From 97fe23139626f1c181213c527159b8f5bb9b93a9 Mon Sep 17 00:00:00 2001
From: Peter Avalos <pavalos@dragonflybsd.org>
Date: Sun, 21 Aug 2011 13:26:53 -0700
Subject: [PATCH] sh: Do parameter expansion before printing PS4 (set -x).

Obtained-from:   FreeBSD 222907
---
 bin/sh/eval.c                              |  7 ++--
 bin/sh/expand.c                            |  3 +-
 bin/sh/parser.c                            | 46 +++++++++++++++++++++-
 bin/sh/parser.h                            |  3 +-
 bin/sh/sh.1                                |  4 +-
 tools/regression/bin/sh/execution/set-x3.0 |  9 +++++
 6 files changed, 64 insertions(+), 8 deletions(-)
 create mode 100644 tools/regression/bin/sh/execution/set-x3.0

diff --git a/bin/sh/eval.c b/bin/sh/eval.c
index 567a040d00..1bf6a0a57b 100644
--- a/bin/sh/eval.c
+++ b/bin/sh/eval.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  * @(#)eval.c	8.9 (Berkeley) 6/8/95
- * $FreeBSD: src/bin/sh/eval.c,v 1.107 2011/06/05 14:13:15 jilles Exp $
+ * $FreeBSD: src/bin/sh/eval.c,v 1.108 2011/06/09 23:12:23 jilles Exp $
  */
 
 #include <sys/time.h>
@@ -748,8 +748,9 @@ evalcommand(union node *cmd, int flgs, struct backcmd *backcmd)
 	/* Print the command if xflag is set. */
 	if (xflag) {
 		char sep = 0;
-		const char *p;
-		out2str(ps4val());
+		const char *p, *ps4;
+		ps4 = expandstr(ps4val());
+		out2str(ps4 != NULL ? ps4 : ps4val());
 		for (sp = varlist.list ; sp ; sp = sp->next) {
 			if (sep != 0)
 				out2c(' ');
diff --git a/bin/sh/expand.c b/bin/sh/expand.c
index fae5a3d889..1f8298548c 100644
--- a/bin/sh/expand.c
+++ b/bin/sh/expand.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  * @(#)expand.c	8.5 (Berkeley) 5/15/95
- * $FreeBSD: src/bin/sh/expand.c,v 1.86 2011/05/27 15:56:13 jilles Exp $
+ * $FreeBSD: src/bin/sh/expand.c,v 1.87 2011/06/09 23:12:23 jilles Exp $
  */
 
 #include <sys/types.h>
@@ -173,6 +173,7 @@ expandarg(union node *arg, struct arglist *arglist, int flag)
 	ifslastp = NULL;
 	argstr(arg->narg.text, flag);
 	if (arglist == NULL) {
+		STACKSTRNUL(expdest);
 		return;			/* here document expanded */
 	}
 	STPUTC('\0', expdest);
diff --git a/bin/sh/parser.c b/bin/sh/parser.c
index 86823338f8..82a2a770ec 100644
--- a/bin/sh/parser.c
+++ b/bin/sh/parser.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  * @(#)parser.c	8.7 (Berkeley) 5/16/95
- * $FreeBSD: src/bin/sh/parser.c,v 1.112 2011/05/21 22:03:06 jilles Exp $
+ * $FreeBSD: src/bin/sh/parser.c,v 1.113 2011/06/09 23:12:23 jilles Exp $
  */
 
 #include <stdio.h>
@@ -2027,3 +2027,47 @@ getprompt(void *unused __unused)
 	ps[i] = '\0';
 	return (ps);
 }
+
+
+const char *
+expandstr(char *ps)
+{
+	union node n;
+	struct jmploc jmploc;
+	struct jmploc *const savehandler = handler;
+	const int saveprompt = doprompt;
+	struct parsefile *const savetopfile = getcurrentfile();
+	struct parser_temp *const saveparser_temp = parser_temp;
+	const char *result = NULL;
+
+	if (!setjmp(jmploc.loc)) {
+		handler = &jmploc;
+		parser_temp = NULL;
+		setinputstring(ps, 1);
+		doprompt = 0;
+		readtoken1(pgetc(), DQSYNTAX, __DECONST(char *, "\n\n"), 0);
+		if (backquotelist != NULL)
+			error("Command substitution not allowed here");
+
+		n.narg.type = NARG;
+		n.narg.next = NULL;
+		n.narg.text = wordtext;
+		n.narg.backquote = backquotelist;
+
+		expandarg(&n, NULL, 0);
+		result = stackblock();
+		INTOFF;
+	}
+	handler = savehandler;
+	doprompt = saveprompt;
+	popfilesupto(savetopfile);
+	if (parser_temp != saveparser_temp) {
+		parser_temp_free_all();
+		parser_temp = saveparser_temp;
+	}
+	if (result != NULL) {
+		INTON;
+	} else if (exception == EXINT)
+		raise(SIGINT);
+	return result;
+}
diff --git a/bin/sh/parser.h b/bin/sh/parser.h
index 202e9784b8..c0d5fddc0b 100644
--- a/bin/sh/parser.h
+++ b/bin/sh/parser.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)parser.h	8.3 (Berkeley) 5/4/95
- * $FreeBSD: src/bin/sh/parser.h,v 1.17 2011/05/21 22:03:06 jilles Exp $
+ * $FreeBSD: src/bin/sh/parser.h,v 1.18 2011/06/09 23:12:23 jilles Exp $
  */
 
 /* control characters in argument strings */
@@ -86,3 +86,4 @@ void fixredir(union node *, const char *, int);
 int goodname(const char *);
 int isassignment(const char *);
 const char *getprompt(void *);
+const char *expandstr(char *);
diff --git a/bin/sh/sh.1 b/bin/sh/sh.1
index d3fbe815b8..05e9ecf15b 100644
--- a/bin/sh/sh.1
+++ b/bin/sh/sh.1
@@ -34,7 +34,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"	from: @(#)sh.1	8.6 (Berkeley) 5/4/95
-.\" $FreeBSD: src/bin/sh/sh.1,v 1.165 2011/05/21 22:03:06 jilles Exp $
+.\" $FreeBSD: src/bin/sh/sh.1,v 1.166 2011/06/09 23:12:23 jilles Exp $
 .\"
 .Dd August 21, 2011
 .Dt SH 1
@@ -328,7 +328,7 @@ Useful for debugging.
 Write each command
 (preceded by the value of the
 .Va PS4
-variable)
+variable subjected to parameter expansion and arithmetic expansion)
 to standard error before it is executed.
 Useful for debugging.
 .It "\ \ " Em tabcomplete
diff --git a/tools/regression/bin/sh/execution/set-x3.0 b/tools/regression/bin/sh/execution/set-x3.0
new file mode 100644
index 0000000000..aa4fb59cf8
--- /dev/null
+++ b/tools/regression/bin/sh/execution/set-x3.0
@@ -0,0 +1,9 @@
+# $FreeBSD: src/tools/regression/bin/sh/execution/set-x3.0,v 1.1 2011/06/09 23:12:23 jilles Exp $
+
+key='must contain this'
+PS4='$key+ '
+{ r=`set -x; { :; } 2>&1 >/dev/null`; } 2>/dev/null
+case $r in
+*"$key"*) true ;;
+*) false ;;
+esac
-- 
2.41.0