eval.c revision 100437
11556Srgrimes/*- 21556Srgrimes * Copyright (c) 1993 31556Srgrimes * The Regents of the University of California. All rights reserved. 41556Srgrimes * 51556Srgrimes * This code is derived from software contributed to Berkeley by 61556Srgrimes * Kenneth Almquist. 71556Srgrimes * 81556Srgrimes * Redistribution and use in source and binary forms, with or without 91556Srgrimes * modification, are permitted provided that the following conditions 101556Srgrimes * are met: 111556Srgrimes * 1. Redistributions of source code must retain the above copyright 121556Srgrimes * notice, this list of conditions and the following disclaimer. 131556Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141556Srgrimes * notice, this list of conditions and the following disclaimer in the 151556Srgrimes * documentation and/or other materials provided with the distribution. 161556Srgrimes * 3. All advertising materials mentioning features or use of this software 171556Srgrimes * must display the following acknowledgement: 181556Srgrimes * This product includes software developed by the University of 191556Srgrimes * California, Berkeley and its contributors. 201556Srgrimes * 4. Neither the name of the University nor the names of its contributors 211556Srgrimes * may be used to endorse or promote products derived from this software 221556Srgrimes * without specific prior written permission. 231556Srgrimes * 241556Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 251556Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 261556Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 271556Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 281556Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 291556Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 301556Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 311556Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 321556Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 331556Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 341556Srgrimes * SUCH DAMAGE. 351556Srgrimes */ 361556Srgrimes 371556Srgrimes#ifndef lint 3836150Scharnier#if 0 3936150Scharnierstatic char sccsid[] = "@(#)eval.c 8.9 (Berkeley) 6/8/95"; 4036150Scharnier#endif 411556Srgrimes#endif /* not lint */ 4299110Sobrien#include <sys/cdefs.h> 4399110Sobrien__FBSDID("$FreeBSD: head/bin/sh/eval.c 100437 2002-07-21 06:49:14Z tjr $"); 441556Srgrimes 45100437Stjr#include <paths.h> 4617987Speter#include <signal.h> 4717987Speter#include <unistd.h> 4845266Scracauer#include <sys/wait.h> /* For WIFSIGNALED(status) */ 4953891Scracauer#include <errno.h> 5017987Speter 511556Srgrimes/* 521556Srgrimes * Evaluate a command. 531556Srgrimes */ 541556Srgrimes 551556Srgrimes#include "shell.h" 561556Srgrimes#include "nodes.h" 571556Srgrimes#include "syntax.h" 581556Srgrimes#include "expand.h" 591556Srgrimes#include "parser.h" 601556Srgrimes#include "jobs.h" 611556Srgrimes#include "eval.h" 621556Srgrimes#include "builtins.h" 631556Srgrimes#include "options.h" 641556Srgrimes#include "exec.h" 651556Srgrimes#include "redir.h" 661556Srgrimes#include "input.h" 671556Srgrimes#include "output.h" 681556Srgrimes#include "trap.h" 691556Srgrimes#include "var.h" 701556Srgrimes#include "memalloc.h" 711556Srgrimes#include "error.h" 7217987Speter#include "show.h" 731556Srgrimes#include "mystring.h" 7417987Speter#ifndef NO_HISTORY 751556Srgrimes#include "myhistedit.h" 7617987Speter#endif 771556Srgrimes 781556Srgrimes 791556Srgrimes/* flags in argument to evaltree */ 801556Srgrimes#define EV_EXIT 01 /* exit after evaluating tree */ 811556Srgrimes#define EV_TESTED 02 /* exit status is checked; ignore -e flag */ 821556Srgrimes#define EV_BACKCMD 04 /* command executing within back quotes */ 831556Srgrimes 841556SrgrimesMKINIT int evalskip; /* set if we are skipping commands */ 851556SrgrimesSTATIC int skipcount; /* number of levels to skip */ 861556SrgrimesMKINIT int loopnest; /* current loop nesting level */ 871556Srgrimesint funcnest; /* depth of function calls */ 881556Srgrimes 891556Srgrimes 901556Srgrimeschar *commandname; 911556Srgrimesstruct strlist *cmdenviron; 921556Srgrimesint exitstatus; /* exit status of last command */ 9317987Speterint oexitstatus; /* saved exit status */ 941556Srgrimes 951556Srgrimes 9690111SimpSTATIC void evalloop(union node *); 9790111SimpSTATIC void evalfor(union node *); 9890111SimpSTATIC void evalcase(union node *, int); 9990111SimpSTATIC void evalsubshell(union node *, int); 10090111SimpSTATIC void expredir(union node *); 10190111SimpSTATIC void evalpipe(union node *); 10290111SimpSTATIC void evalcommand(union node *, int, struct backcmd *); 10390111SimpSTATIC void prehash(union node *); 1041556Srgrimes 1051556Srgrimes 1061556Srgrimes/* 1071556Srgrimes * Called to reset things after an exception. 1081556Srgrimes */ 1091556Srgrimes 1101556Srgrimes#ifdef mkinit 1111556SrgrimesINCLUDE "eval.h" 1121556Srgrimes 1131556SrgrimesRESET { 1141556Srgrimes evalskip = 0; 1151556Srgrimes loopnest = 0; 1161556Srgrimes funcnest = 0; 1171556Srgrimes} 1181556Srgrimes 1191556SrgrimesSHELLPROC { 1201556Srgrimes exitstatus = 0; 1211556Srgrimes} 1221556Srgrimes#endif 1231556Srgrimes 1241556Srgrimes 1251556Srgrimes 1261556Srgrimes/* 12746684Skris * The eval command. 1281556Srgrimes */ 1291556Srgrimes 13017987Speterint 13190111Simpevalcmd(int argc, char **argv) 1321556Srgrimes{ 1331556Srgrimes char *p; 1341556Srgrimes char *concat; 1351556Srgrimes char **ap; 1361556Srgrimes 1371556Srgrimes if (argc > 1) { 1381556Srgrimes p = argv[1]; 1391556Srgrimes if (argc > 2) { 1401556Srgrimes STARTSTACKSTR(concat); 1411556Srgrimes ap = argv + 2; 1421556Srgrimes for (;;) { 1431556Srgrimes while (*p) 1441556Srgrimes STPUTC(*p++, concat); 1451556Srgrimes if ((p = *ap++) == NULL) 1461556Srgrimes break; 1471556Srgrimes STPUTC(' ', concat); 1481556Srgrimes } 1491556Srgrimes STPUTC('\0', concat); 1501556Srgrimes p = grabstackstr(concat); 1511556Srgrimes } 1521556Srgrimes evalstring(p); 1531556Srgrimes } 1541556Srgrimes return exitstatus; 1551556Srgrimes} 1561556Srgrimes 1571556Srgrimes 1581556Srgrimes/* 1591556Srgrimes * Execute a command or commands contained in a string. 1601556Srgrimes */ 1611556Srgrimes 1621556Srgrimesvoid 16390111Simpevalstring(char *s) 16490111Simp{ 1651556Srgrimes union node *n; 1661556Srgrimes struct stackmark smark; 1671556Srgrimes 1681556Srgrimes setstackmark(&smark); 1691556Srgrimes setinputstring(s, 1); 1701556Srgrimes while ((n = parsecmd(0)) != NEOF) { 1711556Srgrimes evaltree(n, 0); 1721556Srgrimes popstackmark(&smark); 1731556Srgrimes } 1741556Srgrimes popfile(); 1751556Srgrimes popstackmark(&smark); 1761556Srgrimes} 1771556Srgrimes 1781556Srgrimes 1791556Srgrimes 1801556Srgrimes/* 1811556Srgrimes * Evaluate a parse tree. The value is left in the global variable 1821556Srgrimes * exitstatus. 1831556Srgrimes */ 1841556Srgrimes 1851556Srgrimesvoid 18690111Simpevaltree(union node *n, int flags) 18717987Speter{ 1881556Srgrimes if (n == NULL) { 1891556Srgrimes TRACE(("evaltree(NULL) called\n")); 1901556Srgrimes exitstatus = 0; 1911556Srgrimes goto out; 1921556Srgrimes } 19317987Speter#ifndef NO_HISTORY 1941556Srgrimes displayhist = 1; /* show history substitutions done with fc */ 19517987Speter#endif 19617987Speter TRACE(("evaltree(0x%lx: %d) called\n", (long)n, n->type)); 1971556Srgrimes switch (n->type) { 1981556Srgrimes case NSEMI: 1991556Srgrimes evaltree(n->nbinary.ch1, 0); 2001556Srgrimes if (evalskip) 2011556Srgrimes goto out; 2021556Srgrimes evaltree(n->nbinary.ch2, flags); 2031556Srgrimes break; 2041556Srgrimes case NAND: 2051556Srgrimes evaltree(n->nbinary.ch1, EV_TESTED); 20618754Ssteve if (evalskip || exitstatus != 0) { 20718754Ssteve flags |= EV_TESTED; 2081556Srgrimes goto out; 20918754Ssteve } 2101556Srgrimes evaltree(n->nbinary.ch2, flags); 2111556Srgrimes break; 2121556Srgrimes case NOR: 2131556Srgrimes evaltree(n->nbinary.ch1, EV_TESTED); 2141556Srgrimes if (evalskip || exitstatus == 0) 2151556Srgrimes goto out; 2161556Srgrimes evaltree(n->nbinary.ch2, flags); 2171556Srgrimes break; 2181556Srgrimes case NREDIR: 2191556Srgrimes expredir(n->nredir.redirect); 2201556Srgrimes redirect(n->nredir.redirect, REDIR_PUSH); 2211556Srgrimes evaltree(n->nredir.n, flags); 2221556Srgrimes popredir(); 2231556Srgrimes break; 2241556Srgrimes case NSUBSHELL: 2251556Srgrimes evalsubshell(n, flags); 2261556Srgrimes break; 2271556Srgrimes case NBACKGND: 2281556Srgrimes evalsubshell(n, flags); 2291556Srgrimes break; 2301556Srgrimes case NIF: { 2311556Srgrimes evaltree(n->nif.test, EV_TESTED); 2321556Srgrimes if (evalskip) 2331556Srgrimes goto out; 23420425Ssteve if (exitstatus == 0) 2351556Srgrimes evaltree(n->nif.ifpart, flags); 23617987Speter else if (n->nif.elsepart) 2371556Srgrimes evaltree(n->nif.elsepart, flags); 23820425Ssteve else 23920425Ssteve exitstatus = 0; 2401556Srgrimes break; 2411556Srgrimes } 2421556Srgrimes case NWHILE: 2431556Srgrimes case NUNTIL: 2441556Srgrimes evalloop(n); 2451556Srgrimes break; 2461556Srgrimes case NFOR: 2471556Srgrimes evalfor(n); 24877557Sgad /* 24977557Sgad * The 'for' command does not set exitstatus, so the value 25077557Sgad * now in exitstatus is from the last command executed in 25177557Sgad * the 'for' loop. That exit value had been tested (wrt 25277557Sgad * 'sh -e' checking) while processing that command, and 25377557Sgad * it should not be re-tested here. 25477557Sgad */ 25577557Sgad flags |= EV_TESTED; 2561556Srgrimes break; 2571556Srgrimes case NCASE: 2581556Srgrimes evalcase(n, flags); 25977557Sgad /* 26077557Sgad * The 'case' command does not set exitstatus, so the value 26177557Sgad * now in exitstatus is from the last command executed in 26277557Sgad * the 'case' block. That exit value had been tested (wrt 26377557Sgad * 'sh -e' checking) while processing that command, and 26477557Sgad * it should not be re-tested here. 26577557Sgad */ 26677557Sgad flags |= EV_TESTED; 2671556Srgrimes break; 2681556Srgrimes case NDEFUN: 2691556Srgrimes defun(n->narg.text, n->narg.next); 2701556Srgrimes exitstatus = 0; 2711556Srgrimes break; 2721556Srgrimes case NNOT: 2731556Srgrimes evaltree(n->nnot.com, EV_TESTED); 2741556Srgrimes exitstatus = !exitstatus; 2751556Srgrimes break; 2761556Srgrimes 2771556Srgrimes case NPIPE: 2781556Srgrimes evalpipe(n); 2791556Srgrimes break; 2801556Srgrimes case NCMD: 2811556Srgrimes evalcommand(n, flags, (struct backcmd *)NULL); 2821556Srgrimes break; 2831556Srgrimes default: 2841556Srgrimes out1fmt("Node type = %d\n", n->type); 2851556Srgrimes flushout(&output); 2861556Srgrimes break; 2871556Srgrimes } 2881556Srgrimesout: 2891556Srgrimes if (pendingsigs) 2901556Srgrimes dotrap(); 29152526Scracauer /* 29252526Scracauer * XXX - Like "!(n->type == NSEMI)", more types will probably 29352526Scracauer * need to be excluded from this test. It's probably better 29452526Scracauer * to set or unset EV_TESTED in the loop above than to bloat 29552526Scracauer * the conditional here. 29652526Scracauer */ 29752526Scracauer if ((flags & EV_EXIT) || (eflag && exitstatus 29852526Scracauer && !(flags & EV_TESTED) && !(n->type == NSEMI))) 2991556Srgrimes exitshell(exitstatus); 3001556Srgrimes} 3011556Srgrimes 3021556Srgrimes 3031556SrgrimesSTATIC void 30490111Simpevalloop(union node *n) 30517987Speter{ 3061556Srgrimes int status; 3071556Srgrimes 3081556Srgrimes loopnest++; 3091556Srgrimes status = 0; 3101556Srgrimes for (;;) { 3111556Srgrimes evaltree(n->nbinary.ch1, EV_TESTED); 3121556Srgrimes if (evalskip) { 3131556Srgrimesskipping: if (evalskip == SKIPCONT && --skipcount <= 0) { 3141556Srgrimes evalskip = 0; 3151556Srgrimes continue; 3161556Srgrimes } 3171556Srgrimes if (evalskip == SKIPBREAK && --skipcount <= 0) 3181556Srgrimes evalskip = 0; 3191556Srgrimes break; 3201556Srgrimes } 3211556Srgrimes if (n->type == NWHILE) { 3221556Srgrimes if (exitstatus != 0) 3231556Srgrimes break; 3241556Srgrimes } else { 3251556Srgrimes if (exitstatus == 0) 3261556Srgrimes break; 3271556Srgrimes } 3281556Srgrimes evaltree(n->nbinary.ch2, 0); 3291556Srgrimes status = exitstatus; 3301556Srgrimes if (evalskip) 3311556Srgrimes goto skipping; 3321556Srgrimes } 3331556Srgrimes loopnest--; 3341556Srgrimes exitstatus = status; 3351556Srgrimes} 3361556Srgrimes 3371556Srgrimes 3381556Srgrimes 3391556SrgrimesSTATIC void 34090111Simpevalfor(union node *n) 34117987Speter{ 3421556Srgrimes struct arglist arglist; 3431556Srgrimes union node *argp; 3441556Srgrimes struct strlist *sp; 3451556Srgrimes struct stackmark smark; 3461556Srgrimes 3471556Srgrimes setstackmark(&smark); 3481556Srgrimes arglist.lastp = &arglist.list; 3491556Srgrimes for (argp = n->nfor.args ; argp ; argp = argp->narg.next) { 35017987Speter oexitstatus = exitstatus; 3511556Srgrimes expandarg(argp, &arglist, EXP_FULL | EXP_TILDE); 3521556Srgrimes if (evalskip) 3531556Srgrimes goto out; 3541556Srgrimes } 3551556Srgrimes *arglist.lastp = NULL; 3561556Srgrimes 3571556Srgrimes exitstatus = 0; 3581556Srgrimes loopnest++; 3591556Srgrimes for (sp = arglist.list ; sp ; sp = sp->next) { 3601556Srgrimes setvar(n->nfor.var, sp->text, 0); 3611556Srgrimes evaltree(n->nfor.body, 0); 3621556Srgrimes if (evalskip) { 3631556Srgrimes if (evalskip == SKIPCONT && --skipcount <= 0) { 3641556Srgrimes evalskip = 0; 3651556Srgrimes continue; 3661556Srgrimes } 3671556Srgrimes if (evalskip == SKIPBREAK && --skipcount <= 0) 3681556Srgrimes evalskip = 0; 3691556Srgrimes break; 3701556Srgrimes } 3711556Srgrimes } 3721556Srgrimes loopnest--; 3731556Srgrimesout: 3741556Srgrimes popstackmark(&smark); 3751556Srgrimes} 3761556Srgrimes 3771556Srgrimes 3781556Srgrimes 3791556SrgrimesSTATIC void 38090111Simpevalcase(union node *n, int flags) 38117987Speter{ 3821556Srgrimes union node *cp; 3831556Srgrimes union node *patp; 3841556Srgrimes struct arglist arglist; 3851556Srgrimes struct stackmark smark; 3861556Srgrimes 3871556Srgrimes setstackmark(&smark); 3881556Srgrimes arglist.lastp = &arglist.list; 38917987Speter oexitstatus = exitstatus; 3901556Srgrimes expandarg(n->ncase.expr, &arglist, EXP_TILDE); 3911556Srgrimes for (cp = n->ncase.cases ; cp && evalskip == 0 ; cp = cp->nclist.next) { 3921556Srgrimes for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) { 3931556Srgrimes if (casematch(patp, arglist.list->text)) { 3941556Srgrimes if (evalskip == 0) { 3951556Srgrimes evaltree(cp->nclist.body, flags); 3961556Srgrimes } 3971556Srgrimes goto out; 3981556Srgrimes } 3991556Srgrimes } 4001556Srgrimes } 4011556Srgrimesout: 4021556Srgrimes popstackmark(&smark); 4031556Srgrimes} 4041556Srgrimes 4051556Srgrimes 4061556Srgrimes 4071556Srgrimes/* 4081556Srgrimes * Kick off a subshell to evaluate a tree. 4091556Srgrimes */ 4101556Srgrimes 4111556SrgrimesSTATIC void 41290111Simpevalsubshell(union node *n, int flags) 41317987Speter{ 4141556Srgrimes struct job *jp; 4151556Srgrimes int backgnd = (n->type == NBACKGND); 4161556Srgrimes 4171556Srgrimes expredir(n->nredir.redirect); 4181556Srgrimes jp = makejob(n, 1); 4191556Srgrimes if (forkshell(jp, n, backgnd) == 0) { 4201556Srgrimes if (backgnd) 4211556Srgrimes flags &=~ EV_TESTED; 4221556Srgrimes redirect(n->nredir.redirect, 0); 4231556Srgrimes evaltree(n->nredir.n, flags | EV_EXIT); /* never returns */ 4241556Srgrimes } 4251556Srgrimes if (! backgnd) { 4261556Srgrimes INTOFF; 42745916Scracauer exitstatus = waitforjob(jp, (int *)NULL); 4281556Srgrimes INTON; 4291556Srgrimes } 4301556Srgrimes} 4311556Srgrimes 4321556Srgrimes 4331556Srgrimes 4341556Srgrimes/* 4351556Srgrimes * Compute the names of the files in a redirection list. 4361556Srgrimes */ 4371556Srgrimes 4381556SrgrimesSTATIC void 43990111Simpexpredir(union node *n) 44017987Speter{ 44125222Ssteve union node *redir; 4421556Srgrimes 4431556Srgrimes for (redir = n ; redir ; redir = redir->nfile.next) { 44417987Speter struct arglist fn; 44517987Speter fn.lastp = &fn.list; 44617987Speter oexitstatus = exitstatus; 44717987Speter switch (redir->type) { 44817987Speter case NFROM: 44917987Speter case NTO: 45066612Sbrian case NFROMTO: 45117987Speter case NAPPEND: 45296922Stjr case NCLOBBER: 4531556Srgrimes expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR); 4541556Srgrimes redir->nfile.expfname = fn.list->text; 45517987Speter break; 45617987Speter case NFROMFD: 45717987Speter case NTOFD: 45817987Speter if (redir->ndup.vname) { 45917987Speter expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE); 46017987Speter fixredir(redir, fn.list->text, 1); 46117987Speter } 46217987Speter break; 4631556Srgrimes } 4641556Srgrimes } 4651556Srgrimes} 4661556Srgrimes 4671556Srgrimes 4681556Srgrimes 4691556Srgrimes/* 4701556Srgrimes * Evaluate a pipeline. All the processes in the pipeline are children 4711556Srgrimes * of the process creating the pipeline. (This differs from some versions 4721556Srgrimes * of the shell, which make the last process in a pipeline the parent 4731556Srgrimes * of all the rest.) 4741556Srgrimes */ 4751556Srgrimes 4761556SrgrimesSTATIC void 47790111Simpevalpipe(union node *n) 47817987Speter{ 4791556Srgrimes struct job *jp; 4801556Srgrimes struct nodelist *lp; 4811556Srgrimes int pipelen; 4821556Srgrimes int prevfd; 4831556Srgrimes int pip[2]; 4841556Srgrimes 48517987Speter TRACE(("evalpipe(0x%lx) called\n", (long)n)); 4861556Srgrimes pipelen = 0; 4871556Srgrimes for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) 4881556Srgrimes pipelen++; 4891556Srgrimes INTOFF; 4901556Srgrimes jp = makejob(n, pipelen); 4911556Srgrimes prevfd = -1; 4921556Srgrimes for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 4931556Srgrimes prehash(lp->n); 4941556Srgrimes pip[1] = -1; 4951556Srgrimes if (lp->next) { 4961556Srgrimes if (pipe(pip) < 0) { 4971556Srgrimes close(prevfd); 49853891Scracauer error("Pipe call failed: %s", strerror(errno)); 4991556Srgrimes } 5001556Srgrimes } 5011556Srgrimes if (forkshell(jp, lp->n, n->npipe.backgnd) == 0) { 5021556Srgrimes INTON; 5031556Srgrimes if (prevfd > 0) { 5041556Srgrimes close(0); 5051556Srgrimes copyfd(prevfd, 0); 5061556Srgrimes close(prevfd); 5071556Srgrimes } 5081556Srgrimes if (pip[1] >= 0) { 50953282Scracauer if (!(prevfd >= 0 && pip[0] == 0)) 51052900Scracauer close(pip[0]); 5111556Srgrimes if (pip[1] != 1) { 5121556Srgrimes close(1); 5131556Srgrimes copyfd(pip[1], 1); 5141556Srgrimes close(pip[1]); 5151556Srgrimes } 5161556Srgrimes } 5171556Srgrimes evaltree(lp->n, EV_EXIT); 5181556Srgrimes } 5191556Srgrimes if (prevfd >= 0) 5201556Srgrimes close(prevfd); 5211556Srgrimes prevfd = pip[0]; 5221556Srgrimes close(pip[1]); 5231556Srgrimes } 5241556Srgrimes INTON; 5251556Srgrimes if (n->npipe.backgnd == 0) { 5261556Srgrimes INTOFF; 52745916Scracauer exitstatus = waitforjob(jp, (int *)NULL); 5281556Srgrimes TRACE(("evalpipe: job done exit status %d\n", exitstatus)); 5291556Srgrimes INTON; 5301556Srgrimes } 5311556Srgrimes} 5321556Srgrimes 5331556Srgrimes 5341556Srgrimes 5351556Srgrimes/* 5361556Srgrimes * Execute a command inside back quotes. If it's a builtin command, we 5371556Srgrimes * want to save its output in a block obtained from malloc. Otherwise 5381556Srgrimes * we fork off a subprocess and get the output of the command via a pipe. 5391556Srgrimes * Should be called with interrupts off. 5401556Srgrimes */ 5411556Srgrimes 5421556Srgrimesvoid 54390111Simpevalbackcmd(union node *n, struct backcmd *result) 54417987Speter{ 5451556Srgrimes int pip[2]; 5461556Srgrimes struct job *jp; 5471556Srgrimes struct stackmark smark; /* unnecessary */ 5481556Srgrimes 5491556Srgrimes setstackmark(&smark); 5501556Srgrimes result->fd = -1; 5511556Srgrimes result->buf = NULL; 5521556Srgrimes result->nleft = 0; 5531556Srgrimes result->jp = NULL; 55417987Speter if (n == NULL) { 55517987Speter exitstatus = 0; 5561556Srgrimes goto out; 55717987Speter } 5581556Srgrimes if (n->type == NCMD) { 55917987Speter exitstatus = oexitstatus; 5601556Srgrimes evalcommand(n, EV_BACKCMD, result); 5611556Srgrimes } else { 56217987Speter exitstatus = 0; 5631556Srgrimes if (pipe(pip) < 0) 56453891Scracauer error("Pipe call failed: %s", strerror(errno)); 5651556Srgrimes jp = makejob(n, 1); 5661556Srgrimes if (forkshell(jp, n, FORK_NOJOB) == 0) { 5671556Srgrimes FORCEINTON; 5681556Srgrimes close(pip[0]); 5691556Srgrimes if (pip[1] != 1) { 5701556Srgrimes close(1); 5711556Srgrimes copyfd(pip[1], 1); 5721556Srgrimes close(pip[1]); 5731556Srgrimes } 5741556Srgrimes evaltree(n, EV_EXIT); 5751556Srgrimes } 5761556Srgrimes close(pip[1]); 5771556Srgrimes result->fd = pip[0]; 5781556Srgrimes result->jp = jp; 5791556Srgrimes } 5801556Srgrimesout: 5811556Srgrimes popstackmark(&smark); 5821556Srgrimes TRACE(("evalbackcmd done: fd=%d buf=0x%x nleft=%d jp=0x%x\n", 5831556Srgrimes result->fd, result->buf, result->nleft, result->jp)); 5841556Srgrimes} 5851556Srgrimes 5861556Srgrimes 5871556Srgrimes 5881556Srgrimes/* 5891556Srgrimes * Execute a simple command. 5901556Srgrimes */ 5911556Srgrimes 5921556SrgrimesSTATIC void 59390111Simpevalcommand(union node *cmd, int flags, struct backcmd *backcmd) 59417987Speter{ 5951556Srgrimes struct stackmark smark; 5961556Srgrimes union node *argp; 5971556Srgrimes struct arglist arglist; 5981556Srgrimes struct arglist varlist; 5991556Srgrimes char **argv; 6001556Srgrimes int argc; 6011556Srgrimes char **envp; 6021556Srgrimes int varflag; 6031556Srgrimes struct strlist *sp; 6041556Srgrimes int mode; 6051556Srgrimes int pip[2]; 6061556Srgrimes struct cmdentry cmdentry; 6071556Srgrimes struct job *jp; 6081556Srgrimes struct jmploc jmploc; 6091556Srgrimes struct jmploc *volatile savehandler; 6101556Srgrimes char *volatile savecmdname; 6111556Srgrimes volatile struct shparam saveparam; 6121556Srgrimes struct localvar *volatile savelocalvars; 6131556Srgrimes volatile int e; 6141556Srgrimes char *lastarg; 61545916Scracauer int realstatus; 61654884Scracauer int do_clearcmdentry; 61717987Speter#if __GNUC__ 61817987Speter /* Avoid longjmp clobbering */ 61917987Speter (void) &argv; 62017987Speter (void) &argc; 62117987Speter (void) &lastarg; 62217987Speter (void) &flags; 62354884Scracauer (void) &do_clearcmdentry; 62417987Speter#endif 6251556Srgrimes 6261556Srgrimes /* First expand the arguments. */ 62717987Speter TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags)); 6281556Srgrimes setstackmark(&smark); 6291556Srgrimes arglist.lastp = &arglist.list; 6301556Srgrimes varlist.lastp = &varlist.list; 6311556Srgrimes varflag = 1; 63254884Scracauer do_clearcmdentry = 0; 63317987Speter oexitstatus = exitstatus; 63417987Speter exitstatus = 0; 6351556Srgrimes for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) { 63617987Speter char *p = argp->narg.text; 6371556Srgrimes if (varflag && is_name(*p)) { 6381556Srgrimes do { 6391556Srgrimes p++; 6401556Srgrimes } while (is_in_name(*p)); 6411556Srgrimes if (*p == '=') { 6421556Srgrimes expandarg(argp, &varlist, EXP_VARTILDE); 6431556Srgrimes continue; 6441556Srgrimes } 6451556Srgrimes } 6461556Srgrimes expandarg(argp, &arglist, EXP_FULL | EXP_TILDE); 6471556Srgrimes varflag = 0; 6481556Srgrimes } 6491556Srgrimes *arglist.lastp = NULL; 6501556Srgrimes *varlist.lastp = NULL; 6511556Srgrimes expredir(cmd->ncmd.redirect); 6521556Srgrimes argc = 0; 6531556Srgrimes for (sp = arglist.list ; sp ; sp = sp->next) 6541556Srgrimes argc++; 6551556Srgrimes argv = stalloc(sizeof (char *) * (argc + 1)); 6561556Srgrimes 6571556Srgrimes for (sp = arglist.list ; sp ; sp = sp->next) { 6581556Srgrimes TRACE(("evalcommand arg: %s\n", sp->text)); 6591556Srgrimes *argv++ = sp->text; 6601556Srgrimes } 6611556Srgrimes *argv = NULL; 6621556Srgrimes lastarg = NULL; 6631556Srgrimes if (iflag && funcnest == 0 && argc > 0) 6641556Srgrimes lastarg = argv[-1]; 6651556Srgrimes argv -= argc; 6661556Srgrimes 6671556Srgrimes /* Print the command if xflag is set. */ 6681556Srgrimes if (xflag) { 6691556Srgrimes outc('+', &errout); 6701556Srgrimes for (sp = varlist.list ; sp ; sp = sp->next) { 6711556Srgrimes outc(' ', &errout); 6721556Srgrimes out2str(sp->text); 6731556Srgrimes } 6741556Srgrimes for (sp = arglist.list ; sp ; sp = sp->next) { 6751556Srgrimes outc(' ', &errout); 6761556Srgrimes out2str(sp->text); 6771556Srgrimes } 6781556Srgrimes outc('\n', &errout); 6791556Srgrimes flushout(&errout); 6801556Srgrimes } 6811556Srgrimes 6821556Srgrimes /* Now locate the command. */ 6831556Srgrimes if (argc == 0) { 6841556Srgrimes cmdentry.cmdtype = CMDBUILTIN; 6851556Srgrimes cmdentry.u.index = BLTINCMD; 6861556Srgrimes } else { 68717987Speter static const char PATH[] = "PATH="; 68817987Speter char *path = pathval(); 68917987Speter 69017987Speter /* 69117987Speter * Modify the command lookup path, if a PATH= assignment 69217987Speter * is present 69317987Speter */ 69417987Speter for (sp = varlist.list ; sp ; sp = sp->next) 69554884Scracauer if (strncmp(sp->text, PATH, sizeof(PATH) - 1) == 0) { 69617987Speter path = sp->text + sizeof(PATH) - 1; 69754884Scracauer /* 69854884Scracauer * On `PATH=... command`, we need to make 69954884Scracauer * sure that the command isn't using the 70054884Scracauer * non-updated hash table of the outer PATH 70154884Scracauer * setting and we need to make sure that 70254884Scracauer * the hash table isn't filled with items 70354884Scracauer * from the temporary setting. 70454884Scracauer * 70554884Scracauer * It would be better to forbit using and 70654884Scracauer * updating the table while this command 70754884Scracauer * runs, by the command finding mechanism 70854884Scracauer * is heavily integrated with hash handling, 70954884Scracauer * so we just delete the hash before and after 71054884Scracauer * the command runs. Partly deleting like 71154884Scracauer * changepatch() does doesn't seem worth the 71254884Scracauer * bookinging effort, since most such runs add 71354884Scracauer * diretories in front of the new PATH. 71454884Scracauer */ 71554884Scracauer clearcmdentry(0); 71654884Scracauer do_clearcmdentry = 1; 71754884Scracauer } 71817987Speter 71917987Speter find_command(argv[0], &cmdentry, 1, path); 7201556Srgrimes if (cmdentry.cmdtype == CMDUNKNOWN) { /* command not found */ 72120425Ssteve exitstatus = 127; 7221556Srgrimes flushout(&errout); 7231556Srgrimes return; 7241556Srgrimes } 7251556Srgrimes /* implement the bltin builtin here */ 7261556Srgrimes if (cmdentry.cmdtype == CMDBUILTIN && cmdentry.u.index == BLTINCMD) { 7271556Srgrimes for (;;) { 7281556Srgrimes argv++; 7291556Srgrimes if (--argc == 0) 7301556Srgrimes break; 7311556Srgrimes if ((cmdentry.u.index = find_builtin(*argv)) < 0) { 7321556Srgrimes outfmt(&errout, "%s: not found\n", *argv); 73320425Ssteve exitstatus = 127; 7341556Srgrimes flushout(&errout); 7351556Srgrimes return; 7361556Srgrimes } 7371556Srgrimes if (cmdentry.u.index != BLTINCMD) 7381556Srgrimes break; 7391556Srgrimes } 7401556Srgrimes } 7411556Srgrimes } 7421556Srgrimes 7431556Srgrimes /* Fork off a child process if necessary. */ 7441556Srgrimes if (cmd->ncmd.backgnd 74545221Scracauer || (cmdentry.cmdtype == CMDNORMAL 74645221Scracauer && ((flags & EV_EXIT) == 0 || Tflag)) 74717987Speter || ((flags & EV_BACKCMD) != 0 7481556Srgrimes && (cmdentry.cmdtype != CMDBUILTIN 74948896Ssheldonh || cmdentry.u.index == CDCMD 7501556Srgrimes || cmdentry.u.index == DOTCMD 751100437Stjr || cmdentry.u.index == EVALCMD)) 752100437Stjr || (cmdentry.cmdtype == CMDBUILTIN && 753100437Stjr cmdentry.u.index == COMMANDCMD)) { 7541556Srgrimes jp = makejob(cmd, 1); 7551556Srgrimes mode = cmd->ncmd.backgnd; 7561556Srgrimes if (flags & EV_BACKCMD) { 7571556Srgrimes mode = FORK_NOJOB; 7581556Srgrimes if (pipe(pip) < 0) 75953891Scracauer error("Pipe call failed: %s", strerror(errno)); 7601556Srgrimes } 7611556Srgrimes if (forkshell(jp, cmd, mode) != 0) 7621556Srgrimes goto parent; /* at end of routine */ 7631556Srgrimes if (flags & EV_BACKCMD) { 7641556Srgrimes FORCEINTON; 7651556Srgrimes close(pip[0]); 7661556Srgrimes if (pip[1] != 1) { 7671556Srgrimes close(1); 7681556Srgrimes copyfd(pip[1], 1); 7691556Srgrimes close(pip[1]); 7701556Srgrimes } 7711556Srgrimes } 7721556Srgrimes flags |= EV_EXIT; 7731556Srgrimes } 7741556Srgrimes 7751556Srgrimes /* This is the child process if a fork occurred. */ 7761556Srgrimes /* Execute the command. */ 7771556Srgrimes if (cmdentry.cmdtype == CMDFUNCTION) { 77820425Ssteve#ifdef DEBUG 7791556Srgrimes trputs("Shell function: "); trargs(argv); 78020425Ssteve#endif 7811556Srgrimes redirect(cmd->ncmd.redirect, REDIR_PUSH); 7821556Srgrimes saveparam = shellparam; 7831556Srgrimes shellparam.malloc = 0; 78420425Ssteve shellparam.reset = 1; 7851556Srgrimes shellparam.nparam = argc - 1; 7861556Srgrimes shellparam.p = argv + 1; 7871556Srgrimes shellparam.optnext = NULL; 7881556Srgrimes INTOFF; 7891556Srgrimes savelocalvars = localvars; 7901556Srgrimes localvars = NULL; 7911556Srgrimes INTON; 7921556Srgrimes if (setjmp(jmploc.loc)) { 7931556Srgrimes if (exception == EXSHELLPROC) 7941556Srgrimes freeparam((struct shparam *)&saveparam); 7951556Srgrimes else { 7961556Srgrimes freeparam(&shellparam); 7971556Srgrimes shellparam = saveparam; 7981556Srgrimes } 7991556Srgrimes poplocalvars(); 8001556Srgrimes localvars = savelocalvars; 8011556Srgrimes handler = savehandler; 8021556Srgrimes longjmp(handler->loc, 1); 8031556Srgrimes } 8041556Srgrimes savehandler = handler; 8051556Srgrimes handler = &jmploc; 8061556Srgrimes for (sp = varlist.list ; sp ; sp = sp->next) 8071556Srgrimes mklocal(sp->text); 8081556Srgrimes funcnest++; 80935675Scracauer if (flags & EV_TESTED) 81035675Scracauer evaltree(cmdentry.u.func, EV_TESTED); 81135675Scracauer else 81235675Scracauer evaltree(cmdentry.u.func, 0); 8131556Srgrimes funcnest--; 8141556Srgrimes INTOFF; 8151556Srgrimes poplocalvars(); 8161556Srgrimes localvars = savelocalvars; 8171556Srgrimes freeparam(&shellparam); 8181556Srgrimes shellparam = saveparam; 8191556Srgrimes handler = savehandler; 8201556Srgrimes popredir(); 8211556Srgrimes INTON; 8221556Srgrimes if (evalskip == SKIPFUNC) { 8231556Srgrimes evalskip = 0; 8241556Srgrimes skipcount = 0; 8251556Srgrimes } 8261556Srgrimes if (flags & EV_EXIT) 8271556Srgrimes exitshell(exitstatus); 8281556Srgrimes } else if (cmdentry.cmdtype == CMDBUILTIN) { 82920425Ssteve#ifdef DEBUG 8301556Srgrimes trputs("builtin command: "); trargs(argv); 83120425Ssteve#endif 8321556Srgrimes mode = (cmdentry.u.index == EXECCMD)? 0 : REDIR_PUSH; 8331556Srgrimes if (flags == EV_BACKCMD) { 8341556Srgrimes memout.nleft = 0; 8351556Srgrimes memout.nextc = memout.buf; 8361556Srgrimes memout.bufsize = 64; 8371556Srgrimes mode |= REDIR_BACKQ; 8381556Srgrimes } 8391556Srgrimes redirect(cmd->ncmd.redirect, mode); 8401556Srgrimes savecmdname = commandname; 8411556Srgrimes cmdenviron = varlist.list; 8421556Srgrimes e = -1; 8431556Srgrimes if (setjmp(jmploc.loc)) { 8441556Srgrimes e = exception; 8451556Srgrimes exitstatus = (e == EXINT)? SIGINT+128 : 2; 8461556Srgrimes goto cmddone; 8471556Srgrimes } 8481556Srgrimes savehandler = handler; 8491556Srgrimes handler = &jmploc; 8501556Srgrimes commandname = argv[0]; 8511556Srgrimes argptr = argv + 1; 8521556Srgrimes optptr = NULL; /* initialize nextopt */ 8531556Srgrimes exitstatus = (*builtinfunc[cmdentry.u.index])(argc, argv); 8541556Srgrimes flushall(); 8551556Srgrimescmddone: 85660592Scracauer cmdenviron = NULL; 8571556Srgrimes out1 = &output; 8581556Srgrimes out2 = &errout; 8591556Srgrimes freestdout(); 8601556Srgrimes if (e != EXSHELLPROC) { 8611556Srgrimes commandname = savecmdname; 8621556Srgrimes if (flags & EV_EXIT) { 8631556Srgrimes exitshell(exitstatus); 8641556Srgrimes } 8651556Srgrimes } 8661556Srgrimes handler = savehandler; 8671556Srgrimes if (e != -1) { 86820425Ssteve if ((e != EXERROR && e != EXEXEC) 86920425Ssteve || cmdentry.u.index == BLTINCMD 87020425Ssteve || cmdentry.u.index == DOTCMD 87120425Ssteve || cmdentry.u.index == EVALCMD 87217987Speter#ifndef NO_HISTORY 87320425Ssteve || cmdentry.u.index == HISTCMD 87417987Speter#endif 875100437Stjr || cmdentry.u.index == EXECCMD 876100437Stjr || cmdentry.u.index == COMMANDCMD) 8771556Srgrimes exraise(e); 8781556Srgrimes FORCEINTON; 8791556Srgrimes } 8801556Srgrimes if (cmdentry.u.index != EXECCMD) 8811556Srgrimes popredir(); 8821556Srgrimes if (flags == EV_BACKCMD) { 8831556Srgrimes backcmd->buf = memout.buf; 8841556Srgrimes backcmd->nleft = memout.nextc - memout.buf; 8851556Srgrimes memout.buf = NULL; 8861556Srgrimes } 8871556Srgrimes } else { 88820425Ssteve#ifdef DEBUG 8891556Srgrimes trputs("normal command: "); trargs(argv); 89020425Ssteve#endif 8911556Srgrimes clearredir(); 8921556Srgrimes redirect(cmd->ncmd.redirect, 0); 8931556Srgrimes for (sp = varlist.list ; sp ; sp = sp->next) 8941556Srgrimes setvareq(sp->text, VEXPORT|VSTACK); 8951556Srgrimes envp = environment(); 89617987Speter shellexec(argv, envp, pathval(), cmdentry.u.index); 8971556Srgrimes /*NOTREACHED*/ 8981556Srgrimes } 8991556Srgrimes goto out; 9001556Srgrimes 9011556Srgrimesparent: /* parent process gets here (if we forked) */ 9021556Srgrimes if (mode == 0) { /* argument to fork */ 9031556Srgrimes INTOFF; 90445916Scracauer exitstatus = waitforjob(jp, &realstatus); 9051556Srgrimes INTON; 90645916Scracauer if (iflag && loopnest > 0 && WIFSIGNALED(realstatus)) { 90745266Scracauer evalskip = SKIPBREAK; 90845266Scracauer skipcount = loopnest; 90945266Scracauer } 9101556Srgrimes } else if (mode == 2) { 9111556Srgrimes backcmd->fd = pip[0]; 9121556Srgrimes close(pip[1]); 9131556Srgrimes backcmd->jp = jp; 9141556Srgrimes } 9151556Srgrimes 9161556Srgrimesout: 9171556Srgrimes if (lastarg) 9181556Srgrimes setvar("_", lastarg, 0); 91954884Scracauer if (do_clearcmdentry) 92054884Scracauer clearcmdentry(0); 9211556Srgrimes popstackmark(&smark); 9221556Srgrimes} 9231556Srgrimes 9241556Srgrimes 9251556Srgrimes 9261556Srgrimes/* 9271556Srgrimes * Search for a command. This is called before we fork so that the 9281556Srgrimes * location of the command will be available in the parent as well as 9291556Srgrimes * the child. The check for "goodname" is an overly conservative 9301556Srgrimes * check that the name will not be subject to expansion. 9311556Srgrimes */ 9321556Srgrimes 9331556SrgrimesSTATIC void 93490111Simpprehash(union node *n) 93517987Speter{ 9361556Srgrimes struct cmdentry entry; 9371556Srgrimes 93817987Speter if (n->type == NCMD && n->ncmd.args) 93917987Speter if (goodname(n->ncmd.args->narg.text)) 94017987Speter find_command(n->ncmd.args->narg.text, &entry, 0, 94117987Speter pathval()); 9421556Srgrimes} 9431556Srgrimes 9441556Srgrimes 9451556Srgrimes 9461556Srgrimes/* 9471556Srgrimes * Builtin commands. Builtin commands whose functions are closely 9481556Srgrimes * tied to evaluation are implemented here. 9491556Srgrimes */ 9501556Srgrimes 9511556Srgrimes/* 9521556Srgrimes * No command given, or a bltin command with no arguments. Set the 9531556Srgrimes * specified variables. 9541556Srgrimes */ 9551556Srgrimes 95617987Speterint 95790111Simpbltincmd(int argc __unused, char **argv __unused) 95817987Speter{ 9591556Srgrimes listsetvar(cmdenviron); 96020425Ssteve /* 96117987Speter * Preserve exitstatus of a previous possible redirection 96220425Ssteve * as POSIX mandates 96317987Speter */ 9641556Srgrimes return exitstatus; 9651556Srgrimes} 9661556Srgrimes 9671556Srgrimes 9681556Srgrimes/* 9691556Srgrimes * Handle break and continue commands. Break, continue, and return are 9701556Srgrimes * all handled by setting the evalskip flag. The evaluation routines 9711556Srgrimes * above all check this flag, and if it is set they start skipping 9721556Srgrimes * commands rather than executing them. The variable skipcount is 9731556Srgrimes * the number of loops to break/continue, or the number of function 9741556Srgrimes * levels to return. (The latter is always 1.) It should probably 9751556Srgrimes * be an error to break out of more loops than exist, but it isn't 9761556Srgrimes * in the standard shell so we don't make it one here. 9771556Srgrimes */ 9781556Srgrimes 97917987Speterint 98090111Simpbreakcmd(int argc, char **argv) 98117987Speter{ 98220425Ssteve int n = argc > 1 ? number(argv[1]) : 1; 9831556Srgrimes 9841556Srgrimes if (n > loopnest) 9851556Srgrimes n = loopnest; 9861556Srgrimes if (n > 0) { 9871556Srgrimes evalskip = (**argv == 'c')? SKIPCONT : SKIPBREAK; 9881556Srgrimes skipcount = n; 9891556Srgrimes } 9901556Srgrimes return 0; 9911556Srgrimes} 9921556Srgrimes 993100437Stjr/* 994100437Stjr * The `command' command. 995100437Stjr */ 996100437Stjrint 997100437Stjrcommandcmd(int argc, char **argv) 998100437Stjr{ 999100437Stjr static char stdpath[] = _PATH_STDPATH; 1000100437Stjr struct jmploc loc, *old; 1001100437Stjr struct strlist *sp; 1002100437Stjr char *path; 1003100437Stjr int ch; 10041556Srgrimes 1005100437Stjr for (sp = cmdenviron; sp ; sp = sp->next) 1006100437Stjr setvareq(sp->text, VEXPORT|VSTACK); 1007100437Stjr path = pathval(); 1008100437Stjr 1009100437Stjr optind = optreset = 1; 1010100437Stjr while ((ch = getopt(argc, argv, "p")) != -1) { 1011100437Stjr switch (ch) { 1012100437Stjr case 'p': 1013100437Stjr path = stdpath; 1014100437Stjr break; 1015100437Stjr case '?': 1016100437Stjr default: 1017100437Stjr error("unknown option: -%c", optopt); 1018100437Stjr } 1019100437Stjr } 1020100437Stjr argc -= optind; 1021100437Stjr argv += optind; 1022100437Stjr 1023100437Stjr if (argc != 0) { 1024100437Stjr old = handler; 1025100437Stjr handler = &loc; 1026100437Stjr if (setjmp(handler->loc) == 0) 1027100437Stjr shellexec(argv, environment(), path, 0); 1028100437Stjr handler = old; 1029100437Stjr if (exception == EXEXEC) 1030100437Stjr exit(exerrno); 1031100437Stjr exraise(exception); 1032100437Stjr } 1033100437Stjr 1034100437Stjr /* 1035100437Stjr * Do nothing successfully if no command was specified; 1036100437Stjr * ksh also does this. 1037100437Stjr */ 1038100437Stjr exit(0); 1039100437Stjr} 1040100437Stjr 1041100437Stjr 10421556Srgrimes/* 10431556Srgrimes * The return command. 10441556Srgrimes */ 10451556Srgrimes 104617987Speterint 104790111Simpreturncmd(int argc, char **argv) 104817987Speter{ 104920425Ssteve int ret = argc > 1 ? number(argv[1]) : oexitstatus; 10501556Srgrimes 10511556Srgrimes if (funcnest) { 10521556Srgrimes evalskip = SKIPFUNC; 10531556Srgrimes skipcount = 1; 105420425Ssteve } else { 105520425Ssteve /* skip the rest of the file */ 105620425Ssteve evalskip = SKIPFILE; 105720425Ssteve skipcount = 1; 10581556Srgrimes } 10591556Srgrimes return ret; 10601556Srgrimes} 10611556Srgrimes 10621556Srgrimes 106317987Speterint 106490111Simpfalsecmd(int argc __unused, char **argv __unused) 106517987Speter{ 106617987Speter return 1; 106717987Speter} 106817987Speter 106917987Speter 107017987Speterint 107190111Simptruecmd(int argc __unused, char **argv __unused) 107217987Speter{ 10731556Srgrimes return 0; 10741556Srgrimes} 10751556Srgrimes 10761556Srgrimes 107717987Speterint 107890111Simpexeccmd(int argc, char **argv) 107917987Speter{ 10801556Srgrimes if (argc > 1) { 108117987Speter struct strlist *sp; 108217987Speter 10831556Srgrimes iflag = 0; /* exit on error */ 10841556Srgrimes mflag = 0; 10851556Srgrimes optschanged(); 108617987Speter for (sp = cmdenviron; sp ; sp = sp->next) 108717987Speter setvareq(sp->text, VEXPORT|VSTACK); 10881556Srgrimes shellexec(argv + 1, environment(), pathval(), 0); 10891556Srgrimes 10901556Srgrimes } 10911556Srgrimes return 0; 10921556Srgrimes} 1093