coccicheck: make batch size of 0 mean "unlimited"

If you have the memory to handle it, the ideal case is to run a single
spatch invocation with all of the source files. But the only way to do
so now is to pick an arbitrarily large batch size. Let's make "0" do
this, which is a little friendlier (and doesn't otherwise have a useful
meaning).

Signed-off-by: Jeff King <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: peff

Makefile

@@ -1176,6 +1176,7 @@ SP_EXTRA_FLAGS =
 
 # For the 'coccicheck' target; setting SPATCH_BATCH_SIZE higher will
 # usually result in less CPU usage at the cost of higher peak memory.
+# Setting it to 0 will feed all files in a single spatch invocation.
 SPATCH_FLAGS = --all-includes --patch .
 SPATCH_BATCH_SIZE = 1
 
@@ -2792,7 +2793,12 @@ endif
 
 %.cocci.patch: %.cocci $(COCCI_SOURCES)
 	@echo '    ' SPATCH $<; \
-	if ! echo $(COCCI_SOURCES) | xargs -n $(SPATCH_BATCH_SIZE) \
+	if test $(SPATCH_BATCH_SIZE) = 0; then \
+		limit=; \
+	else \
+		limit='-n $(SPATCH_BATCH_SIZE)'; \
+	fi; \
+	if ! echo $(COCCI_SOURCES) | xargs $$limit \
 		$(SPATCH) --sp-file $< $(SPATCH_FLAGS) \
 		>$@+ 2>$@.log; \
 	then \