dnl Process this file with autoconf to produce a configure script.
dnl ====================================================================
dnl
dnl     configure.in
dnl
dnl     Top-level configure script for eCos software.
dnl
dnl ====================================================================
dnl ####ECOSHOSTGPLCOPYRIGHTBEGIN####
dnl ----------------------------------------------------------------------------
dnl Copyright (C) 2002 Bart Veer
dnl Copyright (C) 1998, 1999, 2000, 2001 Red Hat, Inc.
dnl
dnl This file is part of the eCos host tools.
dnl
dnl This program is free software; you can redistribute it and/or modify it 
dnl under the terms of the GNU General Public License as published by the Free 
dnl Software Foundation; either version 2 of the License, or (at your option) 
dnl any later version.
dnl 
dnl This program is distributed in the hope that it will be useful, but WITHOUT 
dnl ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 
dnl FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for 
dnl more details.
dnl 
dnl You should have received a copy of the GNU General Public License along with
dnl this program; if not, write to the Free Software Foundation, Inc., 
dnl 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
dnl ----------------------------------------------------------------------------
dnl ####ECOSHOSTGPLCOPYRIGHTEND####
dnl ====================================================================
dnl#####DESCRIPTIONBEGIN####
dnl
dnl Author(s):	bartv
dnl Contact(s):	bartv
dnl Date:	1998/12/17
dnl Version:	0.01
dnl
dnl####DESCRIPTIONEND####
dnl ====================================================================

dnl eCos is a componentized architecture for deeply embedded systems.
dnl It requires a very different configuration system from typical
dnl autoconfiscated software such as the various GNU packages.
dnl
dnl The main eCos host-side software is autoconfiscated to some extent,
dnl in that the usual sequence of "configure;make;make install" will
dnl work under the right conditions. However it does not conform to
dnl the GNU coding standards in numerous ways, for example "make dist"
dnl will not work. The main eCos host-side software lives in the
dnl "host" subdirectory, and is built unconditionally.
dnl
dnl The eCos target-side software lives in the "packages" subdirectory,
dnl and is organized in numerous subdirectories corresponding to different
dnl packages and potentially different versions of each package. In the
dnl master repository managed by CVS there will only be one version of
dnl each package, "current", which simplifies things somewhat. Other
dnl repositories will not be quite so straightforward and require a
dnl suitable administration tool.
dnl
dnl The various eCos packages are not currently auto-confiscated.
dnl In particular building eCos requires the use of eCos configuration
dnl technology, not autoconf - there is simply no good way of handling
dnl a system as highly configurable as eCos using a few command-line
dnl options passed to "configure". There would also be serious confusion
dnl between host and target, especially when e.g. cross-compiling the
dnl host tools. However a possible future enhancement
dnl would involve making eCos releases via configure and make, thus
dnl allowing for a release process that combines building the various
dnl host-side tools such as gcc with creating eCos epk's for the various
dnl packages.
dnl
dnl A complication is that some of the eCos target-side packages also
dnl contain package-specific host-side support. For example the
dnl Linux synthetic target support uses special host-side software
dnl to provide I/O facilities: the architectural HAL package provdes
dnl generic support, the synthetic ethernet package extends this
dnl with ethernet support, and so on. Such package-specific host-side
dnl software does not belong in the main host subdirectory, that
dnl would make it very difficult to distribute new packages or
dnl new versions of a package. However keeping the code with the
dnl various packages makes building more complicated.
dnl
dnl   1) if the entire repository is managed by CVS or anoncvs, this
dnl      configure script will search the packages tree for any packages
dnl      that have host-side software that needs to be built -
dnl      specifically, that have a file "configure" inside a "host"
dnl      subdirectory in version "current" of a package.
dnl
dnl   2) if instead the repository contains additional packages
dnl      installed as epk's and managed by an administration tool then
dnl	 it is the responsibility of that tool to let the users build
dnl      and rebuild the host-side software as required, for whichever
dnl      host platform or platforms are being used. In other words
dnl      it is the responsibility of the admin tool to create a
dnl      suitable build directory and run "configure; make; make install",
dnl      usually as part of the installation process. Note that several
dnl	 versions of a package may be installed, and it is the
dnl	 responsibility of each package to take this into account
dnl      (although the configure macros are aware of this to some extent,
dnl      and will e.g. generate suitable install directory names).	 	 
dnl      Also note that the top-level configure script will not pick
dnl      up such packages because they will be versioned, i.e. the
dnl      test for current/host/configure will fail because the
dnl      version will not be "current".
dnl
dnl   3) as a special case it may be desirable to ship pre-built binaries
dnl      of some of the package-specific software. It is not clear
dnl	 just what would be the best way of shipping these - putting
dnl      them into the epk's would not be quite right because that would
dnl      make the epk's host-specific rather than generic.
dnl
dnl There is an unresolved problem with possible dependencies between
dnl packages, if e.g. the host-side of the synthetic ethernet package could
dnl only be built after the architectural synthetic target package.

dnl Some of the eCos documentation is generic and lives in the "doc"
dnl subdirectory. Other eCos documentation is package-specific and lives
dnl in the appropriate package directory. At present there is no support
dnl for building the documentation via configure and make, but such
dnl support may be added in future.
dnl
dnl There is a subdirectory acsupport containing various files such
dnl as config.guess and install.sh that are common. This also contains
dnl an acinclude.m4 file with various macros that are useful for
dnl eCos.

dnl Generic initialization.
AC_INIT(acsupport/config.guess)
AC_CONFIG_AUX_DIR(acsupport)
AC_CANONICAL_HOST
AM_INIT_AUTOMAKE(eCos,2.0,0)
AM_MAINTAINER_MODE
ECOS_CHECK_BUILD_ne_SRC

dnl Nothing actually gets built in this directory, so there should be no
dnl need to worry about compiler flags etc. Instead, the problem is
dnl figuring out what should actually get built.
dnl
dnl  1) the host subdirectory should always get built.
SUBDIRS="host"

dnl  2) any package which has a configure script in a
dnl     current/host subdirectory should also get built.
dnl
dnl     Searching the directory tree is currently done by shell globbing.
dnl     Invoking "find" with suitable arguments might be quicker, but
dnl     less portable. On some hosts there may be problems with environmental
dnl     limits if too many packages provide host-side software.
dnl
dnl     Currently there is no ordering of packages, so e.g. a device
dnl     driver's host-side support cannot depend on some HAL package
dnl     because the latter may not have been built and installed yet.
dnl     This is a good thing because packages are meant to be self-contained
dnl     whenever possible. Interaction between packages is typically handled
dnl     at the Tcl level at run-time, so there are no build-time complications.

PKGHOSTDIRS=""
FOUND_CONFIGURES=""
FOUND_CONFIGURES="${FOUND_CONFIGURES} ${srcdir}/packages/*/current/host/configure"
FOUND_CONFIGURES="${FOUND_CONFIGURES} ${srcdir}/packages/*/*/current/host/configure"
FOUND_CONFIGURES="${FOUND_CONFIGURES} ${srcdir}/packages/*/*/*/current/host/configure"
FOUND_CONFIGURES="${FOUND_CONFIGURES} ${srcdir}/packages/*/*/*/*/current/host/configure"
FOUND_CONFIGURES="${FOUND_CONFIGURES} ${srcdir}/packages/*/*/*/*/*/current/host/configure"
for configure in ${FOUND_CONFIGURES}; do
    if test -f ${configure}; then
        dnl A configure script has been found in the source tree.
        dnl First turn it into a directory, then replace the absolute path
        dnl with a relative one.
        hostdir=`dirname ${configure}`
        hostdir=`echo ${hostdir} | sed -e "s:^${srcdir}/::"`
        PKGHOSTDIRS="${PKGHOSTDIRS} ${hostdir}"
    fi
done

SUBDIRS="${SUBDIRS} ${PKGHOSTDIRS}"

dnl Because the eCos directory layout does not conform to GNU conventions
dnl it is necessary to create various levels of intermediate directories.
dnl This happens via config.status, prior to the recursion into the
dnl appropriate directories.
AC_OUTPUT_COMMANDS([${CONFIG_SHELL-/bin/sh} ${top_srcdir}/acsupport/mkinstalldirs ${REQUIRED_DIRS}],REQUIRED_DIRS="${SUBDIRS}")

AC_SUBST(SUBDIRS)
AC_CONFIG_SUBDIRS(${SUBDIRS})
AC_OUTPUT(Makefile)
