#! /bin/sh

# Shell script to build Makefile in a build directory. It must be called
# from inside the directory. It does its own checking of when to rebuild; it
# just got too horrendous to get it right in "make", because of the optionally
# existing configuration files.
#
# Copyright (c) The Exim Maintainers 2016


# First off, get the OS type, and check that there is a make file for it.

ostype=`../scripts/os-type -generic` || exit 1

if [ ! -r ../OS/Makefile-$ostype ] ; then
  echo ""
  echo "*** Sorry - operating system $ostype is not supported"
  echo "*** See OS/Makefile-* for supported systems" 1>&2
  echo ""
  exit 1
fi

# We also need the architecture type, in order to test for any architecture-
# specific configuration files.

archtype=`../scripts/arch-type` || exit 1

# Now test for either the non-existence of Makefile, or for any of its
# components being newer. Note that the "newer" script gives the right
# answer (for our purposes) when the first file is non-existent.

editme=../Local/Makefile
rebuild=yes

if [ -f Makefile ] ; then
  rebuild=no
  if ../scripts/newer $editme Makefile || \
     ../scripts/newer $editme-$ostype Makefile || \
     ../scripts/newer $editme-$archtype Makefile || \
     ../scripts/newer $editme-$ostype-$archtype Makefile || \
     ../scripts/newer ../scripts/Configure-Makefile Makefile || \
     ../scripts/newer ../OS/Makefile-Base Makefile || \
     ../scripts/newer ../OS/Makefile-Default Makefile
  then
    rebuild=yes
  fi
fi

# If the "build" variable is set it means that a build name was explicitly
# given. Arrange to pick up a build-specific configuration file.

if [ "X$build" != "X" ] ; then
  mfb=Local/Makefile-$build
  if ../scripts/newer $editme-$build Makefile ; then
    rebuild=yes
  fi
else
  mfb=
fi


# If Makefile is up-to-date, no need to rebuild it.

if [ $rebuild = no ] ; then
  echo "\`Makefile' is up to date."
  echo " "
  exit
fi

# Makefile needs to be rebuilt in the current directory by joining
# the generic default makefile, the OS base makefile, and then local
# generic, OS-specific, architecture-specific, and OS+architecture-specific
# makefiles, if they exist. These files all contain macro definitions, with
# later definitions overriding earlier ones. Make a temporary file first, in
# case things go wrong. A second temporary is needed for sorting out the
# default Perl stuff. Use short macro names to save typing.

mf=Makefile
mft=$mf-t
mftt=$mf-tt
mftepcp=$mf-tepcp
mftepcp2=$mf-tepcp2

look_mf=lookups/Makefile
look_mf_pre=${look_mf}.predynamic
look_mf_post=${look_mf}.postdynamic

# Ensure the temporary does not exist and start the new one by setting
# the OSTYPE and ARCHTYPE variables.

rm -f $mft $mftt $mftepcp $mftepcp2 $look_mf-t
(echo "OSTYPE=$ostype"; echo "ARCHTYPE=$archtype"; echo "") > $mft || exit 1

# Now concatenate the files to the temporary file. Copy the files using sed to
# remove comments, blank lines, and trailing white space.

# BEWARE: a tab character is needed in the sed command below. It has had
# a nasty tendency to get lost in the past, causing a problem if a tab has
# actually been present in one of the files. Use a variable to hold a space
# and a tab to keep the tab in one place.

st='	 '

for f in OS/Makefile-Default \
         OS/Makefile-$ostype \
         Local/Makefile \
         Local/Makefile-$ostype \
         Local/Makefile-$archtype \
         Local/Makefile-$ostype-$archtype \
         $mfb
do   if test -r ../$f
     then   echo "# From $f"
            sed "/^#/d;/^[$st]*\$/d;s/[$st]*\$//" ../$f || exit 1
            echo "# End of $f"
            echo ""
     fi
done \
     | sed 's/^TMPDIR=/EXIM_&/' \
     >> $mft || exit 1

# handle PKG_CONFIG_PATH because we need it in our env, and we want to handle
# wildcards; note that this logic means all setting _appends_ values, never
# replacing; if that's a problem, we can revisit.
sed -n "s/^[$st]*PKG_CONFIG_PATH[$st]*[+]*=[$st]*//p" $mft | \
  sed "s/[$st]*\$//" >> $mftepcp
if test -s ./$mftepcp
then
  # expand any wildcards and strip spaces, to make it a real PATH-like variable
  ( IFS=":${IFS-$st}"; for P in `cat ./$mftepcp`; do echo "$P"; done ) | xargs | sed "s/[$st]/:/g" >./$mftepcp2
  sed "s/^/PKG_CONFIG_PATH='/" < ./$mftepcp2 | sed "s/\$/'/" > ./$mftepcp
  . ./$mftepcp
  export PKG_CONFIG_PATH
  egrep -v "^[$st]*PKG_CONFIG_PATH[$st]*=" ./$mft > ./$mftt
  rm -f ./$mft
  (
    echo "# Collapsed PKG_CONFIG_PATH in build-prep:"
    sed "s/'//g" ./$mftepcp
    echo "# End of collapsed PKG_CONFIG_PATH"
    echo ""
    cat ./$mftt
  ) > ./$mft
  rm -f ./$mftt
fi
rm -f ./$mftepcp ./$mftepcp2

# handle pkg-config
# beware portability of extended regexps with sed.
egrep "^[$st]*(AUTH|LOOKUP)_[A-Z0-9_]*[$st]*=[$st]*" $mft | \
  sed "s/[$st]*=/='/" | \
  sed "s/\$/'/" > $mftt
egrep "^[$st]*((USE_(OPENSSL|GNUTLS)_PC)|SUPPORT_TLS|USE_GNUTLS|PCRE_CONFIG|AVOID_GNUTLS_PKCS11)[$st]*=[$st]*" $mft | \
  sed "s/[$st]*=/='/" | \
  sed "s/\$/'/" >> $mftt
if test -s $mftt
then
  (
  echo "# pkg-config fixups"
  . ./$mftt
  for var in `cut -d = -f 1 < $mftt`; do
    case $var in

      USE_*_PC)
        eval "pc_value=\"\$$var\""
        need_this=''
        need_core=''
        if [ ".$SUPPORT_TLS" = "." ]; then
          # no TLS, not referencing
          true
        elif [ ".$var" = ".USE_GNUTLS_PC" ] && [ ".$USE_GNUTLS" != "." ]; then
          need_this=t
          need_core="gnutls-special"
        elif [ ".$var" = ".USE_OPENSSL_PC" ] && [ ".$USE_GNUTLS" = "." ]; then
          need_this=t
          need_core=t
        fi
        if [ ".$need_this" != "." ]; then
          tls_include=`pkg-config --cflags $pc_value`
          if [ $? -ne 0 ]; then
            echo >&2 "*** Missing pkg-config for package $pc_value (for Exim $var build option)"
            exit 1
          fi
          tls_libs=`pkg-config --libs $pc_value`
          echo "TLS_INCLUDE=$tls_include"
          echo "TLS_LIBS=$tls_libs"
          # With hash.h pulling crypto into the core, we need to also handle that
          if [ ".$need_this" = ".t" ]; then
            echo "CFLAGS += $tls_include"
            echo "LDFLAGS += $tls_libs"
          elif [ ".$need_this" = ".gnutls-special" ]; then
            if pkg-config --atleast-version=2.10 gnutls ; then
              echo "CFLAGS += $tls_include"
              echo "LDFLAGS += $tls_libs"
            else
              echo "CFLAGS += `libgcrypt-config --cflags`"
              echo "LDFLAGS += `libgcrypt-config --libs`"
            fi
          fi
        fi
        ;;

      *_PC)
        eval "pc_value=\"\$$var\""
        base=`echo $var | sed 's/_PC$//'`
        eval "basevalue=\"\$$base\""
        if [ ".$basevalue" = "." ]; then
          # not pulling in this module, _PC defined as default? Ignore
          true
        elif [ $basevalue = 2 ]; then
          # module; handled in scripts/lookups-Makefile
          true
        else
          # main binary
          cflags=`pkg-config --cflags $pc_value`
          if [ $? -ne 0 ]; then
            echo >&2 "*** Missing pkg-config for package $pc_value (for Exim $var build option)"
            exit 1
          fi
          libs=`pkg-config --libs $pc_value`
          if [ "$var" != "${var#LOOKUP_}" ]; then
            echo "LOOKUP_INCLUDE += $cflags"
            echo "LOOKUP_LIBS += $libs"
          elif [ "$var" != "${var#AUTH_}" ]; then
            echo "CFLAGS += $cflags"
            echo "AUTH_LIBS += $libs"
          else
            echo >&2 "Don't know how to handle pkg-config for $var"
          fi
        fi
        ;;

      PCRE_CONFIG)
        case $PCRE_CONFIG in
          yes|YES|y|Y)
            cflags=`pcre-config --cflags`
            if [ $? -ne 0 ]; then
              echo >&2 "*** Missing pcre-config for regular expression support"
              exit 1
            fi
            libs=`pcre-config --libs`
            if [ ".$cflags" != "." ]; then
              echo "INCLUDE += $cflags"
            fi
            echo "PCRE_LIBS=$libs"
            ;;
        esac
        ;;

      AVOID_GNUTLS_PKCS11)
        echo "$var=yes"
        ;;

    esac
  done
  echo "# End of pkg-config fixups"
  echo
  ) >> $mft
  subexit=$?
  if [ $subexit -ne 0 ]; then
    exit $subexit
  fi
fi
rm -f $mftt

# make the lookups Makefile with the definitions
# the auxiliary script generates $look_mf_post from $look_mf_pre

cp ../src/lookups/Makefile $look_mf_pre
../scripts/lookups-Makefile

# See if there is a definition of EXIM_PERL in what we have built so far.
# If so, run Perl to find the default values for PERL_CC, PERL_CCOPTS,
# and PERL_LIBS. These need to be put at the top of the Makefile, so we rename
# what we have so far and then copy it afterwards. Use the value of PERL_COMMAND
# if it has been defined.

EXIM_PERL=`grep EXIM_PERL $mft`

PERL_COMMAND=`grep PERL_COMMAND $mft | sed -e "\\$!d;s/^[$st]*PERL_COMMAND[$st]*=[$st]*//"`
if [ "${PERL_COMMAND}" = "" ] ; then
  PERL_COMMAND='perl'
fi

if [ "${EXIM_PERL}" != "" ] ; then
  testperl=`$PERL_COMMAND --version`
  if [ "$testperl" = "" ] ; then
    echo "*** EXIM_PERL is set, but '$PERL_COMMAND --version' failed"
    exit 1
  fi

  EXTUTILS_EMBED_NOT_INSTALLED=`$PERL_COMMAND -MExtUtils::Embed -e ";" 2>&1`
  if [ "${EXTUTILS_EMBED_NOT_INSTALLED}" != "" ] ; then
    echo "Please install ExtUtils::Embed for $PERL_COMMAND"
    exit 1;
  fi

  mv $mft $mftt
  echo "PERL_CC=`$PERL_COMMAND -MConfig -e 'print $Config{cc}'`" >>$mft
  echo "PERL_CCOPTS=`$PERL_COMMAND -MExtUtils::Embed -e ccopts`" >>$mft
  echo "PERL_LIBS=`$PERL_COMMAND -MExtUtils::Embed -e ldopts`" >>$mft
  echo "" >>$mft
  cat $mftt >> $mft
  rm -f $mftt
fi

# Record the build variable in the Makefile.

echo "build=$build" >>$mft
echo "" >>$mft

# Finally, join on the generic base make file, which contains the actual
# rules and stuff.

echo "# From ../OS/Makefile-Base" >> $mft
cat ../OS/Makefile-Base >> $mft || exit 1

# If the new makefile is the same as the existing one, say so, and just
# update the timestamp. Otherwise remove the old and install the new.

if      [ -s $mf ] && cmp -s $mft $mf && [ -s $look_mf ] && cmp -s $look_mf_post $look_mf
then    echo ">>> rebuilt $mf unchanged"
        echo " "
        touch $mf || exit
        rm -f $mft $look_mf_pre $look_mf_post
elif    rm -f $mf $look_mf $look_mf_pre
        mv $mft $mf
	mv $look_mf_post $look_mf
then    echo ">>> New $mf & $look_mf installed"
        echo '>>> Use "make makefile" if you need to force rebuilding of the makefile'
        echo " "
else    echo " "
        echo "*** Failed to install $mf - see $mft"
	echo "    (or $look_mft)"
        echo " "
        exit 1;
fi

# vim: set ft=sh :
# End of Configure-Makefile