kconfig: factor out ncurses check in a shell script

Cleaning up the lxdialog Makefile by factoring out the
ncurses compatibility checks.
This made the checks much more obvious and easier to extend.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

2 files changed, 79 insertions, 36 deletions

diff --git a/scripts/kconfig/lxdialog/Makefile b/scripts/kconfig/lxdialog/Makefile
index a45a13fb26ed..8f41d9a57aaa 100644
--- a/scripts/kconfig/lxdialog/Makefile
+++ b/scripts/kconfig/lxdialog/Makefile
@@ -1,42 +1,18 @@
-HOST_EXTRACFLAGS := -DLOCALE 
-ifeq ($(shell uname),SunOS)
-HOST_LOADLIBES   := -lcurses
-else
-HOST_LOADLIBES   := -lncurses
-endif
+# Makefile to build lxdialog package
+#
 
-ifeq (/usr/include/ncurses/ncurses.h, $(wildcard /usr/include/ncurses/ncurses.h))
-        HOST_EXTRACFLAGS += -I/usr/include/ncurses -DCURSES_LOC="<ncurses.h>"
-else
-ifeq (/usr/include/ncurses/curses.h, $(wildcard /usr/include/ncurses/curses.h))
-        HOST_EXTRACFLAGS += -I/usr/include/ncurses -DCURSES_LOC="<ncurses/curses.h>"
-else
-ifeq (/usr/include/ncurses.h, $(wildcard /usr/include/ncurses.h))
-        HOST_EXTRACFLAGS += -DCURSES_LOC="<ncurses.h>"
-else
-        HOST_EXTRACFLAGS += -DCURSES_LOC="<curses.h>"
-endif
-endif
-endif
+check-lxdialog   := $(srctree)/$(src)/check-lxdialog.sh
+HOST_EXTRACFLAGS := $(shell $(CONFIG_SHELL) $(check-lxdialog) -ccflags)
+HOST_LOADLIBES   := $(shell $(CONFIG_SHELL) $(check-lxdialog) -ldflags)
+ 
+HOST_EXTRACFLAGS += -DLOCALE 
+
+.PHONY: dochecklxdialog
+$(obj)/dochecklxdialog:
+        $(Q)$(CONFIG_SHELL) $(check-lxdialog) -check $(HOSTCC) $(HOST_LOADLIBES)
 
 hostprogs-y     := lxdialog
-always          := ncurses $(hostprogs-y)
+always          := $(hostprogs-y) dochecklxdialog
 
 lxdialog-objs := checklist.o menubox.o textbox.o yesno.o inputbox.o \
                  util.o lxdialog.o msgbox.o
-
-.PHONY: $(obj)/ncurses
-$(obj)/ncurses:
-        @echo "main() {}" > lxtemp.c
-        @if $(HOSTCC) lxtemp.c  $(HOST_LOADLIBES); then \
-                rm -f lxtemp.c a.out; \
-        else \
-                rm -f lxtemp.c; \
-                echo -e "\007" ;\
-                echo ">> Unable to find the Ncurses libraries." ;\
-                echo ">>" ;\
-                echo ">> You must install ncurses-devel in order" ;\
-                echo ">> to use 'make menuconfig'" ;\
-                echo ;\
-                exit 1 ;\
-        fi
diff --git a/scripts/kconfig/lxdialog/check-lxdialog.sh b/scripts/kconfig/lxdialog/check-lxdialog.sh
new file mode 100644
index 000000000000..a3c141b49670
--- /dev/null
+++ b/scripts/kconfig/lxdialog/check-lxdialog.sh
@@ -0,0 +1,67 @@
+#!/bin/sh
+# Check ncurses compatibility
+
+# What library to link
+ldflags()
+{
+        if [ `uname` == SunOS ]; then
+                echo '-lcurses'
+        else
+                echo '-lncurses'
+        fi
+}
+
+# Where is ncurses.h?
+ccflags()
+{
+        if [ -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="<ncurses/curses.h>"'
+        elif [ -f /usr/include/ncurses.h ]; then
+                echo '-DCURSES_LOC="<ncurses.h>"'
+        else
+                echo '-DCURSES_LOC="<curses.h>"'
+        fi
+}
+
+compiler=""
+# Check if we can link to ncurses
+check() {
+        echo "main() {}" | $compiler -xc -
+        if [ $? != 0 ]; then
+                echo " *** Unable to find the ncurses libraries."          1>&2
+                echo " *** make menuconfig require the ncurses libraries"  1>&2
+                echo " *** "                                               1>&2
+                echo " *** Install ncurses (ncurses-devel) and try again"  1>&2
+                echo " *** "                                               1>&2
+                exit 1
+        fi
+}
+
+usage() {
+        printf "Usage: $0 [-check compiler options|-header|-library]\n"
+}
+
+if [ $# == 0 ]; then
+        usage
+        exit 1
+fi
+
+case "$1" in
+        "-check")
+                shift
+                compiler="$@"
+                check
+                ;;
+        "-ccflags")
+                ccflags
+                ;;
+        "-ldflags")
+                ldflags
+                ;;
+        "*")
+                usage
+                exit 1
+                ;;
+esac