From 6af65a44a3b6199f492f8f9fc81576920c7a0707 Mon Sep 17 00:00:00 2001
From: minhqdao <hello@minhdao.de>
Date: Mon, 4 Mar 2024 02:08:51 +0300
Subject: [PATCH] Add support for shared libraries

---
 .gitignore |   2 +
 Makefile   | 108 ++++++++++++++++++++++++++++++++---------------------
 2 files changed, 68 insertions(+), 42 deletions(-)

diff --git a/.gitignore b/.gitignore
index 4c27c27..1cab72c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,5 @@ build
 
 # Locally generated libraries
 *.a
+*.so
+*.dylib
diff --git a/Makefile b/Makefile
index 70b2022..53a6bb5 100644
--- a/Makefile
+++ b/Makefile
@@ -1,62 +1,86 @@
 .POSIX:
 .SUFFIXES:
-.PHONY: all test clean
-
-FC = gfortran
-FFLAGS = -O2
-AR = ar
-ARFLAGS = rcs
-
-NAME = version-f
-STATIC = lib$(NAME).a
-
-SRCDIR = src
-TESTDIR = test
-EXMPLDIR = example
-BUILDDIR = build/Makefile
-MODDIR = $(BUILDDIR)/mod
-OBJDIR = $(BUILDDIR)/obj
-EXEDIR = $(BUILDDIR)/exe
-
-SRCS = $(wildcard $(SRCDIR)/*.f90)
-TESTSRCS = $(wildcard $(TESTDIR)/*.f90)
-EXMPLSRCS = $(wildcard $(EXMPLDIR)/*.f90)
-OBJS = $(patsubst $(SRCDIR)/%.f90,$(OBJDIR)/%.o,$(SRCS))
-TESTEXES = $(patsubst $(TESTDIR)/%.f90,$(EXEDIR)/%.out,$(TESTSRCS))
-EXMPLEXES = $(patsubst $(EXMPLDIR)/%.f90,$(EXEDIR)/%.out,$(EXMPLSRCS))
+.PHONY: all static shared test clean
+
+FC := gfortran
+FFLAGS := -O2
+AR := ar
+ARFLAGS := rcs
+
+NAME := version-f
+STATIC := lib$(NAME).a
+
+ifeq ($(shell uname), Linux)
+    SHARED := lib$(NAME).so
+else ifeq ($(shell uname), Darwin)
+    SHARED := lib$(NAME).dylib
+endif
+
+SRCDIR := src
+TESTDIR := test
+EXMPLDIR := example
+BUILDDIR := build/Makefile
+MODDIR := $(BUILDDIR)/mod
+OBJDIR := $(BUILDDIR)/obj
+EXEDIRSTATIC := $(BUILDDIR)/exe/static
+EXEDIRSHARED := $(BUILDDIR)/exe/shared
 
 ifeq ($(FC),nvfortran)
-	MODOUT = -module $(MODDIR)
+	MODOUT := -module $(MODDIR)
 else
-	MODOUT = -J$(MODDIR)
+	MODOUT := -J$(MODDIR)
 endif
 
 ifeq ($(FC),nvfortran)
-	MODIN = -module $(MODDIR)
+	MODIN := -module $(MODDIR)
 else
-	MODIN = -I$(MODDIR)
+	MODIN := -I$(MODDIR)
 endif
 
-all: $(STATIC)
+SRCS := $(wildcard $(SRCDIR)/*.f90)
+TESTSRCS := $(wildcard $(TESTDIR)/*.f90)
+EXMPLSRCS := $(wildcard $(EXMPLDIR)/*.f90)
+OBJS := $(patsubst $(SRCDIR)/%.f90,$(OBJDIR)/%.o,$(SRCS))
+TESTEXESSTATIC := $(patsubst $(TESTDIR)/%.f90,$(EXEDIRSTATIC)/%.out,$(TESTSRCS))
+TESTEXESSHARED := $(patsubst $(TESTDIR)/%.f90,$(EXEDIRSHARED)/%.out,$(TESTSRCS))
+EXMPLEXESSTATIC := $(patsubst $(EXMPLDIR)/%.f90,$(EXEDIRSTATIC)/%.out,$(EXMPLSRCS))
+EXMPLEXESSHARED := $(patsubst $(EXMPLDIR)/%.f90,$(EXEDIRSHARED)/%.out,$(EXMPLSRCS))
+
+all: $(STATIC) $(SHARED)
+static: $(STATIC)
+shared: $(SHARED)
 
 $(OBJDIR)/%.o: $(SRCDIR)/%.f90
-		mkdir -p $(MODDIR) $(OBJDIR)
-		$(FC) $(FFLAGS) $(MODOUT) -c $< -o $@
+	mkdir -p $(MODDIR) $(OBJDIR)
+	$(FC) $(FFLAGS) $(MODOUT) -c $< -o $@
 
 $(STATIC): $(OBJS)
-		$(AR) $(ARFLAGS) $@ $(OBJS)
+	$(AR) $(ARFLAGS) $@ $(OBJS)
+
+$(SHARED): $(SRCS)
+	mkdir -p $(MODDIR)
+	$(FC) $(FFLAGS) -fpic -shared $(MODOUT) -o $@ $<
+
+$(EXEDIRSTATIC)/%.out: $(TESTDIR)/%.f90 $(STATIC)
+	mkdir -p $(EXEDIRSTATIC)
+	$(FC) $(FFLAGS) $< $(MODIN) -o $@ $(STATIC)
+
+$(EXEDIRSTATIC)/%.out: $(EXMPLDIR)/%.f90 $(STATIC)
+	mkdir -p $(EXEDIRSTATIC)
+	$(FC) $(FFLAGS) $< $(MODIN) -o $@ $(STATIC)
 
-$(EXEDIR)/%.out: $(TESTDIR)/%.f90 $(STATIC)
-		mkdir -p $(EXEDIR)
-		$(FC) $(FFLAGS) $< $(MODIN) -o $@ $(STATIC)
+$(EXEDIRSHARED)/%.out: $(TESTDIR)/%.f90 $(SHARED)
+	mkdir -p $(EXEDIRSHARED)
+	$(FC) $(FFLAGS) $< $(MODIN) -o $@ $(SHARED)
 
-$(EXEDIR)/%.out: $(EXMPLDIR)/%.f90 $(STATIC)
-		mkdir -p $(EXEDIR)
-		$(FC) $(FFLAGS) $< $(MODIN) -o $@ $(STATIC)
+$(EXEDIRSHARED)/%.out: $(EXMPLDIR)/%.f90 $(SHARED)
+	mkdir -p $(EXEDIRSHARED)
+	$(FC) $(FFLAGS) $< $(MODIN) -o $@ $(SHARED)
 
-test: $(TESTEXES) $(EXMPLEXES)
-		@for f in $(TESTEXES) $(EXMPLEXES); do $$f; done
+test: $(TESTEXESSTATIC) $(TESTEXESSHARED) $(EXMPLEXESSTATIC) $(EXMPLEXESSHARED)
+	@for f in $^; do $$f; done
 
 clean:
-		rm -rf $(BUILDDIR)
-		rm -f $(STATIC)
+	rm -rf $(BUILDDIR)
+	rm -f $(STATIC)
+	rm -f $(SHARED)