Better header detection for source formatting

Makefile

@@ -2,7 +2,7 @@ NAME = WalrusRPG
 
 DEBUG = FALSE
 
-CFLAGS_COMMON = -Wall -W $(addprefix -I,$(INCLUDE)) -MMD -MP
+CFLAGS_COMMON = -Wall -W $(addprefix -I,$(INCLUDE) $(INCLUDE_EXT)) -MMD -MP
 
 ifeq ($(DEBUG),FALSE)
 	CFLAGS_COMMON += -Ofast -flto
@@ -21,6 +21,7 @@ SRCS_CPP :=
 OBJS = $(BUILT_SRCS_C:%.c=%.o) $(BUILD_SRCS_CPP:%.cpp=%.o)
 OBJS += $(addprefix $(OUT)/,$(SRCS_C:%.c=%.o) $(SRCS_CPP:%.cpp=%.o))
 INCLUDE :=
+INCLUDE_EXT :=
 BUILT_SRCS :=
 BUILT_SRCS_C :=
 BUILT_SRCS_CPP :=

external/rules.mk

@@ -2,4 +2,4 @@ external_LOCAL_PATH := $(call whereami)
 
 include $(wildcard $(external_LOCAL_PATH)/*/rules.mk)
 
-INCLUDE += $(external_LOCAL_PATH)/tinystl/include
+INCLUDE_EXT += $(external_LOCAL_PATH)/tinystl/include

rules.mk

@@ -36,9 +36,9 @@ clean:
 
 format:
 	@echo "Formatting source using clang-format"
-	@clang-format -i -style=file $(SRCS_C) $(SRCS_CPP) $(wildcard $(addsuffix /*.h,$(INCLUDE)))
+	@clang-format -i -style=file $(SRCS_C) $(SRCS_CPP) $(shell find $(INCLUDE) -name *.h)
 
 include:
-	@echo -n $(addprefix -I ,$(INCLUDE))
+	@echo -n $(addprefix -I ,$(INCLUDE) $(INCLUDE_EXT))
 
 .FORCE: