jobs.c revision 3044
1344957Smarcel/*- 2344957Smarcel * Copyright (c) 1991, 1993 3344957Smarcel * The Regents of the University of California. All rights reserved. 4344957Smarcel * 5344957Smarcel * This code is derived from software contributed to Berkeley by 6344957Smarcel * Kenneth Almquist. 7344957Smarcel * 8344957Smarcel * Redistribution and use in source and binary forms, with or without 9344957Smarcel * modification, are permitted provided that the following conditions 10344957Smarcel * are met: 11344957Smarcel * 1. Redistributions of source code must retain the above copyright 12344957Smarcel * notice, this list of conditions and the following disclaimer. 13344957Smarcel * 2. Redistributions in binary form must reproduce the above copyright 14344957Smarcel * notice, this list of conditions and the following disclaimer in the 15344957Smarcel * documentation and/or other materials provided with the distribution. 16344957Smarcel * 3. All advertising materials mentioning features or use of this software 17344957Smarcel * must display the following acknowledgement: 18344957Smarcel * This product includes software developed by the University of 19344957Smarcel * California, Berkeley and its contributors. 20344957Smarcel * 4. Neither the name of the University nor the names of its contributors 21344957Smarcel * may be used to endorse or promote products derived from this software 22344957Smarcel * without specific prior written permission. 23344957Smarcel * 24344957Smarcel * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25344957Smarcel * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26344957Smarcel * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27344957Smarcel * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28344957Smarcel * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29344957Smarcel * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30344957Smarcel * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31344957Smarcel * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32344957Smarcel * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33344957Smarcel * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34344957Smarcel * SUCH DAMAGE. 35344957Smarcel * 36344957Smarcel * $Id$ 37344957Smarcel */ 38344957Smarcel 39344957Smarcel#ifndef lint 40344957Smarcelstatic char sccsid[] = "@(#)jobs.c 8.1 (Berkeley) 5/31/93"; 41344957Smarcel#endif /* not lint */ 42344957Smarcel 43344957Smarcel#include "shell.h" 44344957Smarcel#if JOBS 45344957Smarcel#include "sgtty.h" 46344957Smarcel#undef CEOF /* syntax.h redefines this */ 47344957Smarcel#endif 48344957Smarcel#include "main.h" 49344957Smarcel#include "parser.h" 50344957Smarcel#include "nodes.h" 51344957Smarcel#include "jobs.h" 52344957Smarcel#include "options.h" 53344957Smarcel#include "trap.h" 54344957Smarcel#include "signames.h" 55344957Smarcel#include "syntax.h" 56344957Smarcel#include "input.h" 57344957Smarcel#include "output.h" 58344957Smarcel#include "memalloc.h" 59344957Smarcel#include "error.h" 60344957Smarcel#include "mystring.h" 61344957Smarcel#include <fcntl.h> 62344957Smarcel#include <signal.h> 63344957Smarcel#include <errno.h> 64344957Smarcel#ifdef BSD 65344957Smarcel#include <sys/types.h> 66344957Smarcel#include <sys/wait.h> 67344957Smarcel#include <sys/time.h> 68344957Smarcel#include <sys/resource.h> 69344957Smarcel#endif 70344957Smarcel 71344957Smarcel 72344957Smarcel 73344957Smarcelstruct job *jobtab; /* array of jobs */ 74344957Smarcelint njobs; /* size of array */ 75344957SmarcelMKINIT short backgndpid = -1; /* pid of last background process */ 76344957Smarcel#if JOBS 77344957Smarcelint initialpgrp; /* pgrp of shell on invocation */ 78344957Smarcelshort curjob; /* current job */ 79344957Smarcel#endif 80344957Smarcel 81344957Smarcel#ifdef __STDC__ 82344957SmarcelSTATIC void restartjob(struct job *); 83344957SmarcelSTATIC struct job *getjob(char *); 84344957SmarcelSTATIC void freejob(struct job *); 85344957SmarcelSTATIC int procrunning(int); 86344957SmarcelSTATIC int dowait(int, struct job *); 87344957SmarcelSTATIC int waitproc(int, int *); 88344957Smarcel#else 89344957SmarcelSTATIC void restartjob(); 90344957SmarcelSTATIC struct job *getjob(); 91344957SmarcelSTATIC void freejob(); 92344957SmarcelSTATIC int procrunning(); 93344957SmarcelSTATIC int dowait(); 94344957SmarcelSTATIC int waitproc(); 95344957Smarcel#endif 96344957Smarcel 97344957Smarcel 98344957Smarcel 99344957Smarcel/* 100344957Smarcel * Turn job control on and off. 101344957Smarcel * 102344957Smarcel * Note: This code assumes that the third arg to ioctl is a character 103344957Smarcel * pointer, which is true on Berkeley systems but not System V. Since 104344957Smarcel * System V doesn't have job control yet, this isn't a problem now. 105344957Smarcel */ 106344957Smarcel 107344957SmarcelMKINIT int jobctl; 108344957Smarcel 109344957Smarcelvoid 110344957Smarcelsetjobctl(on) { 111344957Smarcel#ifdef OLD_TTY_DRIVER 112344957Smarcel int ldisc; 113344957Smarcel#endif 114344957Smarcel 115344957Smarcel if (on == jobctl || rootshell == 0) 116344957Smarcel return; 117344957Smarcel if (on) { 118344957Smarcel do { /* while we are in the background */ 119344957Smarcel if (ioctl(2, TIOCGPGRP, (char *)&initialpgrp) < 0) { 120344957Smarcel out2str("sh: can't access tty; job control turned off\n"); 121344957Smarcel mflag = 0; 122344957Smarcel return; 123344957Smarcel } 124344957Smarcel if (initialpgrp == -1) 125344957Smarcel initialpgrp = getpgrp(0); 126344957Smarcel else if (initialpgrp != getpgrp(0)) { 127344957Smarcel killpg(initialpgrp, SIGTTIN); 128344957Smarcel continue; 129344957Smarcel } 130344957Smarcel } while (0); 131344957Smarcel#ifdef OLD_TTY_DRIVER 132344957Smarcel if (ioctl(2, TIOCGETD, (char *)&ldisc) < 0 || ldisc != NTTYDISC) { 133344957Smarcel out2str("sh: need new tty driver to run job control; job control turned off\n"); 134344957Smarcel mflag = 0; 135344957Smarcel return; 136344957Smarcel } 137344957Smarcel#endif 138344957Smarcel setsignal(SIGTSTP); 139344957Smarcel setsignal(SIGTTOU); 140344957Smarcel setsignal(SIGTTIN); 141344957Smarcel setpgrp(0, rootpid); 142344957Smarcel ioctl(2, TIOCSPGRP, (char *)&rootpid); 143344957Smarcel } else { /* turning job control off */ 144344957Smarcel setpgrp(0, initialpgrp); 145344957Smarcel ioctl(2, TIOCSPGRP, (char *)&initialpgrp); 146344957Smarcel setsignal(SIGTSTP); 147344957Smarcel setsignal(SIGTTOU); 148344957Smarcel setsignal(SIGTTIN); 149344957Smarcel } 150344957Smarcel jobctl = on; 151344957Smarcel} 152344957Smarcel 153344957Smarcel 154344957Smarcel#ifdef mkinit 155344957Smarcel 156344957SmarcelSHELLPROC { 157344957Smarcel backgndpid = -1; 158344957Smarcel#if JOBS 159344957Smarcel jobctl = 0; 160344957Smarcel#endif 161344957Smarcel} 162344957Smarcel 163344957Smarcel#endif 164344957Smarcel 165344957Smarcel 166344957Smarcel 167344957Smarcel#if JOBS 168344957Smarcelfgcmd(argc, argv) char **argv; { 169344957Smarcel struct job *jp; 170344957Smarcel int pgrp; 171344957Smarcel int status; 172344957Smarcel 173344957Smarcel jp = getjob(argv[1]); 174344957Smarcel if (jp->jobctl == 0) 175344957Smarcel error("job not created under job control"); 176344957Smarcel pgrp = jp->ps[0].pid; 177344957Smarcel ioctl(2, TIOCSPGRP, (char *)&pgrp); 178344957Smarcel restartjob(jp); 179344957Smarcel INTOFF; 180344957Smarcel status = waitforjob(jp); 181344957Smarcel INTON; 182344957Smarcel return status; 183344957Smarcel} 184344957Smarcel 185344957Smarcel 186344957Smarcelbgcmd(argc, argv) char **argv; { 187344957Smarcel struct job *jp; 188344957Smarcel 189344957Smarcel do { 190344957Smarcel jp = getjob(*++argv); 191344957Smarcel if (jp->jobctl == 0) 192344957Smarcel error("job not created under job control"); 193344957Smarcel restartjob(jp); 194344957Smarcel } while (--argc > 1); 195344957Smarcel return 0; 196344957Smarcel} 197344957Smarcel 198344957Smarcel 199344957SmarcelSTATIC void 200344957Smarcelrestartjob(jp) 201344957Smarcel struct job *jp; 202344957Smarcel { 203344957Smarcel struct procstat *ps; 204344957Smarcel int i; 205344957Smarcel 206344957Smarcel if (jp->state == JOBDONE) 207344957Smarcel return; 208344957Smarcel INTOFF; 209344957Smarcel killpg(jp->ps[0].pid, SIGCONT); 210344957Smarcel for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 211344957Smarcel if ((ps->status & 0377) == 0177) { 212344957Smarcel ps->status = -1; 213344957Smarcel jp->state = 0; 214344957Smarcel } 215344957Smarcel } 216344957Smarcel INTON; 217344957Smarcel} 218344957Smarcel#endif 219344957Smarcel 220344957Smarcel 221344957Smarcelint 222344957Smarceljobscmd(argc, argv) char **argv; { 223344957Smarcel showjobs(0); 224344957Smarcel return 0; 225344957Smarcel} 226344957Smarcel 227344957Smarcel 228344957Smarcel/* 229344957Smarcel * Print a list of jobs. If "change" is nonzero, only print jobs whose 230344957Smarcel * statuses have changed since the last call to showjobs. 231344957Smarcel * 232344957Smarcel * If the shell is interrupted in the process of creating a job, the 233344957Smarcel * result may be a job structure containing zero processes. Such structures 234344957Smarcel * will be freed here. 235344957Smarcel */ 236344957Smarcel 237344957Smarcelvoid 238344957Smarcelshowjobs(change) { 239344957Smarcel int jobno; 240344957Smarcel int procno; 241344957Smarcel int i; 242344957Smarcel struct job *jp; 243344957Smarcel struct procstat *ps; 244344957Smarcel int col; 245344957Smarcel char s[64]; 246344957Smarcel 247344957Smarcel TRACE(("showjobs(%d) called\n", change)); 248344957Smarcel while (dowait(0, (struct job *)NULL) > 0); 249344957Smarcel for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 250344957Smarcel if (! jp->used) 251344957Smarcel continue; 252344957Smarcel if (jp->nprocs == 0) { 253344957Smarcel freejob(jp); 254344957Smarcel continue; 255344957Smarcel } 256344957Smarcel if (change && ! jp->changed) 257344957Smarcel continue; 258344957Smarcel procno = jp->nprocs; 259344957Smarcel for (ps = jp->ps ; ; ps++) { /* for each process */ 260344957Smarcel if (ps == jp->ps) 261344957Smarcel fmtstr(s, 64, "[%d] %d ", jobno, ps->pid); 262344957Smarcel else 263344957Smarcel fmtstr(s, 64, " %d ", ps->pid); 264344957Smarcel out1str(s); 265344957Smarcel col = strlen(s); 266344957Smarcel s[0] = '\0'; 267344957Smarcel if (ps->status == -1) { 268344957Smarcel /* don't print anything */ 269344957Smarcel } else if ((ps->status & 0xFF) == 0) { 270344957Smarcel fmtstr(s, 64, "Exit %d", ps->status >> 8); 271344957Smarcel } else { 272344957Smarcel i = ps->status; 273344957Smarcel#if JOBS 274344957Smarcel if ((i & 0xFF) == 0177) 275344957Smarcel i >>= 8; 276344957Smarcel#endif 277344957Smarcel if ((i & 0x7F) <= MAXSIG && sigmesg[i & 0x7F]) 278344957Smarcel scopy(sigmesg[i & 0x7F], s); 279344957Smarcel else 280344957Smarcel fmtstr(s, 64, "Signal %d", i & 0x7F); 281344957Smarcel if (i & 0x80) 282344957Smarcel strcat(s, " (core dumped)"); 283344957Smarcel } 284344957Smarcel out1str(s); 285344957Smarcel col += strlen(s); 286344957Smarcel do { 287344957Smarcel out1c(' '); 288344957Smarcel col++; 289344957Smarcel } while (col < 30); 290344957Smarcel out1str(ps->cmd); 291344957Smarcel out1c('\n'); 292344957Smarcel if (--procno <= 0) 293344957Smarcel break; 294344957Smarcel } 295344957Smarcel jp->changed = 0; 296344957Smarcel if (jp->state == JOBDONE) { 297344957Smarcel freejob(jp); 298344957Smarcel } 299344957Smarcel } 300344957Smarcel} 301344957Smarcel 302344957Smarcel 303344957Smarcel/* 304344957Smarcel * Mark a job structure as unused. 305344957Smarcel */ 306344957Smarcel 307344957SmarcelSTATIC void 308344957Smarcelfreejob(jp) 309344957Smarcel struct job *jp; 310344957Smarcel { 311344957Smarcel struct procstat *ps; 312344957Smarcel int i; 313344957Smarcel 314344957Smarcel INTOFF; 315344957Smarcel for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 316344957Smarcel if (ps->cmd != nullstr) 317344957Smarcel ckfree(ps->cmd); 318344957Smarcel } 319344957Smarcel if (jp->ps != &jp->ps0) 320344957Smarcel ckfree(jp->ps); 321344957Smarcel jp->used = 0; 322344957Smarcel#if JOBS 323344957Smarcel if (curjob == jp - jobtab + 1) 324344957Smarcel curjob = 0; 325344957Smarcel#endif 326344957Smarcel INTON; 327344957Smarcel} 328344957Smarcel 329344957Smarcel 330344957Smarcel 331344957Smarcelint 332344957Smarcelwaitcmd(argc, argv) char **argv; { 333344957Smarcel struct job *job; 334344957Smarcel int status; 335344957Smarcel struct job *jp; 336344957Smarcel 337344957Smarcel if (argc > 1) { 338344957Smarcel job = getjob(argv[1]); 339344957Smarcel } else { 340344957Smarcel job = NULL; 341344957Smarcel } 342344957Smarcel for (;;) { /* loop until process terminated or stopped */ 343344957Smarcel if (job != NULL) { 344344957Smarcel if (job->state) { 345344957Smarcel status = job->ps[job->nprocs - 1].status; 346344957Smarcel if ((status & 0xFF) == 0) 347344957Smarcel status = status >> 8 & 0xFF; 348344957Smarcel#if JOBS 349344957Smarcel else if ((status & 0xFF) == 0177) 350344957Smarcel status = (status >> 8 & 0x7F) + 128; 351344957Smarcel#endif 352344957Smarcel else 353344957Smarcel status = (status & 0x7F) + 128; 354344957Smarcel if (! iflag) 355344957Smarcel freejob(job); 356344957Smarcel return status; 357344957Smarcel } 358344957Smarcel } else { 359344957Smarcel for (jp = jobtab ; ; jp++) { 360344957Smarcel if (jp >= jobtab + njobs) { /* no running procs */ 361344957Smarcel return 0; 362344957Smarcel } 363344957Smarcel if (jp->used && jp->state == 0) 364344957Smarcel break; 365344957Smarcel } 366344957Smarcel } 367344957Smarcel dowait(1, (struct job *)NULL); 368344957Smarcel } 369344957Smarcel} 370344957Smarcel 371344957Smarcel 372344957Smarcel 373344957Smarceljobidcmd(argc, argv) char **argv; { 374344957Smarcel struct job *jp; 375344957Smarcel int i; 376344957Smarcel 377344957Smarcel jp = getjob(argv[1]); 378344957Smarcel for (i = 0 ; i < jp->nprocs ; ) { 379344957Smarcel out1fmt("%d", jp->ps[i].pid); 380344957Smarcel out1c(++i < jp->nprocs? ' ' : '\n'); 381344957Smarcel } 382344957Smarcel return 0; 383344957Smarcel} 384344957Smarcel 385344957Smarcel 386344957Smarcel 387344957Smarcel/* 388344957Smarcel * Convert a job name to a job structure. 389344957Smarcel */ 390344957Smarcel 391344957SmarcelSTATIC struct job * 392344957Smarcelgetjob(name) 393344957Smarcel char *name; 394344957Smarcel { 395344957Smarcel int jobno; 396344957Smarcel register struct job *jp; 397344957Smarcel int pid; 398344957Smarcel int i; 399344957Smarcel 400344957Smarcel if (name == NULL) { 401344957Smarcel#if JOBS 402344957Smarcelcurrentjob: 403344957Smarcel if ((jobno = curjob) == 0 || jobtab[jobno - 1].used == 0) 404344957Smarcel error("No current job"); 405344957Smarcel return &jobtab[jobno - 1]; 406344957Smarcel#else 407344957Smarcel error("No current job"); 408344957Smarcel#endif 409344957Smarcel } else if (name[0] == '%') { 410344957Smarcel if (is_digit(name[1])) { 411344957Smarcel jobno = number(name + 1); 412344957Smarcel if (jobno > 0 && jobno <= njobs 413344957Smarcel && jobtab[jobno - 1].used != 0) 414344957Smarcel return &jobtab[jobno - 1]; 415344957Smarcel#if JOBS 416344957Smarcel } else if (name[1] == '%' && name[2] == '\0') { 417344957Smarcel goto currentjob; 418344957Smarcel#endif 419344957Smarcel } else { 420344957Smarcel register struct job *found = NULL; 421344957Smarcel for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 422344957Smarcel if (jp->used && jp->nprocs > 0 423344957Smarcel && prefix(name + 1, jp->ps[0].cmd)) { 424344957Smarcel if (found) 425344957Smarcel error("%s: ambiguous", name); 426344957Smarcel found = jp; 427344957Smarcel } 428344957Smarcel } 429344957Smarcel if (found) 430344957Smarcel return found; 431344957Smarcel } 432344957Smarcel } else if (is_number(name)) { 433344957Smarcel pid = number(name); 434344957Smarcel for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 435344957Smarcel if (jp->used && jp->nprocs > 0 436344957Smarcel && jp->ps[jp->nprocs - 1].pid == pid) 437344957Smarcel return jp; 438344957Smarcel } 439344957Smarcel } 440344957Smarcel error("No such job: %s", name); 441344957Smarcel} 442344957Smarcel 443344957Smarcel 444344957Smarcel 445344957Smarcel/* 446344957Smarcel * Return a new job structure, 447344957Smarcel */ 448344957Smarcel 449344957Smarcelstruct job * 450344957Smarcelmakejob(node, nprocs) 451344957Smarcel union node *node; 452344957Smarcel { 453344957Smarcel int i; 454344957Smarcel struct job *jp; 455344957Smarcel 456344957Smarcel for (i = njobs, jp = jobtab ; ; jp++) { 457344957Smarcel if (--i < 0) { 458344957Smarcel INTOFF; 459344957Smarcel if (njobs == 0) { 460344957Smarcel jobtab = ckmalloc(4 * sizeof jobtab[0]); 461344957Smarcel } else { 462344957Smarcel jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 463344957Smarcel bcopy(jobtab, jp, njobs * sizeof jp[0]); 464344957Smarcel ckfree(jobtab); 465344957Smarcel jobtab = jp; 466344957Smarcel } 467344957Smarcel jp = jobtab + njobs; 468344957Smarcel for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 469344957Smarcel INTON; 470344957Smarcel break; 471344957Smarcel } 472344957Smarcel if (jp->used == 0) 473344957Smarcel break; 474344957Smarcel } 475344957Smarcel INTOFF; 476344957Smarcel jp->state = 0; 477344957Smarcel jp->used = 1; 478344957Smarcel jp->changed = 0; 479344957Smarcel jp->nprocs = 0; 480344957Smarcel#if JOBS 481344957Smarcel jp->jobctl = jobctl; 482344957Smarcel#endif 483344957Smarcel if (nprocs > 1) { 484344957Smarcel jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 485344957Smarcel } else { 486344957Smarcel jp->ps = &jp->ps0; 487344957Smarcel } 488344957Smarcel INTON; 489344957Smarcel TRACE(("makejob(0x%x, %d) returns %%%d\n", (int)node, nprocs, jp - jobtab + 1)); 490344957Smarcel return jp; 491344957Smarcel} 492344957Smarcel 493344957Smarcel 494344957Smarcel/* 495344957Smarcel * Fork of a subshell. If we are doing job control, give the subshell its 496344957Smarcel * own process group. Jp is a job structure that the job is to be added to. 497344957Smarcel * N is the command that will be evaluated by the child. Both jp and n may 498344957Smarcel * be NULL. The mode parameter can be one of the following: 499344957Smarcel * FORK_FG - Fork off a foreground process. 500344957Smarcel * FORK_BG - Fork off a background process. 501344957Smarcel * FORK_NOJOB - Like FORK_FG, but don't give the process its own 502344957Smarcel * process group even if job control is on. 503344957Smarcel * 504344957Smarcel * When job control is turned off, background processes have their standard 505344957Smarcel * input redirected to /dev/null (except for the second and later processes 506344957Smarcel * in a pipeline). 507344957Smarcel */ 508344957Smarcel 509344957Smarcelint 510344957Smarcelforkshell(jp, n, mode) 511344957Smarcel union node *n; 512344957Smarcel struct job *jp; 513344957Smarcel { 514344957Smarcel int pid; 515344957Smarcel int pgrp; 516344957Smarcel 517344957Smarcel TRACE(("forkshell(%%%d, 0x%x, %d) called\n", jp - jobtab, (int)n, mode)); 518344957Smarcel INTOFF; 519344957Smarcel pid = fork(); 520344957Smarcel if (pid == -1) { 521344957Smarcel TRACE(("Fork failed, errno=%d\n", errno)); 522344957Smarcel INTON; 523344957Smarcel error("Cannot fork"); 524344957Smarcel } 525344957Smarcel if (pid == 0) { 526344957Smarcel struct job *p; 527344957Smarcel int wasroot; 528344957Smarcel int i; 529344957Smarcel 530344957Smarcel TRACE(("Child shell %d\n", getpid())); 531344957Smarcel wasroot = rootshell; 532344957Smarcel rootshell = 0; 533344957Smarcel for (i = njobs, p = jobtab ; --i >= 0 ; p++) 534344957Smarcel if (p->used) 535344957Smarcel freejob(p); 536344957Smarcel closescript(); 537344957Smarcel INTON; 538344957Smarcel clear_traps(); 539344957Smarcel#if JOBS 540344957Smarcel jobctl = 0; /* do job control only in root shell */ 541344957Smarcel if (wasroot && mode != FORK_NOJOB && mflag) { 542344957Smarcel if (jp == NULL || jp->nprocs == 0) 543344957Smarcel pgrp = getpid(); 544344957Smarcel else 545344957Smarcel pgrp = jp->ps[0].pid; 546344957Smarcel setpgrp(0, pgrp); 547344957Smarcel if (mode == FORK_FG) { 548344957Smarcel /*** this causes superfluous TIOCSPGRPS ***/ 549344957Smarcel if (ioctl(2, TIOCSPGRP, (char *)&pgrp) < 0) 550344957Smarcel error("TIOCSPGRP failed, errno=%d\n", errno); 551344957Smarcel } 552344957Smarcel setsignal(SIGTSTP); 553344957Smarcel setsignal(SIGTTOU); 554344957Smarcel } else if (mode == FORK_BG) { 555344957Smarcel ignoresig(SIGINT); 556344957Smarcel ignoresig(SIGQUIT); 557344957Smarcel if ((jp == NULL || jp->nprocs == 0) && 558344957Smarcel ! fd0_redirected_p ()) { 559344957Smarcel close(0); 560344957Smarcel if (open("/dev/null", O_RDONLY) != 0) 561344957Smarcel error("Can't open /dev/null"); 562344957Smarcel } 563344957Smarcel } 564344957Smarcel#else 565344957Smarcel if (mode == FORK_BG) { 566344957Smarcel ignoresig(SIGINT); 567344957Smarcel ignoresig(SIGQUIT); 568344957Smarcel if ((jp == NULL || jp->nprocs == 0) && 569344957Smarcel ! fd0_redirected_p ()) { 570344957Smarcel close(0); 571344957Smarcel if (open("/dev/null", O_RDONLY) != 0) 572344957Smarcel error("Can't open /dev/null"); 573344957Smarcel } 574344957Smarcel } 575344957Smarcel#endif 576344957Smarcel if (wasroot && iflag) { 577 setsignal(SIGINT); 578 setsignal(SIGQUIT); 579 setsignal(SIGTERM); 580 } 581 return pid; 582 } 583 if (rootshell && mode != FORK_NOJOB && mflag) { 584 if (jp == NULL || jp->nprocs == 0) 585 pgrp = pid; 586 else 587 pgrp = jp->ps[0].pid; 588 setpgrp(pid, pgrp); 589 } 590 if (mode == FORK_BG) 591 backgndpid = pid; /* set $! */ 592 if (jp) { 593 struct procstat *ps = &jp->ps[jp->nprocs++]; 594 ps->pid = pid; 595 ps->status = -1; 596 ps->cmd = nullstr; 597 if (iflag && rootshell && n) 598 ps->cmd = commandtext(n); 599 } 600 INTON; 601 TRACE(("In parent shell: child = %d\n", pid)); 602 return pid; 603} 604 605 606 607/* 608 * Wait for job to finish. 609 * 610 * Under job control we have the problem that while a child process is 611 * running interrupts generated by the user are sent to the child but not 612 * to the shell. This means that an infinite loop started by an inter- 613 * active user may be hard to kill. With job control turned off, an 614 * interactive user may place an interactive program inside a loop. If 615 * the interactive program catches interrupts, the user doesn't want 616 * these interrupts to also abort the loop. The approach we take here 617 * is to have the shell ignore interrupt signals while waiting for a 618 * forground process to terminate, and then send itself an interrupt 619 * signal if the child process was terminated by an interrupt signal. 620 * Unfortunately, some programs want to do a bit of cleanup and then 621 * exit on interrupt; unless these processes terminate themselves by 622 * sending a signal to themselves (instead of calling exit) they will 623 * confuse this approach. 624 */ 625 626int 627waitforjob(jp) 628 register struct job *jp; 629 { 630#if JOBS 631 int mypgrp = getpgrp(0); 632#endif 633 int status; 634 int st; 635 636 INTOFF; 637 TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1)); 638 while (jp->state == 0) { 639 dowait(1, jp); 640 } 641#if JOBS 642 if (jp->jobctl) { 643 if (ioctl(2, TIOCSPGRP, (char *)&mypgrp) < 0) 644 error("TIOCSPGRP failed, errno=%d\n", errno); 645 } 646 if (jp->state == JOBSTOPPED) 647 curjob = jp - jobtab + 1; 648#endif 649 status = jp->ps[jp->nprocs - 1].status; 650 /* convert to 8 bits */ 651 if ((status & 0xFF) == 0) 652 st = status >> 8 & 0xFF; 653#if JOBS 654 else if ((status & 0xFF) == 0177) 655 st = (status >> 8 & 0x7F) + 128; 656#endif 657 else 658 st = (status & 0x7F) + 128; 659 if (! JOBS || jp->state == JOBDONE) 660 freejob(jp); 661 CLEAR_PENDING_INT; 662 if ((status & 0x7F) == SIGINT) 663 kill(getpid(), SIGINT); 664 INTON; 665 return st; 666} 667 668 669 670/* 671 * Wait for a process to terminate. 672 */ 673 674STATIC int 675dowait(block, job) 676 struct job *job; 677 { 678 int pid; 679 int status; 680 struct procstat *sp; 681 struct job *jp; 682 struct job *thisjob; 683 int done; 684 int stopped; 685 int core; 686 687 TRACE(("dowait(%d) called\n", block)); 688 do { 689 pid = waitproc(block, &status); 690 TRACE(("wait returns %d, status=%d\n", pid, status)); 691 } while (pid == -1 && errno == EINTR); 692 if (pid <= 0) 693 return pid; 694 INTOFF; 695 thisjob = NULL; 696 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 697 if (jp->used) { 698 done = 1; 699 stopped = 1; 700 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 701 if (sp->pid == -1) 702 continue; 703 if (sp->pid == pid) { 704 TRACE(("Changin status of proc %d from 0x%x to 0x%x\n", pid, sp->status, status)); 705 sp->status = status; 706 thisjob = jp; 707 } 708 if (sp->status == -1) 709 stopped = 0; 710 else if ((sp->status & 0377) == 0177) 711 done = 0; 712 } 713 if (stopped) { /* stopped or done */ 714 int state = done? JOBDONE : JOBSTOPPED; 715 if (jp->state != state) { 716 TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 717 jp->state = state; 718#if JOBS 719 if (done && curjob == jp - jobtab + 1) 720 curjob = 0; /* no current job */ 721#endif 722 } 723 } 724 } 725 } 726 INTON; 727 if (! rootshell || ! iflag || (job && thisjob == job)) { 728#if JOBS 729 if ((status & 0xFF) == 0177) 730 status >>= 8; 731#endif 732 core = status & 0x80; 733 status &= 0x7F; 734 if (status != 0 && status != SIGINT && status != SIGPIPE) { 735 if (thisjob != job) 736 outfmt(out2, "%d: ", pid); 737#if JOBS 738 if (status == SIGTSTP && rootshell && iflag) 739 outfmt(out2, "%%%d ", job - jobtab + 1); 740#endif 741 if (status <= MAXSIG && sigmesg[status]) 742 out2str(sigmesg[status]); 743 else 744 outfmt(out2, "Signal %d", status); 745 if (core) 746 out2str(" - core dumped"); 747 out2c('\n'); 748 flushout(&errout); 749 } else { 750 TRACE(("Not printing status: status=%d\n", status)); 751 } 752 } else { 753 TRACE(("Not printing status, rootshell=%d, job=0x%x\n", rootshell, job)); 754 if (thisjob) 755 thisjob->changed = 1; 756 } 757 return pid; 758} 759 760 761 762/* 763 * Do a wait system call. If job control is compiled in, we accept 764 * stopped processes. If block is zero, we return a value of zero 765 * rather than blocking. 766 * 767 * System V doesn't have a non-blocking wait system call. It does 768 * have a SIGCLD signal that is sent to a process when one of it's 769 * children dies. The obvious way to use SIGCLD would be to install 770 * a handler for SIGCLD which simply bumped a counter when a SIGCLD 771 * was received, and have waitproc bump another counter when it got 772 * the status of a process. Waitproc would then know that a wait 773 * system call would not block if the two counters were different. 774 * This approach doesn't work because if a process has children that 775 * have not been waited for, System V will send it a SIGCLD when it 776 * installs a signal handler for SIGCLD. What this means is that when 777 * a child exits, the shell will be sent SIGCLD signals continuously 778 * until is runs out of stack space, unless it does a wait call before 779 * restoring the signal handler. The code below takes advantage of 780 * this (mis)feature by installing a signal handler for SIGCLD and 781 * then checking to see whether it was called. If there are any 782 * children to be waited for, it will be. 783 * 784 * If neither SYSV nor BSD is defined, we don't implement nonblocking 785 * waits at all. In this case, the user will not be informed when 786 * a background process until the next time she runs a real program 787 * (as opposed to running a builtin command or just typing return), 788 * and the jobs command may give out of date information. 789 */ 790 791#ifdef SYSV 792STATIC int gotsigchild; 793 794STATIC int onsigchild() { 795 gotsigchild = 1; 796} 797#endif 798 799 800STATIC int 801waitproc(block, status) 802 int *status; 803 { 804#ifdef BSD 805 int flags; 806 807#if JOBS 808 flags = WUNTRACED; 809#else 810 flags = 0; 811#endif 812 if (block == 0) 813 flags |= WNOHANG; 814 return wait3(status, flags, (struct rusage *)NULL); 815#else 816#ifdef SYSV 817 int (*save)(); 818 819 if (block == 0) { 820 gotsigchild = 0; 821 save = signal(SIGCLD, onsigchild); 822 signal(SIGCLD, save); 823 if (gotsigchild == 0) 824 return 0; 825 } 826 return wait(status); 827#else 828 if (block == 0) 829 return 0; 830 return wait(status); 831#endif 832#endif 833} 834 835/* 836 * return 1 if there are stopped jobs, otherwise 0 837 */ 838int job_warning = 0; 839int 840stoppedjobs() 841{ 842 register int jobno; 843 register struct job *jp; 844 845 if (job_warning) 846 return (0); 847 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 848 if (jp->used == 0) 849 continue; 850 if (jp->state == JOBSTOPPED) { 851 out2str("You have stopped jobs.\n"); 852 job_warning = 2; 853 return (1); 854 } 855 } 856 857 return (0); 858} 859 860/* 861 * Return a string identifying a command (to be printed by the 862 * jobs command. 863 */ 864 865STATIC char *cmdnextc; 866STATIC int cmdnleft; 867STATIC void cmdtxt(), cmdputs(); 868#define MAXCMDTEXT 200 869 870char * 871commandtext(n) 872 union node *n; 873 { 874 char *name; 875 876 cmdnextc = name = ckmalloc(MAXCMDTEXT); 877 cmdnleft = MAXCMDTEXT - 4; 878 cmdtxt(n); 879 *cmdnextc = '\0'; 880 return name; 881} 882 883 884STATIC void 885cmdtxt(n) 886 union node *n; 887 { 888 union node *np; 889 struct nodelist *lp; 890 char *p; 891 int i; 892 char s[2]; 893 894 if (n == NULL) 895 return; 896 switch (n->type) { 897 case NSEMI: 898 cmdtxt(n->nbinary.ch1); 899 cmdputs("; "); 900 cmdtxt(n->nbinary.ch2); 901 break; 902 case NAND: 903 cmdtxt(n->nbinary.ch1); 904 cmdputs(" && "); 905 cmdtxt(n->nbinary.ch2); 906 break; 907 case NOR: 908 cmdtxt(n->nbinary.ch1); 909 cmdputs(" || "); 910 cmdtxt(n->nbinary.ch2); 911 break; 912 case NPIPE: 913 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 914 cmdtxt(lp->n); 915 if (lp->next) 916 cmdputs(" | "); 917 } 918 break; 919 case NSUBSHELL: 920 cmdputs("("); 921 cmdtxt(n->nredir.n); 922 cmdputs(")"); 923 break; 924 case NREDIR: 925 case NBACKGND: 926 cmdtxt(n->nredir.n); 927 break; 928 case NIF: 929 cmdputs("if "); 930 cmdtxt(n->nif.test); 931 cmdputs("; then "); 932 cmdtxt(n->nif.ifpart); 933 cmdputs("..."); 934 break; 935 case NWHILE: 936 cmdputs("while "); 937 goto until; 938 case NUNTIL: 939 cmdputs("until "); 940until: 941 cmdtxt(n->nbinary.ch1); 942 cmdputs("; do "); 943 cmdtxt(n->nbinary.ch2); 944 cmdputs("; done"); 945 break; 946 case NFOR: 947 cmdputs("for "); 948 cmdputs(n->nfor.var); 949 cmdputs(" in ..."); 950 break; 951 case NCASE: 952 cmdputs("case "); 953 cmdputs(n->ncase.expr->narg.text); 954 cmdputs(" in ..."); 955 break; 956 case NDEFUN: 957 cmdputs(n->narg.text); 958 cmdputs("() ..."); 959 break; 960 case NCMD: 961 for (np = n->ncmd.args ; np ; np = np->narg.next) { 962 cmdtxt(np); 963 if (np->narg.next) 964 cmdputs(" "); 965 } 966 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 967 cmdputs(" "); 968 cmdtxt(np); 969 } 970 break; 971 case NARG: 972 cmdputs(n->narg.text); 973 break; 974 case NTO: 975 p = ">"; i = 1; goto redir; 976 case NAPPEND: 977 p = ">>"; i = 1; goto redir; 978 case NTOFD: 979 p = ">&"; i = 1; goto redir; 980 case NFROM: 981 p = "<"; i = 0; goto redir; 982 case NFROMFD: 983 p = "<&"; i = 0; goto redir; 984redir: 985 if (n->nfile.fd != i) { 986 s[0] = n->nfile.fd + '0'; 987 s[1] = '\0'; 988 cmdputs(s); 989 } 990 cmdputs(p); 991 if (n->type == NTOFD || n->type == NFROMFD) { 992 s[0] = n->ndup.dupfd + '0'; 993 s[1] = '\0'; 994 cmdputs(s); 995 } else { 996 cmdtxt(n->nfile.fname); 997 } 998 break; 999 case NHERE: 1000 case NXHERE: 1001 cmdputs("<<..."); 1002 break; 1003 default: 1004 cmdputs("???"); 1005 break; 1006 } 1007} 1008 1009 1010 1011STATIC void 1012cmdputs(s) 1013 char *s; 1014 { 1015 register char *p, *q; 1016 register char c; 1017 int subtype = 0; 1018 1019 if (cmdnleft <= 0) 1020 return; 1021 p = s; 1022 q = cmdnextc; 1023 while ((c = *p++) != '\0') { 1024 if (c == CTLESC) 1025 *q++ = *p++; 1026 else if (c == CTLVAR) { 1027 *q++ = '$'; 1028 if (--cmdnleft > 0) 1029 *q++ = '{'; 1030 subtype = *p++; 1031 } else if (c == '=' && subtype != 0) { 1032 *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL]; 1033 subtype = 0; 1034 } else if (c == CTLENDVAR) { 1035 *q++ = '}'; 1036 } else if (c == CTLBACKQ | c == CTLBACKQ+CTLQUOTE) 1037 cmdnleft++; /* ignore it */ 1038 else 1039 *q++ = c; 1040 if (--cmdnleft <= 0) { 1041 *q++ = '.'; 1042 *q++ = '.'; 1043 *q++ = '.'; 1044 break; 1045 } 1046 } 1047 cmdnextc = q; 1048} 1049