sh.sem.c revision 69408
1/* $Header: /src/pub/tcsh/sh.sem.c,v 3.51 2000/11/11 23:03:38 christos Exp $ */ 2/* 3 * sh.sem.c: I/O redirections and job forking. A touchy issue! 4 * Most stuff with builtins is incorrect 5 */ 6/*- 7 * Copyright (c) 1980, 1991 The Regents of the University of California. 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38#include "sh.h" 39 40RCSID("$Id: sh.sem.c,v 3.51 2000/11/11 23:03:38 christos Exp $") 41 42#include "tc.h" 43#include "tw.h" 44#ifdef WINNT_NATIVE 45#include "nt.const.h" 46#endif /*WINNT_NATIVE*/ 47 48#ifdef CLOSE_ON_EXEC 49# ifndef SUNOS4 50# ifndef CLEX_DUPS 51# define CLEX_DUPS 52# endif /* CLEX_DUPS */ 53# endif /* !SUNOS4 */ 54#endif /* CLOSE_ON_EXEC */ 55 56#if defined(__sparc__) || defined(sparc) 57# if !defined(MACH) && SYSVREL == 0 && !defined(Lynx) && !defined(BSD4_4) && !defined(linux) 58# include <vfork.h> 59# endif /* !MACH && SYSVREL == 0 && !Lynx && !BSD4_4 && !linux */ 60#endif /* __sparc__ || sparc */ 61 62#ifdef VFORK 63static sigret_t vffree __P((int)); 64#endif 65static Char *splicepipe __P((struct command *, Char *)); 66static void doio __P((struct command *, int *, int *)); 67static void chkclob __P((char *)); 68 69/* 70 * C shell 71 */ 72 73/* 74 * For SVR4, there are problems with pipelines having the first process as 75 * the group leader. The problem occurs when the first process exits before 76 * the others have a chance to setpgid(). This is because in SVR4 you can't 77 * have a zombie as a group leader. The solution I have used is to reverse 78 * the order in which pipelines are started, making the last process the 79 * group leader. (Note I am not using 'pipeline' in the generic sense -- I 80 * mean processes connected by '|'.) I don't know yet if this causes other 81 * problems. 82 * 83 * All the changes for this are in execute(), and are enclosed in 84 * '#ifdef BACKPIPE' 85 * 86 * David Dawes (dawes@physics.su.oz.au) Oct 1991 87 */ 88 89/*VARARGS 1*/ 90void 91execute(t, wanttty, pipein, pipeout) 92 register struct command *t; 93 int wanttty; 94 int *pipein, *pipeout; 95{ 96#ifdef VFORK 97 extern bool use_fork; /* use fork() instead of vfork()? */ 98#endif 99 100 bool forked = 0; 101 struct biltins *bifunc; 102 int pid = 0; 103 int pv[2]; 104#ifdef BSDSIGS 105 static sigmask_t csigmask; 106#endif /* BSDSIGS */ 107#ifdef VFORK 108 static int onosigchld = 0; 109#endif /* VFORK */ 110 static int nosigchld = 0; 111 112 (void) &wanttty; 113 (void) &forked; 114 (void) &bifunc; 115 116 if (t == 0) 117 return; 118 119#ifdef WINNT_NATIVE 120 { 121 if ((varval(STRNTslowexec) == STRNULL) && 122 !t->t_dcdr && !t->t_dcar && !t->t_dflg && !didfds && 123 (intty || intact) && (t->t_dtyp == NODE_COMMAND) && 124 !isbfunc(t)) { 125 if ((t->t_dcom[0][0] & (QUOTE | TRIM)) == QUOTE) 126 (void) Strcpy(t->t_dcom[0], t->t_dcom[0] + 1); 127 Dfix(t); 128 if (nt_try_fast_exec(t) == 0) 129 return; 130 } 131 } 132#endif /* WINNT_NATIVE */ 133 134 /* 135 * Ed hutchins@sgi.com & Dominic dbg@sgi.com 136 * Sat Feb 25 03:13:11 PST 1995 137 * try implicit cd if we have a 1 word command 138 */ 139 if (implicit_cd && (intty || intact) && t->t_dcom && t->t_dcom[0] && 140 t->t_dcom[0][0] && (blklen(t->t_dcom) == 1) && !noexec) { 141 Char sCName[MAXPATHLEN]; 142 Char *pCN; 143 struct stat stbuf; 144 char *pathname; 145 146 dollar(sCName, t->t_dcom[0]); 147 pCN = sCName; 148 if (pCN[0] == '~') { 149 Char sCPath[MAXPATHLEN]; 150 Char *pCP = sCPath; 151 152 ++pCN; 153 while (*pCN && *pCN != '/') 154 *pCP++ = *pCN++; 155 *pCP = 0; 156 if (sCPath[0]) 157 gethdir(sCPath); 158 else 159 (void) Strcpy(sCPath, varval(STRhome)); 160 catn(sCPath, pCN, MAXPATHLEN); 161 (void) Strcpy(sCName, sCPath); 162 } 163 164 pathname = short2str(sCName); 165 /* if this is a dir, tack a "cd" on as the first arg */ 166 if ((stat(pathname, &stbuf) != -1 && S_ISDIR(stbuf.st_mode)) 167#ifdef WINNT_NATIVE 168 || (pathname[0] && pathname[1] == ':' && pathname[2] == '\0') 169#endif /* WINNT_NATIVE */ 170 ) { 171 Char *vCD[2]; 172 Char **ot_dcom = t->t_dcom; 173 174 vCD[0] = Strsave(STRcd); 175 vCD[1] = NULL; 176 t->t_dcom = blkspl(vCD, ot_dcom); 177 if (implicit_cd > 1) { 178 blkpr(t->t_dcom); 179 xputchar( '\n' ); 180 } 181 xfree((ptr_t) ot_dcom); 182 } 183 } 184 185 /* 186 * From: Michael Schroeder <mlschroe@immd4.informatik.uni-erlangen.de> 187 * Don't check for wantty > 0... 188 */ 189 if (t->t_dflg & F_AMPERSAND) 190 wanttty = 0; 191 switch (t->t_dtyp) { 192 193 case NODE_COMMAND: 194 if ((t->t_dcom[0][0] & (QUOTE | TRIM)) == QUOTE) 195 (void) Strcpy(t->t_dcom[0], t->t_dcom[0] + 1); 196 if ((t->t_dflg & F_REPEAT) == 0) 197 Dfix(t); /* $ " ' \ */ 198 if (t->t_dcom[0] == 0) { 199 return; 200 } 201 /*FALLTHROUGH*/ 202 203 case NODE_PAREN: 204#ifdef BACKPIPE 205 if (t->t_dflg & F_PIPEIN) 206 mypipe(pipein); 207#else /* !BACKPIPE */ 208 if (t->t_dflg & F_PIPEOUT) 209 mypipe(pipeout); 210#endif /* BACKPIPE */ 211 /* 212 * Must do << early so parent will know where input pointer should be. 213 * If noexec then this is all we do. 214 */ 215 if (t->t_dflg & F_READ) { 216 (void) close(0); 217 heredoc(t->t_dlef); 218 if (noexec) 219 (void) close(0); 220 } 221 222 set(STRstatus, Strsave(STR0), VAR_READWRITE); 223 224 /* 225 * This mess is the necessary kludge to handle the prefix builtins: 226 * nice, nohup, time. These commands can also be used by themselves, 227 * and this is not handled here. This will also work when loops are 228 * parsed. 229 */ 230 while (t->t_dtyp == NODE_COMMAND) 231 if (eq(t->t_dcom[0], STRnice)) { 232 if (t->t_dcom[1]) { 233 if (strchr("+-", t->t_dcom[1][0])) { 234 if (t->t_dcom[2]) { 235 setname("nice"); 236 t->t_nice = 237 getn(t->t_dcom[1]); 238 lshift(t->t_dcom, 2); 239 t->t_dflg |= F_NICE; 240 } 241 else 242 break; 243 } 244 else { 245 t->t_nice = 4; 246 lshift(t->t_dcom, 1); 247 t->t_dflg |= F_NICE; 248 } 249 } 250 else 251 break; 252 } 253 else if (eq(t->t_dcom[0], STRnohup)) { 254 if (t->t_dcom[1]) { 255 t->t_dflg |= F_NOHUP; 256 lshift(t->t_dcom, 1); 257 } 258 else 259 break; 260 } 261 else if (eq(t->t_dcom[0], STRhup)) { 262 if (t->t_dcom[1]) { 263 t->t_dflg |= F_HUP; 264 lshift(t->t_dcom, 1); 265 } 266 else 267 break; 268 } 269 else if (eq(t->t_dcom[0], STRtime)) { 270 if (t->t_dcom[1]) { 271 t->t_dflg |= F_TIME; 272 lshift(t->t_dcom, 1); 273 } 274 else 275 break; 276 } 277#ifdef F_VER 278 else if (eq(t->t_dcom[0], STRver)) 279 if (t->t_dcom[1] && t->t_dcom[2]) { 280 setname("ver"); 281 t->t_systype = getv(t->t_dcom[1]); 282 lshift(t->t_dcom, 2); 283 t->t_dflg |= F_VER; 284 } 285 else 286 break; 287#endif /* F_VER */ 288 else 289 break; 290 291 /* is it a command */ 292 if (t->t_dtyp == NODE_COMMAND) { 293 /* 294 * Check if we have a builtin function and remember which one. 295 */ 296 bifunc = isbfunc(t); 297 if (noexec && bifunc) { 298 /* 299 * Continue for builtins that are part of the scripting language 300 */ 301 if (bifunc->bfunct != (bfunc_t)dobreak && 302 bifunc->bfunct != (bfunc_t)docontin && 303 bifunc->bfunct != (bfunc_t)doelse && 304 bifunc->bfunct != (bfunc_t)doend && 305 bifunc->bfunct != (bfunc_t)doforeach&& 306 bifunc->bfunct != (bfunc_t)dogoto && 307 bifunc->bfunct != (bfunc_t)doif && 308 bifunc->bfunct != (bfunc_t)dorepeat && 309 bifunc->bfunct != (bfunc_t)doswbrk && 310 bifunc->bfunct != (bfunc_t)doswitch && 311 bifunc->bfunct != (bfunc_t)dowhile && 312 bifunc->bfunct != (bfunc_t)dozip) 313 break; 314 } 315 } 316 else { /* not a command */ 317 bifunc = NULL; 318 if (noexec) 319 break; 320 } 321 322 /* 323 * We fork only if we are timed, or are not the end of a parenthesized 324 * list and not a simple builtin function. Simple meaning one that is 325 * not pipedout, niced, nohupped, or &'d. It would be nice(?) to not 326 * fork in some of these cases. 327 */ 328 /* 329 * Prevent forking cd, pushd, popd, chdir cause this will cause the 330 * shell not to change dir! 331 */ 332#ifdef BACKPIPE 333 /* 334 * Can't have NOFORK for the tail of a pipe - because it is not the 335 * last command spawned (even if it is at the end of a parenthesised 336 * list). 337 */ 338 if (t->t_dflg & F_PIPEIN) 339 t->t_dflg &= ~(F_NOFORK); 340#endif /* BACKPIPE */ 341 if (bifunc && (bifunc->bfunct == (bfunc_t)dochngd || 342 bifunc->bfunct == (bfunc_t)dopushd || 343 bifunc->bfunct == (bfunc_t)dopopd)) 344 t->t_dflg &= ~(F_NICE); 345 if (((t->t_dflg & F_TIME) || ((t->t_dflg & F_NOFORK) == 0 && 346 (!bifunc || t->t_dflg & 347 (F_PIPEOUT | F_AMPERSAND | F_NICE | F_NOHUP | F_HUP)))) || 348 /* 349 * We have to fork for eval too. 350 */ 351 (bifunc && (t->t_dflg & F_PIPEIN) != 0 && 352 bifunc->bfunct == (bfunc_t)doeval)) { 353#ifdef VFORK 354 if (t->t_dtyp == NODE_PAREN || 355 t->t_dflg & (F_REPEAT | F_AMPERSAND) || bifunc) 356#endif /* VFORK */ 357 { 358 forked++; 359 /* 360 * We need to block SIGCHLD here, so that if the process does 361 * not die before we can set the process group 362 */ 363 if (wanttty >= 0 && !nosigchld) { 364#ifdef BSDSIGS 365 csigmask = sigblock(sigmask(SIGCHLD)); 366#else /* !BSDSIGS */ 367 (void) sighold(SIGCHLD); 368#endif /* BSDSIGS */ 369 370 nosigchld = 1; 371 } 372 373 pid = pfork(t, wanttty); 374 if (pid == 0 && nosigchld) { 375#ifdef BSDSIGS 376 (void) sigsetmask(csigmask); 377#else /* !BSDSIGS */ 378 (void) sigrelse(SIGCHLD); 379#endif /* BSDSIGS */ 380 nosigchld = 0; 381 } 382 else if (pid != 0 && (t->t_dflg & F_AMPERSAND)) 383 backpid = pid; 384 } 385 386#ifdef VFORK 387 else { 388 int ochild, osetintr, ohaderr, odidfds; 389 int oSHIN, oSHOUT, oSHDIAG, oOLDSTD, otpgrp; 390 int oisoutatty, oisdiagatty; 391 392# ifndef CLOSE_ON_EXEC 393 int odidcch; 394# endif /* !CLOSE_ON_EXEC */ 395# ifdef BSDSIGS 396 sigmask_t omask, ocsigmask; 397# endif /* BSDSIGS */ 398 399 /* 400 * Prepare for the vfork by saving everything that the child 401 * corrupts before it exec's. Note that in some signal 402 * implementations which keep the signal info in user space 403 * (e.g. Sun's) it will also be necessary to save and restore 404 * the current sigvec's for the signals the child touches 405 * before it exec's. 406 */ 407 408 /* 409 * Sooooo true... If this is a Sun, save the sigvec's. (Skip 410 * Gilbrech - 11/22/87) 411 */ 412# ifdef SAVESIGVEC 413 sigvec_t savesv[NSIGSAVED]; 414 sigmask_t savesm; 415 416# endif /* SAVESIGVEC */ 417 if (wanttty >= 0 && !nosigchld && !noexec) { 418# ifdef BSDSIGS 419 csigmask = sigblock(sigmask(SIGCHLD)); 420# else /* !BSDSIGS */ 421 (void) sighold(SIGCHLD); 422# endif /* BSDSIGS */ 423 nosigchld = 1; 424 } 425# ifdef BSDSIGS 426 omask = sigblock(sigmask(SIGCHLD)|sigmask(SIGINT)); 427# else /* !BSDSIGS */ 428 (void) sighold(SIGCHLD); 429 (void) sighold(SIGINT); 430# endif /* BSDSIGS */ 431 ochild = child; 432 osetintr = setintr; 433 ohaderr = haderr; 434 odidfds = didfds; 435# ifndef CLOSE_ON_EXEC 436 odidcch = didcch; 437# endif /* !CLOSE_ON_EXEC */ 438 oSHIN = SHIN; 439 oSHOUT = SHOUT; 440 oSHDIAG = SHDIAG; 441 oOLDSTD = OLDSTD; 442 otpgrp = tpgrp; 443 oisoutatty = isoutatty; 444 oisdiagatty = isdiagatty; 445# ifdef BSDSIGS 446 ocsigmask = csigmask; 447# endif /* BSDSIGS */ 448 onosigchld = nosigchld; 449 Vsav = Vdp = 0; 450 Vexpath = 0; 451 Vt = 0; 452# ifdef SAVESIGVEC 453 savesm = savesigvec(savesv); 454# endif /* SAVESIGVEC */ 455 if (use_fork) 456 pid = fork(); 457 else 458 pid = vfork(); 459 460 if (pid < 0) { 461# ifdef BSDSIGS 462# ifdef SAVESIGVEC 463 restoresigvec(savesv, savesm); 464# endif /* SAVESIGVEC */ 465 (void) sigsetmask(omask); 466# else /* !BSDSIGS */ 467 (void) sigrelse(SIGCHLD); 468 (void) sigrelse(SIGINT); 469# endif /* BSDSIGS */ 470 stderror(ERR_NOPROC); 471 } 472 forked++; 473 if (pid) { /* parent */ 474# ifdef SAVESIGVEC 475 restoresigvec(savesv, savesm); 476# endif /* SAVESIGVEC */ 477 child = ochild; 478 setintr = osetintr; 479 haderr = ohaderr; 480 didfds = odidfds; 481 SHIN = oSHIN; 482# ifndef CLOSE_ON_EXEC 483 didcch = odidcch; 484# endif /* !CLOSE_ON_EXEC */ 485 SHOUT = oSHOUT; 486 SHDIAG = oSHDIAG; 487 OLDSTD = oOLDSTD; 488 tpgrp = otpgrp; 489 isoutatty = oisoutatty; 490 isdiagatty = oisdiagatty; 491# ifdef BSDSIGS 492 csigmask = ocsigmask; 493# endif /* BSDSIGS */ 494 nosigchld = onosigchld; 495 496 xfree((ptr_t) Vsav); 497 Vsav = 0; 498 xfree((ptr_t) Vdp); 499 Vdp = 0; 500 xfree((ptr_t) Vexpath); 501 Vexpath = 0; 502 blkfree((Char **) Vt); 503 Vt = 0; 504 /* this is from pfork() */ 505 palloc(pid, t); 506# ifdef BSDSIGS 507 (void) sigsetmask(omask); 508# else /* !BSDSIGS */ 509 (void) sigrelse(SIGCHLD); 510 (void) sigrelse(SIGINT); 511# endif /* BSDSIGS */ 512 } 513 else { /* child */ 514 /* this is from pfork() */ 515 int pgrp; 516 bool ignint = 0; 517 if (nosigchld) { 518# ifdef BSDSIGS 519 (void) sigsetmask(csigmask); 520# else /* !BSDSIGS */ 521 (void) sigrelse(SIGCHLD); 522# endif /* BSDSIGS */ 523 nosigchld = 0; 524 } 525 526 if (setintr) 527 ignint = (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT)) 528 || (gointr && eq(gointr, STRminus)); 529 pgrp = pcurrjob ? pcurrjob->p_jobid : getpid(); 530 child++; 531 if (setintr) { 532 setintr = 0; 533/* 534 * casts made right for SunOS 4.0 by Douglas C. Schmidt 535 * <schmidt%sunshine.ics.uci.edu@ROME.ICS.UCI.EDU> 536 * (thanks! -- PWP) 537 * 538 * ignint ifs cleaned by Johan Widen <mcvax!osiris.sics.se!jw@uunet.UU.NET> 539 * (thanks again) 540 */ 541 if (ignint) { 542 (void) signal(SIGINT, SIG_IGN); 543 (void) signal(SIGQUIT, SIG_IGN); 544 } 545 else { 546 (void) signal(SIGINT, vffree); 547 (void) signal(SIGQUIT, SIG_DFL); 548 } 549# ifdef BSDJOBS 550 if (wanttty >= 0) { 551 (void) signal(SIGTSTP, SIG_DFL); 552 (void) signal(SIGTTIN, SIG_DFL); 553 (void) signal(SIGTTOU, SIG_DFL); 554 } 555# endif /* BSDJOBS */ 556 557 (void) signal(SIGTERM, parterm); 558 } 559 else if (tpgrp == -1 && 560 (t->t_dflg & F_NOINTERRUPT)) { 561 (void) signal(SIGINT, SIG_IGN); 562 (void) signal(SIGQUIT, SIG_IGN); 563 } 564 565 pgetty(wanttty, pgrp); 566 567 if (t->t_dflg & F_NOHUP) 568 (void) signal(SIGHUP, SIG_IGN); 569 if (t->t_dflg & F_HUP) 570 (void) signal(SIGHUP, SIG_DFL); 571 if (t->t_dflg & F_NICE) { 572 int nval = SIGN_EXTEND_CHAR(t->t_nice); 573# ifdef BSDNICE 574 (void) setpriority(PRIO_PROCESS, 0, nval); 575# else /* !BSDNICE */ 576 (void) nice(nval); 577# endif /* BSDNICE */ 578 } 579# ifdef F_VER 580 if (t->t_dflg & F_VER) { 581 tsetenv(STRSYSTYPE, t->t_systype ? STRbsd43 : STRsys53); 582 dohash(NULL, NULL); 583 } 584# endif /* F_VER */ 585 } 586 587 } 588#endif /* VFORK */ 589 } 590 if (pid != 0) { 591 /* 592 * It would be better if we could wait for the whole job when we 593 * knew the last process had been started. Pwait, in fact, does 594 * wait for the whole job anyway, but this test doesn't really 595 * express our intentions. 596 */ 597#ifdef BACKPIPE 598 if (didfds == 0 && t->t_dflg & F_PIPEOUT) { 599 (void) close(pipeout[0]); 600 (void) close(pipeout[1]); 601 } 602 if ((t->t_dflg & F_PIPEIN) != 0) 603 break; 604#else /* !BACKPIPE */ 605 if (didfds == 0 && t->t_dflg & F_PIPEIN) { 606 (void) close(pipein[0]); 607 (void) close(pipein[1]); 608 } 609 if ((t->t_dflg & F_PIPEOUT) != 0) 610 break; 611#endif /* BACKPIPE */ 612 613 if (nosigchld) { 614#ifdef BSDSIGS 615 (void) sigsetmask(csigmask); 616#else /* !BSDSIGS */ 617 (void) sigrelse(SIGCHLD); 618#endif /* BSDSIGS */ 619 nosigchld = 0; 620 } 621 if ((t->t_dflg & F_AMPERSAND) == 0) 622 pwait(); 623 break; 624 } 625 626 doio(t, pipein, pipeout); 627#ifdef BACKPIPE 628 if (t->t_dflg & F_PIPEIN) { 629 (void) close(pipein[0]); 630 (void) close(pipein[1]); 631 } 632#else /* !BACKPIPE */ 633 if (t->t_dflg & F_PIPEOUT) { 634 (void) close(pipeout[0]); 635 (void) close(pipeout[1]); 636 } 637#endif /* BACKPIPE */ 638 /* 639 * Perform a builtin function. If we are not forked, arrange for 640 * possible stopping 641 */ 642 if (bifunc) { 643 func(t, bifunc); 644 if (forked) 645 exitstat(); 646 break; 647 } 648 if (t->t_dtyp != NODE_PAREN) { 649 doexec(t); 650 /* NOTREACHED */ 651 } 652 /* 653 * For () commands must put new 0,1,2 in FSH* and recurse 654 */ 655 OLDSTD = dcopy(0, FOLDSTD); 656 SHOUT = dcopy(1, FSHOUT); 657 isoutatty = isatty(SHOUT); 658 SHDIAG = dcopy(2, FSHDIAG); 659 isdiagatty = isatty(SHDIAG); 660 (void) close(SHIN); 661 SHIN = -1; 662#ifndef CLOSE_ON_EXEC 663 didcch = 0; 664#endif /* !CLOSE_ON_EXEC */ 665 didfds = 0; 666 wanttty = -1; 667 t->t_dspr->t_dflg |= t->t_dflg & F_NOINTERRUPT; 668 execute(t->t_dspr, wanttty, NULL, NULL); 669 exitstat(); 670 671 case NODE_PIPE: 672#ifdef BACKPIPE 673 t->t_dcdr->t_dflg |= F_PIPEIN | (t->t_dflg & 674 (F_PIPEOUT | F_AMPERSAND | F_NOFORK | F_NOINTERRUPT)); 675 execute(t->t_dcdr, wanttty, pv, pipeout); 676 t->t_dcar->t_dflg |= F_PIPEOUT | 677 (t->t_dflg & (F_PIPEIN | F_AMPERSAND | F_STDERR | F_NOINTERRUPT)); 678 execute(t->t_dcar, wanttty, pipein, pv); 679#else /* !BACKPIPE */ 680 t->t_dcar->t_dflg |= F_PIPEOUT | 681 (t->t_dflg & (F_PIPEIN | F_AMPERSAND | F_STDERR | F_NOINTERRUPT)); 682 execute(t->t_dcar, wanttty, pipein, pv); 683 t->t_dcdr->t_dflg |= F_PIPEIN | (t->t_dflg & 684 (F_PIPEOUT | F_AMPERSAND | F_NOFORK | F_NOINTERRUPT)); 685 execute(t->t_dcdr, wanttty, pv, pipeout); 686#endif /* BACKPIPE */ 687 break; 688 689 case NODE_LIST: 690 if (t->t_dcar) { 691 t->t_dcar->t_dflg |= t->t_dflg & F_NOINTERRUPT; 692 execute(t->t_dcar, wanttty, NULL, NULL); 693 /* 694 * In strange case of A&B make a new job after A 695 */ 696 if (t->t_dcar->t_dflg & F_AMPERSAND && t->t_dcdr && 697 (t->t_dcdr->t_dflg & F_AMPERSAND) == 0) 698 pendjob(); 699 } 700 if (t->t_dcdr) { 701 t->t_dcdr->t_dflg |= t->t_dflg & 702 (F_NOFORK | F_NOINTERRUPT); 703 execute(t->t_dcdr, wanttty, NULL, NULL); 704 } 705 break; 706 707 case NODE_OR: 708 case NODE_AND: 709 if (t->t_dcar) { 710 t->t_dcar->t_dflg |= t->t_dflg & F_NOINTERRUPT; 711 execute(t->t_dcar, wanttty, NULL, NULL); 712 if ((getn(varval(STRstatus)) == 0) != 713 (t->t_dtyp == NODE_AND)) { 714 return; 715 } 716 } 717 if (t->t_dcdr) { 718 t->t_dcdr->t_dflg |= t->t_dflg & 719 (F_NOFORK | F_NOINTERRUPT); 720 execute(t->t_dcdr, wanttty, NULL, NULL); 721 } 722 break; 723 724 default: 725 break; 726 } 727 /* 728 * Fall through for all breaks from switch 729 * 730 * If there will be no more executions of this command, flush all file 731 * descriptors. Places that turn on the F_REPEAT bit are responsible for 732 * doing donefds after the last re-execution 733 */ 734 if (didfds && !(t->t_dflg & F_REPEAT)) 735 donefds(); 736} 737 738#ifdef VFORK 739static sigret_t 740/*ARGSUSED*/ 741vffree(snum) 742int snum; 743{ 744 register Char **v; 745 746 USE(snum); 747 if ((v = gargv) != 0) { 748 gargv = 0; 749 xfree((ptr_t) v); 750 } 751 752 if ((v = pargv) != 0) { 753 pargv = 0; 754 xfree((ptr_t) v); 755 } 756 757 _exit(1); 758#ifndef SIGVOID 759 /*NOTREACHED*/ 760 return(0); 761#endif /* SIGVOID */ 762} 763#endif /* VFORK */ 764 765/* 766 * Expand and glob the words after an i/o redirection. 767 * If more than one word is generated, then update the command vector. 768 * 769 * This is done differently in all the shells: 770 * 1. in the bourne shell and ksh globbing is not performed 771 * 2. Bash/csh say ambiguous 772 * 3. zsh does i/o to/from all the files 773 * 4. itcsh concatenates the words. 774 * 775 * I don't know what is best to do. I think that Ambiguous is better 776 * than restructuring the command vector, because the user can get 777 * unexpected results. In any case, the command vector restructuring 778 * code is present and the user can choose it by setting noambiguous 779 */ 780static Char * 781splicepipe(t, cp) 782 register struct command *t; 783 Char *cp; /* word after < or > */ 784{ 785 Char *blk[2]; 786 787 if (adrof(STRnoambiguous)) { 788 Char **pv; 789 790 blk[0] = Dfix1(cp); /* expand $ */ 791 blk[1] = NULL; 792 793 gflag = 0, tglob(blk); 794 if (gflag) { 795 pv = globall(blk); 796 if (pv == NULL) { 797 setname(short2str(blk[0])); 798 xfree((ptr_t) blk[0]); 799 stderror(ERR_NAME | ERR_NOMATCH); 800 } 801 gargv = NULL; 802 if (pv[1] != NULL) { /* we need to fix the command vector */ 803 Char **av = blkspl(t->t_dcom, &pv[1]); 804 xfree((ptr_t) t->t_dcom); 805 t->t_dcom = av; 806 } 807 xfree((ptr_t) blk[0]); 808 blk[0] = pv[0]; 809 xfree((ptr_t) pv); 810 } 811 } 812 else { 813 Char buf[BUFSIZE]; 814 815 (void) Strcpy(buf, blk[1] = Dfix1(cp)); 816 xfree((ptr_t) blk[1]); 817 blk[0] = globone(buf, G_ERROR); 818 } 819 return(blk[0]); 820} 821 822/* 823 * Perform io redirection. 824 * We may or maynot be forked here. 825 */ 826static void 827doio(t, pipein, pipeout) 828 register struct command *t; 829 int *pipein, *pipeout; 830{ 831 register int fd; 832 register Char *cp; 833 register unsigned long flags = t->t_dflg; 834 835 if (didfds || (flags & F_REPEAT)) 836 return; 837 if ((flags & F_READ) == 0) {/* F_READ already done */ 838 if (t->t_dlef) { 839 char tmp[MAXPATHLEN+1]; 840 841 /* 842 * so < /dev/std{in,out,err} work 843 */ 844 (void) dcopy(SHIN, 0); 845 (void) dcopy(SHOUT, 1); 846 (void) dcopy(SHDIAG, 2); 847 cp = splicepipe(t, t->t_dlef); 848 (void) strncpy(tmp, short2str(cp), MAXPATHLEN); 849 tmp[MAXPATHLEN] = '\0'; 850 xfree((ptr_t) cp); 851 if ((fd = open(tmp, O_RDONLY)) < 0) 852 stderror(ERR_SYSTEM, tmp, strerror(errno)); 853#ifdef O_LARGEFILE 854 /* allow input files larger than 2Gb */ 855 (void) fcntl(fd, O_LARGEFILE, 0); 856#endif /* O_LARGEFILE */ 857 (void) dmove(fd, 0); 858 } 859 else if (flags & F_PIPEIN) { 860 (void) close(0); 861 (void) dup(pipein[0]); 862 (void) close(pipein[0]); 863 (void) close(pipein[1]); 864 } 865 else if ((flags & F_NOINTERRUPT) && tpgrp == -1) { 866 (void) close(0); 867 (void) open(_PATH_DEVNULL, O_RDONLY); 868 } 869 else { 870 (void) close(0); 871 (void) dup(OLDSTD); 872#if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 873 /* 874 * PWP: Unlike Bezerkeley 4.3, FIONCLEX for Pyramid is preserved 875 * across dup()s, so we have to UNSET it here or else we get a 876 * command with NO stdin, stdout, or stderr at all (a bad thing 877 * indeed) 878 */ 879 (void) close_on_exec(0, 0); 880#endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 881 } 882 } 883 if (t->t_drit) { 884 char tmp[MAXPATHLEN+1]; 885 886 cp = splicepipe(t, t->t_drit); 887 (void) strncpy(tmp, short2str(cp), MAXPATHLEN); 888 tmp[MAXPATHLEN] = '\0'; 889 xfree((ptr_t) cp); 890 /* 891 * so > /dev/std{out,err} work 892 */ 893 (void) dcopy(SHOUT, 1); 894 (void) dcopy(SHDIAG, 2); 895 if ((flags & F_APPEND) != 0) { 896#ifdef O_APPEND 897 fd = open(tmp, O_WRONLY | O_APPEND); 898#else /* !O_APPEND */ 899 fd = open(tmp, O_WRONLY); 900 (void) lseek(fd, (off_t) 0, L_XTND); 901#endif /* O_APPEND */ 902 } 903 else 904 fd = 0; 905 if ((flags & F_APPEND) == 0 || fd == -1) { 906 if (!(flags & F_OVERWRITE) && adrof(STRnoclobber)) { 907 if (flags & F_APPEND) 908 stderror(ERR_SYSTEM, tmp, strerror(errno)); 909 chkclob(tmp); 910 } 911 if ((fd = creat(tmp, 0666)) < 0) 912 stderror(ERR_SYSTEM, tmp, strerror(errno)); 913#ifdef O_LARGEFILE 914 /* allow input files larger than 2Gb */ 915 (void) fcntl(fd, O_LARGEFILE, 0); 916#endif /* O_LARGEFILE */ 917 } 918 (void) dmove(fd, 1); 919 is1atty = isatty(1); 920 } 921 else if (flags & F_PIPEOUT) { 922 (void) close(1); 923 (void) dup(pipeout[1]); 924 is1atty = 0; 925 } 926 else { 927 (void) close(1); 928 (void) dup(SHOUT); 929 is1atty = isoutatty; 930# if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 931 (void) close_on_exec(1, 0); 932# endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 933 } 934 935 (void) close(2); 936 if (flags & F_STDERR) { 937 (void) dup(1); 938 is2atty = is1atty; 939 } 940 else { 941 (void) dup(SHDIAG); 942 is2atty = isdiagatty; 943# if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 944 (void) close_on_exec(2, 0); 945# endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 946 } 947 didfds = 1; 948} 949 950void 951mypipe(pv) 952 register int *pv; 953{ 954 955 if (pipe(pv) < 0) 956 goto oops; 957 pv[0] = dmove(pv[0], -1); 958 pv[1] = dmove(pv[1], -1); 959 if (pv[0] >= 0 && pv[1] >= 0) 960 return; 961oops: 962 stderror(ERR_PIPE); 963} 964 965static void 966chkclob(cp) 967 register char *cp; 968{ 969 struct stat stb; 970 971 if (stat(cp, &stb) < 0) 972 return; 973 if (S_ISCHR(stb.st_mode)) 974 return; 975 stderror(ERR_EXISTS, cp); 976} 977