diff --git a/m4/ax_check_openssl.m4 b/m4/ax_check_openssl.m4
new file mode 100644
index 0000000..a87c5a6
--- /dev/null
+++ b/m4/ax_check_openssl.m4
@@ -0,0 +1,124 @@
+# ===========================================================================
+#     http://www.gnu.org/software/autoconf-archive/ax_check_openssl.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_OPENSSL([action-if-found[, action-if-not-found]])
+#
+# DESCRIPTION
+#
+#   Look for OpenSSL in a number of default spots, or in a user-selected
+#   spot (via --with-openssl).  Sets
+#
+#     OPENSSL_INCLUDES to the include directives required
+#     OPENSSL_LIBS to the -l directives required
+#     OPENSSL_LDFLAGS to the -L or -R flags required
+#
+#   and calls ACTION-IF-FOUND or ACTION-IF-NOT-FOUND appropriately
+#
+#   This macro sets OPENSSL_INCLUDES such that source files should use the
+#   openssl/ directory in include directives:
+#
+#     #include <openssl/hmac.h>
+#
+# LICENSE
+#
+#   Copyright (c) 2009,2010 Zmanda Inc. <http://www.zmanda.com/>
+#   Copyright (c) 2009,2010 Dustin J. Mitchell <dustin@zmanda.com>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 8
+
+AU_ALIAS([CHECK_SSL], [AX_CHECK_OPENSSL])
+AC_DEFUN([AX_CHECK_OPENSSL], [
+    found=false
+    AC_ARG_WITH([openssl],
+        [AS_HELP_STRING([--with-openssl=DIR],
+            [root of the OpenSSL directory])],
+        [
+            case "$withval" in
+            "" | y | ye | yes | n | no)
+            AC_MSG_ERROR([Invalid --with-openssl value])
+              ;;
+            *) ssldirs="$withval"
+              ;;
+            esac
+        ], [
+            # if pkg-config is installed and openssl has installed a .pc file,
+            # then use that information and don't search ssldirs
+            AC_PATH_PROG([PKG_CONFIG], [pkg-config])
+            if test x"$PKG_CONFIG" != x""; then
+                OPENSSL_LDFLAGS=`$PKG_CONFIG openssl --libs-only-L 2>/dev/null`
+                if test $? = 0; then
+                    OPENSSL_LIBS=`$PKG_CONFIG openssl --libs-only-l 2>/dev/null`
+                    OPENSSL_INCLUDES=`$PKG_CONFIG openssl --cflags-only-I 2>/dev/null`
+                    found=true
+                fi
+            fi
+
+            # no such luck; use some default ssldirs
+            if ! $found; then
+                ssldirs="/usr/local/ssl /usr/lib/ssl /usr/ssl /usr/pkg /usr/local /usr"
+            fi
+        ]
+        )
+
+
+    # note that we #include <openssl/foo.h>, so the OpenSSL headers have to be in
+    # an 'openssl' subdirectory
+
+    if ! $found; then
+        OPENSSL_INCLUDES=
+        for ssldir in $ssldirs; do
+            AC_MSG_CHECKING([for openssl/ssl.h in $ssldir])
+            if test -f "$ssldir/include/openssl/ssl.h"; then
+                OPENSSL_INCLUDES="-I$ssldir/include"
+                OPENSSL_LDFLAGS="-L$ssldir/lib"
+                OPENSSL_LIBS="-lssl -lcrypto"
+                found=true
+                AC_MSG_RESULT([yes])
+                break
+            else
+                AC_MSG_RESULT([no])
+            fi
+        done
+
+        # if the file wasn't found, well, go ahead and try the link anyway -- maybe
+        # it will just work!
+    fi
+
+    # try the preprocessor and linker with our new flags,
+    # being careful not to pollute the global LIBS, LDFLAGS, and CPPFLAGS
+
+    AC_MSG_CHECKING([whether compiling and linking against OpenSSL works])
+    echo "Trying link with OPENSSL_LDFLAGS=$OPENSSL_LDFLAGS;" \
+        "OPENSSL_LIBS=$OPENSSL_LIBS; OPENSSL_INCLUDES=$OPENSSL_INCLUDES" >&AS_MESSAGE_LOG_FD
+
+    save_LIBS="$LIBS"
+    save_LDFLAGS="$LDFLAGS"
+    save_CPPFLAGS="$CPPFLAGS"
+    LDFLAGS="$LDFLAGS $OPENSSL_LDFLAGS"
+    LIBS="$OPENSSL_LIBS $LIBS"
+    CPPFLAGS="$OPENSSL_INCLUDES $CPPFLAGS"
+    AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM([#include <openssl/ssl.h>], [SSL_new(NULL)])],
+        [
+            AC_MSG_RESULT([yes])
+            $1
+        ], [
+            AC_MSG_RESULT([no])
+            $2
+        ])
+    CPPFLAGS="$save_CPPFLAGS"
+    LDFLAGS="$save_LDFLAGS"
+    LIBS="$save_LIBS"
+
+    AC_SUBST([OPENSSL_INCLUDES])
+    AC_SUBST([OPENSSL_LIBS])
+    AC_SUBST([OPENSSL_LDFLAGS])
+])
diff --git a/m4/ax_cxx_compile_stdcxx_11.m4 b/m4/ax_cxx_compile_stdcxx_11.m4
new file mode 100644
index 0000000..af37acd
--- /dev/null
+++ b/m4/ax_cxx_compile_stdcxx_11.m4
@@ -0,0 +1,133 @@
+# ============================================================================
+#  http://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx_11.html
+# ============================================================================
+#
+# SYNOPSIS
+#
+#   AX_CXX_COMPILE_STDCXX_11([ext|noext],[mandatory|optional])
+#
+# DESCRIPTION
+#
+#   Check for baseline language coverage in the compiler for the C++11
+#   standard; if necessary, add switches to CXXFLAGS to enable support.
+#
+#   The first argument, if specified, indicates whether you insist on an
+#   extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g.
+#   -std=c++11).  If neither is specified, you get whatever works, with
+#   preference for an extended mode.
+#
+#   The second argument, if specified 'mandatory' or if left unspecified,
+#   indicates that baseline C++11 support is required and that the macro
+#   should error out if no mode with that support is found.  If specified
+#   'optional', then configuration proceeds regardless, after defining
+#   HAVE_CXX11 if and only if a supporting mode is found.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Benjamin Kosnik <bkoz@redhat.com>
+#   Copyright (c) 2012 Zack Weinberg <zackw@panix.com>
+#   Copyright (c) 2013 Roy Stogner <roystgnr@ices.utexas.edu>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 3
+
+m4_define([_AX_CXX_COMPILE_STDCXX_11_testbody], [
+  template <typename T>
+    struct check
+    {
+      static_assert(sizeof(int) <= sizeof(T), "not big enough");
+    };
+
+    typedef check<check<bool>> right_angle_brackets;
+
+    int a;
+    decltype(a) b;
+
+    typedef check<int> check_type;
+    check_type c;
+    check_type&& cr = static_cast<check_type&&>(c);
+
+    auto d = a;
+])
+
+AC_DEFUN([AX_CXX_COMPILE_STDCXX_11], [dnl
+  m4_if([$1], [], [],
+        [$1], [ext], [],
+        [$1], [noext], [],
+        [m4_fatal([invalid argument `$1' to AX_CXX_COMPILE_STDCXX_11])])dnl
+  m4_if([$2], [], [ax_cxx_compile_cxx11_required=true],
+        [$2], [mandatory], [ax_cxx_compile_cxx11_required=true],
+        [$2], [optional], [ax_cxx_compile_cxx11_required=false],
+        [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX_11])])dnl
+  AC_LANG_PUSH([C++])dnl
+  ac_success=no
+  AC_CACHE_CHECK(whether $CXX supports C++11 features by default,
+  ax_cv_cxx_compile_cxx11,
+  [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
+    [ax_cv_cxx_compile_cxx11=yes],
+    [ax_cv_cxx_compile_cxx11=no])])
+  if test x$ax_cv_cxx_compile_cxx11 = xyes; then
+    ac_success=yes
+  fi
+
+  m4_if([$1], [noext], [], [dnl
+  if test x$ac_success = xno; then
+    for switch in -std=gnu++11 -std=gnu++0x; do
+      cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx11_$switch])
+      AC_CACHE_CHECK(whether $CXX supports C++11 features with $switch,
+                     $cachevar,
+        [ac_save_CXXFLAGS="$CXXFLAGS"
+         CXXFLAGS="$CXXFLAGS $switch"
+         AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
+          [eval $cachevar=yes],
+          [eval $cachevar=no])
+         CXXFLAGS="$ac_save_CXXFLAGS"])
+      if eval test x\$$cachevar = xyes; then
+        CXXFLAGS="$CXXFLAGS $switch"
+        ac_success=yes
+        break
+      fi
+    done
+  fi])
+
+  m4_if([$1], [ext], [], [dnl
+  if test x$ac_success = xno; then
+    for switch in -std=c++11 -std=c++0x; do
+      cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx11_$switch])
+      AC_CACHE_CHECK(whether $CXX supports C++11 features with $switch,
+                     $cachevar,
+        [ac_save_CXXFLAGS="$CXXFLAGS"
+         CXXFLAGS="$CXXFLAGS $switch"
+         AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
+          [eval $cachevar=yes],
+          [eval $cachevar=no])
+         CXXFLAGS="$ac_save_CXXFLAGS"])
+      if eval test x\$$cachevar = xyes; then
+        CXXFLAGS="$CXXFLAGS $switch"
+        ac_success=yes
+        break
+      fi
+    done
+  fi])
+  AC_LANG_POP([C++])
+  if test x$ax_cxx_compile_cxx11_required = xtrue; then
+    if test x$ac_success = xno; then
+      AC_MSG_ERROR([*** A compiler with support for C++11 language features is required.])
+    fi
+  else
+    if test x$ac_success = xno; then
+      HAVE_CXX11=0
+      AC_MSG_NOTICE([No compiler with C++11 support was found])
+    else
+      HAVE_CXX11=1
+      AC_DEFINE(HAVE_CXX11,1,
+                [define if the compiler supports basic C++11 syntax])
+    fi
+
+    AC_SUBST(HAVE_CXX11)
+  fi
+])
diff --git a/m4/ax_lib_sqlite3.m4 b/m4/ax_lib_sqlite3.m4
new file mode 100644
index 0000000..7771716
--- /dev/null
+++ b/m4/ax_lib_sqlite3.m4
@@ -0,0 +1,156 @@
+# ===========================================================================
+#      http://www.gnu.org/software/autoconf-archive/ax_lib_sqlite3.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_LIB_SQLITE3([MINIMUM-VERSION])
+#
+# DESCRIPTION
+#
+#   Test for the SQLite 3 library of a particular version (or newer)
+#
+#   This macro takes only one optional argument, required version of SQLite
+#   3 library. If required version is not passed, 3.0.0 is used in the test
+#   of existance of SQLite 3.
+#
+#   If no intallation prefix to the installed SQLite library is given the
+#   macro searches under /usr, /usr/local, and /opt.
+#
+#   This macro calls:
+#
+#     AC_SUBST(SQLITE3_CFLAGS)
+#     AC_SUBST(SQLITE3_LDFLAGS)
+#     AC_SUBST(SQLITE3_VERSION)
+#
+#   And sets:
+#
+#     HAVE_SQLITE3
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Mateusz Loskot <mateusz@loskot.net>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 14
+
+AC_DEFUN([AX_LIB_SQLITE3],
+[
+    AC_ARG_WITH([sqlite3],
+        AS_HELP_STRING(
+            [--with-sqlite3=@<:@ARG@:>@],
+            [use SQLite 3 library @<:@default=yes@:>@, optionally specify the prefix for sqlite3 library]
+        ),
+        [
+        if test "$withval" = "no"; then
+            WANT_SQLITE3="no"
+        elif test "$withval" = "yes"; then
+            WANT_SQLITE3="yes"
+            ac_sqlite3_path=""
+        else
+            WANT_SQLITE3="yes"
+            ac_sqlite3_path="$withval"
+        fi
+        ],
+        [WANT_SQLITE3="yes"]
+    )
+
+    SQLITE3_CFLAGS=""
+    SQLITE3_LDFLAGS=""
+    SQLITE3_VERSION=""
+
+    if test "x$WANT_SQLITE3" = "xyes"; then
+
+        ac_sqlite3_header="sqlite3.h"
+
+        sqlite3_version_req=ifelse([$1], [], [3.0.0], [$1])
+        sqlite3_version_req_shorten=`expr $sqlite3_version_req : '\([[0-9]]*\.[[0-9]]*\)'`
+        sqlite3_version_req_major=`expr $sqlite3_version_req : '\([[0-9]]*\)'`
+        sqlite3_version_req_minor=`expr $sqlite3_version_req : '[[0-9]]*\.\([[0-9]]*\)'`
+        sqlite3_version_req_micro=`expr $sqlite3_version_req : '[[0-9]]*\.[[0-9]]*\.\([[0-9]]*\)'`
+        if test "x$sqlite3_version_req_micro" = "x" ; then
+            sqlite3_version_req_micro="0"
+        fi
+
+        sqlite3_version_req_number=`expr $sqlite3_version_req_major \* 1000000 \
+                                   \+ $sqlite3_version_req_minor \* 1000 \
+                                   \+ $sqlite3_version_req_micro`
+
+        AC_MSG_CHECKING([for SQLite3 library >= $sqlite3_version_req])
+
+        if test "$ac_sqlite3_path" != ""; then
+            ac_sqlite3_ldflags="-L$ac_sqlite3_path/lib"
+            ac_sqlite3_cppflags="-I$ac_sqlite3_path/include"
+        else
+            for ac_sqlite3_path_tmp in /usr /usr/local /opt ; do
+                if test -f "$ac_sqlite3_path_tmp/include/$ac_sqlite3_header" \
+                    && test -r "$ac_sqlite3_path_tmp/include/$ac_sqlite3_header"; then
+                    ac_sqlite3_path=$ac_sqlite3_path_tmp
+                    ac_sqlite3_cppflags="-I$ac_sqlite3_path_tmp/include"
+                    ac_sqlite3_ldflags="-L$ac_sqlite3_path_tmp/lib"
+                    break;
+                fi
+            done
+        fi
+
+        ac_sqlite3_ldflags="$ac_sqlite3_ldflags -lsqlite3"
+
+        saved_CPPFLAGS="$CPPFLAGS"
+        CPPFLAGS="$CPPFLAGS $ac_sqlite3_cppflags"
+
+        AC_LANG_PUSH(C)
+        AC_COMPILE_IFELSE(
+            [
+            AC_LANG_PROGRAM([[@%:@include <sqlite3.h>]],
+                [[
+#if (SQLITE_VERSION_NUMBER >= $sqlite3_version_req_number)
+/* Everything is okay */
+#else
+#  error SQLite version is too old
+#endif
+                ]]
+            )
+            ],
+            [
+            AC_MSG_RESULT([yes])
+            success="yes"
+            ],
+            [
+            AC_MSG_RESULT([not found])
+            success="no"
+            ]
+        )
+        AC_LANG_POP(C)
+
+        CPPFLAGS="$saved_CPPFLAGS"
+
+        if test "$success" = "yes"; then
+
+            SQLITE3_CFLAGS="$ac_sqlite3_cppflags"
+            SQLITE3_LDFLAGS="$ac_sqlite3_ldflags"
+
+            ac_sqlite3_header_path="$ac_sqlite3_path/include/$ac_sqlite3_header"
+
+            dnl Retrieve SQLite release version
+            if test "x$ac_sqlite3_header_path" != "x"; then
+                ac_sqlite3_version=`cat $ac_sqlite3_header_path \
+                    | grep '#define.*SQLITE_VERSION.*\"' | sed -e 's/.* "//' \
+                        | sed -e 's/"//'`
+                if test $ac_sqlite3_version != ""; then
+                    SQLITE3_VERSION=$ac_sqlite3_version
+                else
+                    AC_MSG_WARN([Cannot find SQLITE_VERSION macro in sqlite3.h header to retrieve SQLite version!])
+                fi
+            fi
+
+            AC_SUBST(SQLITE3_CFLAGS)
+            AC_SUBST(SQLITE3_LDFLAGS)
+            AC_SUBST(SQLITE3_VERSION)
+            AC_DEFINE([HAVE_SQLITE3], [], [Have the SQLITE3 library])
+        fi
+    fi
+])
diff --git a/m4/ax_prefix_config_h.m4 b/m4/ax_prefix_config_h.m4
new file mode 100644
index 0000000..43a3906
--- /dev/null
+++ b/m4/ax_prefix_config_h.m4
@@ -0,0 +1,209 @@
+# ===========================================================================
+#    http://www.gnu.org/software/autoconf-archive/ax_prefix_config_h.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_PREFIX_CONFIG_H [(OUTPUT-HEADER [,PREFIX [,ORIG-HEADER]])]
+#
+# DESCRIPTION
+#
+#   This is a new variant from ac_prefix_config_ this one will use a
+#   lowercase-prefix if the config-define was starting with a
+#   lowercase-char, e.g. "#define const", "#define restrict", or "#define
+#   off_t", (and this one can live in another directory, e.g.
+#   testpkg/config.h therefore I decided to move the output-header to be the
+#   first arg)
+#
+#   takes the usual config.h generated header file; looks for each of the
+#   generated "#define SOMEDEF" lines, and prefixes the defined name (ie.
+#   makes it "#define PREFIX_SOMEDEF". The result is written to the output
+#   config.header file. The PREFIX is converted to uppercase for the
+#   conversions.
+#
+#   Defaults:
+#
+#     OUTPUT-HEADER = $PACKAGE-config.h
+#     PREFIX = $PACKAGE
+#     ORIG-HEADER, from AM_CONFIG_HEADER(config.h)
+#
+#   Your configure.ac script should contain both macros in this order, and
+#   unlike the earlier variations of this prefix-macro it is okay to place
+#   the AX_PREFIX_CONFIG_H call before the AC_OUTPUT invokation.
+#
+#   Example:
+#
+#     AC_INIT(config.h.in)        # config.h.in as created by "autoheader"
+#     AM_INIT_AUTOMAKE(testpkg, 0.1.1)    # makes #undef VERSION and PACKAGE
+#     AM_CONFIG_HEADER(config.h)          # prep config.h from config.h.in
+#     AX_PREFIX_CONFIG_H(mylib/_config.h) # prep mylib/_config.h from it..
+#     AC_MEMORY_H                         # makes "#undef NEED_MEMORY_H"
+#     AC_C_CONST_H                        # makes "#undef const"
+#     AC_OUTPUT(Makefile)                 # creates the "config.h" now
+#                                         # and also mylib/_config.h
+#
+#   if the argument to AX_PREFIX_CONFIG_H would have been omitted then the
+#   default outputfile would have been called simply "testpkg-config.h", but
+#   even under the name "mylib/_config.h" it contains prefix-defines like
+#
+#     #ifndef TESTPKG_VERSION
+#     #define TESTPKG_VERSION "0.1.1"
+#     #endif
+#     #ifndef TESTPKG_NEED_MEMORY_H
+#     #define TESTPKG_NEED_MEMORY_H 1
+#     #endif
+#     #ifndef _testpkg_const
+#     #define _testpkg_const _const
+#     #endif
+#
+#   and this "mylib/_config.h" can be installed along with other
+#   header-files, which is most convenient when creating a shared library
+#   (that has some headers) where some functionality is dependent on the
+#   OS-features detected at compile-time. No need to invent some
+#   "mylib-confdefs.h.in" manually. :-)
+#
+#   Note that some AC_DEFINEs that end up in the config.h file are actually
+#   self-referential - e.g. AC_C_INLINE, AC_C_CONST, and the AC_TYPE_OFF_T
+#   say that they "will define inline|const|off_t if the system does not do
+#   it by itself". You might want to clean up about these - consider an
+#   extra mylib/conf.h that reads something like:
+#
+#     #include <mylib/_config.h>
+#     #ifndef _testpkg_const
+#     #define _testpkg_const const
+#     #endif
+#
+#   and then start using _testpkg_const in the header files. That is also a
+#   good thing to differentiate whether some library-user has starting to
+#   take up with a different compiler, so perhaps it could read something
+#   like this:
+#
+#     #ifdef _MSC_VER
+#     #include <mylib/_msvc.h>
+#     #else
+#     #include <mylib/_config.h>
+#     #endif
+#     #ifndef _testpkg_const
+#     #define _testpkg_const const
+#     #endif
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+#   Copyright (c) 2008 Marten Svantesson
+#   Copyright (c) 2008 Gerald Point <Gerald.Point@labri.fr>
+#
+#   This program is free software; you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation; either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <http://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 11
+
+AC_DEFUN([AX_PREFIX_CONFIG_H],[dnl
+AC_PREREQ([2.62])
+AC_BEFORE([AC_CONFIG_HEADERS],[$0])dnl
+AC_CONFIG_COMMANDS([ifelse($1,,$PACKAGE-config.h,$1)],[dnl
+AS_VAR_PUSHDEF([_OUT],[ac_prefix_conf_OUT])dnl
+AS_VAR_PUSHDEF([_DEF],[ac_prefix_conf_DEF])dnl
+AS_VAR_PUSHDEF([_PKG],[ac_prefix_conf_PKG])dnl
+AS_VAR_PUSHDEF([_LOW],[ac_prefix_conf_LOW])dnl
+AS_VAR_PUSHDEF([_UPP],[ac_prefix_conf_UPP])dnl
+AS_VAR_PUSHDEF([_INP],[ac_prefix_conf_INP])dnl
+m4_pushdef([_script],[conftest.prefix])dnl
+m4_pushdef([_symbol],[m4_cr_Letters[]m4_cr_digits[]_])dnl
+_OUT=`echo ifelse($1, , $PACKAGE-config.h, $1)`
+_DEF=`echo _$_OUT | sed -e "y:m4_cr_letters:m4_cr_LETTERS[]:" -e "s/@<:@^m4_cr_Letters@:>@/_/g"`
+_PKG=`echo ifelse($2, , $PACKAGE, $2)`
+_LOW=`echo _$_PKG | sed -e "y:m4_cr_LETTERS-:m4_cr_letters[]_:"`
+_UPP=`echo $_PKG | sed -e "y:m4_cr_letters-:m4_cr_LETTERS[]_:"  -e "/^@<:@m4_cr_digits@:>@/s/^/_/"`
+_INP=`echo "ifelse($3,,,$3)" | sed -e 's/ *//'`
+if test ".$_INP" = "."; then
+   for ac_file in : $CONFIG_HEADERS; do test "_$ac_file" = _: && continue
+     case "$ac_file" in
+        *.h) _INP=$ac_file ;;
+        *)
+     esac
+     test ".$_INP" != "." && break
+   done
+fi
+if test ".$_INP" = "."; then
+   case "$_OUT" in
+      */*) _INP=`basename "$_OUT"`
+      ;;
+      *-*) _INP=`echo "$_OUT" | sed -e "s/@<:@_symbol@:>@*-//"`
+      ;;
+      *) _INP=config.h
+      ;;
+   esac
+fi
+if test -z "$_PKG" ; then
+   AC_MSG_ERROR([no prefix for _PREFIX_PKG_CONFIG_H])
+else
+  if test ! -f "$_INP" ; then if test -f "$srcdir/$_INP" ; then
+     _INP="$srcdir/$_INP"
+  fi fi
+  AC_MSG_NOTICE(creating $_OUT - prefix $_UPP for $_INP defines)
+  if test -f $_INP ; then
+    AS_ECHO(["s/^@%:@undef  *\\(@<:@m4_cr_LETTERS[]_@:>@\\)/@%:@undef $_UPP""_\\1/"]) > _script
+    AS_ECHO(["s/^@%:@undef  *\\(@<:@m4_cr_letters@:>@\\)/@%:@undef $_LOW""_\\1/"]) >> _script
+    AS_ECHO(["s/^@%:@def[]ine  *\\(@<:@m4_cr_LETTERS[]_@:>@@<:@_symbol@:>@*\\)\\(.*\\)/@%:@ifndef $_UPP""_\\1\\"]) >> _script
+    AS_ECHO(["@%:@def[]ine $_UPP""_\\1\\2\\"]) >> _script
+    AS_ECHO(["@%:@endif/"]) >> _script
+    AS_ECHO(["s/^@%:@def[]ine  *\\(@<:@m4_cr_letters@:>@@<:@_symbol@:>@*\\)\\(.*\\)/@%:@ifndef $_LOW""_\\1\\"]) >> _script
+    AS_ECHO(["@%:@define $_LOW""_\\1\\2\\"]) >> _script
+    AS_ECHO(["@%:@endif/"]) >> _script
+    # now executing _script on _DEF input to create _OUT output file
+    echo "@%:@ifndef $_DEF"      >$tmp/pconfig.h
+    echo "@%:@def[]ine $_DEF 1" >>$tmp/pconfig.h
+    echo ' ' >>$tmp/pconfig.h
+    echo /'*' $_OUT. Generated automatically at end of configure. '*'/ >>$tmp/pconfig.h
+
+    sed -f _script $_INP >>$tmp/pconfig.h
+    echo ' ' >>$tmp/pconfig.h
+    echo '/* once:' $_DEF '*/' >>$tmp/pconfig.h
+    echo "@%:@endif" >>$tmp/pconfig.h
+    if cmp -s $_OUT $tmp/pconfig.h 2>/dev/null; then
+      AC_MSG_NOTICE([$_OUT is unchanged])
+    else
+      ac_dir=`AS_DIRNAME(["$_OUT"])`
+      AS_MKDIR_P(["$ac_dir"])
+      rm -f "$_OUT"
+      mv $tmp/pconfig.h "$_OUT"
+    fi
+    cp _script _configs.sed
+  else
+    AC_MSG_ERROR([input file $_INP does not exist - skip generating $_OUT])
+  fi
+  rm -f conftest.*
+fi
+m4_popdef([_symbol])dnl
+m4_popdef([_script])dnl
+AS_VAR_POPDEF([_INP])dnl
+AS_VAR_POPDEF([_UPP])dnl
+AS_VAR_POPDEF([_LOW])dnl
+AS_VAR_POPDEF([_PKG])dnl
+AS_VAR_POPDEF([_DEF])dnl
+AS_VAR_POPDEF([_OUT])dnl
+],[PACKAGE="$PACKAGE"])])
diff --git a/m4/ax_prog_doxygen.m4 b/m4/ax_prog_doxygen.m4
new file mode 100644
index 0000000..44b22b0
--- /dev/null
+++ b/m4/ax_prog_doxygen.m4
@@ -0,0 +1,532 @@
+# ===========================================================================
+#      http://www.gnu.org/software/autoconf-archive/ax_prog_doxygen.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   DX_INIT_DOXYGEN(PROJECT-NAME, DOXYFILE-PATH, [OUTPUT-DIR])
+#   DX_DOXYGEN_FEATURE(ON|OFF)
+#   DX_DOT_FEATURE(ON|OFF)
+#   DX_HTML_FEATURE(ON|OFF)
+#   DX_CHM_FEATURE(ON|OFF)
+#   DX_CHI_FEATURE(ON|OFF)
+#   DX_MAN_FEATURE(ON|OFF)
+#   DX_RTF_FEATURE(ON|OFF)
+#   DX_XML_FEATURE(ON|OFF)
+#   DX_PDF_FEATURE(ON|OFF)
+#   DX_PS_FEATURE(ON|OFF)
+#
+# DESCRIPTION
+#
+#   The DX_*_FEATURE macros control the default setting for the given
+#   Doxygen feature. Supported features are 'DOXYGEN' itself, 'DOT' for
+#   generating graphics, 'HTML' for plain HTML, 'CHM' for compressed HTML
+#   help (for MS users), 'CHI' for generating a seperate .chi file by the
+#   .chm file, and 'MAN', 'RTF', 'XML', 'PDF' and 'PS' for the appropriate
+#   output formats. The environment variable DOXYGEN_PAPER_SIZE may be
+#   specified to override the default 'a4wide' paper size.
+#
+#   By default, HTML, PDF and PS documentation is generated as this seems to
+#   be the most popular and portable combination. MAN pages created by
+#   Doxygen are usually problematic, though by picking an appropriate subset
+#   and doing some massaging they might be better than nothing. CHM and RTF
+#   are specific for MS (note that you can't generate both HTML and CHM at
+#   the same time). The XML is rather useless unless you apply specialized
+#   post-processing to it.
+#
+#   The macros mainly control the default state of the feature. The use can
+#   override the default by specifying --enable or --disable. The macros
+#   ensure that contradictory flags are not given (e.g.,
+#   --enable-doxygen-html and --enable-doxygen-chm,
+#   --enable-doxygen-anything with --disable-doxygen, etc.) Finally, each
+#   feature will be automatically disabled (with a warning) if the required
+#   programs are missing.
+#
+#   Once all the feature defaults have been specified, call DX_INIT_DOXYGEN
+#   with the following parameters: a one-word name for the project for use
+#   as a filename base etc., an optional configuration file name (the
+#   default is 'Doxyfile', the same as Doxygen's default), and an optional
+#   output directory name (the default is 'doxygen-doc').
+#
+#   Automake Support
+#
+#   The following is a template aminclude.am file for use with Automake.
+#   Make targets and variables values are controlled by the various
+#   DX_COND_* conditionals set by autoconf.
+#
+#   The provided targets are:
+#
+#     doxygen-doc: Generate all doxygen documentation.
+#
+#     doxygen-run: Run doxygen, which will generate some of the
+#                  documentation (HTML, CHM, CHI, MAN, RTF, XML)
+#                  but will not do the post processing required
+#                  for the rest of it (PS, PDF, and some MAN).
+#
+#     doxygen-man: Rename some doxygen generated man pages.
+#
+#     doxygen-ps:  Generate doxygen PostScript documentation.
+#
+#     doxygen-pdf: Generate doxygen PDF documentation.
+#
+#   Note that by default these are not integrated into the automake targets.
+#   If doxygen is used to generate man pages, you can achieve this
+#   integration by setting man3_MANS to the list of man pages generated and
+#   then adding the dependency:
+#
+#     $(man3_MANS): doxygen-doc
+#
+#   This will cause make to run doxygen and generate all the documentation.
+#
+#   The following variable is intended for use in Makefile.am:
+#
+#     DX_CLEANFILES = everything to clean.
+#
+#   Then add this variable to MOSTLYCLEANFILES.
+#
+#     ----- begin aminclude.am -------------------------------------
+#
+#     ## --------------------------------- ##
+#     ## Format-independent Doxygen rules. ##
+#     ## --------------------------------- ##
+#
+#     if DX_COND_doc
+#
+#     ## ------------------------------- ##
+#     ## Rules specific for HTML output. ##
+#     ## ------------------------------- ##
+#
+#     if DX_COND_html
+#
+#     DX_CLEAN_HTML = @DX_DOCDIR@/html
+#
+#     endif DX_COND_html
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for CHM output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_chm
+#
+#     DX_CLEAN_CHM = @DX_DOCDIR@/chm
+#
+#     if DX_COND_chi
+#
+#     DX_CLEAN_CHI = @DX_DOCDIR@/@PACKAGE@.chi
+#
+#     endif DX_COND_chi
+#
+#     endif DX_COND_chm
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for MAN output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_man
+#
+#     DX_CLEAN_MAN = @DX_DOCDIR@/man
+#
+#     endif DX_COND_man
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for RTF output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_rtf
+#
+#     DX_CLEAN_RTF = @DX_DOCDIR@/rtf
+#
+#     endif DX_COND_rtf
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for XML output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_xml
+#
+#     DX_CLEAN_XML = @DX_DOCDIR@/xml
+#
+#     endif DX_COND_xml
+#
+#     ## ----------------------------- ##
+#     ## Rules specific for PS output. ##
+#     ## ----------------------------- ##
+#
+#     if DX_COND_ps
+#
+#     DX_CLEAN_PS = @DX_DOCDIR@/@PACKAGE@.ps
+#
+#     DX_PS_GOAL = doxygen-ps
+#
+#     doxygen-ps: @DX_DOCDIR@/@PACKAGE@.ps
+#
+#     @DX_DOCDIR@/@PACKAGE@.ps: @DX_DOCDIR@/@PACKAGE@.tag
+#         cd @DX_DOCDIR@/latex; \
+#         rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+#         $(DX_LATEX) refman.tex; \
+#         $(MAKEINDEX_PATH) refman.idx; \
+#         $(DX_LATEX) refman.tex; \
+#         countdown=5; \
+#         while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+#                           refman.log > /dev/null 2>&1 \
+#            && test $$countdown -gt 0; do \
+#             $(DX_LATEX) refman.tex; \
+#             countdown=`expr $$countdown - 1`; \
+#         done; \
+#         $(DX_DVIPS) -o ../@PACKAGE@.ps refman.dvi
+#
+#     endif DX_COND_ps
+#
+#     ## ------------------------------ ##
+#     ## Rules specific for PDF output. ##
+#     ## ------------------------------ ##
+#
+#     if DX_COND_pdf
+#
+#     DX_CLEAN_PDF = @DX_DOCDIR@/@PACKAGE@.pdf
+#
+#     DX_PDF_GOAL = doxygen-pdf
+#
+#     doxygen-pdf: @DX_DOCDIR@/@PACKAGE@.pdf
+#
+#     @DX_DOCDIR@/@PACKAGE@.pdf: @DX_DOCDIR@/@PACKAGE@.tag
+#         cd @DX_DOCDIR@/latex; \
+#         rm -f *.aux *.toc *.idx *.ind *.ilg *.log *.out; \
+#         $(DX_PDFLATEX) refman.tex; \
+#         $(DX_MAKEINDEX) refman.idx; \
+#         $(DX_PDFLATEX) refman.tex; \
+#         countdown=5; \
+#         while $(DX_EGREP) 'Rerun (LaTeX|to get cross-references right)' \
+#                           refman.log > /dev/null 2>&1 \
+#            && test $$countdown -gt 0; do \
+#             $(DX_PDFLATEX) refman.tex; \
+#             countdown=`expr $$countdown - 1`; \
+#         done; \
+#         mv refman.pdf ../@PACKAGE@.pdf
+#
+#     endif DX_COND_pdf
+#
+#     ## ------------------------------------------------- ##
+#     ## Rules specific for LaTeX (shared for PS and PDF). ##
+#     ## ------------------------------------------------- ##
+#
+#     if DX_COND_latex
+#
+#     DX_CLEAN_LATEX = @DX_DOCDIR@/latex
+#
+#     endif DX_COND_latex
+#
+#     .PHONY: doxygen-run doxygen-doc $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+#     .INTERMEDIATE: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+#     doxygen-run: @DX_DOCDIR@/@PACKAGE@.tag
+#
+#     doxygen-doc: doxygen-run $(DX_PS_GOAL) $(DX_PDF_GOAL)
+#
+#     @DX_DOCDIR@/@PACKAGE@.tag: $(DX_CONFIG) $(pkginclude_HEADERS)
+#         rm -rf @DX_DOCDIR@
+#         $(DX_ENV) $(DX_DOXYGEN) $(srcdir)/$(DX_CONFIG)
+#
+#     DX_CLEANFILES = \
+#         @DX_DOCDIR@/@PACKAGE@.tag \
+#         -r \
+#         $(DX_CLEAN_HTML) \
+#         $(DX_CLEAN_CHM) \
+#         $(DX_CLEAN_CHI) \
+#         $(DX_CLEAN_MAN) \
+#         $(DX_CLEAN_RTF) \
+#         $(DX_CLEAN_XML) \
+#         $(DX_CLEAN_PS) \
+#         $(DX_CLEAN_PDF) \
+#         $(DX_CLEAN_LATEX)
+#
+#     endif DX_COND_doc
+#
+#     ----- end aminclude.am ---------------------------------------
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Oren Ben-Kiki <oren@ben-kiki.org>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 12
+
+## ----------##
+## Defaults. ##
+## ----------##
+
+DX_ENV=""
+AC_DEFUN([DX_FEATURE_doc],  ON)
+AC_DEFUN([DX_FEATURE_dot],  OFF)
+AC_DEFUN([DX_FEATURE_man],  OFF)
+AC_DEFUN([DX_FEATURE_html], ON)
+AC_DEFUN([DX_FEATURE_chm],  OFF)
+AC_DEFUN([DX_FEATURE_chi],  OFF)
+AC_DEFUN([DX_FEATURE_rtf],  OFF)
+AC_DEFUN([DX_FEATURE_xml],  OFF)
+AC_DEFUN([DX_FEATURE_pdf],  ON)
+AC_DEFUN([DX_FEATURE_ps],   ON)
+
+## --------------- ##
+## Private macros. ##
+## --------------- ##
+
+# DX_ENV_APPEND(VARIABLE, VALUE)
+# ------------------------------
+# Append VARIABLE="VALUE" to DX_ENV for invoking doxygen.
+AC_DEFUN([DX_ENV_APPEND], [AC_SUBST([DX_ENV], ["$DX_ENV $1='$2'"])])
+
+# DX_DIRNAME_EXPR
+# ---------------
+# Expand into a shell expression prints the directory part of a path.
+AC_DEFUN([DX_DIRNAME_EXPR],
+         [[expr ".$1" : '\(\.\)[^/]*$' \| "x$1" : 'x\(.*\)/[^/]*$']])
+
+# DX_IF_FEATURE(FEATURE, IF-ON, IF-OFF)
+# -------------------------------------
+# Expands according to the M4 (static) status of the feature.
+AC_DEFUN([DX_IF_FEATURE], [ifelse(DX_FEATURE_$1, ON, [$2], [$3])])
+
+# DX_REQUIRE_PROG(VARIABLE, PROGRAM)
+# ----------------------------------
+# Require the specified program to be found for the DX_CURRENT_FEATURE to work.
+AC_DEFUN([DX_REQUIRE_PROG], [
+AC_PATH_TOOL([$1], [$2])
+if test "$DX_FLAG_[]DX_CURRENT_FEATURE$$1" = 1; then
+    AC_MSG_WARN([$2 not found - will not DX_CURRENT_DESCRIPTION])
+    AC_SUBST(DX_FLAG_[]DX_CURRENT_FEATURE, 0)
+fi
+])
+
+# DX_TEST_FEATURE(FEATURE)
+# ------------------------
+# Expand to a shell expression testing whether the feature is active.
+AC_DEFUN([DX_TEST_FEATURE], [test "$DX_FLAG_$1" = 1])
+
+# DX_CHECK_DEPEND(REQUIRED_FEATURE, REQUIRED_STATE)
+# -------------------------------------------------
+# Verify that a required features has the right state before trying to turn on
+# the DX_CURRENT_FEATURE.
+AC_DEFUN([DX_CHECK_DEPEND], [
+test "$DX_FLAG_$1" = "$2" \
+|| AC_MSG_ERROR([doxygen-DX_CURRENT_FEATURE ifelse([$2], 1,
+                            requires, contradicts) doxygen-DX_CURRENT_FEATURE])
+])
+
+# DX_CLEAR_DEPEND(FEATURE, REQUIRED_FEATURE, REQUIRED_STATE)
+# ----------------------------------------------------------
+# Turn off the DX_CURRENT_FEATURE if the required feature is off.
+AC_DEFUN([DX_CLEAR_DEPEND], [
+test "$DX_FLAG_$1" = "$2" || AC_SUBST(DX_FLAG_[]DX_CURRENT_FEATURE, 0)
+])
+
+# DX_FEATURE_ARG(FEATURE, DESCRIPTION,
+#                CHECK_DEPEND, CLEAR_DEPEND,
+#                REQUIRE, DO-IF-ON, DO-IF-OFF)
+# --------------------------------------------
+# Parse the command-line option controlling a feature. CHECK_DEPEND is called
+# if the user explicitly turns the feature on (and invokes DX_CHECK_DEPEND),
+# otherwise CLEAR_DEPEND is called to turn off the default state if a required
+# feature is disabled (using DX_CLEAR_DEPEND). REQUIRE performs additional
+# requirement tests (DX_REQUIRE_PROG). Finally, an automake flag is set and
+# DO-IF-ON or DO-IF-OFF are called according to the final state of the feature.
+AC_DEFUN([DX_ARG_ABLE], [
+    AC_DEFUN([DX_CURRENT_FEATURE], [$1])
+    AC_DEFUN([DX_CURRENT_DESCRIPTION], [$2])
+    AC_ARG_ENABLE(doxygen-$1,
+                  [AS_HELP_STRING(DX_IF_FEATURE([$1], [--disable-doxygen-$1],
+                                                      [--enable-doxygen-$1]),
+                                  DX_IF_FEATURE([$1], [don't $2], [$2]))],
+                  [
+case "$enableval" in
+#(
+y|Y|yes|Yes|YES)
+    AC_SUBST([DX_FLAG_$1], 1)
+    $3
+;; #(
+n|N|no|No|NO)
+    AC_SUBST([DX_FLAG_$1], 0)
+;; #(
+*)
+    AC_MSG_ERROR([invalid value '$enableval' given to doxygen-$1])
+;;
+esac
+], [
+AC_SUBST([DX_FLAG_$1], [DX_IF_FEATURE([$1], 1, 0)])
+$4
+])
+if DX_TEST_FEATURE([$1]); then
+    $5
+    :
+fi
+AM_CONDITIONAL(DX_COND_$1, DX_TEST_FEATURE([$1]))
+if DX_TEST_FEATURE([$1]); then
+    $6
+    :
+else
+    $7
+    :
+fi
+])
+
+## -------------- ##
+## Public macros. ##
+## -------------- ##
+
+# DX_XXX_FEATURE(DEFAULT_STATE)
+# -----------------------------
+AC_DEFUN([DX_DOXYGEN_FEATURE], [AC_DEFUN([DX_FEATURE_doc],  [$1])])
+AC_DEFUN([DX_DOT_FEATURE],     [AC_DEFUN([DX_FEATURE_dot], [$1])])
+AC_DEFUN([DX_MAN_FEATURE],     [AC_DEFUN([DX_FEATURE_man],  [$1])])
+AC_DEFUN([DX_HTML_FEATURE],    [AC_DEFUN([DX_FEATURE_html], [$1])])
+AC_DEFUN([DX_CHM_FEATURE],     [AC_DEFUN([DX_FEATURE_chm],  [$1])])
+AC_DEFUN([DX_CHI_FEATURE],     [AC_DEFUN([DX_FEATURE_chi],  [$1])])
+AC_DEFUN([DX_RTF_FEATURE],     [AC_DEFUN([DX_FEATURE_rtf],  [$1])])
+AC_DEFUN([DX_XML_FEATURE],     [AC_DEFUN([DX_FEATURE_xml],  [$1])])
+AC_DEFUN([DX_XML_FEATURE],     [AC_DEFUN([DX_FEATURE_xml],  [$1])])
+AC_DEFUN([DX_PDF_FEATURE],     [AC_DEFUN([DX_FEATURE_pdf],  [$1])])
+AC_DEFUN([DX_PS_FEATURE],      [AC_DEFUN([DX_FEATURE_ps],   [$1])])
+
+# DX_INIT_DOXYGEN(PROJECT, [CONFIG-FILE], [OUTPUT-DOC-DIR])
+# ---------------------------------------------------------
+# PROJECT also serves as the base name for the documentation files.
+# The default CONFIG-FILE is "Doxyfile" and OUTPUT-DOC-DIR is "doxygen-doc".
+AC_DEFUN([DX_INIT_DOXYGEN], [
+
+# Files:
+AC_SUBST([DX_PROJECT], [$1])
+AC_SUBST([DX_CONFIG], [ifelse([$2], [], Doxyfile, [$2])])
+AC_SUBST([DX_DOCDIR], [ifelse([$3], [], doxygen-doc, [$3])])
+
+# Environment variables used inside doxygen.cfg:
+DX_ENV_APPEND(SRCDIR, $srcdir)
+DX_ENV_APPEND(PROJECT, $DX_PROJECT)
+DX_ENV_APPEND(DOCDIR, $DX_DOCDIR)
+DX_ENV_APPEND(VERSION, $PACKAGE_VERSION)
+
+# Doxygen itself:
+DX_ARG_ABLE(doc, [generate any doxygen documentation],
+            [],
+            [],
+            [DX_REQUIRE_PROG([DX_DOXYGEN], doxygen)
+             DX_REQUIRE_PROG([DX_PERL], perl)],
+            [DX_ENV_APPEND(PERL_PATH, $DX_PERL)])
+
+# Dot for graphics:
+DX_ARG_ABLE(dot, [generate graphics for doxygen documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_DOT], dot)],
+            [DX_ENV_APPEND(HAVE_DOT, YES)
+             DX_ENV_APPEND(DOT_PATH, [`DX_DIRNAME_EXPR($DX_DOT)`])],
+            [DX_ENV_APPEND(HAVE_DOT, NO)])
+
+# Man pages generation:
+DX_ARG_ABLE(man, [generate doxygen manual pages],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_MAN, YES)],
+            [DX_ENV_APPEND(GENERATE_MAN, NO)])
+
+# RTF file generation:
+DX_ARG_ABLE(rtf, [generate doxygen RTF documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_RTF, YES)],
+            [DX_ENV_APPEND(GENERATE_RTF, NO)])
+
+# XML file generation:
+DX_ARG_ABLE(xml, [generate doxygen XML documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_XML, YES)],
+            [DX_ENV_APPEND(GENERATE_XML, NO)])
+
+# (Compressed) HTML help generation:
+DX_ARG_ABLE(chm, [generate doxygen compressed HTML help documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_HHC], hhc)],
+            [DX_ENV_APPEND(HHC_PATH, $DX_HHC)
+             DX_ENV_APPEND(GENERATE_HTML, YES)
+             DX_ENV_APPEND(GENERATE_HTMLHELP, YES)],
+            [DX_ENV_APPEND(GENERATE_HTMLHELP, NO)])
+
+# Seperate CHI file generation.
+DX_ARG_ABLE(chi, [generate doxygen seperate compressed HTML help index file],
+            [DX_CHECK_DEPEND(chm, 1)],
+            [DX_CLEAR_DEPEND(chm, 1)],
+            [],
+            [DX_ENV_APPEND(GENERATE_CHI, YES)],
+            [DX_ENV_APPEND(GENERATE_CHI, NO)])
+
+# Plain HTML pages generation:
+DX_ARG_ABLE(html, [generate doxygen plain HTML documentation],
+            [DX_CHECK_DEPEND(doc, 1) DX_CHECK_DEPEND(chm, 0)],
+            [DX_CLEAR_DEPEND(doc, 1) DX_CLEAR_DEPEND(chm, 0)],
+            [],
+            [DX_ENV_APPEND(GENERATE_HTML, YES)],
+            [DX_TEST_FEATURE(chm) || DX_ENV_APPEND(GENERATE_HTML, NO)])
+
+# PostScript file generation:
+DX_ARG_ABLE(ps, [generate doxygen PostScript documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_LATEX], latex)
+             DX_REQUIRE_PROG([DX_MAKEINDEX], makeindex)
+             DX_REQUIRE_PROG([DX_DVIPS], dvips)
+             DX_REQUIRE_PROG([DX_EGREP], egrep)])
+
+# PDF file generation:
+DX_ARG_ABLE(pdf, [generate doxygen PDF documentation],
+            [DX_CHECK_DEPEND(doc, 1)],
+            [DX_CLEAR_DEPEND(doc, 1)],
+            [DX_REQUIRE_PROG([DX_PDFLATEX], pdflatex)
+             DX_REQUIRE_PROG([DX_MAKEINDEX], makeindex)
+             DX_REQUIRE_PROG([DX_EGREP], egrep)])
+
+# LaTeX generation for PS and/or PDF:
+AM_CONDITIONAL(DX_COND_latex, DX_TEST_FEATURE(ps) || DX_TEST_FEATURE(pdf))
+if DX_TEST_FEATURE(ps) || DX_TEST_FEATURE(pdf); then
+    DX_ENV_APPEND(GENERATE_LATEX, YES)
+else
+    DX_ENV_APPEND(GENERATE_LATEX, NO)
+fi
+
+# Paper size for PS and/or PDF:
+AC_ARG_VAR(DOXYGEN_PAPER_SIZE,
+           [a4wide (default), a4, letter, legal or executive])
+case "$DOXYGEN_PAPER_SIZE" in
+#(
+"")
+    AC_SUBST(DOXYGEN_PAPER_SIZE, "")
+;; #(
+a4wide|a4|letter|legal|executive)
+    DX_ENV_APPEND(PAPER_SIZE, $DOXYGEN_PAPER_SIZE)
+;; #(
+*)
+    AC_MSG_ERROR([unknown DOXYGEN_PAPER_SIZE='$DOXYGEN_PAPER_SIZE'])
+;;
+esac
+
+#For debugging:
+#echo DX_FLAG_doc=$DX_FLAG_doc
+#echo DX_FLAG_dot=$DX_FLAG_dot
+#echo DX_FLAG_man=$DX_FLAG_man
+#echo DX_FLAG_html=$DX_FLAG_html
+#echo DX_FLAG_chm=$DX_FLAG_chm
+#echo DX_FLAG_chi=$DX_FLAG_chi
+#echo DX_FLAG_rtf=$DX_FLAG_rtf
+#echo DX_FLAG_xml=$DX_FLAG_xml
+#echo DX_FLAG_pdf=$DX_FLAG_pdf
+#echo DX_FLAG_ps=$DX_FLAG_ps
+#echo DX_ENV=$DX_ENV
+])