From 8703edbec8e8deb344606af5bd28fbf833e019da Mon Sep 17 00:00:00 2001
From: MadMaurice <madmaurice@zom.bi>
Date: Fri, 1 Sep 2023 09:18:32 +0200
Subject: [PATCH] Makefile - Rework build system a bit

---
 .gitignore |  1 +
 Makeconf   | 33 +++++++++++++++++++++++----------
 Makefile   | 48 +++++++++++++++++++++++-------------------------
 3 files changed, 47 insertions(+), 35 deletions(-)

diff --git a/.gitignore b/.gitignore
index b7a2d4f..8b80bd7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@
 /libemu.a
 /vgbc.test
 /vgbc.inspect
+*.d
diff --git a/Makeconf b/Makeconf
index ac8fd84..48f99c4 100644
--- a/Makeconf
+++ b/Makeconf
@@ -1,12 +1,25 @@
-modules := memory/device \
-           memory/bus \
-           memory/ram \
-           memory/bootrom_overlay \
-           memory/register \
-		   memory/bank \
-           memory/mbc/mbc1 \
-           cpu/cpu \
-           cpu/decoder \
-           cartridge/cartridge
+TARGETS := libemu.a vgbc vgbc.test vgbc.inspect
+
+cmd_libemu.a = ar -rc $@ $^
+verb_libemu.a = pack
+modules_libemu.a := memory/device.o \
+                    memory/bus.o \
+                    memory/ram.o \
+                    memory/bootrom_overlay.o \
+                    memory/register.o \
+                    memory/bank.o \
+                    memory/mbc/mbc1.o \
+                    cpu/cpu.o \
+                    cpu/decoder.o \
+                    cartridge/cartridge.o
+
+modules_vgbc := main.o libemu.a
+verb_vgbc := link
+
+modules_vgbc.test := $(patsubst %.cpp,%.o,$(wildcard tests/*.cpp)) libemu.a
+verb_vgbc.test := link
+
+modules_vgbc.inspect := cartridge/inspector.o libemu.a
+verb_vgbc.inspect := link
 
 CXX_FLAGS := -I $(CURDIR)
diff --git a/Makefile b/Makefile
index 73d0448..d5860fd 100644
--- a/Makefile
+++ b/Makefile
@@ -1,40 +1,38 @@
 include Makeconf
 
-test-srcs := $(wildcard tests/*.cpp)
+# Auto tracking of headers
+CXX_FLAGS += -MMD
+depfiles := $(wildcard *.d **/*.d)
 
-emu-objs := $(addsuffix .o,$(modules))
-test-objs := $(patsubst %.cpp,%.o,$(test-srcs))
-clean-objs := $(emu-objs) $(test-objs) libemu.a vgbc vgbc.test vgbc.inspect main.o
+clean-objs := $(foreach t,$(TARGETS),$(modules_$(t))) $(depfiles)
+cmd = $(VERBOSE)g++ $(CXX_FLAGS) -o $@ $^
+msg = $(or $(verb_$@),finalize) $@
 
-headers := $(wildcard */*.h)
+ifneq ($V,1)
+VERBOSE := @
+endif
 
 .PHONY: all test clean
 
-all: vgbc
+all: $(or $(DEFAULT_TARGETS),$(TARGETS))
+
+-include $(depfiles)
 
 clean:
 	rm -rf $(clean-objs)
 
 test: vgbc.test
-	@echo " ... run test $<"; \
-	./$< $(if $(V),-s,)
+	@echo " ... run test $<"
+	$(VERBOSE)./$< $(if $(V),-s)
 
-%.o: %.cpp $(headers)
-	@echo " ... build $@"; \
-	g++ $(CXX_FLAGS) -c -o $@ $<
+%.o: %.cpp
+	@echo " ... build $@"
+	$(VERBOSE)g++ $(CXX_FLAGS) -c -o $@ $<
 
-libemu.a: $(emu-objs)
-	@echo " ... pack $@"; \
-	ar -rc $@ $^
+define target_rule
+$(1): $$(modules_$(1))
+	@echo " ..." $$(or $$(msg_$(1)),$$(msg))
+	$$(VERBOSE)$$(or $$(cmd_$(1)),$$(cmd))
+endef
 
-vgbc: main.o libemu.a
-	@echo " ==> link $@"; \
-	g++ $(CXX_FLAGS) -o $@ $^
-
-vgbc.test: $(test-objs) libemu.a
-	@echo " ==> link $@"; \
-	g++ $(CXX_FLAGS) -o $@ $^
-
-vgbc.inspect: cartridge/inspector.o libemu.a
-	@echo " ==> link $@"; \
-	g++ $(CXX_FLAGS) -o $@ $^
+$(foreach t,$(TARGETS),$(eval $(call target_rule,$(t))))