dnl
dnl Autoconf support for finding Berkeley DB
dnl

AC_DEFUN([AC_DB_HELP], [
AC_MSG_NOTICE([
Could not find Berkeley DB.  Stasis includes benchmarks that use it.
They will not be built.

If your installed version is not one of the ones searched for, you may
have to specify it with --with-dbver.

If your installation is in a non-standard path, you can specify
it with --with-db=DIR.
])])

dnl
dnl Main macro for finding a usable db installation 
dnl
AC_DEFUN([AC_CONFIG_DB], [
    ac_dbvers='4.4 4.3 4.2'
    ac_dbdir='yes'

    AC_ARG_WITH(db,
        AC_HELP_STRING([--with-db=DIR],
    		   [location of a Berkeley DB installation (default system)]),
        ac_dbdir=$withval) 

    AC_ARG_WITH(dbver,
        AC_HELP_STRING([--with-dbver=VERSION],
    		   Berkeley DB versions to try (default 4.3 or 4.2)),
        ac_dbvers=$withval)

    dnl
    dnl First make sure we even want it
    dnl
    if test x$ac_dbdir = xno ; then
    DB_ENABLED=0
    else
    DB_ENABLED=1

    dnl
    dnl Now check if we have a cached value, and if not, find it.
    dnl
    if test ! x$dtn_cv_path_db_h = x ; then
        echo "checking for Berkeley DB installation... (cached) $dtn_cv_path_db_h/db.h, $dtn_cv_path_db_lib -l$dtn_cv_lib_db"
#        echo "checking for Berkeley DB installation... (cached) $dtn_cv_path_db_h/db_cxx.h, 
#$dtn_cv_path_db_lib -l$dtn_cv_lib_db"
    else
        AC_FIND_DB
    fi

    if test ! $dtn_cv_path_db_h = /usr/include ; then
        CPPFLAGS="$CPPFLAGS -I$dtn_cv_path_db_h"
    fi

    if test ! $dtn_cv_path_db_lib = /usr/lib ; then
        LDFLAGS="$LDFLAGS -L$dtn_cv_path_db_lib"
    fi

    #LIBS="$LIBS -l$dtn_cv_lib_db"
    DB_LIBS="-l$dtn_cv_lib_db"

    fi # DB_ENABLED

    AC_SUBST(DB_ENABLED)
    AC_SUBST(DB_LIBS)
    AM_CONDITIONAL(DB_ENABLED, test x$ac_dbdir != xno)
    #AM_CONDITIONAL(DB_ENABLED, $DB_ENABLED)
])

dnl
dnl Find db
dnl
AC_DEFUN([AC_FIND_DB], [
    dtn_cv_path_db_h=
    dtn_cv_path_db_lib=
    dtn_cv_lib_db=

    ac_save_CPPFLAGS="$CPPFLAGS"
    ac_save_LDFLAGS="$LDFLAGS"
    ac_save_LIBS="$LIBS"

    AC_LANG_PUSH(C++)

    for ac_dbver in $ac_dbvers ; do

    ac_dbver_major=`echo $ac_dbver | cut -d . -f1`
    ac_dbver_minor=`echo $ac_dbver | cut -d . -f2`

    if test ! x"$ac_dbdir" = x"yes" ; then
        ac_dbincdirs=$ac_dbdir/include
    else
        ac_dbincdirs="/usr/include /usr/local/include/db4 /usr/local/include/db42"
        ac_dbincdirs="$ac_dbincdirs /usr/include/db$ac_dbver"
        ac_dbincdirs="$ac_dbincdirs /usr/local/BerkeleyDB.$ac_dbver/include"
    fi

    if test ! x"$ac_dbdir" = x"yes" ; then
        ac_dblibdirs="$ac_dbdir/lib"
    else
        ac_dblibdirs="/usr/lib /usr/local/lib /usr/local/lib/db42"
        ac_dblibdirs="$ac_dblibdirs /usr/local/BerkeleyDB.$ac_dbver/lib"
    fi

    for ac_dbincdir in $ac_dbincdirs; do
	CPPFLAGS="$ac_save_CPPFLAGS -I$ac_dbincdir"
	LDFLAGS="$ac_save_LDFLAGS"
	LIBS="$ac_save_LIBS"

	dnl
	dnl First check the version in the header file. If there's a match, 
	dnl fall through to the other check to make sure it links.
	dnl If not, then we can break out of the two inner loops.
	dnl
        AC_MSG_CHECKING([for Berkeley DB header (version $ac_dbver) in $ac_dbincdir])
	AC_LINK_IFELSE(
	  AC_LANG_PROGRAM(
	    [
                #include <db.h>
           
                #if (DB_VERSION_MAJOR != ${ac_dbver_major}) || \
                    (DB_VERSION_MINOR != ${ac_dbver_minor})
                #error "incorrect version"
                #endif
            ],
            
            [
            ]),
          [ 
	      AC_MSG_RESULT([yes])
          ],
          [
              AC_MSG_RESULT([no])
	      continue
          ])

      for ac_dblibdir in $ac_dblibdirs; do
      for ac_dblib    in db-$ac_dbver; do

	LDFLAGS="$ac_save_LDFLAGS -L$ac_dblibdir"
	LIBS="$ac_save_LIBS -l$ac_dblib"

        AC_MSG_CHECKING([for Berkeley DB library in $ac_dblibdir, -l$ac_dblib])
	AC_LINK_IFELSE(
	  AC_LANG_PROGRAM(
	    [
                #include <db.h>
            ],
            
            [
	        DB *db;
                db_create(&db, NULL, 0);
            ]),

          [
              AC_MSG_RESULT([yes])
              dtn_cv_path_db_h=$ac_dbincdir
              dtn_cv_path_db_lib=$ac_dblibdir
              dtn_cv_lib_db=$ac_dblib
              break 4
          ],
          [
              AC_MSG_RESULT([no])
          ])
    done
    done
    done
    done

    AC_LANG_POP(C++)

    CPPFLAGS="$ac_save_CPPFLAGS"
    LDFLAGS="$ac_save_LDFLAGS"
    LIBS="$ac_save_LIBS"

    if test x$dtn_cv_path_db_h = x ; then
        AC_DB_HELP
        #AC_MSG_WARN([can't find usable Berkeley DB installation])
	DB_ENABLED=0
    fi
])