[Buildroot] [PATCH 1/2] Busybox: save a copy of the config file

[Stephan Hoffmann]

"make busybox-xconfig" stores the changes made in the build
directory. Calling "make clean && make" later discards and
replaces them with the default values. This is not what a
user expects.

This patch saves a copy of the modified config file as
$(TOPDIR)/busybox-config and retrieves it from there after
"make clean". $(TOPDIR)/busybox-config is removed when a new
defconfig is made.

Signed-off-by: Stephan Hoffmann <sho at relinux.de>
---
 Makefile                   |    2 ++
 package/busybox/busybox.mk |   20 ++++++++++++++++++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 6f8ed0e..95ed683 100644
--- a/Makefile
+++ b/Makefile
@@ -673,10 +673,12 @@ silentoldconfig: $(BUILD_DIR)/buildroot-config/conf outputmakefile
 
 defconfig: $(BUILD_DIR)/buildroot-config/conf outputmakefile
 	@mkdir -p $(BUILD_DIR)/buildroot-config
+	rm -f $(TOPDIR)/busybox-config
 	@$(COMMON_CONFIG_ENV) $< --defconfig$(if $(BR2_DEFCONFIG),=$(BR2_DEFCONFIG)) $(CONFIG_CONFIG_IN)
 
 %_defconfig: $(BUILD_DIR)/buildroot-config/conf $(TOPDIR)/configs/%_defconfig outputmakefile
 	@mkdir -p $(BUILD_DIR)/buildroot-config
+	rm -f $(TOPDIR)/busybox-config
 	@$(COMMON_CONFIG_ENV) $< --defconfig=$(TOPDIR)/configs/$@ $(CONFIG_CONFIG_IN)
 
 savedefconfig: $(BUILD_DIR)/buildroot-config/conf outputmakefile
diff --git a/package/busybox/busybox.mk b/package/busybox/busybox.mk
index 9154c08..b81a4f5 100644
--- a/package/busybox/busybox.mk
+++ b/package/busybox/busybox.mk
@@ -33,6 +33,9 @@ BUSYBOX_CFLAGS_busybox += -ltirpc
 endif
 
 BUSYBOX_BUILD_CONFIG = $(BUSYBOX_DIR)/.config
+# Place to save configuration when "make clean" is issued
+BUSYBOX_CONFIG_SAVE = $(TOPDIR)/busybox-config
+
 # Allows the build system to tweak CFLAGS
 BUSYBOX_MAKE_ENV = \
 	$(TARGET_MAKE_ENV) \
@@ -47,8 +50,9 @@ BUSYBOX_MAKE_OPTS = \
 	CONFIG_PREFIX="$(TARGET_DIR)" \
 	SKIP_STRIP=y
 
+# Name the local variable different from environment to be able to distinguish later
 ifndef BUSYBOX_CONFIG_FILE
-	BUSYBOX_CONFIG_FILE = $(call qstrip,$(BR2_PACKAGE_BUSYBOX_CONFIG))
+	LOCAL_BUSYBOX_CONFIG_FILE = $(call qstrip,$(BR2_PACKAGE_BUSYBOX_CONFIG))
 endif
 
 define BUSYBOX_PERMISSIONS
@@ -126,9 +130,19 @@ define BUSYBOX_NETKITTELNET
 endef
 endif
 
+ifndef BUSYBOX_CONFIG_FILE
+# Keep a local copy of the config file to preserve changes over "make clean"
+define BUSYBOX_COPY_CONFIG
+	test ! -f $(BUSYBOX_CONFIG_SAVE) && \
+		cp -f $(LOCAL_BUSYBOX_CONFIG_FILE) $(BUSYBOX_CONFIG_SAVE); \
+	cp -f $(BUSYBOX_CONFIG_SAVE) $(BUSYBOX_BUILD_CONFIG)
+endef
+else
+# When the environmant variable is present we always want to use this config file
 define BUSYBOX_COPY_CONFIG
 	cp -f $(BUSYBOX_CONFIG_FILE) $(BUSYBOX_BUILD_CONFIG)
 endef
+endif
 
 # Disable shadow passwords support if unsupported by the C library
 ifeq ($(BR2_TOOLCHAIN_HAS_SHADOW_PASSWORDS),)
@@ -220,8 +234,10 @@ $(eval $(generic-package))
 busybox-menuconfig busybox-xconfig busybox-gconfig: busybox-patch
 	$(BUSYBOX_MAKE_ENV) $(MAKE) $(BUSYBOX_MAKE_OPTS) -C $(BUSYBOX_DIR) \
 		$(subst busybox-,,$@)
+	cp -f $(BUSYBOX_BUILD_CONFIG) $(BUSYBOX_CONFIG_SAVE)
 	rm -f $(BUSYBOX_DIR)/.stamp_built
 	rm -f $(BUSYBOX_DIR)/.stamp_target_installed
 
 busybox-update-config:
-	cp -f $(BUSYBOX_BUILD_CONFIG) $(BUSYBOX_CONFIG_FILE)
+	cp -f $(BUSYBOX_BUILD_CONFIG) $(LOCAL_BUSYBOX_CONFIG_FILE)
+
-- 
1.7.0.4