mk: filter duplicate configuration entries

Due to the hierarchy and the demand to keep the base config showing all
options, some config keys end up multiple times in the .config file.

Due to the way the actual config is sourced only the last entry is
important. That can confuse people changing values in .config which
are then ignored.

A suggested solution was to filter for duplicates at the end of the
actual config step which is implemented here.

Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>

diff --git a/mk/rte.sdkconfig.mk b/mk/rte.sdkconfig.mk
index 068d787..e93237f 100644 (file)
--- a/mk/rte.sdkconfig.mk
+++ b/mk/rte.sdkconfig.mk
@@ -79,11 +79,20 @@ $(RTE_OUTPUT):
 ifdef NODOTCONF
 $(RTE_OUTPUT)/.config: ;
 else
+# Generate config from template, if there are duplicates keep only the last.
+# To do so the temp config is checked for duplicate keys with cut/sort/uniq
+# Then for each of those identified duplicates as long as there are more than
+# just one left the last match is removed.
 $(RTE_OUTPUT)/.config: $(RTE_CONFIG_TEMPLATE) FORCE | $(RTE_OUTPUT)
        $(Q)if [ "$(RTE_CONFIG_TEMPLATE)" != "" -a -f "$(RTE_CONFIG_TEMPLATE)" ]; then \
                $(CPP) -undef -P -x assembler-with-cpp \
                -ffreestanding \
                -o $(RTE_OUTPUT)/.config_tmp $(RTE_CONFIG_TEMPLATE) ; \
+               for config in $$(grep -v "^#" $(RTE_OUTPUT)/.config_tmp | cut -d"=" -f1 | sort | uniq -d); do \
+                       while [ $$(grep "^$${config}=" $(RTE_OUTPUT)/.config_tmp -c ) -gt 1 ]; do \
+                               sed -i "0,/^$${config}=/{//d}" $(RTE_OUTPUT)/.config_tmp; \
+                       done; \
+               done; \
                if ! cmp -s $(RTE_OUTPUT)/.config_tmp $(RTE_OUTPUT)/.config; then \
                        cp $(RTE_OUTPUT)/.config_tmp $(RTE_OUTPUT)/.config ; \
                        cp $(RTE_OUTPUT)/.config_tmp $(RTE_OUTPUT)/.config.orig ; \