dnl Some useful functions for LyXs configure.in                 -*- sh -*-
dnl Author: Jean-Marc Lasgouttes (Jean-Marc.Lasgouttes@inria.fr)
dnl         Lars Gullik Bjønnes (larsbj@lyx.org)
dnl         Allan Rae (rae@lyx.org)

dnl Compute the default build type from AC_PACKAGE_VERSION at autoconf time.
m4_define([LYX_BUILD_TYPE], [m4_bmatch(AC_PACKAGE_VERSION,
    [dev], [development],
    [pre\|alpha\|beta\|rc\|RC], [prerelease],
    [release])])


dnl Usage LYX_CHECK_VERSION   Displays version of LyX being built and
dnl sets variable "build_type"
AC_DEFUN([LYX_CHECK_VERSION],[
echo "configuring LyX version" AC_PACKAGE_VERSION

AC_MSG_CHECKING([for build type])
lyx_devel_version=no
lyx_prerelease=no
AC_ARG_ENABLE(build-type,
  AS_HELP_STRING([--enable-build-type=STR],[set build type to rel(ease), pre(release), dev(elopment), prof(iling), or gprof (default: LYX_BUILD_TYPE)]),
  [case $enableval in
    dev*) build_type=development;;
    pre*) build_type=prerelease;;
    prof*)  build_type=profiling;;
    gprof*) build_type=gprof;;
    rel*) build_type=release;;
    *) AC_MSG_ERROR([bad build type specification '$enableval'. Please use one of rel(ease), pre(release), dev(elopment), prof(iling), or gprof]);;
   esac],
  [build_type=LYX_BUILD_TYPE])
AC_MSG_RESULT([$build_type])
lyx_flags="$lyx_flags build=$build_type"
case $build_type in
    development) lyx_devel_version=yes
		 LYX_DATE="not released yet" ;;
    prerelease) lyx_prerelease=yes ;;
esac

AC_SUBST(lyx_devel_version)
])


dnl Define the option to set a LyX version on installed executables and directories
dnl
dnl
AC_DEFUN([LYX_VERSION_SUFFIX],[
AC_MSG_CHECKING([for version suffix])
dnl We need the literal double quotes in the rpm spec file
RPM_VERSION_SUFFIX='""'
AC_ARG_WITH(version-suffix,
  [AS_HELP_STRING([--with-version-suffix@<:@=STR@:>@], install lyx files as lyxSTR (default STR: -AC_PACKAGE_VERSION))],
  [if test "x$withval" = "xyes";
   then
     withval="-"AC_PACKAGE_VERSION
     ac_configure_args=`echo "$ac_configure_args" | sed "s,--with-version-suffix,--with-version-suffix=$withval,"`
   fi
   AC_SUBST(version_suffix,$withval)
   RPM_VERSION_SUFFIX="--with-version-suffix=$withval"])
AC_SUBST(RPM_VERSION_SUFFIX)
AC_SUBST(program_base_name,"lyx")
AC_MSG_RESULT([$withval])
])


dnl Check whether to configure for Qt5, or Qt6. Default is Qt6.
dnl
AC_DEFUN([LYX_CHECK_QT6],[
AC_MSG_CHECKING([whether Qt6 is requested])
AC_ARG_ENABLE([qt6],
  [AS_HELP_STRING([--disable-qt6],[do not use Qt6 for building])],
  USE_QT6=$enableval, USE_QT6=yes)
AC_MSG_RESULT([$USE_QT6])
AC_SUBST([USE_QT6])
])
dnl


dnl Usage: LYX_WARNING(message)  Displays the warning "message" and sets the
dnl flag lyx_warning to yes.
AC_DEFUN([LYX_WARNING],[
lyx_warning_txt="$lyx_warning_txt
== $1
"
lyx_warning=yes])


dnl Usage: LYX_LIB_ERROR(file,library)  Displays an error message indication
dnl  that 'file' cannot be found because 'lib' may be uncorrectly installed.
AC_DEFUN([LYX_LIB_ERROR],[
AC_MSG_ERROR([cannot find $1. Please check that the $2 library
   is correctly installed on your system.])])


dnl Usage: LYX_CHECK_WARNINGS  Displays a warning message if a LYX_WARNING
dnl   has occurred previously.
AC_DEFUN([LYX_CHECK_WARNINGS],[
if test x$lyx_warning = xyes; then
cat <<EOF
=== The following minor problems have been detected by configure.
=== Please check the messages below before running 'make'.
=== (see the section 'Problems' in the INSTALL file)
$lyx_warning_txt

EOF
fi])


dnl LYX_SEARCH_PROG(VARIABLE-NAME,PROGRAMS-LIST,ACTION-IF-FOUND)
dnl
define(LYX_SEARCH_PROG,[dnl
for ac_prog in $2 ; do
# Extract the first word of "$ac_prog", so it can be a program name with args.
  set dummy $ac_prog ; ac_word=$[2]
  if test -z "[$]$1"; then
    IFS="${IFS=	}"; ac_save_ifs="$IFS"; IFS=":"
    for ac_dir in $PATH; do
      test -z "$ac_dir" && ac_dir=.
      if test -f [$ac_dir/$ac_word]; then
	$1="$ac_prog"
	break
      fi
    done
    IFS="$ac_save_ifs"
  fi

  if test -n "[$]$1"; then
    ac_result=yes
  else
    ac_result=no
  fi
  ifelse($3,,,[$3])
  test -n "[$]$1" && break
done
])dnl


dnl Usage: LYX_PROG_CLANG: set CLANG to yes if the compiler is clang.
AC_DEFUN([LYX_PROG_CLANG],
[AC_CACHE_CHECK([whether the compiler is clang],
               [lyx_cv_prog_clang],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[
#ifndef __clang__
	    this is not clang
#endif
]])],[lyx_cv_prog_clang=yes ; CLANG=yes],[lyx_cv_prog_clang=no ; CLANG=no])])
if test $CLANG = yes ; then
  AC_CACHE_CHECK([for clang version],
    [lyx_cv_clang_version],
    [clang_noversion=no
     AC_COMPUTE_INT(clang_major,__clang_major__,,[clang_noversion_=yes])
     AC_COMPUTE_INT(clang_minor,__clang_minor__,,[clang_noversion_=yes])
     AC_COMPUTE_INT(clang_patchlevel,__clang_patchlevel__,,[clang_noversion_=yes])
     if test $clang_noversion = yes ; then
       clang_version=unknown
     else
       clang_version=$clang_major.$clang_minor.$clang_patchlevel
     fi
     lyx_cv_clang_version=$clang_version])
fi
])


dnl Usage: LYX_CXX_CXX17_FLAGS(VERSION): add to AM_CXXFLAGS the best flag that
dnl selects C++17 mode; gives an error when C++17 mode is not found.
dnl VERSION is a list of years to try (e.g. 17 or {20,17}).
AC_DEFUN([LYX_CXX_CXX17_FLAGS],
[AC_CACHE_CHECK([for a good C++ mode], [lyx_cv_cxx17_flags],
 [lyx_cv_cxx17_flags=none
  for flag in `eval echo -std=c++$1 default -std=gnu++$1` ; do
    if test $flag = default ; then
      flag=
    fi
    save_CPPFLAGS=$CPPFLAGS
    CPPFLAGS="$AM_CPPFLAGS $CPPFLAGS"
    save_CXXFLAGS=$CXXFLAGS
    CXXFLAGS="$flag $AM_CXXFLAGS $CXXFLAGS"
    dnl sample openmp source code to test
    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
       template <typename T>
       struct check
       {
	   static_assert(sizeof(int) <= sizeof(T), "not big enough");
       };

       typedef check<check<bool>> right_angle_brackets;

       class TestDeleted
       {
       public:
	   TestDeleted() = delete;
       };


       int a;
       decltype(a) b;

       typedef check<int> check_type;
       check_type c;
       check_type&& cr = static_cast<check_type&&>(c);

       auto d = a;

       #include <any>
       std::any any_var = 10;]], [[]])],[lyx_cv_cxx17_flags=$flag; break],[])
   CXXFLAGS=$save_CXXFLAGS
   CPPFLAGS=$save_CPPFLAGS
  done])
  if test x$lyx_cv_cxx17_flags = xnone ; then
    AC_MSG_ERROR([Cannot find suitable mode for compiler $CXX])
  fi
  AM_CXXFLAGS="$lyx_cv_cxx17_flags $AM_CXXFLAGS"
])


dnl Usage: LYX_LIB_STDCXX: set lyx_cv_lib_stdcxx to yes if the STL library is libstdc++.
AC_DEFUN([LYX_LIB_STDCXX],
[AC_CACHE_CHECK([whether STL is libstdc++],
               [lyx_cv_lib_stdcxx],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include<vector>]], [[
#if ! defined(__GLIBCXX__) && ! defined(__GLIBCPP__)
	    this is not libstdc++
#endif
]])],[lyx_cv_lib_stdcxx=yes],[lyx_cv_lib_stdcxx=no])])
])


AC_DEFUN([LYX_PROG_CXX],
[AC_REQUIRE([AC_PROG_CXX])
AC_REQUIRE([AC_PROG_CXXCPP])

### We might want to force the C++ standard.
AC_ARG_ENABLE(cxx-mode,
  AS_HELP_STRING([--enable-cxx-mode],[choose C++ standard (default: 17)]),,
  dnl put modes in curly braces if there are several of them (ex. {20,17}
  [enable_cxx_mode=17]
)

AC_LANG_PUSH(C++)
LYX_PROG_CLANG
LYX_CXX_CXX17_FLAGS($enable_cxx_mode)
LYX_LIB_STDCXX
AC_LANG_POP(C++)

### We might want to get or shut warnings.
AC_ARG_ENABLE(warnings,
  AS_HELP_STRING([--enable-warnings],[tell the compiler to display more warnings]),,
  [ if test $lyx_devel_version = yes -o $lyx_prerelease = yes && test $GXX = yes ; then
	enable_warnings=yes;
    else
	enable_warnings=no;
    fi;])
if test x$enable_warnings = xyes ; then
  lyx_flags="$lyx_flags warnings"
fi

### We might want to disable debug
AC_ARG_ENABLE(debug,
  AS_HELP_STRING([--enable-debug],[enable debug information]),,
  [AS_CASE([$build_type], [rel*], [enable_debug=no], [enable_debug=yes])]
)

AC_ARG_ENABLE(stdlib-debug,
  AS_HELP_STRING([--enable-stdlib-debug],[enable debug mode in libstdc++]),,
  [enable_stdlib_debug=no]
)

AC_ARG_ENABLE(stdlib-assertions,
  AS_HELP_STRING([--enable-stdlib-assertions],[enable assertions in libstdc++]),,
  [AS_CASE([$build_type], [dev*], [enable_stdlib_assertions=yes],
	  [enable_stdlib_assertions=no])]
)

### set up optimization
AC_ARG_ENABLE(optimization,
    AS_HELP_STRING([--enable-optimization@<:@=ARG@:>@],[enable compiler optimisation]),,
    enable_optimization=yes;)
case $enable_optimization in
    yes)
        if test $enable_debug = yes -a $build_type != "profiling" ; then
            lyx_optim=-Og
        else
            lyx_optim=-O2
        fi;;
    no) lyx_optim=;;
    *) lyx_optim=${enable_optimization};;
esac

AC_ARG_ENABLE(assertions,
  AS_HELP_STRING([--enable-assertions],[add runtime sanity checks in the program]),,
  [AS_CASE([$build_type], [dev*|pre*], [enable_assertions=yes],
	  [enable_assertions=no])]
)
if test "x$enable_assertions" = xyes ; then
   lyx_flags="$lyx_flags assertions"
   AC_DEFINE(ENABLE_ASSERTIONS,1,
    [Define if you want assertions to be enabled in the code])
fi

# set the compiler options correctly.
if test x$GXX = xyes; then
  dnl clang++ pretends to be g++ 4.2.1; this is not useful
  if test x$CLANG = xno; then
    dnl Useful for global version info
    gxx_version=`${CXX} -dumpversion`
    case $gxx_version in
	*.*) ;;
	*) gxx_version=`${CXX} -dumpfullversion` ;;
    esac
    CXX_VERSION="($gxx_version)"
  else
    gxx_version=clang-$clang_version
    CXX_VERSION="($clang_version)"
  fi

  case $gxx_version in
      2.*|3.*|4.*) AC_MSG_ERROR([gcc >= 5 is required]);;
  esac

  AM_CXXFLAGS="$lyx_optim $AM_CXXFLAGS"
  if test x$enable_debug = xyes ; then
      AM_CXXFLAGS="-g $AM_CXXFLAGS"
  fi
  if test $build_type = gprof ; then
    AM_CXXFLAGS="$AM_CXXFLAGS -pg"
    AM_LDFLAGS="$AM_LDFLAGS -pg"
  fi
  if test $build_type = profiling ; then
    AM_CXXFLAGS="$AM_CXXFLAGS -fno-omit-frame-pointer"
  fi

  AS_CASE([$host], [*mingw*|*cygwin*], [], [AM_CXXFLAGS="-fPIC $AM_CXXFLAGS"])

  dnl Warnings are for preprocessor too
  if test x$enable_warnings = xyes ; then
      AM_CPPFLAGS="$AM_CPPFLAGS -Wall -Wextra"
  fi
  if test x$enable_stdlib_debug = xyes ; then
    dnl FIXME: for clang/libc++, one should define _LIBCPP_DEBUG2=0
    dnl See http://clang-developers.42468.n3.nabble.com/libc-debug-mode-td3336742.html
    if test x$lyx_cv_lib_stdcxx = xyes ; then
        lyx_flags="$lyx_flags stdlib-debug"
	AC_DEFINE(_GLIBCXX_DEBUG, 1, [libstdc++ debug mode])
	AC_DEFINE(_GLIBCXX_DEBUG_PEDANTIC, 1, [libstdc++ pedantic debug mode])
	AC_SUBST(STDLIB_DEBUG, "-D_GLIBCXX_DEBUG -D_GLIBCXX_DEBUG_PEDANTIC")
    else
	enable_stdlib_debug=no
    fi
  fi
  if test x$enable_stdlib_assertions = xyes ; then
    if test x$lyx_cv_lib_stdcxx = xyes ; then
        lyx_flags="$lyx_flags stdlib-assertions"
	AC_DEFINE(_GLIBCXX_ASSERTIONS, 1, [libstdc++ assertions mode])
    else
	enable_stdlib_assertions=no
    fi
  fi
fi

# Some additional flags may be needed
dnl if test x$GXX = xyes; then
dnl     case $gxx_version in
dnl       clang-3.0*|clang-3.1*|clang-3.2*|clang-3.3*)
dnl     esac
dnl fi
])

dnl Usage: LYX_USE_INCLUDED_NOD : select if the included nod should be used.
AC_DEFUN([LYX_USE_INCLUDED_NOD],[
	AC_MSG_CHECKING([whether to use included nod library])
	AC_ARG_WITH(included-nod,
	    [AS_HELP_STRING([--without-included-nod], [do not use the nod lib supplied with LyX, try to find one in the system directories - compilation will abort if nothing suitable is found])],
	    [lyx_cv_with_included_nod=$withval],
	    [lyx_cv_with_included_nod=yes])
	AM_CONDITIONAL(USE_INCLUDED_NOD, test x$lyx_cv_with_included_nod = xyes)
	AC_MSG_RESULT([$lyx_cv_with_included_nod])
	if test x$lyx_cv_with_included_nod = xyes ; then
	    lyx_included_libs="$lyx_included_libs nod"
	    NOD_INCLUDES='-I$(top_srcdir)/3rdparty/nod'
	else
	    NOD_INCLUDES=
	    AC_LANG_PUSH(C++)
	    AC_MSG_CHECKING([for nod library])
	    AC_LINK_IFELSE(
		[AC_LANG_PROGRAM([#include <nod.hpp>],
		    [nod::scoped_connection conn;])],
		[AC_MSG_RESULT([yes])],
		[AC_MSG_RESULT([no])
		AC_MSG_ERROR([cannot find suitable nod library (do not use --without-included-nod)])
	    ])
	    AC_LANG_POP(C++)
	fi
	AC_SUBST(NOD_INCLUDES)
])

dnl Usage: LYX_USE_INCLUDED_ICONV : select if the included iconv should
dnl        be used.
AC_DEFUN([LYX_USE_INCLUDED_ICONV],[
  AC_MSG_CHECKING([whether to use included iconv library])
  AC_ARG_WITH(included-iconv,
    [AS_HELP_STRING([--with-included-iconv], [use the iconv lib supplied with LyX instead of the system one])],
    [lyx_cv_with_included_iconv=$withval],
    [lyx_cv_with_included_iconv=no])
  AM_CONDITIONAL(USE_INCLUDED_ICONV, test x$lyx_cv_with_included_iconv = xyes)
  AC_MSG_RESULT([$lyx_cv_with_included_iconv])
  if test x$lyx_cv_with_included_iconv = xyes ; then
  lyx_included_libs="$lyx_included_libs iconv"

dnl This is hardcoded to make it compile
    AC_DEFINE([HAVE_WORKING_O_NOFOLLOW], 0, [Define to 1 if O_NOFOLLOW works.])

dnl Some bits from libiconv configure.ac to avoid a nested configure call:
    AC_EILSEQ
    AC_TYPE_MBSTATE_T
    AC_CHECK_FUNCS([getc_unlocked mbrtowc wcrtomb mbsinit setlocale])
dnl Ymbstate_t is used if HAVE_WCRTOMB || HAVE_MBRTOWC, see 3rdparty/libiconv/1.15/lib/loop_wchar.h.
    if test $ac_cv_func_wcrtomb = yes || test $ac_cv_func_mbrtowc = yes; then
      USE_MBSTATE_T=1
    else
      USE_MBSTATE_T=0
    fi
    AC_SUBST([USE_MBSTATE_T])
    AC_CACHE_CHECK([whether <wchar.h> is standalone],
      [gl_cv_header_wchar_h_standalone],
      [AC_COMPILE_IFELSE(
        [AC_LANG_PROGRAM(
          [[#include <wchar.h>
            wchar_t w;]],
          [[]])],
        [gl_cv_header_wchar_h_standalone=yes],
        [gl_cv_header_wchar_h_standalone=no])])
    if test $gl_cv_header_wchar_h_standalone = yes; then
      BROKEN_WCHAR_H=0
    else
      BROKEN_WCHAR_H=1
    fi
    AC_SUBST([BROKEN_WCHAR_H])
dnl we want const correctness
    AC_DEFINE_UNQUOTED([ICONV_CONST], [const],
      [Define as const if the declaration of iconv() needs const.])
    ICONV_CONST=const
    AC_SUBST([ICONV_CONST])
dnl we build a static lib
    DLL_VARIABLE=
    AC_SUBST([DLL_VARIABLE])
    ICONV_INCLUDES='-I$(top_srcdir)/3rdparty/libiconv/1.15 -I$(top_builddir)/3rdparty/libiconv'
    ICONV_LIBS='\$(top_builddir)/3rdparty/libiconv/liblyxiconv.a'
    ICONV_ICONV_H_IN=3rdparty/libiconv/iconv.h:3rdparty/libiconv/1.15/include/iconv.h.in
  else
    ICONV_INCLUDES=
    AM_ICONV
    if test "$am_cv_func_iconv" = no; then
      AC_MSG_ERROR([cannot find required library iconv.])
    else
      ICONV_LIBS="$LIBICONV"
    fi
    ICONV_ICONV_H_IN=
  fi
  AC_SUBST(ICONV_INCLUDES)
  AC_SUBST(ICONV_LIBS)
  AC_SUBST(ICONV_ICONV_H_IN)
])


dnl Usage: LYX_USE_INCLUDED_ZLIB : select if the included zlib should
dnl        be used.
AC_DEFUN([LYX_USE_INCLUDED_ZLIB],[
  AC_MSG_CHECKING([whether to use included zlib library])
  AC_ARG_WITH(included-zlib,
    [AS_HELP_STRING([--with-included-zlib], [use the zlib lib supplied with LyX instead of the system one])],
    [lyx_cv_with_included_zlib=$withval],
    [lyx_cv_with_included_zlib=no])
  AM_CONDITIONAL(USE_INCLUDED_ZLIB, test x$lyx_cv_with_included_zlib = xyes)
  AC_MSG_RESULT([$lyx_cv_with_included_zlib])
  if test x$lyx_cv_with_included_zlib = xyes ; then
    lyx_included_libs="$lyx_included_libs zlib"
    ZLIB_INCLUDES='-I$(top_srcdir)/3rdparty/zlib/1.2.8 -I$(top_builddir)/3rdparty/zlib'
    ZLIB_LIBS='$(top_builddir)/3rdparty/zlib/liblyxzlib.a'
    mkdir -p 3rdparty/zlib
dnl include standard config.h for HAVE_UNISTD_H
    echo "#include <../../config.h>" > 3rdparty/zlib/zconf.h
dnl prevent clash with system zlib that might be dragged in by other libs
    echo "#define Z_PREFIX 1" >> 3rdparty/zlib/zconf.h
    cat "${srcdir}/3rdparty/zlib/1.2.8/zconf.h.in" >> 3rdparty/zlib/zconf.h
  else
    ZLIB_INCLUDES=
    AC_CHECK_HEADERS(zlib.h,
      [AC_CHECK_LIB(z, gzopen, [ZLIB_LIBS="-lz"], LYX_LIB_ERROR(libz,zlib))],
      [LYX_LIB_ERROR(zlib.h,zlib)])
  fi
  AC_SUBST(ZLIB_INCLUDES)
  AC_SUBST(ZLIB_LIBS)
])


dnl Usage: LYX_BUILD_INCLUDED_DTL : select if the included dtl should
dnl        be built and installed.
AC_DEFUN([LYX_BUILD_INCLUDED_DTL],[
	AC_MSG_CHECKING([whether to build dv2dt and dt2dv])
	AC_ARG_WITH(included-dtl,
	    [AS_HELP_STRING([--with-included-dtl], [build and install the dv2dt and dt2dv programs supplied with LyX])],
	    [lyx_cv_with_included_dtl=$withval],
	    [lyx_cv_with_included_dtl=no])
	AM_CONDITIONAL(BUILD_INCLUDED_DTL, test x$lyx_cv_with_included_dtl = xyes)
	AC_MSG_RESULT([$lyx_cv_with_included_dtl])
	if test x$lyx_cv_with_included_dtl = xyes ; then
	    lyx_flags="$lyx_flags build-dtl"
	fi])


dnl Usage: LYX_CHECK_CALLSTACK_PRINTING: define LYX_CALLSTACK_PRINTING if the
dnl        necessary APIs are available to print callstacks.
AC_DEFUN([LYX_CHECK_CALLSTACK_PRINTING],
[AC_ARG_ENABLE([callstack-printing],
               [AS_HELP_STRING([--disable-callstack-printing],[do not print a callstack when crashing])],
               lyx_callstack_printing=$enableval, lyx_callstack_printing=yes)

if test x"$lyx_callstack_printing" = xyes; then
  AC_CACHE_CHECK([whether printing callstack is possible],
		 [lyx_cv_callstack_printing],
  [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
  #include <execinfo.h>
  #include <cxxabi.h>
  ]], [[
	  void* array[200];
	  size_t size = backtrace(array, 200);
	  backtrace_symbols(array, size);
	  int status = 0;
	  abi::__cxa_demangle("abcd", 0, 0, &status);
  ]])],[lyx_cv_callstack_printing=yes],[lyx_cv_callstack_printing=no])])
fi
if test x"$lyx_cv_callstack_printing" = xyes; then
  AC_DEFINE([LYX_CALLSTACK_PRINTING], 1,
            [Define if callstack can be printed])
  lyx_flags="$lyx_flags callback-printing"
  AM_LDFLAGS="${AM_LDFLAGS} -rdynamic"
fi
])


dnl Usage: LYX_USE_INCLUDED_MYTHES : select if the included MyThes should
dnl        be used.
AC_DEFUN([LYX_USE_INCLUDED_MYTHES],[
  AC_ARG_WITH(included-mythes,
    [AS_HELP_STRING([--with-included-mythes], [force to use the MyThes lib supplied with LyX])],
    [use_included_mythes=$withval],
    [use_included_mythes=no])
  if test x$use_included_mythes != xyes ; then
    AC_LANG_PUSH(C++)
    use_included_mythes=yes
    AC_CHECK_HEADERS([mythes.hxx mythes/mythes.hxx],
      [mythes_h_location="<$ac_header>"
       save_LIBS=$LIBS
       AC_MSG_CHECKING([checking for MyThes library])
       for ac_lib in mythes mythes-1.2 ; do
	 LIBS="-l$ac_lib $save_LIBS"
	 AC_LINK_IFELSE(
	   [AC_LANG_PROGRAM([#include <cstdio>]
              [#include $mythes_h_location], [MyThes dummy("idx","dat")])],
	   [MYTHES_LIBS=-l$ac_lib
            AC_MSG_RESULT([$MYTHES_LIBS])
	    use_included_mythes=no])
       done
       if test $use_included_mythes != no ; then
	 AC_MSG_RESULT([not found])
       fi
       break])
    AC_LANG_POP(C++)
  fi
  if test $use_included_mythes = yes ; then
    mythes_h_location="<mythes.hxx>"
    MYTHES_INCLUDES='-I$(top_srcdir)/3rdparty/mythes/1.2.5/'
    MYTHES_LIBS='$(top_builddir)/3rdparty/mythes/liblyxmythes.a'
    lyx_included_libs="$lyx_included_libs mythes"
  fi
  AM_CONDITIONAL(USE_INCLUDED_MYTHES, test x$use_included_mythes = xyes)
  AC_DEFINE_UNQUOTED(MYTHES_H_LOCATION,$mythes_h_location,[Location of mythes.hxx])
  AC_SUBST(MYTHES_INCLUDES)
  AC_SUBST(MYTHES_LIBS)
  AC_MSG_CHECKING([whether to use included MyThes library])
  AC_MSG_RESULT([$use_included_mythes])
])


dnl Usage: LYX_CHECK_MACOS_DEPLOYMENT_TARGET : select the macos deployment target
dnl                       [default-auto-value])
dnl  Assign the macosx-version-min value for compiler, linker and Info.plist.
dnl  Default is dynamic - depends on used Qt library version.
AC_DEFUN([LYX_CHECK_MACOS_DEPLOYMENT_TARGET],[
  AC_ARG_WITH(macos-deployment-target,
    [AS_HELP_STRING([--with-macos-deployment-target], [force the macos deployment target for LyX])],
    [macos_deployment_target=$withval],
    [macos_deployment_target=auto])
  if test "${macos_deployment_target}" = "auto" ; then
    macos_deployment_target="10.10"
    case "$QTLIB_VERSION" in
    5.12.*)
      macos_deployment_target="10.12"
      ;;
    6.*)
      macos_deployment_target="10.14"
      ;;
    esac
  fi
  AM_CPPFLAGS="-mmacosx-version-min=$macos_deployment_target $AM_CPPFLAGS"
  AM_LDFLAGS="-mmacosx-version-min=$macos_deployment_target $AM_LDFLAGS"
  AC_SUBST(macos_deployment_target,"${macos_deployment_target}")
  AC_MSG_CHECKING([the macos deployment target for LyX])
  AC_MSG_RESULT([$macos_deployment_target])
])


dnl Usage: LYX_WITH_DIR(dir-name,desc,dir-var-name,default-value,
dnl                       [default-yes-value])
dnl  Adds a --with-'dir-name' option (described by 'desc') and puts the
dnl  resulting directory name in 'dir-var-name'.
AC_DEFUN([LYX_WITH_DIR],[
  AC_ARG_WITH($1,[AS_HELP_STRING([--with-$1],[specify $2])])
  AC_MSG_CHECKING([for $2])
  if test -z "$with_$3"; then
     AC_CACHE_VAL(lyx_cv_$3, lyx_cv_$3=$4)
  else
    test "x$with_$3" = xyes && with_$3=$5
    lyx_cv_$3="$with_$3"
  fi
  AC_MSG_RESULT($lyx_cv_$3)
])


dnl Usage: LYX_LOOP_DIR(value,action)
dnl Executes action for values of variable `dir' in `values'. `values' can
dnl use ":" as a separator.
AC_DEFUN([LYX_LOOP_DIR],[
IFS="${IFS=	}"; ac_save_ifs="$IFS"; IFS="${IFS}:"
for dir in `eval "echo $1"`; do
  if test ! "$dir" = NONE; then
    test ! -d "$dir" && AC_MSG_ERROR(['$dir' is not a directory])
    $2
  fi
done
IFS=$ac_save_ifs
])


dnl Usage: LYX_ADD_LIB_DIR(var-name,dir) Adds a -L directive to variable
dnl var-name.
AC_DEFUN([LYX_ADD_LIB_DIR],[
$1="${$1} -L$2"
if test "`(uname) 2>/dev/null`" = SunOS &&
    uname -r | grep '^5' >/dev/null; then
  if test $GXX = yes ; then
    $1="${$1} -Wl[,]-R$2"
  else
    $1="${$1} -R$2"
  fi
fi])


dnl Usage: LYX_ADD_INC_DIR(var-name,dir) Adds a -I directive to variable
dnl var-name.
AC_DEFUN([LYX_ADD_INC_DIR],[$1="${$1} -I$2 "])

### Check for a headers existence and location iff it exists
## This is supposed to be a generalised version of LYX_STL_STRING_FWD
## It almost works.  I've tried a few variations but they give errors
## of one sort or other: bad substitution or file not found etc.  The
## actual header _is_ found though and the cache variable is set however
## the reported setting (on screen) is equal to $ac_safe for some unknown
## reason.
## Additionally, autoheader can't figure out what to use as the name in
## the config.h.in file so we need to write our own entries there -- one for
## each header in the form PATH_HEADER_NAME_H
##
AC_DEFUN([LYX_PATH_HEADER],
[ AC_CHECK_HEADER($1,[
  ac_tr_safe=PATH_`echo $ac_safe | sed 'y%abcdefghijklmnopqrstuvwxyz./-%ABCDEFGHIJKLMNOPQRSTUVWXYZ___%'`
### the only remaining problem is getting the second parameter to this
### AC_CACHE_CACHE to print correctly. Currently it just results in value
### of $ac_safe being printed.
  AC_CACHE_CHECK([path to $1],[lyx_cv_path2_$ac_safe],
  [ cat > conftest.$ac_ext <<EOF
#line __oline__ "configure"
#include "confdefs.h"

#include <$1>
EOF
lyx_path_header_path=`(eval "$ac_cpp conftest.$ac_ext") 2>&5 | \
  grep $1  2>/dev/null | \
  sed -e 's/.*\(".*$1"\).*/\1/' -e "1q"`
eval "lyx_cv_path2_${ac_safe}=\$lyx_path_header_path"
rm -f conftest*])
  AC_DEFINE_UNQUOTED($ac_tr_safe, $lyx_path_header_path, [dummy])])
])
### end of LYX_PATH_HEADER

## Check what kind of packaging should be used at install time.
## The default is autodetected.
AC_DEFUN([LYX_USE_PACKAGING],
[AC_MSG_CHECKING([what packaging should be used])
AC_ARG_WITH(packaging,
  [AS_HELP_STRING([--with-packaging=STR], [set packaging for installation among:
			    posix, windows, macosx, haiku (default is autodetected)])],
  [lyx_use_packaging="$withval"], [
  case $host in
    *-apple-darwin*) lyx_use_packaging=macosx ;;
    *-pc-mingw*) lyx_use_packaging=windows ;;
    *-mingw32*) lyx_use_packaging=windows ;;
    *haiku*) lyx_use_packaging=haiku ;;
    *) lyx_use_packaging=posix ;;
  esac])
AC_MSG_RESULT($lyx_use_packaging)
lyx_install_posix=false
lyx_install_macosx=false
lyx_install_cygwin=false
lyx_install_windows=false
case $lyx_use_packaging in
   macosx) AC_DEFINE(USE_MACOSX_PACKAGING, 1, [Define to 1 if LyX should use a MacOS X application bundle file layout])
	   PACKAGE=LyX${version_suffix}
	   default_prefix="/Applications/${PACKAGE}.app"
	   AC_SUBST(osx_bundle_program_name,"${program_base_name}")
	   bindir='${prefix}/Contents/MacOS'
	   libdir='${prefix}/Contents/Resources'
	   datarootdir='${prefix}/Contents/Resources'
	   pkgdatadir='${datadir}'
	   mandir='${datadir}/man'
	   lyx_install_macosx=true ;;
  windows) AC_DEFINE(USE_WINDOWS_PACKAGING, 1, [Define to 1 if LyX should use a Windows-style file layout])
	   PACKAGE=LyX${version_suffix}
	   default_prefix="C:/Program Files/${PACKAGE}"
	   bindir='${prefix}/bin'
	   libdir='${prefix}/Resources'
	   datarootdir='${prefix}/Resources'
	   pkgdatadir='${datadir}'
	   mandir='${prefix}/Resources/man'
	   lyx_install_windows=true ;;
    posix) AC_DEFINE(USE_POSIX_PACKAGING, 1, [Define to 1 if LyX should use a POSIX-style file layout])
	   PACKAGE=lyx${version_suffix}
	   program_suffix=$version_suffix
	   pkgdatadir='${datadir}/${PACKAGE}'
	   default_prefix=$ac_default_prefix
	   case ${host} in
	     *cygwin*) lyx_install_cygwin=true ;;
	     *apple-darwin*) lyx_install_macosx=true ;;
	   esac
	   lyx_install_posix=true ;;
	haiku) AC_DEFINE(USE_HAIKU_PACKAGING, 1, [Define to 1 if LyX should use a Haiku-style file layout])
	   PACKAGE=lyx${version_suffix}
	   program_suffix=$version_suffix
	   pkgdatadir='${datadir}/${PACKAGE}'
	   default_prefix=$ac_default_prefix
	   lyx_install_posix=true ;;
    *) AC_MSG_ERROR([unknown packaging type $lyx_use_packaging.]) ;;
esac
AM_CONDITIONAL(INSTALL_MACOSX, $lyx_install_macosx)
AM_CONDITIONAL(INSTALL_WINDOWS, $lyx_install_windows)
AM_CONDITIONAL(INSTALL_CYGWIN, $lyx_install_cygwin)
AM_CONDITIONAL(INSTALL_POSIX, $lyx_install_posix)
AC_SUBST(pkgdatadir)
AC_SUBST(program_suffix)
])


## ------------------------------------------------------------------------
## Check whether mkdir() is mkdir or _mkdir, and whether it takes
## one or two arguments.
##
## http://ac-archive.sourceforge.net/C_Support/ac_func_mkdir.html
## ------------------------------------------------------------------------
##
AC_DEFUN([AC_FUNC_MKDIR],
[AC_CHECK_FUNCS([mkdir _mkdir])
AC_CACHE_CHECK([whether mkdir takes one argument],
               [ac_cv_mkdir_takes_one_arg],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
#include <sys/stat.h>
#if HAVE_UNISTD_H
#  include <unistd.h>
#endif
]], [[mkdir (".");]])],[ac_cv_mkdir_takes_one_arg=yes],[ac_cv_mkdir_takes_one_arg=no])])
if test x"$ac_cv_mkdir_takes_one_arg" = xyes; then
  AC_DEFINE([MKDIR_TAKES_ONE_ARG], 1,
            [Define if mkdir takes only one argument.])
fi
])


dnl Set VAR to the canonically resolved absolute equivalent of PATHNAME,
dnl (which may be a relative path, and need not refer to any existing
dnl entity).

dnl On Win32-MSYS build hosts, the returned path is resolved to its true
dnl native Win32 path name, (but with slashes, not backslashes).

dnl On any other system, it is simply the result which would be obtained
dnl if PATHNAME represented an existing directory, and the pwd command was
dnl executed in that directory.
AC_DEFUN([MSYS_AC_CANONICAL_PATH],
[ac_dir="$2"
 ( exec 2>/dev/null; cd / && pwd -W ) | grep ':' >/dev/null &&
    ac_pwd_w="pwd -W" || ac_pwd_w=pwd
 until ac_val=`exec 2>/dev/null; cd "$ac_dir" && $ac_pwd_w`
 do
   ac_dir=`AS_DIRNAME(["$ac_dir"])`
 done
 ac_dir=`echo "$ac_dir" | sed 's?^[[./]]*??'`
 ac_val=`echo "$ac_val" | sed 's?/*$[]??'`
 $1=`echo "$2" | sed "s?^[[./]]*$ac_dir/*?$ac_val/?"'
   s?/*$[]??'`
])

dnl this is used by the macro blow to general a proper config.h.in entry
m4_define([LYX_AH_CHECK_DECL],
[AH_TEMPLATE(AS_TR_CPP(HAVE_DECL_$1),
  [Define if you have the prototype for function `$1'])])dnl`

dnl Check things are declared in headers to avoid errors or warnings.
dnl Called like LYX_CHECK_DECL(function, header1 header2...)
dnl Defines HAVE_DECL_{FUNCTION}
AC_DEFUN([LYX_CHECK_DECL],
[LYX_AH_CHECK_DECL($1)
for ac_header in $2
do
  AC_MSG_CHECKING([if $1 is declared by header $ac_header])
  AC_EGREP_HEADER($1, $ac_header,
      [AC_MSG_RESULT(yes)
       AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_DECL_$1))
       break],
      [AC_MSG_RESULT(no)])
done])

dnl this is used by the macro below to generate a proper config.h.in entry
m4_define([LYX_AH_CHECK_DEF],
[AH_TEMPLATE(AS_TR_CPP(HAVE_DEF_$1),
  [Define to 1 if `$1' is defined in `$2'])])dnl'

dnl Check whether name is defined in header by using it in codesnippet.
dnl Called like LYX_CHECK_DEF(name, header, codesnippet)
dnl Defines HAVE_DEF_{NAME}
AC_DEFUN([LYX_CHECK_DEF],
[LYX_AH_CHECK_DEF($1, $2)
 AC_MSG_CHECKING([whether $1 is defined by header $2])
 save_CPPFLAGS=$CPPFLAGS
 CPPFLAGS="$AM_CPPFLAGS $CPPFLAGS"
 save_CXXFLAGS=$CXXFLAGS
 CXXFLAGS="$AM_CXXFLAGS $CXXFLAGS"
 AC_LANG_PUSH(C++)
 AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <$2>]], [[$3]])],[lyx_have_def_name=yes],[lyx_have_def_name=no])
 AC_LANG_POP(C++)
 CXXFLAGS=$save_CXXFLAGS
 CPPFLAGS=$save_CPPFLAGS
 AC_MSG_RESULT($lyx_have_def_name)
 if test "x$lyx_have_def_name" = xyes; then
   AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_DEF_$1))
 fi
])

dnl Extract the single digits from PACKAGE_VERSION and make them available.
dnl Defines LYX_MAJOR_VERSION, LYX_MINOR_VERSION, LYX_RELEASE_LEVEL,
dnl LYX_RELEASE_PATCH (possibly equal to 0), LYX_DIR_VER, and LYX_USERDIR_VER.
AC_DEFUN([LYX_SET_VERSION_INFO],
[lyx_major=`echo $PACKAGE_VERSION | sed -e 's/[[.]].*//'`
 lyx_patch=`echo $PACKAGE_VERSION | sed -e "s/^$lyx_major//" -e 's/^.//'`
 lyx_minor=`echo $lyx_patch | sed -e 's/[[.]].*//'`
 lyx_patch=`echo $lyx_patch | sed -e "s/^$lyx_minor//" -e 's/^.//'`
 lyx_release=`echo $lyx_patch | sed -e 's/[[^0-9]].*//'`
 lyx_patch=`echo $lyx_patch | sed -e "s/^$lyx_release//" -e 's/^[[.]]//' -e 's/[[^0-9]].*//'`
 test "x$lyx_patch" = "x" && lyx_patch=0
 lyx_dir_ver=LYX_DIR_${lyx_major}${lyx_minor}x
 lyx_userdir_ver=LYX_USERDIR_${lyx_major}${lyx_minor}x
 AC_SUBST(LYX_MAJOR_VERSION,$lyx_major)
 AC_SUBST(LYX_MINOR_VERSION,$lyx_minor)
 AC_SUBST(LYX_RELEASE_LEVEL,$lyx_release)
 AC_SUBST(LYX_RELEASE_PATCH,$lyx_patch)
 AC_SUBST(LYX_DIR_VER,"$lyx_dir_ver")
 AC_SUBST(LYX_USERDIR_VER,"$lyx_userdir_ver")
])

AC_DEFUN([LYX_CHECK_WITH_SAXON],
[
	lyx_use_saxon=true
	AC_ARG_WITH(saxon, AS_HELP_STRING([--without-saxon],[do not install saxon library (epub export)]))
	test "$with_saxon" = "no" && lyx_use_saxon=false

	if $lyx_use_saxon ; then
		AC_MSG_RESULT(Set to installing internal saxon.)
	fi

	AM_CONDITIONAL(SAXON_INSTALL, $lyx_use_saxon)
    ])

AC_DEFUN([LYX_CHECK_WITH_XSLT_SHEETS],
[
	lyx_use_xslt_stylesheets=true
	AC_ARG_WITH(xslt-stylesheets, AS_HELP_STRING([--without-xslt-stylesheets],[do not install XSLT Stylesheets (epub export)]))
	test "$with_xslt_stylesheets" = "no" && lyx_use_xslt_stylesheets=false

	if $lyx_use_xslt_stylesheets ; then
		AC_MSG_RESULT(Set to installing XSLT Stylesheets.)
	fi

	AM_CONDITIONAL(XSLT_SHEETS_INSTALL, $lyx_use_xslt_stylesheets)
    ])