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-rw-r--r--bin/catsh/eval.c1381
1 files changed, 0 insertions, 1381 deletions
diff --git a/bin/catsh/eval.c b/bin/catsh/eval.c
deleted file mode 100644
index 5a5289e1..00000000
--- a/bin/catsh/eval.c
+++ /dev/null
@@ -1,1381 +0,0 @@
-/*-
- * Copyright (c) 1993
- *	The Regents of the University of California.  All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Kenneth Almquist.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the University nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#ifndef lint
-#if 0
-static char sccsid[] = "@(#)eval.c	8.9 (Berkeley) 6/8/95";
-#endif
-#endif /* not lint */
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: releng/12.0/bin/sh/eval.c 327212 2017-12-26 16:23:18Z jilles $");
-
-#include <paths.h>
-#include <signal.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/resource.h>
-#include <errno.h>
-
-/*
- * Evaluate a command.
- */
-
-#include "shell.h"
-#include "nodes.h"
-#include "syntax.h"
-#include "expand.h"
-#include "parser.h"
-#include "jobs.h"
-#include "eval.h"
-#include "builtins.h"
-#include "options.h"
-#include "exec.h"
-#include "redir.h"
-#include "input.h"
-#include "output.h"
-#include "trap.h"
-#include "var.h"
-#include "memalloc.h"
-#include "error.h"
-#include "show.h"
-#include "mystring.h"
-#ifndef NO_HISTORY
-#include "myhistedit.h"
-#endif
-
-
-int evalskip;			/* set if we are skipping commands */
-int skipcount;			/* number of levels to skip */
-static int loopnest;		/* current loop nesting level */
-int funcnest;			/* depth of function calls */
-static int builtin_flags;	/* evalcommand flags for builtins */
-
-
-char *commandname;
-struct arglist *cmdenviron;
-int exitstatus;			/* exit status of last command */
-int oexitstatus;		/* saved exit status */
-
-
-static void evalloop(union node *, int);
-static void evalfor(union node *, int);
-static union node *evalcase(union node *);
-static void evalsubshell(union node *, int);
-static void evalredir(union node *, int);
-static void exphere(union node *, struct arglist *);
-static void expredir(union node *);
-static void evalpipe(union node *);
-static int is_valid_fast_cmdsubst(union node *n);
-static void evalcommand(union node *, int, struct backcmd *);
-static void prehash(union node *);
-
-
-/*
- * Called to reset things after an exception.
- */
-
-void
-reseteval(void)
-{
-	evalskip = 0;
-	loopnest = 0;
-}
-
-
-/*
- * The eval command.
- */
-
-int
-evalcmd(int argc, char **argv)
-{
-        char *p;
-        char *concat;
-        char **ap;
-
-        if (argc > 1) {
-                p = argv[1];
-                if (argc > 2) {
-                        STARTSTACKSTR(concat);
-                        ap = argv + 2;
-                        for (;;) {
-                                STPUTS(p, concat);
-                                if ((p = *ap++) == NULL)
-                                        break;
-                                STPUTC(' ', concat);
-                        }
-                        STPUTC('\0', concat);
-                        p = grabstackstr(concat);
-                }
-                evalstring(p, builtin_flags);
-        } else
-                exitstatus = 0;
-        return exitstatus;
-}
-
-
-/*
- * Execute a command or commands contained in a string.
- */
-
-void
-evalstring(const char *s, int flags)
-{
-	union node *n;
-	struct stackmark smark;
-	int flags_exit;
-	int any;
-
-	flags_exit = flags & EV_EXIT;
-	flags &= ~EV_EXIT;
-	any = 0;
-	setstackmark(&smark);
-	setinputstring(s, 1);
-	while ((n = parsecmd(0)) != NEOF) {
-		if (n != NULL && !nflag) {
-			if (flags_exit && preadateof())
-				evaltree(n, flags | EV_EXIT);
-			else
-				evaltree(n, flags);
-			any = 1;
-			if (evalskip)
-				break;
-		}
-		popstackmark(&smark);
-		setstackmark(&smark);
-	}
-	popfile();
-	popstackmark(&smark);
-	if (!any)
-		exitstatus = 0;
-	if (flags_exit)
-		exraise(EXEXIT);
-}
-
-
-/*
- * Evaluate a parse tree.  The value is left in the global variable
- * exitstatus.
- */
-
-void
-evaltree(union node *n, int flags)
-{
-	int do_etest;
-	union node *next;
-	struct stackmark smark;
-
-	setstackmark(&smark);
-	do_etest = 0;
-	if (n == NULL) {
-		TRACE(("evaltree(NULL) called\n"));
-		exitstatus = 0;
-		goto out;
-	}
-	do {
-		next = NULL;
-#ifndef NO_HISTORY
-		displayhist = 1;	/* show history substitutions done with fc */
-#endif
-		TRACE(("evaltree(%p: %d) called\n", (void *)n, n->type));
-		switch (n->type) {
-		case NSEMI:
-			evaltree(n->nbinary.ch1, flags & ~EV_EXIT);
-			if (evalskip)
-				goto out;
-			next = n->nbinary.ch2;
-			break;
-		case NAND:
-			evaltree(n->nbinary.ch1, EV_TESTED);
-			if (evalskip || exitstatus != 0) {
-				goto out;
-			}
-			next = n->nbinary.ch2;
-			break;
-		case NOR:
-			evaltree(n->nbinary.ch1, EV_TESTED);
-			if (evalskip || exitstatus == 0)
-				goto out;
-			next = n->nbinary.ch2;
-			break;
-		case NREDIR:
-			evalredir(n, flags);
-			break;
-		case NSUBSHELL:
-			evalsubshell(n, flags);
-			do_etest = !(flags & EV_TESTED);
-			break;
-		case NBACKGND:
-			evalsubshell(n, flags);
-			break;
-		case NIF: {
-			evaltree(n->nif.test, EV_TESTED);
-			if (evalskip)
-				goto out;
-			if (exitstatus == 0)
-				next = n->nif.ifpart;
-			else if (n->nif.elsepart)
-				next = n->nif.elsepart;
-			else
-				exitstatus = 0;
-			break;
-		}
-		case NWHILE:
-		case NUNTIL:
-			evalloop(n, flags & ~EV_EXIT);
-			break;
-		case NFOR:
-			evalfor(n, flags & ~EV_EXIT);
-			break;
-		case NCASE:
-			next = evalcase(n);
-			break;
-		case NCLIST:
-			next = n->nclist.body;
-			break;
-		case NCLISTFALLTHRU:
-			if (n->nclist.body) {
-				evaltree(n->nclist.body, flags & ~EV_EXIT);
-				if (evalskip)
-					goto out;
-			}
-			next = n->nclist.next;
-			break;
-		case NDEFUN:
-			defun(n->narg.text, n->narg.next);
-			exitstatus = 0;
-			break;
-		case NNOT:
-			evaltree(n->nnot.com, EV_TESTED);
-			if (evalskip)
-				goto out;
-			exitstatus = !exitstatus;
-			break;
-
-		case NPIPE:
-			evalpipe(n);
-			do_etest = !(flags & EV_TESTED);
-			break;
-		case NCMD:
-			evalcommand(n, flags, (struct backcmd *)NULL);
-			do_etest = !(flags & EV_TESTED);
-			break;
-		default:
-			out1fmt("Node type = %d\n", n->type);
-			flushout(&output);
-			break;
-		}
-		n = next;
-		popstackmark(&smark);
-		setstackmark(&smark);
-	} while (n != NULL);
-out:
-	popstackmark(&smark);
-	if (pendingsig)
-		dotrap();
-	if (eflag && exitstatus != 0 && do_etest)
-		exitshell(exitstatus);
-	if (flags & EV_EXIT)
-		exraise(EXEXIT);
-}
-
-
-static void
-evalloop(union node *n, int flags)
-{
-	int status;
-
-	loopnest++;
-	status = 0;
-	for (;;) {
-		if (!evalskip)
-			evaltree(n->nbinary.ch1, EV_TESTED);
-		if (evalskip) {
-			if (evalskip == SKIPCONT && --skipcount <= 0) {
-				evalskip = 0;
-				continue;
-			}
-			if (evalskip == SKIPBREAK && --skipcount <= 0)
-				evalskip = 0;
-			if (evalskip == SKIPRETURN)
-				status = exitstatus;
-			break;
-		}
-		if (n->type == NWHILE) {
-			if (exitstatus != 0)
-				break;
-		} else {
-			if (exitstatus == 0)
-				break;
-		}
-		evaltree(n->nbinary.ch2, flags);
-		status = exitstatus;
-	}
-	loopnest--;
-	exitstatus = status;
-}
-
-
-
-static void
-evalfor(union node *n, int flags)
-{
-	struct arglist arglist;
-	union node *argp;
-	int i;
-	int status;
-
-	emptyarglist(&arglist);
-	for (argp = n->nfor.args ; argp ; argp = argp->narg.next) {
-		oexitstatus = exitstatus;
-		expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
-	}
-
-	loopnest++;
-	status = 0;
-	for (i = 0; i < arglist.count; i++) {
-		setvar(n->nfor.var, arglist.args[i], 0);
-		evaltree(n->nfor.body, flags);
-		status = exitstatus;
-		if (evalskip) {
-			if (evalskip == SKIPCONT && --skipcount <= 0) {
-				evalskip = 0;
-				continue;
-			}
-			if (evalskip == SKIPBREAK && --skipcount <= 0)
-				evalskip = 0;
-			break;
-		}
-	}
-	loopnest--;
-	exitstatus = status;
-}
-
-
-/*
- * Evaluate a case statement, returning the selected tree.
- *
- * The exit status needs care to get right.
- */
-
-static union node *
-evalcase(union node *n)
-{
-	union node *cp;
-	union node *patp;
-	struct arglist arglist;
-
-	emptyarglist(&arglist);
-	oexitstatus = exitstatus;
-	expandarg(n->ncase.expr, &arglist, EXP_TILDE);
-	for (cp = n->ncase.cases ; cp ; cp = cp->nclist.next) {
-		for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) {
-			if (casematch(patp, arglist.args[0])) {
-				while (cp->nclist.next &&
-				    cp->type == NCLISTFALLTHRU &&
-				    cp->nclist.body == NULL)
-					cp = cp->nclist.next;
-				if (cp->nclist.next &&
-				    cp->type == NCLISTFALLTHRU)
-					return (cp);
-				if (cp->nclist.body == NULL)
-					exitstatus = 0;
-				return (cp->nclist.body);
-			}
-		}
-	}
-	exitstatus = 0;
-	return (NULL);
-}
-
-
-
-/*
- * Kick off a subshell to evaluate a tree.
- */
-
-static void
-evalsubshell(union node *n, int flags)
-{
-	struct job *jp;
-	int backgnd = (n->type == NBACKGND);
-
-	oexitstatus = exitstatus;
-	expredir(n->nredir.redirect);
-	if ((!backgnd && flags & EV_EXIT && !have_traps()) ||
-			forkshell(jp = makejob(n, 1), n, backgnd) == 0) {
-		if (backgnd)
-			flags &=~ EV_TESTED;
-		redirect(n->nredir.redirect, 0);
-		evaltree(n->nredir.n, flags | EV_EXIT);	/* never returns */
-	} else if (! backgnd) {
-		INTOFF;
-		exitstatus = waitforjob(jp, (int *)NULL);
-		INTON;
-	} else
-		exitstatus = 0;
-}
-
-
-/*
- * Evaluate a redirected compound command.
- */
-
-static void
-evalredir(union node *n, int flags)
-{
-	struct jmploc jmploc;
-	struct jmploc *savehandler;
-	volatile int in_redirect = 1;
-
-	oexitstatus = exitstatus;
-	expredir(n->nredir.redirect);
-	savehandler = handler;
-	if (setjmp(jmploc.loc)) {
-		int e;
-
-		handler = savehandler;
-		e = exception;
-		popredir();
-		if (e == EXERROR || e == EXEXEC) {
-			if (in_redirect) {
-				exitstatus = 2;
-				FORCEINTON;
-				return;
-			}
-		}
-		longjmp(handler->loc, 1);
-	} else {
-		INTOFF;
-		handler = &jmploc;
-		redirect(n->nredir.redirect, REDIR_PUSH);
-		in_redirect = 0;
-		INTON;
-		evaltree(n->nredir.n, flags);
-	}
-	INTOFF;
-	handler = savehandler;
-	popredir();
-	INTON;
-}
-
-
-static void
-exphere(union node *redir, struct arglist *fn)
-{
-	struct jmploc jmploc;
-	struct jmploc *savehandler;
-	struct localvar *savelocalvars;
-	int need_longjmp = 0;
-	unsigned char saveoptreset;
-
-	redir->nhere.expdoc = "";
-	savelocalvars = localvars;
-	localvars = NULL;
-	saveoptreset = shellparam.reset;
-	forcelocal++;
-	savehandler = handler;
-	if (setjmp(jmploc.loc))
-		need_longjmp = exception != EXERROR && exception != EXEXEC;
-	else {
-		handler = &jmploc;
-		expandarg(redir->nhere.doc, fn, 0);
-		redir->nhere.expdoc = fn->args[0];
-		INTOFF;
-	}
-	handler = savehandler;
-	forcelocal--;
-	poplocalvars();
-	localvars = savelocalvars;
-	shellparam.reset = saveoptreset;
-	if (need_longjmp)
-		longjmp(handler->loc, 1);
-	INTON;
-}
-
-
-/*
- * Compute the names of the files in a redirection list.
- */
-
-static void
-expredir(union node *n)
-{
-	union node *redir;
-
-	for (redir = n ; redir ; redir = redir->nfile.next) {
-		struct arglist fn;
-		emptyarglist(&fn);
-		switch (redir->type) {
-		case NFROM:
-		case NTO:
-		case NFROMTO:
-		case NAPPEND:
-		case NCLOBBER:
-			expandarg(redir->nfile.fname, &fn, EXP_TILDE);
-			redir->nfile.expfname = fn.args[0];
-			break;
-		case NFROMFD:
-		case NTOFD:
-			if (redir->ndup.vname) {
-				expandarg(redir->ndup.vname, &fn, EXP_TILDE);
-				fixredir(redir, fn.args[0], 1);
-			}
-			break;
-		case NXHERE:
-			exphere(redir, &fn);
-			break;
-		}
-	}
-}
-
-
-
-/*
- * Evaluate a pipeline.  All the processes in the pipeline are children
- * of the process creating the pipeline.  (This differs from some versions
- * of the shell, which make the last process in a pipeline the parent
- * of all the rest.)
- */
-
-static void
-evalpipe(union node *n)
-{
-	struct job *jp;
-	struct nodelist *lp;
-	int pipelen;
-	int prevfd;
-	int pip[2];
-
-	TRACE(("evalpipe(%p) called\n", (void *)n));
-	pipelen = 0;
-	for (lp = n->npipe.cmdlist ; lp ; lp = lp->next)
-		pipelen++;
-	INTOFF;
-	jp = makejob(n, pipelen);
-	prevfd = -1;
-	for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
-		prehash(lp->n);
-		pip[1] = -1;
-		if (lp->next) {
-			if (pipe(pip) < 0) {
-				if (prevfd >= 0)
-					close(prevfd);
-				error("Pipe call failed: %s", strerror(errno));
-			}
-		}
-		if (forkshell(jp, lp->n, n->npipe.backgnd) == 0) {
-			INTON;
-			if (prevfd > 0) {
-				dup2(prevfd, 0);
-				close(prevfd);
-			}
-			if (pip[1] >= 0) {
-				if (!(prevfd >= 0 && pip[0] == 0))
-					close(pip[0]);
-				if (pip[1] != 1) {
-					dup2(pip[1], 1);
-					close(pip[1]);
-				}
-			}
-			evaltree(lp->n, EV_EXIT);
-		}
-		if (prevfd >= 0)
-			close(prevfd);
-		prevfd = pip[0];
-		if (pip[1] != -1)
-			close(pip[1]);
-	}
-	INTON;
-	if (n->npipe.backgnd == 0) {
-		INTOFF;
-		exitstatus = waitforjob(jp, (int *)NULL);
-		TRACE(("evalpipe:  job done exit status %d\n", exitstatus));
-		INTON;
-	} else
-		exitstatus = 0;
-}
-
-
-
-static int
-is_valid_fast_cmdsubst(union node *n)
-{
-
-	return (n->type == NCMD);
-}
-
-/*
- * Execute a command inside back quotes.  If it's a builtin command, we
- * want to save its output in a block obtained from malloc.  Otherwise
- * we fork off a subprocess and get the output of the command via a pipe.
- * Should be called with interrupts off.
- */
-
-void
-evalbackcmd(union node *n, struct backcmd *result)
-{
-	int pip[2];
-	struct job *jp;
-	struct stackmark smark;
-	struct jmploc jmploc;
-	struct jmploc *savehandler;
-	struct localvar *savelocalvars;
-	unsigned char saveoptreset;
-
-	result->fd = -1;
-	result->buf = NULL;
-	result->nleft = 0;
-	result->jp = NULL;
-	if (n == NULL) {
-		exitstatus = 0;
-		return;
-	}
-	setstackmark(&smark);
-	exitstatus = oexitstatus;
-	if (is_valid_fast_cmdsubst(n)) {
-		savelocalvars = localvars;
-		localvars = NULL;
-		saveoptreset = shellparam.reset;
-		forcelocal++;
-		savehandler = handler;
-		if (setjmp(jmploc.loc)) {
-			if (exception == EXERROR || exception == EXEXEC)
-				exitstatus = 2;
-			else if (exception != 0) {
-				handler = savehandler;
-				forcelocal--;
-				poplocalvars();
-				localvars = savelocalvars;
-				shellparam.reset = saveoptreset;
-				longjmp(handler->loc, 1);
-			}
-		} else {
-			handler = &jmploc;
-			evalcommand(n, EV_BACKCMD, result);
-		}
-		handler = savehandler;
-		forcelocal--;
-		poplocalvars();
-		localvars = savelocalvars;
-		shellparam.reset = saveoptreset;
-	} else {
-		if (pipe(pip) < 0)
-			error("Pipe call failed: %s", strerror(errno));
-		jp = makejob(n, 1);
-		if (forkshell(jp, n, FORK_NOJOB) == 0) {
-			FORCEINTON;
-			close(pip[0]);
-			if (pip[1] != 1) {
-				dup2(pip[1], 1);
-				close(pip[1]);
-			}
-			evaltree(n, EV_EXIT);
-		}
-		close(pip[1]);
-		result->fd = pip[0];
-		result->jp = jp;
-	}
-	popstackmark(&smark);
-	TRACE(("evalbackcmd done: fd=%d buf=%p nleft=%d jp=%p\n",
-		result->fd, result->buf, result->nleft, result->jp));
-}
-
-static int
-mustexpandto(const char *argtext, const char *mask)
-{
-	for (;;) {
-		if (*argtext == CTLQUOTEMARK || *argtext == CTLQUOTEEND) {
-			argtext++;
-			continue;
-		}
-		if (*argtext == CTLESC)
-			argtext++;
-		else if (BASESYNTAX[(int)*argtext] == CCTL)
-			return (0);
-		if (*argtext != *mask)
-			return (0);
-		if (*argtext == '\0')
-			return (1);
-		argtext++;
-		mask++;
-	}
-}
-
-static int
-isdeclarationcmd(struct narg *arg)
-{
-	int have_command = 0;
-
-	if (arg == NULL)
-		return (0);
-	while (mustexpandto(arg->text, "command")) {
-		have_command = 1;
-		arg = &arg->next->narg;
-		if (arg == NULL)
-			return (0);
-		/*
-		 * To also allow "command -p" and "command --" as part of
-		 * a declaration command, add code here.
-		 * We do not do this, as ksh does not do it either and it
-		 * is not required by POSIX.
-		 */
-	}
-	return (mustexpandto(arg->text, "export") ||
-	    mustexpandto(arg->text, "readonly") ||
-	    (mustexpandto(arg->text, "local") &&
-		(have_command || !isfunc("local"))));
-}
-
-static void
-xtracecommand(struct arglist *varlist, int argc, char **argv)
-{
-	char sep = 0;
-	const char *text, *p, *ps4;
-	int i;
-
-	ps4 = expandstr(ps4val());
-	out2str(ps4 != NULL ? ps4 : ps4val());
-	for (i = 0; i < varlist->count; i++) {
-		text = varlist->args[i];
-		if (sep != 0)
-			out2c(' ');
-		p = strchr(text, '=');
-		if (p != NULL) {
-			p++;
-			outbin(text, p - text, out2);
-			out2qstr(p);
-		} else
-			out2qstr(text);
-		sep = ' ';
-	}
-	for (i = 0; i < argc; i++) {
-		text = argv[i];
-		if (sep != 0)
-			out2c(' ');
-		out2qstr(text);
-		sep = ' ';
-	}
-	out2c('\n');
-	flushout(&errout);
-}
-
-/*
- * Check if a builtin can safely be executed in the same process,
- * even though it should be in a subshell (command substitution).
- * Note that jobid, jobs, times and trap can show information not
- * available in a child process; this is deliberate.
- * The arguments should already have been expanded.
- */
-static int
-safe_builtin(int idx, int argc, char **argv)
-{
-	/* Generated from builtins.def. */
-	if (safe_builtin_always(idx))
-		return (1);
-	if (idx == EXPORTCMD || idx == TRAPCMD || idx == ULIMITCMD ||
-	    idx == UMASKCMD)
-		return (argc <= 1 || (argc == 2 && argv[1][0] == '-'));
-	if (idx == SETCMD)
-		return (argc <= 1 || (argc == 2 && (argv[1][0] == '-' ||
-		    argv[1][0] == '+') && argv[1][1] == 'o' &&
-		    argv[1][2] == '\0'));
-	return (0);
-}
-
-/*
- * Execute a simple command.
- * Note: This may or may not return if (flags & EV_EXIT).
- */
-
-static void
-evalcommand(union node *cmd, int flags, struct backcmd *backcmd)
-{
-	union node *argp;
-	struct arglist arglist;
-	struct arglist varlist;
-	char **argv;
-	int argc;
-	char **envp;
-	int varflag;
-	int mode;
-	int pip[2];
-	struct cmdentry cmdentry;
-	struct job *jp;
-	struct jmploc jmploc;
-	struct jmploc *savehandler;
-	char *savecmdname;
-	struct shparam saveparam;
-	struct localvar *savelocalvars;
-	struct parsefile *savetopfile;
-	volatile int e;
-	char *lastarg;
-	int signaled;
-	int do_clearcmdentry;
-	const char *path = pathval();
-	int i;
-
-	/* First expand the arguments. */
-	TRACE(("evalcommand(%p, %d) called\n", (void *)cmd, flags));
-	emptyarglist(&arglist);
-	emptyarglist(&varlist);
-	varflag = 1;
-	jp = NULL;
-	do_clearcmdentry = 0;
-	oexitstatus = exitstatus;
-	exitstatus = 0;
-	/* Add one slot at the beginning for tryexec(). */
-	appendarglist(&arglist, nullstr);
-	for (argp = cmd->ncmd.args ; argp ; argp = argp->narg.next) {
-		if (varflag && isassignment(argp->narg.text)) {
-			expandarg(argp, varflag == 1 ? &varlist : &arglist,
-			    EXP_VARTILDE);
-			continue;
-		} else if (varflag == 1)
-			varflag = isdeclarationcmd(&argp->narg) ? 2 : 0;
-		expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
-	}
-	appendarglist(&arglist, nullstr);
-	expredir(cmd->ncmd.redirect);
-	argc = arglist.count - 2;
-	argv = &arglist.args[1];
-
-	argv[argc] = NULL;
-	lastarg = NULL;
-	if (iflag && funcnest == 0 && argc > 0)
-		lastarg = argv[argc - 1];
-
-	/* Print the command if xflag is set. */
-	if (xflag)
-		xtracecommand(&varlist, argc, argv);
-
-	/* Now locate the command. */
-	if (argc == 0) {
-		/* Variable assignment(s) without command */
-		cmdentry.cmdtype = CMDBUILTIN;
-		cmdentry.u.index = BLTINCMD;
-		cmdentry.special = 0;
-	} else {
-		static const char PATH[] = "PATH=";
-		int cmd_flags = 0, bltinonly = 0;
-
-		/*
-		 * Modify the command lookup path, if a PATH= assignment
-		 * is present
-		 */
-		for (i = 0; i < varlist.count; i++)
-			if (strncmp(varlist.args[i], PATH, sizeof(PATH) - 1) == 0) {
-				path = varlist.args[i] + sizeof(PATH) - 1;
-				/*
-				 * On `PATH=... command`, we need to make
-				 * sure that the command isn't using the
-				 * non-updated hash table of the outer PATH
-				 * setting and we need to make sure that
-				 * the hash table isn't filled with items
-				 * from the temporary setting.
-				 *
-				 * It would be better to forbit using and
-				 * updating the table while this command
-				 * runs, by the command finding mechanism
-				 * is heavily integrated with hash handling,
-				 * so we just delete the hash before and after
-				 * the command runs. Partly deleting like
-				 * changepatch() does doesn't seem worth the
-				 * bookinging effort, since most such runs add
-				 * directories in front of the new PATH.
-				 */
-				clearcmdentry();
-				do_clearcmdentry = 1;
-			}
-
-		for (;;) {
-			if (bltinonly) {
-				cmdentry.u.index = find_builtin(*argv, &cmdentry.special);
-				if (cmdentry.u.index < 0) {
-					cmdentry.u.index = BLTINCMD;
-					argv--;
-					argc++;
-					break;
-				}
-			} else
-				find_command(argv[0], &cmdentry, cmd_flags, path);
-			/* implement the bltin and command builtins here */
-			if (cmdentry.cmdtype != CMDBUILTIN)
-				break;
-			if (cmdentry.u.index == BLTINCMD) {
-				if (argc == 1)
-					break;
-				argv++;
-				argc--;
-				bltinonly = 1;
-			} else if (cmdentry.u.index == COMMANDCMD) {
-				if (argc == 1)
-					break;
-				if (!strcmp(argv[1], "-p")) {
-					if (argc == 2)
-						break;
-					if (argv[2][0] == '-') {
-						if (strcmp(argv[2], "--"))
-							break;
-						if (argc == 3)
-							break;
-						argv += 3;
-						argc -= 3;
-					} else {
-						argv += 2;
-						argc -= 2;
-					}
-					path = _PATH_STDPATH;
-					clearcmdentry();
-					do_clearcmdentry = 1;
-				} else if (!strcmp(argv[1], "--")) {
-					if (argc == 2)
-						break;
-					argv += 2;
-					argc -= 2;
-				} else if (argv[1][0] == '-')
-					break;
-				else {
-					argv++;
-					argc--;
-				}
-				cmd_flags |= DO_NOFUNC;
-				bltinonly = 0;
-			} else
-				break;
-		}
-		/*
-		 * Special builtins lose their special properties when
-		 * called via 'command'.
-		 */
-		if (cmd_flags & DO_NOFUNC)
-			cmdentry.special = 0;
-	}
-
-	/* Fork off a child process if necessary. */
-	if (((cmdentry.cmdtype == CMDNORMAL || cmdentry.cmdtype == CMDUNKNOWN)
-	    && ((flags & EV_EXIT) == 0 || have_traps()))
-	 || ((flags & EV_BACKCMD) != 0
-	    && (cmdentry.cmdtype != CMDBUILTIN ||
-		 !safe_builtin(cmdentry.u.index, argc, argv)))) {
-		jp = makejob(cmd, 1);
-		mode = FORK_FG;
-		if (flags & EV_BACKCMD) {
-			mode = FORK_NOJOB;
-			if (pipe(pip) < 0)
-				error("Pipe call failed: %s", strerror(errno));
-		}
-		if (cmdentry.cmdtype == CMDNORMAL &&
-		    cmd->ncmd.redirect == NULL &&
-		    varlist.count == 0 &&
-		    (mode == FORK_FG || mode == FORK_NOJOB) &&
-		    !disvforkset() && !iflag && !mflag) {
-			vforkexecshell(jp, argv, environment(), path,
-			    cmdentry.u.index, flags & EV_BACKCMD ? pip : NULL);
-			goto parent;
-		}
-		if (forkshell(jp, cmd, mode) != 0)
-			goto parent;	/* at end of routine */
-		if (flags & EV_BACKCMD) {
-			FORCEINTON;
-			close(pip[0]);
-			if (pip[1] != 1) {
-				dup2(pip[1], 1);
-				close(pip[1]);
-			}
-			flags &= ~EV_BACKCMD;
-		}
-		flags |= EV_EXIT;
-	}
-
-	/* This is the child process if a fork occurred. */
-	/* Execute the command. */
-	if (cmdentry.cmdtype == CMDFUNCTION) {
-#ifdef DEBUG
-		trputs("Shell function:  ");  trargs(argv);
-#endif
-		saveparam = shellparam;
-		shellparam.malloc = 0;
-		shellparam.reset = 1;
-		shellparam.nparam = argc - 1;
-		shellparam.p = argv + 1;
-		shellparam.optp = NULL;
-		shellparam.optnext = NULL;
-		INTOFF;
-		savelocalvars = localvars;
-		localvars = NULL;
-		reffunc(cmdentry.u.func);
-		savehandler = handler;
-		if (setjmp(jmploc.loc)) {
-			popredir();
-			unreffunc(cmdentry.u.func);
-			poplocalvars();
-			localvars = savelocalvars;
-			freeparam(&shellparam);
-			shellparam = saveparam;
-			funcnest--;
-			handler = savehandler;
-			longjmp(handler->loc, 1);
-		}
-		handler = &jmploc;
-		funcnest++;
-		redirect(cmd->ncmd.redirect, REDIR_PUSH);
-		INTON;
-		for (i = 0; i < varlist.count; i++)
-			mklocal(varlist.args[i]);
-		exitstatus = oexitstatus;
-		evaltree(getfuncnode(cmdentry.u.func),
-		    flags & (EV_TESTED | EV_EXIT));
-		INTOFF;
-		unreffunc(cmdentry.u.func);
-		poplocalvars();
-		localvars = savelocalvars;
-		freeparam(&shellparam);
-		shellparam = saveparam;
-		handler = savehandler;
-		funcnest--;
-		popredir();
-		INTON;
-		if (evalskip == SKIPRETURN) {
-			evalskip = 0;
-			skipcount = 0;
-		}
-		if (jp)
-			exitshell(exitstatus);
-	} else if (cmdentry.cmdtype == CMDBUILTIN) {
-#ifdef DEBUG
-		trputs("builtin command:  ");  trargs(argv);
-#endif
-		mode = (cmdentry.u.index == EXECCMD)? 0 : REDIR_PUSH;
-		if (flags == EV_BACKCMD) {
-			memout.nextc = memout.buf;
-			mode |= REDIR_BACKQ;
-		}
-		savecmdname = commandname;
-		savetopfile = getcurrentfile();
-		cmdenviron = &varlist;
-		e = -1;
-		savehandler = handler;
-		if (setjmp(jmploc.loc)) {
-			e = exception;
-			if (e == EXINT)
-				exitstatus = SIGINT+128;
-			else if (e != EXEXIT)
-				exitstatus = 2;
-			goto cmddone;
-		}
-		handler = &jmploc;
-		redirect(cmd->ncmd.redirect, mode);
-		outclearerror(out1);
-		/*
-		 * If there is no command word, redirection errors should
-		 * not be fatal but assignment errors should.
-		 */
-		if (argc == 0)
-			cmdentry.special = 1;
-		listsetvar(cmdenviron, cmdentry.special ? 0 : VNOSET);
-		if (argc > 0)
-			bltinsetlocale();
-		commandname = argv[0];
-		argptr = argv + 1;
-		nextopt_optptr = NULL;		/* initialize nextopt */
-		builtin_flags = flags;
-		exitstatus = (*builtinfunc[cmdentry.u.index])(argc, argv);
-		flushall();
-		if (outiserror(out1)) {
-			warning("write error on stdout");
-			if (exitstatus == 0 || exitstatus == 1)
-				exitstatus = 2;
-		}
-cmddone:
-		if (argc > 0)
-			bltinunsetlocale();
-		cmdenviron = NULL;
-		out1 = &output;
-		out2 = &errout;
-		freestdout();
-		handler = savehandler;
-		commandname = savecmdname;
-		if (jp)
-			exitshell(exitstatus);
-		if (flags == EV_BACKCMD) {
-			backcmd->buf = memout.buf;
-			backcmd->nleft = memout.buf != NULL ?
-			    memout.nextc - memout.buf : 0;
-			memout.buf = NULL;
-			memout.nextc = NULL;
-			memout.bufend = NULL;
-			memout.bufsize = 64;
-		}
-		if (cmdentry.u.index != EXECCMD)
-			popredir();
-		if (e != -1) {
-			if ((e != EXERROR && e != EXEXEC)
-			    || cmdentry.special)
-				exraise(e);
-			popfilesupto(savetopfile);
-			if (flags != EV_BACKCMD)
-				FORCEINTON;
-		}
-	} else {
-#ifdef DEBUG
-		trputs("normal command:  ");  trargs(argv);
-#endif
-		redirect(cmd->ncmd.redirect, 0);
-		for (i = 0; i < varlist.count; i++)
-			setvareq(varlist.args[i], VEXPORT|VSTACK);
-		envp = environment();
-		shellexec(argv, envp, path, cmdentry.u.index);
-		/*NOTREACHED*/
-	}
-	goto out;
-
-parent:	/* parent process gets here (if we forked) */
-	if (mode == FORK_FG) {	/* argument to fork */
-		INTOFF;
-		exitstatus = waitforjob(jp, &signaled);
-		INTON;
-		if (iflag && loopnest > 0 && signaled) {
-			evalskip = SKIPBREAK;
-			skipcount = loopnest;
-		}
-	} else if (mode == FORK_NOJOB) {
-		backcmd->fd = pip[0];
-		close(pip[1]);
-		backcmd->jp = jp;
-	}
-
-out:
-	if (lastarg)
-		setvar("_", lastarg, 0);
-	if (do_clearcmdentry)
-		clearcmdentry();
-}
-
-
-
-/*
- * Search for a command.  This is called before we fork so that the
- * location of the command will be available in the parent as well as
- * the child.  The check for "goodname" is an overly conservative
- * check that the name will not be subject to expansion.
- */
-
-static void
-prehash(union node *n)
-{
-	struct cmdentry entry;
-
-	if (n && n->type == NCMD && n->ncmd.args)
-		if (goodname(n->ncmd.args->narg.text))
-			find_command(n->ncmd.args->narg.text, &entry, 0,
-				     pathval());
-}
-
-
-
-/*
- * Builtin commands.  Builtin commands whose functions are closely
- * tied to evaluation are implemented here.
- */
-
-/*
- * No command given, a bltin command with no arguments, or a bltin command
- * with an invalid name.
- */
-
-int
-bltincmd(int argc, char **argv)
-{
-	if (argc > 1) {
-		out2fmt_flush("%s: not found\n", argv[1]);
-		return 127;
-	}
-	/*
-	 * Preserve exitstatus of a previous possible command substitution
-	 * as POSIX mandates
-	 */
-	return exitstatus;
-}
-
-
-/*
- * Handle break and continue commands.  Break, continue, and return are
- * all handled by setting the evalskip flag.  The evaluation routines
- * above all check this flag, and if it is set they start skipping
- * commands rather than executing them.  The variable skipcount is
- * the number of loops to break/continue, or the number of function
- * levels to return.  (The latter is always 1.)  It should probably
- * be an error to break out of more loops than exist, but it isn't
- * in the standard shell so we don't make it one here.
- */
-
-int
-breakcmd(int argc, char **argv)
-{
-	long n;
-	char *end;
-
-	if (argc > 1) {
-		/* Allow arbitrarily large numbers. */
-		n = strtol(argv[1], &end, 10);
-		if (!is_digit(argv[1][0]) || *end != '\0')
-			error("Illegal number: %s", argv[1]);
-	} else
-		n = 1;
-	if (n > loopnest)
-		n = loopnest;
-	if (n > 0) {
-		evalskip = (**argv == 'c')? SKIPCONT : SKIPBREAK;
-		skipcount = n;
-	}
-	return 0;
-}
-
-/*
- * The `command' command.
- */
-int
-commandcmd(int argc __unused, char **argv __unused)
-{
-	const char *path;
-	int ch;
-	int cmd = -1;
-
-	path = bltinlookup("PATH", 1);
-
-	while ((ch = nextopt("pvV")) != '\0') {
-		switch (ch) {
-		case 'p':
-			path = _PATH_STDPATH;
-			break;
-		case 'v':
-			cmd = TYPECMD_SMALLV;
-			break;
-		case 'V':
-			cmd = TYPECMD_BIGV;
-			break;
-		}
-	}
-
-	if (cmd != -1) {
-		if (*argptr == NULL || argptr[1] != NULL)
-			error("wrong number of arguments");
-		return typecmd_impl(2, argptr - 1, cmd, path);
-	}
-	if (*argptr != NULL)
-		error("commandcmd bad call");
-
-	/*
-	 * Do nothing successfully if no command was specified;
-	 * ksh also does this.
-	 */
-	return 0;
-}
-
-
-/*
- * The return command.
- */
-
-int
-returncmd(int argc, char **argv)
-{
-	int ret = argc > 1 ? number(argv[1]) : oexitstatus;
-
-	evalskip = SKIPRETURN;
-	skipcount = 1;
-	return ret;
-}
-
-
-int
-falsecmd(int argc __unused, char **argv __unused)
-{
-	return 1;
-}
-
-
-int
-truecmd(int argc __unused, char **argv __unused)
-{
-	return 0;
-}
-
-
-int
-execcmd(int argc, char **argv)
-{
-	int i;
-
-	/*
-	 * Because we have historically not supported any options,
-	 * only treat "--" specially.
-	 */
-	if (argc > 1 && strcmp(argv[1], "--") == 0)
-		argc--, argv++;
-	if (argc > 1) {
-		iflag = 0;		/* exit on error */
-		mflag = 0;
-		optschanged();
-		for (i = 0; i < cmdenviron->count; i++)
-			setvareq(cmdenviron->args[i], VEXPORT|VSTACK);
-		shellexec(argv + 1, environment(), pathval(), 0);
-
-	}
-	return 0;
-}
-
-
-int
-timescmd(int argc __unused, char **argv __unused)
-{
-	struct rusage ru;
-	long shumins, shsmins, chumins, chsmins;
-	double shusecs, shssecs, chusecs, chssecs;
-
-	if (getrusage(RUSAGE_SELF, &ru) < 0)
-		return 1;
-	shumins = ru.ru_utime.tv_sec / 60;
-	shusecs = ru.ru_utime.tv_sec % 60 + ru.ru_utime.tv_usec / 1000000.;
-	shsmins = ru.ru_stime.tv_sec / 60;
-	shssecs = ru.ru_stime.tv_sec % 60 + ru.ru_stime.tv_usec / 1000000.;
-	if (getrusage(RUSAGE_CHILDREN, &ru) < 0)
-		return 1;
-	chumins = ru.ru_utime.tv_sec / 60;
-	chusecs = ru.ru_utime.tv_sec % 60 + ru.ru_utime.tv_usec / 1000000.;
-	chsmins = ru.ru_stime.tv_sec / 60;
-	chssecs = ru.ru_stime.tv_sec % 60 + ru.ru_stime.tv_usec / 1000000.;
-	out1fmt("%ldm%.3fs %ldm%.3fs\n%ldm%.3fs %ldm%.3fs\n", shumins,
-	    shusecs, shsmins, shssecs, chumins, chusecs, chsmins, chssecs);
-	return 0;
-}