be more robust against things like Debian #535970

reverts and rewrites the code from cid 10047C1EBA57E4F4AF0

XXX find out if this is done right

check.t

@@ -1,4 +1,4 @@
-# $MirOS: src/bin/mksh/check.t,v 1.289 2009/07/05 13:56:46 tg Exp $
+# $MirOS: src/bin/mksh/check.t,v 1.290 2009/07/06 15:06:23 tg Exp $
 # $OpenBSD: bksl-nl.t,v 1.2 2001/01/28 23:04:56 niklas Exp $
 # $OpenBSD: history.t,v 1.5 2001/01/28 23:04:56 niklas Exp $
 # $OpenBSD: read.t,v 1.3 2003/03/10 03:48:16 david Exp $
@@ -25,7 +25,7 @@
 # http://www.research.att.com/~gsf/public/ifs.sh
 
 expected-stdout:
-	@(#)MIRBSD KSH R38 2009/07/05
+	@(#)MIRBSD KSH R38 2009/07/06
 description:
 	Check version of shell.
 stdin:
@@ -4804,6 +4804,42 @@ expected-stdout:
 	suspend='kill -STOP $$'
 	type='whence -v'
 ---
+name: aliases-funcdef-1
+description:
+	Check if POSIX functions take precedences over aliases
+stdin:
+	alias foo='echo makro'
+	foo() {
+		echo funktion
+	}
+	foo
+expected-stdout:
+	funktion
+---
+name: aliases-funcdef-2
+description:
+	Check if POSIX functions take precedences over aliases
+stdin:
+	alias foo='echo makro'
+	foo () {
+		echo funktion
+	}
+	foo
+expected-stdout:
+	funktion
+---
+name: aliases-funcdef-3
+description:
+	Check if aliases take precedences over Korn functions
+stdin:
+	alias foo='echo makro'
+	function foo {
+		echo funktion
+	}
+	foo
+expected-stdout:
+	makro
+---
 name: arrays-1
 description:
 	Check if Korn Shell arrays work as expected

lex.c

@@ -22,7 +22,7 @@
 
 #include "sh.h"
 
-__RCSID("$MirOS: src/bin/mksh/lex.c,v 1.88 2009/06/11 12:42:19 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/lex.c,v 1.89 2009/07/06 15:06:23 tg Exp $");
 
 /*
  * states while lexing word
@@ -159,7 +159,6 @@ yylex(int cf)
 	char *wp;		/* output word pointer */
 	char *sp, *dp;
 	int c2;
-	bool last_terminal_was_bracket;
 
  Again:
 	states[0].ls_state = -1;
@@ -881,8 +880,14 @@ yylex(int cf)
 	    state == SLETARRAY)	/* ONEWORD? */
 		return (LWORD);
 
-	last_terminal_was_bracket = c == '(';
+	/* unget terminator */
-	ungetsc(c);		/* unget terminator */
+	ungetsc(c);
+
+	/*
+	 * note: the alias-vs-function code below depends on several
+	 * interna: starting from here, source->str is not modified;
+	 * the way getsc() and ungetsc() operate; etc.
+	 */
 
 	/* copy word to unprefixed string ident */
 	sp = yylval.cp;
@@ -914,8 +919,31 @@ yylex(int cf)
 		}
 		if ((cf & ALIAS) && (p = ktsearch(&aliases, ident, h)) &&
 		    (p->flag & ISSET)) {
-			if (last_terminal_was_bracket)
+			/*
-				/* prefer functions over aliases */
+			 * this still points to the same character as the
+			 * ungetsc'd terminator from above
+			 */
+			const char *cp = source->str;
+
+			/* prefer POSIX but not Korn functions over aliases */
+			while (*cp == ' ' || *cp == '\t')
+				/*
+				 * this is like getsc() without skipping
+				 * over Source boundaries (including not
+				 * parsing ungetsc'd characters that got
+				 * pushed into an SREREAD) which is what
+				 * we want here anyway: find out whether
+				 * the alias name is followed by a POSIX
+				 * function definition (only the opening
+				 * parenthesis is checked though)
+				 */
+				++cp;
+			/* prefer functions over aliases */
+			if (*cp == '(' /*)*/)
+				/*
+				 * delete alias upon encountering function
+				 * definition
+				 */
 				ktdelete(p);
 			else {
 				Source *s = source;

mksh.1

@@ -1,4 +1,4 @@
-.\" $MirOS: src/bin/mksh/mksh.1,v 1.171 2009/07/06 09:37:03 tg Exp $
+.\" $MirOS: src/bin/mksh/mksh.1,v 1.172 2009/07/06 15:06:24 tg Exp $
 .\" $OpenBSD: ksh.1,v 1.129 2009/05/28 06:09:06 jmc Exp $
 .\"-
 .\" Copyright © 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
@@ -738,6 +738,9 @@ Mostly the same as
 (see
 .Sx Functions
 below).
+Whitespace (space or tab) after
+.Ar name
+will be ignored most of the time.
 .It Xo Ic time Op Fl p
 .Op Ar pipeline
 .Xc
@@ -2479,6 +2482,10 @@ untouched, so using
 inside a function interferes with using
 .Ic getopts
 outside the function).
+.It
+Bourne-style function definitions take precedence over alias dereferences
+and remove alias definitions upon encounter, while aliases take precedence
+over Korn-style functions.
 .El
 .Pp
 In the future, the following differences will also be added:

sh.h

@@ -122,9 +122,9 @@
 #define __SCCSID(x)	__IDSTRING(sccsid,x)
 
 #ifdef EXTERN
-__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.311 2009/07/05 13:56:48 tg Exp $");
+__RCSID("$MirOS: src/bin/mksh/sh.h,v 1.312 2009/07/06 15:06:25 tg Exp $");
 #endif
-#define MKSH_VERSION "R38 2009/07/05"
+#define MKSH_VERSION "R38 2009/07/06"
 
 #ifndef MKSH_INCLUDES_ONLY