Add mksh from CVS 2010/08/24 as system/core/mksh module

Both shells (ash from system/core/sh, and mksh) are built by
default but only the one where $(TARGET_SHELL) is set to is
actually installed (the shell and the mkshrc configuration
file are tagged shell_mksh for this to work).

Signed-off-by: Thorsten Glaser <tg@mirbsd.org>
diff --git a/mksh/src/syn.c b/mksh/src/syn.c
new file mode 100644
index 0000000..64b2867
--- /dev/null
+++ b/mksh/src/syn.c
@@ -0,0 +1,1004 @@
+/*	$OpenBSD: syn.c,v 1.28 2008/07/23 16:34:38 jaredy Exp $	*/
+
+/*-
+ * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ *	Thorsten Glaser <tg@mirbsd.org>
+ *
+ * Provided that these terms and disclaimer and all copyright notices
+ * are retained or reproduced in an accompanying document, permission
+ * is granted to deal in this work without restriction, including un-
+ * limited rights to use, publicly perform, distribute, sell, modify,
+ * merge, give away, or sublicence.
+ *
+ * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
+ * the utmost extent permitted by applicable law, neither express nor
+ * implied; without malicious intent or gross negligence. In no event
+ * may a licensor, author or contributor be held liable for indirect,
+ * direct, other damage, loss, or other issues arising in any way out
+ * of dealing in the work, even if advised of the possibility of such
+ * damage or existence of a defect, except proven that it results out
+ * of said person's immediate fault when using the work as intended.
+ */
+
+#include "sh.h"
+
+__RCSID("$MirOS: src/bin/mksh/syn.c,v 1.49 2010/07/17 22:09:39 tg Exp $");
+
+struct nesting_state {
+	int start_token;	/* token than began nesting (eg, FOR) */
+	int start_line;		/* line nesting began on */
+};
+
+static void yyparse(void);
+static struct op *pipeline(int);
+static struct op *andor(void);
+static struct op *c_list(int);
+static struct ioword *synio(int);
+static struct op *nested(int, int, int);
+static struct op *get_command(int);
+static struct op *dogroup(void);
+static struct op *thenpart(void);
+static struct op *elsepart(void);
+static struct op *caselist(void);
+static struct op *casepart(int);
+static struct op *function_body(char *, bool);
+static char **wordlist(void);
+static struct op *block(int, struct op *, struct op *, char **);
+static struct op *newtp(int);
+static void syntaxerr(const char *) MKSH_A_NORETURN;
+static void nesting_push(struct nesting_state *, int);
+static void nesting_pop(struct nesting_state *);
+static int assign_command(char *);
+static int inalias(struct source *);
+static Test_op dbtestp_isa(Test_env *, Test_meta);
+static const char *dbtestp_getopnd(Test_env *, Test_op, bool);
+static int dbtestp_eval(Test_env *, Test_op, const char *,
+    const char *, bool);
+static void dbtestp_error(Test_env *, int, const char *) MKSH_A_NORETURN;
+
+static struct op *outtree;		/* yyparse output */
+static struct nesting_state nesting;	/* \n changed to ; */
+
+static int reject;		/* token(cf) gets symbol again */
+static int symbol;		/* yylex value */
+
+#define REJECT		(reject = 1)
+#define ACCEPT		(reject = 0)
+#define token(cf)	((reject) ? (ACCEPT, symbol) : (symbol = yylex(cf)))
+#define tpeek(cf)	((reject) ? (symbol) : (REJECT, symbol = yylex(cf)))
+#define musthave(c,cf)	do { if (token(cf) != (c)) syntaxerr(NULL); } while (0)
+
+static void
+yyparse(void)
+{
+	int c;
+
+	ACCEPT;
+
+	outtree = c_list(source->type == SSTRING);
+	c = tpeek(0);
+	if (c == 0 && !outtree)
+		outtree = newtp(TEOF);
+	else if (c != '\n' && c != 0)
+		syntaxerr(NULL);
+}
+
+static struct op *
+pipeline(int cf)
+{
+	struct op *t, *p, *tl = NULL;
+
+	t = get_command(cf);
+	if (t != NULL) {
+		while (token(0) == '|') {
+			if ((p = get_command(CONTIN)) == NULL)
+				syntaxerr(NULL);
+			if (tl == NULL)
+				t = tl = block(TPIPE, t, p, NOWORDS);
+			else
+				tl = tl->right = block(TPIPE, tl->right, p, NOWORDS);
+		}
+		REJECT;
+	}
+	return (t);
+}
+
+static struct op *
+andor(void)
+{
+	struct op *t, *p;
+	int c;
+
+	t = pipeline(0);
+	if (t != NULL) {
+		while ((c = token(0)) == LOGAND || c == LOGOR) {
+			if ((p = pipeline(CONTIN)) == NULL)
+				syntaxerr(NULL);
+			t = block(c == LOGAND? TAND: TOR, t, p, NOWORDS);
+		}
+		REJECT;
+	}
+	return (t);
+}
+
+static struct op *
+c_list(int multi)
+{
+	struct op *t = NULL, *p, *tl = NULL;
+	int c, have_sep;
+
+	while (1) {
+		p = andor();
+		/* Token has always been read/rejected at this point, so
+		 * we don't worry about what flags to pass token()
+		 */
+		c = token(0);
+		have_sep = 1;
+		if (c == '\n' && (multi || inalias(source))) {
+			if (!p) /* ignore blank lines */
+				continue;
+		} else if (!p)
+			break;
+		else if (c == '&' || c == COPROC)
+			p = block(c == '&' ? TASYNC : TCOPROC,
+			    p, NOBLOCK, NOWORDS);
+		else if (c != ';')
+			have_sep = 0;
+		if (!t)
+			t = p;
+		else if (!tl)
+			t = tl = block(TLIST, t, p, NOWORDS);
+		else
+			tl = tl->right = block(TLIST, tl->right, p, NOWORDS);
+		if (!have_sep)
+			break;
+	}
+	REJECT;
+	return (t);
+}
+
+static struct ioword *
+synio(int cf)
+{
+	struct ioword *iop;
+	static struct ioword *nextiop = NULL;
+	bool ishere;
+
+	if (nextiop != NULL) {
+		iop = nextiop;
+		nextiop = NULL;
+		return (iop);
+	}
+
+	if (tpeek(cf) != REDIR)
+		return (NULL);
+	ACCEPT;
+	iop = yylval.iop;
+	ishere = (iop->flag&IOTYPE) == IOHERE;
+	musthave(LWORD, ishere ? HEREDELIM : 0);
+	if (ishere) {
+		iop->delim = yylval.cp;
+		if (*ident != 0) /* unquoted */
+			iop->flag |= IOEVAL;
+		if (herep > &heres[HERES - 1])
+			yyerror("too many <<s\n");
+		*herep++ = iop;
+	} else
+		iop->name = yylval.cp;
+
+	if (iop->flag & IOBASH) {
+		char *cp;
+
+		nextiop = alloc(sizeof(*iop), ATEMP);
+		nextiop->name = cp = alloc(5, ATEMP);
+
+		if (iop->unit > 9) {
+			*cp++ = CHAR;
+			*cp++ = '0' + (iop->unit / 10);
+		}
+		*cp++ = CHAR;
+		*cp++ = '0' + (iop->unit % 10);
+		*cp = EOS;
+
+		iop->flag &= ~IOBASH;
+		nextiop->unit = 2;
+		nextiop->flag = IODUP;
+		nextiop->delim = NULL;
+		nextiop->heredoc = NULL;
+	}
+	return (iop);
+}
+
+static struct op *
+nested(int type, int smark, int emark)
+{
+	struct op *t;
+	struct nesting_state old_nesting;
+
+	nesting_push(&old_nesting, smark);
+	t = c_list(true);
+	musthave(emark, KEYWORD|ALIAS);
+	nesting_pop(&old_nesting);
+	return (block(type, t, NOBLOCK, NOWORDS));
+}
+
+static struct op *
+get_command(int cf)
+{
+	struct op *t;
+	int c, iopn = 0, syniocf;
+	struct ioword *iop, **iops;
+	XPtrV args, vars;
+	struct nesting_state old_nesting;
+
+	iops = alloc((NUFILE + 1) * sizeof(struct ioword *), ATEMP);
+	XPinit(args, 16);
+	XPinit(vars, 16);
+
+	syniocf = KEYWORD|ALIAS;
+	switch (c = token(cf|KEYWORD|ALIAS|VARASN)) {
+	default:
+		REJECT;
+		afree(iops, ATEMP);
+		XPfree(args);
+		XPfree(vars);
+		return (NULL); /* empty line */
+
+	case LWORD:
+	case REDIR:
+		REJECT;
+		syniocf &= ~(KEYWORD|ALIAS);
+		t = newtp(TCOM);
+		t->lineno = source->line;
+		while (1) {
+			cf = (t->u.evalflags ? ARRAYVAR : 0) |
+			    (XPsize(args) == 0 ? ALIAS|VARASN : CMDWORD);
+			switch (tpeek(cf)) {
+			case REDIR:
+				while ((iop = synio(cf)) != NULL) {
+					if (iopn >= NUFILE)
+						yyerror("too many redirections\n");
+					iops[iopn++] = iop;
+				}
+				break;
+
+			case LWORD:
+				ACCEPT;
+				/* the iopn == 0 and XPsize(vars) == 0 are
+				 * dubious but AT&T ksh acts this way
+				 */
+				if (iopn == 0 && XPsize(vars) == 0 &&
+				    XPsize(args) == 0 &&
+				    assign_command(ident))
+					t->u.evalflags = DOVACHECK;
+				if ((XPsize(args) == 0 || Flag(FKEYWORD)) &&
+				    is_wdvarassign(yylval.cp))
+					XPput(vars, yylval.cp);
+				else
+					XPput(args, yylval.cp);
+				break;
+
+			case '(':
+				/* Check for "> foo (echo hi)" which AT&T ksh
+				 * allows (not POSIX, but not disallowed)
+				 */
+				afree(t, ATEMP);
+				if (XPsize(args) == 0 && XPsize(vars) == 0) {
+					ACCEPT;
+					goto Subshell;
+				}
+#ifndef MKSH_SMALL
+				if ((XPsize(args) == 0 || Flag(FKEYWORD)) &&
+				    XPsize(vars) == 1 && is_wdvarassign(yylval.cp))
+					goto is_wdarrassign;
+#endif
+				/* Must be a function */
+				if (iopn != 0 || XPsize(args) != 1 ||
+				    XPsize(vars) != 0)
+					syntaxerr(NULL);
+				ACCEPT;
+				/*(*/
+				musthave(')', 0);
+				t = function_body(XPptrv(args)[0], false);
+				goto Leave;
+#ifndef MKSH_SMALL
+ is_wdarrassign:
+			{
+				static const char set_cmd0[] = {
+					CHAR, 'e', CHAR, 'v',
+					CHAR, 'a', CHAR, 'l', EOS
+				};
+				static const char set_cmd1[] = {
+					CHAR, 's', CHAR, 'e',
+					CHAR, 't', CHAR, ' ',
+					CHAR, '-', CHAR, 'A', EOS
+				};
+				static const char set_cmd2[] = {
+					CHAR, '-', CHAR, '-', EOS
+				};
+				char *tcp;
+				XPfree(vars);
+				XPinit(vars, 16);
+				/*
+				 * we know (or rather hope) that yylval.cp
+				 * contains a string "varname="
+				 */
+				tcp = wdcopy(yylval.cp, ATEMP);
+				tcp[wdscan(tcp, EOS) - tcp - 3] = EOS;
+				/* now make an array assignment command */
+				t = newtp(TCOM);
+				t->lineno = source->line;
+				ACCEPT;
+				XPput(args, wdcopy(set_cmd0, ATEMP));
+				XPput(args, wdcopy(set_cmd1, ATEMP));
+				XPput(args, tcp);
+				XPput(args, wdcopy(set_cmd2, ATEMP));
+				musthave(LWORD,LETARRAY);
+				XPput(args, yylval.cp);
+				break;
+			}
+#endif
+
+			default:
+				goto Leave;
+			}
+		}
+ Leave:
+		break;
+
+	case '(':
+ Subshell:
+		t = nested(TPAREN, '(', ')');
+		break;
+
+	case '{': /*}*/
+		t = nested(TBRACE, '{', '}');
+		break;
+
+	case MDPAREN: {
+		int lno;
+		static const char let_cmd[] = {
+			CHAR, 'l', CHAR, 'e',
+			CHAR, 't', EOS
+		};
+
+		/* Leave KEYWORD in syniocf (allow if (( 1 )) then ...) */
+		lno = source->line;
+		ACCEPT;
+		switch (token(LETEXPR)) {
+		case LWORD:
+			break;
+		case '(':	/* ) */
+			goto Subshell;
+		default:
+			syntaxerr(NULL);
+		}
+		t = newtp(TCOM);
+		t->lineno = lno;
+		XPput(args, wdcopy(let_cmd, ATEMP));
+		XPput(args, yylval.cp);
+		break;
+	}
+
+	case DBRACKET: /* [[ .. ]] */
+		/* Leave KEYWORD in syniocf (allow if [[ -n 1 ]] then ...) */
+		t = newtp(TDBRACKET);
+		ACCEPT;
+		{
+			Test_env te;
+
+			te.flags = TEF_DBRACKET;
+			te.pos.av = &args;
+			te.isa = dbtestp_isa;
+			te.getopnd = dbtestp_getopnd;
+			te.eval = dbtestp_eval;
+			te.error = dbtestp_error;
+
+			test_parse(&te);
+		}
+		break;
+
+	case FOR:
+	case SELECT:
+		t = newtp((c == FOR) ? TFOR : TSELECT);
+		musthave(LWORD, ARRAYVAR);
+		if (!is_wdvarname(yylval.cp, true))
+			yyerror("%s: bad identifier\n",
+			    c == FOR ? "for" : "select");
+		strdupx(t->str, ident, ATEMP);
+		nesting_push(&old_nesting, c);
+		t->vars = wordlist();
+		t->left = dogroup();
+		nesting_pop(&old_nesting);
+		break;
+
+	case WHILE:
+	case UNTIL:
+		nesting_push(&old_nesting, c);
+		t = newtp((c == WHILE) ? TWHILE : TUNTIL);
+		t->left = c_list(true);
+		t->right = dogroup();
+		nesting_pop(&old_nesting);
+		break;
+
+	case CASE:
+		t = newtp(TCASE);
+		musthave(LWORD, 0);
+		t->str = yylval.cp;
+		nesting_push(&old_nesting, c);
+		t->left = caselist();
+		nesting_pop(&old_nesting);
+		break;
+
+	case IF:
+		nesting_push(&old_nesting, c);
+		t = newtp(TIF);
+		t->left = c_list(true);
+		t->right = thenpart();
+		musthave(FI, KEYWORD|ALIAS);
+		nesting_pop(&old_nesting);
+		break;
+
+	case BANG:
+		syniocf &= ~(KEYWORD|ALIAS);
+		t = pipeline(0);
+		if (t == NULL)
+			syntaxerr(NULL);
+		t = block(TBANG, NOBLOCK, t, NOWORDS);
+		break;
+
+	case TIME:
+		syniocf &= ~(KEYWORD|ALIAS);
+		t = pipeline(0);
+		if (t) {
+			t->str = alloc(2, ATEMP);
+			t->str[0] = '\0';	/* TF_* flags */
+			t->str[1] = '\0';
+		}
+		t = block(TTIME, t, NOBLOCK, NOWORDS);
+		break;
+
+	case FUNCTION:
+		musthave(LWORD, 0);
+		t = function_body(yylval.cp, true);
+		break;
+	}
+
+	while ((iop = synio(syniocf)) != NULL) {
+		if (iopn >= NUFILE)
+			yyerror("too many redirections\n");
+		iops[iopn++] = iop;
+	}
+
+	if (iopn == 0) {
+		afree(iops, ATEMP);
+		t->ioact = NULL;
+	} else {
+		iops[iopn++] = NULL;
+		iops = aresize(iops, iopn * sizeof(struct ioword *), ATEMP);
+		t->ioact = iops;
+	}
+
+	if (t->type == TCOM || t->type == TDBRACKET) {
+		XPput(args, NULL);
+		t->args = (const char **)XPclose(args);
+		XPput(vars, NULL);
+		t->vars = (char **) XPclose(vars);
+	} else {
+		XPfree(args);
+		XPfree(vars);
+	}
+
+	return (t);
+}
+
+static struct op *
+dogroup(void)
+{
+	int c;
+	struct op *list;
+
+	c = token(CONTIN|KEYWORD|ALIAS);
+	/* A {...} can be used instead of do...done for for/select loops
+	 * but not for while/until loops - we don't need to check if it
+	 * is a while loop because it would have been parsed as part of
+	 * the conditional command list...
+	 */
+	if (c == DO)
+		c = DONE;
+	else if (c == '{')
+		c = '}';
+	else
+		syntaxerr(NULL);
+	list = c_list(true);
+	musthave(c, KEYWORD|ALIAS);
+	return (list);
+}
+
+static struct op *
+thenpart(void)
+{
+	struct op *t;
+
+	musthave(THEN, KEYWORD|ALIAS);
+	t = newtp(0);
+	t->left = c_list(true);
+	if (t->left == NULL)
+		syntaxerr(NULL);
+	t->right = elsepart();
+	return (t);
+}
+
+static struct op *
+elsepart(void)
+{
+	struct op *t;
+
+	switch (token(KEYWORD|ALIAS|VARASN)) {
+	case ELSE:
+		if ((t = c_list(true)) == NULL)
+			syntaxerr(NULL);
+		return (t);
+
+	case ELIF:
+		t = newtp(TELIF);
+		t->left = c_list(true);
+		t->right = thenpart();
+		return (t);
+
+	default:
+		REJECT;
+	}
+	return (NULL);
+}
+
+static struct op *
+caselist(void)
+{
+	struct op *t, *tl;
+	int c;
+
+	c = token(CONTIN|KEYWORD|ALIAS);
+	/* A {...} can be used instead of in...esac for case statements */
+	if (c == IN)
+		c = ESAC;
+	else if (c == '{')
+		c = '}';
+	else
+		syntaxerr(NULL);
+	t = tl = NULL;
+	while ((tpeek(CONTIN|KEYWORD|ESACONLY)) != c) { /* no ALIAS here */
+		struct op *tc = casepart(c);
+		if (tl == NULL)
+			t = tl = tc, tl->right = NULL;
+		else
+			tl->right = tc, tl = tc;
+	}
+	musthave(c, KEYWORD|ALIAS);
+	return (t);
+}
+
+static struct op *
+casepart(int endtok)
+{
+	struct op *t;
+	XPtrV ptns;
+
+	XPinit(ptns, 16);
+	t = newtp(TPAT);
+	/* no ALIAS here */
+	if (token(CONTIN | KEYWORD) != '(')
+		REJECT;
+	do {
+		musthave(LWORD, 0);
+		XPput(ptns, yylval.cp);
+	} while (token(0) == '|');
+	REJECT;
+	XPput(ptns, NULL);
+	t->vars = (char **) XPclose(ptns);
+	musthave(')', 0);
+
+	t->left = c_list(true);
+	/* Note: POSIX requires the ;; */
+	if ((tpeek(CONTIN|KEYWORD|ALIAS)) != endtok)
+		musthave(BREAK, CONTIN|KEYWORD|ALIAS);
+	return (t);
+}
+
+static struct op *
+function_body(char *name,
+    bool ksh_func)		/* function foo { ... } vs foo() { .. } */
+{
+	char *sname, *p;
+	struct op *t;
+	bool old_func_parse;
+
+	sname = wdstrip(name, false, false);
+	/* Check for valid characters in name. POSIX and AT&T ksh93 say only
+	 * allow [a-zA-Z_0-9] but this allows more as old pdkshs have
+	 * allowed more (the following were never allowed:
+	 *	NUL TAB NL SP " $ & ' ( ) ; < = > \ ` |
+	 * C_QUOTE covers all but adds # * ? [ ]
+	 */
+	for (p = sname; *p; p++)
+		if (ctype(*p, C_QUOTE))
+			yyerror("%s: invalid function name\n", sname);
+
+	/* Note that POSIX allows only compound statements after foo(), sh and
+	 * AT&T ksh allow any command, go with the later since it shouldn't
+	 * break anything. However, for function foo, AT&T ksh only accepts
+	 * an open-brace.
+	 */
+	if (ksh_func) {
+		if (tpeek(CONTIN|KEYWORD|ALIAS) == '(' /* ) */) {
+			struct tbl *tp;
+
+			/* function foo () { */
+			ACCEPT;
+			musthave(')', 0);
+			/* degrade to POSIX function */
+			ksh_func = false;
+			if ((tp = ktsearch(&aliases, sname, hash(sname))))
+				ktdelete(tp);
+		}
+		musthave('{', CONTIN|KEYWORD|ALIAS); /* } */
+		REJECT;
+	}
+
+	t = newtp(TFUNCT);
+	t->str = sname;
+	t->u.ksh_func = ksh_func;
+	t->lineno = source->line;
+
+	old_func_parse = e->flags & EF_FUNC_PARSE;
+	e->flags |= EF_FUNC_PARSE;
+	if ((t->left = get_command(CONTIN)) == NULL) {
+		char *tv;
+		/*
+		 * Probably something like foo() followed by eof or ;.
+		 * This is accepted by sh and ksh88.
+		 * To make "typeset -f foo" work reliably (so its output can
+		 * be used as input), we pretend there is a colon here.
+		 */
+		t->left = newtp(TCOM);
+		t->left->args = alloc(2 * sizeof(char *), ATEMP);
+		t->left->args[0] = tv = alloc(3, ATEMP);
+		tv[0] = CHAR;
+		tv[1] = ':';
+		tv[2] = EOS;
+		t->left->args[1] = NULL;
+		t->left->vars = alloc(sizeof(char *), ATEMP);
+		t->left->vars[0] = NULL;
+		t->left->lineno = 1;
+	}
+	if (!old_func_parse)
+		e->flags &= ~EF_FUNC_PARSE;
+
+	return (t);
+}
+
+static char **
+wordlist(void)
+{
+	int c;
+	XPtrV args;
+
+	XPinit(args, 16);
+	/* POSIX does not do alias expansion here... */
+	if ((c = token(CONTIN|KEYWORD|ALIAS)) != IN) {
+		if (c != ';') /* non-POSIX, but AT&T ksh accepts a ; here */
+			REJECT;
+		return (NULL);
+	}
+	while ((c = token(0)) == LWORD)
+		XPput(args, yylval.cp);
+	if (c != '\n' && c != ';')
+		syntaxerr(NULL);
+	if (XPsize(args) == 0) {
+		XPfree(args);
+		return (NULL);
+	} else {
+		XPput(args, NULL);
+		return ((char **)XPclose(args));
+	}
+}
+
+/*
+ * supporting functions
+ */
+
+static struct op *
+block(int type, struct op *t1, struct op *t2, char **wp)
+{
+	struct op *t;
+
+	t = newtp(type);
+	t->left = t1;
+	t->right = t2;
+	t->vars = wp;
+	return (t);
+}
+
+const struct tokeninfo {
+	const char *name;
+	short val;
+	short reserved;
+} tokentab[] = {
+	/* Reserved words */
+	{ "if",		IF,	true },
+	{ "then",	THEN,	true },
+	{ "else",	ELSE,	true },
+	{ "elif",	ELIF,	true },
+	{ "fi",		FI,	true },
+	{ "case",	CASE,	true },
+	{ "esac",	ESAC,	true },
+	{ "for",	FOR,	true },
+	{ "select",	SELECT,	true },
+	{ "while",	WHILE,	true },
+	{ "until",	UNTIL,	true },
+	{ "do",		DO,	true },
+	{ "done",	DONE,	true },
+	{ "in",		IN,	true },
+	{ "function",	FUNCTION, true },
+	{ "time",	TIME,	true },
+	{ "{",		'{',	true },
+	{ "}",		'}',	true },
+	{ "!",		BANG,	true },
+	{ "[[",		DBRACKET, true },
+	/* Lexical tokens (0[EOF], LWORD and REDIR handled specially) */
+	{ "&&",		LOGAND,	false },
+	{ "||",		LOGOR,	false },
+	{ ";;",		BREAK,	false },
+	{ "((",		MDPAREN, false },
+	{ "|&",		COPROC,	false },
+	/* and some special cases... */
+	{ "newline",	'\n',	false },
+	{ NULL,		0,	false }
+};
+
+void
+initkeywords(void)
+{
+	struct tokeninfo const *tt;
+	struct tbl *p;
+
+	ktinit(&keywords, APERM,
+	    /* must be 80% of 2^n (currently 20 keywords) */ 32);
+	for (tt = tokentab; tt->name; tt++) {
+		if (tt->reserved) {
+			p = ktenter(&keywords, tt->name, hash(tt->name));
+			p->flag |= DEFINED|ISSET;
+			p->type = CKEYWD;
+			p->val.i = tt->val;
+		}
+	}
+}
+
+static void
+syntaxerr(const char *what)
+{
+	char redir[6];	/* 2<<- is the longest redirection, I think */
+	const char *s;
+	struct tokeninfo const *tt;
+	int c;
+
+	if (!what)
+		what = "unexpected";
+	REJECT;
+	c = token(0);
+ Again:
+	switch (c) {
+	case 0:
+		if (nesting.start_token) {
+			c = nesting.start_token;
+			source->errline = nesting.start_line;
+			what = "unmatched";
+			goto Again;
+		}
+		/* don't quote the EOF */
+		yyerror("%s: unexpected EOF\n", T_synerr);
+		/* NOTREACHED */
+
+	case LWORD:
+		s = snptreef(NULL, 32, "%S", yylval.cp);
+		break;
+
+	case REDIR:
+		s = snptreef(redir, sizeof(redir), "%R", yylval.iop);
+		break;
+
+	default:
+		for (tt = tokentab; tt->name; tt++)
+			if (tt->val == c)
+			    break;
+		if (tt->name)
+			s = tt->name;
+		else {
+			if (c > 0 && c < 256) {
+				redir[0] = c;
+				redir[1] = '\0';
+			} else
+				shf_snprintf(redir, sizeof(redir),
+					"?%d", c);
+			s = redir;
+		}
+	}
+	yyerror("%s: '%s' %s\n", T_synerr, s, what);
+}
+
+static void
+nesting_push(struct nesting_state *save, int tok)
+{
+	*save = nesting;
+	nesting.start_token = tok;
+	nesting.start_line = source->line;
+}
+
+static void
+nesting_pop(struct nesting_state *saved)
+{
+	nesting = *saved;
+}
+
+static struct op *
+newtp(int type)
+{
+	struct op *t;
+
+	t = alloc(sizeof(struct op), ATEMP);
+	t->type = type;
+	t->u.evalflags = 0;
+	t->args = NULL;
+	t->vars = NULL;
+	t->ioact = NULL;
+	t->left = t->right = NULL;
+	t->str = NULL;
+	return (t);
+}
+
+struct op *
+compile(Source *s)
+{
+	nesting.start_token = 0;
+	nesting.start_line = 0;
+	herep = heres;
+	source = s;
+	yyparse();
+	return (outtree);
+}
+
+/* This kludge exists to take care of sh/AT&T ksh oddity in which
+ * the arguments of alias/export/readonly/typeset have no field
+ * splitting, file globbing, or (normal) tilde expansion done.
+ * AT&T ksh seems to do something similar to this since
+ *	$ touch a=a; typeset a=[ab]; echo "$a"
+ *	a=[ab]
+ *	$ x=typeset; $x a=[ab]; echo "$a"
+ *	a=a
+ *	$
+ */
+static int
+assign_command(char *s)
+{
+	if (!*s)
+		return (0);
+	return ((strcmp(s, "alias") == 0) ||
+	    (strcmp(s, "export") == 0) ||
+	    (strcmp(s, "readonly") == 0) ||
+	    (strcmp(s, T_typeset) == 0));
+}
+
+/* Check if we are in the middle of reading an alias */
+static int
+inalias(struct source *s)
+{
+	for (; s && s->type == SALIAS; s = s->next)
+		if (!(s->flags & SF_ALIASEND))
+			return (1);
+	return (0);
+}
+
+
+/* Order important - indexed by Test_meta values
+ * Note that ||, &&, ( and ) can't appear in as unquoted strings
+ * in normal shell input, so these can be interpreted unambiguously
+ * in the evaluation pass.
+ */
+static const char dbtest_or[] = { CHAR, '|', CHAR, '|', EOS };
+static const char dbtest_and[] = { CHAR, '&', CHAR, '&', EOS };
+static const char dbtest_not[] = { CHAR, '!', EOS };
+static const char dbtest_oparen[] = { CHAR, '(', EOS };
+static const char dbtest_cparen[] = { CHAR, ')', EOS };
+const char *const dbtest_tokens[] = {
+	dbtest_or, dbtest_and, dbtest_not,
+	dbtest_oparen, dbtest_cparen
+};
+const char db_close[] = { CHAR, ']', CHAR, ']', EOS };
+const char db_lthan[] = { CHAR, '<', EOS };
+const char db_gthan[] = { CHAR, '>', EOS };
+
+/*
+ * Test if the current token is a whatever. Accepts the current token if
+ * it is. Returns 0 if it is not, non-zero if it is (in the case of
+ * TM_UNOP and TM_BINOP, the returned value is a Test_op).
+ */
+static Test_op
+dbtestp_isa(Test_env *te, Test_meta meta)
+{
+	int c = tpeek(ARRAYVAR | (meta == TM_BINOP ? 0 : CONTIN));
+	int uqword;
+	char *save = NULL;
+	Test_op ret = TO_NONOP;
+
+	/* unquoted word? */
+	uqword = c == LWORD && *ident;
+
+	if (meta == TM_OR)
+		ret = c == LOGOR ? TO_NONNULL : TO_NONOP;
+	else if (meta == TM_AND)
+		ret = c == LOGAND ? TO_NONNULL : TO_NONOP;
+	else if (meta == TM_NOT)
+		ret = (uqword && !strcmp(yylval.cp,
+		    dbtest_tokens[(int)TM_NOT])) ? TO_NONNULL : TO_NONOP;
+	else if (meta == TM_OPAREN)
+		ret = c == '(' /*)*/ ? TO_NONNULL : TO_NONOP;
+	else if (meta == TM_CPAREN)
+		ret = c == /*(*/ ')' ? TO_NONNULL : TO_NONOP;
+	else if (meta == TM_UNOP || meta == TM_BINOP) {
+		if (meta == TM_BINOP && c == REDIR &&
+		    (yylval.iop->flag == IOREAD || yylval.iop->flag == IOWRITE)) {
+			ret = TO_NONNULL;
+			save = wdcopy(yylval.iop->flag == IOREAD ?
+			    db_lthan : db_gthan, ATEMP);
+		} else if (uqword && (ret = test_isop(meta, ident)))
+			save = yylval.cp;
+	} else /* meta == TM_END */
+		ret = (uqword && !strcmp(yylval.cp,
+		    db_close)) ? TO_NONNULL : TO_NONOP;
+	if (ret != TO_NONOP) {
+		ACCEPT;
+		if (meta < NELEM(dbtest_tokens))
+			save = wdcopy(dbtest_tokens[(int)meta], ATEMP);
+		if (save)
+			XPput(*te->pos.av, save);
+	}
+	return (ret);
+}
+
+static const char *
+dbtestp_getopnd(Test_env *te, Test_op op MKSH_A_UNUSED,
+    bool do_eval MKSH_A_UNUSED)
+{
+	int c = tpeek(ARRAYVAR);
+
+	if (c != LWORD)
+		return (NULL);
+
+	ACCEPT;
+	XPput(*te->pos.av, yylval.cp);
+
+	return (null);
+}
+
+static int
+dbtestp_eval(Test_env *te MKSH_A_UNUSED, Test_op op MKSH_A_UNUSED,
+    const char *opnd1 MKSH_A_UNUSED, const char *opnd2 MKSH_A_UNUSED,
+    bool do_eval MKSH_A_UNUSED)
+{
+	return (1);
+}
+
+static void
+dbtestp_error(Test_env *te, int offset, const char *msg)
+{
+	te->flags |= TEF_ERROR;
+
+	if (offset < 0) {
+		REJECT;
+		/* Kludgy to say the least... */
+		symbol = LWORD;
+		yylval.cp = *(XPptrv(*te->pos.av) + XPsize(*te->pos.av) +
+		    offset);
+	}
+	syntaxerr(msg);
+}