151 lines
6.5 KiB
Makefile
151 lines
6.5 KiB
Makefile
# $Id: Makefile.am,v 1.16 2008/03/20 19:02:38 karl Exp $
|
|
#
|
|
# Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008
|
|
# Rocky Bernstein <rocky@gnu.org>
|
|
#
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
########################################################
|
|
# Things to make the libiso9660 library
|
|
########################################################
|
|
#
|
|
# From libtool documentation amended with guidance from N. Boullis:
|
|
#
|
|
# 1. Start with version information of `0:0:0' for each libtool library.
|
|
#
|
|
# 2. It is probably not a good idea to update the version information
|
|
# several times between public releases, but rather once per public
|
|
# release. (This seems to be more an aesthetic consideration than
|
|
# a hard technical one.)
|
|
#
|
|
# 3. If the library source code has changed at all since the last
|
|
# update, then increment REVISION (`C:R:A' becomes `C:R+1:A').
|
|
#
|
|
# 4. If any interfaces have been added, removed, or changed since the
|
|
# last update, increment CURRENT, and set REVISION to 0.
|
|
#
|
|
# 5. If any interfaces have been added since the last public release,
|
|
# then increment AGE.
|
|
#
|
|
# 6. If any interfaces have been removed or changed since the last
|
|
# public release, then set AGE to 0. A changed interface means an
|
|
# incompatibility with previous versions.
|
|
|
|
libiso9660_la_CURRENT = 6
|
|
libiso9660_la_REVISION = 0
|
|
libiso9660_la_AGE = 1
|
|
|
|
EXTRA_DIST = libiso9660.sym
|
|
|
|
noinst_HEADERS = iso9660_private.h
|
|
|
|
lib_LTLIBRARIES = libiso9660.la
|
|
|
|
if ENABLE_ROCK
|
|
rock_src = rock.c
|
|
else
|
|
rock_src =
|
|
endif
|
|
|
|
libiso9660_la_SOURCES = \
|
|
iso9660.c \
|
|
iso9660_private.h \
|
|
iso9660_fs.c \
|
|
$(rock_src) \
|
|
xa.c
|
|
|
|
libiso9660_la_LIBADD = @LIBCDIO_LIBS@
|
|
libiso9660_la_ldflags = -version-info $(libiso9660_la_CURRENT):$(libiso9660_la_REVISION):$(libiso9660_la_AGE)
|
|
libiso9660_la_dependencies = libcdio.la
|
|
|
|
INCLUDES = $(LIBCDIO_CFLAGS)
|
|
|
|
########################################################
|
|
# Things to version the symbols in the libraries
|
|
########################################################
|
|
|
|
# An explanation of the versioning problem from Nicolas Boullis and
|
|
# the versioned symbol solution he uses below...
|
|
#
|
|
# Currently, libvcdinfo uses the cdio_open function from libcdio.
|
|
# Let's imagine a program foobar that uses both the vcdinfo_open
|
|
# function from libvcdinfo and the cdio_open function from libcdio.
|
|
|
|
# Currently, libcdio has SONAME libcdio.so.0, libvcdinfo has SONAME
|
|
# libvcdinfo.so.0 and requires libcdio.so.0, and foobar requires both
|
|
# libvcdinfo.so.0 and libcdio.so.0. Everything looks fine.
|
|
#
|
|
# Now, for some reason, you decide to change the cdio_open function.
|
|
# That's your right, but you have to bump the CURRENT version and (if I
|
|
# understand it correctly, athough this is not that clear in libtool's
|
|
# documentation) set the AGE to 0. Anyway, this bumps the SONAME, which is
|
|
# sane since the interface changes incompatibly.
|
|
|
|
# Now, you have a new libcdio with SONAME libcdio.so.1. But libvcdinfo and
|
|
# foobar still require libcdio.so.0. Everything is still fine.
|
|
|
|
# Now, after some minor changes, the author of foobar recompiles foobar.
|
|
# Then, foobar now requires libvcdinfo.so.0 and libcdio.so.1. And foobar
|
|
# now segfaults...
|
|
|
|
# What is happening? When you run foobar, if brings both libvcdinfo.so.0
|
|
# and libcdio.so.1, but libvcdinfo.so.0 also brings libcdio.so.0. So you
|
|
# have both libcdio.so.0 and libcdio.so.1 that bring their symbols to the
|
|
# global namespace. Hence, you have to incompatible versions of the
|
|
# cdio_open function in the name space. When foobar calls cdio_open, it
|
|
# may choose the wrong function, and segfaults...
|
|
|
|
# With versioned symbols, the cdio_open function from libcdio.so.0 may be
|
|
# known as (something that looks like) cdio_open@@CDIO_0. An the cdio_open
|
|
# function from libcdio.so.1 as cdio_open@@CDIO_1. Both versions of
|
|
# libcdio would still be brought in by the most recent foobar, but foobar
|
|
# (and libvcdinfo) know which versioned function to use and then use the
|
|
# good one.
|
|
|
|
|
|
# This is some simple versioning where every symbol is versioned with
|
|
# something that looks like the SONAME of the library. More complex (and
|
|
# better) versioning is possible; it is for example what is used by glibc.
|
|
# But good complex versioning is something that requires much more
|
|
# work...
|
|
|
|
|
|
# The below is a impliments symbol versioning. First of all, I
|
|
# compute MAJOR as CURENT - AGE; that is what is used within libtool
|
|
# (at least on GNU/Linux systems) for the number in the SONAME. The
|
|
# nm command gives the list of symbols known in each of the object
|
|
# files that will be part of the shared library. And the sed command
|
|
# extracts from this list those symbols that will be shared. (This sed
|
|
# command comes from libtool.)
|
|
|
|
libiso9660_la_MAJOR = $(shell expr $(libiso9660_la_CURRENT) - $(libiso9660_la_AGE))
|
|
if BUILD_VERSIONED_LIBS
|
|
libiso9660_la_LDFLAGS = $(libiso9660_la_ldflags) -Wl,--version-script=libiso9660.la.ver
|
|
libiso9660_la_DEPENDENCIES = $(libcdio9660_la_dependencies) libiso9660.la.ver
|
|
|
|
libiso9660.la.ver: $(libiso9660_la_OBJECTS) $(srcdir)/libiso9660.sym
|
|
echo 'ISO9660_$(libiso9660_la_MAJOR) {' > $@
|
|
objs=`for obj in $(libiso9660_la_OBJECTS); do sed -ne "s/^pic_object='\(.*\)'$$/\1/p" $$obj; done`;
|
|
if test -n "$$objs" ; then \
|
|
nm $${objs} | sed -n -e 's/^.*[ ][ABCDGIRSTW][ABCDGIRSTW]*[ ][ ]*\([_A-Za-z][_A-Za-z0-9]*\)$$/\1/p' | sort -u | { first=true; while read symbol; do if grep -q "^$${symbol}\$$" $(srcdir)/libiso9660.sym; then if test $$first = true; then echo " global:"; first=false; fi; echo " $${symbol};"; fi; done; } >> $@; \
|
|
nm $${objs} | sed -n -e 's/^.*[ ][ABCDGIRSTW][ABCDGIRSTW]*[ ][ ]*\([_A-Za-z][_A-Za-z0-9]*\)$$/\1/p' | sort -u | { first=true; while read symbol; do if grep -q "^$${symbol}\$$" $(srcdir)/libiso9660.sym; then :; else if test $$first = true; then echo " local:"; first=false; fi; echo " $${symbol};"; fi; done; } >> $@; \
|
|
fi
|
|
echo '};' >> $@
|
|
|
|
MOSTLYCLEANFILES = libiso9660.la.ver
|
|
else
|
|
libiso9660_la_LDFLAGS = $(libiso9660_la_ldflags)
|
|
libiso9660_la_DEPENDENCIES = $(libcdio9660_la_dependencies)
|
|
endif
|