sh.sem.c revision 231990
1/* $Header: /p/tcsh/cvsroot/tcsh/sh.sem.c,v 3.86 2011/02/25 23:24:19 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 3.86 2011/02/25 23:24:19 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 = (unsigned char)getn(t->t_dcom[1]); 236 lshift(t->t_dcom, 2); 237 t->t_dflg |= F_NICE; 238 } 239 else 240 break; 241 } 242 else { 243 t->t_nice = 4; 244 lshift(t->t_dcom, 1); 245 t->t_dflg |= F_NICE; 246 } 247 } 248 else 249 break; 250 } 251 else if (eq(t->t_dcom[0], STRnohup)) { 252 if (t->t_dcom[1]) { 253 t->t_dflg |= F_NOHUP; 254 lshift(t->t_dcom, 1); 255 } 256 else 257 break; 258 } 259 else if (eq(t->t_dcom[0], STRhup)) { 260 if (t->t_dcom[1]) { 261 t->t_dflg |= F_HUP; 262 lshift(t->t_dcom, 1); 263 } 264 else 265 break; 266 } 267 else if (eq(t->t_dcom[0], STRtime)) { 268 if (t->t_dcom[1]) { 269 t->t_dflg |= F_TIME; 270 lshift(t->t_dcom, 1); 271 } 272 else 273 break; 274 } 275#ifdef F_VER 276 else if (eq(t->t_dcom[0], STRver)) 277 if (t->t_dcom[1] && t->t_dcom[2]) { 278 setname("ver"); 279 t->t_systype = getv(t->t_dcom[1]); 280 lshift(t->t_dcom, 2); 281 t->t_dflg |= F_VER; 282 } 283 else 284 break; 285#endif /* F_VER */ 286 else 287 break; 288 289 /* is it a command */ 290 if (t->t_dtyp == NODE_COMMAND) { 291 /* 292 * Check if we have a builtin function and remember which one. 293 */ 294 bifunc = isbfunc(t); 295 if (noexec) { 296 /* 297 * Continue for builtins that are part of the scripting language 298 */ 299 if (bifunc == NULL) 300 break; 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 * GrP Executing a command - run jobcmd hook 324 * Don't run for builtins 325 * Don't run if we're not in a tty 326 * Don't run if we're not really executing 327 */ 328 /* 329 * CR - Charles Ross Aug 2005 330 * added "isoutatty". 331 * The new behavior is that the jobcmd won't be executed 332 * if stdout (SHOUT) isnt attached to a tty.. IE when 333 * redirecting, or using backquotes etc.. 334 */ 335 if (t->t_dtyp == NODE_COMMAND && !bifunc && !noexec && intty && isoutatty) { 336 Char *cmd = unparse(t); 337 338 cleanup_push(cmd, xfree); 339 job_cmd(cmd); 340 cleanup_until(cmd); 341 } 342 343 /* 344 * We fork only if we are timed, or are not the end of a parenthesized 345 * list and not a simple builtin function. Simple meaning one that is 346 * not pipedout, niced, nohupped, or &'d. It would be nice(?) to not 347 * fork in some of these cases. 348 */ 349 /* 350 * Prevent forking cd, pushd, popd, chdir cause this will cause the 351 * shell not to change dir! 352 */ 353#ifdef BACKPIPE 354 /* 355 * Can't have NOFORK for the tail of a pipe - because it is not the 356 * last command spawned (even if it is at the end of a parenthesised 357 * list). 358 */ 359 if (t->t_dflg & F_PIPEIN) 360 t->t_dflg &= ~(F_NOFORK); 361#endif /* BACKPIPE */ 362 if (bifunc && (bifunc->bfunct == (bfunc_t)dochngd || 363 bifunc->bfunct == (bfunc_t)dopushd || 364 bifunc->bfunct == (bfunc_t)dopopd)) 365 t->t_dflg &= ~(F_NICE); 366 if (((t->t_dflg & F_TIME) || ((t->t_dflg & F_NOFORK) == 0 && 367 (!bifunc || t->t_dflg & 368 (F_PIPEOUT | F_AMPERSAND | F_NICE | F_NOHUP | F_HUP)))) || 369 /* 370 * We have to fork for eval too. 371 */ 372 (bifunc && (t->t_dflg & F_PIPEIN) != 0 && 373 bifunc->bfunct == (bfunc_t)doeval)) { 374#ifdef VFORK 375 if (t->t_dtyp == NODE_PAREN || 376 t->t_dflg & (F_REPEAT | F_AMPERSAND) || bifunc) 377#endif /* VFORK */ 378 { 379 forked++; 380 /* 381 * We need to block SIGCHLD here, so that if the process does 382 * not die before we can set the process group 383 */ 384 if (wanttty >= 0 && !nosigchld) { 385 sigemptyset(&set); 386 sigaddset(&set, SIGCHLD); 387 (void)sigprocmask(SIG_BLOCK, &set, &csigset); 388 389 nosigchld = 1; 390 } 391 392 pid = pfork(t, wanttty); 393 if (pid == 0 && nosigchld) { 394 sigprocmask(SIG_SETMASK, &csigset, NULL); 395 nosigchld = 0; 396 } 397 else if (pid != 0 && (t->t_dflg & F_AMPERSAND)) 398 backpid = pid; 399 } 400 401#ifdef VFORK 402 else { 403 int ochild, osetintr, ohaderr, odidfds; 404 int oSHIN, oSHOUT, oSHDIAG, oOLDSTD, otpgrp; 405 int oisoutatty, oisdiagatty; 406 sigset_t oset, ocsigset; 407# ifndef CLOSE_ON_EXEC 408 int odidcch; 409# endif /* !CLOSE_ON_EXEC */ 410 411 /* 412 * Prepare for the vfork by saving everything that the child 413 * corrupts before it exec's. Note that in some signal 414 * implementations which keep the signal info in user space 415 * (e.g. Sun's) it will also be necessary to save and restore 416 * the current sigvec's for the signals the child touches 417 * before it exec's. 418 */ 419 420 /* 421 * Sooooo true... If this is a Sun, save the sigvec's. (Skip 422 * Gilbrech - 11/22/87) 423 */ 424# ifdef SAVESIGVEC 425 struct sigaction savesv[NSIGSAVED]; 426 sigset_t savesm; 427 428# endif /* SAVESIGVEC */ 429 if (wanttty >= 0 && !nosigchld && !noexec) { 430 sigemptyset(&set); 431 sigaddset(&set, SIGCHLD); 432 (void)sigprocmask(SIG_BLOCK, &set, &csigset); 433 nosigchld = 1; 434 } 435 sigemptyset(&set); 436 sigaddset(&set, SIGCHLD); 437 sigaddset(&set, SIGINT); 438 (void)sigprocmask(SIG_BLOCK, &set, &oset); 439 ochild = child; 440 osetintr = setintr; 441 ohaderr = haderr; 442 odidfds = didfds; 443# ifndef CLOSE_ON_EXEC 444 odidcch = didcch; 445# endif /* !CLOSE_ON_EXEC */ 446 oSHIN = SHIN; 447 oSHOUT = SHOUT; 448 oSHDIAG = SHDIAG; 449 oOLDSTD = OLDSTD; 450 otpgrp = tpgrp; 451 oisoutatty = isoutatty; 452 oisdiagatty = isdiagatty; 453 ocsigset = csigset; 454 onosigchld = nosigchld; 455 Vsav = Vdp = 0; 456 Vexpath = 0; 457 Vt = 0; 458# ifdef SAVESIGVEC 459 savesigvec(savesv, savesm); 460# endif /* SAVESIGVEC */ 461 if (use_fork) 462 pid = fork(); 463 else 464 pid = vfork(); 465 466 if (pid < 0) { 467# ifdef SAVESIGVEC 468 restoresigvec(savesv, savesm); 469# endif /* SAVESIGVEC */ 470 sigprocmask(SIG_SETMASK, &oset, NULL); 471 stderror(ERR_NOPROC); 472 } 473 forked++; 474 if (pid) { /* parent */ 475# ifdef SAVESIGVEC 476 restoresigvec(savesv, savesm); 477# endif /* SAVESIGVEC */ 478 child = ochild; 479 setintr = osetintr; 480 haderr = ohaderr; 481 didfds = odidfds; 482 SHIN = oSHIN; 483# ifndef CLOSE_ON_EXEC 484 didcch = odidcch; 485# endif /* !CLOSE_ON_EXEC */ 486 SHOUT = oSHOUT; 487 SHDIAG = oSHDIAG; 488 OLDSTD = oOLDSTD; 489 tpgrp = otpgrp; 490 isoutatty = oisoutatty; 491 isdiagatty = oisdiagatty; 492 csigset = ocsigset; 493 nosigchld = onosigchld; 494 495 xfree(Vsav); 496 Vsav = 0; 497 xfree(Vdp); 498 Vdp = 0; 499 xfree(Vexpath); 500 Vexpath = 0; 501 blk_cleanup(Vt); 502 Vt = 0; 503 /* this is from pfork() */ 504 palloc(pid, t); 505 sigprocmask(SIG_SETMASK, &oset, NULL); 506 } 507 else { /* child */ 508 /* this is from pfork() */ 509 pid_t pgrp; 510 int ignint = 0; 511 if (nosigchld) { 512 sigprocmask(SIG_SETMASK, &csigset, NULL); 513 nosigchld = 0; 514 } 515 516 if (setintr) 517 ignint = (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT)) 518 || (gointr && eq(gointr, STRminus)); 519 pgrp = pcurrjob ? pcurrjob->p_jobid : getpid(); 520 child++; 521 if (setintr) { 522 setintr = 0; 523/* 524 * casts made right for SunOS 4.0 by Douglas C. Schmidt 525 * <schmidt%sunshine.ics.uci.edu@ROME.ICS.UCI.EDU> 526 * (thanks! -- PWP) 527 * 528 * ignint ifs cleaned by Johan Widen <mcvax!osiris.sics.se!jw@uunet.UU.NET> 529 * (thanks again) 530 */ 531 if (ignint) { 532 (void) signal(SIGINT, SIG_IGN); 533 (void) signal(SIGQUIT, SIG_IGN); 534 } 535 else { 536 (void) signal(SIGINT, vffree); 537 (void) signal(SIGQUIT, SIG_DFL); 538 } 539# ifdef BSDJOBS 540 if (wanttty >= 0) { 541 (void) signal(SIGTSTP, SIG_DFL); 542 (void) signal(SIGTTIN, SIG_DFL); 543 (void) signal(SIGTTOU, SIG_DFL); 544 } 545# endif /* BSDJOBS */ 546 547 sigaction(SIGTERM, &parterm, NULL); 548 } 549 else if (tpgrp == -1 && 550 (t->t_dflg & F_NOINTERRUPT)) { 551 (void) signal(SIGINT, SIG_IGN); 552 (void) signal(SIGQUIT, SIG_IGN); 553 } 554 555 pgetty(wanttty, pgrp); 556 557 if (t->t_dflg & F_NOHUP) 558 (void) signal(SIGHUP, SIG_IGN); 559 if (t->t_dflg & F_HUP) 560 (void) signal(SIGHUP, SIG_DFL); 561 if (t->t_dflg & F_NICE) { 562 int nval = SIGN_EXTEND_CHAR(t->t_nice); 563# ifdef HAVE_SETPRIORITY 564 if (setpriority(PRIO_PROCESS, 0, nval) == -1 && errno) 565 stderror(ERR_SYSTEM, "setpriority", 566 strerror(errno)); 567# else /* !HAVE_SETPRIORITY */ 568 (void) nice(nval); 569# endif /* HAVE_SETPRIORITY */ 570 } 571# ifdef F_VER 572 if (t->t_dflg & F_VER) { 573 tsetenv(STRSYSTYPE, t->t_systype ? STRbsd43 : STRsys53); 574 dohash(NULL, NULL); 575 } 576# endif /* F_VER */ 577 } 578 579 } 580#endif /* VFORK */ 581 } 582 if (pid != 0) { 583 /* 584 * It would be better if we could wait for the whole job when we 585 * knew the last process had been started. Pwait, in fact, does 586 * wait for the whole job anyway, but this test doesn't really 587 * express our intentions. 588 */ 589#ifdef BACKPIPE 590 if (didfds == 0 && t->t_dflg & F_PIPEOUT) { 591 xclose(pipeout[0]); 592 xclose(pipeout[1]); 593 } 594 if ((t->t_dflg & F_PIPEIN) != 0) 595 break; 596#else /* !BACKPIPE */ 597 if (didfds == 0 && t->t_dflg & F_PIPEIN) { 598 xclose(pipein[0]); 599 xclose(pipein[1]); 600 } 601 if ((t->t_dflg & F_PIPEOUT) != 0) 602 break; 603#endif /* BACKPIPE */ 604 605 if (nosigchld) { 606 sigprocmask(SIG_SETMASK, &csigset, NULL); 607 nosigchld = 0; 608 } 609 if ((t->t_dflg & F_AMPERSAND) == 0) 610 pwait(); 611 break; 612 } 613 614 doio(t, pipein, pipeout); 615#ifdef BACKPIPE 616 if (t->t_dflg & F_PIPEIN) { 617 xclose(pipein[0]); 618 xclose(pipein[1]); 619 } 620#else /* !BACKPIPE */ 621 if (t->t_dflg & F_PIPEOUT) { 622 xclose(pipeout[0]); 623 xclose(pipeout[1]); 624 } 625#endif /* BACKPIPE */ 626 /* 627 * Perform a builtin function. If we are not forked, arrange for 628 * possible stopping 629 */ 630 if (bifunc) { 631 if (forked) { 632 func(t, bifunc); 633 exitstat(); 634 } else { 635 jmp_buf_t oldexit; 636 int ohaderr = haderr; 637 638 getexit(oldexit); 639 if (setexit() == 0) 640 func(t, bifunc); 641 resexit(oldexit); 642 haderr = ohaderr; 643 644 if (adrof(STRprintexitvalue)) { 645 int rv = getn(varval(STRstatus)); 646 if (rv != 0) 647 xprintf(CGETS(17, 2, "Exit %d\n"), rv); 648 } 649 } 650 break; 651 } 652 if (t->t_dtyp != NODE_PAREN) { 653 doexec(t, do_glob); 654 /* NOTREACHED */ 655 } 656 /* 657 * For () commands must put new 0,1,2 in FSH* and recurse 658 */ 659 if ((OLDSTD = dcopy(0, FOLDSTD)) >= 0) 660 (void)close_on_exec(OLDSTD, 1); 661 if ((SHOUT = dcopy(1, FSHOUT)) >= 0) { 662 (void)close_on_exec(SHOUT, 1); 663 isoutatty = isatty(SHOUT); 664 } 665 if ((SHDIAG = dcopy(2, FSHDIAG)) >= 0) { 666 (void)close_on_exec(SHDIAG, 1); 667 isdiagatty = isatty(SHDIAG); 668 } 669 xclose(SHIN); 670 SHIN = -1; 671#ifndef CLOSE_ON_EXEC 672 didcch = 0; 673#else 674 (void) close_on_exec(FSHOUT, 1); 675 (void) close_on_exec(FSHDIAG, 1); 676 (void) close_on_exec(FOLDSTD, 1); 677#endif /* !CLOSE_ON_EXEC */ 678 didfds = 0; 679 wanttty = -1; 680 t->t_dspr->t_dflg |= t->t_dflg & (F_NOINTERRUPT | F_BACKQ); 681 execute(t->t_dspr, wanttty, NULL, NULL, do_glob); 682 exitstat(); 683 684 case NODE_PIPE: 685#ifdef BACKPIPE 686 t->t_dcdr->t_dflg |= F_PIPEIN | (t->t_dflg & 687 (F_PIPEOUT | F_AMPERSAND | F_NOFORK | F_NOINTERRUPT | F_BACKQ)); 688 execute(t->t_dcdr, wanttty, pv, pipeout, do_glob); 689 t->t_dcar->t_dflg |= F_PIPEOUT | (t->t_dflg & 690 (F_PIPEIN | F_AMPERSAND | F_STDERR | F_NOINTERRUPT | F_BACKQ)); 691 execute(t->t_dcar, wanttty, pipein, pv, do_glob); 692#else /* !BACKPIPE */ 693 t->t_dcar->t_dflg |= F_PIPEOUT | (t->t_dflg & 694 (F_PIPEIN | F_AMPERSAND | F_STDERR | F_NOINTERRUPT | F_BACKQ)); 695 execute(t->t_dcar, wanttty, pipein, pv, do_glob); 696 t->t_dcdr->t_dflg |= F_PIPEIN | (t->t_dflg & 697 (F_PIPEOUT | F_AMPERSAND | F_NOFORK | F_NOINTERRUPT | F_BACKQ)); 698 execute(t->t_dcdr, wanttty, pv, pipeout, do_glob); 699#endif /* BACKPIPE */ 700 break; 701 702 case NODE_LIST: 703 if (t->t_dcar) { 704 t->t_dcar->t_dflg |= t->t_dflg & (F_NOINTERRUPT | F_BACKQ); 705 execute(t->t_dcar, wanttty, NULL, NULL, do_glob); 706 /* 707 * In strange case of A&B make a new job after A 708 */ 709 if (t->t_dcar->t_dflg & F_AMPERSAND && t->t_dcdr && 710 (t->t_dcdr->t_dflg & F_AMPERSAND) == 0) 711 pendjob(); 712 } 713 if (t->t_dcdr) { 714 t->t_dcdr->t_dflg |= t->t_dflg & 715 (F_NOFORK | F_NOINTERRUPT | F_BACKQ); 716 execute(t->t_dcdr, wanttty, NULL, NULL, do_glob); 717 } 718 break; 719 720 case NODE_OR: 721 case NODE_AND: 722 if (t->t_dcar) { 723 t->t_dcar->t_dflg |= t->t_dflg & (F_NOINTERRUPT | F_BACKQ); 724 execute(t->t_dcar, wanttty, NULL, NULL, do_glob); 725 if ((getn(varval(STRstatus)) == 0) != 726 (t->t_dtyp == NODE_AND)) { 727 return; 728 } 729 } 730 if (t->t_dcdr) { 731 t->t_dcdr->t_dflg |= t->t_dflg & 732 (F_NOFORK | F_NOINTERRUPT | F_BACKQ); 733 execute(t->t_dcdr, wanttty, NULL, NULL, do_glob); 734 } 735 break; 736 737 default: 738 break; 739 } 740 /* 741 * Fall through for all breaks from switch 742 * 743 * If there will be no more executions of this command, flush all file 744 * descriptors. Places that turn on the F_REPEAT bit are responsible for 745 * doing donefds after the last re-execution 746 */ 747 if (didfds && !(t->t_dflg & F_REPEAT)) 748 donefds(); 749} 750 751#ifdef VFORK 752static void 753/*ARGSUSED*/ 754vffree(int snum) 755{ 756 USE(snum); 757 758 _exit(1); 759} 760#endif /* VFORK */ 761 762/* 763 * Expand and glob the words after an i/o redirection. 764 * If more than one word is generated, then update the command vector. 765 * 766 * This is done differently in all the shells: 767 * 1. in the bourne shell and ksh globbing is not performed 768 * 2. Bash/csh say ambiguous 769 * 3. zsh does i/o to/from all the files 770 * 4. itcsh concatenates the words. 771 * 772 * I don't know what is best to do. I think that Ambiguous is better 773 * than restructuring the command vector, because the user can get 774 * unexpected results. In any case, the command vector restructuring 775 * code is present and the user can choose it by setting noambiguous 776 */ 777static Char * 778splicepipe(struct command *t, Char *cp) 779{ 780 Char *blk[2]; 781 782 if (adrof(STRnoambiguous)) { 783 Char **pv; 784 int gflag; 785 786 blk[0] = Dfix1(cp); /* expand $ */ 787 blk[1] = NULL; 788 789 gflag = tglob(blk); 790 if (gflag) { 791 pv = globall(blk, gflag); 792 if (pv == NULL) { 793 setname(short2str(blk[0])); 794 xfree(blk[0]); 795 stderror(ERR_NAME | ERR_NOMATCH); 796 } 797 if (pv[1] != NULL) { /* we need to fix the command vector */ 798 Char **av = blkspl(t->t_dcom, &pv[1]); 799 xfree(t->t_dcom); 800 t->t_dcom = av; 801 } 802 xfree(blk[0]); 803 blk[0] = pv[0]; 804 xfree(pv); 805 } 806 } 807 else { 808 Char *buf; 809 810 buf = Dfix1(cp); 811 cleanup_push(buf, xfree); 812 blk[0] = globone(buf, G_ERROR); 813 cleanup_until(buf); 814 } 815 return(blk[0]); 816} 817 818/* 819 * Perform io redirection. 820 * We may or maynot be forked here. 821 */ 822static void 823doio(struct command *t, int *pipein, int *pipeout) 824{ 825 int fd; 826 Char *cp; 827 unsigned long flags = t->t_dflg; 828 829 if (didfds || (flags & F_REPEAT)) 830 return; 831 if ((flags & F_READ) == 0) {/* F_READ already done */ 832 if (t->t_dlef) { 833 char *tmp; 834 835 /* 836 * so < /dev/std{in,out,err} work 837 */ 838 (void) dcopy(SHIN, 0); 839 (void) dcopy(SHOUT, 1); 840 (void) dcopy(SHDIAG, 2); 841 cp = splicepipe(t, t->t_dlef); 842 tmp = strsave(short2str(cp)); 843 xfree(cp); 844 cleanup_push(tmp, xfree); 845 if ((fd = xopen(tmp, O_RDONLY|O_LARGEFILE)) < 0) 846 stderror(ERR_SYSTEM, tmp, strerror(errno)); 847 cleanup_until(tmp); 848 /* allow input files larger than 2Gb */ 849#ifndef WINNT_NATIVE 850 (void) fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_LARGEFILE); 851#endif /*!WINNT_NATIVE*/ 852 (void) dmove(fd, 0); 853 } 854 else if (flags & F_PIPEIN) { 855 xclose(0); 856 TCSH_IGNORE(dup(pipein[0])); 857 xclose(pipein[0]); 858 xclose(pipein[1]); 859 } 860 else if ((flags & F_NOINTERRUPT) && tpgrp == -1) { 861 xclose(0); 862 (void) xopen(_PATH_DEVNULL, O_RDONLY|O_LARGEFILE); 863 } 864 else { 865 xclose(0); 866 TCSH_IGNORE(dup(OLDSTD)); 867#if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 868 /* 869 * PWP: Unlike Bezerkeley 4.3, FIONCLEX for Pyramid is preserved 870 * across dup()s, so we have to UNSET it here or else we get a 871 * command with NO stdin, stdout, or stderr at all (a bad thing 872 * indeed) 873 */ 874 (void) close_on_exec(0, 0); 875#endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 876 } 877 } 878 if (t->t_drit) { 879 char *tmp; 880 881 cp = splicepipe(t, t->t_drit); 882 tmp = strsave(short2str(cp)); 883 xfree(cp); 884 cleanup_push(tmp, xfree); 885 /* 886 * so > /dev/std{out,err} work 887 */ 888 (void) dcopy(SHOUT, 1); 889 (void) dcopy(SHDIAG, 2); 890 if ((flags & F_APPEND) != 0) { 891#ifdef O_APPEND 892 fd = xopen(tmp, O_WRONLY|O_APPEND|O_LARGEFILE); 893#else /* !O_APPEND */ 894 fd = xopen(tmp, O_WRONLY|O_LARGEFILE); 895 (void) lseek(fd, (off_t) 0, L_XTND); 896#endif /* O_APPEND */ 897 } 898 else 899 fd = 0; 900 if ((flags & F_APPEND) == 0 || fd == -1) { 901 if (!(flags & F_OVERWRITE) && adrof(STRnoclobber)) { 902 if (flags & F_APPEND) 903 stderror(ERR_SYSTEM, tmp, strerror(errno)); 904 chkclob(tmp); 905 } 906 if ((fd = xcreat(tmp, 0666)) < 0) 907 stderror(ERR_SYSTEM, tmp, strerror(errno)); 908 /* allow input files larger than 2Gb */ 909#ifndef WINNT_NATIVE 910 (void) fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_LARGEFILE); 911#endif /*!WINNT_NATIVE*/ 912 } 913 cleanup_until(tmp); 914 (void) dmove(fd, 1); 915 is1atty = isatty(1); 916 } 917 else if (flags & F_PIPEOUT) { 918 xclose(1); 919 TCSH_IGNORE(dup(pipeout[1])); 920 is1atty = 0; 921 } 922 else { 923 xclose(1); 924 TCSH_IGNORE(dup(SHOUT)); 925 is1atty = isoutatty; 926# if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 927 (void) close_on_exec(1, 0); 928# endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 929 } 930 931 xclose(2); 932 if (flags & F_STDERR) { 933 TCSH_IGNORE(dup(1)); 934 is2atty = is1atty; 935 } 936 else { 937 TCSH_IGNORE(dup(SHDIAG)); 938 is2atty = isdiagatty; 939# if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS) 940 (void) close_on_exec(2, 0); 941# endif /* CLOSE_ON_EXEC && CLEX_DUPS */ 942 } 943 didfds = 1; 944} 945 946void 947mypipe(int *pv) 948{ 949 950 if (pipe(pv) < 0) 951 goto oops; 952 (void)close_on_exec(pv[0] = dmove(pv[0], -1), 1); 953 (void)close_on_exec(pv[1] = dmove(pv[1], -1), 1); 954 if (pv[0] >= 0 && pv[1] >= 0) 955 return; 956 if (pv[0] >= 0) 957 xclose(pv[0]); 958 if (pv[1] >= 0) 959 xclose(pv[1]); 960oops: 961 stderror(ERR_PIPE); 962} 963 964static void 965chkclob(const char *cp) 966{ 967 struct stat stb; 968 969 if (stat(cp, &stb) < 0) 970 return; 971 if (S_ISCHR(stb.st_mode)) 972 return; 973 stderror(ERR_EXISTS, cp); 974} 975