[v3,4/4] kconfig: refactor ncurses package checks for building mconf and nconf

diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index 8cee14b..e4ac102 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -173,59 +173,49 @@  help:
 	@echo  '  xenconfig       - Enable additional options for xen dom0 and guest kernel support'
 	@echo  '  tinyconfig	  - Configure the tiniest possible kernel'
 
-# lxdialog stuff
-check-lxdialog  := $(srctree)/$(src)/lxdialog/check-lxdialog.sh
-
-# Use recursively expanded variables so we do not call gcc unless
-# we really need to do so. (Do not call gcc as part of make mrproper)
-HOST_EXTRACFLAGS += $(shell $(CONFIG_SHELL) $(check-lxdialog) -ccflags) \
-                    -DLOCALE
-
 # ===========================================================================
 # Shared Makefile for the various kconfig executables:
 # conf:	  Used for defconfig, oldconfig and related targets
-# nconf:  Used for the nconfig target.
-#         Utilizes ncurses
-# mconf:  Used for the menuconfig target
-#         Utilizes the lxdialog package
 # object files used by all kconfig flavours
 
-lxdialog := lxdialog/checklist.o lxdialog/util.o lxdialog/inputbox.o
-lxdialog += lxdialog/textbox.o lxdialog/yesno.o lxdialog/menubox.o
-
 conf-objs	:= conf.o  zconf.tab.o
-mconf-objs     := mconf.o zconf.tab.o $(lxdialog)
-nconf-objs     := nconf.o zconf.tab.o nconf.gui.o
 kxgettext-objs	:= kxgettext.o zconf.tab.o
 
-hostprogs-y := conf nconf mconf kxgettext
+hostprogs-y := conf kxgettext
 
 targets		+= zconf.lex.c
 clean-files	+= gconf.glade.h
 clean-files     += config.pot linux.pot
 
-# Check that we have the required ncurses stuff installed for lxdialog (menuconfig)
-PHONY += $(obj)/dochecklxdialog
-$(addprefix $(obj)/, mconf.o $(lxdialog)): $(obj)/dochecklxdialog
-$(obj)/dochecklxdialog:
-	$(Q)$(CONFIG_SHELL) $(check-lxdialog) -check $(HOSTCC) $(HOST_EXTRACFLAGS) $(HOSTLOADLIBES_mconf)
-
-always := dochecklxdialog
-
 # Add environment specific flags
-HOST_EXTRACFLAGS += $(shell $(CONFIG_SHELL) $(srctree)/$(src)/check.sh $(HOSTCC) $(HOSTCFLAGS))
-HOST_EXTRACXXFLAGS += $(shell $(CONFIG_SHELL) $(srctree)/$(src)/check.sh $(HOSTCXX) $(HOSTCXXFLAGS))
-
+HOST_EXTRACFLAGS += $(shell $(CONFIG_SHELL) $(srctree)/$(src)/check.sh $(HOSTCC) $(HOSTCFLAGS)) \
+		    -DLOCALE
+HOST_EXTRACXXFLAGS += $(shell $(CONFIG_SHELL) $(srctree)/$(src)/check.sh $(HOSTCXX) $(HOSTCXXFLAGS)) \
+		    -DLOCALE
 # generated files seem to need this to find local include files
 HOSTCFLAGS_zconf.lex.o	:= -I$(src)
 HOSTCFLAGS_zconf.tab.o	:= -I$(src)
 
-HOSTLOADLIBES_mconf   = $(shell $(CONFIG_SHELL) $(check-lxdialog) -ldflags $(HOSTCC))
+# nconf: Used for the nconfig target based on ncurses
+hostprogs-y	+= nconf
+nconf-objs	:= nconf.o zconf.tab.o nconf.gui.o
+
+HOSTLOADLIBES_nconf	= $(shell . $(obj)/.nconf-cfg && echo $$libs)
+HOSTCFLAGS_nconf.o	= $(shell . $(obj)/.nconf-cfg && echo $$cflags)
+HOSTCFLAGS_nconf.gui.o	= $(shell . $(obj)/.nconf-cfg && echo $$cflags)
+
+$(obj)/nconf.o: $(obj)/.nconf-cfg
+
+# mconf: Used for the menuconfig target based on lxdialog
+hostprogs-y	+= mconf
+lxdialog	:= checklist.o inputbox.o menubox.o textbox.o util.o yesno.o
+mconf-objs	:= mconf.o zconf.tab.o $(addprefix lxdialog/, $(lxdialog))
+
+HOSTLOADLIBES_mconf = $(shell . $(obj)/.mconf-cfg && echo $$libs)
+$(foreach f, mconf.o $(lxdialog), \
+  $(eval HOSTCFLAGS_$f = $$(shell . $(obj)/.mconf-cfg && echo $$$$cflags)))
 
-HOSTLOADLIBES_nconf	= $(shell \
-				pkg-config --libs menuw panelw ncursesw 2>/dev/null \
-				|| pkg-config --libs menu panel ncurses 2>/dev/null \
-				|| echo "-lmenu -lpanel -lncurses"  )
+$(addprefix $(obj)/, mconf.o $(lxdialog)): $(obj)/.mconf-cfg
 
 # qconf: Used for the xconfig target based on Qt
 hostprogs-y	+= qconf
diff --git a/scripts/kconfig/lxdialog/check-lxdialog.sh b/scripts/kconfig/lxdialog/check-lxdialog.sh
deleted file mode 100755
index 6c0bcd9..0000000
--- a/scripts/kconfig/lxdialog/check-lxdialog.sh
+++ /dev/null
@@ -1,93 +0,0 @@ 
-#!/bin/sh
-# SPDX-License-Identifier: GPL-2.0
-# Check ncurses compatibility
-
-# What library to link
-ldflags()
-{
-	pkg-config --libs ncursesw 2>/dev/null && exit
-	pkg-config --libs ncurses 2>/dev/null && exit
-	for ext in so a dll.a dylib ; do
-		for lib in ncursesw ncurses curses ; do
-			$cc -print-file-name=lib${lib}.${ext} | grep -q /
-			if [ $? -eq 0 ]; then
-				echo "-l${lib}"
-				exit
-			fi
-		done
-	done
-	exit 1
-}
-
-# Where is ncurses.h?
-ccflags()
-{
-	if pkg-config --cflags ncursesw 2>/dev/null; then
-		echo '-DCURSES_LOC="<ncurses.h>" -DNCURSES_WIDECHAR=1'
-	elif pkg-config --cflags ncurses 2>/dev/null; then
-		echo '-DCURSES_LOC="<ncurses.h>"'
-	elif [ -f /usr/include/ncursesw/curses.h ]; then
-		echo '-I/usr/include/ncursesw -DCURSES_LOC="<curses.h>"'
-		echo ' -DNCURSES_WIDECHAR=1'
-	elif [ -f /usr/include/ncurses/ncurses.h ]; then
-		echo '-I/usr/include/ncurses -DCURSES_LOC="<ncurses.h>"'
-	elif [ -f /usr/include/ncurses/curses.h ]; then
-		echo '-I/usr/include/ncurses -DCURSES_LOC="<curses.h>"'
-	elif [ -f /usr/include/ncurses.h ]; then
-		echo '-DCURSES_LOC="<ncurses.h>"'
-	else
-		echo '-DCURSES_LOC="<curses.h>"'
-	fi
-}
-
-# Temp file, try to clean up after us
-tmp=.lxdialog.tmp
-trap "rm -f $tmp" 0 1 2 3 15
-
-# Check if we can link to ncurses
-check() {
-        $cc -x c - -o $tmp 2>/dev/null <<'EOF'
-#include CURSES_LOC
-main() {}
-EOF
-	if [ $? != 0 ]; then
-	    echo " *** Unable to find the ncurses libraries or the"       1>&2
-	    echo " *** required header files."                            1>&2
-	    echo " *** 'make menuconfig' requires the ncurses libraries." 1>&2
-	    echo " *** "                                                  1>&2
-	    echo " *** Install ncurses (ncurses-devel or libncurses-dev " 1>&2
-	    echo " *** depending on your distribution) and try again."    1>&2
-	    echo " *** "                                                  1>&2
-	    exit 1
-	fi
-}
-
-usage() {
-	printf "Usage: $0 [-check compiler options|-ccflags|-ldflags compiler options]\n"
-}
-
-if [ $# -eq 0 ]; then
-	usage
-	exit 1
-fi
-
-cc=""
-case "$1" in
-	"-check")
-		shift
-		cc="$@"
-		check
-		;;
-	"-ccflags")
-		ccflags
-		;;
-	"-ldflags")
-		shift
-		cc="$@"
-		ldflags
-		;;
-	"*")
-		usage
-		exit 1
-		;;
-esac
diff --git a/scripts/kconfig/lxdialog/dialog.h b/scripts/kconfig/lxdialog/dialog.h
index fcffd5b..52e30a0 100644
--- a/scripts/kconfig/lxdialog/dialog.h
+++ b/scripts/kconfig/lxdialog/dialog.h
@@ -35,7 +35,7 @@ 
 #ifdef __sun__
 #define CURS_MACROS
 #endif
-#include CURSES_LOC
+#include <ncurses.h>
 
 /*
  * Colors in ncurses 1.9.9e do not work properly since foreground and
diff --git a/scripts/kconfig/mconf-cfg.sh b/scripts/kconfig/mconf-cfg.sh
new file mode 100755
index 0000000..1c2fe90
--- /dev/null
+++ b/scripts/kconfig/mconf-cfg.sh
@@ -0,0 +1,44 @@ 
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+PKG="ncursesw"
+PKG2="ncurses"
+
+if pkg-config --exists $PKG; then
+	echo cflags=\"-DNCURSES_WIDECHAR=1 $(pkg-config --cflags $PKG)\"
+	echo libs=\"$(pkg-config --libs $PKG)\"
+	exit 0
+fi
+
+if pkg-config --exists $PKG2; then
+	echo cflags=\"$(pkg-config --cflags $PKG2)\"
+	echo libs=\"$(pkg-config --libs $PKG2)\"
+	exit 0
+fi
+
+# Unfortunately, some distributions (e.g. openSUSE) cannot find ncurses
+# by pkg-config.
+if [ -f /usr/include/ncursesw/ncurses.h ]; then
+	echo cflags=\"-DNCURSES_WIDECHAR=1 -I/usr/include/ncursesw\"
+	echo libs=\"-lncursesw\"
+	exit 0
+fi
+
+if [ -f /usr/include/ncurses/ncurses.h ]; then
+	echo cflags=\"-I/usr/include/ncurses\"
+	echo libs=\"-lncurses\"
+	exit 0
+fi
+
+if [ -f /usr/include/ncurses.h ]; then
+	echo cflags=\"\"
+	echo libs=\"-lncurses\"
+	exit 0
+fi
+
+echo >&2 "*"
+echo >&2 "* Unable to find the ncurses package."
+echo >&2 "* Install ncurses (ncurses-devel or libncurses-dev"
+echo >&2 "* depending on your distribution)."
+echo >&2 "*"
+exit 1
diff --git a/scripts/kconfig/nconf-cfg.sh b/scripts/kconfig/nconf-cfg.sh
new file mode 100644
index 0000000..4c95b4e
--- /dev/null
+++ b/scripts/kconfig/nconf-cfg.sh
@@ -0,0 +1,43 @@ 
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+PKG="ncursesw menuw panelw"
+PKG2="ncurses menu panel"
+
+if pkg-config --exists $PKG; then
+	echo cflags=\"-DNCURSES_WIDECHAR=1 $(pkg-config --cflags $PKG)\"
+	echo libs=\"$(pkg-config --libs $PKG)\"
+	exit 0
+fi
+
+if pkg-config --exists $PKG2; then
+	echo cflags=\"$(pkg-config --cflags $PKG2)\"
+	echo libs=\"$(pkg-config --libs $PKG2)\"
+	exit 0
+fi
+
+# Unfortunately, some distributions (e.g. openSUSE) cannot find ncurses
+# by pkg-config.
+if [ -f /usr/include/ncursesw/ncurses.h ]; then
+	echo cflags=\"-DNCURSES_WIDECHAR=1 -I/usr/include/ncursesw\"
+	echo libs=\"-lncursesw -lmenuw -lpanelw\"
+	exit 0
+fi
+
+if [ -f /usr/include/ncurses/ncurses.h ]; then
+	echo cflags=\"-I/usr/include/ncurses\"
+	echo libs=\"-lncurses -lmenu -lpanel\"
+	exit 0
+fi
+
+if [ -f /usr/include/ncurses.h ]; then
+	echo libs=\"-lncurses -lmenu -lpanel\"
+	exit 0
+fi
+
+echo >&2 "*"
+echo >&2 "* Unable to find the ncurses package."
+echo >&2 "* Install ncurses (ncurses-devel or libncurses-dev"
+echo >&2 "* depending on your distribution)."
+echo >&2 "*"
+exit 1