Basic framework for checking config file version

Signed-off-by: Alexey Neyman <stilor@att.net>

4 files changed, 119 insertions, 33 deletions

diff --git a/config/global.in b/config/global.in
index 0dff199..a19667b 100644
--- a/config/global.in
+++ b/config/global.in
@@ -1,14 +1,47 @@
 # Overall toolchain configuration: paths, jobs, etc...
 
-config CT_VERSION
+config VERSION
     string
     option env="CT_VERSION"
 
+# Config version checking framework. If CONFIG_VERSION is unset in the current .config
+# or defconfig, it is loaded as 0 (possibly triggering a user prompt during 'ct-ng oldconfig').
+# If the value of CONFIG_VERSION is older than CONFIG_VERSION_CURRENT, we'll advice the user
+# to run the configuration through an upgrade. If it is newer, we'll error out - I have no
+# crystal orb to perform the downgrade.
+
+# Hack to make kconfig save/load the value for CONFIG_VERSION. Set to empty value (for
+# normal operations like 'ct-ng menuconfig'); 'load' for creating a configuration from a (potentially)
+# old file, i.e. 'ct-ng <sample>' or 'ct-ng oldconfig'; 'save' for saving the current configuration,
+# i.e. 'ct-ng saveconfig' or 'ct-ng savedefconfig'.
+config VCHECK
+    string
+    option env="CT_VCHECK"
+
+config CONFIG_VERSION_CURRENT
+    string
+    default -1 if VCHECK = "save"
+    default 1
+
+config CONFIG_VERSION
+    string
+    prompt "** make it changeable **" if VCHECK = "load" || VCHECK = "save"
+    default 0 if VCHECK = "load" || VCHECK = "save"
+    default CONFIG_VERSION_CURRENT
+
+if VCHECK = "warning"
+comment "*************************************************************************"
+comment "Loaded configuration was generated by a previous version of crosstool-NG."
+comment "Saving it will mark the configuration as up-to-date without verifying it."
+comment "It is recommended to run \"ct-ng upgradeconfig\" before making any         "
+comment "changes to the configuration.                                            "
+comment "*************************************************************************"
+endif
+
 # Allow unconditional usage of tristates
 config MODULES
-    bool
+    def_bool y
     option modules
-    default y
 
 menu "Paths and misc options"
 
diff --git a/ct-ng.in b/ct-ng.in
index 0b5e517..fddc464 100644
--- a/ct-ng.in
+++ b/ct-ng.in
@@ -1,4 +1,5 @@
 #!@MAKE@ -rf
+# vim: set filetype=make :
 # Makefile for crosstool-NG.
 # Copyright 2006 Yann E. MORIN <yann.morin.1998@free.fr>
 
@@ -32,6 +33,10 @@ endif
 # This is crosstool-NG version string
 export CT_VERSION:=@PACKAGE_VERSION@
 
+# Export with an empty value: this masks the version detection variable in
+# user-visible configurators, and suppresses a warning from kconfig.
+export CT_VCHECK=
+
 # Download agents used by scripts.mk
 CT_WGET     := @wget@
 CT_CURL     := @curl@
@@ -93,10 +98,9 @@ FORCE:
 # Top file of crosstool-NG configuration
 export KCONFIG_TOP = $(CT_LIB_DIR)/config/config.in
 
-# We need CONF for savedefconfig in scripts/saveSample.sh
-export CONF  := $(CT_LIBEXEC_DIR)/conf
-MCONF := $(CT_LIBEXEC_DIR)/mconf
-NCONF := $(CT_LIBEXEC_DIR)/nconf
+CONF            := $(CT_LIBEXEC_DIR)/conf
+CONF-menuconfig := $(CT_LIBEXEC_DIR)/mconf
+CONF-nconfig    := $(CT_LIBEXEC_DIR)/nconf
 
 # Used by conf/mconf/nconf to find the .in files
 # TBD needed? We do supply the defconfig name explicitly below
@@ -107,26 +111,26 @@ export srctree=$(CT_LIB_DIR)
 check-config:
 	@[ ! -e .config -o -f .config ] || { echo ".config is not a regular file:"; ls -dl .config; exit 1; } >&2
 
-menuconfig: check-config
-	@$(CT_ECHO) "  CONF  $@"
-	$(SILENT)$(MCONF) $(KCONFIG_TOP)
-
-nconfig: check-config
+menuconfig nconfig: check-config
 	@$(CT_ECHO) "  CONF  $@"
-	$(SILENT)$(NCONF) $(KCONFIG_TOP)
+	$(SILENT)if [ ! -f .config ] || CT_VCHECK=strict $(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config; then \
+		$(CONF-$@) $(KCONFIG_TOP); \
+	else \
+		CT_VCHECK=warning $(CONF-$@) $(KCONFIG_TOP); \
+	fi
 
 oldconfig: .config check-config
 	@$(CT_ECHO) "  CONF  $@"
-	$(SILENT)$(sed) -i -r -f $(CT_LIB_DIR)/scripts/upgrade.sed $<
+	@$(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config
 	$(SILENT)$(CONF) --silent$@ $(KCONFIG_TOP)
 
 savedefconfig: .config check-config
 	@$(CT_ECHO) '  GEN   $@'
-	$(SILENT)$(CONF) --savedefconfig=$${DEFCONFIG-defconfig} $(KCONFIG_TOP)
+	$(SILENT)CT_VCHECK=save $(CONF) --savedefconfig=$${DEFCONFIG-defconfig} $(KCONFIG_TOP)
 
 defconfig: check-config
 	@$(CT_ECHO) '  CONF  $@'
-	$(SILENT)$(CONF) --defconfig=$${DEFCONFIG-defconfig} $(KCONFIG_TOP)
+	$(SILENT)CT_VCHECK=save $(CONF) --defconfig=$${DEFCONFIG-defconfig} $(KCONFIG_TOP)
 
 # Always be silent, the stdout an be >.config
 extractconfig:
diff --git a/samples/samples.mk b/samples/samples.mk
index 13f8779..6305800 100644
--- a/samples/samples.mk
+++ b/samples/samples.mk
@@ -19,13 +19,14 @@ CT_UPDATE_SAMPLES := no
 # This part deals with the samples help entries
 
 help-config::
-	@echo  '  show-config        - show a brief overview of current configuration'
+	@echo  '  show-config        - Show a brief overview of current configuration'
 	@echo  '  saveconfig         - Save current config as a preconfigured target'
+	@echo  '  upgradeconfig      - Upgrade config file to current crosstool-NG'
 
 help-samples::
-	@echo  '  list-samples       - prints the list of all samples (for scripting)'
-	@echo  '  show-<sample>      - show a brief overview of <sample> (list with list-samples)'
-	@echo  '  <sample>           - preconfigure crosstool-NG with <sample> (list with list-samples)'
+	@echo  '  list-samples       - Prints the list of all samples (for scripting)'
+	@echo  '  show-<sample>      - Show a brief overview of <sample> (list with list-samples)'
+	@echo  '  <sample>           - Preconfigure crosstool-NG with <sample> (list with list-samples)'
 	@echo  '  build-all[.#]      - Build *all* samples (list with list-samples) and install in'
 	@echo  '                       $${CT_PREFIX} (set to ~/x-tools by default)'
 
@@ -34,7 +35,7 @@ help-distrib::
 	@echo  '  update-samples     - Regenerate sample configurations using the current Kconfig'
 
 help-env::
-	@echo  '  CT_PREFIX=dir      - install samples in dir (see action "build-all", above).'
+	@echo  '  CT_PREFIX=dir      - Install samples in dir (see action "build-all", above).'
 
 # ----------------------------------------------------------
 # This part deals with printing samples information
@@ -43,6 +44,7 @@ help-env::
 PHONY += show-config
 show-config: .config
 	@cp .config .config.sample
+	@$(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config
 	@$(bash) $(CT_LIB_DIR)/scripts/show-config.sh -v current
 	@rm -f .config.sample
 
@@ -50,8 +52,10 @@ show-config: .config
 PHONY += $(patsubst %,show-%,$(CT_SAMPLES))
 $(patsubst %,show-%,$(CT_SAMPLES)): show-%:
 	@KCONFIG_CONFIG=$$(pwd)/.config.sample	\
-	    $(CONF) --defconfig=$(call sample_dir,$*)/crosstool.config   \
+	    CT_VCHECK=load \
+        $(CONF) --defconfig=$(call sample_dir,$*)/crosstool.config   \
 	            $(KCONFIG_TOP) >/dev/null
+	@$(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config.sample
 	@$(bash) $(CT_LIB_DIR)/scripts/show-config.sh -v $*
 	@rm -f .config.sample
 
@@ -74,8 +78,10 @@ list-samples-pre: FORCE
 PHONY += $(patsubst %,list-%,$(CT_SAMPLES))
 $(patsubst %,list-%,$(CT_SAMPLES)): list-%:
 	@KCONFIG_CONFIG=$$(pwd)/.config.sample	\
+	    CT_VCHECK=load \
 	    $(CONF) --defconfig=$(call sample_dir,$*)/crosstool.config   \
 	            $(KCONFIG_TOP) >/dev/null
+	@$(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config.sample
 	@$(bash) $(CT_LIB_DIR)/scripts/show-config.sh $*
 	@rm -f .config.sample
 
@@ -88,19 +94,20 @@ list-samples-short: FORCE
 # Check one sample
 PHONY += $(patsubst %,check-%,$(CT_SAMPLES))
 $(patsubst %,check-%,$(CT_SAMPLES)): check-%:
-	@export KCONFIG_CONFIG=$$(pwd)/.config.sample;                                  \
+	@eset -e; xport KCONFIG_CONFIG=$$(pwd)/.config.sample;                          \
 	 CT_NG_SAMPLE=$(call sample_dir,$*)/crosstool.config;                           \
-	 $(CONF) -s --defconfig=$${CT_NG_SAMPLE} $(KCONFIG_TOP) &>/dev/null;            \
-	 $(CONF) -s --savedefconfig=$$(pwd)/.defconfig $(KCONFIG_TOP) &>/dev/null;      \
+	 CT_VCHECK=load $(CONF) -s --defconfig=$${CT_NG_SAMPLE} $(KCONFIG_TOP) &>/dev/null;            \
+	 CT_UPGRADECONFIG=yes $(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config.sample;           \
+	 CT_VCHECK=save $(CONF) -s --savedefconfig=$$(pwd)/.defconfig $(KCONFIG_TOP) &>/dev/null;      \
 	 old_sha1=$$( sha1sum "$${CT_NG_SAMPLE}" |cut -d ' ' -f 1 );                    \
 	 new_sha1=$$( sha1sum .defconfig |cut -d ' ' -f 1 );                            \
 	 if [ $${old_sha1} != $${new_sha1} ]; then                                      \
-	    if [ $(CT_UPDATE_SAMPLES) = yes ]; then                                     \
-	        echo "Updating $*";                                                     \
-		mv .defconfig "$${CT_NG_SAMPLE}";                                       \
+		if [ $(CT_UPDATE_SAMPLES) = yes ]; then                                     \
+			echo "Updating $*";                                                     \
+			mv .defconfig "$${CT_NG_SAMPLE}";                                       \
 	    else                                                                        \
-		echo "$* needs update:";                                                \
-		diff -d -U 0 "$${CT_NG_SAMPLE}" .defconfig |tail -n +4;                    \
+			echo "$* needs update:";                                                \
+			diff -d -U 0 "$${CT_NG_SAMPLE}" .defconfig |tail -n +4;                 \
 	    fi;                                                                         \
 	 fi
 	@rm -f .config.sample* .defconfig
@@ -120,7 +127,10 @@ samples:
 
 # Save a sample
 saveconfig: .config samples
-	$(SILENT)$(bash) $(CT_LIB_DIR)/scripts/saveSample.sh
+	$(SILENT)CT_VCHECK=save CONF=$(CONF) $(bash) $(CT_LIB_DIR)/scripts/saveSample.sh
+
+upgradeconfig: .config
+	$(SILENT)CT_UPGRADECONFIG=yes $(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config
 
 # The 'sample_dir' function prints the directory in which the sample is,
 # searching first in local samples, then in global samples
@@ -132,7 +142,8 @@ endef
 PHONY += $(CT_SAMPLES)
 $(CT_SAMPLES): check-config
 	@$(CT_ECHO) "  CONF  $@"
-	$(SILENT)$(CONF) --defconfig=$(call sample_dir,$@)/crosstool.config $(KCONFIG_TOP)
+	$(SILENT)CT_VCHECK=load $(CONF) --defconfig=$(call sample_dir,$@)/crosstool.config $(KCONFIG_TOP)
+	@CT_VCHECK=strict $(bash) $(CT_LIB_DIR)/scripts/version-check.sh .config
 	@echo
 	@echo  '***********************************************************'
 	@echo
@@ -169,7 +180,7 @@ target_triplet = $(if $(findstring $(__comma),$(1)),$(word 2,$(subst $(__comma),
 # $1: sample name (target tuple, or host/target tuples separated by a comma)
 define build_sample
 	@$(CT_ECHO) '  CONF  $(1)'
-	$(SILENT)$(CONF) -s --defconfig=$(call sample_dir,$(1))/crosstool.config $(KCONFIG_TOP)
+	$(SILENT)CT_VCHECK=load $(CONF) -s --defconfig=$(call sample_dir,$(1))/crosstool.config $(KCONFIG_TOP)
 	$(SILENT)[ -n "$(CT_PREFIX)" ] && $(sed) -i -r -e 's:^(CT_PREFIX=).*$$:\1"$(CT_PREFIX)":;' .config || :
 	$(SILENT)$(sed) -i -r -e 's:^.*(CT_LOG_(WARN|INFO|EXTRA|DEBUG|ALL)).*$$:# \1 is not set:;' .config
 	$(SILENT)$(sed) -i -r -e 's:^.*(CT_LOG_ERROR).*$$:\1=y:;' .config
diff --git a/scripts/version-check.sh b/scripts/version-check.sh
new file mode 100644
index 0000000..c4a2bd0
--- /dev/null
+++ b/scripts/version-check.sh
@@ -0,0 +1,38 @@
+# This script checks the version of the configuration file and either
+# alerts the user about the need to run the upgrade, or attempts to
+# perform such an upgrade.
+
+CFGFILE="${1}"
+
+. "${CT_LIB_DIR}/scripts/functions"
+. "${CFGFILE}"
+if [ "${CT_CONFIG_VERSION_CURRENT}" == "${CT_CONFIG_VERSION}" ]; then
+    # Nothing to do
+    exit 0
+fi
+
+if [ -z "${CT_UPGRADECONFIG}" ]; then
+    if [ "${CT_CONFIG_VERSION}" != "0" ]; then
+        oldversion="is version ${CT_CONFIG_VERSION}"
+    else
+        oldversion="has no version"
+    fi
+    cat 2>&1 <<EOF
+
+Configuration file was generated by an older version of crosstool-NG;
+configuration file ${oldversion}; crosstool-NG currently expects
+version ${CT_CONFIG_VERSION_CURRENT}. If this configuration file was generated by a crosstool-NG
+version 1.23.0 or later, you can run 'ct-ng upgradeconfig'.
+Compatibility with previous releases is not guaranteed. In any case,
+verify the resulting configuration.
+
+EOF
+    if [ "${CT_VCHECK}" = "strict" ]; then
+        exit 1
+    else
+        exit 0
+    fi
+fi
+
+echo "TBD not implemented yet" >&2
+exit 1