From c04743dac1025cb66e4e47bba52136ef1068bdb2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dag-Erling=20Sm=C3=B8rgrav?= <des@FreeBSD.org>
Date: Fri, 21 Oct 2011 11:08:25 +0000
Subject: [PATCH] It turns out that truss also used kdump's mkioctls script,
 and expected ioctlname() to return a pointer to the name rather than print
 it.  This did not show up in testing because truss had its own prototype for
 ioctlname(), so it would build fine and run fine as long as the program being
 traced did not issue an ioctl.

Teach mkioctls to generate different versions of ioctlname() based on its
first command-line argument.

Pointed out by:	Garrett Cooper <yanegomi@gmail.com>
---
 usr.bin/kdump/Makefile |  2 +-
 usr.bin/kdump/mkioctls | 51 ++++++++++++++++++++++++++++--------------
 usr.bin/truss/Makefile |  3 ++-
 usr.bin/truss/extern.h |  2 +-
 4 files changed, 38 insertions(+), 20 deletions(-)

diff --git a/usr.bin/kdump/Makefile b/usr.bin/kdump/Makefile
index 0af84ccb42d4..afa94bb7d127 100644
--- a/usr.bin/kdump/Makefile
+++ b/usr.bin/kdump/Makefile
@@ -22,7 +22,7 @@ CLEANFILES=	ioctl.c kdump_subr.c kdump_subr.h linux_syscalls.c
 
 ioctl.c: mkioctls
 	env MACHINE=${MACHINE} \
-	    sh ${.CURDIR}/mkioctls ${DESTDIR}/usr/include > ${.TARGET}
+	    sh ${.CURDIR}/mkioctls print ${DESTDIR}/usr/include > ${.TARGET}
 
 kdump_subr.h: mksubr
 	sh ${.CURDIR}/mksubr ${DESTDIR}/usr/include | \
diff --git a/usr.bin/kdump/mkioctls b/usr.bin/kdump/mkioctls
index 7ef2865b26e8..22ca26854dc1 100644
--- a/usr.bin/kdump/mkioctls
+++ b/usr.bin/kdump/mkioctls
@@ -1,20 +1,26 @@
 #!/bin/sh
 #
 # $FreeBSD$
+#
+# When editing this script, keep in mind that truss also uses it.
+#
 
 set -e
 
-if [ -z "$1" ]; then
-	echo "usage: sh $0 include-dir"
+if [ $# -ne 2 -o \( $1 != "print" -a $1 != "return" \) ]; then
+	echo "usage: sh $0 print|return include-dir"
 	exit 1
 fi
 
+style="$1"
+includedir="$2"
+
 LC_ALL=C; export LC_ALL
 
 # Build a list of headers that have ioctls in them.
 # XXX should we use an ANSI cpp?
 ioctl_includes=$(
-	cd $1
+	cd $includedir
 	find -H -s * -name '*.h' | grep -v '.*disk.*\.h' | \
 		xargs egrep -l \
 '^#[ 	]*define[ 	]+[A-Za-z_][A-Za-z0-9_]*[ 	]+_IO[^a-z0-9_]' |
@@ -33,7 +39,7 @@ esac
 
 awk -v x="$ioctl_includes" 'BEGIN {print x}' |
 	gcc -E -I$1 -dM -DCOMPAT_43TTY - |
-	awk -v ioctl_includes="$ioctl_includes" '
+	awk -v ioctl_includes="$ioctl_includes" -v style="$style" '
 BEGIN {
 	print "/* XXX obnoxious prerequisites. */"
 	print "#define COMPAT_43"
@@ -58,12 +64,19 @@ BEGIN {
 	print "#include <stdio.h>"
 	print "#include <cam/cam.h>"
 	print ""
-	print "void ioctlname(unsigned long val, int decimal);"
-	print ""
 	print ioctl_includes
 	print ""
-	print "void"
-	print "ioctlname(unsigned long val, int decimal)"
+	if (style == "print") {
+		print "void ioctlname(unsigned long val, int decimal);"
+		print ""
+		print "void"
+		print "ioctlname(unsigned long val, int decimal)"
+	} else {
+		print "const char *ioctlname(unsigned long val);"
+		print ""
+		print "const char *"
+		print "ioctlname(unsigned long val)"
+	}
 	print "{"
 	print "\tconst char *str = NULL;"
 	print ""
@@ -77,20 +90,24 @@ BEGIN {
 			break;
 	++i;
 	#
-	print("\t");
+	printf("\t");
 	if (n++ > 0)
-		print("else ");
+		printf("else ");
 	printf("if (val == %s)\n", $i);
 	printf("\t\tstr = \"%s\";\n", $i);
 }
 END {
-	print "\n"
-	print "\tif (str != NULL)\n"
-	print "\t\tprintf(\"%s\", str);\n"
-	print "\telse if (decimal)\n"
-	print "\t\tprintf(\"%lu\", val);\n"
-	print "\telse\n"
-	print "\t\tprintf(\"%#lx\", val);\n"
+	print ""
+	if (style == "print") {
+		print "\tif (str != NULL)"
+		print "\t\tprintf(\"%s\", str);"
+		print "\telse if (decimal)"
+		print "\t\tprintf(\"%lu\", val);"
+		print "\telse"
+		print "\t\tprintf(\"%#lx\", val);"
+	} else {
+		print "\treturn (str);"
+	}
 	print "}"
 }
 '
diff --git a/usr.bin/truss/Makefile b/usr.bin/truss/Makefile
index f80ac0367ea6..31f08d49b444 100644
--- a/usr.bin/truss/Makefile
+++ b/usr.bin/truss/Makefile
@@ -23,7 +23,8 @@ syscalls.h:	syscalls.master
 		${.CURDIR}/i386.conf
 
 ioctl.c: ${.CURDIR}/../kdump/mkioctls
-	sh ${.CURDIR}/../kdump/mkioctls ${DESTDIR}/usr/include > ${.TARGET}
+	env MACHINE=${MACHINE} \
+		/bin/sh ${.CURDIR}/../kdump/mkioctls return ${DESTDIR}/usr/include > ${.TARGET}
 
 .if ${MACHINE_CPUARCH} == "i386"
 SRCS+=	i386-linux.c linux_syscalls.h
diff --git a/usr.bin/truss/extern.h b/usr.bin/truss/extern.h
index e3ffc4f566a3..a56a01eb634f 100644
--- a/usr.bin/truss/extern.h
+++ b/usr.bin/truss/extern.h
@@ -35,7 +35,7 @@ extern int setup_and_wait(char **);
 extern int start_tracing(int);
 extern void restore_proc(int);
 extern void waitevent(struct trussinfo *);
-extern const char *ioctlname(register_t val);
+extern const char *ioctlname(unsigned long val);
 extern char *strsig(int sig);
 #ifdef __amd64__
 extern void amd64_syscall_entry(struct trussinfo *, int);