#!/bin/sh
# configure-dirs - generic configure for a source dir of subdirs.
#
################################################################
# Copyright (C) 2001 Tom Lord
# 
# See the file "COPYING" for further information about
# the copyright and warranty status of this work.
# 


set -e
if test x$objroot = x; then
  echo "ERROR: objroot not set in `pwd`" 1>&2
  exit 1
fi

if test x$srcroot = x; then
  echo "ERROR: srcroot not set in `pwd`" 1>&2
  exit 1
fi

if test x$srcdir = x; then
  echo "ERROR: srcdir not set in `pwd`" 1>&2
  exit 1
fi

if test x$prefix = x; then
  echo "ERROR: prefix not set in `pwd`" 1>&2
  exit 1
fi

if test x$config_shell = x; then
  echo "ERROR: config_shell not set in `pwd`" 1>&2
  exit 1
fi

here=`cd $srcdir; pwd`
base=`cd $srcroot ; pwd`

if test $here = $base; then
  thispath=
  export thispath
elif test x$thispath = x; then
  thispath=`basename $here`
else
  thispath=$thispath/`basename $here`
fi


# What subdirectories do we build?
# 
# Some subdirectories contain a file called "PLUGIN/REQ".
# 
# Some subdirectories contain a file called "PLUGIN/OPT".
# 
# Both kinds of file contain dependency lists suitable for "tsort".
# Each line is of the form:
#
#		prerequisit-dir		build-dir
# 
# which means that if "prerequisit-dir" is being compiled, it must be
# compiled before compiling "build-dir".
# 
# If a directory is named in a "PLUGIN/REQ" directory (either as a
# prerequisit or a build-dir), we MUST build that directory.  It is a
# "required directory".
# 
# If a directory is named in a "PLUGIN/OPT" directory (either as a
# prerequisit or a build-dir), we MIGHT build that directory.  It is
# an "optional directory".
# 
# If a directory is both optional and required, it is treated as a
# required directory.
# 
# If a directory has a subdirectory named "PLUGIN", we CAN build that
# directory.
# 
# If a required directory has no subdirectory called "PLUGIN", that is
# an error because we can not build that directory.
# 
# If an optional directory has no subdirectory called "PLUGIN", we
# don't build that optional subdirectory.  If an optinal directory has
# a "PLUGIN" subdirectory, we do build that directory.
# 
# To summarize, we build all required directories and also build all
# optional directories that have a subdirectory called "PLUGIN".
# However, if a required directory does not have a subdirectory called
# "PLUGIN", that is an error that prevents compiling anything.  We
# compute the lists of required and optional directories by invoking
# "tsort" on the files "$srcdir/*/PLUGIN/REQ" and
# "$srcdir/*/PLUGIN/OPT".
# 
# "Prerequisits" don't work like "make" dependencies.  If a make
# dependency prerequisit is missing, we can't build targets that
# depend on that prerequisit.  But if a configure prerequisit is
# missing, as long as the prerequisit is optional, we build the
# depending targets anyway.  In other words, suppose that "$dirA"
# is optional and "$dirB" is required, and "$dirA" is a prerequisit of
# "$dirB".  Also suppose that "$dirA" has no subdirectory called
# "PLUGIN".  In this case, we build "$dirB" anyway.
# 


# Compute the lists of optional and required directories, in
# the order in which they should be built.
# 
# Unfortunately, "tsort" exits with a 0 status even if cycles
# are found.  Ideally, this would be an error.
# 

here="`pwd`"
cd "$srcdir"

reqs=
opts=

for f in * ; do
  if test -d "$f" -a -d "$f/PLUGIN" ; then
    if test -r "$f/PLUGIN/REQ" ; then
      reqs="$f/PLUGIN/REQ $reqs"
    fi
    if test -r "$f/PLUGIN/OPT" ; then
      opts="$f/PLUGIN/OPT $opts"
    fi
  fi
done

one_line()
{
  printf "$*"
}

rm -f "$here/,,tsort-master"
touch "$here/,,tsort-master"

if test -z "$reqs" ; then
  req_subdirs=
else
  req_subdirs=`cat $reqs | tsort`
  req_subdirs=`one_line "$req_subdirs"`
  cat $reqs >> "$here/,,tsort-master"
fi

if test -z "$opts" ; then
  opt_subdirs=
else
  opt_subdirs=`cat $opts | tsort`
  opt_subdirs=`one_line "$opt_subdirs"`
  cat $opts >> "$here/,,tsort-master"
fi

# Make sure that all required directories have subdirectories called "PLUGIN".
# 
if test ! -z "$req_subdirs" ; then
  for d in $req_subdirs; do
    if test ! -d $srcdir/$d ; then
      echo "ERROR ($d): missing required directory" 1>&2
      exit 1
    fi
    if test ! -d $srcdir/$d/PLUGIN ; then
      echo "ERROR ($d): required directory with no PLUGIN directory" 1>&2
      exit 1
    fi
  done
fi

# Prune the list of optional subdirectories to remove those that do not
# have a subdirectory called "PLUGIN"
#

if test "x$opt_subdirs" != x ; then
  opt2=
  for d in $opt_subdirs; do
    if test ! -d $srcdir/$d/PLUGIN ; then
      echo "WARNING ($d): skipping optional directory (no PLUGIN directory found)" 1>&2
    else
      opt2="$opt2 $d"
    fi
  done
  opt_subdirs=$opt2
fi

cd "$here"

# Build a list of all the directories we will build, in the order
# they should be built.
#
rm -f ,,todo-dirs
touch ,,todo-dirs

if test ! -z "$req_subdirs" ; then
  for d in $req_subdirs ; do
    printf "%s\n" "$d" >> ,,todo-dirs
  done
fi

if test ! -z "$opt_subdirs" ; then
  for d in $opt_subdirs ; do
    printf "%s\n" "$d" >> ,,todo-dirs
  done
fi

rm -rf ,,master-order
tsort ,,tsort-master > ,,master-order

all_dirs=
for d in `cat ,,master-order` ; do
  if grep -q $d ,,todo-dirs ; then
    all_dirs="$all_dirs $d"
  fi
done

if test -z "$all_dirs" ; then
  printf "\\n"
  printf "WARNING: \\n"
  printf " in directory %s\\n" "$srcdir"
  printf " no subdirectories being built.\\n"
  printf "\\n"
else
  printf "\\n"
  printf "configuring subdirectories of %s\\n" "$srcdir"
  printf "in this order:\\n"
  printf "\\n"
  for d in $all_dirs; do
    printf "    %s\\n" "$d" 
  done
  printf "\\n"
fi

rm -f ,,todo-dirs
rm -f ,,tsort-master
rm -f ,,master-order

if test ! -z "$all_dirs" ; then
  # Run a generic "configure" script for each subdirectory.
  # 
  export srcroot
  export objroot
  export prefix
  export destdir
  export config_shell

  for f in $all_dirs; do
    printf "configuring %s...\n" "$f"

    mkdir -p $f

    cd $f
    srcdir=$srcdir/$f $srcroot/build-tools/scripts/configure-generic
    cd ..

  done
fi

# Generate the top-level "Makefile" from some computed
# variable definitions and the top-level "Makefile.in" in
# the source tree.
# 
# For GNU compatibility, and for debugging purposes, do
# this in two steps: first generate a "config.status"
# script which will create the Makefile, then invoke
# that script.
# 
printf "#!%s\\n\\n" "$config_shell" > config.status

cat >> config.status << EOF

  cat > Makefile <<-EOF2
	SHELL = $config_shell
	srcroot = $srcroot
	thispath = $thispath
	objroot = $objroot
	srcdir = $srcdir
	prefix = $prefix
	destdir = $destdir
	make-dirs = $all_dirs
	makefiles = $srcroot/build-tools/Makefiles
	vpath % $srcdir
	include \\\$(objroot)/Makefile-config.mk


EOF2

  cat $srcdir/Makefile.in >> Makefile

EOF

chmod ugo+x config.status

./config.status

# arch-tag: Tom Lord Tue Jul  1 16:25:54 2003 (scripts/configure-dirs)
#