#!/bin/sh -e

#####################################################
# this configure-script searches for the needed includes
# and libraries.
#
# it is MUCH faster, smaller as GNU autoconf and does what I want. :-)
# if you have a very unusual setup or you are cross-compiling
# you can edit "Local.mak" to fit your needs and to reflect your setup
# 
# The Makefiles should support parallel builds.
#
#######################################################

version=0.2.0
DIRS=""

for dir in $@; do
  DIRS="$DIRS `cd $dir; pwd`"
done
DIRS="$DIRS /usr /usr/local"
echo $DIRS

CF=""
LIBS=
LDIRS=

err() {
  echo
  echo ERROR: $1
  echo 
  err_occ=Y
}

#adds an includedir to $CF
add_include() {
  for _dir in -I/usr/include ${CF}; do
    if test "-I$1" = "${_dir}"; then
      return 0
    fi
  done
 
  CF="${CF} -I$1"
}

add_lib() {
  LIBS="$LIBS -l$2"
  for _libs in -L/usr/lib ${LDIRS}; do
    if test "-L$1" = "${_libs}"; then
      return 0
    fi
  done

  LDIRS="${LDIRS} -L$1"
}

# check for includes
search_includes() {
  for dir in ${DIRS};  do
    for incdir in /include ""; do
      for dbn in "" ${subdirs}; do
        if test -r ${dir}${incdir}${dbn}/$1; then
          add_include ${dir}${incdir}${dbn}
          echo Found: $1 at ${dir}${incdir}${dbn}
          return 0
        fi
      done
    done
  done
  return 1
}

# check for libs
search_lib() {
  for dbn in $@; do
    for dir in ${DIRS};  do
      for libdir in /lib "";  do
        for suffix in so dylib obj a; do
          if test -r ${dir}${libdir}/lib${dbn}.${suffix}; then
            add_lib ${dir}${libdir} ${dbn};
	    echo Found: lib${dbn}.${suffix} at ${dir}/lib
            return 0
	  fi
        done
      done
    done
  done
  return 1
}
 

######################## e2fsprogs
subdirs="/lib"
search_includes ext2fs/ext2fs.h || err "Ext2progs header files were not found (ex2fs.h)"
search_includes e2p/e2p.h || err "Ext2progs header files were not found (e2p.h)"
search_lib ext2fs && \
search_lib com_err || \
	err "The ext2progs librarys were not found. Try installing e2fsprogs-dev" 

##### Try to compile them all together and show the versions.
cat >conftest.c <<EOF
#include <e2p/e2p.h>
main(){ const char *v, *d; ext2fs_get_library_version(&v,&d);
printf("\nThe version of the e2fs library is: %s, %s\n", v, d);return 0;}
EOF

if gcc $LDIRS $CF $CFLAGS conftest.c $LIBS -o conftest &>conftest.log ; then
  ./conftest || err "Unable to execute a freshly compiled application, maybe you have to adjust your LD_LIBRARY_PATH or /etc/ld.so.conf"
  rm -f conftest.c conftest conftest.log
else
  err "Unable to compile a minimal application look at 'conftest.log' for errors"
 echo gcc $LIBS $LDIRS $CF $CFLAGS conftest.c -o conftest >>conftest.log
fi


echo
echo "LDFLAGS   :${LIBS}${LDIRS}"
echo "PREFIX    :${prefix:=/usr/local}"
echo "CPPFLAGS  :${CF}"
echo "CFLAGS    :${CFLAGS:=-Wall}"
echo "VERSION   :${version}"
echo

cat >Local.mak <<EOF
CPPFLAGS=$CF
CFLAGS=${CFLAGS}

LDFLAGS=$LDIRS
LIBS=$LIBS

CC=${CC:=gcc}
LD=${LD:=ld}
STRIP=${STRIP:=strip}

prefix=${prefix}
basedir=${basedir}
mandir=${mandir:=man}
VERSION=${version}

EOF

for dirs in /bin /usr/bin /usr/local/bin /sw/bin; do
  for make in gmake make; do
    if ${dirs}/${make} -v 2>/dev/null | grep GNU; then
      mak=${dirs}/${make}
    fi
  done  
done

echo
if test ! -z "${mak}"; then
  echo A usable "make" executable was found in ${mak}
else
  echo No usable "make" executable found.
fi
echo

if test "x${err_occ}" = "xY"; then
  echo
  echo An error occured. Please edit 'Local.mak' manually if compiling fails.
fi