Makefile: Build dynstr also as a shared library

.gitignore

@@ -1,3 +1,5 @@
 *.o
 *.obj
 *.a
+*.so
+*.so.*

Makefile

@@ -17,27 +17,41 @@
 PREFIX = /usr/local
 DST = $(PREFIX)/lib
 PC_DST = $(DST)/pkgconfig
-PROJECT = libdynstr.a
-CFLAGS = -Iinclude
+PROJECT = libdynstr
+MAJOR_VERSION = 0
+MINOR_VERSION = 1
+PATCH_VERSION = 0
+VERSION = $(MAJOR_VERSION).$(MINOR_VERSION).$(PATCH_VERSION)
+PROJECT_A = $(PROJECT).a
+PROJECT_SO = $(PROJECT).so.$(VERSION)
+PROJECT_SO_FQ = $(PROJECT).so.$(MAJOR_VERSION)
+PROJECT_SO_NV = $(PROJECT).so
+CFLAGS = -Iinclude -fPIC
+LDFLAGS = -shared
 DEPS = \
 	dynstr.o
 
-all: $(PROJECT)
+all: $(PROJECT_A) $(PROJECT_SO)
 
-install: $(PROJECT) $(PC_DST)/dynstr.pc
+install: all $(PC_DST)/dynstr.pc
 	mkdir -p $(PREFIX)/include
 	cp include/dynstr.h $(PREFIX)/include
 	chmod 0644 $(PREFIX)/include/dynstr.h
 	mkdir -p $(DST)
-	cp $(PROJECT) $(DST)
-	chmod 0755 $(DST)/$(PROJECT)
+	cp $(PROJECT_A) $(PROJECT_SO) $(DST)
+	chmod 0755 $(DST)/$(PROJECT_A) $(DST)/$(PROJECT_SO)
+	ln -fs $(DST)/$(PROJECT_SO) $(DST)/$(PROJECT_SO_FQ)
+	ln -fs $(DST)/$(PROJECT_SO) $(DST)/$(PROJECT_SO_NV)
 
 clean:
 	rm -f $(DEPS)
 
-$(PROJECT): $(DEPS)
+$(PROJECT_A): $(DEPS)
 	$(AR) $(ARFLAGS) $@ $(DEPS)
 
+$(PROJECT_SO): $(DEPS)
+	$(CC) $(LDFLAGS) $(DEPS) -o $@
+
 $(PC_DST)/dynstr.pc: dynstr.pc
 	mkdir -p $(PC_DST)
 	sed -e 's,/usr/local,$(PREFIX),' $< > $@