Makefile: consistently use @PLACEHOLDER@ to substitute

We have a bunch of placeholders in our scripts that we replace at build
time, for example by using sed(1). These placeholders come in three
different formats: @PLACEHOLDER@, @@PLACEHOLDER@@ and ++PLACEHOLDER++.

Next to being inconsistent it also creates a bit of a problem with
CMake, which only supports the first syntax in its `configure_file()`
function. To work around that we instead manually replace placeholders
via string operations, which is a hassle and removes safeguards that
CMake has to verify that we didn't forget to replace any placeholders.
Besides that, other build systems like Meson also support the CMake
syntax.

Unify our codebase to consistently use the syntax supported by such
build systems.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 22 insertions, 22 deletions

diff --git a/Makefile b/Makefile
index 1f8434a902..75e26d2e31 100644
--- a/Makefile
+++ b/Makefile
@@ -1555,10 +1555,10 @@ endif
 
 ifdef SANE_TOOL_PATH
 SANE_TOOL_PATH_SQ = $(subst ','\'',$(SANE_TOOL_PATH))
-BROKEN_PATH_FIX = 's|^\# @@BROKEN_PATH_FIX@@$$|git_broken_path_fix "$(SANE_TOOL_PATH_SQ)"|'
+BROKEN_PATH_FIX = 's|^\# @BROKEN_PATH_FIX@$$|git_broken_path_fix "$(SANE_TOOL_PATH_SQ)"|'
 PATH := $(SANE_TOOL_PATH):${PATH}
 else
-BROKEN_PATH_FIX = '/^\# @@BROKEN_PATH_FIX@@$$/d'
+BROKEN_PATH_FIX = '/^\# @BROKEN_PATH_FIX@$$/d'
 endif
 
 ifeq (,$(HOST_CPU))
@@ -2548,13 +2548,13 @@ GIT-SCRIPT-DEFINES: FORCE
 define cmd_munge_script
 sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
     -e 's|@SHELL_PATH@|$(SHELL_PATH_SQ)|' \
-    -e 's|@@DIFF@@|$(DIFF_SQ)|' \
-    -e 's|@@LOCALEDIR@@|$(localedir_SQ)|g' \
-    -e 's/@@USE_GETTEXT_SCHEME@@/$(USE_GETTEXT_SCHEME)/g' \
+    -e 's|@DIFF@|$(DIFF_SQ)|' \
+    -e 's|@LOCALEDIR@|$(localedir_SQ)|g' \
+    -e 's/@USE_GETTEXT_SCHEME@/$(USE_GETTEXT_SCHEME)/g' \
     -e $(BROKEN_PATH_FIX) \
-    -e 's|@@GITWEBDIR@@|$(gitwebdir_SQ)|g' \
-    -e 's|@@PERL@@|$(PERL_PATH_SQ)|g' \
-    -e 's|@@PAGER_ENV@@|$(PAGER_ENV_SQ)|g' \
+    -e 's|@GITWEBDIR@|$(gitwebdir_SQ)|g' \
+    -e 's|@PERL@|$(PERL_PATH_SQ)|g' \
+    -e 's|@PAGER_ENV@|$(PAGER_ENV_SQ)|g' \
     $@.sh >$@+
 endef
 
@@ -2611,7 +2611,7 @@ $(SCRIPT_PERL_GEN): % : %.perl GIT-PERL-DEFINES GIT-PERL-HEADER GIT-VERSION-FILE
 	    -e '	r GIT-PERL-HEADER' \
 	    -e '	G' \
 	    -e '}' \
-	    -e 's/@@GIT_VERSION@@/$(GIT_VERSION)/g' \
+	    -e 's/@GIT_VERSION@/$(GIT_VERSION)/g' \
 	    $< >$@+ && \
 	chmod +x $@+ && \
 	mv $@+ $@
@@ -2629,11 +2629,11 @@ GIT-PERL-HEADER: $(PERL_HEADER_TEMPLATE) GIT-PERL-DEFINES Makefile
 	INSTLIBDIR='$(perllibdir_SQ)' && \
 	INSTLIBDIR_EXTRA='$(PERLLIB_EXTRA_SQ)' && \
 	INSTLIBDIR="$$INSTLIBDIR$${INSTLIBDIR_EXTRA:+:$$INSTLIBDIR_EXTRA}" && \
-	sed -e 's=@@PATHSEP@@=$(pathsep)=g' \
-	    -e "s=@@INSTLIBDIR@@=$$INSTLIBDIR=g" \
-	    -e 's=@@PERLLIBDIR_REL@@=$(perllibdir_relative_SQ)=g' \
-	    -e 's=@@GITEXECDIR_REL@@=$(gitexecdir_relative_SQ)=g' \
-	    -e 's=@@LOCALEDIR_REL@@=$(localedir_relative_SQ)=g' \
+	sed -e 's=@PATHSEP@=$(pathsep)=g' \
+	    -e "s=@INSTLIBDIR@=$$INSTLIBDIR=g" \
+	    -e 's=@PERLLIBDIR_REL@=$(perllibdir_relative_SQ)=g' \
+	    -e 's=@GITEXECDIR_REL@=$(gitexecdir_relative_SQ)=g' \
+	    -e 's=@LOCALEDIR_REL@=$(localedir_relative_SQ)=g' \
 	    $< >$@+ && \
 	mv $@+ $@
 
@@ -2649,7 +2649,7 @@ else # NO_PERL
 $(SCRIPT_PERL_GEN) git-instaweb: % : unimplemented.sh
 	$(QUIET_GEN) \
 	sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
-	    -e 's|@@REASON@@|NO_PERL=$(NO_PERL)|g' \
+	    -e 's|@REASON@|NO_PERL=$(NO_PERL)|g' \
 	    unimplemented.sh >$@+ && \
 	chmod +x $@+ && \
 	mv $@+ $@
@@ -2670,13 +2670,13 @@ else # NO_PYTHON
 $(SCRIPT_PYTHON_GEN): % : unimplemented.sh
 	$(QUIET_GEN) \
 	sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
-	    -e 's|@@REASON@@|NO_PYTHON=$(NO_PYTHON)|g' \
+	    -e 's|@REASON@|NO_PYTHON=$(NO_PYTHON)|g' \
 	    unimplemented.sh >$@+ && \
 	chmod +x $@+ && \
 	mv $@+ $@
 endif # NO_PYTHON
 
-CONFIGURE_RECIPE = sed -e 's/@@GIT_VERSION@@/$(GIT_VERSION)/g' \
+CONFIGURE_RECIPE = sed -e 's/@GIT_VERSION@/$(GIT_VERSION)/g' \
 			configure.ac >configure.ac+ && \
 		   autoconf -o configure configure.ac+ && \
 		   $(RM) configure.ac+
@@ -3104,9 +3104,9 @@ endif
 perl/build/lib/%.pm: perl/%.pm GIT-PERL-DEFINES
 	$(call mkdir_p_parent_template)
 	$(QUIET_GEN) \
-	sed -e 's|@@LOCALEDIR@@|$(perl_localedir_SQ)|g' \
-	    -e 's|@@NO_GETTEXT@@|$(NO_GETTEXT_SQ)|g' \
-	    -e 's|@@NO_PERL_CPAN_FALLBACKS@@|$(NO_PERL_CPAN_FALLBACKS_SQ)|g' \
+	sed -e 's|@LOCALEDIR@|$(perl_localedir_SQ)|g' \
+	    -e 's|@NO_GETTEXT@|$(NO_GETTEXT_SQ)|g' \
+	    -e 's|@NO_PERL_CPAN_FALLBACKS@|$(NO_PERL_CPAN_FALLBACKS_SQ)|g' \
 	< $< > $@
 
 perl/build/man/man3/Git.3pm: perl/Git.pm
@@ -3231,8 +3231,8 @@ all:: $(TEST_PROGRAMS) $(test_bindir_programs) $(UNIT_TEST_PROGS) $(CLAR_TEST_PR
 bin-wrappers/%: wrap-for-bin.sh
 	$(call mkdir_p_parent_template)
 	$(QUIET_GEN)sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
-	     -e 's|@@BUILD_DIR@@|$(shell pwd)|' \
-	     -e 's|@@PROG@@|$(patsubst test-%,t/helper/test-%,$(@F))$(if $(filter-out $(BINDIR_PROGRAMS_NO_X),$(@F)),$(X),)|' < $< > $@ && \
+	     -e 's|@BUILD_DIR@|$(shell pwd)|' \
+	     -e 's|@PROG@|$(patsubst test-%,t/helper/test-%,$(@F))$(if $(filter-out $(BINDIR_PROGRAMS_NO_X),$(@F)),$(X),)|' < $< > $@ && \
 	chmod +x $@
 
 # GNU make supports exporting all variables by "export" without parameters.