From 870ae3efcc4380494f1f77676c2bdc9542814e2a Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@systemlinux.org>
Date: Wed, 4 Jun 2008 21:07:51 +0200
Subject: [PATCH] Makefile improvements.

Cleanups, add documentation and install target.
---
 Makefile | 122 +++++++++++++++++++++++++++++++++++++------------------
 1 file changed, 82 insertions(+), 40 deletions(-)

diff --git a/Makefile b/Makefile
index 8da3d1d..0a44111 100644
--- a/Makefile
+++ b/Makefile
@@ -1,71 +1,103 @@
+# where to install
+prefix := /usr/local
+libdir := $(prefix)/lib
+includedir := $(prefix)/include
+
+objects := osl.o fd.o rbtree.o sha1.o
+headers := osl.h
+
+INSTALL := install
+CC := gcc
+MKDIR := mkdir -p
+RM := rm -f
+LN := ln
+
+# libosl's versioning consists of three numbers. Let's call them x, y and z.
+# The way x, y and z are interpreted depends on the OS.
+x := 0
+y := 1
+z := 0
+
+# common flags
+CFLAGS += -Wno-sign-compare -g -Wunused -Wundef -W
+CFLAGS += -Wredundant-decls
+CFLAGS += -Os
+CFLAGS += -Wall
+CFLAGS += -Wuninitialized
+CFLAGS += -Wchar-subscripts
+CFLAGS += -Wformat-security
+CFLAGS += -Werror-implicit-function-declaration
+CFLAGS += -Wmissing-format-attribute
+CFLAGS += -Wunused-macros
+CFLAGS += -Wbad-function-cast
+CFLAGS += -fPIC
+CFLAGS += -fvisibility=hidden
+
 uname_s := $(shell uname -s 2>/dev/null || echo "UNKNOWN_OS")
 uname_rs := $(shell uname -rs)
 
-objects := osl.o fd.o rbtree.o sha1.o
-major_version := 0
-minor_version := 1
-patchlevel_version := 0
 libname := osl
+ifeq ($(uname_s),Linux)
+	# On Linux, the following conventions apply (see dhweeler's Program
+	# Library HOWTO):
+	#
+	# The soname has the prefix ``lib'', the name of the library, the
+	# phrase ``.so'', followed by a period and a version number that is
+	# incremented whenever the interface changes.
+	soname := lib$(libname).so.$(x)
 
+	# The real name adds to the soname a period, a minor number, another
+	# period, and the release number.
+	realname := $(soname).$(y).$(z)
 
-ifeq ($(uname_s),Linux)
-	dso_opts := --shared -Wl,-soname,libosl.so.$(major_version)
-	dso_filename :=lib$(libname).so.$(major_version).$(minor_version).$(patchlevel_version)
+	# In addition, there's the name that the compiler uses when requesting
+	# a library, (I'll call it the ``linker name''), which is simply the
+	# soname without any version number.
+	linkername := lib$(libname).so
+
+	LDFLAGS += --shared
+	LDFLAGS += -Wl,-soname,$(soname)
 	# disallow undefined symbols
 	LDFLAGS += -Wl,-z,defs
 endif
 ifeq ($(uname_s),Darwin)
 	# Darwin has its own idea on version numbers:
 	#
+	realname := lib$(libname).$(x).dylib
+	soname := $(realname)
+	linkername := lib$(libname).so
 	# The minor version number is an incremental number using the format
 	# X[.Y[.Z]]. To set the minor version number of a dynamic library, use
 	# the gcc -current_version option.
+	LDFLAGS += -current_version $(y).$(z)
 	#
 	# The compatibility version number of a library release specifies the
 	# earliest minor version of the clients linked against that release can
 	# use.
-	dso_opts := -dynamiclib -current_version $(minor_version).$(patchlevel_version) \
-		-compatibility_version $(minor_version).0 -fvisibility=hidden
-	dso_filename := lib$(libname).$(major_version).dylib
+	LDFLAGS += -compatibility_version $(y).0
+	LDFLAGS += -dynamiclib
 endif
 ifeq ($(uname_s),SunOS)
-	dso_opts := --shared -z text -z defs
-	dso_filename :=lib$(libname).so.$(major_version).$(minor_version).$(patchlevel_version)
+	# Solaris needs another set of flags
+	LDFLAGS += --shared
+	LDFLAGS += -z text
+	LDFLAGS += -z defs
+	realname := lib$(libname).so.$(major_version).$(minor_version).$(patchlevel_version)
 	CPPFLAGS += -I/opt/csw/include
 endif
-ifeq ($(uname_s),FreeBSD)
-	dso_opts := --shared -Wl,-soname,libosl.so.$(major_version)
-	dso_filename :=lib$(libname).so.$(major_version).$(minor_version).$(patchlevel_version)
-endif
-ifeq ($(uname_s),NetBSD)
-	dso_opts := --shared -Wl,-soname,libosl.so.$(major_version)
-	dso_filename :=lib$(libname).so.$(major_version).$(minor_version).$(patchlevel_version)
-endif
-all: $(dso_filename)
-
-DEBUG_CPPFLAGS += -Wno-sign-compare -g -Wunused -Wundef -W
-DEBUG_CPPFLAGS += -Wredundant-decls
-CPPFLAGS += -Os
-CPPFLAGS += -Wall
-CPPFLAGS += -Wuninitialized
-CPPFLAGS += -Wchar-subscripts
-CPPFLAGS += -Wformat-security
-CPPFLAGS += -Werror-implicit-function-declaration
-CPPFLAGS += -Wmissing-format-attribute
-CPPFLAGS += -Wunused-macros
-CPPFLAGS += -Wbad-function-cast
-CPPFLAGS += -fPIC
-CPPFLAGS += -fvisibility=hidden
+
+all: $(realname)
 
 Makefile.deps: $(wildcard *.c *.h)
-	gcc -MM -MG *.c > $@
+	$(CC) -MM -MG *.c > $@
 
 -include Makefile.deps
 
 %.o: %.c Makefile
-	$(CC) -c $(CPPFLAGS) $(DEBUG_CPPFLAGS) $<
-$(dso_filename): $(objects)
-	$(CC) $(dso_opts) -o $@ $(objects) $(LDFLAGS) -lcrypto
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $<
+
+$(realname): $(objects)
+	$(CC) $(LDFLAGS) -o $@ $(objects) $(LDFLAGS) -lcrypto
 
 osl_errors.h: errlist
 	sed -e 's/\([A-Z_]*\)	.*/	E_OSL_\1/' \
@@ -75,7 +107,17 @@ osl_errors.h: errlist
 
 errtab.h: errlist
 	sed -e 's/^\([A-Z_]*\)\s*\(.*\)/_S(E_OSL_\1, \2)/g' $< > $@
+
 osl.h: osl.h.in osl_errors.h
 	cat $^ > $@
 clean:
-	rm -f *.o $(dso_filename) osl.h osl_errors.h errtab.h
+	rm -f *.o $(realname) osl.h osl_errors.h errtab.h
+
+install: all
+	$(MKDIR) $(libdir) $(includedir)
+	$(RM) $(libdir)/$(linkername)
+	$(LN) -s $(libdir)/$(soname) $(libdir)/$(linkername)
+	$(INSTALL) -s -m 755 $(realname) $(libdir)
+	$(INSTALL) -m 644 $(headers) $(includedir)
+
+.PHONY: all clean install
-- 
2.39.5