallatin * 882518Sgallatin * Redistribution and use in source and binary forms, with or without 982518Sgallatin * modification, are permitted provided that the following conditions 1082518Sgallatin * are met: 1182518Sgallatin * 1. Redistributions of source code must retain the above copyright 1282518Sgallatin * notice, this list of conditions and the following disclaimer. 1382518Sgallatin * 2. Redistributions in binary form must reproduce the above copyright 1482518Sgallatin * notice, this list of conditions and the following disclaimer in the 1582518Sgallatin * documentation and/or other materials provided with the distribution. 1682518Sgallatin * 3. All advertising materials mentioning features or use of this software 1782518Sgallatin * must display the following acknowledgement: 1882518Sgallatin * This product includes software developed by the University of 1982518Sgallatin * California, Berkeley and its contributors. 2082518Sgallatin * 4. Neither the name of the University nor the names of its contributors 2182518Sgallatin * may be used to endorse or promote products derived from this software 2282518Sgallatin * without specific prior written permission. 2382518Sgallatin * 2482518Sgallatin * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2582518Sgallatin * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2682518Sgallatin * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2782518Sgallatin * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2882518Sgallatin * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2982518Sgallatin * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 3082518Sgallatin * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 3182518Sgallatin * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 3282518Sgallatin * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3382518Sgallatin * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3482518Sgallatin * SUCH DAMAGE. 3582518Sgallatin */ 3682518Sgallatin 3782518Sgallatin#ifndef lint 38116173Sobrien#if 0 39116173Sobrienstatic char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 40116173Sobrien#endif 41116173Sobrienstatic const char rcsid[] = 42112430Sphk "$FreeBSD: head/bin/sh/jobs.c 72086 2001-02-06 10:29:34Z cracauer $"; 43112430Sphk#endif /* not lint */ 4482518Sgallatin 4582518Sgallatin#include <fcntl.h> 4682518Sgallatin#include <signal.h> 47112430Sphk#include <errno.h> 48112430Sphk#include <unistd.h> 49112430Sphk#include <stdlib.h> 50112430Sphk#include <sys/param.h> 51112430Sphk#ifdef BSD 52102872Siedowse#include <sys/wait.h> 53112430Sphk#include <sys/time.h> 54112430Sphk#include <sys/resource.h> 5582518Sgallatin#include <paths.h> 56112430Sphk#endif 57112430Sphk#include <sys/ioctl.h> 58112430Sphk 59112430Sphk#include "shell.h" 60112430Sphk#if JOBS 6182518Sgallatin#if OLD_TTY_DRIVER 62133816Stjr#include "sgtty.h" 63133816Stjr#else 64140214Sobrien#include <termios.h> 65140214Sobrien#endif 66140214Sobrien#undef CEOF /* syntax.h redefines this */ 67140214Sobrien#endif 6882518Sgallatin#include "redir.h" 6982518Sgallatin#include "show.h" 70133816Stjr#include "main.h" 71112430Sphk#include "parser.h" 7282518Sgallatin#include "nodes.h" 73112430Sphk#include "jobs.h" 74112430Sphk#include "options.h" 75112430Sphk#include "trap.h" 76112430Sphk#include "syntax.h" 77112430Sphk#include "input.h" 78112430Sphk#include "output.h" 79112430Sphk#include "memalloc.h" 80112430Sphk#include "error.h" 81112430Sphk#include "mystring.h" 8282518Sgallatin 83112430Sphk 84112430Sphkstruct job *jobtab; /* array of jobs */ 85112430Sphkint njobs; /* size of array */ 86112430SphkMKINIT pid_t backgndpid = -1; /* pid of last background process */ 87112430Sphk#if JOBS 88112430Sphkint initialpgrp; /* pgrp of shell on invocation */ 89112430Sphkint curjob; /* current job */ 90112430Sphk#endif 91112430Sphkint in_waitcmd = 0; /* are we in waitcmd()? */ 92112430Sphkint in_dowait = 0; /* are we in dowait()? */ 93112430Sphkvolatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 94112430Sphk 95112430Sphk#if JOBS 96112430SphkSTATIC void restartjob __P((struct job *)); 97112430Sphk#endif 98112430SphkSTATIC void freejob __P((struct job *)); 99112430SphkSTATIC struct job *getjob __P((char *)); 100112430SphkSTATIC int dowait __P((int, struct job *)); 101112430Sphk#if SYSV 102112430SphkSTATIC int onsigchild __P((void)); 103112430Sphk#endif 104112430SphkSTATIC int waitproc __P((int, int *)); 105112430SphkSTATIC void cmdtxt __P((union node *)); 106112430SphkSTATIC void cmdputs __P((char *)); 107112430Sphk 108112430Sphk 109112430Sphk/* 110112430Sphk * Turn job control on and off. 111112430Sphk * 112112430Sphk * Note: This code assumes that the third arg to ioctl is a character 113112430Sphk * pointer, which is true on Berkeley systems but not System V. Since 114112430Sphk * System V doesn't have job control yet, this isn't a problem now. 115112430Sphk */ 116112430Sphk 117112430SphkMKINIT int jobctl; 118112430Sphk 119112430Sphk#if JOBS 120112430Sphkvoid 121112430Sphksetjobctl(on) 122112430Sphk int on; 123112430Sphk{ 124112430Sphk#ifdef OLD_TTY_DRIVER 125112430Sphk int ldisc; 126112430Sphk#endif 127112430Sphk 128112430Sphk if (on == jobctl || rootshell == 0) 129112430Sphk return; 130112430Sphk if (on) { 131112430Sphk do { /* while we are in the background */ 132112430Sphk#ifdef OLD_TTY_DRIVER 133112430Sphk if (ioctl(2, TIOCGPGRP, (char *)&initialpgrp) < 0) { 134112430Sphk#else 135112430Sphk initialpgrp = tcgetpgrp(2); 136112430Sphk if (initialpgrp < 0) { 137112430Sphk#endif 138112430Sphk out2str("sh: can't access tty; job control turned off\n"); 139112430Sphk mflag = 0; 140112430Sphk return; 141112430Sphk } 142112430Sphk if (initialpgrp == -1) 143112430Sphk initialpgrp = getpgrp(); 144112430Sphk else if (initialpgrp != getpgrp()) { 145112430Sphk killpg(initialpgrp, SIGTTIN); 146112430Sphk continue; 147112430Sphk } 148112430Sphk } while (0); 149112430Sphk#ifdef OLD_TTY_DRIVER 150112430Sphk if (ioctl(2, TIOCGETD, (char *)&ldisc) < 0 || ldisc != NTTYDISC) { 151112430Sphk out2str("sh: need new tty driver to run job control; job control turned off\n"); 152112430Sphk mflag = 0; 153112430Sphk return; 154112430Sphk } 155112430Sphk#endif 156112430Sphk setsignal(SIGTSTP); 157112430Sphk setsignal(SIGTTOU); 158112430Sphk setsignal(SIGTTIN); 159112430Sphk setpgid(0, rootpid); 160112430Sphk#ifdef OLD_TTY_DRIVER 161112430Sphk ioctl(2, TIOCSPGRP, (char *)&rootpid); 162112430Sphk#else 163112430Sphk tcsetpgrp(2, rootpid); 164112430Sphk#endif 165112430Sphk } else { /* turning job control off */ 166112430Sphk setpgid(0, initialpgrp); 167144290Sjeff#ifdef OLD_TTY_DRIVER 168112430Sphk ioctl(2, TIOCSPGRP, (char *)&initialpgrp); 169112430Sphk#else 170112430Sphk tcsetpgrp(2, initialpgrp); 171112430Sphk#endif 172112430Sphk setsignal(SIGTSTP); 173122861Srwatson setsignal(SIGTTOU); 174122861Srwatson setsignal(SIGTTIN); 175122861Srwatson } 176122861Srwatson jobctl = on; 177122861Srwatson} 178112430Sphk#endif 179112430Sphk 180112430Sphk 181112430Sphk#ifdef mkinit 182112430SphkINCLUDE <sys/types.h> 183112430SphkINCLUDE <stdlib.h> 184112430Sphk 185112430SphkSHELLPROC { 186112430Sphk backgndpid = -1; 187112430Sphk#if JOBS 188145006Sjeff jobctl = 0; 189112430Sphk#endif 190112430Sphk} 191112430Sphk 192112430Sphk#endif 193112430Sphk 194112430Sphk 195112430Sphk 196112430Sphk#if JOBS 197112430Sphkint 198112430Sphkfgcmd(argc, argv) 199112430Sphk int argc __unused; 200112430Sphk char **argv; 201112430Sphk{ 202112430Sphk struct job *jp; 203112430Sphk int pgrp; 204112430Sphk int status; 205112430Sphk 206112430Sphk jp = getjob(argv[1]); 207112430Sphk if (jp->jobctl == 0) 208112430Sphk error("job not created under job control"); 209112430Sphk pgrp = jp->ps[0].pid; 210112430Sphk#ifdef OLD_TTY_DRIVER 211112430Sphk ioctl(2, TIOCSPGRP, (char *)&pgrp); 212112430Sphk#else 213112430Sphk tcsetpgrp(2, pgrp); 214112430Sphk#endif 215112430Sphk restartjob(jp); 216112430Sphk INTOFF; 217112430Sphk status = waitforjob(jp, (int *)NULL); 218112430Sphk INTON; 219112430Sphk return status; 220112430Sphk} 221112430Sphk 222112430Sphk 223112430Sphkint 224112430Sphkbgcmd(argc, argv) 225112430Sphk int argc; 226112430Sphk char **argv; 227112430Sphk{ 228112430Sphk struct job *jp; 229112430Sphk 230112430Sphk do { 231112430Sphk jp = getjob(*++argv); 232112430Sphk if (jp->jobctl == 0) 233112430Sphk error("job not created under job control"); 234112430Sphk restartjob(jp); 235112430Sphk } while (--argc > 1); 236112430Sphk return 0; 237112430Sphk} 238112430Sphk 239112430Sphk 240112430SphkSTATIC void 241112430Sphkrestartjob(jp) 242112430Sphk struct job *jp; 243112430Sphk{ 244112430Sphk struct procstat *ps; 245112430Sphk int i; 246112430Sphk 247112430Sphk if (jp->state == JOBDONE) 248112430Sphk return; 249112430Sphk INTOFF; 250112430Sphk killpg(jp->ps[0].pid, SIGCONT); 251112430Sphk for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 252112430Sphk if (WIFSTOPPED(ps->status)) { 253112430Sphk ps->status = -1; 254112430Sphk jp->state = 0; 255112430Sphk } 256112430Sphk } 257112430Sphk INTON; 258112430Sphk} 259112430Sphk#endif 260112430Sphk 261112430Sphk 262112430Sphkint 263112430Sphkjobscmd(argc, argv) 264112430Sphk int argc __unused; 265112430Sphk char **argv __unused; 266112430Sphk{ 267112430Sphk showjobs(0); 268112430Sphk return 0; 269112430Sphk} 270112430Sphk 271112430Sphk 272112430Sphk/* 273112430Sphk * Print a list of jobs. If "change" is nonzero, only print jobs whose 274112430Sphk * statuses have changed since the last call to showjobs. 275112430Sphk * 276112430Sphk * If the shell is interrupted in the process of creating a job, the 277112430Sphk * result may be a job structure containing zero processes. Such structures 278112430Sphk * will be freed here. 279112430Sphk */ 280112430Sphk 281112430Sphkvoid 282112430Sphkshowjobs(change) 283112430Sphk int change; 284145006Sjeff{ 285112430Sphk int jobno; 286112430Sphk int procno; 287112430Sphk int i; 288112430Sphk struct job *jp; 289112430Sphk struct procstat *ps; 290112430Sphk int col; 291112430Sphk char s[64]; 292112430Sphk 293112430Sphk TRACE(("showjobs(%d) called\n", change)); 294112430Sphk while (dowait(0, (struct job *)NULL) > 0); 295112430Sphk for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 296112430Sphk if (! jp->used) 297112430Sphk continue; 298112430Sphk if (jp->nprocs == 0) { 299112430Sphk freejob(jp); 300112430Sphk continue; 301112430Sphk } 302112430Sphk if (change && ! jp->changed) 303112430Sphk continue; 304112430Sphk procno = jp->nprocs; 305112430Sphk for (ps = jp->ps ; ; ps++) { /* for each process */ 306112430Sphk if (ps == jp->ps) 307112430Sphk fmtstr(s, 64, "[%d] %d ", jobno, ps->pid); 308112430Sphk else 309112430Sphk fmtstr(s, 64, " %d ", ps->pid); 310112430Sphk out1str(s); 311112430Sphk col = strlen(s); 312112430Sphk s[0] = '\0'; 313112430Sphk if (ps->status == -1) { 314112430Sphk /* don't print anything */ 315112430Sphk } else if (WIFEXITED(ps->status)) { 316112430Sphk fmtstr(s, 64, "Exit %d", WEXITSTATUS(ps->status)); 317112430Sphk } else { 318112430Sphk#if JOBS 319112430Sphk if (WIFSTOPPED(ps->status)) 320112430Sphk i = WSTOPSIG(ps->status); 321112430Sphk else 322112430Sphk#endif 323112430Sphk i = WTERMSIG(ps->status); 324112430Sphk if ((i & 0x7F) < NSIG && sys_siglist[i & 0x7F]) 325112430Sphk scopy(sys_siglist[i & 0x7F], s); 326112430Sphk else 327112430Sphk fmtstr(s, 64, "Signal %d", i & 0x7F); 328112430Sphk if (WCOREDUMP(ps->status)) 329112430Sphk strcat(s, " (core dumped)"); 330112430Sphk } 331112430Sphk out1str(s); 332112430Sphk col += strlen(s); 333112430Sphk do { 334112430Sphk out1c(' '); 335112430Sphk col++; 336112430Sphk } while (col < 30); 337112430Sphk out1str(ps->cmd); 338112430Sphk out1c('\n'); 339112430Sphk if (--procno <= 0) 340112430Sphk break; 341112430Sphk } 342112430Sphk jp->changed = 0; 343112430Sphk if (jp->state == JOBDONE) { 344112430Sphk freejob(jp); 345112430Sphk } 346112430Sphk } 347112430Sphk} 348112430Sphk 349112430Sphk 350112430Sphk/* 351112430Sphk * Mark a job structure as unused. 352112430Sphk */ 353112430Sphk 354112430SphkSTATIC void 355112430Sphkfreejob(jp) 356112430Sphk struct job *jp; 357112430Sphk { 358112430Sphk struct procstat *ps; 359112430Sphk int i; 360112430Sphk 361112430Sphk INTOFF; 362112430Sphk for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 363112430Sphk if (ps->cmd != nullstr) 364112430Sphk ckfree(ps->cmd); 365112430Sphk } 366112430Sphk if (jp->ps != &jp->ps0) 367112430Sphk ckfree(jp->ps); 368112430Sphk jp->used = 0; 369112430Sphk#if JOBS 370112430Sphk if (curjob == jp - jobtab + 1) 371112430Sphk curjob = 0; 372112430Sphk#endif 373112430Sphk INTON; 374112430Sphk} 375112430Sphk 376112430Sphk 377112430Sphk 378112430Sphkint 379112430Sphkwaitcmd(argc, argv) 380112430Sphk int argc; 381112430Sphk char **argv; 382112430Sphk{ 383112430Sphk struct job *job; 384112430Sphk int status, retval; 385112430Sphk struct job *jp; 386112430Sphk 387112430Sphk if (argc > 1) { 388112430Sphk job = getjob(argv[1]); 389112430Sphk } else { 390112430Sphk job = NULL; 391112430Sphk } 392112430Sphk 393112430Sphk /* 394112430Sphk * Loop until a process is terminated or stopped, or a SIGINT is 395112430Sphk * received. 396112430Sphk */ 397112430Sphk 398112430Sphk in_waitcmd++; 399112430Sphk do { 400112430Sphk if (job != NULL) { 401112430Sphk if (job->state) { 402112430Sphk status = job->ps[job->nprocs - 1].status; 403112430Sphk if (WIFEXITED(status)) 404112430Sphk retval = WEXITSTATUS(status); 405112430Sphk#if JOBS 406112430Sphk else if (WIFSTOPPED(status)) 407112430Sphk retval = WSTOPSIG(status) + 128; 408112430Sphk#endif 409112430Sphk else 410112430Sphk retval = WTERMSIG(status) + 128; 411112430Sphk if (! iflag) 412112430Sphk freejob(job); 413112430Sphk in_waitcmd--; 414112430Sphk return retval; 415112430Sphk } 416112430Sphk } else { 417112430Sphk for (jp = jobtab ; ; jp++) { 418112430Sphk if (jp >= jobtab + njobs) { /* no running procs */ 419112430Sphk in_waitcmd--; 420112430Sphk return 0; 421112430Sphk } 42282518Sgallatin if (jp->used && jp->state == 0) 42382518Sgallatin break; 42482518Sgallatin } 425112430Sphk } 42682518Sgallatin } while (dowait(1, (struct job *)NULL) != -1); 42782518Sgallatin in_waitcmd--; 42882518Sgallatin 42983366Sjulian return 0; 43082518Sgallatin} 431112430Sphk 432112430Sphk 433112430Sphk 434112430Sphkint 435112430Sphkjobidcmd(argc, argv) 436112430Sphk int argc __unused; 437112430Sphk char **argv; 438112430Sphk{ 439112430Sphk struct job *jp; 440112430Sphk int i; 441112430Sphk 442112430Sphk jp = getjob(argv[1]); 443112430Sphk for (i = 0 ; i < jp->nprocs ; ) { 444112430Sphk out1fmt("%d", jp->ps[i].pid); 445112430Sphk out1c(++i < jp->nprocs? ' ' : '\n'); 446112430Sphk } 447112430Sphk return 0; 448112430Sphk} 449112430Sphk 450112430Sphk 451112430Sphk 452112430Sphk/* 453112430Sphk * Convert a job name to a job structure. 454112430Sphk */ 455112430Sphk 456112430SphkSTATIC struct job * 457112430Sphkgetjob(name) 458112430Sphk char *name; 459112430Sphk { 460112430Sphk int jobno; 461112430Sphk struct job *jp; 462112430Sphk int pid; 463112430Sphk int i; 464112430Sphk 465112430Sphk if (name == NULL) { 466112430Sphk#if JOBS 467112430Sphkcurrentjob: 468147854Sjhb if ((jobno = curjob) == 0 || jobtab[jobno - 1].used == 0) 469112430Sphk error("No current job"); 470112430Sphk return &jobtab[jobno - 1]; 471147854Sjhb#else 472112430Sphk error("No current job"); 473112430Sphk#endif 474112430Sphk } else if (name[0] == '%') { 475112430Sphk if (is_digit(name[1])) { 476112430Sphk jobno = number(name + 1); 477112430Sphk if (jobno > 0 && jobno <= njobs 478112430Sphk && jobtab[jobno - 1].used != 0) 479112430Sphk return &jobtab[jobno - 1]; 480112430Sphk#if JOBS 481112430Sphk } else if (name[1] == '%' && name[2] == '\0') { 482112430Sphk goto currentjob; 48382518Sgallatin#endif 48482518Sgallatin } else { 485 struct job *found = NULL; 486 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 487 if (jp->used && jp->nprocs > 0 488 && prefix(name + 1, jp->ps[0].cmd)) { 489 if (found) 490 error("%s: ambiguous", name); 491 found = jp; 492 } 493 } 494 if (found) 495 return found; 496 } 497 } else if (is_number(name)) { 498 pid = number(name); 499 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 500 if (jp->used && jp->nprocs > 0 501 && jp->ps[jp->nprocs - 1].pid == pid) 502 return jp; 503 } 504 } 505 error("No such job: %s", name); 506 /*NOTREACHED*/ 507 return NULL; 508} 509 510 511 512/* 513 * Return a new job structure, 514 */ 515 516struct job * 517makejob(node, nprocs) 518 union node *node __unused; 519 int nprocs; 520{ 521 int i; 522 struct job *jp; 523 524 for (i = njobs, jp = jobtab ; ; jp++) { 525 if (--i < 0) { 526 INTOFF; 527 if (njobs == 0) { 528 jobtab = ckmalloc(4 * sizeof jobtab[0]); 529 } else { 530 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 531 memcpy(jp, jobtab, njobs * sizeof jp[0]); 532 /* Relocate `ps' pointers */ 533 for (i = 0; i < njobs; i++) 534 if (jp[i].ps == &jobtab[i].ps0) 535 jp[i].ps = &jp[i].ps0; 536 ckfree(jobtab); 537 jobtab = jp; 538 } 539 jp = jobtab + njobs; 540 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 541 INTON; 542 break; 543 } 544 if (jp->used == 0) 545 break; 546 } 547 INTOFF; 548 jp->state = 0; 549 jp->used = 1; 550 jp->changed = 0; 551 jp->nprocs = 0; 552#if JOBS 553 jp->jobctl = jobctl; 554#endif 555 if (nprocs > 1) { 556 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 557 } else { 558 jp->ps = &jp->ps0; 559 } 560 INTON; 561 TRACE(("makejob(0x%lx, %d) returns %%%d\n", (long)node, nprocs, 562 jp - jobtab + 1)); 563 return jp; 564} 565 566 567/* 568 * Fork of a subshell. If we are doing job control, give the subshell its 569 * own process group. Jp is a job structure that the job is to be added to. 570 * N is the command that will be evaluated by the child. Both jp and n may 571 * be NULL. The mode parameter can be one of the following: 572 * FORK_FG - Fork off a foreground process. 573 * FORK_BG - Fork off a background process. 574 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 575 * process group even if job control is on. 576 * 577 * When job control is turned off, background processes have their standard 578 * input redirected to /dev/null (except for the second and later processes 579 * in a pipeline). 580 */ 581 582int 583forkshell(jp, n, mode) 584 union node *n; 585 struct job *jp; 586 int mode; 587{ 588 int pid; 589 int pgrp; 590 591 TRACE(("forkshell(%%%d, 0x%lx, %d) called\n", jp - jobtab, (long)n, 592 mode)); 593 INTOFF; 594 pid = fork(); 595 if (pid == -1) { 596 TRACE(("Fork failed, errno=%d\n", errno)); 597 INTON; 598 error("Cannot fork: %s", strerror(errno)); 599 } 600 if (pid == 0) { 601 struct job *p; 602 int wasroot; 603 int i; 604 605 TRACE(("Child shell %d\n", getpid())); 606 wasroot = rootshell; 607 rootshell = 0; 608 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 609 if (p->used) 610 freejob(p); 611 closescript(); 612 INTON; 613 clear_traps(); 614#if JOBS 615 jobctl = 0; /* do job control only in root shell */ 616 if (wasroot && mode != FORK_NOJOB && mflag) { 617 if (jp == NULL || jp->nprocs == 0) 618 pgrp = getpid(); 619 else 620 pgrp = jp->ps[0].pid; 621 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 622 /*** this causes superfluous TIOCSPGRPS ***/ 623#ifdef OLD_TTY_DRIVER 624 if (ioctl(2, TIOCSPGRP, (char *)&pgrp) < 0) 625 error("TIOCSPGRP failed, errno=%d", errno); 626#else 627 if (tcsetpgrp(2, pgrp) < 0) 628 error("tcsetpgrp failed, errno=%d", errno); 629#endif 630 } 631 setsignal(SIGTSTP); 632 setsignal(SIGTTOU); 633 } else if (mode == FORK_BG) { 634 ignoresig(SIGINT); 635 ignoresig(SIGQUIT); 636 if ((jp == NULL || jp->nprocs == 0) && 637 ! fd0_redirected_p ()) { 638 close(0); 639 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 640 error("Can't open %s: %s", 641 _PATH_DEVNULL, strerror(errno)); 642 } 643 } 644#else 645 if (mode == FORK_BG) { 646 ignoresig(SIGINT); 647 ignoresig(SIGQUIT); 648 if ((jp == NULL || jp->nprocs == 0) && 649 ! fd0_redirected_p ()) { 650 close(0); 651 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 652 error("Can't open %s: %s", 653 _PATH_DEVNULL, strerror(errno)); 654 } 655 } 656#endif 657 if (wasroot && iflag) { 658 setsignal(SIGINT); 659 setsignal(SIGQUIT); 660 setsignal(SIGTERM); 661 } 662 return pid; 663 } 664 if (rootshell && mode != FORK_NOJOB && mflag) { 665 if (jp == NULL || jp->nprocs == 0) 666 pgrp = pid; 667 else 668 pgrp = jp->ps[0].pid; 669 setpgid(pid, pgrp); 670 } 671 if (mode == FORK_BG) 672 backgndpid = pid; /* set $! */ 673 if (jp) { 674 struct procstat *ps = &jp->ps[jp->nprocs++]; 675 ps->pid = pid; 676 ps->status = -1; 677 ps->cmd = nullstr; 678 if (iflag && rootshell && n) 679 ps->cmd = commandtext(n); 680 } 681 INTON; 682 TRACE(("In parent shell: child = %d\n", pid)); 683 return pid; 684} 685 686 687 688/* 689 * Wait for job to finish. 690 * 691 * Under job control we have the problem that while a child process is 692 * running interrupts generated by the user are sent to the child but not 693 * to the shell. This means that an infinite loop started by an inter- 694 * active user may be hard to kill. With job control turned off, an 695 * interactive user may place an interactive program inside a loop. If 696 * the interactive program catches interrupts, the user doesn't want 697 * these interrupts to also abort the loop. The approach we take here 698 * is to have the shell ignore interrupt signals while waiting for a 699 * foreground process to terminate, and then send itself an interrupt 700 * signal if the child process was terminated by an interrupt signal. 701 * Unfortunately, some programs want to do a bit of cleanup and then 702 * exit on interrupt; unless these processes terminate themselves by 703 * sending a signal to themselves (instead of calling exit) they will 704 * confuse this approach. 705 */ 706 707int 708waitforjob(jp, origstatus) 709 struct job *jp; 710 int *origstatus; 711{ 712#if JOBS 713 int mypgrp = getpgrp(); 714#endif 715 int status; 716 int st; 717 718 INTOFF; 719 TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1)); 720 while (jp->state == 0) 721 if (dowait(1, jp) == -1) 722 dotrap(); 723#if JOBS 724 if (jp->jobctl) { 725#ifdef OLD_TTY_DRIVER 726 if (ioctl(2, TIOCSPGRP, (char *)&mypgrp) < 0) 727 error("TIOCSPGRP failed, errno=%d\n", errno); 728#else 729 if (tcsetpgrp(2, mypgrp) < 0) 730 error("tcsetpgrp failed, errno=%d\n", errno); 731#endif 732 } 733 if (jp->state == JOBSTOPPED) 734 curjob = jp - jobtab + 1; 735#endif 736 status = jp->ps[jp->nprocs - 1].status; 737 if (origstatus != NULL) 738 *origstatus = status; 739 /* convert to 8 bits */ 740 if (WIFEXITED(status)) 741 st = WEXITSTATUS(status); 742#if JOBS 743 else if (WIFSTOPPED(status)) 744 st = WSTOPSIG(status) + 128; 745#endif 746 else 747 st = WTERMSIG(status) + 128; 748 if (! JOBS || jp->state == JOBDONE) 749 freejob(jp); 750 if (int_pending()) { 751 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 752 kill(getpid(), SIGINT); 753 else 754 CLEAR_PENDING_INT; 755 } 756 INTON; 757 return st; 758} 759 760 761 762/* 763 * Wait for a process to terminate. 764 */ 765 766STATIC int 767dowait(block, job) 768 int block; 769 struct job *job; 770{ 771 int pid; 772 int status; 773 struct procstat *sp; 774 struct job *jp; 775 struct job *thisjob; 776 int done; 777 int stopped; 778 int core; 779 int sig; 780 781 in_dowait++; 782 TRACE(("dowait(%d) called\n", block)); 783 do { 784 pid = waitproc(block, &status); 785 TRACE(("wait returns %d, status=%d\n", pid, status)); 786 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 787 (WIFSTOPPED(status) && !iflag)); 788 in_dowait--; 789 if (breakwaitcmd != 0) { 790 breakwaitcmd = 0; 791 return -1; 792 } 793 if (pid <= 0) 794 return pid; 795 INTOFF; 796 thisjob = NULL; 797 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 798 if (jp->used) { 799 done = 1; 800 stopped = 1; 801 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 802 if (sp->pid == -1) 803 continue; 804 if (sp->pid == pid) { 805 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 806 pid, sp->status, status)); 807 sp->status = status; 808 thisjob = jp; 809 } 810 if (sp->status == -1) 811 stopped = 0; 812 else if (WIFSTOPPED(sp->status)) 813 done = 0; 814 } 815 if (stopped) { /* stopped or done */ 816 int state = done? JOBDONE : JOBSTOPPED; 817 if (jp->state != state) { 818 TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 819 jp->state = state; 820#if JOBS 821 if (done && curjob == jp - jobtab + 1) 822 curjob = 0; /* no current job */ 823#endif 824 } 825 } 826 } 827 } 828 INTON; 829 if (! rootshell || ! iflag || (job && thisjob == job)) { 830 core = WCOREDUMP(status); 831#if JOBS 832 if (WIFSTOPPED(status)) 833 sig = WSTOPSIG(status); 834 else 835#endif 836 if (WIFEXITED(status)) 837 sig = 0; 838 else 839 sig = WTERMSIG(status); 840 841 if (sig != 0 && sig != SIGINT && sig != SIGPIPE) { 842 if (thisjob != job) 843 outfmt(out2, "%d: ", pid); 844#if JOBS 845 if (sig == SIGTSTP && rootshell && iflag) 846 outfmt(out2, "%%%d ", job - jobtab + 1); 847#endif 848 if (sig < NSIG && sys_siglist[sig]) 849 out2str(sys_siglist[sig]); 850 else 851 outfmt(out2, "Signal %d", sig); 852 if (core) 853 out2str(" - core dumped"); 854 out2c('\n'); 855 flushout(&errout); 856 } else { 857 TRACE(("Not printing status: status=%d, sig=%d\n", 858 status, sig)); 859 } 860 } else { 861 TRACE(("Not printing status, rootshell=%d, job=0x%x\n", rootshell, job)); 862 if (thisjob) 863 thisjob->changed = 1; 864 } 865 return pid; 866} 867 868 869 870/* 871 * Do a wait system call. If job control is compiled in, we accept 872 * stopped processes. If block is zero, we return a value of zero 873 * rather than blocking. 874 * 875 * System V doesn't have a non-blocking wait system call. It does 876 * have a SIGCLD signal that is sent to a process when one of it's 877 * children dies. The obvious way to use SIGCLD would be to install 878 * a handler for SIGCLD which simply bumped a counter when a SIGCLD 879 * was received, and have waitproc bump another counter when it got 880 * the status of a process. Waitproc would then know that a wait 881 * system call would not block if the two counters were different. 882 * This approach doesn't work because if a process has children that 883 * have not been waited for, System V will send it a SIGCLD when it 884 * installs a signal handler for SIGCLD. What this means is that when 885 * a child exits, the shell will be sent SIGCLD signals continuously 886 * until is runs out of stack space, unless it does a wait call before 887 * restoring the signal handler. The code below takes advantage of 888 * this (mis)feature by installing a signal handler for SIGCLD and 889 * then checking to see whether it was called. If there are any 890 * children to be waited for, it will be. 891 * 892 * If neither SYSV nor BSD is defined, we don't implement nonblocking 893 * waits at all. In this case, the user will not be informed when 894 * a background process until the next time she runs a real program 895 * (as opposed to running a builtin command or just typing return), 896 * and the jobs command may give out of date information. 897 */ 898 899#ifdef SYSV 900STATIC sig_atomic_t gotsigchild; 901 902STATIC int onsigchild() { 903 gotsigchild = 1; 904} 905#endif 906 907 908STATIC int 909waitproc(block, status) 910 int block; 911 int *status; 912{ 913#ifdef BSD 914 int flags; 915 916#if JOBS 917 flags = WUNTRACED; 918#else 919 flags = 0; 920#endif 921 if (block == 0) 922 flags |= WNOHANG; 923 return wait3(status, flags, (struct rusage *)NULL); 924#else 925#ifdef SYSV 926 int (*save)(); 927 928 if (block == 0) { 929 gotsigchild = 0; 930 save = signal(SIGCLD, onsigchild); 931 signal(SIGCLD, save); 932 if (gotsigchild == 0) 933 return 0; 934 } 935 return wait(status); 936#else 937 if (block == 0) 938 return 0; 939 return wait(status); 940#endif 941#endif 942} 943 944/* 945 * return 1 if there are stopped jobs, otherwise 0 946 */ 947int job_warning = 0; 948int 949stoppedjobs() 950{ 951 int jobno; 952 struct job *jp; 953 954 if (job_warning) 955 return (0); 956 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 957 if (jp->used == 0) 958 continue; 959 if (jp->state == JOBSTOPPED) { 960 out2str("You have stopped jobs.\n"); 961 job_warning = 2; 962 return (1); 963 } 964 } 965 966 return (0); 967} 968 969/* 970 * Return a string identifying a command (to be printed by the 971 * jobs command. 972 */ 973 974STATIC char *cmdnextc; 975STATIC int cmdnleft; 976#define MAXCMDTEXT 200 977 978char * 979commandtext(n) 980 union node *n; 981 { 982 char *name; 983 984 cmdnextc = name = ckmalloc(MAXCMDTEXT); 985 cmdnleft = MAXCMDTEXT - 4; 986 cmdtxt(n); 987 *cmdnextc = '\0'; 988 return name; 989} 990 991 992STATIC void 993cmdtxt(n) 994 union node *n; 995 { 996 union node *np; 997 struct nodelist *lp; 998 char *p; 999 int i; 1000 char s[2]; 1001 1002 if (n == NULL) 1003 return; 1004 switch (n->type) { 1005 case NSEMI: 1006 cmdtxt(n->nbinary.ch1); 1007 cmdputs("; "); 1008 cmdtxt(n->nbinary.ch2); 1009 break; 1010 case NAND: 1011 cmdtxt(n->nbinary.ch1); 1012 cmdputs(" && "); 1013 cmdtxt(n->nbinary.ch2); 1014 break; 1015 case NOR: 1016 cmdtxt(n->nbinary.ch1); 1017 cmdputs(" || "); 1018 cmdtxt(n->nbinary.ch2); 1019 break; 1020 case NPIPE: 1021 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1022 cmdtxt(lp->n); 1023 if (lp->next) 1024 cmdputs(" | "); 1025 } 1026 break; 1027 case NSUBSHELL: 1028 cmdputs("("); 1029 cmdtxt(n->nredir.n); 1030 cmdputs(")"); 1031 break; 1032 case NREDIR: 1033 case NBACKGND: 1034 cmdtxt(n->nredir.n); 1035 break; 1036 case NIF: 1037 cmdputs("if "); 1038 cmdtxt(n->nif.test); 1039 cmdputs("; then "); 1040 cmdtxt(n->nif.ifpart); 1041 cmdputs("..."); 1042 break; 1043 case NWHILE: 1044 cmdputs("while "); 1045 goto until; 1046 case NUNTIL: 1047 cmdputs("until "); 1048until: 1049 cmdtxt(n->nbinary.ch1); 1050 cmdputs("; do "); 1051 cmdtxt(n->nbinary.ch2); 1052 cmdputs("; done"); 1053 break; 1054 case NFOR: 1055 cmdputs("for "); 1056 cmdputs(n->nfor.var); 1057 cmdputs(" in ..."); 1058 break; 1059 case NCASE: 1060 cmdputs("case "); 1061 cmdputs(n->ncase.expr->narg.text); 1062 cmdputs(" in ..."); 1063 break; 1064 case NDEFUN: 1065 cmdputs(n->narg.text); 1066 cmdputs("() ..."); 1067 break; 1068 case NCMD: 1069 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1070 cmdtxt(np); 1071 if (np->narg.next) 1072 cmdputs(" "); 1073 } 1074 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1075 cmdputs(" "); 1076 cmdtxt(np); 1077 } 1078 break; 1079 case NARG: 1080 cmdputs(n->narg.text); 1081 break; 1082 case NTO: 1083 p = ">"; i = 1; goto redir; 1084 case NAPPEND: 1085 p = ">>"; i = 1; goto redir; 1086 case NTOFD: 1087 p = ">&"; i = 1; goto redir; 1088 case NFROM: 1089 p = "<"; i = 0; goto redir; 1090 case NFROMTO: 1091 p = "<>"; i = 0; goto redir; 1092 case NFROMFD: 1093 p = "<&"; i = 0; goto redir; 1094redir: 1095 if (n->nfile.fd != i) { 1096 s[0] = n->nfile.fd + '0'; 1097 s[1] = '\0'; 1098 cmdputs(s); 1099 } 1100 cmdputs(p); 1101 if (n->type == NTOFD || n->type == NFROMFD) { 1102 s[0] = n->ndup.dupfd + '0'; 1103 s[1] = '\0'; 1104 cmdputs(s); 1105 } else { 1106 cmdtxt(n->nfile.fname); 1107 } 1108 break; 1109 case NHERE: 1110 case NXHERE: 1111 cmdputs("<<..."); 1112 break; 1113 default: 1114 cmdputs("???"); 1115 break; 1116 } 1117} 1118 1119 1120 1121STATIC void 1122cmdputs(s) 1123 char *s; 1124 { 1125 char *p, *q; 1126 char c; 1127 int subtype = 0; 1128 1129 if (cmdnleft <= 0) 1130 return; 1131 p = s; 1132 q = cmdnextc; 1133 while ((c = *p++) != '\0') { 1134 if (c == CTLESC) 1135 *q++ = *p++; 1136 else if (c == CTLVAR) { 1137 *q++ = '$'; 1138 if (--cmdnleft > 0) 1139 *q++ = '{'; 1140 subtype = *p++; 1141 } else if (c == '=' && subtype != 0) { 1142 *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL]; 1143 subtype = 0; 1144 } else if (c == CTLENDVAR) { 1145 *q++ = '}'; 1146 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) 1147 cmdnleft++; /* ignore it */ 1148 else 1149 *q++ = c; 1150 if (--cmdnleft <= 0) { 1151 *q++ = '.'; 1152 *q++ = '.'; 1153 *q++ = '.'; 1154 break; 1155 } 1156 } 1157 cmdnextc = q; 1158} 1159