Makefile: Add build-time check for files with initial tabs.

This should make it harder to reintroduce inappropriate indentation.

Signed-off-by: Ben Pfaff <[email protected]>
Acked-by: Justin Pettit <[email protected]>

Makefile.am

@@ -314,6 +314,21 @@ check-echo-n:
 	fi
 .PHONY: check-echo-n
 
+ALL_LOCAL += check-tabs
+check-tabs:
+	@cd $(srcdir); \
+	if test -e .git && (git --version) >/dev/null 2>&1 && \
+	  grep -ln "^	" \
+	    `git ls-files \
+	      | grep -v -f build-aux/initial-tab-whitelist` /dev/null \
+	      | $(EGREP) -v ':[ 	]*/?\*'; \
+	then \
+	  echo "See above for files that use tabs for indentation."; \
+	  echo "Please use spaces instead."; \
+	  exit 1; \
+	fi
+.PHONY: check-tabs
+
 ALL_LOCAL += thread-safety-check
 thread-safety-check:
 	@cd $(srcdir); \

build-aux/automake.mk

@@ -5,6 +5,7 @@ EXTRA_DIST += \
 	build-aux/dist-docs \
 	build-aux/dpdkstrip.py \
 	build-aux/generate-dhparams-c \
+	build-aux/initial-tab-whitelist \
 	build-aux/sodepends.py \
 	build-aux/soexpand.py \
 	build-aux/text2c \

build-aux/initial-tab-whitelist

@@ -0,0 +1,16 @@
+\.am$
+\.m4$
+\.mk$
+\.png$
+\.sln$
+^datapath/
+^include/linux/
+^include/windows/
+^lib/sflow
+^lib/getopt_long\.c$
+^lib/strsep\.c$
+^third-party/
+^windows/
+^xenserver/
+^debian/rules.modules$
+^debian/rules$