1 files changed, 1677 insertions, 0 deletions

diff --git a/bin/dash/src/parser.c b/bin/dash/src/parser.c
new file mode 100644
index 00000000..499f7f8e
--- /dev/null
+++ b/bin/dash/src/parser.c
@@ -0,0 +1,1677 @@
+/*-
+ * Copyright (c) 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ * Copyright (c) 1997-2005
+ *	Herbert Xu <herbert@gondor.apana.org.au>.  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.
+ */
+
+#if HAVE_ALLOCA_H
+#include <alloca.h>
+#endif
+
+#include <stdlib.h>
+
+#include "shell.h"
+#include "parser.h"
+#include "nodes.h"
+#include "expand.h"	/* defines rmescapes() */
+#include "exec.h"	/* defines find_builtin() */
+#include "syntax.h"
+#include "options.h"
+#include "input.h"
+#include "output.h"
+#include "var.h"
+#include "error.h"
+#include "memalloc.h"
+#include "mystring.h"
+#include "alias.h"
+#include "show.h"
+#include "builtins.h"
+#include "system.h"
+#ifndef SMALL
+#include "myhistedit.h"
+#endif
+
+/*
+ * Shell command parser.
+ */
+
+/* values returned by readtoken */
+#include "token_vars.h"
+
+
+
+/* Used by expandstr to get here-doc like behaviour. */
+#define FAKEEOFMARK (char *)1
+
+
+
+struct heredoc {
+	struct heredoc *next;	/* next here document in list */
+	union node *here;		/* redirection node */
+	char *eofmark;		/* string indicating end of input */
+	int striptabs;		/* if set, strip leading tabs */
+};
+
+struct synstack {
+	const char *syntax;
+	struct synstack *prev;
+	struct synstack *next;
+	int innerdq;
+	int varpushed;
+	int dblquote;
+	int varnest;		/* levels of variables expansion */
+	int parenlevel;		/* levels of parens in arithmetic */
+	int dqvarnest;		/* levels of variables expansion within double quotes */
+};
+
+
+
+struct heredoc *heredoclist;	/* list of here documents to read */
+int doprompt;			/* if set, prompt the user */
+int needprompt;			/* true if interactive and at start of line */
+int lasttoken;			/* last token read */
+int tokpushback;		/* last token pushed back */
+char *wordtext;			/* text of last word returned by readtoken */
+int checkkwd;
+struct nodelist *backquotelist;
+union node *redirnode;
+struct heredoc *heredoc;
+int quoteflag;			/* set if (part of) last token was quoted */
+
+
+static char *promptcache;
+static char *rpromptcache;
+
+
+STATIC union node *list(int);
+STATIC union node *andor(void);
+STATIC union node *pipeline(void);
+STATIC union node *command(void);
+STATIC union node *simplecmd(void);
+STATIC union node *makename(void);
+STATIC void parsefname(void);
+STATIC void parseheredoc(void);
+STATIC int readtoken(void);
+STATIC int xxreadtoken(void);
+STATIC int pgetc_eatbnl();
+STATIC int readtoken1(int, char const *, char *, int);
+STATIC void synexpect(int) __attribute__((__noreturn__));
+STATIC void synerror(const char *) __attribute__((__noreturn__));
+STATIC void setprompt(int);
+
+
+int isassignment(const char *p)
+{
+	const char *q = endofname(p);
+	if (p == q)
+		return 0;
+	return *q == '=';
+}
+
+static inline int realeofmark(const char *eofmark)
+{
+	return eofmark && eofmark != FAKEEOFMARK;
+}
+
+
+/*
+ * Read and parse a command.  Returns NEOF on end of file.  (NULL is a
+ * valid parse tree indicating a blank line.)
+ */
+
+union node *
+parsecmd(int interact)
+{
+	tokpushback = 0;
+	checkkwd = 0;
+	heredoclist = 0;
+	doprompt = interact;
+	if (doprompt)
+		setprompt(doprompt);
+	needprompt = 0;
+	return list(1);
+}
+
+
+STATIC union node *
+list(int nlflag)
+{
+	int chknl = nlflag & 1 ? 0 : CHKNL;
+	union node *n1, *n2, *n3;
+	int tok;
+
+	n1 = NULL;
+	for (;;) {
+		checkkwd = chknl | CHKKWD | CHKALIAS;
+		tok = readtoken();
+		switch (tok) {
+		case TNL:
+			parseheredoc();
+			return n1;
+
+		case TEOF:
+			if (!n1 && !chknl)
+				n1 = NEOF;
+out_eof:
+			parseheredoc();
+			tokpushback++;
+			lasttoken = TEOF;
+			return n1;
+		}
+
+		tokpushback++;
+		if (nlflag == 2 && tokendlist[tok])
+			return n1;
+		nlflag |= 2;
+
+		n2 = andor();
+		tok = readtoken();
+		if (tok == TBACKGND) {
+			if (n2->type == NPIPE) {
+				n2->npipe.backgnd = 1;
+			} else {
+				if (n2->type != NREDIR) {
+					n3 = stalloc(sizeof(struct nredir));
+					n3->nredir.n = n2;
+					n3->nredir.redirect = NULL;
+					n2 = n3;
+				}
+				n2->type = NBACKGND;
+			}
+		}
+		if (n1 == NULL) {
+			n1 = n2;
+		}
+		else {
+			n3 = (union node *)stalloc(sizeof (struct nbinary));
+			n3->type = NSEMI;
+			n3->nbinary.ch1 = n1;
+			n3->nbinary.ch2 = n2;
+			n1 = n3;
+		}
+		switch (tok) {
+		case TEOF:
+			goto out_eof;
+		case TNL:
+			tokpushback++;
+			/* fall through */
+		case TBACKGND:
+		case TSEMI:
+			break;
+		default:
+			if (!chknl)
+				synexpect(-1);
+			tokpushback++;
+			return n1;
+		}
+	}
+}
+
+
+
+STATIC union node *
+andor(void)
+{
+	union node *n1, *n2, *n3;
+	int t;
+
+	n1 = pipeline();
+	for (;;) {
+		if ((t = readtoken()) == TAND) {
+			t = NAND;
+		} else if (t == TOR) {
+			t = NOR;
+		} else {
+			tokpushback++;
+			return n1;
+		}
+		checkkwd = CHKNL | CHKKWD | CHKALIAS;
+		n2 = pipeline();
+		n3 = (union node *)stalloc(sizeof (struct nbinary));
+		n3->type = t;
+		n3->nbinary.ch1 = n1;
+		n3->nbinary.ch2 = n2;
+		n1 = n3;
+	}
+}
+
+
+
+STATIC union node *
+pipeline(void)
+{
+	union node *n1, *n2, *pipenode;
+	struct nodelist *lp, *prev;
+	int negate;
+
+	negate = 0;
+	TRACE(("pipeline: entered\n"));
+	if (readtoken() == TNOT) {
+		negate = !negate;
+		checkkwd = CHKKWD | CHKALIAS;
+	} else
+		tokpushback++;
+	n1 = command();
+	if (readtoken() == TPIPE) {
+		pipenode = (union node *)stalloc(sizeof (struct npipe));
+		pipenode->type = NPIPE;
+		pipenode->npipe.backgnd = 0;
+		lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
+		pipenode->npipe.cmdlist = lp;
+		lp->n = n1;
+		do {
+			prev = lp;
+			lp = (struct nodelist *)stalloc(sizeof (struct nodelist));
+			checkkwd = CHKNL | CHKKWD | CHKALIAS;
+			lp->n = command();
+			prev->next = lp;
+		} while (readtoken() == TPIPE);
+		lp->next = NULL;
+		n1 = pipenode;
+	}
+	tokpushback++;
+	if (negate) {
+		n2 = (union node *)stalloc(sizeof (struct nnot));
+		n2->type = NNOT;
+		n2->nnot.com = n1;
+		return n2;
+	} else
+		return n1;
+}
+
+
+
+STATIC union node *
+command(void)
+{
+	union node *n1, *n2;
+	union node *ap, **app;
+	union node *cp, **cpp;
+	union node *redir, **rpp;
+	union node **rpp2;
+	int t;
+	int savelinno;
+
+	redir = NULL;
+	rpp2 = &redir;
+
+	savelinno = plinno;
+
+	switch (readtoken()) {
+	default:
+		synexpect(-1);
+		/* NOTREACHED */
+	case TIF:
+		n1 = (union node *)stalloc(sizeof (struct nif));
+		n1->type = NIF;
+		n1->nif.test = list(0);
+		if (readtoken() != TTHEN)
+			synexpect(TTHEN);
+		n1->nif.ifpart = list(0);
+		n2 = n1;
+		while (readtoken() == TELIF) {
+			n2->nif.elsepart = (union node *)stalloc(sizeof (struct nif));
+			n2 = n2->nif.elsepart;
+			n2->type = NIF;
+			n2->nif.test = list(0);
+			if (readtoken() != TTHEN)
+				synexpect(TTHEN);
+			n2->nif.ifpart = list(0);
+		}
+		if (lasttoken == TELSE)
+			n2->nif.elsepart = list(0);
+		else {
+			n2->nif.elsepart = NULL;
+			tokpushback++;
+		}
+		t = TFI;
+		break;
+	case TWHILE:
+	case TUNTIL: {
+		int got;
+		n1 = (union node *)stalloc(sizeof (struct nbinary));
+		n1->type = (lasttoken == TWHILE)? NWHILE : NUNTIL;
+		n1->nbinary.ch1 = list(0);
+		if ((got=readtoken()) != TDO) {
+TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : ""));
+			synexpect(TDO);
+		}
+		n1->nbinary.ch2 = list(0);
+		t = TDONE;
+		break;
+	}
+	case TFOR:
+		if (readtoken() != TWORD || quoteflag || ! goodname(wordtext))
+			synerror("Bad for loop variable");
+		n1 = (union node *)stalloc(sizeof (struct nfor));
+		n1->type = NFOR;
+		n1->nfor.linno = savelinno;
+		n1->nfor.var = wordtext;
+		checkkwd = CHKNL | CHKKWD | CHKALIAS;
+		if (readtoken() == TIN) {
+			app = &ap;
+			while (readtoken() == TWORD) {
+				n2 = (union node *)stalloc(sizeof (struct narg));
+				n2->type = NARG;
+				n2->narg.text = wordtext;
+				n2->narg.backquote = backquotelist;
+				*app = n2;
+				app = &n2->narg.next;
+			}
+			*app = NULL;
+			n1->nfor.args = ap;
+			if (lasttoken != TNL && lasttoken != TSEMI)
+				synexpect(-1);
+		} else {
+			n2 = (union node *)stalloc(sizeof (struct narg));
+			n2->type = NARG;
+			n2->narg.text = (char *)dolatstr;
+			n2->narg.backquote = NULL;
+			n2->narg.next = NULL;
+			n1->nfor.args = n2;
+			/*
+			 * Newline or semicolon here is optional (but note
+			 * that the original Bourne shell only allowed NL).
+			 */
+			if (lasttoken != TSEMI)
+				tokpushback++;
+		}
+		checkkwd = CHKNL | CHKKWD | CHKALIAS;
+		if (readtoken() != TDO)
+			synexpect(TDO);
+		n1->nfor.body = list(0);
+		t = TDONE;
+		break;
+	case TCASE:
+		n1 = (union node *)stalloc(sizeof (struct ncase));
+		n1->type = NCASE;
+		n1->ncase.linno = savelinno;
+		if (readtoken() != TWORD)
+			synexpect(TWORD);
+		n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg));
+		n2->type = NARG;
+		n2->narg.text = wordtext;
+		n2->narg.backquote = backquotelist;
+		n2->narg.next = NULL;
+		checkkwd = CHKNL | CHKKWD | CHKALIAS;
+		if (readtoken() != TIN)
+			synexpect(TIN);
+		cpp = &n1->ncase.cases;
+next_case:
+		checkkwd = CHKNL | CHKKWD;
+		t = readtoken();
+		while(t != TESAC) {
+			if (lasttoken == TLP)
+				readtoken();
+			*cpp = cp = (union node *)stalloc(sizeof (struct nclist));
+			cp->type = NCLIST;
+			app = &cp->nclist.pattern;
+			for (;;) {
+				*app = ap = (union node *)stalloc(sizeof (struct narg));
+				ap->type = NARG;
+				ap->narg.text = wordtext;
+				ap->narg.backquote = backquotelist;
+				if (readtoken() != TPIPE)
+					break;
+				app = &ap->narg.next;
+				readtoken();
+			}
+			ap->narg.next = NULL;
+			if (lasttoken != TRP)
+				synexpect(TRP);
+			cp->nclist.body = list(2);
+
+			cpp = &cp->nclist.next;
+
+			checkkwd = CHKNL | CHKKWD;
+			if ((t = readtoken()) != TESAC) {
+				if (t != TENDCASE)
+					synexpect(TENDCASE);
+				else
+					goto next_case;
+			}
+		}
+		*cpp = NULL;
+		goto redir;
+	case TLP:
+		n1 = (union node *)stalloc(sizeof (struct nredir));
+		n1->type = NSUBSHELL;
+		n1->nredir.linno = savelinno;
+		n1->nredir.n = list(0);
+		n1->nredir.redirect = NULL;
+		t = TRP;
+		break;
+	case TBEGIN:
+		n1 = list(0);
+		t = TEND;
+		break;
+	case TWORD:
+	case TREDIR:
+		tokpushback++;
+		return simplecmd();
+	}
+
+	if (readtoken() != t)
+		synexpect(t);
+
+redir:
+	/* Now check for redirection which may follow command */
+	checkkwd = CHKKWD | CHKALIAS;
+	rpp = rpp2;
+	while (readtoken() == TREDIR) {
+		*rpp = n2 = redirnode;
+		rpp = &n2->nfile.next;
+		parsefname();
+	}
+	tokpushback++;
+	*rpp = NULL;
+	if (redir) {
+		if (n1->type != NSUBSHELL) {
+			n2 = (union node *)stalloc(sizeof (struct nredir));
+			n2->type = NREDIR;
+			n2->nredir.linno = savelinno;
+			n2->nredir.n = n1;
+			n1 = n2;
+		}
+		n1->nredir.redirect = redir;
+	}
+
+	return n1;
+}
+
+
+STATIC union node *
+simplecmd(void) {
+	union node *args, **app;
+	union node *n = NULL;
+	union node *vars, **vpp;
+	union node **rpp, *redir;
+	int savecheckkwd;
+	int savelinno;
+
+	args = NULL;
+	app = &args;
+	vars = NULL;
+	vpp = &vars;
+	redir = NULL;
+	rpp = &redir;
+
+	savecheckkwd = CHKALIAS;
+	savelinno = plinno;
+	for (;;) {
+		checkkwd = savecheckkwd;
+		switch (readtoken()) {
+		case TWORD:
+			n = (union node *)stalloc(sizeof (struct narg));
+			n->type = NARG;
+			n->narg.text = wordtext;
+			n->narg.backquote = backquotelist;
+			if (savecheckkwd && isassignment(wordtext)) {
+				*vpp = n;
+				vpp = &n->narg.next;
+			} else {
+				*app = n;
+				app = &n->narg.next;
+				savecheckkwd = 0;
+			}
+			break;
+		case TREDIR:
+			*rpp = n = redirnode;
+			rpp = &n->nfile.next;
+			parsefname();	/* read name of redirection file */
+			break;
+		case TLP:
+			if (
+				args && app == &args->narg.next &&
+				!vars && !redir
+			) {
+				struct builtincmd *bcmd;
+				const char *name;
+
+				/* We have a function */
+				if (readtoken() != TRP)
+					synexpect(TRP);
+				name = n->narg.text;
+				if (
+					!goodname(name) || (
+						(bcmd = find_builtin(name)) &&
+						bcmd->flags & BUILTIN_SPECIAL
+					)
+				)
+					synerror("Bad function name");
+				n->type = NDEFUN;
+				checkkwd = CHKNL | CHKKWD | CHKALIAS;
+				n->ndefun.text = n->narg.text;
+				n->ndefun.linno = plinno;
+				n->ndefun.body = command();
+				return n;
+			}
+			/* fall through */
+		default:
+			tokpushback++;
+			goto out;
+		}
+	}
+out:
+	*app = NULL;
+	*vpp = NULL;
+	*rpp = NULL;
+	n = (union node *)stalloc(sizeof (struct ncmd));
+	n->type = NCMD;
+	n->ncmd.linno = savelinno;
+	n->ncmd.args = args;
+	n->ncmd.assign = vars;
+	n->ncmd.redirect = redir;
+	return n;
+}
+
+STATIC union node *
+makename(void)
+{
+	union node *n;
+
+	n = (union node *)stalloc(sizeof (struct narg));
+	n->type = NARG;
+	n->narg.next = NULL;
+	n->narg.text = wordtext;
+	n->narg.backquote = backquotelist;
+	return n;
+}
+
+void fixredir(union node *n, const char *text, int err)
+	{
+	TRACE(("Fix redir %s %d\n", text, err));
+	if (!err)
+		n->ndup.vname = NULL;
+
+	if (is_digit(text[0]) && text[1] == '\0')
+		n->ndup.dupfd = digit_val(text[0]);
+	else if (text[0] == '-' && text[1] == '\0')
+		n->ndup.dupfd = -1;
+	else {
+
+		if (err)
+			synerror("Bad fd number");
+		else
+			n->ndup.vname = makename();
+	}
+}
+
+
+STATIC void
+parsefname(void)
+{
+	union node *n = redirnode;
+
+	if (n->type == NHERE)
+		checkkwd = CHKEOFMARK;
+	if (readtoken() != TWORD)
+		synexpect(-1);
+	if (n->type == NHERE) {
+		struct heredoc *here = heredoc;
+		struct heredoc *p;
+
+		if (quoteflag == 0)
+			n->type = NXHERE;
+		TRACE(("Here document %d\n", n->type));
+		rmescapes(wordtext);
+		here->eofmark = wordtext;
+		here->next = NULL;
+		if (heredoclist == NULL)
+			heredoclist = here;
+		else {
+			for (p = heredoclist ; p->next ; p = p->next);
+			p->next = here;
+		}
+	} else if (n->type == NTOFD || n->type == NFROMFD) {
+		fixredir(n, wordtext, 0);
+	} else {
+		n->nfile.fname = makename();
+	}
+}
+
+
+/*
+ * Input any here documents.
+ */
+
+STATIC void
+parseheredoc(void)
+{
+	struct heredoc *here;
+	union node *n;
+
+	here = heredoclist;
+	heredoclist = 0;
+
+	while (here) {
+		if (needprompt) {
+			setprompt(2);
+		}
+		if (here->here->type == NHERE)
+			readtoken1(pgetc(), SQSYNTAX, here->eofmark, here->striptabs);
+		else
+			readtoken1(pgetc_eatbnl(), DQSYNTAX, here->eofmark, here->striptabs);
+		n = (union node *)stalloc(sizeof (struct narg));
+		n->narg.type = NARG;
+		n->narg.next = NULL;
+		n->narg.text = wordtext;
+		n->narg.backquote = backquotelist;
+		here->here->nhere.doc = n;
+		here = here->next;
+	}
+}
+
+STATIC int
+readtoken(void)
+{
+	int t;
+	int kwd = checkkwd;
+#ifdef DEBUG
+	int alreadyseen = tokpushback;
+#endif
+
+top:
+	t = xxreadtoken();
+
+	/*
+	 * eat newlines
+	 */
+	if (kwd & CHKNL) {
+		while (t == TNL) {
+			parseheredoc();
+			checkkwd = 0;
+			t = xxreadtoken();
+		}
+	}
+
+	kwd |= checkkwd;
+	checkkwd = 0;
+
+	if (t != TWORD || quoteflag) {
+		goto out;
+	}
+
+	/*
+	 * check for keywords
+	 */
+	if (kwd & CHKKWD) {
+		const char *const *pp;
+
+		if ((pp = findkwd(wordtext))) {
+			lasttoken = t = pp - parsekwd + KWDOFFSET;
+			TRACE(("keyword %s recognized\n", tokname[t]));
+			goto out;
+		}
+	}
+
+	if (kwd & CHKALIAS) {
+		struct alias *ap;
+		if ((ap = lookupalias(wordtext, 1)) != NULL) {
+			if (*ap->val) {
+				pushstring(ap->val, ap);
+			}
+			goto top;
+		}
+	}
+out:
+#ifdef DEBUG
+	if (!alreadyseen)
+	    TRACE(("token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
+	else
+	    TRACE(("reread token %s %s\n", tokname[t], t == TWORD ? wordtext : ""));
+#endif
+	return (t);
+}
+
+static void nlprompt(void)
+{
+	plinno++;
+	if (doprompt)
+		setprompt(2);
+}
+
+static void nlnoprompt(void)
+{
+	plinno++;
+	needprompt = doprompt;
+}
+
+
+/*
+ * Read the next input token.
+ * If the token is a word, we set backquotelist to the list of cmds in
+ *	backquotes.  We set quoteflag to true if any part of the word was
+ *	quoted.
+ * If the token is TREDIR, then we set redirnode to a structure containing
+ *	the redirection.
+ *
+ * [Change comment:  here documents and internal procedures]
+ * [Readtoken shouldn't have any arguments.  Perhaps we should make the
+ *  word parsing code into a separate routine.  In this case, readtoken
+ *  doesn't need to have any internal procedures, but parseword does.
+ *  We could also make parseoperator in essence the main routine, and
+ *  have parseword (readtoken1?) handle both words and redirection.]
+ */
+
+#define RETURN(token)	return lasttoken = token
+
+STATIC int
+xxreadtoken(void)
+{
+	int c;
+
+	if (tokpushback) {
+		tokpushback = 0;
+		return lasttoken;
+	}
+	if (needprompt) {
+		setprompt(2);
+	}
+	for (;;) {	/* until token or start of word found */
+		c = pgetc_eatbnl();
+		switch (c) {
+		case ' ': case '\t':
+		case PEOA:
+			continue;
+		case '#':
+			while ((c = pgetc()) != '\n' && c != PEOF);
+			pungetc();
+			continue;
+		case '\n':
+			nlnoprompt();
+			RETURN(TNL);
+		case PEOF:
+			RETURN(TEOF);
+		case '&':
+			if (pgetc_eatbnl() == '&')
+				RETURN(TAND);
+			pungetc();
+			RETURN(TBACKGND);
+		case '|':
+			if (pgetc_eatbnl() == '|')
+				RETURN(TOR);
+			pungetc();
+			RETURN(TPIPE);
+		case ';':
+			if (pgetc_eatbnl() == ';')
+				RETURN(TENDCASE);
+			pungetc();
+			RETURN(TSEMI);
+		case '(':
+			RETURN(TLP);
+		case ')':
+			RETURN(TRP);
+		}
+		break;
+	}
+	return readtoken1(c, BASESYNTAX, (char *)NULL, 0);
+#undef RETURN
+}
+
+static int pgetc_eatbnl(void)
+{
+	int c;
+
+	while ((c = pgetc()) == '\\') {
+		if (pgetc2() != '\n') {
+			pungetc();
+			break;
+		}
+
+		nlprompt();
+	}
+
+	return c;
+}
+
+static int pgetc_top(struct synstack *stack)
+{
+	return stack->syntax == SQSYNTAX ? pgetc() : pgetc_eatbnl();
+}
+
+static void synstack_push(struct synstack **stack, struct synstack *next,
+			  const char *syntax)
+{
+	memset(next, 0, sizeof(*next));
+	next->syntax = syntax;
+	next->next = *stack;
+	(*stack)->prev = next;
+	*stack = next;
+}
+
+static void synstack_pop(struct synstack **stack)
+{
+	*stack = (*stack)->next;
+}
+
+
+
+/*
+ * If eofmark is NULL, read a word or a redirection symbol.  If eofmark
+ * is not NULL, read a here document.  In the latter case, eofmark is the
+ * word which marks the end of the document and striptabs is true if
+ * leading tabs should be stripped from the document.  The argument firstc
+ * is the first character of the input token or document.
+ *
+ * Because C does not have internal subroutines, I have simulated them
+ * using goto's to implement the subroutine linkage.  The following macros
+ * will run code that appears at the end of readtoken1.
+ */
+
+#define CHECKEND()	{goto checkend; checkend_return:;}
+#define PARSEREDIR()	{goto parseredir; parseredir_return:;}
+#define PARSESUB()	{goto parsesub; parsesub_return:;}
+#define PARSEBACKQOLD()	{oldstyle = 1; goto parsebackq; parsebackq_oldreturn:;}
+#define PARSEBACKQNEW()	{oldstyle = 0; goto parsebackq; parsebackq_newreturn:;}
+#define	PARSEARITH()	{goto parsearith; parsearith_return:;}
+
+STATIC int
+readtoken1(int firstc, char const *syntax, char *eofmark, int striptabs)
+{
+	int c = firstc;
+	char *out;
+	size_t len;
+	struct nodelist *bqlist;
+	int quotef;
+	int oldstyle;
+	/* syntax stack */
+	struct synstack synbase = { .syntax = syntax };
+	struct synstack *synstack = &synbase;
+
+	if (syntax == DQSYNTAX)
+		synstack->dblquote = 1;
+	quotef = 0;
+	bqlist = NULL;
+
+	STARTSTACKSTR(out);
+	loop: {	/* for each line, until end of word */
+#if ATTY
+		if (c == '\034' && doprompt
+		 && attyset() && ! equal(termval(), "emacs")) {
+			attyline();
+			if (synstack->syntax == BASESYNTAX)
+				return readtoken();
+			c = pgetc_top(synstack);
+			goto loop;
+		}
+#endif
+		CHECKEND();	/* set c to PEOF if at end of here document */
+		for (;;) {	/* until end of line or end of word */
+			CHECKSTRSPACE(4, out);	/* permit 4 calls to USTPUTC */
+			switch(synstack->syntax[c]) {
+			case CNL:	/* '\n' */
+				if (synstack->syntax == BASESYNTAX &&
+				    !synstack->varnest)
+					goto endword;	/* exit outer loop */
+				USTPUTC(c, out);
+				nlprompt();
+				c = pgetc_top(synstack);
+				goto loop;		/* continue outer loop */
+			case CWORD:
+				USTPUTC(c, out);
+				break;
+			case CCTL:
+				if ((!eofmark) | synstack->dblquote |
+				    synstack->varnest)
+					USTPUTC(CTLESC, out);
+				USTPUTC(c, out);
+				break;
+			/* backslash */
+			case CBACK:
+				c = pgetc2();
+				if (c == PEOF) {
+					USTPUTC(CTLESC, out);
+					USTPUTC('\\', out);
+					pungetc();
+				} else {
+					if (
+						synstack->dblquote &&
+						c != '\\' && c != '`' &&
+						c != '$' && (
+							c != '"' ||
+							(eofmark != NULL &&
+							 !synstack->varnest)
+						) && (
+							c != '}' ||
+							!synstack->varnest
+						)
+					) {
+						USTPUTC(CTLESC, out);
+						USTPUTC('\\', out);
+					}
+					USTPUTC(CTLESC, out);
+					USTPUTC(c, out);
+					quotef++;
+				}
+				break;
+			case CSQUOTE:
+				synstack->syntax = SQSYNTAX;
+quotemark:
+				if (eofmark == NULL) {
+					USTPUTC(CTLQUOTEMARK, out);
+				}
+				break;
+			case CDQUOTE:
+				synstack->syntax = DQSYNTAX;
+				synstack->dblquote = 1;
+toggledq:
+				if (synstack->varnest)
+					synstack->innerdq ^= 1;
+				goto quotemark;
+			case CENDQUOTE:
+				if (eofmark && !synstack->varnest) {
+					USTPUTC(c, out);
+					break;
+				}
+
+				if (synstack->dqvarnest == 0) {
+					synstack->syntax = BASESYNTAX;
+					synstack->dblquote = 0;
+				}
+
+				quotef++;
+
+				if (c == '"')
+					goto toggledq;
+
+				goto quotemark;
+			case CVAR:	/* '$' */
+				PARSESUB();		/* parse substitution */
+				break;
+			case CENDVAR:	/* '}' */
+				if (!synstack->innerdq &&
+				    synstack->varnest > 0) {
+					if (!--synstack->varnest &&
+					    synstack->varpushed)
+						synstack_pop(&synstack);
+					else if (synstack->dqvarnest > 0)
+						synstack->dqvarnest--;
+					USTPUTC(CTLENDVAR, out);
+				} else {
+					USTPUTC(c, out);
+				}
+				break;
+			case CLP:	/* '(' in arithmetic */
+				synstack->parenlevel++;
+				USTPUTC(c, out);
+				break;
+			case CRP:	/* ')' in arithmetic */
+				if (synstack->parenlevel > 0) {
+					USTPUTC(c, out);
+					--synstack->parenlevel;
+				} else {
+					if (pgetc_eatbnl() == ')') {
+						USTPUTC(CTLENDARI, out);
+						synstack_pop(&synstack);
+					} else {
+						/*
+						 * unbalanced parens
+						 *  (don't 2nd guess - no error)
+						 */
+						pungetc();
+						USTPUTC(')', out);
+					}
+				}
+				break;
+			case CBQUOTE:	/* '`' */
+				if (checkkwd & CHKEOFMARK) {
+					USTPUTC('`', out);
+					break;
+				}
+
+				PARSEBACKQOLD();
+				break;
+			case CEOF:
+				goto endword;		/* exit outer loop */
+			case CIGN:
+				break;
+			default:
+				if (synstack->varnest == 0)
+					goto endword;	/* exit outer loop */
+				if (c != PEOA) {
+					USTPUTC(c, out);
+				}
+			}
+			c = pgetc_top(synstack);
+		}
+	}
+endword:
+	if (synstack->syntax == ARISYNTAX)
+		synerror("Missing '))'");
+	if (synstack->syntax != BASESYNTAX && eofmark == NULL)
+		synerror("Unterminated quoted string");
+	if (synstack->varnest != 0) {
+		/* { */
+		synerror("Missing '}'");
+	}
+	USTPUTC('\0', out);
+	len = out - (char *)stackblock();
+	out = stackblock();
+	if (eofmark == NULL) {
+		if ((c == '>' || c == '<')
+		 && quotef == 0
+		 && len <= 2
+		 && (*out == '\0' || is_digit(*out))) {
+			PARSEREDIR();
+			return lasttoken = TREDIR;
+		} else {
+			pungetc();
+		}
+	}
+	quoteflag = quotef;
+	backquotelist = bqlist;
+	grabstackblock(len);
+	wordtext = out;
+	return lasttoken = TWORD;
+/* end of readtoken routine */
+
+
+
+/*
+ * Check to see whether we are at the end of the here document.  When this
+ * is called, c is set to the first character of the next input line.  If
+ * we are at the end of the here document, this routine sets the c to PEOF.
+ */
+
+checkend: {
+	if (realeofmark(eofmark)) {
+		int markloc;
+		char *p;
+
+		if (c == PEOA) {
+			c = pgetc2();
+		}
+		if (striptabs) {
+			while (c == '\t') {
+				c = pgetc2();
+			}
+		}
+
+		markloc = out - (char *)stackblock();
+		for (p = eofmark; STPUTC(c, out), *p; p++) {
+			if (c != *p)
+				goto more_heredoc;
+
+			c = pgetc2();
+		}
+
+		if (c == '\n' || c == PEOF) {
+			c = PEOF;
+			nlnoprompt();
+		} else {
+			int len;
+
+more_heredoc:
+			p = (char *)stackblock() + markloc + 1;
+			len = out - p;
+
+			if (len) {
+				len -= c < 0;
+				c = p[-1];
+
+				if (len) {
+					char *str;
+
+					str = alloca(len + 1);
+					*(char *)mempcpy(str, p, len) = 0;
+
+					pushstring(str, NULL);
+				}
+			}
+		}
+
+		STADJUST((char *)stackblock() + markloc - out, out);
+	}
+	goto checkend_return;
+}
+
+
+/*
+ * Parse a redirection operator.  The variable "out" points to a string
+ * specifying the fd to be redirected.  The variable "c" contains the
+ * first character of the redirection operator.
+ */
+
+parseredir: {
+	char fd = *out;
+	union node *np;
+
+	np = (union node *)stalloc(sizeof (struct nfile));
+	if (c == '>') {
+		np->nfile.fd = 1;
+		c = pgetc_eatbnl();
+		if (c == '>')
+			np->type = NAPPEND;
+		else if (c == '|')
+			np->type = NCLOBBER;
+		else if (c == '&')
+			np->type = NTOFD;
+		else {
+			np->type = NTO;
+			pungetc();
+		}
+	} else {	/* c == '<' */
+		np->nfile.fd = 0;
+		switch (c = pgetc_eatbnl()) {
+		case '<':
+			if (sizeof (struct nfile) != sizeof (struct nhere)) {
+				np = (union node *)stalloc(sizeof (struct nhere));
+				np->nfile.fd = 0;
+			}
+			np->type = NHERE;
+			heredoc = (struct heredoc *)stalloc(sizeof (struct heredoc));
+			heredoc->here = np;
+			if ((c = pgetc_eatbnl()) == '-') {
+				heredoc->striptabs = 1;
+			} else {
+				heredoc->striptabs = 0;
+				pungetc();
+			}
+			break;
+
+		case '&':
+			np->type = NFROMFD;
+			break;
+
+		case '>':
+			np->type = NFROMTO;
+			break;
+
+		default:
+			np->type = NFROM;
+			pungetc();
+			break;
+		}
+	}
+	if (fd != '\0')
+		np->nfile.fd = digit_val(fd);
+	redirnode = np;
+	goto parseredir_return;
+}
+
+
+/*
+ * Parse a substitution.  At this point, we have read the dollar sign
+ * and nothing else.
+ */
+
+parsesub: {
+	int subtype;
+	int typeloc;
+	char *p;
+	static const char types[] = "}-+?=";
+
+	c = pgetc_eatbnl();
+	if (
+		(checkkwd & CHKEOFMARK) ||
+		c <= PEOA  ||
+		(c != '(' && c != '{' && !is_name(c) && !is_special(c))
+	) {
+		USTPUTC('$', out);
+		pungetc();
+	} else if (c == '(') {	/* $(command) or $((arith)) */
+		if (pgetc_eatbnl() == '(') {
+			PARSEARITH();
+		} else {
+			pungetc();
+			PARSEBACKQNEW();
+		}
+	} else {
+		const char *newsyn = synstack->syntax;
+
+		USTPUTC(CTLVAR, out);
+		typeloc = out - (char *)stackblock();
+		STADJUST(1, out);
+		subtype = VSNORMAL;
+		if (likely(c == '{')) {
+			c = pgetc_eatbnl();
+			subtype = 0;
+		}
+varname:
+		if (is_name(c)) {
+			do {
+				STPUTC(c, out);
+				c = pgetc_eatbnl();
+			} while (is_in_name(c));
+		} else if (is_digit(c)) {
+			do {
+				STPUTC(c, out);
+				c = pgetc_eatbnl();
+			} while (!subtype && is_digit(c));
+		} else if (c != '}') {
+			int cc = c;
+
+			c = pgetc_eatbnl();
+
+			if (!subtype && cc == '#') {
+				subtype = VSLENGTH;
+
+				if (c == '_' || isalnum(c))
+					goto varname;
+
+				cc = c;
+				c = pgetc_eatbnl();
+				if (cc == '}' || c != '}') {
+					pungetc();
+					subtype = 0;
+					c = cc;
+					cc = '#';
+				}
+			}
+
+			if (!is_special(cc)) {
+				if (subtype == VSLENGTH)
+					subtype = 0;
+				goto badsub;
+			}
+
+			USTPUTC(cc, out);
+		} else
+			goto badsub;
+
+		if (subtype == 0) {
+			int cc = c;
+
+			switch (c) {
+			case ':':
+				subtype = VSNUL;
+				c = pgetc_eatbnl();
+				/*FALLTHROUGH*/
+			default:
+				p = strchr(types, c);
+				if (p == NULL)
+					break;
+				subtype |= p - types + VSNORMAL;
+				break;
+			case '%':
+			case '#':
+				subtype = c == '#' ? VSTRIMLEFT :
+						     VSTRIMRIGHT;
+				c = pgetc_eatbnl();
+				if (c == cc)
+					subtype++;
+				else
+					pungetc();
+
+				newsyn = BASESYNTAX;
+				break;
+			}
+		} else {
+badsub:
+			pungetc();
+		}
+
+		if (newsyn == ARISYNTAX)
+			newsyn = DQSYNTAX;
+
+		if ((newsyn != synstack->syntax || synstack->innerdq) &&
+		    subtype != VSNORMAL) {
+			synstack_push(&synstack,
+				      synstack->prev ?:
+				      alloca(sizeof(*synstack)),
+				      newsyn);
+
+			synstack->varpushed++;
+			synstack->dblquote = newsyn != BASESYNTAX;
+		}
+
+		*((char *)stackblock() + typeloc) = subtype;
+		if (subtype != VSNORMAL) {
+			synstack->varnest++;
+			if (synstack->dblquote)
+				synstack->dqvarnest++;
+		}
+		STPUTC('=', out);
+	}
+	goto parsesub_return;
+}
+
+
+/*
+ * Called to parse command substitutions.  Newstyle is set if the command
+ * is enclosed inside $(...); nlpp is a pointer to the head of the linked
+ * list of commands (passed by reference), and savelen is the number of
+ * characters on the top of the stack which must be preserved.
+ */
+
+parsebackq: {
+	struct nodelist **nlpp;
+	union node *n;
+	char *str;
+	size_t savelen;
+	struct heredoc *saveheredoclist;
+	int uninitialized_var(saveprompt);
+
+	str = NULL;
+	savelen = out - (char *)stackblock();
+	if (savelen > 0) {
+		str = alloca(savelen);
+		memcpy(str, stackblock(), savelen);
+	}
+        if (oldstyle) {
+                /* We must read until the closing backquote, giving special
+                   treatment to some slashes, and then push the string and
+                   reread it as input, interpreting it normally.  */
+                char *pout;
+                int pc;
+                size_t psavelen;
+                char *pstr;
+
+
+                STARTSTACKSTR(pout);
+		for (;;) {
+			if (needprompt) {
+				setprompt(2);
+			}
+			switch (pc = pgetc_eatbnl()) {
+			case '`':
+				goto done;
+
+			case '\\':
+                                pc = pgetc();
+                                if (pc != '\\' && pc != '`' && pc != '$'
+                                    && (!synstack->dblquote || pc != '"'))
+                                        STPUTC('\\', pout);
+				if (pc > PEOA) {
+					break;
+				}
+				/* fall through */
+
+			case PEOF:
+			case PEOA:
+				synerror("EOF in backquote substitution");
+
+			case '\n':
+				nlnoprompt();
+				break;
+
+			default:
+				break;
+			}
+			STPUTC(pc, pout);
+                }
+done:
+                STPUTC('\0', pout);
+                psavelen = pout - (char *)stackblock();
+                if (psavelen > 0) {
+			pstr = grabstackstr(pout);
+			setinputstring(pstr);
+                }
+        }
+	nlpp = &bqlist;
+	while (*nlpp)
+		nlpp = &(*nlpp)->next;
+	*nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist));
+	(*nlpp)->next = NULL;
+
+	saveheredoclist = heredoclist;
+	heredoclist = NULL;
+
+	if (oldstyle) {
+		saveprompt = doprompt;
+		doprompt = 0;
+	}
+
+	n = list(2);
+
+	if (oldstyle)
+		doprompt = saveprompt;
+	else {
+		if (readtoken() != TRP)
+			synexpect(TRP);
+		setinputstring(nullstr);
+	}
+
+	parseheredoc();
+	heredoclist = saveheredoclist;
+
+	(*nlpp)->n = n;
+	/* Start reading from old file again. */
+	popfile();
+	/* Ignore any pushed back tokens left from the backquote parsing. */
+	if (oldstyle)
+		tokpushback = 0;
+	out = growstackto(savelen + 1);
+	if (str) {
+		memcpy(out, str, savelen);
+		STADJUST(savelen, out);
+	}
+	USTPUTC(CTLBACKQ, out);
+	if (oldstyle)
+		goto parsebackq_oldreturn;
+	else
+		goto parsebackq_newreturn;
+}
+
+/*
+ * Parse an arithmetic expansion (indicate start of one and set state)
+ */
+parsearith: {
+
+	synstack_push(&synstack,
+		      synstack->prev ?: alloca(sizeof(*synstack)),
+		      ARISYNTAX);
+	synstack->dblquote = 1;
+	USTPUTC(CTLARI, out);
+	goto parsearith_return;
+}
+
+} /* end of readtoken */
+
+
+
+#ifdef mkinit
+INCLUDE "parser.h"
+#endif
+
+
+/*
+ * Return of a legal variable name (a letter or underscore followed by zero or
+ * more letters, underscores, and digits).
+ */
+
+char *
+endofname(const char *name)
+	{
+	char *p;
+
+	p = (char *) name;
+	if (! is_name(*p))
+		return p;
+	while (*++p) {
+		if (! is_in_name(*p))
+			break;
+	}
+	return p;
+}
+
+
+/*
+ * Called when an unexpected token is read during the parse.  The argument
+ * is the token that is expected, or -1 if more than one type of token can
+ * occur at this point.
+ */
+
+STATIC void
+synexpect(int token)
+{
+	char msg[64];
+
+	if (token >= 0) {
+		fmtstr(msg, 64, "%s unexpected (expecting %s)",
+			tokname[lasttoken], tokname[token]);
+	} else {
+		fmtstr(msg, 64, "%s unexpected", tokname[lasttoken]);
+	}
+	synerror(msg);
+	/* NOTREACHED */
+}
+
+
+STATIC void
+synerror(const char *msg)
+{
+	errlinno = plinno;
+	sh_error("Syntax error: %s", msg);
+	/* NOTREACHED */
+}
+
+const char *
+expandstr(const char *ps)
+{
+	struct parsefile *file_stop;
+	struct jmploc *volatile savehandler;
+	struct heredoc *saveheredoclist;
+	const char *result;
+	int saveprompt;
+	struct jmploc jmploc;
+	union node n;
+	int err;
+
+	file_stop = parsefile;
+
+	/* XXX Fix (char *) cast. */
+	setinputstring((char *)ps);
+
+	saveheredoclist = heredoclist;
+	heredoclist = NULL;
+	saveprompt = doprompt;
+	doprompt = 0;
+	result = ps;
+	savehandler = handler;
+	if (unlikely(err = setjmp(jmploc.loc)))
+		goto out;
+	handler = &jmploc;
+
+	readtoken1(pgetc_eatbnl(), DQSYNTAX, FAKEEOFMARK, 0);
+
+	n.narg.type = NARG;
+	n.narg.next = NULL;
+	n.narg.text = wordtext;
+	n.narg.backquote = backquotelist;
+
+	expandarg(&n, NULL, EXP_QUOTED);
+	result = stackblock();
+
+out:
+	handler = savehandler;
+	if (err && exception != EXERROR)
+		longjmp(handler->loc, 1);
+
+	doprompt = saveprompt;
+	unwindfiles(file_stop);
+	heredoclist = saveheredoclist;
+
+	return result;
+}
+
+STATIC void
+setprompt(int which)
+{
+	struct stackmark smark;
+	const char *prompt, *rprompt, *nl;
+	int show;
+
+	needprompt = 0;
+	whichprompt = which;
+
+	switch (whichprompt) {
+	default:
+#ifdef DEBUG
+		prompt = "<internal prompt error>";
+		rprompt = prompt;
+		break;
+#endif
+	case 0:
+		prompt = nullstr;
+		rprompt = nullstr;
+		break;
+	case 1:
+		prompt = ps1val();
+		rprompt = rps1val();
+		break;
+	case 2:
+		prompt = ps2val();
+		rprompt = rps2val();
+		break;
+	}
+
+#ifdef SMALL
+	show = 1;
+#else
+	show = !el;
+#endif
+	pushstackmark(&smark, stackblocksize());
+	if (show) {
+		out2str(expandstr(prompt));
+	} else {
+		free(promptcache);
+		free(rpromptcache);
+		promptcache = savestr(expandstr(prompt));
+		rpromptcache = savestr(expandstr(rprompt));
+
+		nl = strrchr(promptcache, '\n');
+		if (nl)
+			outmem(promptcache, &nl[1] - promptcache, out2);
+	}
+	popstackmark(&smark);
+}
+
+/*
+ * called by editline -- return the cached prompt expansion.
+ */
+const char *
+getprompt(void *unused)
+{
+	const char *nl;
+
+	nl = strrchr(promptcache, '\n');
+
+	if (nl)
+		return &nl[1];
+	else
+		return promptcache;
+}
+
+const char *
+getrprompt(void *unused)
+{
+	return rpromptcache;
+}
+
+const char *const *
+findkwd(const char *s)
+{
+	return findstring(
+		s, parsekwd, sizeof(parsekwd) / sizeof(const char *)
+	);
+}