Makefile: add shared lib

Makefile/Makefile

@@ -12,7 +12,15 @@ LDLIBS = #$(pkg-config --libs sdl)
 
 bin = main
 cxxbin = cxxmain
-sources = $(wildcard *.c)
+lib = libexample.so
+
+#Will be compiled with -fpic
+lib_src = lib.c
+lib_obj = $(lib_src:%.c=%.o)
+lib_dep = $(lib_src:%.c=%.d)
+$(info $$lib_obj is ${lib_obj})
+
+sources = $(filter-out $(lib_src), $(wildcard *.c))
 objects = $(sources:%.c=%.o)
 depends = $(sources:%.c=%.d)
 
@@ -30,11 +38,18 @@ $(cxxbin) : $(cxx_objects)
 $(cxxbin):
 	$(LINK.cc) $^ $(LDLIBS) -o $@
 
+$(lib): CFLAGS += -fpic
+$(lib): $(lib_obj)
+
+%.so:
+	$(LINK.c) -shared $^ $(LDLIBS) -o $@
+
 .PHONY: clean
 clean:
-	$(RM) $(bin) $(objects) $(depends) $(cxxbin) $(cxx_objects) $(cxx_depends)
+	$(RM) $(bin) $(objects) $(depends) $(cxxbin) $(cxx_objects) $(cxx_depends) $(lib) $(lib_obj) $(lib_dep)
 
 ifneq ($(MAKECMDGOALS),clean)
 -include $(depends)
 -include $(cxx_depends)
+-include $(lib_dep)
 endif