sh.sem.c revision 225736
1/* $Header: /p/tcsh/cvsroot/tcsh/sh.sem.c,v 3.80 2009/06/25 21:27:38 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. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34#include "sh.h" 35 36RCSID("$tcsh: sh.sem.c,v 3.80 2009/06/25 21:27:38 christos Exp $") 37 38#include "tc.h" 39#include "tw.h" 40#ifdef WINNT_NATIVE 41#include "nt.const.h" 42#endif /*WINNT_NATIVE*/ 43 44#ifdef CLOSE_ON_EXEC 45# ifndef SUNOS4 46# ifndef CLEX_DUPS 47# define CLEX_DUPS 48# endif /* CLEX_DUPS */ 49# endif /* !SUNOS4 */ 50#endif /* CLOSE_ON_EXEC */ 51 52#if defined(__sparc__) || defined(sparc) 53# if !defined(MACH) && SYSVREL == 0 && !defined(Lynx) && !defined(BSD4_4) && !defined(linux) && !defined(__GNU__) && !defined(__GLIBC__) 54# include <vfork.h> 55# endif /* !MACH && SYSVREL == 0 && !Lynx && !BSD4_4 && !glibc */ 56#endif /* __sparc__ || sparc */ 57 58#ifdef VFORK 59static void vffree (int); 60#endif 61static Char *splicepipe (struct command *, Char *); 62static void doio (struct command *, int *, int *); 63static void chkclob (const char *); 64 65/* 66 * C shell 67 */ 68 69/* 70 * For SVR4, there are problems with pipelines having the first process as 71 * the group leader. The problem occurs when the first process exits before 72 * the others have a chance to setpgid(). This is because in SVR4 you can't 73 * have a zombie as a group leader. The solution I have used is to reverse 74 * the order in which pipelines are started, making the last process the 75 * group leader. (Note I am not using 'pipeline' in the generic sense -- I 76 * mean processes connected by '|'.) I don't know yet if this causes other 77 * problems. 78 * 79 * All the changes for this are in execute(), and are enclosed in 80 * '#ifdef BACKPIPE' 81 * 82 * David Dawes (dawes@physics.su.oz.au) Oct 1991 83 */ 84 85/*VARARGS 1*/ 86void 87execute(struct command *t, volatile int wanttty, int *pipein, int *pipeout, 88 int do_glob) 89{ 90 int forked = 0; 91 const struct biltins * volatile bifunc; 92 pid_t pid = 0; 93 int pv[2]; 94 sigset_t set; 95 static sigset_t csigset; 96#ifdef VFORK 97 static int onosigchld = 0; 98#endif /* VFORK */ 99 static int nosigchld = 0; 100 101 (void) &wanttty; 102 (void) &forked; 103 (void) &bifunc; 104 105 if (t == 0) 106 return; 107 108#ifdef WINNT_NATIVE 109 { 110 if ((varval(STRNTslowexec) == STRNULL) && 111 !t->t_dcdr && !t->t_dcar && !t->t_dflg && !didfds && 112 (intty || intact) && (t->t_dtyp == NODE_COMMAND) && 113 !isbfunc(t)) { 114 if ((t->t_dcom[0][0] & (QUOTE | TRIM)) == QUOTE) 115 (void) Strcpy(t->t_dcom[0], t->t_dcom[0] + 1); 116 Dfix(t); 117 if (nt_try_fast_exec(t) == 0) 118 return; 119 } 120 } 121#endif /* WINNT_NATIVE */ 122 123 /* 124 * Ed hutchins@sgi.com & Dominic dbg@sgi.com 125 * Sat Feb 25 03:13:11 PST 1995 126 * try implicit cd if we have a 1 word command 127 */ 128 if (implicit_cd && (intty || intact) && t->t_dcom && t->t_dcom[0] && 129 t->t_dcom[0][0] && (blklen(t->t_dcom) == 1) && !noexec) { 130 Char *sCName; 131 struct stat stbuf; 132 char *pathname; 133 134 sCName = dollar(t->t_dcom[0]); 135 if (sCName != NULL && sCName[0] == '~') { 136 struct Strbuf buf = Strbuf_INIT; 137 const Char *name_end; 138 139 for (name_end = sCName + 1; *name_end != '\0' && *name_end != '/'; 140 name_end++) 141 continue; 142 if (name_end != sCName + 1) { 143 Char *name, *home; 144 145 name = Strnsave(sCName + 1, name_end - (sCName + 1)); 146 home = gethdir(name); 147 if (home != NULL) { 148 Strbuf_append(&buf, home); 149 xfree(home); 150 } else 151 Strbuf_append(&buf, name); 152 xfree(name); 153 } else 154 Strbuf_append(&buf, varval(STRhome)); 155 Strbuf_append(&buf, name_end); 156 xfree(sCName); 157 sCName = Strbuf_finish(&buf); 158 } 159 160 pathname = short2str(sCName); 161 xfree(sCName); 162 /* if this is a dir, tack a "cd" on as the first arg */ 163 if (pathname != NULL && 164 ((stat(pathname, &stbuf) != -1 && S_ISDIR(stbuf.st_mode)) 165#ifdef WINNT_NATIVE 166 || (pathname[0] && pathname[1] == ':' && pathname[2] == '\0') 167#endif /* WINNT_NATIVE */ 168 )) { 169 Char *vCD[2]; 170 Char **ot_dcom = t->t_dcom; 171 172 vCD[0] = Strsave(STRcd); 173 vCD[1] = NULL; 174 t->t_dcom = blkspl(vCD, ot_dcom); 175 xfree(ot_dcom); 176 if (implicit_cd > 1) { 177 blkpr(t->t_dcom); 178 xputchar( '\n' ); 179 } 180 } 181 } 182 183 /* 184 * From: Michael Schroeder <mlschroe@immd4.informatik.uni-erlangen.de> 185 * Don't check for wantty > 0... 186 */ 187 if (t->t_dflg & F_AMPERSAND) 188 wanttty = 0; 189 switch (t->t_dtyp) { 190 191 case NODE_COMMAND: 192 if ((t->t_dcom[0][0] & (QUOTE | TRIM)) == QUOTE) 193 memmove(t->t_dcom[0], t->t_dcom[0] + 1, 194 (Strlen(t->t_dcom[0] + 1) + 1) * sizeof (*t->t_dcom[0])); 195 if ((t->t_dflg & F_REPEAT) == 0) 196 Dfix(t); /* $ " ' \ */ 197 if (t->t_dcom[0] == 0) { 198 return; 199 } 200 /*FALLTHROUGH*/ 201 202 case NODE_PAREN: 203#ifdef BACKPIPE 204 if (t->t_dflg & F_PIPEIN) 205 mypipe(pipein); 206#else /* !BACKPIPE */ 207 if (t->t_dflg & F_PIPEOUT) 208 mypipe(pipeout); 209#endif /* BACKPIPE */ 210 /* 211 * Must do << early so parent will know where input pointer should be. 212 * If noexec then this is all we do. 213 */ 214 if (t->t_dflg & F_READ) { 215 xclose(0); 216 heredoc(t->t_dlef); 217 if (noexec) 218 xclose(0); 219 } 220 221 setcopy(STRstatus, STR0, VAR_READWRITE); 222 223 /* 224 * This mess is the necessary kludge to handle the prefix builtins: 225 * nice, nohup, time. These commands can also be used by themselves, 226 * and this is not handled here. This will also work when loops are 227 * parsed. 228 */ 229 while (t->t_dtyp == NODE_COMMAND) 230 if (eq(t->t_dcom[0], STRnice)) { 231 if (t->t_dcom[1]) { 232 if (strchr("+-", t->t_dcom[1][0])) { 233 if (t->t_dcom[2]) { 234 setname("nice"); 235 t->t_nice = 236 getn(t->t_dcom[1]); 237 lshift(t->t_dcom, 2); 238 t->t_dflg |= F_NICE; 239 } 240 else 241 break; 242 } 243 else { 244 t->t_nice = 4; 245 lshift(t->t_dcom, 1); 246 t->t_dflg |= F_NICE; 247 } 248 } 249 else 250 break; 251 } 252 else if (eq(t->t_dcom[0], STRnohup)) { 253 if (t->t_dcom[1]) { 254 t->t_dflg |= F_NOHUP; 255 lshift(t->t_dcom, 1); 256 } 257 else 258 break; 259 } 260 else if (eq(t->t_dcom[0], STRhup)) { 261 if (t->t_dcom[1]) { 262 t->t_dflg |= F_HUP; 263 lshift(t->t_dcom, 1); 264 } 265 else 266 break; 267 } 268 else if (eq(t->t_dcom[0], STRtime)) { 269 if (t->t_dcom[1]) { 270 t->t_dflg |= F_TIME; 271 lshift(t->t_dcom, 1); 272 } 273 else 274 break; 275 } 276#ifdef F_VER 277 else if (eq(t->t_dcom[0], STRver)) 278 if (t->t_dcom[1] && t->t_dcom[2]) { 279 setname("ver"); 280 t->t_systype = getv(t->t_dcom[1]); 281 lshift(t->t_dcom, 2); 282 t->t_dflg |= F_VER; 283 } 284 else 285 break; 286#endif /* F_VER */ 287 else 288 break; 289 290 /* is it a command */ 291 if (t->t_dtyp == NODE_COMMAND) { 292 /* 293 * Check if we have a builtin function and remember which one. 294 */ 295 bifunc = isbfunc(t); 296 if (noexec) { 297 /* 298 * Continue for builtins that are part of the scripting language 299 */ 300 if (bifunc == NULL) 301 break; 302 if (bifunc->bfunct != (bfunc_t)dobreak && 303 bifunc->bfunct != (bfunc_t)docontin && 304 bifunc->bfunct != (bfunc_t)doelse && 305 bifunc->bfunct != (bfunc_t)doend && 306 bifunc->bfunct != (bfunc_t)doforeach&& 307 bifunc->bfunct != (bfunc_t)dogoto && 308 bifunc->bfunct != (bfunc_t)doif && 309 bifunc->bfunct != (bfunc_t)dorepeat && 310 bifunc->bfunct != (bfunc_t)doswbrk && 311 bifunc->bfunct != (bfunc_t)doswitch && 312 bifunc->bfunct != (bfunc_t)dowhile && 313 bifunc->bfunct != (bfunc_t)dozip) 314 break; 315 } 316 } 317 else { /* not a command */ 318 bifunc = NULL; 319 if (noexec) 320 break; 321 } 322 323 /* 324 * GrP Executing a command - run jobcmd hook 325 * Don't run for builtins 326 * Don't run if we're not in a tty 327 * Don't run if we're not really executing 328 */ 329 /* 330 * CR - Charles Ross Aug 2005 331 * added "isoutatty". 332 * The new behavior is that the jobcmd won't be executed 333 * if stdout (SHOUT) isnt attached to a tty.. IE when 334 * redirecting, or using backquotes etc.. 335 */ 336 if (t->t_dtyp == NODE_COMMAND && !bifunc && !noexec && intty && isoutatty) { 337 Char *cmd = unparse(t); 338 339 cleanup_push(cmd, xfree); 340 job_cmd(cmd); 341 cleanup_until(cmd); 342 } 343 344 /* 345 * We fork only if we are timed, or are not the end of a parenthesized 346 * list and not a simple builtin function. Simple meaning one that is 347 * not pipedout, niced, nohupped, or &'d. It would be nice(?) to not 348 * fork in some of these cases. 349 */ 350 /* 351 * Prevent forking cd, pushd, popd, chdir cause this will cause the 352 * shell not to change dir! 353 */ 354#ifdef BACKPIPE 355 /* 356 * Can't have NOFORK for the tail of a pipe - because it is not the 357 * last command spawned (even if it is at the end of a parenthesised 358 * list). 359 */ 360 if (t->t_dflg & F_PIPEIN) 361 t->t_dflg &= ~(F_NOFORK); 362#endif /* BACKPIPE */ 363 if (bifunc && (bifunc->bfunct == (bfunc_t)dochngd || 364 bifunc->bfunct == (bfunc_t)dopushd || 365 bifunc->bfunct == (bfunc_t)dopopd)) 366 t->t_dflg &= ~(F_NICE); 367 if (((t->t_dflg & F_TIME) || ((t->t_dflg & F_NOFORK) == 0 && 368 (!bifunc || t->t_dflg & 369 (F_PIPEOUT | F_AMPERSAND | F_NICE | F_NOHUP | F_HUP)))) || 370 /* 371 * We have to fork for eval too. 372 */ 373 (bifunc && (t->t_dflg & F_PIPEIN) != 0 && 374 bifunc->bfunct == (bfunc_t)doeval)) { 375#ifdef VFORK 376 if (t->t_dtyp == NODE_PAREN || 377 t->t_dflg & (F_REPEAT | F_AMPERSAND) || bifunc) 378#endif /* VFORK */ 379 { 380 forked++; 381 /* 382 * We need to block SIGCHLD here, so that if the process does 383 * not die before we can set the process group 384 */ 385 if (wanttty >= 0 && !nosigchld) { 386 sigemptyset(&set); 387 sigaddset(&set, SIGCHLD); 388 (void)sigprocmask(SIG_BLOCK, &set, &csigset); 389 390 nosigchld = 1; 391 } 392 393 pid = pfork(t, wanttty); 394 if (pid == 0 && nosigchld) { 395 sigprocmask(SIG_SETMASK, &csigset, NULL); 396 nosigchld = 0; 397 } 398 else if (pid != 0 && (t->t_dflg & F_AMPERSAND)) 399 backpid = pid; 400 } 401 402#ifdef VFORK 403 else { 404 int ochild, osetintr, ohaderr, odidfds; 405 int oSHIN, oSHOUT, oSHDIAG, oOLDSTD, otpgrp; 406 int oisoutatty, oisdiagatty; 407 sigset_t oset, ocsigset; 408# ifndef CLOSE_ON_EXEC 409 int odidcch; 410# endif /* !CLOSE_ON_EXEC */ 411 412 /* 413 * Prepare for the vfork by saving everything that the child 414 * corrupts before it exec's. Note that in some signal 415 * implementations which keep the signal info in user space 416 * (e.g. Sun's) it will also be necessary to save and restore 417 * the current sigvec's for the signals the child touches 418 * before it exec's. 419 */ 420 421 /* 422 * Sooooo true... If this is a Sun, save the sigvec's. (Skip 423 * Gilbrech - 11/22/87) 424 */ 425# ifdef SAVESIGVEC 426 struct sigaction savesv[NSIGSAVED]; 427 sigset_t savesm; 428 429# endif /* SAVESIGVEC */ 430 if (wanttty >= 0 && !nosigchld && !noexec) { 431 sigemptyset(&set); 432 sigaddset(&set, SIGCHLD); 433 (void)sigprocmask(SIG_BLOCK, &set, &csigset); 434 nosigchld = 1; 435 } 436 sigemptyset(&set); 437 sigaddset(&set, SIGCHLD); 438 sigaddset(&set, SIGINT); 439 (void)sigprocmask(SIG_BLOCK, &set, &oset); 440 ochild = child; 441 osetintr = setintr; 442 ohaderr = haderr; 443 odidfds = didfds; 444# ifndef CLOSE_ON_EXEC 445 odidcch = didcch; 446# endif /* !CLOSE_ON_EXEC */ 447 oSHIN = SHIN; 448 oSHOUT = SHOUT; 449 oSHDIAG = SHDIAG; 450 oOLDSTD = OLDSTD; 451 otpgrp = tpgrp; 452 oisoutatty = isoutatty; 453 oisdiagatty = isdiagatty; 454 ocsigset = csigset; 455 onosigchld = nosigchld; 456 Vsav = Vdp = 0; 457 Vexpath = 0; 458 Vt = 0; 459# ifdef SAVESIGVEC 460 savesigvec(savesv, savesm); 461# endif /* SAVESIGVEC */ 462 if (use_fork) 463 pid = fork(); 464 else 465 pid = vfork(); 466 467 if (pid < 0) { 468# ifdef SAVESIGVEC 469 restoresigvec(savesv, savesm); 470# endif /* SAVESIGVEC */ 471 sigprocmask(SIG_SETMASK, &oset, NULL); 472 stderror(ERR_NOPROC); 473 } 474 forked++; 475 if (pid) { /* parent */ 476# ifdef SAVESIGVEC 477 restoresigvec(savesv, savesm); 478# endif /* SAVESIGVEC */ 479 child = ochild; 480 setintr = osetintr; 481 haderr = ohaderr; 482 didfds = odidfds; 483 SHIN = oSHIN; 484# ifndef CLOSE_ON_EXEC 485 didcch = odidcch; 486# endif /* !CLOSE_ON_EXEC */ 487 SHOUT = oSHOUT; 488 SHDIAG = oSHDIAG; 489 OLDSTD = oOLDSTD; 490 tpgrp = otpgrp; 491 isoutatty = oisoutatty; 492 isdiagatty = oisdiagatty; 493 csigset = ocsigset; 494 nosigchld = onosigchld; 495 496 xfree(Vsav); 497 Vsav = 0; 498 xfree(Vdp); 499 Vdp = 0; 500 xfree(Vexpath); 501 Vexpath = 0; 502 blk_cleanup(Vt); 503 Vt = 0; 504 /* this is from pfork() */ 505 palloc(pid, t); 506 sigprocmask(SIG_SETMASK, &oset, NULL); 507 } 508 else { /* child */ 509 /* this is from pfork() */ 510 pid_t pgrp; 511 int ignint = 0; 512 if (nosigchld) { 513 sigprocmask(SIG_SETMASK, &csigset, NULL); 514 nosigchld = 0; 515 } 516 517 if (setintr) 518 ignint = (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT)) 519 || (gointr && eq(gointr, STRminus)); 520 pgrp = pcurrjob ? pcurrjob->p_jobid : getpid(); 521 child++; 522 if (setintr) { 523 setintr = 0; 524/* 525 * casts made right for SunOS 4.0 by Douglas C. Schmidt 526 * <schmidt%sunshine.ics.uci.edu@ROME.ICS.UCI.EDU> 527 * (thanks! -- PWP) 528 * 529 * ignint ifs cleaned by Johan Widen <mcvax!osiris.sics.se!jw@uunet.UU.NET> 530 * (thanks again) 531 */ 532 if (ignint) { 533 (void) signal(SIGINT, SIG_IGN); 534 (void) signal(SIGQUIT, SIG_IGN); 535 } 536 else { 537 (void) signal(SIGINT, vffree); 538 (void) signal(SIGQUIT, SIG_DFL); 539 } 540# ifdef BSDJOBS 541 if (wanttty >= 0) { 542 (void) signal(SIGTSTP, SIG_DFL); 543 (void) signal(SIGTTIN, SIG_DFL); 544 (void) signal(SIGTTOU, SIG_DFL); 545 } 546# endif /* BSDJOBS */ 547 548 sigaction(SIGTERM, &parterm, NULL); 549 } 550 else if (tpgrp == -1 && 551 (t->t_dflg & F_NOINTERRUPT)) { 552 (void) signal(SIGINT, SIG_IGN); 553 (void) signal(SIGQUIT, SIG_IGN); 554 } 555 556 pgetty(wanttty, pgrp); 557 558 if (t->t_dflg & F_NOHUP) 559 (void) signal(SIGHUP, SIG_IGN); 560 if (t->t_dflg & F_HUP) 561 (void) signal(SIGHUP, SIG_DFL); 562 if (t->t_dflg & F_NICE) { 563 int nval = SIGN_EXTEND_CHAR(t->t_nice); 564# ifdef HAVE_SETPRIORITY 565 if (setpriority(PRIO_PROCESS, 0, nval) == -1 && errno) 566 stderror(ERR_SYSTEM, "setpriority", 567 strerror(errno)); 568# else /* !HAVE_SETPRIORITY */ 569 (void) nice(nval); 570# endif /* HAVE_SETPRIORITY */ 571 } 572# ifdef F_VER 573 if (t->t_dflg & F_VER) { 574 tsetenv(STRSYSTYPE, t->t_systype ? STRbsd43 : STRsys53); 575 dohash(NULL, NULL); 576 } 577# endif /* F_VER */ 578 } 579 580 } 581#endif /* VFORK */ 582 } 583 if (pid != 0) { 584 /* 585 * It would be better if we could wait for the whole job when we 586 * knew the last process had been started. Pwait, in fact, does 587 * wait for the whole job anyway, but this test doesn't really 588 * express our intentions. 589 */ 590#ifdef BACKPIPE 591 if (didfds == 0 && t->t_dflg & F_PIPEOUT) { 592 xclose(pipeout[0]); 593 xclose(pipeout[1]); 594 } 595 if ((t->t_dflg & F_PIPEIN) != 0) 596 break; 597#else /* !BACKPIPE */ 598 if (didfds == 0 && t->t_dflg & F_PIPEIN) { 599 xclose(pipein[0]); 600 xclose(pipein[1]); 601 } 602 if ((t->t_dflg & F_PIPEOUT) != 0) 603 break; 604#endif /* BACKPIPE */ 605 606 if (nosigchld) { 607 sigprocmask(SIG_SETMASK, &csigset, NULL); 608 nosigchld = 0; 609 } 610 if ((t->t_dflg & F_AMPERSAND) == 0) 611 pwait(); 612 break; 613 } 614 615 doio(t, pipein, pipeout); 616#ifdef BACKPIPE 617 if (t->t_dflg & F_PIPEIN) { 618 xclose(pipein[0]); 619 xclose(pipein[1]); 620 } 621#else /* !BACKPIPE */ 622 if (t->t_dflg & F_PIPEOUT) { 623 xclose(pipeout[0]); 624 xclose(pipeout[1]); 625 } 626#endif /* BACKPIPE */ 627 /* 628 * Perform a builtin function. If we are not forked, arrange for 629 * possible stopping 630 */ 631 if (bifunc) { 632 func(t, bifunc); 633 if (forked) 634 exitstat(); 635 else { 636 if (adrof(STRprintexitvalue)) { 637 int rv = getn(varval(STRstatus)); 638 if (rv != 0) 639 xprintf(CGETS(17, 2, "Exit %d\n"), rv); 640 } 641 } 642 break; 643 } 644 if (t->t_dtyp != NODE_PAREN) { 645 doexec(t, do_glob); 646 /* NOTREACHED */ 647 } 648 /* 649 * For () commands must put new 0,1,2 in FSH* and recurse 650 */ 651 (void)close_on_exec(OLDSTD = dcopy(0, FOLDSTD), 1); 652 (void)close_on_exec(SHOUT = dcopy(1, FSHOUT), 1); 653 isoutatty = isatty(SHOUT); 654 (void)close_on_exec(SHDIAG = dcopy(2, FSHDIAG), 1); 655 isdiagatty = isatty(SHDIAG); 656 xclose(SHIN); 657 SHIN = -1; 658#ifndef CLOSE_ON_EXEC 659 didcch = 0; 660#else 661 (void) close_on_exec(FSHOUT, 1); 662 (void) close_on_exec(FSHDIAG, 1); 663 (void) close_on_exec(FOLDSTD, 1); 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, do_glob); 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, do_glob); 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, do_glob); 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, do_glob); 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, do_glob); 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, do_glob); 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, do_glob); 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, do_glob); 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, do_glob); 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 void 740/*ARGSUSED*/ 741vffree(int snum) 742{ 743 USE(snum); 744 745 _exit(1); 746} 747#endif /* VFORK */ 748 749/* 750 * Expand and glob the words after an i/o redirection. 751 * If more than one word is generated, then update the command vector. 752 * 753 * This is done differently in all the shells: 754 * 1. in the bourne shell and ksh globbing is not performed 755 * 2. Bash/csh say ambiguous 756 * 3. zsh does i/o to/from all the files 757 * 4. itcsh concatenates the words. 758 * 759 * I don't know what is best to do. I think that Ambiguous is better 760 * than restructuring the command vector, because the user can get 761 * unexpected results. In any case, the command vector restructuring 762 * code is present and the user can choose it by setting noambiguous 763 */ 764static Char * 765splicepipe(struct command *t, Char *cp) 766{ 767 Char *blk[2]; 768 769 if (adrof(STRnoambiguous)) { 770 Char **pv; 771 int gflag; 772 773 blk[0] = Dfix1(cp); /* expand $ */ 774 blk[1] = NULL; 775 776 gflag = tglob(blk); 777 if (gflag) { 778 pv = globall(blk, gflag); 779 if (pv == NULL) { 780 setname(short2str(blk[0])); 781 xfree(blk[0]); 782 stderror(ERR_NAME | ERR_NOMATCH); 783 } 784 if (pv[1] != NULL) { /* we need to fix the command vector */ 785 Char **av = blkspl(t->t_dcom, &pv[1]); 786 xfree(t->t_dcom); 787 t->t_dcom = av; 788 } 789 xfree(blk[0]); 790 blk[0] = pv[0]; 791 xfree(pv); 792 } 793 } 794 else { 795 Char *buf; 796 797 buf = Dfix1(cp); 798 cleanup_push(buf, xfree); 799 blk[0] = globone(buf, G_ERROR); 800 cleanup_until(buf); 801 } 802 return(blk[0]); 803} 804 805/* 806 * Perform io redirection. 807 * We may or maynot be forked here. 808 */ 809static void 810doio(struct command *t, int *pipein, int *pipeout) 811{ 812 int fd; 813 Char *cp; 814 unsigned long flags = t->t_dflg; 815 816 if (didfds || (flags & F_REPEAT)) 817 return; 818 if ((flags & F_READ) == 0) {/* F_READ already done */ 819 if (t->t_dlef) { 820 char *tmp; 821 822 /* 823 * so < /dev/std{in,out,err} work 824 */ 825 (void) dcopy(SHIN, 0); 826 (void) dcopy(SHOUT, 1); 827 (void) dcopy(SHDIAG, 2); 828 cp = splicepipe(t, t->t_dlef); 829 tmp = strsave(short2str(cp)); 830 xfree(cp); 831 cleanup_push(tmp, xfree); 832 if ((fd = xopen(tmp, O_RDONLY|O_LARGEFILE)) < 0) 833 stderror(ERR_SYSTEM, tmp, strerror(errno)); 834 cleanup_until(tmp); 835 /* allow input files larger than 2Gb */ 836#ifndef WINNT_NATIVE 837 (void) fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_LARGEFILE); 838#endif /*!WINNT_NATIVE*/ 839 (void) dmove(fd, 0); 840 } 841 else if (flags & F_PIPEIN) { 842 xclose(0); 843 IGNORE(dup(pipein[0])); 844 xclose(pipein[0]); 845 xclose(pipein[1]); 846 } 847 else if ((flags & F_NOINTERRUPT) && tpgrp == -1) { 848 xclose(0); 849 (void) xopen(_PATH_DEVNULL, O_RDONLY|O_LARGEFILE); 850 } 851 else { 852 xclose(0); 853 IGNORE(dup(OLDSTD)); 854#if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 855 /* 856 * PWP: Unlike Bezerkeley 4.3, FIONCLEX for Pyramid is preserved 857 * across dup()s, so we have to UNSET it here or else we get a 858 * command with NO stdin, stdout, or stderr at all (a bad thing 859 * indeed) 860 */ 861 (void) close_on_exec(0, 0); 862#endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 863 } 864 } 865 if (t->t_drit) { 866 char *tmp; 867 868 cp = splicepipe(t, t->t_drit); 869 tmp = strsave(short2str(cp)); 870 xfree(cp); 871 cleanup_push(tmp, xfree); 872 /* 873 * so > /dev/std{out,err} work 874 */ 875 (void) dcopy(SHOUT, 1); 876 (void) dcopy(SHDIAG, 2); 877 if ((flags & F_APPEND) != 0) { 878#ifdef O_APPEND 879 fd = xopen(tmp, O_WRONLY|O_APPEND|O_LARGEFILE); 880#else /* !O_APPEND */ 881 fd = xopen(tmp, O_WRONLY|O_LARGEFILE); 882 (void) lseek(fd, (off_t) 0, L_XTND); 883#endif /* O_APPEND */ 884 } 885 else 886 fd = 0; 887 if ((flags & F_APPEND) == 0 || fd == -1) { 888 if (!(flags & F_OVERWRITE) && adrof(STRnoclobber)) { 889 if (flags & F_APPEND) 890 stderror(ERR_SYSTEM, tmp, strerror(errno)); 891 chkclob(tmp); 892 } 893 if ((fd = xcreat(tmp, 0666)) < 0) 894 stderror(ERR_SYSTEM, tmp, strerror(errno)); 895 /* allow input files larger than 2Gb */ 896#ifndef WINNT_NATIVE 897 (void) fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_LARGEFILE); 898#endif /*!WINNT_NATIVE*/ 899 } 900 cleanup_until(tmp); 901 (void) dmove(fd, 1); 902 is1atty = isatty(1); 903 } 904 else if (flags & F_PIPEOUT) { 905 xclose(1); 906 IGNORE(dup(pipeout[1])); 907 is1atty = 0; 908 } 909 else { 910 xclose(1); 911 IGNORE(dup(SHOUT)); 912 is1atty = isoutatty; 913# if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 914 (void) close_on_exec(1, 0); 915# endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 916 } 917 918 xclose(2); 919 if (flags & F_STDERR) { 920 IGNORE(dup(1)); 921 is2atty = is1atty; 922 } 923 else { 924 IGNORE(dup(SHDIAG)); 925 is2atty = isdiagatty; 926# if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 927 (void) close_on_exec(2, 0); 928# endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 929 } 930 didfds = 1; 931} 932 933void 934mypipe(int *pv) 935{ 936 937 if (pipe(pv) < 0) 938 goto oops; 939 (void)close_on_exec(pv[0] = dmove(pv[0], -1), 1); 940 (void)close_on_exec(pv[1] = dmove(pv[1], -1), 1); 941 if (pv[0] >= 0 && pv[1] >= 0) 942 return; 943 if (pv[0] >= 0) 944 xclose(pv[0]); 945 if (pv[1] >= 0) 946 xclose(pv[1]); 947oops: 948 stderror(ERR_PIPE); 949} 950 951static void 952chkclob(const char *cp) 953{ 954 struct stat stb; 955 956 if (stat(cp, &stb) < 0) 957 return; 958 if (S_ISCHR(stb.st_mode)) 959 return; 960 stderror(ERR_EXISTS, cp); 961} 962