contrib/tcsh-6/sh.sem.c

   1 /* $Header: /p/tcsh/cvsroot/tcsh/sh.sem.c,v 3.88 2014/09/08 18:52:15 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
  36 RCSID("$tcsh: sh.sem.c,v 3.88 2014/09/08 18:52:15 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
  59 static  void            vffree          (int);
  60 #endif
  61 static  Char            *splicepipe     (struct command *, Char *);
  62 static  void             doio           (struct command *, int *, int *);
  63 static  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*/
  86 void
  87 execute(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 #ifdef BACKPIPE
 350         /*
 351          * Can't have NOFORK for the tail of a pipe - because it is not the
 352          * last command spawned (even if it is at the end of a parenthesised
 353          * list).
 354          */
 355         if (t->t_dflg & F_PIPEIN)
 356             t->t_dflg &= ~(F_NOFORK);
 357 #else
 358         /*
 359          * "command | builtin" may cause major misbehaviour as noted in
 360          * in the BUGS file entry
 361          * Subject: Redirected input to built-in functions misbehaves badly
 362          * forking when the builtin is the end of the pipe corrects the
 363          * problem.
 364          */
 365         if (bifunc && (t->t_dflg & F_PIPEIN))
 366             t->t_dflg &= ~(F_NOFORK);
 367 #endif /* BACKPIPE */
 368         /*
 369          * Prevent forking cd, pushd, popd, chdir cause this will cause the
 370          * shell not to change dir! (XXX: but only for nice?)
 371          */
 372         if (bifunc && (bifunc->bfunct == (bfunc_t)dochngd ||
 373                        bifunc->bfunct == (bfunc_t)dopushd ||
 374                        bifunc->bfunct == (bfunc_t)dopopd))
 375             t->t_dflg &= ~(F_NICE);
 376
 377         if (((t->t_dflg & F_TIME) || ((t->t_dflg & F_NOFORK) == 0 &&
 378              (!bifunc || t->t_dflg &
 379               (F_PIPEOUT | F_AMPERSAND | F_NICE | F_NOHUP | F_HUP)))) ||
 380         /*
 381          * We have to fork for eval too.
 382          */
 383             (bifunc && (t->t_dflg & F_PIPEIN) != 0 &&
 384              bifunc->bfunct == (bfunc_t)doeval)) {
 385 #ifdef VFORK
 386             if (t->t_dtyp == NODE_PAREN ||
 387                 t->t_dflg & (F_REPEAT | F_AMPERSAND) || bifunc)
 388 #endif /* VFORK */
 389             {
 390                 forked++;
 391                 /*
 392                  * We need to block SIGCHLD here, so that if the process does
 393                  * not die before we can set the process group
 394                  */
 395                 if (wanttty >= 0 && !nosigchld) {
 396                     sigemptyset(&set);
 397                     sigaddset(&set, SIGCHLD);
 398                     (void)sigprocmask(SIG_BLOCK, &set, &csigset);
 399
 400                     nosigchld = 1;
 401                 }
 402
 403                 pid = pfork(t, wanttty);
 404                 if (pid == 0 && nosigchld) {
 405                     sigprocmask(SIG_SETMASK, &csigset, NULL);
 406                     nosigchld = 0;
 407                 }
 408                 else if (pid != 0 && (t->t_dflg & F_AMPERSAND))
 409                     backpid = pid;
 410             }
 411
 412 #ifdef VFORK
 413             else {
 414                 int     ochild, osetintr, ohaderr, odidfds;
 415                 int     oSHIN, oSHOUT, oSHDIAG, oOLDSTD, otpgrp;
 416                 int     oisoutatty, oisdiagatty;
 417                 sigset_t oset, ocsigset;
 418 # ifndef CLOSE_ON_EXEC
 419                 int     odidcch;
 420 # endif  /* !CLOSE_ON_EXEC */
 421
 422                 /*
 423                  * Prepare for the vfork by saving everything that the child
 424                  * corrupts before it exec's. Note that in some signal
 425                  * implementations which keep the signal info in user space
 426                  * (e.g. Sun's) it will also be necessary to save and restore
 427                  * the current sigvec's for the signals the child touches
 428                  * before it exec's.
 429                  */
 430
 431                 /*
 432                  * Sooooo true... If this is a Sun, save the sigvec's. (Skip
 433                  * Gilbrech - 11/22/87)
 434                  */
 435 # ifdef SAVESIGVEC
 436                 struct sigaction savesv[NSIGSAVED];
 437                 sigset_t savesm;
 438
 439 # endif /* SAVESIGVEC */
 440                 if (wanttty >= 0 && !nosigchld && !noexec) {
 441                     sigemptyset(&set);
 442                     sigaddset(&set, SIGCHLD);
 443                     (void)sigprocmask(SIG_BLOCK, &set, &csigset);
 444                     nosigchld = 1;
 445                 }
 446                 sigemptyset(&set);
 447                 sigaddset(&set, SIGCHLD);
 448                 sigaddset(&set, SIGINT);
 449                 (void)sigprocmask(SIG_BLOCK, &set, &oset);
 450                 ochild = child;
 451                 osetintr = setintr;
 452                 ohaderr = haderr;
 453                 odidfds = didfds;
 454 # ifndef CLOSE_ON_EXEC
 455                 odidcch = didcch;
 456 # endif /* !CLOSE_ON_EXEC */
 457                 oSHIN = SHIN;
 458                 oSHOUT = SHOUT;
 459                 oSHDIAG = SHDIAG;
 460                 oOLDSTD = OLDSTD;
 461                 otpgrp = tpgrp;
 462                 oisoutatty = isoutatty;
 463                 oisdiagatty = isdiagatty;
 464                 ocsigset = csigset;
 465                 onosigchld = nosigchld;
 466                 Vsav = Vdp = 0;
 467                 Vexpath = 0;
 468                 Vt = 0;
 469 # ifdef SAVESIGVEC
 470                 savesigvec(savesv, savesm);
 471 # endif /* SAVESIGVEC */
 472                 if (use_fork)
 473                     pid = fork();
 474                 else
 475                     pid = vfork();
 476
 477                 if (pid < 0) {
 478 # ifdef SAVESIGVEC
 479                     restoresigvec(savesv, savesm);
 480 # endif /* SAVESIGVEC */
 481                     sigprocmask(SIG_SETMASK, &oset, NULL);
 482                     stderror(ERR_NOPROC);
 483                 }
 484                 forked++;
 485                 if (pid) {      /* parent */
 486 # ifdef SAVESIGVEC
 487                     restoresigvec(savesv, savesm);
 488 # endif /* SAVESIGVEC */
 489                     child = ochild;
 490                     setintr = osetintr;
 491                     haderr = ohaderr;
 492                     didfds = odidfds;
 493                     SHIN = oSHIN;
 494 # ifndef CLOSE_ON_EXEC
 495                     didcch = odidcch;
 496 # endif /* !CLOSE_ON_EXEC */
 497                     SHOUT = oSHOUT;
 498                     SHDIAG = oSHDIAG;
 499                     OLDSTD = oOLDSTD;
 500                     tpgrp = otpgrp;
 501                     isoutatty = oisoutatty;
 502                     isdiagatty = oisdiagatty;
 503                     csigset = ocsigset;
 504                     nosigchld = onosigchld;
 505
 506                     xfree(Vsav);
 507                     Vsav = 0;
 508                     xfree(Vdp);
 509                     Vdp = 0;
 510                     xfree(Vexpath);
 511                     Vexpath = 0;
 512                     blk_cleanup(Vt);
 513                     Vt = 0;
 514                     /* this is from pfork() */
 515                     palloc(pid, t);
 516                     sigprocmask(SIG_SETMASK, &oset, NULL);
 517                 }
 518                 else {          /* child */
 519                     /* this is from pfork() */
 520                     pid_t pgrp;
 521                     int    ignint = 0;
 522                     if (nosigchld) {
 523                         sigprocmask(SIG_SETMASK, &csigset, NULL);
 524                         nosigchld = 0;
 525                     }
 526
 527                     if (setintr)
 528                         ignint = (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT))
 529                                 || (gointr && eq(gointr, STRminus));
 530                     pgrp = pcurrjob ? pcurrjob->p_jobid : getpid();
 531                     child++;
 532                     if (setintr) {
 533                         setintr = 0;
 534 /*
 535  * casts made right for SunOS 4.0 by Douglas C. Schmidt
 536  * <schmidt%sunshine.ics.uci.edu@ROME.ICS.UCI.EDU>
 537  * (thanks! -- PWP)
 538  *
 539  * ignint ifs cleaned by Johan Widen <mcvax!osiris.sics.se!jw@uunet.UU.NET>
 540  * (thanks again)
 541  */
 542                         if (ignint) {
 543                             (void) signal(SIGINT, SIG_IGN);
 544                             (void) signal(SIGQUIT, SIG_IGN);
 545                         }
 546                         else {
 547                             (void) signal(SIGINT, vffree);
 548                             (void) signal(SIGQUIT, SIG_DFL);
 549                         }
 550 # ifdef BSDJOBS
 551                         if (wanttty >= 0) {
 552                             (void) signal(SIGTSTP, SIG_DFL);
 553                             (void) signal(SIGTTIN, SIG_DFL);
 554                             (void) signal(SIGTTOU, SIG_DFL);
 555                         }
 556 # endif /* BSDJOBS */
 557
 558                         sigaction(SIGTERM, &parterm, NULL);
 559                     }
 560                     else if (tpgrp == -1 &&
 561                              (t->t_dflg & F_NOINTERRUPT)) {
 562                         (void) signal(SIGINT, SIG_IGN);
 563                         (void) signal(SIGQUIT, SIG_IGN);
 564                     }
 565
 566                     pgetty(wanttty, pgrp);
 567
 568                     if (t->t_dflg & F_NOHUP)
 569                         (void) signal(SIGHUP, SIG_IGN);
 570                     if (t->t_dflg & F_HUP)
 571                         (void) signal(SIGHUP, SIG_DFL);
 572                     if (t->t_dflg & F_NICE) {
 573                         int nval = SIGN_EXTEND_CHAR(t->t_nice);
 574 # if defined(HAVE_SETPRIORITY) && defined(PRIO_PROCESS)
 575                         if (setpriority(PRIO_PROCESS, 0, nval) == -1 && errno)
 576                                 stderror(ERR_SYSTEM, "setpriority",
 577                                     strerror(errno));
 578 # else /* !HAVE_SETPRIORITY || !PRIO_PROCESS */
 579                         (void) nice(nval);
 580 # endif /* HAVE_SETPRIORITY && PRIO_PROCESS */
 581                     }
 582 # ifdef F_VER
 583                     if (t->t_dflg & F_VER) {
 584                         tsetenv(STRSYSTYPE, t->t_systype ? STRbsd43 : STRsys53);
 585                         dohash(NULL, NULL);
 586                     }
 587 # endif /* F_VER */
 588                 }
 589
 590             }
 591 #endif /* VFORK */
 592         }
 593         if (pid != 0) {
 594             /*
 595              * It would be better if we could wait for the whole job when we
 596              * knew the last process had been started.  Pwait, in fact, does
 597              * wait for the whole job anyway, but this test doesn't really
 598              * express our intentions.
 599              */
 600 #ifdef BACKPIPE
 601             if (didfds == 0 && t->t_dflg & F_PIPEOUT) {
 602                 xclose(pipeout[0]);
 603                 xclose(pipeout[1]);
 604             }
 605             if ((t->t_dflg & F_PIPEIN) != 0)
 606                 break;
 607 #else /* !BACKPIPE */
 608             if (didfds == 0 && t->t_dflg & F_PIPEIN) {
 609                 xclose(pipein[0]);
 610                 xclose(pipein[1]);
 611             }
 612             if ((t->t_dflg & F_PIPEOUT) != 0)
 613                 break;
 614 #endif /* BACKPIPE */
 615
 616             if (nosigchld) {
 617                 sigprocmask(SIG_SETMASK, &csigset, NULL);
 618                 nosigchld = 0;
 619             }
 620             if ((t->t_dflg & F_AMPERSAND) == 0)
 621                 pwait();
 622             break;
 623         }
 624
 625         doio(t, pipein, pipeout);
 626 #ifdef BACKPIPE
 627         if (t->t_dflg & F_PIPEIN) {
 628             xclose(pipein[0]);
 629             xclose(pipein[1]);
 630         }
 631 #else /* !BACKPIPE */
 632         if (t->t_dflg & F_PIPEOUT) {
 633             xclose(pipeout[0]);
 634             xclose(pipeout[1]);
 635         }
 636 #endif /* BACKPIPE */
 637         /*
 638          * Perform a builtin function. If we are not forked, arrange for
 639          * possible stopping
 640          */
 641         if (bifunc) {
 642             if (forked) {
 643                 func(t, bifunc);
 644                 exitstat();
 645             } else {
 646                 jmp_buf_t oldexit;
 647                 int ohaderr = haderr;
 648
 649                 getexit(oldexit);
 650                 if (setexit() == 0)
 651                     func(t, bifunc);
 652                 resexit(oldexit);
 653                 haderr = ohaderr;
 654
 655                 if (adrof(STRprintexitvalue)) {
 656                     int rv = getn(varval(STRstatus));
 657                     if (rv != 0)
 658                         xprintf(CGETS(17, 2, "Exit %d\n"), rv);
 659                 }
 660             }
 661             break;
 662         }
 663         if (t->t_dtyp != NODE_PAREN) {
 664             doexec(t, do_glob);
 665             /* NOTREACHED */
 666         }
 667         /*
 668          * For () commands must put new 0,1,2 in FSH* and recurse
 669          */
 670         if ((OLDSTD = dcopy(0, FOLDSTD)) >= 0)
 671             (void)close_on_exec(OLDSTD, 1);
 672         if ((SHOUT = dcopy(1, FSHOUT)) >= 0) {
 673             (void)close_on_exec(SHOUT, 1);
 674             isoutatty = isatty(SHOUT);
 675         }
 676         if ((SHDIAG = dcopy(2, FSHDIAG)) >= 0) {
 677             (void)close_on_exec(SHDIAG, 1);
 678             isdiagatty = isatty(SHDIAG);
 679         }
 680         xclose(SHIN);
 681         SHIN = -1;
 682 #ifndef CLOSE_ON_EXEC
 683         didcch = 0;
 684 #else
 685         (void) close_on_exec(FSHOUT, 1);
 686         (void) close_on_exec(FSHDIAG, 1);
 687         (void) close_on_exec(FOLDSTD, 1);
 688 #endif /* !CLOSE_ON_EXEC */
 689         didfds = 0;
 690         wanttty = -1;
 691         t->t_dspr->t_dflg |= t->t_dflg & (F_NOINTERRUPT | F_BACKQ);
 692         execute(t->t_dspr, wanttty, NULL, NULL, do_glob);
 693         exitstat();
 694
 695     case NODE_PIPE:
 696 #ifdef BACKPIPE
 697         t->t_dcdr->t_dflg |= F_PIPEIN | (t->t_dflg &
 698             (F_PIPEOUT | F_AMPERSAND | F_NOFORK | F_NOINTERRUPT | F_BACKQ));
 699         execute(t->t_dcdr, wanttty, pv, pipeout, do_glob);
 700         t->t_dcar->t_dflg |= F_PIPEOUT | (t->t_dflg &
 701             (F_PIPEIN | F_AMPERSAND | F_STDERR | F_NOINTERRUPT | F_BACKQ));
 702         execute(t->t_dcar, wanttty, pipein, pv, do_glob);
 703 #else /* !BACKPIPE */
 704         t->t_dcar->t_dflg |= F_PIPEOUT | (t->t_dflg &
 705             (F_PIPEIN | F_AMPERSAND | F_STDERR | F_NOINTERRUPT | F_BACKQ));
 706         execute(t->t_dcar, wanttty, pipein, pv, do_glob);
 707         t->t_dcdr->t_dflg |= F_PIPEIN | (t->t_dflg &
 708             (F_PIPEOUT | F_AMPERSAND | F_NOFORK | F_NOINTERRUPT | F_BACKQ));
 709         execute(t->t_dcdr, wanttty, pv, pipeout, do_glob);
 710 #endif /* BACKPIPE */
 711         break;
 712
 713     case NODE_LIST:
 714         if (t->t_dcar) {
 715             t->t_dcar->t_dflg |= t->t_dflg & (F_NOINTERRUPT | F_BACKQ);
 716             execute(t->t_dcar, wanttty, NULL, NULL, do_glob);
 717             /*
 718              * In strange case of A&B make a new job after A
 719              */
 720             if (t->t_dcar->t_dflg & F_AMPERSAND && t->t_dcdr &&
 721                 (t->t_dcdr->t_dflg & F_AMPERSAND) == 0)
 722                 pendjob();
 723         }
 724         if (t->t_dcdr) {
 725             t->t_dcdr->t_dflg |= t->t_dflg &
 726                 (F_NOFORK | F_NOINTERRUPT | F_BACKQ);
 727             execute(t->t_dcdr, wanttty, NULL, NULL, do_glob);
 728         }
 729         break;
 730
 731     case NODE_OR:
 732     case NODE_AND:
 733         if (t->t_dcar) {
 734             t->t_dcar->t_dflg |= t->t_dflg & (F_NOINTERRUPT | F_BACKQ);
 735             execute(t->t_dcar, wanttty, NULL, NULL, do_glob);
 736             if ((getn(varval(STRstatus)) == 0) !=
 737                 (t->t_dtyp == NODE_AND)) {
 738                 return;
 739             }
 740         }
 741         if (t->t_dcdr) {
 742             t->t_dcdr->t_dflg |= t->t_dflg &
 743                 (F_NOFORK | F_NOINTERRUPT | F_BACKQ);
 744             execute(t->t_dcdr, wanttty, NULL, NULL, do_glob);
 745         }
 746         break;
 747
 748     default:
 749         break;
 750     }
 751     /*
 752      * Fall through for all breaks from switch
 753      *
 754      * If there will be no more executions of this command, flush all file
 755      * descriptors. Places that turn on the F_REPEAT bit are responsible for
 756      * doing donefds after the last re-execution
 757      */
 758     if (didfds && !(t->t_dflg & F_REPEAT))
 759         donefds();
 760 }
 761
 762 #ifdef VFORK
 763 static void
 764 /*ARGSUSED*/
 765 vffree(int snum)
 766 {
 767     USE(snum);
 768
 769     _exit(1);
 770 }
 771 #endif /* VFORK */
 772
 773 /*
 774  * Expand and glob the words after an i/o redirection.
 775  * If more than one word is generated, then update the command vector.
 776  *
 777  * This is done differently in all the shells:
 778  * 1. in the bourne shell and ksh globbing is not performed
 779  * 2. Bash/csh say ambiguous
 780  * 3. zsh does i/o to/from all the files
 781  * 4. itcsh concatenates the words.
 782  *
 783  * I don't know what is best to do. I think that Ambiguous is better
 784  * than restructuring the command vector, because the user can get
 785  * unexpected results. In any case, the command vector restructuring
 786  * code is present and the user can choose it by setting noambiguous
 787  */
 788 static Char *
 789 splicepipe(struct command *t, Char *cp)
 790 {
 791     Char *blk[2];
 792
 793     if (adrof(STRnoambiguous)) {
 794         Char **pv;
 795         int gflag;
 796
 797         blk[0] = Dfix1(cp); /* expand $ */
 798         blk[1] = NULL;
 799
 800         gflag = tglob(blk);
 801         if (gflag) {
 802             pv = globall(blk, gflag);
 803             if (pv == NULL) {
 804                 setname(short2str(blk[0]));
 805                 xfree(blk[0]);
 806                 stderror(ERR_NAME | ERR_NOMATCH);
 807             }
 808             if (pv[1] != NULL) { /* we need to fix the command vector */
 809                 Char **av = blkspl(t->t_dcom, &pv[1]);
 810                 xfree(t->t_dcom);
 811                 t->t_dcom = av;
 812             }
 813             xfree(blk[0]);
 814             blk[0] = pv[0];
 815             xfree(pv);
 816         }
 817     }
 818     else {
 819         Char *buf;
 820
 821         buf = Dfix1(cp);
 822         cleanup_push(buf, xfree);
 823         blk[0] = globone(buf, G_ERROR);
 824         cleanup_until(buf);
 825     }
 826     return(blk[0]);
 827 }
 828
 829 /*
 830  * Perform io redirection.
 831  * We may or maynot be forked here.
 832  */
 833 static void
 834 doio(struct command *t, int *pipein, int *pipeout)
 835 {
 836     int fd;
 837     Char *cp;
 838     unsigned long flags = t->t_dflg;
 839
 840     if (didfds || (flags & F_REPEAT))
 841         return;
 842     if ((flags & F_READ) == 0) {/* F_READ already done */
 843         if (t->t_dlef) {
 844             char *tmp;
 845
 846             /*
 847              * so < /dev/std{in,out,err} work
 848              */
 849             (void) dcopy(SHIN, 0);
 850             (void) dcopy(SHOUT, 1);
 851             (void) dcopy(SHDIAG, 2);
 852             cp = splicepipe(t, t->t_dlef);
 853             tmp = strsave(short2str(cp));
 854             xfree(cp);
 855             cleanup_push(tmp, xfree);
 856             if ((fd = xopen(tmp, O_RDONLY|O_LARGEFILE)) < 0)
 857                 stderror(ERR_SYSTEM, tmp, strerror(errno));
 858             cleanup_until(tmp);
 859             /* allow input files larger than 2Gb  */
 860 #ifndef WINNT_NATIVE
 861             (void) fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_LARGEFILE);
 862 #endif /*!WINNT_NATIVE*/
 863             (void) dmove(fd, 0);
 864         }
 865         else if (flags & F_PIPEIN) {
 866             xclose(0);
 867             TCSH_IGNORE(dup(pipein[0]));
 868             xclose(pipein[0]);
 869             xclose(pipein[1]);
 870         }
 871         else if ((flags & F_NOINTERRUPT) && tpgrp == -1) {
 872             xclose(0);
 873             (void) xopen(_PATH_DEVNULL, O_RDONLY|O_LARGEFILE);
 874         }
 875         else {
 876             xclose(0);
 877             TCSH_IGNORE(dup(OLDSTD));
 878 #if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS)
 879             /*
 880              * PWP: Unlike Bezerkeley 4.3, FIONCLEX for Pyramid is preserved
 881              * across dup()s, so we have to UNSET it here or else we get a
 882              * command with NO stdin, stdout, or stderr at all (a bad thing
 883              * indeed)
 884              */
 885             (void) close_on_exec(0, 0);
 886 #endif /* CLOSE_ON_EXEC && CLEX_DUPS */
 887         }
 888     }
 889     if (t->t_drit) {
 890         char *tmp;
 891
 892         cp = splicepipe(t, t->t_drit);
 893         tmp = strsave(short2str(cp));
 894         xfree(cp);
 895         cleanup_push(tmp, xfree);
 896         /*
 897          * so > /dev/std{out,err} work
 898          */
 899         (void) dcopy(SHOUT, 1);
 900         (void) dcopy(SHDIAG, 2);
 901         if ((flags & F_APPEND) != 0) {
 902 #ifdef O_APPEND
 903             fd = xopen(tmp, O_WRONLY|O_APPEND|O_LARGEFILE);
 904 #else /* !O_APPEND */
 905             fd = xopen(tmp, O_WRONLY|O_LARGEFILE);
 906             (void) lseek(fd, (off_t) 0, L_XTND);
 907 #endif /* O_APPEND */
 908         }
 909         else
 910             fd = 0;
 911         if ((flags & F_APPEND) == 0 || fd == -1) {
 912             if (!(flags & F_OVERWRITE) && adrof(STRnoclobber)) {
 913                 if (flags & F_APPEND)
 914                     stderror(ERR_SYSTEM, tmp, strerror(errno));
 915                 chkclob(tmp);
 916             }
 917             if ((fd = xcreat(tmp, 0666)) < 0)
 918                 stderror(ERR_SYSTEM, tmp, strerror(errno));
 919             /* allow input files larger than 2Gb  */
 920 #ifndef WINNT_NATIVE
 921             (void) fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_LARGEFILE);
 922 #endif /*!WINNT_NATIVE*/
 923         }
 924         cleanup_until(tmp);
 925         (void) dmove(fd, 1);
 926         is1atty = isatty(1);
 927     }
 928     else if (flags & F_PIPEOUT) {
 929         xclose(1);
 930         TCSH_IGNORE(dup(pipeout[1]));
 931         is1atty = 0;
 932     }
 933     else {
 934         xclose(1);
 935         TCSH_IGNORE(dup(SHOUT));
 936         is1atty = isoutatty;
 937 # if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS)
 938         (void) close_on_exec(1, 0);
 939 # endif /* CLOSE_ON_EXEC && CLEX_DUPS */
 940     }
 941
 942     xclose(2);
 943     if (flags & F_STDERR) {
 944         TCSH_IGNORE(dup(1));
 945         is2atty = is1atty;
 946     }
 947     else {
 948         TCSH_IGNORE(dup(SHDIAG));
 949         is2atty = isdiagatty;
 950 # if defined(CLOSE_ON_EXEC) && defined(CLEX_DUPS)
 951         (void) close_on_exec(2, 0);
 952 # endif /* CLOSE_ON_EXEC && CLEX_DUPS */
 953     }
 954     didfds = 1;
 955 }
 956
 957 void
 958 mypipe(int *pv)
 959 {
 960
 961     if (pipe(pv) < 0)
 962         goto oops;
 963     (void)close_on_exec(pv[0] = dmove(pv[0], -1), 1);
 964     (void)close_on_exec(pv[1] = dmove(pv[1], -1), 1);
 965     if (pv[0] >= 0 && pv[1] >= 0)
 966         return;
 967     if (pv[0] >= 0)
 968         xclose(pv[0]);
 969     if (pv[1] >= 0)
 970         xclose(pv[1]);
 971 oops:
 972     stderror(ERR_PIPE);
 973 }
 974
 975 static void
 976 chkclob(const char *cp)
 977 {
 978     struct stat stb;
 979
 980     if (stat(cp, &stb) < 0)
 981         return;
 982     if (S_ISCHR(stb.st_mode))
 983         return;
 984     stderror(ERR_EXISTS, cp);
 985 }