Adding upstream version 0.11.2.upstream/0.11.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

23 files changed, 3791 insertions, 0 deletions

diff --git a/m4/ax_ac_append_to_file.m4 b/m4/ax_ac_append_to_file.m4
new file mode 100644
index 0000000..242b3d5
--- /dev/null
+++ b/m4/ax_ac_append_to_file.m4
@@ -0,0 +1,32 @@
+# ===========================================================================
+#   https://www.gnu.org/software/autoconf-archive/ax_ac_append_to_file.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_AC_APPEND_TO_FILE([FILE],[DATA])
+#
+# DESCRIPTION
+#
+#   Appends the specified data to the specified Autoconf is run. If you want
+#   to append to a file when configure is run use AX_APPEND_TO_FILE instead.
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Allan Caffee <allan.caffee@gmail.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 10
+
+AC_DEFUN([AX_AC_APPEND_TO_FILE],[
+AC_REQUIRE([AX_FILE_ESCAPES])
+m4_esyscmd(
+AX_FILE_ESCAPES
+[
+printf "%s" "$2" >> "$1"
+])
+])
diff --git a/m4/ax_ac_print_to_file.m4 b/m4/ax_ac_print_to_file.m4
new file mode 100644
index 0000000..642dfc1
--- /dev/null
+++ b/m4/ax_ac_print_to_file.m4
@@ -0,0 +1,32 @@
+# ===========================================================================
+#   https://www.gnu.org/software/autoconf-archive/ax_ac_print_to_file.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_AC_PRINT_TO_FILE([FILE],[DATA])
+#
+# DESCRIPTION
+#
+#   Writes the specified data to the specified file when Autoconf is run. If
+#   you want to print to a file when configure is run use AX_PRINT_TO_FILE
+#   instead.
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Allan Caffee <allan.caffee@gmail.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 10
+
+AC_DEFUN([AX_AC_PRINT_TO_FILE],[
+m4_esyscmd(
+AC_REQUIRE([AX_FILE_ESCAPES])
+[
+printf "%s" "$2" > "$1"
+])
+])
diff --git a/m4/ax_add_am_macro_static.m4 b/m4/ax_add_am_macro_static.m4
new file mode 100644
index 0000000..6442d24
--- /dev/null
+++ b/m4/ax_add_am_macro_static.m4
@@ -0,0 +1,28 @@
+# ===========================================================================
+#  https://www.gnu.org/software/autoconf-archive/ax_add_am_macro_static.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_ADD_AM_MACRO_STATIC([RULE])
+#
+# DESCRIPTION
+#
+#   Adds the specified rule to $AMINCLUDE.
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Tom Howard <tomhoward@users.sf.net>
+#   Copyright (c) 2009 Allan Caffee <allan.caffee@gmail.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
+
+AC_DEFUN([AX_ADD_AM_MACRO_STATIC],[
+  AC_REQUIRE([AX_AM_MACROS_STATIC])
+  AX_AC_APPEND_TO_FILE(AMINCLUDE_STATIC,[$1])
+])
diff --git a/m4/ax_am_macros_static.m4 b/m4/ax_am_macros_static.m4
new file mode 100644
index 0000000..f4cee8c
--- /dev/null
+++ b/m4/ax_am_macros_static.m4
@@ -0,0 +1,38 @@
+# ===========================================================================
+#   https://www.gnu.org/software/autoconf-archive/ax_am_macros_static.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_AM_MACROS_STATIC
+#
+# DESCRIPTION
+#
+#   Adds support for macros that create Automake rules. You must manually
+#   add the following line
+#
+#     include $(top_srcdir)/aminclude_static.am
+#
+#   to your Makefile.am files.
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Tom Howard <tomhoward@users.sf.net>
+#   Copyright (c) 2009 Allan Caffee <allan.caffee@gmail.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 11
+
+AC_DEFUN([AMINCLUDE_STATIC],[aminclude_static.am])
+
+AC_DEFUN([AX_AM_MACROS_STATIC],
+[
+AX_AC_PRINT_TO_FILE(AMINCLUDE_STATIC,[
+# ]AMINCLUDE_STATIC[ generated automatically by Autoconf
+# from AX_AM_MACROS_STATIC on ]m4_esyscmd([LC_ALL=C date])[
+])
+])
diff --git a/m4/ax_check_gnu_make.m4 b/m4/ax_check_gnu_make.m4
new file mode 100644
index 0000000..785dc96
--- /dev/null
+++ b/m4/ax_check_gnu_make.m4
@@ -0,0 +1,95 @@
+# ===========================================================================
+#    https://www.gnu.org/software/autoconf-archive/ax_check_gnu_make.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_GNU_MAKE([run-if-true],[run-if-false])
+#
+# DESCRIPTION
+#
+#   This macro searches for a GNU version of make. If a match is found:
+#
+#     * The makefile variable `ifGNUmake' is set to the empty string, otherwise
+#       it is set to "#". This is useful for including a special features in a
+#       Makefile, which cannot be handled by other versions of make.
+#     * The makefile variable `ifnGNUmake' is set to #, otherwise
+#       it is set to the empty string. This is useful for including a special
+#       features in a Makefile, which can be handled
+#       by other versions of make or to specify else like clause.
+#     * The variable `_cv_gnu_make_command` is set to the command to invoke
+#       GNU make if it exists, the empty string otherwise.
+#     * The variable `ax_cv_gnu_make_command` is set to the command to invoke
+#       GNU make by copying `_cv_gnu_make_command`, otherwise it is unset.
+#     * If GNU Make is found, its version is extracted from the output of
+#       `make --version` as the last field of a record of space-separated
+#       columns and saved into the variable `ax_check_gnu_make_version`.
+#     * Additionally if GNU Make is found, run shell code run-if-true
+#       else run shell code run-if-false.
+#
+#   Here is an example of its use:
+#
+#   Makefile.in might contain:
+#
+#     # A failsafe way of putting a dependency rule into a makefile
+#     $(DEPEND):
+#             $(CC) -MM $(srcdir)/*.c > $(DEPEND)
+#
+#     @ifGNUmake@ ifeq ($(DEPEND),$(wildcard $(DEPEND)))
+#     @ifGNUmake@ include $(DEPEND)
+#     @ifGNUmake@ else
+#     fallback code
+#     @ifGNUmake@ endif
+#
+#   Then configure.in would normally contain:
+#
+#     AX_CHECK_GNU_MAKE()
+#     AC_OUTPUT(Makefile)
+#
+#   Then perhaps to cause gnu make to override any other make, we could do
+#   something like this (note that GNU make always looks for GNUmakefile
+#   first):
+#
+#     if  ! test x$_cv_gnu_make_command = x ; then
+#             mv Makefile GNUmakefile
+#             echo .DEFAULT: > Makefile ;
+#             echo \  $_cv_gnu_make_command \$@ >> Makefile;
+#     fi
+#
+#   Then, if any (well almost any) other make is called, and GNU make also
+#   exists, then the other make wraps the GNU make.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 John Darrington <j.darrington@elvis.murdoch.edu.au>
+#   Copyright (c) 2015 Enrico M. Crisostomo <enrico.m.crisostomo@gmail.com>
+#
+#   Copying and distribution of this file, with or without modification, are
+#   permitted in any medium without royalty provided the copyright notice
+#   and this notice are preserved. This file is offered as-is, without any
+#   warranty.
+
+#serial 12
+
+AC_DEFUN([AX_CHECK_GNU_MAKE],dnl
+  [AC_PROG_AWK
+  AC_CACHE_CHECK([for GNU make],[_cv_gnu_make_command],[dnl
+    _cv_gnu_make_command="" ;
+dnl Search all the common names for GNU make
+    for a in "$MAKE" make gmake gnumake ; do
+      if test -z "$a" ; then continue ; fi ;
+      if "$a" --version 2> /dev/null | grep GNU 2>&1 > /dev/null ; then
+        _cv_gnu_make_command=$a ;
+        AX_CHECK_GNU_MAKE_HEADLINE=$("$a" --version 2> /dev/null | grep "GNU Make")
+        ax_check_gnu_make_version=$(echo ${AX_CHECK_GNU_MAKE_HEADLINE} | ${AWK} -F " " '{ print $(NF); }')
+        break ;
+      fi
+    done ;])
+dnl If there was a GNU version, then set @ifGNUmake@ to the empty string, '#' otherwise
+  AS_VAR_IF([_cv_gnu_make_command], [""], [AS_VAR_SET([ifGNUmake], ["#"])],   [AS_VAR_SET([ifGNUmake], [""])])
+  AS_VAR_IF([_cv_gnu_make_command], [""], [AS_VAR_SET([ifnGNUmake], [""])],   [AS_VAR_SET([ifnGNUmake], ["#"])])
+  AS_VAR_IF([_cv_gnu_make_command], [""], [AS_UNSET(ax_cv_gnu_make_command)], [AS_VAR_SET([ax_cv_gnu_make_command], [${_cv_gnu_make_command}])])
+  AS_VAR_IF([_cv_gnu_make_command], [""],[$2],[$1])
+  AC_SUBST([ifGNUmake])
+  AC_SUBST([ifnGNUmake])
+])
diff --git a/m4/ax_check_link_flag.m4 b/m4/ax_check_link_flag.m4
new file mode 100644
index 0000000..819409a
--- /dev/null
+++ b/m4/ax_check_link_flag.m4
@@ -0,0 +1,74 @@
+# ===========================================================================
+#    https://www.gnu.org/software/autoconf-archive/ax_check_link_flag.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
+#
+# DESCRIPTION
+#
+#   Check whether the given FLAG works with the linker or gives an error.
+#   (Warnings, however, are ignored)
+#
+#   ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
+#   success/failure.
+#
+#   If EXTRA-FLAGS is defined, it is added to the linker's default flags
+#   when the check is done.  The check is thus made with the flags: "LDFLAGS
+#   EXTRA-FLAGS FLAG".  This can for example be used to force the linker to
+#   issue an error when a bad flag is given.
+#
+#   INPUT gives an alternative input source to AC_LINK_IFELSE.
+#
+#   NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
+#   macro in sync with AX_CHECK_{PREPROC,COMPILE}_FLAG.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+#   Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
+#
+#   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 <https://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 5
+
+AC_DEFUN([AX_CHECK_LINK_FLAG],
+[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
+AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl
+AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [
+  ax_check_save_flags=$LDFLAGS
+  LDFLAGS="$LDFLAGS $4 $1"
+  AC_LINK_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
+    [AS_VAR_SET(CACHEVAR,[yes])],
+    [AS_VAR_SET(CACHEVAR,[no])])
+  LDFLAGS=$ax_check_save_flags])
+AS_VAR_IF(CACHEVAR,yes,
+  [m4_default([$2], :)],
+  [m4_default([$3], :)])
+AS_VAR_POPDEF([CACHEVAR])dnl
+])dnl AX_CHECK_LINK_FLAGS
diff --git a/m4/ax_check_pcre2.m4 b/m4/ax_check_pcre2.m4
new file mode 100644
index 0000000..857a8c8
--- /dev/null
+++ b/m4/ax_check_pcre2.m4
@@ -0,0 +1,165 @@
+# ===========================================================================
+#      https://www.gnu.org/software/autoconf-archive/ax_check_pcre2.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CHECK_PCRE2([bits], [action-if-found], [action-if-not-found])
+#
+# DESCRIPTION
+#
+#   Search for an installed libpcre2-8 library. If nothing was specified
+#   when calling configure, it searches first in /usr/local and then in
+#   /usr, /opt/local and /sw. If the --with-pcre2=DIR is specified, it will
+#   try to find it in DIR/include/pcre2.h and DIR/lib/libpcre2-8. If
+#   --without-pcre2 is specified, the library is not searched at all.
+#
+#   If 'bits' is empty or '8', PCRE2 8-bit character support is checked
+#   only. If 'bits' contains '16', PCRE2 8-bit and 16-bit character support
+#   are checked. If 'bits' contains '32', PCRE2 8-bit and 32-bit character
+#   support are checked. When 'bits' contains both '16' and '32', PCRE2
+#   8-bit, 16-bit, and 32-bit character support is checked.
+#
+#   If either the header file (pcre2.h), or the library (libpcre2-8) is not
+#   found, or the specified PCRE2 character bit width is not supported,
+#   shell commands 'action-if-not-found' is run. If 'action-if-not-found' is
+#   not specified, the configuration exits on error, asking for a valid
+#   PCRE2 installation directory or --without-pcre2.
+#
+#   If both header file and library are found, and the specified PCRE2 bit
+#   widths are supported, shell commands 'action-if-found' is run. If
+#   'action-if-found' is not specified, the default action appends
+#   '-I${PCRE2_HOME}/include' to CPFLAGS, appends '-L$PCRE2_HOME}/lib' to
+#   LDFLAGS, prepends '-lpcre2-8' to LIBS, and calls AC_DEFINE(HAVE_PCRE2).
+#   You should use autoheader to include a definition for this symbol in a
+#   config.h file. Sample usage in a C/C++ source is as follows:
+#
+#     #ifdef HAVE_PCRE2
+#     #define PCRE2_CODE_UNIT_WIDTH 8
+#     #include <pcre2.h>
+#     #endif /* HAVE_PCRE2 */
+#
+# LICENSE
+#
+#   Copyright (c) 2020 Robert van Engelen <engelen@acm.org>
+#
+#   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 2 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 <https://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 2
+
+AC_DEFUN([AX_CHECK_PCRE2],
+#
+# Handle user hints
+#
+[AC_MSG_CHECKING(if PCRE2 is wanted)
+pcre2_places="/usr/local /usr /opt/local /sw"
+AC_ARG_WITH([pcre2],
+[  --with-pcre2=DIR        root directory path of PCRE2 installation @<:@defaults to
+                          /usr/local or /usr if not found in /usr/local@:>@
+  --without-pcre2         to disable PCRE2 usage completely],
+[if test "$withval" != "no" ; then
+  AC_MSG_RESULT(yes)
+  if test -d "$withval"
+  then
+    pcre2_places="$withval $pcre2_places"
+  else
+    AC_MSG_WARN([Sorry, $withval does not exist, checking usual places])
+  fi
+else
+  pcre2_places=""
+  AC_MSG_RESULT(no)
+fi],
+[AC_MSG_RESULT(yes)])
+#
+# Locate PCRE2, if wanted
+#
+if test -n "${pcre2_places}"
+then
+  # check the user supplied or any other more or less 'standard' place:
+  #   Most UNIX systems      : /usr/local and /usr
+  #   MacPorts / Fink on OSX : /opt/local respectively /sw
+  for PCRE2_HOME in ${pcre2_places} ; do
+    if test -f "${PCRE2_HOME}/include/pcre2.h"; then break; fi
+    PCRE2_HOME=""
+  done
+
+  PCRE2_OLD_LDFLAGS=$LDFLAGS
+  PCRE2_OLD_CPPFLAGS=$CPPFLAGS
+  if test -n "${PCRE2_HOME}"; then
+    LDFLAGS="$LDFLAGS -L${PCRE2_HOME}/lib"
+    CPPFLAGS="$CPPFLAGS -I${PCRE2_HOME}/include"
+  fi
+  AC_LANG_PUSH([C])
+  AC_CHECK_LIB([pcre2-8], [pcre2_compile_8], [pcre2_cv_libpcre2=yes], [pcre2_cv_libpcre2=no])
+  AC_CHECK_HEADER([pcre2.h], [pcre2_cv_pcre2_h=yes], [pcre2_cv_pcre2_h=no], [#define PCRE2_CODE_UNIT_WIDTH 8])
+  case "$1" in
+  *16*)
+    AC_CHECK_LIB([pcre2-16], [pcre2_compile_16], [pcre2_cv_libpcre2_16=yes], [pcre2_cv_libpcre2_16=no])
+    AC_CHECK_HEADER([pcre2.h], [pcre2_cv_pcre2_16_h=yes], [pcre2_cv_pcre2_16_h=no], [#define PCRE2_CODE_UNIT_WIDTH 16])
+    if test "$pcre2_cv_libpcre2_16" = "no" || test "$pcre2_cv_pcre2_16_h" = "no"; then
+      pcre2_cv_libpcre2=no
+    fi
+    ;;
+  esac
+  case "$1" in
+  *32*)
+    AC_CHECK_LIB([pcre2-32], [pcre2_compile_32], [pcre2_cv_libpcre2_32=yes], [pcre2_cv_libpcre2_32=no])
+    AC_CHECK_HEADER([pcre2.h], [pcre2_cv_pcre2_32_h=yes], [pcre2_cv_pcre2_32_h=no], [#define PCRE2_CODE_UNIT_WIDTH 32])
+    if test "$pcre2_cv_libpcre2_32" = "no" || test "$pcre2_cv_pcre2_32_h" = "no"; then
+      pcre2_cv_libpcre2=no
+    fi
+  esac
+  AC_LANG_POP([C])
+  if test "$pcre2_cv_libpcre2" = "yes" && test "$pcre2_cv_pcre2_h" = "yes"
+  then
+    #
+    # If both library and header were found, action-if-found
+    #
+    m4_ifblank([$2],[
+                if test -n "${PCRE2_HOME}"; then
+                  CPPFLAGS="$CPPFLAGS -I${PCRE2_HOME}/include"
+                  LDFLAGS="$LDFLAGS -L${PCRE2_HOME}/lib"
+                fi
+                LIBS="-lpcre2-8 $LIBS"
+                AC_DEFINE([HAVE_PCRE2], [1],
+                          [Define to 1 if you have `PCRE2' library (-lpcre2-$1)])
+               ],[
+                # Restore variables
+                LDFLAGS="$PCRE2_OLD_LDFLAGS"
+                CPPFLAGS="$PCRE2_OLD_CPPFLAGS"
+                $2
+               ])
+  else
+    #
+    # If either header or library was not found, action-if-not-found
+    #
+    m4_default([$3],[
+                AC_MSG_ERROR([either specify a valid PCRE2 installation with --with-pcre2=DIR or disable PCRE2 usage with --without-pcre2])
+                ])
+  fi
+fi
+])
diff --git a/m4/ax_code_coverage.m4 b/m4/ax_code_coverage.m4
new file mode 100644
index 0000000..53dcf7b
--- /dev/null
+++ b/m4/ax_code_coverage.m4
@@ -0,0 +1,272 @@
+# ===========================================================================
+#     https://www.gnu.org/software/autoconf-archive/ax_code_coverage.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CODE_COVERAGE()
+#
+# DESCRIPTION
+#
+#   Defines CODE_COVERAGE_CPPFLAGS, CODE_COVERAGE_CFLAGS,
+#   CODE_COVERAGE_CXXFLAGS and CODE_COVERAGE_LIBS which should be included
+#   in the CPPFLAGS, CFLAGS CXXFLAGS and LIBS/LIBADD variables of every
+#   build target (program or library) which should be built with code
+#   coverage support. Also add rules using AX_ADD_AM_MACRO_STATIC; and
+#   $enable_code_coverage which can be used in subsequent configure output.
+#   CODE_COVERAGE_ENABLED is defined and substituted, and corresponds to the
+#   value of the --enable-code-coverage option, which defaults to being
+#   disabled.
+#
+#   Test also for gcov program and create GCOV variable that could be
+#   substituted.
+#
+#   Note that all optimization flags in CFLAGS must be disabled when code
+#   coverage is enabled.
+#
+#   Usage example:
+#
+#   configure.ac:
+#
+#     AX_CODE_COVERAGE
+#
+#   Makefile.am:
+#
+#     include $(top_srcdir)/aminclude_static.am
+#
+#     my_program_LIBS = ... $(CODE_COVERAGE_LIBS) ...
+#     my_program_CPPFLAGS = ... $(CODE_COVERAGE_CPPFLAGS) ...
+#     my_program_CFLAGS = ... $(CODE_COVERAGE_CFLAGS) ...
+#     my_program_CXXFLAGS = ... $(CODE_COVERAGE_CXXFLAGS) ...
+#
+#     clean-local: code-coverage-clean
+#     distclean-local: code-coverage-dist-clean
+#
+#   This results in a "check-code-coverage" rule being added to any
+#   Makefile.am which do "include $(top_srcdir)/aminclude_static.am"
+#   (assuming the module has been configured with --enable-code-coverage).
+#   Running `make check-code-coverage` in that directory will run the
+#   module's test suite (`make check`) and build a code coverage report
+#   detailing the code which was touched, then print the URI for the report.
+#
+#   This code was derived from Makefile.decl in GLib, originally licensed
+#   under LGPLv2.1+.
+#
+# LICENSE
+#
+#   Copyright (c) 2012, 2016 Philip Withnall
+#   Copyright (c) 2012 Xan Lopez
+#   Copyright (c) 2012 Christian Persch
+#   Copyright (c) 2012 Paolo Borelli
+#   Copyright (c) 2012 Dan Winship
+#   Copyright (c) 2015,2018 Bastien ROUCARIES
+#
+#   This library is free software; you can redistribute it and/or modify it
+#   under the terms of the GNU Lesser General Public License as published by
+#   the Free Software Foundation; either version 2.1 of the License, or (at
+#   your option) any later version.
+#
+#   This library 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 Lesser
+#   General Public License for more details.
+#
+#   You should have received a copy of the GNU Lesser General Public License
+#   along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+#serial 34
+
+m4_define(_AX_CODE_COVERAGE_RULES,[
+AX_ADD_AM_MACRO_STATIC([
+# Code coverage
+#
+# Optional:
+#  - CODE_COVERAGE_DIRECTORY: Top-level directory for code coverage reporting.
+#    Multiple directories may be specified, separated by whitespace.
+#    (Default: \$(top_builddir))
+#  - CODE_COVERAGE_OUTPUT_FILE: Filename and path for the .info file generated
+#    by lcov for code coverage. (Default:
+#    \$(PACKAGE_NAME)-\$(PACKAGE_VERSION)-coverage.info)
+#  - CODE_COVERAGE_OUTPUT_DIRECTORY: Directory for generated code coverage
+#    reports to be created. (Default:
+#    \$(PACKAGE_NAME)-\$(PACKAGE_VERSION)-coverage)
+#  - CODE_COVERAGE_BRANCH_COVERAGE: Set to 1 to enforce branch coverage,
+#    set to 0 to disable it and leave empty to stay with the default.
+#    (Default: empty)
+#  - CODE_COVERAGE_LCOV_SHOPTS_DEFAULT: Extra options shared between both lcov
+#    instances. (Default: based on $CODE_COVERAGE_BRANCH_COVERAGE)
+#  - CODE_COVERAGE_LCOV_SHOPTS: Extra options to shared between both lcov
+#    instances. (Default: $CODE_COVERAGE_LCOV_SHOPTS_DEFAULT)
+#  - CODE_COVERAGE_LCOV_OPTIONS_GCOVPATH: --gcov-tool pathtogcov
+#  - CODE_COVERAGE_LCOV_OPTIONS_DEFAULT: Extra options to pass to the
+#    collecting lcov instance. (Default: $CODE_COVERAGE_LCOV_OPTIONS_GCOVPATH)
+#  - CODE_COVERAGE_LCOV_OPTIONS: Extra options to pass to the collecting lcov
+#    instance. (Default: $CODE_COVERAGE_LCOV_OPTIONS_DEFAULT)
+#  - CODE_COVERAGE_LCOV_RMOPTS_DEFAULT: Extra options to pass to the filtering
+#    lcov instance. (Default: empty)
+#  - CODE_COVERAGE_LCOV_RMOPTS: Extra options to pass to the filtering lcov
+#    instance. (Default: $CODE_COVERAGE_LCOV_RMOPTS_DEFAULT)
+#  - CODE_COVERAGE_GENHTML_OPTIONS_DEFAULT: Extra options to pass to the
+#    genhtml instance. (Default: based on $CODE_COVERAGE_BRANCH_COVERAGE)
+#  - CODE_COVERAGE_GENHTML_OPTIONS: Extra options to pass to the genhtml
+#    instance. (Default: $CODE_COVERAGE_GENHTML_OPTIONS_DEFAULT)
+#  - CODE_COVERAGE_IGNORE_PATTERN: Extra glob pattern of files to ignore
+#
+# The generated report will be titled using the \$(PACKAGE_NAME) and
+# \$(PACKAGE_VERSION). In order to add the current git hash to the title,
+# use the git-version-gen script, available online.
+# Optional variables
+# run only on top dir
+if CODE_COVERAGE_ENABLED
+ ifeq (\$(abs_builddir), \$(abs_top_builddir))
+CODE_COVERAGE_DIRECTORY ?= \$(top_builddir)
+CODE_COVERAGE_OUTPUT_FILE ?= \$(PACKAGE_NAME)-\$(PACKAGE_VERSION)-coverage.info
+CODE_COVERAGE_OUTPUT_DIRECTORY ?= \$(PACKAGE_NAME)-\$(PACKAGE_VERSION)-coverage
+
+CODE_COVERAGE_BRANCH_COVERAGE ?=
+CODE_COVERAGE_LCOV_SHOPTS_DEFAULT ?= \$(if \$(CODE_COVERAGE_BRANCH_COVERAGE),\
+--rc lcov_branch_coverage=\$(CODE_COVERAGE_BRANCH_COVERAGE))
+CODE_COVERAGE_LCOV_SHOPTS ?= \$(CODE_COVERAGE_LCOV_SHOPTS_DEFAULT)
+CODE_COVERAGE_LCOV_OPTIONS_GCOVPATH ?= --gcov-tool \"\$(GCOV)\"
+CODE_COVERAGE_LCOV_OPTIONS_DEFAULT ?= \$(CODE_COVERAGE_LCOV_OPTIONS_GCOVPATH)
+CODE_COVERAGE_LCOV_OPTIONS ?= \$(CODE_COVERAGE_LCOV_OPTIONS_DEFAULT)
+CODE_COVERAGE_LCOV_RMOPTS_DEFAULT ?=
+CODE_COVERAGE_LCOV_RMOPTS ?= \$(CODE_COVERAGE_LCOV_RMOPTS_DEFAULT)
+CODE_COVERAGE_GENHTML_OPTIONS_DEFAULT ?=\
+\$(if \$(CODE_COVERAGE_BRANCH_COVERAGE),\
+--rc genhtml_branch_coverage=\$(CODE_COVERAGE_BRANCH_COVERAGE))
+CODE_COVERAGE_GENHTML_OPTIONS ?= \$(CODE_COVERAGE_GENHTML_OPTIONS_DEFAULT)
+CODE_COVERAGE_IGNORE_PATTERN ?=
+
+GITIGNOREFILES := \$(GITIGNOREFILES) \$(CODE_COVERAGE_OUTPUT_FILE) \$(CODE_COVERAGE_OUTPUT_DIRECTORY)
+code_coverage_v_lcov_cap = \$(code_coverage_v_lcov_cap_\$(V))
+code_coverage_v_lcov_cap_ = \$(code_coverage_v_lcov_cap_\$(AM_DEFAULT_VERBOSITY))
+code_coverage_v_lcov_cap_0 = @echo \"  LCOV   --capture\" \$(CODE_COVERAGE_OUTPUT_FILE);
+code_coverage_v_lcov_ign = \$(code_coverage_v_lcov_ign_\$(V))
+code_coverage_v_lcov_ign_ = \$(code_coverage_v_lcov_ign_\$(AM_DEFAULT_VERBOSITY))
+code_coverage_v_lcov_ign_0 = @echo \"  LCOV   --remove /tmp/*\" \$(CODE_COVERAGE_IGNORE_PATTERN);
+code_coverage_v_genhtml = \$(code_coverage_v_genhtml_\$(V))
+code_coverage_v_genhtml_ = \$(code_coverage_v_genhtml_\$(AM_DEFAULT_VERBOSITY))
+code_coverage_v_genhtml_0 = @echo \"  GEN   \" \"\$(CODE_COVERAGE_OUTPUT_DIRECTORY)\";
+code_coverage_quiet = \$(code_coverage_quiet_\$(V))
+code_coverage_quiet_ = \$(code_coverage_quiet_\$(AM_DEFAULT_VERBOSITY))
+code_coverage_quiet_0 = --quiet
+
+# sanitizes the test-name: replaces with underscores: dashes and dots
+code_coverage_sanitize = \$(subst -,_,\$(subst .,_,\$(1)))
+
+# Use recursive makes in order to ignore errors during check
+check-code-coverage:
+	-\$(AM_V_at)\$(MAKE) \$(AM_MAKEFLAGS) -k check
+	\$(AM_V_at)\$(MAKE) \$(AM_MAKEFLAGS) code-coverage-capture
+
+# Capture code coverage data
+code-coverage-capture: code-coverage-capture-hook
+	\$(code_coverage_v_lcov_cap)\$(LCOV) \$(code_coverage_quiet) \$(addprefix --directory ,\$(CODE_COVERAGE_DIRECTORY)) --capture --output-file \"\$(CODE_COVERAGE_OUTPUT_FILE).tmp\" --test-name \"\$(call code_coverage_sanitize,\$(PACKAGE_NAME)-\$(PACKAGE_VERSION))\" --no-checksum --compat-libtool \$(CODE_COVERAGE_LCOV_SHOPTS) \$(CODE_COVERAGE_LCOV_OPTIONS)
+	\$(code_coverage_v_lcov_ign)\$(LCOV) \$(code_coverage_quiet) \$(addprefix --directory ,\$(CODE_COVERAGE_DIRECTORY)) --remove \"\$(CODE_COVERAGE_OUTPUT_FILE).tmp\" \"/tmp/*\" \$(CODE_COVERAGE_IGNORE_PATTERN) --output-file \"\$(CODE_COVERAGE_OUTPUT_FILE)\" \$(CODE_COVERAGE_LCOV_SHOPTS) \$(CODE_COVERAGE_LCOV_RMOPTS)
+	-@rm -f \"\$(CODE_COVERAGE_OUTPUT_FILE).tmp\"
+	\$(code_coverage_v_genhtml)LANG=C \$(GENHTML) \$(code_coverage_quiet) \$(addprefix --prefix ,\$(CODE_COVERAGE_DIRECTORY)) --output-directory \"\$(CODE_COVERAGE_OUTPUT_DIRECTORY)\" --title \"\$(PACKAGE_NAME)-\$(PACKAGE_VERSION) Code Coverage\" --legend --show-details \"\$(CODE_COVERAGE_OUTPUT_FILE)\" \$(CODE_COVERAGE_GENHTML_OPTIONS)
+	@echo \"file://\$(abs_builddir)/\$(CODE_COVERAGE_OUTPUT_DIRECTORY)/index.html\"
+
+code-coverage-clean:
+	-\$(LCOV) --directory \$(top_builddir) -z
+	-rm -rf \"\$(CODE_COVERAGE_OUTPUT_FILE)\" \"\$(CODE_COVERAGE_OUTPUT_FILE).tmp\" \"\$(CODE_COVERAGE_OUTPUT_DIRECTORY)\"
+	-find . \\( -name \"*.gcda\" -o -name \"*.gcno\" -o -name \"*.gcov\" \\) -delete
+
+code-coverage-dist-clean:
+
+A][M_DISTCHECK_CONFIGURE_FLAGS := \$(A][M_DISTCHECK_CONFIGURE_FLAGS) --disable-code-coverage
+ else # ifneq (\$(abs_builddir), \$(abs_top_builddir))
+check-code-coverage:
+
+code-coverage-capture: code-coverage-capture-hook
+
+code-coverage-clean:
+
+code-coverage-dist-clean:
+ endif # ifeq (\$(abs_builddir), \$(abs_top_builddir))
+else #! CODE_COVERAGE_ENABLED
+# Use recursive makes in order to ignore errors during check
+check-code-coverage:
+	@echo \"Need to reconfigure with --enable-code-coverage\"
+# Capture code coverage data
+code-coverage-capture: code-coverage-capture-hook
+	@echo \"Need to reconfigure with --enable-code-coverage\"
+
+code-coverage-clean:
+
+code-coverage-dist-clean:
+
+endif #CODE_COVERAGE_ENABLED
+# Hook rule executed before code-coverage-capture, overridable by the user
+code-coverage-capture-hook:
+
+.PHONY: check-code-coverage code-coverage-capture code-coverage-dist-clean code-coverage-clean code-coverage-capture-hook
+])
+])
+
+AC_DEFUN([_AX_CODE_COVERAGE_ENABLED],[
+	AX_CHECK_GNU_MAKE([],[AC_MSG_ERROR([not using GNU make that is needed for coverage])])
+	AC_REQUIRE([AX_ADD_AM_MACRO_STATIC])
+	# check for gcov
+	AC_CHECK_TOOL([GCOV],
+		  [$_AX_CODE_COVERAGE_GCOV_PROG_WITH],
+		  [:])
+	AS_IF([test "X$GCOV" = "X:"],
+	      [AC_MSG_ERROR([gcov is needed to do coverage])])
+	AC_SUBST([GCOV])
+
+	dnl Check if gcc is being used
+	AS_IF([ test "$GCC" = "no" ], [
+		AC_MSG_ERROR([not compiling with gcc, which is required for gcov code coverage])
+	      ])
+
+	AC_CHECK_PROG([LCOV], [lcov], [lcov])
+	AC_CHECK_PROG([GENHTML], [genhtml], [genhtml])
+
+	AS_IF([ test x"$LCOV" = x ], [
+		AC_MSG_ERROR([To enable code coverage reporting you must have lcov installed])
+	      ])
+
+	AS_IF([ test x"$GENHTML" = x ], [
+		AC_MSG_ERROR([Could not find genhtml from the lcov package])
+	])
+
+	dnl Build the code coverage flags
+	dnl Define CODE_COVERAGE_LDFLAGS for backwards compatibility
+	CODE_COVERAGE_CPPFLAGS="-DNDEBUG"
+	CODE_COVERAGE_CFLAGS="-O0 -g -fprofile-arcs -ftest-coverage -fprofile-abs-path"
+	CODE_COVERAGE_CXXFLAGS="-O0 -g -fprofile-arcs -ftest-coverage -fprofile-abs-path"
+	CODE_COVERAGE_LIBS="-lgcov"
+
+	AC_SUBST([CODE_COVERAGE_CPPFLAGS])
+	AC_SUBST([CODE_COVERAGE_CFLAGS])
+	AC_SUBST([CODE_COVERAGE_CXXFLAGS])
+	AC_SUBST([CODE_COVERAGE_LIBS])
+])
+
+AC_DEFUN([AX_CODE_COVERAGE],[
+	dnl Check for --enable-code-coverage
+
+	# allow to override gcov location
+	AC_ARG_WITH([gcov],
+	  [AS_HELP_STRING([--with-gcov[=GCOV]], [use given GCOV for coverage (GCOV=gcov).])],
+	  [_AX_CODE_COVERAGE_GCOV_PROG_WITH=$with_gcov],
+	  [_AX_CODE_COVERAGE_GCOV_PROG_WITH=gcov])
+
+	AC_MSG_CHECKING([whether to build with code coverage support])
+	AC_ARG_ENABLE([code-coverage],
+	  AS_HELP_STRING([--enable-code-coverage],
+	  [Whether to enable code coverage support]),,
+	  enable_code_coverage=no)
+
+	AM_CONDITIONAL([CODE_COVERAGE_ENABLED], [test "x$enable_code_coverage" = xyes])
+	AC_SUBST([CODE_COVERAGE_ENABLED], [$enable_code_coverage])
+	AC_MSG_RESULT($enable_code_coverage)
+
+	AS_IF([ test "x$enable_code_coverage" = xyes ], [
+		_AX_CODE_COVERAGE_ENABLED
+	      ])
+
+	_AX_CODE_COVERAGE_RULES
+])
diff --git a/m4/ax_cxx_compile_stdcxx.m4 b/m4/ax_cxx_compile_stdcxx.m4
new file mode 100644
index 0000000..9413da6
--- /dev/null
+++ b/m4/ax_cxx_compile_stdcxx.m4
@@ -0,0 +1,962 @@
+# ===========================================================================
+#  https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_CXX_COMPILE_STDCXX(VERSION, [ext|noext], [mandatory|optional])
+#
+# DESCRIPTION
+#
+#   Check for baseline language coverage in the compiler for the specified
+#   version of the C++ standard.  If necessary, add switches to CXX and
+#   CXXCPP to enable support.  VERSION may be '11' (for the C++11 standard)
+#   or '14' (for the C++14 standard).
+#
+#   The second argument, if specified, indicates whether you insist on an
+#   extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g.
+#   -std=c++11).  If neither is specified, you get whatever works, with
+#   preference for no added switch, and then for an extended mode.
+#
+#   The third argument, if specified 'mandatory' or if left unspecified,
+#   indicates that baseline support for the specified C++ standard is
+#   required and that the macro should error out if no mode with that
+#   support is found.  If specified 'optional', then configuration proceeds
+#   regardless, after defining HAVE_CXX${VERSION} 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>
+#   Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <sokolov@google.com>
+#   Copyright (c) 2015 Paul Norman <penorman@mac.com>
+#   Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu>
+#   Copyright (c) 2016, 2018 Krzesimir Nowak <qdlacz@gmail.com>
+#   Copyright (c) 2019 Enji Cooper <yaneurabeya@gmail.com>
+#   Copyright (c) 2020 Jason Merrill <jason@redhat.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 12
+
+dnl  This macro is based on the code from the AX_CXX_COMPILE_STDCXX_11 macro
+dnl  (serial version number 13).
+
+AC_DEFUN([AX_CXX_COMPILE_STDCXX], [dnl
+  m4_if([$1], [11], [ax_cxx_compile_alternatives="11 0x"],
+        [$1], [14], [ax_cxx_compile_alternatives="14 1y"],
+        [$1], [17], [ax_cxx_compile_alternatives="17 1z"],
+        [m4_fatal([invalid first argument `$1' to AX_CXX_COMPILE_STDCXX])])dnl
+  m4_if([$2], [], [],
+        [$2], [ext], [],
+        [$2], [noext], [],
+        [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX])])dnl
+  m4_if([$3], [], [ax_cxx_compile_cxx$1_required=true],
+        [$3], [mandatory], [ax_cxx_compile_cxx$1_required=true],
+        [$3], [optional], [ax_cxx_compile_cxx$1_required=false],
+        [m4_fatal([invalid third argument `$3' to AX_CXX_COMPILE_STDCXX])])
+  AC_LANG_PUSH([C++])dnl
+  ac_success=no
+
+  m4_if([$2], [], [dnl
+    AC_CACHE_CHECK(whether $CXX supports C++$1 features by default,
+		   ax_cv_cxx_compile_cxx$1,
+      [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
+        [ax_cv_cxx_compile_cxx$1=yes],
+        [ax_cv_cxx_compile_cxx$1=no])])
+    if test x$ax_cv_cxx_compile_cxx$1 = xyes; then
+      ac_success=yes
+    fi])
+
+  m4_if([$2], [noext], [], [dnl
+  if test x$ac_success = xno; then
+    for alternative in ${ax_cxx_compile_alternatives}; do
+      switch="-std=gnu++${alternative}"
+      cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
+      AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch,
+                     $cachevar,
+        [ac_save_CXX="$CXX"
+         CXX="$CXX $switch"
+         AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
+          [eval $cachevar=yes],
+          [eval $cachevar=no])
+         CXX="$ac_save_CXX"])
+      if eval test x\$$cachevar = xyes; then
+        CXX="$CXX $switch"
+        if test -n "$CXXCPP" ; then
+          CXXCPP="$CXXCPP $switch"
+        fi
+        ac_success=yes
+        break
+      fi
+    done
+  fi])
+
+  m4_if([$2], [ext], [], [dnl
+  if test x$ac_success = xno; then
+    dnl HP's aCC needs +std=c++11 according to:
+    dnl http://h21007.www2.hp.com/portal/download/files/unprot/aCxx/PDF_Release_Notes/769149-001.pdf
+    dnl Cray's crayCC needs "-h std=c++11"
+    for alternative in ${ax_cxx_compile_alternatives}; do
+      for switch in -std=c++${alternative} +std=c++${alternative} "-h std=c++${alternative}"; do
+        cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch])
+        AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch,
+                       $cachevar,
+          [ac_save_CXX="$CXX"
+           CXX="$CXX $switch"
+           AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])],
+            [eval $cachevar=yes],
+            [eval $cachevar=no])
+           CXX="$ac_save_CXX"])
+        if eval test x\$$cachevar = xyes; then
+          CXX="$CXX $switch"
+          if test -n "$CXXCPP" ; then
+            CXXCPP="$CXXCPP $switch"
+          fi
+          ac_success=yes
+          break
+        fi
+      done
+      if test x$ac_success = xyes; then
+        break
+      fi
+    done
+  fi])
+  AC_LANG_POP([C++])
+  if test x$ax_cxx_compile_cxx$1_required = xtrue; then
+    if test x$ac_success = xno; then
+      AC_MSG_ERROR([*** A compiler with support for C++$1 language features is required.])
+    fi
+  fi
+  if test x$ac_success = xno; then
+    HAVE_CXX$1=0
+    AC_MSG_NOTICE([No compiler with C++$1 support was found])
+  else
+    HAVE_CXX$1=1
+    AC_DEFINE(HAVE_CXX$1,1,
+              [define if the compiler supports basic C++$1 syntax])
+  fi
+  AC_SUBST(HAVE_CXX$1)
+])
+
+
+dnl  Test body for checking C++11 support
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_11],
+  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
+)
+
+
+dnl  Test body for checking C++14 support
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_14],
+  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
+  _AX_CXX_COMPILE_STDCXX_testbody_new_in_14
+)
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_17],
+  _AX_CXX_COMPILE_STDCXX_testbody_new_in_11
+  _AX_CXX_COMPILE_STDCXX_testbody_new_in_14
+  _AX_CXX_COMPILE_STDCXX_testbody_new_in_17
+)
+
+dnl  Tests for new features in C++11
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_11], [[
+
+// If the compiler admits that it is not ready for C++11, why torture it?
+// Hopefully, this will speed up the test.
+
+#ifndef __cplusplus
+
+#error "This is not a C++ compiler"
+
+#elif __cplusplus < 201103L
+
+#error "This is not a C++11 compiler"
+
+#else
+
+namespace cxx11
+{
+
+  namespace test_static_assert
+  {
+
+    template <typename T>
+    struct check
+    {
+      static_assert(sizeof(int) <= sizeof(T), "not big enough");
+    };
+
+  }
+
+  namespace test_final_override
+  {
+
+    struct Base
+    {
+      virtual ~Base() {}
+      virtual void f() {}
+    };
+
+    struct Derived : public Base
+    {
+      virtual ~Derived() override {}
+      virtual void f() override {}
+    };
+
+  }
+
+  namespace test_double_right_angle_brackets
+  {
+
+    template < typename T >
+    struct check {};
+
+    typedef check<void> single_type;
+    typedef check<check<void>> double_type;
+    typedef check<check<check<void>>> triple_type;
+    typedef check<check<check<check<void>>>> quadruple_type;
+
+  }
+
+  namespace test_decltype
+  {
+
+    int
+    f()
+    {
+      int a = 1;
+      decltype(a) b = 2;
+      return a + b;
+    }
+
+  }
+
+  namespace test_type_deduction
+  {
+
+    template < typename T1, typename T2 >
+    struct is_same
+    {
+      static const bool value = false;
+    };
+
+    template < typename T >
+    struct is_same<T, T>
+    {
+      static const bool value = true;
+    };
+
+    template < typename T1, typename T2 >
+    auto
+    add(T1 a1, T2 a2) -> decltype(a1 + a2)
+    {
+      return a1 + a2;
+    }
+
+    int
+    test(const int c, volatile int v)
+    {
+      static_assert(is_same<int, decltype(0)>::value == true, "");
+      static_assert(is_same<int, decltype(c)>::value == false, "");
+      static_assert(is_same<int, decltype(v)>::value == false, "");
+      auto ac = c;
+      auto av = v;
+      auto sumi = ac + av + 'x';
+      auto sumf = ac + av + 1.0;
+      static_assert(is_same<int, decltype(ac)>::value == true, "");
+      static_assert(is_same<int, decltype(av)>::value == true, "");
+      static_assert(is_same<int, decltype(sumi)>::value == true, "");
+      static_assert(is_same<int, decltype(sumf)>::value == false, "");
+      static_assert(is_same<int, decltype(add(c, v))>::value == true, "");
+      return (sumf > 0.0) ? sumi : add(c, v);
+    }
+
+  }
+
+  namespace test_noexcept
+  {
+
+    int f() { return 0; }
+    int g() noexcept { return 0; }
+
+    static_assert(noexcept(f()) == false, "");
+    static_assert(noexcept(g()) == true, "");
+
+  }
+
+  namespace test_constexpr
+  {
+
+    template < typename CharT >
+    unsigned long constexpr
+    strlen_c_r(const CharT *const s, const unsigned long acc) noexcept
+    {
+      return *s ? strlen_c_r(s + 1, acc + 1) : acc;
+    }
+
+    template < typename CharT >
+    unsigned long constexpr
+    strlen_c(const CharT *const s) noexcept
+    {
+      return strlen_c_r(s, 0UL);
+    }
+
+    static_assert(strlen_c("") == 0UL, "");
+    static_assert(strlen_c("1") == 1UL, "");
+    static_assert(strlen_c("example") == 7UL, "");
+    static_assert(strlen_c("another\0example") == 7UL, "");
+
+  }
+
+  namespace test_rvalue_references
+  {
+
+    template < int N >
+    struct answer
+    {
+      static constexpr int value = N;
+    };
+
+    answer<1> f(int&)       { return answer<1>(); }
+    answer<2> f(const int&) { return answer<2>(); }
+    answer<3> f(int&&)      { return answer<3>(); }
+
+    void
+    test()
+    {
+      int i = 0;
+      const int c = 0;
+      static_assert(decltype(f(i))::value == 1, "");
+      static_assert(decltype(f(c))::value == 2, "");
+      static_assert(decltype(f(0))::value == 3, "");
+    }
+
+  }
+
+  namespace test_uniform_initialization
+  {
+
+    struct test
+    {
+      static const int zero {};
+      static const int one {1};
+    };
+
+    static_assert(test::zero == 0, "");
+    static_assert(test::one == 1, "");
+
+  }
+
+  namespace test_lambdas
+  {
+
+    void
+    test1()
+    {
+      auto lambda1 = [](){};
+      auto lambda2 = lambda1;
+      lambda1();
+      lambda2();
+    }
+
+    int
+    test2()
+    {
+      auto a = [](int i, int j){ return i + j; }(1, 2);
+      auto b = []() -> int { return '0'; }();
+      auto c = [=](){ return a + b; }();
+      auto d = [&](){ return c; }();
+      auto e = [a, &b](int x) mutable {
+        const auto identity = [](int y){ return y; };
+        for (auto i = 0; i < a; ++i)
+          a += b--;
+        return x + identity(a + b);
+      }(0);
+      return a + b + c + d + e;
+    }
+
+    int
+    test3()
+    {
+      const auto nullary = [](){ return 0; };
+      const auto unary = [](int x){ return x; };
+      using nullary_t = decltype(nullary);
+      using unary_t = decltype(unary);
+      const auto higher1st = [](nullary_t f){ return f(); };
+      const auto higher2nd = [unary](nullary_t f1){
+        return [unary, f1](unary_t f2){ return f2(unary(f1())); };
+      };
+      return higher1st(nullary) + higher2nd(nullary)(unary);
+    }
+
+  }
+
+  namespace test_variadic_templates
+  {
+
+    template <int...>
+    struct sum;
+
+    template <int N0, int... N1toN>
+    struct sum<N0, N1toN...>
+    {
+      static constexpr auto value = N0 + sum<N1toN...>::value;
+    };
+
+    template <>
+    struct sum<>
+    {
+      static constexpr auto value = 0;
+    };
+
+    static_assert(sum<>::value == 0, "");
+    static_assert(sum<1>::value == 1, "");
+    static_assert(sum<23>::value == 23, "");
+    static_assert(sum<1, 2>::value == 3, "");
+    static_assert(sum<5, 5, 11>::value == 21, "");
+    static_assert(sum<2, 3, 5, 7, 11, 13>::value == 41, "");
+
+  }
+
+  // http://stackoverflow.com/questions/13728184/template-aliases-and-sfinae
+  // Clang 3.1 fails with headers of libstd++ 4.8.3 when using std::function
+  // because of this.
+  namespace test_template_alias_sfinae
+  {
+
+    struct foo {};
+
+    template<typename T>
+    using member = typename T::member_type;
+
+    template<typename T>
+    void func(...) {}
+
+    template<typename T>
+    void func(member<T>*) {}
+
+    void test();
+
+    void test() { func<foo>(0); }
+
+  }
+
+}  // namespace cxx11
+
+#endif  // __cplusplus >= 201103L
+
+]])
+
+
+dnl  Tests for new features in C++14
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_14], [[
+
+// If the compiler admits that it is not ready for C++14, why torture it?
+// Hopefully, this will speed up the test.
+
+#ifndef __cplusplus
+
+#error "This is not a C++ compiler"
+
+#elif __cplusplus < 201402L
+
+#error "This is not a C++14 compiler"
+
+#else
+
+namespace cxx14
+{
+
+  namespace test_polymorphic_lambdas
+  {
+
+    int
+    test()
+    {
+      const auto lambda = [](auto&&... args){
+        const auto istiny = [](auto x){
+          return (sizeof(x) == 1UL) ? 1 : 0;
+        };
+        const int aretiny[] = { istiny(args)... };
+        return aretiny[0];
+      };
+      return lambda(1, 1L, 1.0f, '1');
+    }
+
+  }
+
+  namespace test_binary_literals
+  {
+
+    constexpr auto ivii = 0b0000000000101010;
+    static_assert(ivii == 42, "wrong value");
+
+  }
+
+  namespace test_generalized_constexpr
+  {
+
+    template < typename CharT >
+    constexpr unsigned long
+    strlen_c(const CharT *const s) noexcept
+    {
+      auto length = 0UL;
+      for (auto p = s; *p; ++p)
+        ++length;
+      return length;
+    }
+
+    static_assert(strlen_c("") == 0UL, "");
+    static_assert(strlen_c("x") == 1UL, "");
+    static_assert(strlen_c("test") == 4UL, "");
+    static_assert(strlen_c("another\0test") == 7UL, "");
+
+  }
+
+  namespace test_lambda_init_capture
+  {
+
+    int
+    test()
+    {
+      auto x = 0;
+      const auto lambda1 = [a = x](int b){ return a + b; };
+      const auto lambda2 = [a = lambda1(x)](){ return a; };
+      return lambda2();
+    }
+
+  }
+
+  namespace test_digit_separators
+  {
+
+    constexpr auto ten_million = 100'000'000;
+    static_assert(ten_million == 100000000, "");
+
+  }
+
+  namespace test_return_type_deduction
+  {
+
+    auto f(int& x) { return x; }
+    decltype(auto) g(int& x) { return x; }
+
+    template < typename T1, typename T2 >
+    struct is_same
+    {
+      static constexpr auto value = false;
+    };
+
+    template < typename T >
+    struct is_same<T, T>
+    {
+      static constexpr auto value = true;
+    };
+
+    int
+    test()
+    {
+      auto x = 0;
+      static_assert(is_same<int, decltype(f(x))>::value, "");
+      static_assert(is_same<int&, decltype(g(x))>::value, "");
+      return x;
+    }
+
+  }
+
+}  // namespace cxx14
+
+#endif  // __cplusplus >= 201402L
+
+]])
+
+
+dnl  Tests for new features in C++17
+
+m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_17], [[
+
+// If the compiler admits that it is not ready for C++17, why torture it?
+// Hopefully, this will speed up the test.
+
+#ifndef __cplusplus
+
+#error "This is not a C++ compiler"
+
+#elif __cplusplus < 201703L
+
+#error "This is not a C++17 compiler"
+
+#else
+
+#include <initializer_list>
+#include <utility>
+#include <type_traits>
+
+namespace cxx17
+{
+
+  namespace test_constexpr_lambdas
+  {
+
+    constexpr int foo = [](){return 42;}();
+
+  }
+
+  namespace test::nested_namespace::definitions
+  {
+
+  }
+
+  namespace test_fold_expression
+  {
+
+    template<typename... Args>
+    int multiply(Args... args)
+    {
+      return (args * ... * 1);
+    }
+
+    template<typename... Args>
+    bool all(Args... args)
+    {
+      return (args && ...);
+    }
+
+  }
+
+  namespace test_extended_static_assert
+  {
+
+    static_assert (true);
+
+  }
+
+  namespace test_auto_brace_init_list
+  {
+
+    auto foo = {5};
+    auto bar {5};
+
+    static_assert(std::is_same<std::initializer_list<int>, decltype(foo)>::value);
+    static_assert(std::is_same<int, decltype(bar)>::value);
+  }
+
+  namespace test_typename_in_template_template_parameter
+  {
+
+    template<template<typename> typename X> struct D;
+
+  }
+
+  namespace test_fallthrough_nodiscard_maybe_unused_attributes
+  {
+
+    int f1()
+    {
+      return 42;
+    }
+
+    [[nodiscard]] int f2()
+    {
+      [[maybe_unused]] auto unused = f1();
+
+      switch (f1())
+      {
+      case 17:
+        f1();
+        [[fallthrough]];
+      case 42:
+        f1();
+      }
+      return f1();
+    }
+
+  }
+
+  namespace test_extended_aggregate_initialization
+  {
+
+    struct base1
+    {
+      int b1, b2 = 42;
+    };
+
+    struct base2
+    {
+      base2() {
+        b3 = 42;
+      }
+      int b3;
+    };
+
+    struct derived : base1, base2
+    {
+        int d;
+    };
+
+    derived d1 {{1, 2}, {}, 4};  // full initialization
+    derived d2 {{}, {}, 4};      // value-initialized bases
+
+  }
+
+  namespace test_general_range_based_for_loop
+  {
+
+    struct iter
+    {
+      int i;
+
+      int& operator* ()
+      {
+        return i;
+      }
+
+      const int& operator* () const
+      {
+        return i;
+      }
+
+      iter& operator++()
+      {
+        ++i;
+        return *this;
+      }
+    };
+
+    struct sentinel
+    {
+      int i;
+    };
+
+    bool operator== (const iter& i, const sentinel& s)
+    {
+      return i.i == s.i;
+    }
+
+    bool operator!= (const iter& i, const sentinel& s)
+    {
+      return !(i == s);
+    }
+
+    struct range
+    {
+      iter begin() const
+      {
+        return {0};
+      }
+
+      sentinel end() const
+      {
+        return {5};
+      }
+    };
+
+    void f()
+    {
+      range r {};
+
+      for (auto i : r)
+      {
+        [[maybe_unused]] auto v = i;
+      }
+    }
+
+  }
+
+  namespace test_lambda_capture_asterisk_this_by_value
+  {
+
+    struct t
+    {
+      int i;
+      int foo()
+      {
+        return [*this]()
+        {
+          return i;
+        }();
+      }
+    };
+
+  }
+
+  namespace test_enum_class_construction
+  {
+
+    enum class byte : unsigned char
+    {};
+
+    byte foo {42};
+
+  }
+
+  namespace test_constexpr_if
+  {
+
+    template <bool cond>
+    int f ()
+    {
+      if constexpr(cond)
+      {
+        return 13;
+      }
+      else
+      {
+        return 42;
+      }
+    }
+
+  }
+
+  namespace test_selection_statement_with_initializer
+  {
+
+    int f()
+    {
+      return 13;
+    }
+
+    int f2()
+    {
+      if (auto i = f(); i > 0)
+      {
+        return 3;
+      }
+
+      switch (auto i = f(); i + 4)
+      {
+      case 17:
+        return 2;
+
+      default:
+        return 1;
+      }
+    }
+
+  }
+
+  namespace test_template_argument_deduction_for_class_templates
+  {
+
+    template <typename T1, typename T2>
+    struct pair
+    {
+      pair (T1 p1, T2 p2)
+        : m1 {p1},
+          m2 {p2}
+      {}
+
+      T1 m1;
+      T2 m2;
+    };
+
+    void f()
+    {
+      [[maybe_unused]] auto p = pair{13, 42u};
+    }
+
+  }
+
+  namespace test_non_type_auto_template_parameters
+  {
+
+    template <auto n>
+    struct B
+    {};
+
+    B<5> b1;
+    B<'a'> b2;
+
+  }
+
+  namespace test_structured_bindings
+  {
+
+    int arr[2] = { 1, 2 };
+    std::pair<int, int> pr = { 1, 2 };
+
+    auto f1() -> int(&)[2]
+    {
+      return arr;
+    }
+
+    auto f2() -> std::pair<int, int>&
+    {
+      return pr;
+    }
+
+    struct S
+    {
+      int x1 : 2;
+      volatile double y1;
+    };
+
+    S f3()
+    {
+      return {};
+    }
+
+    auto [ x1, y1 ] = f1();
+    auto& [ xr1, yr1 ] = f1();
+    auto [ x2, y2 ] = f2();
+    auto& [ xr2, yr2 ] = f2();
+    const auto [ x3, y3 ] = f3();
+
+  }
+
+  namespace test_exception_spec_type_system
+  {
+
+    struct Good {};
+    struct Bad {};
+
+    void g1() noexcept;
+    void g2();
+
+    template<typename T>
+    Bad
+    f(T*, T*);
+
+    template<typename T1, typename T2>
+    Good
+    f(T1*, T2*);
+
+    static_assert (std::is_same_v<Good, decltype(f(g1, g2))>);
+
+  }
+
+  namespace test_inline_variables
+  {
+
+    template<class T> void f(T)
+    {}
+
+    template<class T> inline T g(T)
+    {
+      return T{};
+    }
+
+    template<> inline void f<>(int)
+    {}
+
+    template<> int g<>(int)
+    {
+      return 5;
+    }
+
+  }
+
+}  // namespace cxx17
+
+#endif  // __cplusplus < 201703L
+
+]])
diff --git a/m4/ax_cxx_compile_stdcxx_11.m4 b/m4/ax_cxx_compile_stdcxx_11.m4
new file mode 100644
index 0000000..0aadeaf
--- /dev/null
+++ b/m4/ax_cxx_compile_stdcxx_11.m4
@@ -0,0 +1,39 @@
+# ============================================================================
+#  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 CXX and CXXCPP to enable
+#   support.
+#
+#   This macro is a convenience alias for calling the AX_CXX_COMPILE_STDCXX
+#   macro with the version set to C++11.  The two optional arguments are
+#   forwarded literally as the second and third argument respectively.
+#   Please see the documentation for the AX_CXX_COMPILE_STDCXX macro for
+#   more information.  If you want to use this macro, you also need to
+#   download the ax_cxx_compile_stdcxx.m4 file.
+#
+# 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>
+#   Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov <sokolov@google.com>
+#   Copyright (c) 2015 Paul Norman <penorman@mac.com>
+#   Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu>
+#
+#   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 17
+
+AX_REQUIRE_DEFINED([AX_CXX_COMPILE_STDCXX])
+AC_DEFUN([AX_CXX_COMPILE_STDCXX_11], [AX_CXX_COMPILE_STDCXX([11], [$1], [$2])])
diff --git a/m4/ax_cxx_compile_stdcxx_14.m4 b/m4/ax_cxx_compile_stdcxx_14.m4
new file mode 100644
index 0000000..094db0d
--- /dev/null
+++ b/m4/ax_cxx_compile_stdcxx_14.m4
@@ -0,0 +1,34 @@
+# =============================================================================
+#  https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx_14.html
+# =============================================================================
+#
+# SYNOPSIS
+#
+#   AX_CXX_COMPILE_STDCXX_14([ext|noext], [mandatory|optional])
+#
+# DESCRIPTION
+#
+#   Check for baseline language coverage in the compiler for the C++14
+#   standard; if necessary, add switches to CXX and CXXCPP to enable
+#   support.
+#
+#   This macro is a convenience alias for calling the AX_CXX_COMPILE_STDCXX
+#   macro with the version set to C++14.  The two optional arguments are
+#   forwarded literally as the second and third argument respectively.
+#   Please see the documentation for the AX_CXX_COMPILE_STDCXX macro for
+#   more information.  If you want to use this macro, you also need to
+#   download the ax_cxx_compile_stdcxx.m4 file.
+#
+# LICENSE
+#
+#   Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu>
+#
+#   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 5
+
+AX_REQUIRE_DEFINED([AX_CXX_COMPILE_STDCXX])
+AC_DEFUN([AX_CXX_COMPILE_STDCXX_14], [AX_CXX_COMPILE_STDCXX([14], [$1], [$2])])
diff --git a/m4/ax_cxx_compile_stdcxx_17.m4 b/m4/ax_cxx_compile_stdcxx_17.m4
new file mode 100644
index 0000000..a683417
--- /dev/null
+++ b/m4/ax_cxx_compile_stdcxx_17.m4
@@ -0,0 +1,35 @@
+# =============================================================================
+#  https://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx_17.html
+# =============================================================================
+#
+# SYNOPSIS
+#
+#   AX_CXX_COMPILE_STDCXX_17([ext|noext], [mandatory|optional])
+#
+# DESCRIPTION
+#
+#   Check for baseline language coverage in the compiler for the C++17
+#   standard; if necessary, add switches to CXX and CXXCPP to enable
+#   support.
+#
+#   This macro is a convenience alias for calling the AX_CXX_COMPILE_STDCXX
+#   macro with the version set to C++17.  The two optional arguments are
+#   forwarded literally as the second and third argument respectively.
+#   Please see the documentation for the AX_CXX_COMPILE_STDCXX macro for
+#   more information.  If you want to use this macro, you also need to
+#   download the ax_cxx_compile_stdcxx.m4 file.
+#
+# LICENSE
+#
+#   Copyright (c) 2015 Moritz Klammler <moritz@klammler.eu>
+#   Copyright (c) 2016 Krzesimir Nowak <qdlacz@gmail.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 2
+
+AX_REQUIRE_DEFINED([AX_CXX_COMPILE_STDCXX])
+AC_DEFUN([AX_CXX_COMPILE_STDCXX_17], [AX_CXX_COMPILE_STDCXX([17], [$1], [$2])])
diff --git a/m4/ax_file_escapes.m4 b/m4/ax_file_escapes.m4
new file mode 100644
index 0000000..a86fdc3
--- /dev/null
+++ b/m4/ax_file_escapes.m4
@@ -0,0 +1,30 @@
+# ===========================================================================
+#     https://www.gnu.org/software/autoconf-archive/ax_file_escapes.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_FILE_ESCAPES
+#
+# DESCRIPTION
+#
+#   Writes the specified data to the specified file.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Tom Howard <tomhoward@users.sf.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 8
+
+AC_DEFUN([AX_FILE_ESCAPES],[
+AX_DOLLAR="\$"
+AX_SRB="\\135"
+AX_SLB="\\133"
+AX_BS="\\\\"
+AX_DQ="\""
+])
diff --git a/m4/ax_prog_cc_for_build.m4 b/m4/ax_prog_cc_for_build.m4
new file mode 100644
index 0000000..18a4287
--- /dev/null
+++ b/m4/ax_prog_cc_for_build.m4
@@ -0,0 +1,141 @@
+# ===========================================================================
+#   https://www.gnu.org/software/autoconf-archive/ax_prog_cc_for_build.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_PROG_CC_FOR_BUILD
+#
+# DESCRIPTION
+#
+#   This macro searches for a C compiler that generates native executables,
+#   that is a C compiler that surely is not a cross-compiler. This can be
+#   useful if you have to generate source code at compile-time like for
+#   example GCC does.
+#
+#   The macro sets the CC_FOR_BUILD and CPP_FOR_BUILD macros to anything
+#   needed to compile or link (CC_FOR_BUILD) and preprocess (CPP_FOR_BUILD).
+#   The value of these variables can be overridden by the user by specifying
+#   a compiler with an environment variable (like you do for standard CC).
+#
+#   It also sets BUILD_EXEEXT and BUILD_OBJEXT to the executable and object
+#   file extensions for the build platform, and GCC_FOR_BUILD to `yes' if
+#   the compiler we found is GCC. All these variables but GCC_FOR_BUILD are
+#   substituted in the Makefile.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Paolo Bonzini <bonzini@gnu.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 18
+
+AU_ALIAS([AC_PROG_CC_FOR_BUILD], [AX_PROG_CC_FOR_BUILD])
+AC_DEFUN([AX_PROG_CC_FOR_BUILD], [dnl
+AC_REQUIRE([AC_PROG_CC])dnl
+AC_REQUIRE([AC_PROG_CPP])dnl
+AC_REQUIRE([AC_CANONICAL_BUILD])dnl
+
+dnl Use the standard macros, but make them use other variable names
+dnl
+pushdef([ac_cv_prog_CPP], ac_cv_build_prog_CPP)dnl
+pushdef([ac_cv_prog_cc_c89], ac_cv_build_prog_cc_c89)dnl
+pushdef([ac_cv_prog_gcc], ac_cv_build_prog_gcc)dnl
+pushdef([ac_cv_prog_cc_works], ac_cv_build_prog_cc_works)dnl
+pushdef([ac_cv_prog_cc_cross], ac_cv_build_prog_cc_cross)dnl
+pushdef([ac_cv_prog_cc_g], ac_cv_build_prog_cc_g)dnl
+dnl pushdef([ac_cv_c_compiler_gnu], ac_cv_build_c_compiler_gnu)dnl
+pushdef([ac_cv_exeext], ac_cv_build_exeext)dnl
+pushdef([ac_cv_objext], ac_cv_build_objext)dnl
+pushdef([ac_exeext], ac_build_exeext)dnl
+pushdef([ac_objext], ac_build_objext)dnl
+pushdef([CC], CC_FOR_BUILD)dnl
+pushdef([CPP], CPP_FOR_BUILD)dnl
+pushdef([GCC], GCC_FOR_BUILD)dnl
+pushdef([CFLAGS], CFLAGS_FOR_BUILD)dnl
+pushdef([CPPFLAGS], CPPFLAGS_FOR_BUILD)dnl
+pushdef([EXEEXT], BUILD_EXEEXT)dnl
+pushdef([LDFLAGS], LDFLAGS_FOR_BUILD)dnl
+pushdef([OBJEXT], BUILD_OBJEXT)dnl
+pushdef([host], build)dnl
+pushdef([host_alias], build_alias)dnl
+pushdef([host_cpu], build_cpu)dnl
+pushdef([host_vendor], build_vendor)dnl
+pushdef([host_os], build_os)dnl
+pushdef([ac_cv_host], ac_cv_build)dnl
+pushdef([ac_cv_host_alias], ac_cv_build_alias)dnl
+pushdef([ac_cv_host_cpu], ac_cv_build_cpu)dnl
+pushdef([ac_cv_host_vendor], ac_cv_build_vendor)dnl
+pushdef([ac_cv_host_os], ac_cv_build_os)dnl
+pushdef([ac_tool_prefix], ac_build_tool_prefix)dnl
+pushdef([am_cv_CC_dependencies_compiler_type], am_cv_build_CC_dependencies_compiler_type)dnl
+pushdef([am_cv_prog_cc_c_o], am_cv_build_prog_cc_c_o)dnl
+pushdef([cross_compiling], cross_compiling_build)dnl
+
+_save_ax_prog_cc_for_build__ac_ext="$ac_cv_c_compiler_gnu"
+cross_compiling_build=no
+
+ac_build_tool_prefix=
+AS_IF([test -n "$build"],      [ac_build_tool_prefix="$build-"],
+      [test -n "$build_alias"],[ac_build_tool_prefix="$build_alias-"])
+
+AC_LANG_PUSH([C])
+AC_PROG_CC
+_AC_COMPILER_EXEEXT
+_AC_COMPILER_OBJEXT
+AC_PROG_CPP
+
+dnl Restore the old definitions
+dnl
+ac_cv_c_compiler_gnu="$_save_ax_prog_cc_for_build__ac_ext"
+popdef([cross_compiling])dnl
+popdef([am_cv_prog_cc_c_o])dnl
+popdef([am_cv_CC_dependencies_compiler_type])dnl
+popdef([ac_tool_prefix])dnl
+popdef([ac_cv_host_os])dnl
+popdef([ac_cv_host_vendor])dnl
+popdef([ac_cv_host_cpu])dnl
+popdef([ac_cv_host_alias])dnl
+popdef([ac_cv_host])dnl
+popdef([host_os])dnl
+popdef([host_vendor])dnl
+popdef([host_cpu])dnl
+popdef([host_alias])dnl
+popdef([host])dnl
+popdef([OBJEXT])dnl
+popdef([LDFLAGS])dnl
+popdef([EXEEXT])dnl
+popdef([CPPFLAGS])dnl
+popdef([CFLAGS])dnl
+popdef([GCC])dnl
+popdef([CPP])dnl
+popdef([CC])dnl
+popdef([ac_objext])dnl
+popdef([ac_exeext])dnl
+popdef([ac_cv_objext])dnl
+popdef([ac_cv_exeext])dnl
+dnl popdef([ac_cv_c_compiler_gnu])dnl
+popdef([ac_cv_prog_cc_g])dnl
+popdef([ac_cv_prog_cc_cross])dnl
+popdef([ac_cv_prog_cc_works])dnl
+popdef([ac_cv_prog_cc_c89])dnl
+popdef([ac_cv_prog_gcc])dnl
+popdef([ac_cv_prog_CPP])dnl
+
+dnl restore global variables ac_ext, ac_cpp, ac_compile,
+dnl ac_link, ac_compiler_gnu (dependant on the current
+dnl language after popping):
+AC_LANG_POP([C])
+
+dnl Finally, set Makefile variables
+dnl
+AC_SUBST(BUILD_EXEEXT)dnl
+AC_SUBST(BUILD_OBJEXT)dnl
+AC_SUBST([CFLAGS_FOR_BUILD])dnl
+AC_SUBST([CPPFLAGS_FOR_BUILD])dnl
+AC_SUBST([LDFLAGS_FOR_BUILD])dnl
+])
diff --git a/m4/ax_pthread.m4 b/m4/ax_pthread.m4
new file mode 100644
index 0000000..1598d07
--- /dev/null
+++ b/m4/ax_pthread.m4
@@ -0,0 +1,507 @@
+# ===========================================================================
+#        https://www.gnu.org/software/autoconf-archive/ax_pthread.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
+#
+# DESCRIPTION
+#
+#   This macro figures out how to build C programs using POSIX threads. It
+#   sets the PTHREAD_LIBS output variable to the threads library and linker
+#   flags, and the PTHREAD_CFLAGS output variable to any special C compiler
+#   flags that are needed. (The user can also force certain compiler
+#   flags/libs to be tested by setting these environment variables.)
+#
+#   Also sets PTHREAD_CC to any special C compiler that is needed for
+#   multi-threaded programs (defaults to the value of CC otherwise). (This
+#   is necessary on AIX to use the special cc_r compiler alias.)
+#
+#   NOTE: You are assumed to not only compile your program with these flags,
+#   but also to link with them as well. For example, you might link with
+#   $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
+#
+#   If you are only building threaded programs, you may wish to use these
+#   variables in your default LIBS, CFLAGS, and CC:
+#
+#     LIBS="$PTHREAD_LIBS $LIBS"
+#     CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+#     CC="$PTHREAD_CC"
+#
+#   In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant
+#   has a nonstandard name, this macro defines PTHREAD_CREATE_JOINABLE to
+#   that name (e.g. PTHREAD_CREATE_UNDETACHED on AIX).
+#
+#   Also HAVE_PTHREAD_PRIO_INHERIT is defined if pthread is found and the
+#   PTHREAD_PRIO_INHERIT symbol is defined when compiling with
+#   PTHREAD_CFLAGS.
+#
+#   ACTION-IF-FOUND is a list of shell commands to run if a threads library
+#   is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
+#   is not found. If ACTION-IF-FOUND is not specified, the default action
+#   will define HAVE_PTHREAD.
+#
+#   Please let the authors know if this macro fails on any platform, or if
+#   you have any other suggestions or comments. This macro was based on work
+#   by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help
+#   from M. Frigo), as well as ac_pthread and hb_pthread macros posted by
+#   Alejandro Forero Cuervo to the autoconf macro repository. We are also
+#   grateful for the helpful feedback of numerous users.
+#
+#   Updated for Autoconf 2.68 by Daniel Richard G.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
+#   Copyright (c) 2011 Daniel Richard G. <skunk@iSKUNK.ORG>
+#   Copyright (c) 2019 Marc Stevens <marc.stevens@cwi.nl>
+#
+#   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 <https://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 27
+
+AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD])
+AC_DEFUN([AX_PTHREAD], [
+AC_REQUIRE([AC_CANONICAL_HOST])
+AC_REQUIRE([AC_PROG_CC])
+AC_REQUIRE([AC_PROG_SED])
+AC_LANG_PUSH([C])
+ax_pthread_ok=no
+
+# We used to check for pthread.h first, but this fails if pthread.h
+# requires special compiler flags (e.g. on Tru64 or Sequent).
+# It gets checked for in the link test anyway.
+
+# First of all, check if the user has set any of the PTHREAD_LIBS,
+# etcetera environment variables, and if threads linking works using
+# them:
+if test "x$PTHREAD_CFLAGS$PTHREAD_LIBS" != "x"; then
+        ax_pthread_save_CC="$CC"
+        ax_pthread_save_CFLAGS="$CFLAGS"
+        ax_pthread_save_LIBS="$LIBS"
+        AS_IF([test "x$PTHREAD_CC" != "x"], [CC="$PTHREAD_CC"])
+        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+        LIBS="$PTHREAD_LIBS $LIBS"
+        AC_MSG_CHECKING([for pthread_join using $CC $PTHREAD_CFLAGS $PTHREAD_LIBS])
+        AC_LINK_IFELSE([AC_LANG_CALL([], [pthread_join])], [ax_pthread_ok=yes])
+        AC_MSG_RESULT([$ax_pthread_ok])
+        if test "x$ax_pthread_ok" = "xno"; then
+                PTHREAD_LIBS=""
+                PTHREAD_CFLAGS=""
+        fi
+        CC="$ax_pthread_save_CC"
+        CFLAGS="$ax_pthread_save_CFLAGS"
+        LIBS="$ax_pthread_save_LIBS"
+fi
+
+# We must check for the threads library under a number of different
+# names; the ordering is very important because some systems
+# (e.g. DEC) have both -lpthread and -lpthreads, where one of the
+# libraries is broken (non-POSIX).
+
+# Create a list of thread flags to try. Items with a "," contain both
+# C compiler flags (before ",") and linker flags (after ","). Other items
+# starting with a "-" are C compiler flags, and remaining items are
+# library names, except for "none" which indicates that we try without
+# any flags at all, and "pthread-config" which is a program returning
+# the flags for the Pth emulation library.
+
+ax_pthread_flags="pthreads none -Kthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config"
+
+# The ordering *is* (sometimes) important.  Some notes on the
+# individual items follow:
+
+# pthreads: AIX (must check this before -lpthread)
+# none: in case threads are in libc; should be tried before -Kthread and
+#       other compiler flags to prevent continual compiler warnings
+# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h)
+# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads), Tru64
+#           (Note: HP C rejects this with "bad form for `-t' option")
+# -pthreads: Solaris/gcc (Note: HP C also rejects)
+# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it
+#      doesn't hurt to check since this sometimes defines pthreads and
+#      -D_REENTRANT too), HP C (must be checked before -lpthread, which
+#      is present but should not be used directly; and before -mthreads,
+#      because the compiler interprets this as "-mt" + "-hreads")
+# -mthreads: Mingw32/gcc, Lynx/gcc
+# pthread: Linux, etcetera
+# --thread-safe: KAI C++
+# pthread-config: use pthread-config program (for GNU Pth library)
+
+case $host_os in
+
+        freebsd*)
+
+        # -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
+        # lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
+
+        ax_pthread_flags="-kthread lthread $ax_pthread_flags"
+        ;;
+
+        hpux*)
+
+        # From the cc(1) man page: "[-mt] Sets various -D flags to enable
+        # multi-threading and also sets -lpthread."
+
+        ax_pthread_flags="-mt -pthread pthread $ax_pthread_flags"
+        ;;
+
+        openedition*)
+
+        # IBM z/OS requires a feature-test macro to be defined in order to
+        # enable POSIX threads at all, so give the user a hint if this is
+        # not set. (We don't define these ourselves, as they can affect
+        # other portions of the system API in unpredictable ways.)
+
+        AC_EGREP_CPP([AX_PTHREAD_ZOS_MISSING],
+            [
+#            if !defined(_OPEN_THREADS) && !defined(_UNIX03_THREADS)
+             AX_PTHREAD_ZOS_MISSING
+#            endif
+            ],
+            [AC_MSG_WARN([IBM z/OS requires -D_OPEN_THREADS or -D_UNIX03_THREADS to enable pthreads support.])])
+        ;;
+
+        solaris*)
+
+        # On Solaris (at least, for some versions), libc contains stubbed
+        # (non-functional) versions of the pthreads routines, so link-based
+        # tests will erroneously succeed. (N.B.: The stubs are missing
+        # pthread_cleanup_push, or rather a function called by this macro,
+        # so we could check for that, but who knows whether they'll stub
+        # that too in a future libc.)  So we'll check first for the
+        # standard Solaris way of linking pthreads (-mt -lpthread).
+
+        ax_pthread_flags="-mt,-lpthread pthread $ax_pthread_flags"
+        ;;
+esac
+
+# Are we compiling with Clang?
+
+AC_CACHE_CHECK([whether $CC is Clang],
+    [ax_cv_PTHREAD_CLANG],
+    [ax_cv_PTHREAD_CLANG=no
+     # Note that Autoconf sets GCC=yes for Clang as well as GCC
+     if test "x$GCC" = "xyes"; then
+        AC_EGREP_CPP([AX_PTHREAD_CC_IS_CLANG],
+            [/* Note: Clang 2.7 lacks __clang_[a-z]+__ */
+#            if defined(__clang__) && defined(__llvm__)
+             AX_PTHREAD_CC_IS_CLANG
+#            endif
+            ],
+            [ax_cv_PTHREAD_CLANG=yes])
+     fi
+    ])
+ax_pthread_clang="$ax_cv_PTHREAD_CLANG"
+
+
+# GCC generally uses -pthread, or -pthreads on some platforms (e.g. SPARC)
+
+# Note that for GCC and Clang -pthread generally implies -lpthread,
+# except when -nostdlib is passed.
+# This is problematic using libtool to build C++ shared libraries with pthread:
+# [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=25460
+# [2] https://bugzilla.redhat.com/show_bug.cgi?id=661333
+# [3] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=468555
+# To solve this, first try -pthread together with -lpthread for GCC
+
+AS_IF([test "x$GCC" = "xyes"],
+      [ax_pthread_flags="-pthread,-lpthread -pthread -pthreads $ax_pthread_flags"])
+
+# Clang takes -pthread (never supported any other flag), but we'll try with -lpthread first
+
+AS_IF([test "x$ax_pthread_clang" = "xyes"],
+      [ax_pthread_flags="-pthread,-lpthread -pthread"])
+
+
+# The presence of a feature test macro requesting re-entrant function
+# definitions is, on some systems, a strong hint that pthreads support is
+# correctly enabled
+
+case $host_os in
+        darwin* | hpux* | linux* | osf* | solaris*)
+        ax_pthread_check_macro="_REENTRANT"
+        ;;
+
+        aix*)
+        ax_pthread_check_macro="_THREAD_SAFE"
+        ;;
+
+        *)
+        ax_pthread_check_macro="--"
+        ;;
+esac
+AS_IF([test "x$ax_pthread_check_macro" = "x--"],
+      [ax_pthread_check_cond=0],
+      [ax_pthread_check_cond="!defined($ax_pthread_check_macro)"])
+
+
+if test "x$ax_pthread_ok" = "xno"; then
+for ax_pthread_try_flag in $ax_pthread_flags; do
+
+        case $ax_pthread_try_flag in
+                none)
+                AC_MSG_CHECKING([whether pthreads work without any flags])
+                ;;
+
+                *,*)
+                PTHREAD_CFLAGS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\1/"`
+                PTHREAD_LIBS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\2/"`
+                AC_MSG_CHECKING([whether pthreads work with "$PTHREAD_CFLAGS" and "$PTHREAD_LIBS"])
+                ;;
+
+                -*)
+                AC_MSG_CHECKING([whether pthreads work with $ax_pthread_try_flag])
+                PTHREAD_CFLAGS="$ax_pthread_try_flag"
+                ;;
+
+                pthread-config)
+                AC_CHECK_PROG([ax_pthread_config], [pthread-config], [yes], [no])
+                AS_IF([test "x$ax_pthread_config" = "xno"], [continue])
+                PTHREAD_CFLAGS="`pthread-config --cflags`"
+                PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`"
+                ;;
+
+                *)
+                AC_MSG_CHECKING([for the pthreads library -l$ax_pthread_try_flag])
+                PTHREAD_LIBS="-l$ax_pthread_try_flag"
+                ;;
+        esac
+
+        ax_pthread_save_CFLAGS="$CFLAGS"
+        ax_pthread_save_LIBS="$LIBS"
+        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+        LIBS="$PTHREAD_LIBS $LIBS"
+
+        # Check for various functions.  We must include pthread.h,
+        # since some functions may be macros.  (On the Sequent, we
+        # need a special flag -Kthread to make this header compile.)
+        # We check for pthread_join because it is in -lpthread on IRIX
+        # while pthread_create is in libc.  We check for pthread_attr_init
+        # due to DEC craziness with -lpthreads.  We check for
+        # pthread_cleanup_push because it is one of the few pthread
+        # functions on Solaris that doesn't have a non-functional libc stub.
+        # We try pthread_create on general principles.
+
+        AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>
+#                       if $ax_pthread_check_cond
+#                        error "$ax_pthread_check_macro must be defined"
+#                       endif
+                        static void *some_global = NULL;
+                        static void routine(void *a)
+                          {
+                             /* To avoid any unused-parameter or
+                                unused-but-set-parameter warning.  */
+                             some_global = a;
+                          }
+                        static void *start_routine(void *a) { return a; }],
+                       [pthread_t th; pthread_attr_t attr;
+                        pthread_create(&th, 0, start_routine, 0);
+                        pthread_join(th, 0);
+                        pthread_attr_init(&attr);
+                        pthread_cleanup_push(routine, 0);
+                        pthread_cleanup_pop(0) /* ; */])],
+            [ax_pthread_ok=yes],
+            [])
+
+        CFLAGS="$ax_pthread_save_CFLAGS"
+        LIBS="$ax_pthread_save_LIBS"
+
+        AC_MSG_RESULT([$ax_pthread_ok])
+        AS_IF([test "x$ax_pthread_ok" = "xyes"], [break])
+
+        PTHREAD_LIBS=""
+        PTHREAD_CFLAGS=""
+done
+fi
+
+
+# Clang needs special handling, because older versions handle the -pthread
+# option in a rather... idiosyncratic way
+
+if test "x$ax_pthread_clang" = "xyes"; then
+
+        # Clang takes -pthread; it has never supported any other flag
+
+        # (Note 1: This will need to be revisited if a system that Clang
+        # supports has POSIX threads in a separate library.  This tends not
+        # to be the way of modern systems, but it's conceivable.)
+
+        # (Note 2: On some systems, notably Darwin, -pthread is not needed
+        # to get POSIX threads support; the API is always present and
+        # active.  We could reasonably leave PTHREAD_CFLAGS empty.  But
+        # -pthread does define _REENTRANT, and while the Darwin headers
+        # ignore this macro, third-party headers might not.)
+
+        # However, older versions of Clang make a point of warning the user
+        # that, in an invocation where only linking and no compilation is
+        # taking place, the -pthread option has no effect ("argument unused
+        # during compilation").  They expect -pthread to be passed in only
+        # when source code is being compiled.
+        #
+        # Problem is, this is at odds with the way Automake and most other
+        # C build frameworks function, which is that the same flags used in
+        # compilation (CFLAGS) are also used in linking.  Many systems
+        # supported by AX_PTHREAD require exactly this for POSIX threads
+        # support, and in fact it is often not straightforward to specify a
+        # flag that is used only in the compilation phase and not in
+        # linking.  Such a scenario is extremely rare in practice.
+        #
+        # Even though use of the -pthread flag in linking would only print
+        # a warning, this can be a nuisance for well-run software projects
+        # that build with -Werror.  So if the active version of Clang has
+        # this misfeature, we search for an option to squash it.
+
+        AC_CACHE_CHECK([whether Clang needs flag to prevent "argument unused" warning when linking with -pthread],
+            [ax_cv_PTHREAD_CLANG_NO_WARN_FLAG],
+            [ax_cv_PTHREAD_CLANG_NO_WARN_FLAG=unknown
+             # Create an alternate version of $ac_link that compiles and
+             # links in two steps (.c -> .o, .o -> exe) instead of one
+             # (.c -> exe), because the warning occurs only in the second
+             # step
+             ax_pthread_save_ac_link="$ac_link"
+             ax_pthread_sed='s/conftest\.\$ac_ext/conftest.$ac_objext/g'
+             ax_pthread_link_step=`$as_echo "$ac_link" | sed "$ax_pthread_sed"`
+             ax_pthread_2step_ac_link="($ac_compile) && (echo ==== >&5) && ($ax_pthread_link_step)"
+             ax_pthread_save_CFLAGS="$CFLAGS"
+             for ax_pthread_try in '' -Qunused-arguments -Wno-unused-command-line-argument unknown; do
+                AS_IF([test "x$ax_pthread_try" = "xunknown"], [break])
+                CFLAGS="-Werror -Wunknown-warning-option $ax_pthread_try -pthread $ax_pthread_save_CFLAGS"
+                ac_link="$ax_pthread_save_ac_link"
+                AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])],
+                    [ac_link="$ax_pthread_2step_ac_link"
+                     AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])],
+                         [break])
+                    ])
+             done
+             ac_link="$ax_pthread_save_ac_link"
+             CFLAGS="$ax_pthread_save_CFLAGS"
+             AS_IF([test "x$ax_pthread_try" = "x"], [ax_pthread_try=no])
+             ax_cv_PTHREAD_CLANG_NO_WARN_FLAG="$ax_pthread_try"
+            ])
+
+        case "$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG" in
+                no | unknown) ;;
+                *) PTHREAD_CFLAGS="$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG $PTHREAD_CFLAGS" ;;
+        esac
+
+fi # $ax_pthread_clang = yes
+
+
+
+# Various other checks:
+if test "x$ax_pthread_ok" = "xyes"; then
+        ax_pthread_save_CFLAGS="$CFLAGS"
+        ax_pthread_save_LIBS="$LIBS"
+        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+        LIBS="$PTHREAD_LIBS $LIBS"
+
+        # Detect AIX lossage: JOINABLE attribute is called UNDETACHED.
+        AC_CACHE_CHECK([for joinable pthread attribute],
+            [ax_cv_PTHREAD_JOINABLE_ATTR],
+            [ax_cv_PTHREAD_JOINABLE_ATTR=unknown
+             for ax_pthread_attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do
+                 AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>],
+                                                 [int attr = $ax_pthread_attr; return attr /* ; */])],
+                                [ax_cv_PTHREAD_JOINABLE_ATTR=$ax_pthread_attr; break],
+                                [])
+             done
+            ])
+        AS_IF([test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xunknown" && \
+               test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xPTHREAD_CREATE_JOINABLE" && \
+               test "x$ax_pthread_joinable_attr_defined" != "xyes"],
+              [AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE],
+                                  [$ax_cv_PTHREAD_JOINABLE_ATTR],
+                                  [Define to necessary symbol if this constant
+                                   uses a non-standard name on your system.])
+               ax_pthread_joinable_attr_defined=yes
+              ])
+
+        AC_CACHE_CHECK([whether more special flags are required for pthreads],
+            [ax_cv_PTHREAD_SPECIAL_FLAGS],
+            [ax_cv_PTHREAD_SPECIAL_FLAGS=no
+             case $host_os in
+             solaris*)
+             ax_cv_PTHREAD_SPECIAL_FLAGS="-D_POSIX_PTHREAD_SEMANTICS"
+             ;;
+             esac
+            ])
+        AS_IF([test "x$ax_cv_PTHREAD_SPECIAL_FLAGS" != "xno" && \
+               test "x$ax_pthread_special_flags_added" != "xyes"],
+              [PTHREAD_CFLAGS="$ax_cv_PTHREAD_SPECIAL_FLAGS $PTHREAD_CFLAGS"
+               ax_pthread_special_flags_added=yes])
+
+        AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT],
+            [ax_cv_PTHREAD_PRIO_INHERIT],
+            [AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
+                                             [[int i = PTHREAD_PRIO_INHERIT;
+                                               return i;]])],
+                            [ax_cv_PTHREAD_PRIO_INHERIT=yes],
+                            [ax_cv_PTHREAD_PRIO_INHERIT=no])
+            ])
+        AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes" && \
+               test "x$ax_pthread_prio_inherit_defined" != "xyes"],
+              [AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have PTHREAD_PRIO_INHERIT.])
+               ax_pthread_prio_inherit_defined=yes
+              ])
+
+        CFLAGS="$ax_pthread_save_CFLAGS"
+        LIBS="$ax_pthread_save_LIBS"
+
+        # More AIX lossage: compile with *_r variant
+        if test "x$GCC" != "xyes"; then
+            case $host_os in
+                aix*)
+                AS_CASE(["x/$CC"],
+                    [x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6],
+                    [#handle absolute path differently from PATH based program lookup
+                     AS_CASE(["x$CC"],
+                         [x/*],
+                         [AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"])],
+                         [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])])
+                ;;
+            esac
+        fi
+fi
+
+test -n "$PTHREAD_CC" || PTHREAD_CC="$CC"
+
+AC_SUBST([PTHREAD_LIBS])
+AC_SUBST([PTHREAD_CFLAGS])
+AC_SUBST([PTHREAD_CC])
+
+# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
+if test "x$ax_pthread_ok" = "xyes"; then
+        ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])
+        :
+else
+        ax_pthread_ok=no
+        $2
+fi
+AC_LANG_POP
+])dnl AX_PTHREAD
diff --git a/m4/ax_with_curses.m4 b/m4/ax_with_curses.m4
new file mode 100644
index 0000000..cf1ee01
--- /dev/null
+++ b/m4/ax_with_curses.m4
@@ -0,0 +1,517 @@
+# ===========================================================================
+#      http://www.gnu.org/software/autoconf-archive/ax_with_curses.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_WITH_CURSES
+#
+# DESCRIPTION
+#
+#   This macro checks whether a SysV or X/Open-compatible Curses library is
+#   present, along with the associated header file.  The NcursesW
+#   (wide-character) library is searched for first, followed by Ncurses,
+#   then the system-default plain Curses.  The first library found is the
+#   one returned.
+#
+#   The following options are understood: --with-ncursesw, --with-ncurses,
+#   --without-ncursesw, --without-ncurses.  The "--with" options force the
+#   macro to use that particular library, terminating with an error if not
+#   found.  The "--without" options simply skip the check for that library.
+#   The effect on the search pattern is:
+#
+#     (no options)                           - NcursesW, Ncurses, Curses
+#     --with-ncurses     --with-ncursesw     - NcursesW only [*]
+#     --without-ncurses  --with-ncursesw     - NcursesW only [*]
+#                        --with-ncursesw     - NcursesW only [*]
+#     --with-ncurses     --without-ncursesw  - Ncurses only [*]
+#     --with-ncurses                         - NcursesW, Ncurses [**]
+#     --without-ncurses  --without-ncursesw  - Curses only
+#                        --without-ncursesw  - Ncurses, Curses
+#     --without-ncurses                      - NcursesW, Curses
+#
+#   [*]  If the library is not found, abort the configure script.
+#
+#   [**] If the second library (Ncurses) is not found, abort configure.
+#
+#   The following preprocessor symbols may be defined by this macro if the
+#   appropriate conditions are met:
+#
+#     HAVE_CURSES             - if any SysV or X/Open Curses library found
+#     HAVE_CURSES_ENHANCED    - if library supports X/Open Enhanced functions
+#     HAVE_CURSES_COLOR       - if library supports color (enhanced functions)
+#     HAVE_CURSES_OBSOLETE    - if library supports certain obsolete features
+#     HAVE_NCURSESW           - if NcursesW (wide char) library is to be used
+#     HAVE_NCURSES            - if the Ncurses library is to be used
+#
+#     HAVE_CURSES_H           - if <curses.h> is present and should be used
+#     HAVE_NCURSESW_H         - if <ncursesw.h> should be used
+#     HAVE_NCURSES_H          - if <ncurses.h> should be used
+#     HAVE_NCURSESW_CURSES_H  - if <ncursesw/curses.h> should be used
+#     HAVE_NCURSES_CURSES_H   - if <ncurses/curses.h> should be used
+#
+#   (These preprocessor symbols are discussed later in this document.)
+#
+#   The following output variable is defined by this macro; it is precious
+#   and may be overridden on the ./configure command line:
+#
+#     CURSES_LIB  - library to add to xxx_LDADD
+#
+#   The library listed in CURSES_LIB is NOT added to LIBS by default. You
+#   need to add CURSES_LIB to the appropriate xxx_LDADD line in your
+#   Makefile.am.  For example:
+#
+#     prog_LDADD = @CURSES_LIB@
+#
+#   If CURSES_LIB is set on the configure command line (such as by running
+#   "./configure CURSES_LIB=-lmycurses"), then the only header searched for
+#   is <curses.h>.  The user may use the CPPFLAGS precious variable to
+#   override the standard #include search path.  If the user needs to
+#   specify an alternative path for a library (such as for a non-standard
+#   NcurseW), the user should use the LDFLAGS variable.
+#
+#   The following shell variables may be defined by this macro:
+#
+#     ax_cv_curses           - set to "yes" if any Curses library found
+#     ax_cv_curses_enhanced  - set to "yes" if Enhanced functions present
+#     ax_cv_curses_color     - set to "yes" if color functions present
+#     ax_cv_curses_obsolete  - set to "yes" if obsolete features present
+#
+#     ax_cv_ncursesw      - set to "yes" if NcursesW library found
+#     ax_cv_ncurses       - set to "yes" if Ncurses library found
+#     ax_cv_plaincurses   - set to "yes" if plain Curses library found
+#     ax_cv_curses_which  - set to "ncursesw", "ncurses", "plaincurses" or "no"
+#
+#   These variables can be used in your configure.ac to determine the level
+#   of support you need from the Curses library.  For example, if you must
+#   have either Ncurses or NcursesW, you could include:
+#
+#     AX_WITH_CURSES
+#     if test "x$ax_cv_ncursesw" != xyes && test "x$ax_cv_ncurses" != xyes; then
+#         AX_MSG_ERROR([requires either NcursesW or Ncurses library])
+#     fi
+#
+#   If any Curses library will do (but one must be present and must support
+#   color), you could use:
+#
+#     AX_WITH_CURSES
+#     if test "x$ax_cv_curses" != xyes || test "x$ax_cv_curses_color" != xyes; then
+#         AC_MSG_ERROR([requires an X/Open-compatible Curses library with color])
+#     fi
+#
+#   Certain preprocessor symbols and shell variables defined by this macro
+#   can be used to determine various features of the Curses library.  In
+#   particular, HAVE_CURSES and ax_cv_curses are defined if the Curses
+#   library found conforms to the traditional SysV and/or X/Open Base Curses
+#   definition.  Any working Curses library conforms to this level.
+#
+#   HAVE_CURSES_ENHANCED and ax_cv_curses_enhanced are defined if the
+#   library supports the X/Open Enhanced Curses definition.  In particular,
+#   the wide-character types attr_t, cchar_t and wint_t, the functions
+#   wattr_set() and wget_wch() and the macros WA_NORMAL and _XOPEN_CURSES
+#   are checked.  The Ncurses library does NOT conform to this definition,
+#   although NcursesW does.
+#
+#   HAVE_CURSES_COLOR and ax_cv_curses_color are defined if the library
+#   supports color functions and macros such as COLOR_PAIR, A_COLOR,
+#   COLOR_WHITE, COLOR_RED and init_pair().  These are NOT part of the
+#   X/Open Base Curses definition, but are part of the Enhanced set of
+#   functions.  The Ncurses library DOES support these functions, as does
+#   NcursesW.
+#
+#   HAVE_CURSES_OBSOLETE and ax_cv_curses_obsolete are defined if the
+#   library supports certain features present in SysV and BSD Curses but not
+#   defined in the X/Open definition.  In particular, the functions
+#   getattrs(), getcurx() and getmaxx() are checked.
+#
+#   To use the HAVE_xxx_H preprocessor symbols, insert the following into
+#   your system.h (or equivalent) header file:
+#
+#     #if defined HAVE_NCURSESW_CURSES_H
+#     #  include <ncursesw/curses.h>
+#     #elif defined HAVE_NCURSESW_H
+#     #  include <ncursesw.h>
+#     #elif defined HAVE_NCURSES_CURSES_H
+#     #  include <ncurses/curses.h>
+#     #elif defined HAVE_NCURSES_H
+#     #  include <ncurses.h>
+#     #elif defined HAVE_CURSES_H
+#     #  include <curses.h>
+#     #else
+#     #  error "SysV or X/Open-compatible Curses header file required"
+#     #endif
+#
+#   For previous users of this macro: you should not need to change anything
+#   in your configure.ac or Makefile.am, as the previous (serial 10)
+#   semantics are still valid.  However, you should update your system.h (or
+#   equivalent) header file to the fragment shown above. You are encouraged
+#   also to make use of the extended functionality provided by this version
+#   of AX_WITH_CURSES, as well as in the additional macros
+#   AX_WITH_CURSES_PANEL, AX_WITH_CURSES_MENU and AX_WITH_CURSES_FORM.
+#
+# LICENSE
+#
+#   Copyright (c) 2009 Mark Pulford <mark@kyne.com.au>
+#   Copyright (c) 2009 Damian Pietras <daper@daper.net>
+#   Copyright (c) 2012 Reuben Thomas <rrt@sc3d.org>
+#   Copyright (c) 2011 John Zaitseff <J.Zaitseff@zap.org.au>
+#
+#   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 13
+
+AC_DEFUN([AX_WITH_CURSES], [
+    AC_ARG_VAR([CURSES_LIB], [linker library for Curses, e.g. -lcurses])
+    AC_ARG_WITH([ncurses], [AS_HELP_STRING([--with-ncurses],
+        [force the use of Ncurses or NcursesW])],
+        [], [with_ncurses=check])
+    AC_ARG_WITH([ncursesw], [AS_HELP_STRING([--without-ncursesw],
+        [do not use NcursesW (wide character support)])],
+        [], [with_ncursesw=check])
+
+    ax_saved_LIBS=$LIBS
+    AS_IF([test "x$with_ncurses" = xyes || test "x$with_ncursesw" = xyes],
+        [ax_with_plaincurses=no], [ax_with_plaincurses=check])
+
+    ax_cv_curses_which=no
+
+    # Test for NcursesW
+
+    AS_IF([test "x$CURSES_LIB" = x && test "x$with_ncursesw" != xno], [
+        LIBS="$ax_saved_LIBS -lncursesw"
+
+        AC_CACHE_CHECK([for NcursesW wide-character library], [ax_cv_ncursesw], [
+            AC_LINK_IFELSE([AC_LANG_CALL([], [initscr])],
+                [ax_cv_ncursesw=yes], [ax_cv_ncursesw=no])
+        ])
+        AS_IF([test "x$ax_cv_ncursesw" = xno && test "x$with_ncursesw" = xyes], [
+            AC_MSG_ERROR([--with-ncursesw specified but could not find NcursesW library])
+        ])
+
+        AS_IF([test "x$ax_cv_ncursesw" = xyes], [
+            ax_cv_curses=yes
+            ax_cv_curses_which=ncursesw
+            CURSES_LIB="-lncursesw"
+            AC_DEFINE([HAVE_NCURSESW], [1], [Define to 1 if the NcursesW library is present])
+            AC_DEFINE([HAVE_CURSES],   [1], [Define to 1 if a SysV or X/Open compatible Curses library is present])
+
+            AC_CACHE_CHECK([for working ncursesw/curses.h], [ax_cv_header_ncursesw_curses_h], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@define _XOPEN_SOURCE_EXTENDED 1
+                        @%:@include <ncursesw/curses.h>
+                    ]], [[
+                        chtype a = A_BOLD;
+                        int b = KEY_LEFT;
+                        chtype c = COLOR_PAIR(1) & A_COLOR;
+                        attr_t d = WA_NORMAL;
+                        cchar_t e;
+                        wint_t f;
+                        int g = getattrs(stdscr);
+                        int h = getcurx(stdscr) + getmaxx(stdscr);
+                        initscr();
+                        init_pair(1, COLOR_WHITE, COLOR_RED);
+                        wattr_set(stdscr, d, 0, NULL);
+                        wget_wch(stdscr, &f);
+                    ]])],
+                    [ax_cv_header_ncursesw_curses_h=yes],
+                    [ax_cv_header_ncursesw_curses_h=no])
+            ])
+            AS_IF([test "x$ax_cv_header_ncursesw_curses_h" = xyes], [
+                ax_cv_curses_enhanced=yes
+                ax_cv_curses_color=yes
+                ax_cv_curses_obsolete=yes
+                AC_DEFINE([HAVE_CURSES_ENHANCED],   [1], [Define to 1 if library supports X/Open Enhanced functions])
+                AC_DEFINE([HAVE_CURSES_COLOR],      [1], [Define to 1 if library supports color (enhanced functions)])
+                AC_DEFINE([HAVE_CURSES_OBSOLETE],   [1], [Define to 1 if library supports certain obsolete features])
+                AC_DEFINE([HAVE_NCURSESW_CURSES_H], [1], [Define to 1 if <ncursesw/curses.h> is present])
+            ])
+
+            AC_CACHE_CHECK([for working ncursesw.h], [ax_cv_header_ncursesw_h], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@define _XOPEN_SOURCE_EXTENDED 1
+                        @%:@include <ncursesw.h>
+                    ]], [[
+                        chtype a = A_BOLD;
+                        int b = KEY_LEFT;
+                        chtype c = COLOR_PAIR(1) & A_COLOR;
+                        attr_t d = WA_NORMAL;
+                        cchar_t e;
+                        wint_t f;
+                        int g = getattrs(stdscr);
+                        int h = getcurx(stdscr) + getmaxx(stdscr);
+                        initscr();
+                        init_pair(1, COLOR_WHITE, COLOR_RED);
+                        wattr_set(stdscr, d, 0, NULL);
+                        wget_wch(stdscr, &f);
+                    ]])],
+                    [ax_cv_header_ncursesw_h=yes],
+                    [ax_cv_header_ncursesw_h=no])
+            ])
+            AS_IF([test "x$ax_cv_header_ncursesw_h" = xyes], [
+                ax_cv_curses_enhanced=yes
+                ax_cv_curses_color=yes
+                ax_cv_curses_obsolete=yes
+                AC_DEFINE([HAVE_CURSES_ENHANCED], [1], [Define to 1 if library supports X/Open Enhanced functions])
+                AC_DEFINE([HAVE_CURSES_COLOR],    [1], [Define to 1 if library supports color (enhanced functions)])
+                AC_DEFINE([HAVE_CURSES_OBSOLETE], [1], [Define to 1 if library supports certain obsolete features])
+                AC_DEFINE([HAVE_NCURSESW_H],      [1], [Define to 1 if <ncursesw.h> is present])
+            ])
+
+            AC_CACHE_CHECK([for working ncurses.h], [ax_cv_header_ncurses_h_with_ncursesw], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@define _XOPEN_SOURCE_EXTENDED 1
+                        @%:@include <ncurses.h>
+                    ]], [[
+                        chtype a = A_BOLD;
+                        int b = KEY_LEFT;
+                        chtype c = COLOR_PAIR(1) & A_COLOR;
+                        attr_t d = WA_NORMAL;
+                        cchar_t e;
+                        wint_t f;
+                        int g = getattrs(stdscr);
+                        int h = getcurx(stdscr) + getmaxx(stdscr);
+                        initscr();
+                        init_pair(1, COLOR_WHITE, COLOR_RED);
+                        wattr_set(stdscr, d, 0, NULL);
+                        wget_wch(stdscr, &f);
+                    ]])],
+                    [ax_cv_header_ncurses_h_with_ncursesw=yes],
+                    [ax_cv_header_ncurses_h_with_ncursesw=no])
+            ])
+            AS_IF([test "x$ax_cv_header_ncurses_h_with_ncursesw" = xyes], [
+                ax_cv_curses_enhanced=yes
+                ax_cv_curses_color=yes
+                ax_cv_curses_obsolete=yes
+                AC_DEFINE([HAVE_CURSES_ENHANCED], [1], [Define to 1 if library supports X/Open Enhanced functions])
+                AC_DEFINE([HAVE_CURSES_COLOR],    [1], [Define to 1 if library supports color (enhanced functions)])
+                AC_DEFINE([HAVE_CURSES_OBSOLETE], [1], [Define to 1 if library supports certain obsolete features])
+                AC_DEFINE([HAVE_NCURSES_H],       [1], [Define to 1 if <ncurses.h> is present])
+            ])
+
+            AS_IF([test "x$ax_cv_header_ncursesw_curses_h" = xno && test "x$ax_cv_header_ncursesw_h" = xno && test "x$ax_cv_header_ncurses_h_with_ncursesw" = xno], [
+                AC_MSG_WARN([could not find a working ncursesw/curses.h, ncursesw.h or ncurses.h])
+            ])
+        ])
+    ])
+
+    # Test for Ncurses
+
+    AS_IF([test "x$CURSES_LIB" = x && test "x$with_ncurses" != xno && test "x$ax_cv_curses_which" = xno], [
+        LIBS="$ax_saved_LIBS -lncurses"
+
+        AC_CACHE_CHECK([for Ncurses library], [ax_cv_ncurses], [
+            AC_LINK_IFELSE([AC_LANG_CALL([], [initscr])],
+                [ax_cv_ncurses=yes], [ax_cv_ncurses=no])
+        ])
+        AS_IF([test "x$ax_cv_ncurses" = xno && test "x$with_ncurses" = xyes], [
+            AC_MSG_ERROR([--with-ncurses specified but could not find Ncurses library])
+        ])
+
+        AS_IF([test "x$ax_cv_ncurses" = xyes], [
+            ax_cv_curses=yes
+            ax_cv_curses_which=ncurses
+            CURSES_LIB="-lncurses"
+            AC_DEFINE([HAVE_NCURSES], [1], [Define to 1 if the Ncurses library is present])
+            AC_DEFINE([HAVE_CURSES],  [1], [Define to 1 if a SysV or X/Open compatible Curses library is present])
+
+            AC_CACHE_CHECK([for working ncurses/curses.h], [ax_cv_header_ncurses_curses_h], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@include <ncurses/curses.h>
+                    ]], [[
+                        chtype a = A_BOLD;
+                        int b = KEY_LEFT;
+                        chtype c = COLOR_PAIR(1) & A_COLOR;
+                        int g = getattrs(stdscr);
+                        int h = getcurx(stdscr) + getmaxx(stdscr);
+                        initscr();
+                        init_pair(1, COLOR_WHITE, COLOR_RED);
+                    ]])],
+                    [ax_cv_header_ncurses_curses_h=yes],
+                    [ax_cv_header_ncurses_curses_h=no])
+            ])
+            AS_IF([test "x$ax_cv_header_ncurses_curses_h" = xyes], [
+                ax_cv_curses_color=yes
+                ax_cv_curses_obsolete=yes
+                AC_DEFINE([HAVE_CURSES_COLOR],     [1], [Define to 1 if library supports color (enhanced functions)])
+                AC_DEFINE([HAVE_CURSES_OBSOLETE],  [1], [Define to 1 if library supports certain obsolete features])
+                AC_DEFINE([HAVE_NCURSES_CURSES_H], [1], [Define to 1 if <ncurses/curses.h> is present])
+            ])
+
+            AC_CACHE_CHECK([for working ncurses.h], [ax_cv_header_ncurses_h], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@include <ncurses.h>
+                    ]], [[
+                        chtype a = A_BOLD;
+                        int b = KEY_LEFT;
+                        chtype c = COLOR_PAIR(1) & A_COLOR;
+                        int g = getattrs(stdscr);
+                        int h = getcurx(stdscr) + getmaxx(stdscr);
+                        initscr();
+                        init_pair(1, COLOR_WHITE, COLOR_RED);
+                    ]])],
+                    [ax_cv_header_ncurses_h=yes],
+                    [ax_cv_header_ncurses_h=no])
+            ])
+            AS_IF([test "x$ax_cv_header_ncurses_h" = xyes], [
+                ax_cv_curses_color=yes
+                ax_cv_curses_obsolete=yes
+                AC_DEFINE([HAVE_CURSES_COLOR],    [1], [Define to 1 if library supports color (enhanced functions)])
+                AC_DEFINE([HAVE_CURSES_OBSOLETE], [1], [Define to 1 if library supports certain obsolete features])
+                AC_DEFINE([HAVE_NCURSES_H],       [1], [Define to 1 if <ncurses.h> is present])
+            ])
+
+            AS_IF([test "x$ax_cv_header_ncurses_curses_h" = xno && test "x$ax_cv_header_ncurses_h" = xno], [
+                AC_MSG_WARN([could not find a working ncurses/curses.h or ncurses.h])
+            ])
+        ])
+    ])
+
+    # Test for plain Curses (or if CURSES_LIB was set by user)
+
+    AS_IF([test "x$with_plaincurses" != xno && test "x$ax_cv_curses_which" = xno], [
+        AS_IF([test "x$CURSES_LIB" != x], [
+            LIBS="$ax_saved_LIBS $CURSES_LIB"
+        ], [
+            LIBS="$ax_saved_LIBS -lcurses"
+        ])
+
+        AC_CACHE_CHECK([for Curses library], [ax_cv_plaincurses], [
+            AC_LINK_IFELSE([AC_LANG_CALL([], [initscr])],
+                [ax_cv_plaincurses=yes], [ax_cv_plaincurses=no])
+        ])
+
+        AS_IF([test "x$ax_cv_plaincurses" = xyes], [
+            ax_cv_curses=yes
+            ax_cv_curses_which=plaincurses
+            AS_IF([test "x$CURSES_LIB" = x], [
+                CURSES_LIB="-lcurses"
+            ])
+            AC_DEFINE([HAVE_CURSES], [1], [Define to 1 if a SysV or X/Open compatible Curses library is present])
+
+            # Check for base conformance (and header file)
+
+            AC_CACHE_CHECK([for working curses.h], [ax_cv_header_curses_h], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@include <curses.h>
+                    ]], [[
+                        chtype a = A_BOLD;
+                        int b = KEY_LEFT;
+                        initscr();
+                    ]])],
+                    [ax_cv_header_curses_h=yes],
+                    [ax_cv_header_curses_h=no])
+            ])
+            AS_IF([test "x$ax_cv_header_curses_h" = xyes], [
+                AC_DEFINE([HAVE_CURSES_H], [1], [Define to 1 if <curses.h> is present])
+
+                # Check for X/Open Enhanced conformance
+
+                AC_CACHE_CHECK([for X/Open Enhanced Curses conformance], [ax_cv_plaincurses_enhanced], [
+                    AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                            @%:@define _XOPEN_SOURCE_EXTENDED 1
+                            @%:@include <curses.h>
+                            @%:@ifndef _XOPEN_CURSES
+                            @%:@error "this Curses library is not enhanced"
+                            "this Curses library is not enhanced"
+                            @%:@endif
+                        ]], [[
+                            chtype a = A_BOLD;
+                            int b = KEY_LEFT;
+                            chtype c = COLOR_PAIR(1) & A_COLOR;
+                            attr_t d = WA_NORMAL;
+                            cchar_t e;
+                            wint_t f;
+                            initscr();
+                            init_pair(1, COLOR_WHITE, COLOR_RED);
+                            wattr_set(stdscr, d, 0, NULL);
+                            wget_wch(stdscr, &f);
+                        ]])],
+                        [ax_cv_plaincurses_enhanced=yes],
+                        [ax_cv_plaincurses_enhanced=no])
+                ])
+                AS_IF([test "x$ax_cv_plaincurses_enhanced" = xyes], [
+                    ax_cv_curses_enhanced=yes
+                    ax_cv_curses_color=yes
+                    AC_DEFINE([HAVE_CURSES_ENHANCED], [1], [Define to 1 if library supports X/Open Enhanced functions])
+                    AC_DEFINE([HAVE_CURSES_COLOR],    [1], [Define to 1 if library supports color (enhanced functions)])
+                ])
+
+                # Check for color functions
+
+                AC_CACHE_CHECK([for Curses color functions], [ax_cv_plaincurses_color], [
+                    AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@define _XOPEN_SOURCE_EXTENDED 1
+                        @%:@include <curses.h>
+                        ]], [[
+                            chtype a = A_BOLD;
+                            int b = KEY_LEFT;
+                            chtype c = COLOR_PAIR(1) & A_COLOR;
+                            initscr();
+                            init_pair(1, COLOR_WHITE, COLOR_RED);
+                        ]])],
+                        [ax_cv_plaincurses_color=yes],
+                        [ax_cv_plaincurses_color=no])
+                ])
+                AS_IF([test "x$ax_cv_plaincurses_color" = xyes], [
+                    ax_cv_curses_color=yes
+                    AC_DEFINE([HAVE_CURSES_COLOR], [1], [Define to 1 if library supports color (enhanced functions)])
+                ])
+
+                # Check for obsolete functions
+
+                AC_CACHE_CHECK([for obsolete Curses functions], [ax_cv_plaincurses_obsolete], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[
+                        @%:@include <curses.h>
+                    ]], [[
+                        chtype a = A_BOLD;
+                        int b = KEY_LEFT;
+                        int g = getattrs(stdscr);
+                        int h = getcurx(stdscr) + getmaxx(stdscr);
+                        initscr();
+                    ]])],
+                    [ax_cv_plaincurses_obsolete=yes],
+                    [ax_cv_plaincurses_obsolete=no])
+                ])
+                AS_IF([test "x$ax_cv_plaincurses_obsolete" = xyes], [
+                    ax_cv_curses_obsolete=yes
+                    AC_DEFINE([HAVE_CURSES_OBSOLETE], [1], [Define to 1 if library supports certain obsolete features])
+                ])
+            ])
+
+            AS_IF([test "x$ax_cv_header_curses_h" = xno], [
+                AC_MSG_WARN([could not find a working curses.h])
+            ])
+        ])
+    ])
+
+    AS_IF([test "x$ax_cv_curses"          != xyes], [ax_cv_curses=no])
+    AS_IF([test "x$ax_cv_curses_enhanced" != xyes], [ax_cv_curses_enhanced=no])
+    AS_IF([test "x$ax_cv_curses_color"    != xyes], [ax_cv_curses_color=no])
+    AS_IF([test "x$ax_cv_curses_obsolete" != xyes], [ax_cv_curses_obsolete=no])
+
+    LIBS=$ax_saved_LIBS
+])dnl
diff --git a/m4/libcurl.m4 b/m4/libcurl.m4
new file mode 100644
index 0000000..02d00a7
--- /dev/null
+++ b/m4/libcurl.m4
@@ -0,0 +1,301 @@
+#***************************************************************************
+#                                  _   _ ____  _
+#  Project                     ___| | | |  _ \| |
+#                             / __| | | | |_) | |
+#                            | (__| |_| |  _ <| |___
+#                             \___|\___/|_| \_\_____|
+#
+# Copyright (C) 2006 - 2020, David Shaw <dshaw@jabberwocky.com>
+#
+# This software is licensed as described in the file COPYING, which
+# you should have received as part of this distribution. The terms
+# are also available at https://curl.se/docs/copyright.html.
+#
+# You may opt to use, copy, modify, merge, publish, distribute and/or sell
+# copies of the Software, and permit persons to whom the Software is
+# furnished to do so, under the terms of the COPYING file.
+#
+# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+# KIND, either express or implied.
+#
+###########################################################################
+# LIBCURL_CHECK_CONFIG ([DEFAULT-ACTION], [MINIMUM-VERSION],
+#                       [ACTION-IF-YES], [ACTION-IF-NO])
+# ----------------------------------------------------------
+#      David Shaw <dshaw@jabberwocky.com>   May-09-2006
+#
+# Checks for libcurl.  DEFAULT-ACTION is the string yes or no to
+# specify whether to default to --with-libcurl or --without-libcurl.
+# If not supplied, DEFAULT-ACTION is yes.  MINIMUM-VERSION is the
+# minimum version of libcurl to accept.  Pass the version as a regular
+# version number like 7.10.1. If not supplied, any version is
+# accepted.  ACTION-IF-YES is a list of shell commands to run if
+# libcurl was successfully found and passed the various tests.
+# ACTION-IF-NO is a list of shell commands that are run otherwise.
+# Note that using --without-libcurl does run ACTION-IF-NO.
+#
+# This macro #defines HAVE_LIBCURL if a working libcurl setup is
+# found, and sets @LIBCURL@ and @LIBCURL_CPPFLAGS@ to the necessary
+# values.  Other useful defines are LIBCURL_FEATURE_xxx where xxx are
+# the various features supported by libcurl, and LIBCURL_PROTOCOL_yyy
+# where yyy are the various protocols supported by libcurl.  Both xxx
+# and yyy are capitalized.  See the list of AH_TEMPLATEs at the top of
+# the macro for the complete list of possible defines.  Shell
+# variables $libcurl_feature_xxx and $libcurl_protocol_yyy are also
+# defined to 'yes' for those features and protocols that were found.
+# Note that xxx and yyy keep the same capitalization as in the
+# curl-config list (e.g. it's "HTTP" and not "http").
+#
+# Users may override the detected values by doing something like:
+# LIBCURL="-lcurl" LIBCURL_CPPFLAGS="-I/usr/myinclude" ./configure
+#
+# For the sake of sanity, this macro assumes that any libcurl that is
+# found is after version 7.7.2, the first version that included the
+# curl-config script.  Note that it is very important for people
+# packaging binary versions of libcurl to include this script!
+# Without curl-config, we can only guess what protocols are available,
+# or use curl_version_info to figure it out at runtime.
+
+AC_DEFUN([LIBCURL_CHECK_CONFIG],
+[
+  AH_TEMPLATE([LIBCURL_FEATURE_SSL],[Defined if libcurl supports SSL])
+  AH_TEMPLATE([LIBCURL_FEATURE_KRB4],[Defined if libcurl supports KRB4])
+  AH_TEMPLATE([LIBCURL_FEATURE_IPV6],[Defined if libcurl supports IPv6])
+  AH_TEMPLATE([LIBCURL_FEATURE_LIBZ],[Defined if libcurl supports libz])
+  AH_TEMPLATE([LIBCURL_FEATURE_ASYNCHDNS],[Defined if libcurl supports AsynchDNS])
+  AH_TEMPLATE([LIBCURL_FEATURE_IDN],[Defined if libcurl supports IDN])
+  AH_TEMPLATE([LIBCURL_FEATURE_SSPI],[Defined if libcurl supports SSPI])
+  AH_TEMPLATE([LIBCURL_FEATURE_NTLM],[Defined if libcurl supports NTLM])
+
+  AH_TEMPLATE([LIBCURL_PROTOCOL_HTTP],[Defined if libcurl supports HTTP])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_HTTPS],[Defined if libcurl supports HTTPS])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_FTP],[Defined if libcurl supports FTP])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_FTPS],[Defined if libcurl supports FTPS])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_FILE],[Defined if libcurl supports FILE])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_TELNET],[Defined if libcurl supports TELNET])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_LDAP],[Defined if libcurl supports LDAP])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_DICT],[Defined if libcurl supports DICT])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_TFTP],[Defined if libcurl supports TFTP])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_RTSP],[Defined if libcurl supports RTSP])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_POP3],[Defined if libcurl supports POP3])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_IMAP],[Defined if libcurl supports IMAP])
+  AH_TEMPLATE([LIBCURL_PROTOCOL_SMTP],[Defined if libcurl supports SMTP])
+
+  AC_ARG_WITH(libcurl,
+     AS_HELP_STRING([--with-libcurl=PREFIX],[look for the curl library in PREFIX/lib and headers in PREFIX/include]),
+     [_libcurl_with=$withval],[_libcurl_with=ifelse([$1],,[yes],[$1])])
+
+  if test "$_libcurl_with" != "no" ; then
+
+     AC_PROG_AWK
+
+     _libcurl_version_parse="eval $AWK '{split(\$NF,A,\".\"); X=256*256*A[[1]]+256*A[[2]]+A[[3]]; print X;}'"
+
+     _libcurl_try_link=yes
+
+     if test -d "$_libcurl_with" ; then
+        LIBCURL_CPPFLAGS="-I$withval/include"
+        _libcurl_ldflags="-L$withval/lib"
+        AC_PATH_PROG([_libcurl_config],[curl-config],[],
+                     ["$withval/bin"])
+     else
+        AC_PATH_PROG([_libcurl_config],[curl-config],[],[$PATH])
+     fi
+
+     if test x$_libcurl_config != "x" ; then
+        AC_CACHE_CHECK([for the version of libcurl],
+           [libcurl_cv_lib_curl_version],
+           [libcurl_cv_lib_curl_version=`$_libcurl_config --version | $AWK '{print $[]2}'`])
+
+        _libcurl_version=`echo $libcurl_cv_lib_curl_version | $_libcurl_version_parse`
+        _libcurl_wanted=`echo ifelse([$2],,[0],[$2]) | $_libcurl_version_parse`
+
+        if test $_libcurl_wanted -gt 0 ; then
+           AC_CACHE_CHECK([for libcurl >= version $2],
+              [libcurl_cv_lib_version_ok],
+              [
+              if test $_libcurl_version -ge $_libcurl_wanted ; then
+                 libcurl_cv_lib_version_ok=yes
+              else
+                 libcurl_cv_lib_version_ok=no
+              fi
+              ])
+        fi
+
+        if test $_libcurl_wanted -eq 0 || test x$libcurl_cv_lib_version_ok = xyes ; then
+           if test x"$LIBCURL_CPPFLAGS" = "x" ; then
+              LIBCURL_CPPFLAGS=`$_libcurl_config --cflags`
+           fi
+           if test x"$LIBCURL" = "x" ; then
+              if $5; then
+                 case "$host_os" in
+                 darwin*)
+                    LIBCURL=`$_libcurl_config --libs`
+                    ;;
+                 *)
+                    LIBCURL=`$_libcurl_config --static-libs`
+                    ;;
+                 esac
+              else
+                 LIBCURL=`$_libcurl_config --libs`
+              fi
+
+              # This is so silly, but Apple actually has a bug in their
+              # curl-config script.  Fixed in Tiger, but there are still
+              # lots of Panther installs around.
+              case "${host}" in
+                 powerpc-apple-darwin7*)
+                    LIBCURL=`echo $LIBCURL | sed -e 's|-arch i386||g'`
+                 ;;
+              esac
+           fi
+
+           dnl If we are on OS X and we haven't picked up libcurl static or
+           dnl otherwise, then let's just go ahead and use the one present on
+           dnl the system. Since this compiled binary will only run on OS X
+           dnl which almost always has cURL installed, it's OK to add the
+           dnl static dependency.
+           AS_IF([test "x${LIBCURL}" = "x"],
+                [AS_CASE(["$host_os"],
+                    [darwin*],
+                    [AS_IF([test "x$_libcurl_config" != "x"],
+                        AS_VAR_SET(LIBCURL, $($_libcurl_config --libs)),
+                        []
+                    )],
+                    []
+                )],
+                []
+            )
+
+           # All curl-config scripts support --feature
+           _libcurl_features=`$_libcurl_config --feature`
+
+           # Is it modern enough to have --protocols? (7.12.4)
+           if test $_libcurl_version -ge 461828 ; then
+              _libcurl_protocols=`$_libcurl_config --protocols`
+           fi
+        else
+           _libcurl_try_link=no
+        fi
+
+        unset _libcurl_wanted
+     fi
+
+     if test $_libcurl_try_link = yes ; then
+
+        # we didn't find curl-config, so let's see if the user-supplied
+        # link line (or failing that, "-lcurl") is enough.
+        # LIBCURL=${LIBCURL-"$_libcurl_ldflags -lcurl"}
+
+        AC_CACHE_CHECK([whether libcurl is usable],
+           [libcurl_cv_lib_curl_usable],
+           [
+           _libcurl_save_cppflags=$CPPFLAGS
+           CPPFLAGS="$LIBCURL_CPPFLAGS $CPPFLAGS"
+           _libcurl_save_libs=$LIBS
+           LIBS="$_libcurl_ldflags $LIBCURL $LIBS"
+
+           AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <curl/curl.h>]],[[
+/* Try and use a few common options to force a failure if we are
+   missing symbols or can't link. */
+int x;
+curl_easy_setopt(NULL,CURLOPT_URL,NULL);
+x=CURL_ERROR_SIZE;
+x=CURLOPT_WRITEFUNCTION;
+x=CURLOPT_WRITEDATA;
+x=CURLOPT_ERRORBUFFER;
+x=CURLOPT_STDERR;
+x=CURLOPT_VERBOSE;
+if (x) {;}
+]])],libcurl_cv_lib_curl_usable=yes,libcurl_cv_lib_curl_usable=no)
+
+           CPPFLAGS=$_libcurl_save_cppflags
+           LIBS=$_libcurl_save_libs
+           unset _libcurl_save_cppflags
+           unset _libcurl_save_libs
+           ])
+
+        if test $libcurl_cv_lib_curl_usable = yes ; then
+
+           # Does curl_free() exist in this version of libcurl?
+           # If not, fake it with free()
+
+           _libcurl_save_cppflags=$CPPFLAGS
+           CPPFLAGS="$CPPFLAGS $LIBCURL_CPPFLAGS"
+           _libcurl_save_libs=$LIBS
+           LIBS="$LIBS $LIBCURL"
+           LDFLAGS="$_libcurl_ldflags $LDFLAGS"
+
+           AC_CHECK_FUNC(curl_free,,
+              AC_DEFINE(curl_free,free,
+                [Define curl_free() as free() if our version of curl lacks curl_free.]))
+
+           CPPFLAGS=$_libcurl_save_cppflags
+           LIBS=$_libcurl_save_libs
+           unset _libcurl_save_cppflags
+           unset _libcurl_save_libs
+
+           AC_DEFINE(HAVE_LIBCURL,1,
+             [Define to 1 if you have a functional curl library.])
+           AC_SUBST(LIBCURL_CPPFLAGS)
+           AC_SUBST(LIBCURL)
+
+           for _libcurl_feature in $_libcurl_features ; do
+              AC_DEFINE_UNQUOTED(AS_TR_CPP(libcurl_feature_$_libcurl_feature),[1])
+              eval AS_TR_SH(libcurl_feature_$_libcurl_feature)=yes
+           done
+
+           if test "x$_libcurl_protocols" = "x" ; then
+
+              # We don't have --protocols, so just assume that all
+              # protocols are available
+              _libcurl_protocols="HTTP FTP FILE TELNET LDAP DICT TFTP"
+
+              if test x$libcurl_feature_SSL = xyes ; then
+                 _libcurl_protocols="$_libcurl_protocols HTTPS"
+
+                 # FTPS wasn't standards-compliant until version
+                 # 7.11.0 (0x070b00 == 461568)
+                 if test $_libcurl_version -ge 461568; then
+                    _libcurl_protocols="$_libcurl_protocols FTPS"
+                 fi
+              fi
+
+              # RTSP, IMAP, POP3 and SMTP were added in
+              # 7.20.0 (0x071400 == 463872)
+              if test $_libcurl_version -ge 463872; then
+                 _libcurl_protocols="$_libcurl_protocols RTSP IMAP POP3 SMTP"
+              fi
+           fi
+
+           for _libcurl_protocol in $_libcurl_protocols ; do
+              AC_DEFINE_UNQUOTED(AS_TR_CPP(libcurl_protocol_$_libcurl_protocol),[1])
+              eval AS_TR_SH(libcurl_protocol_$_libcurl_protocol)=yes
+           done
+        else
+           unset LIBCURL
+           unset LIBCURL_CPPFLAGS
+        fi
+     fi
+
+     unset _libcurl_try_link
+     unset _libcurl_version_parse
+     unset _libcurl_config
+     unset _libcurl_feature
+     unset _libcurl_features
+     unset _libcurl_protocol
+     unset _libcurl_protocols
+     unset _libcurl_version
+     unset _libcurl_ldflags
+  fi
+
+  if test x$_libcurl_with = xno || test x$libcurl_cv_lib_curl_usable != xyes ; then
+     # This is the IF-NO path
+     ifelse([$4],,:,[$4])
+  else
+     # This is the IF-YES path
+     ifelse([$3],,:,[$3])
+  fi
+
+  unset _libcurl_with
+])dnl
diff --git a/m4/lnav_common.m4 b/m4/lnav_common.m4
new file mode 100644
index 0000000..1619afe
--- /dev/null
+++ b/m4/lnav_common.m4
@@ -0,0 +1,22 @@
+AC_DEFUN([LNAV_ADDTO], [
+  if test "x$$1" = "x"; then
+    test "x$verbose" = "xyes" && echo "  setting $1 to \"$2\""
+    $1="$2"
+  else
+    ats_addto_bugger="$2"
+    for i in $ats_addto_bugger; do
+      ats_addto_duplicate="0"
+      for j in $$1; do
+        if test "x$i" = "x$j"; then
+          ats_addto_duplicate="1"
+          break
+        fi
+      done
+      if test $ats_addto_duplicate = "0"; then
+        test "x$verbose" = "xyes" && echo "  adding \"$i\" to $1"
+        $1="$$1 $i"
+      fi
+    done
+  fi
+])dnl
+
diff --git a/m4/lnav_with_jemalloc.m4 b/m4/lnav_with_jemalloc.m4
new file mode 100644
index 0000000..99103eb
--- /dev/null
+++ b/m4/lnav_with_jemalloc.m4
@@ -0,0 +1,81 @@
+dnl -------------------------------------------------------- -*- autoconf -*-
+dnl Licensed to the Apache Software Foundation (ASF) under one or more
+dnl contributor license agreements.  See the NOTICE file distributed with
+dnl this work for additional information regarding copyright ownership.
+dnl The ASF licenses this file to You under the Apache License, Version 2.0
+dnl (the "License"); you may not use this file except in compliance with
+dnl the License.  You may obtain a copy of the License at
+dnl
+dnl     http://www.apache.org/licenses/LICENSE-2.0
+dnl
+dnl Unless required by applicable law or agreed to in writing, software
+dnl distributed under the License is distributed on an "AS IS" BASIS,
+dnl WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+dnl See the License for the specific language governing permissions and
+dnl limitations under the License.
+
+dnl
+dnl lnav_with_jemalloc.m4: lnav's jemalloc autoconf macros
+dnl
+dnl
+AC_DEFUN([LNAV_WITH_JEMALLOC], [
+enable_jemalloc=no
+AC_ARG_WITH([jemalloc],
+    [AS_HELP_STRING([--with-jemalloc=DIR],[use a specific jemalloc library])],
+[
+    if test "$withval" != "no"; then
+        enable_jemalloc=yes
+        modify_env_variables=no
+        case "$withval" in
+            yes)
+                AC_MSG_NOTICE([Checking for jemalloc libs])
+                ;;
+            *)
+                jemalloc_include="$withval/include"
+                jemalloc_ldflags="$withval/lib"
+                modify_env_variables="yes"
+                AC_MSG_NOTICE([Checking for jemalloc libs in $withval])
+                ;;
+        esac
+    fi
+])
+
+jemalloch=0
+if test "$enable_jemalloc" != "no"; then
+    saved_ldflags=$LDFLAGS
+    saved_cppflags=$CPPFLAGS
+    saved_libtool_link_flags=$LIBTOOL_LINK_FLAGS
+    jemalloc_have_headers=0
+    jemalloc_have_libs=0
+
+    if test "$modify_env_variables" != "no"; then
+        LNAV_ADDTO(CPPFLAGS, [-I${jemalloc_include}])
+        LNAV_ADDTO(LDFLAGS, [-L${jemalloc_ldflags}])
+        LNAV_ADDTO(LIBTOOL_LINK_FLAGS, [-R${jemalloc_ldflags}])
+    fi
+    # On Darwin, jemalloc symbols are prefixed with je_. Search for that first,
+    # then fall back to unadorned symbols.
+    AC_SEARCH_LIBS([je_malloc_stats_print], [jemalloc], [jemalloc_have_libs=1],
+        [AC_SEARCH_LIBS([malloc_stats_print], [jemalloc], [jemalloc_have_libs=1])]
+    )
+    if test "$jemalloc_have_libs" != "0"; then
+        AC_MSG_NOTICE([Checking for jemalloc includes])
+        AC_CHECK_HEADERS(jemalloc/jemalloc.h, [jemalloc_have_headers=1])
+        if test "$jemalloc_have_headers" != "0"; then
+            jemalloch=1
+            LNAV_ADDTO(LIBS, [-ljemalloc])
+        else
+            AC_MSG_WARN([jemalloc headers not found])
+        fi
+    else
+        AC_MSG_WARN([jemalloc libs not found])
+    fi
+    if test "$jemalloc_have_libs" = "0"; then
+        CPPFLAGS=$saved_cppflags
+        LDFLAGS=$saved_ldflags
+        LIBTOOL_LINK_FLAGS=$saved_libtool_link_flags
+        AC_MSG_WARN([jemalloc not found])
+    fi
+fi
+AC_SUBST(jemalloch)
+])dnl
diff --git a/m4/lnav_with_libarchive.m4 b/m4/lnav_with_libarchive.m4
new file mode 100644
index 0000000..a6fa4fd
--- /dev/null
+++ b/m4/lnav_with_libarchive.m4
@@ -0,0 +1,77 @@
+dnl
+dnl Copyright (c) 2020, Timothy Stack
+dnl
+dnl All rights reserved.
+dnl
+dnl Redistribution and use in source and binary forms, with or without
+dnl modification, are permitted provided that the following conditions are met:
+dnl
+dnl dnl Redistributions of source code must retain the above copyright notice, this
+dnl list of conditions and the following disclaimer.
+dnl dnl Redistributions in binary form must reproduce the above copyright notice,
+dnl this list of conditions and the following disclaimer in the documentation
+dnl and/or other materials provided with the distribution.
+dnl dnl Neither the name of Timothy Stack nor the names of its contributors
+dnl may be used to endorse or promote products derived from this software
+dnl without specific prior written permission.
+dnl
+dnl THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
+dnl EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+dnl WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+dnl DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+dnl DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+dnl (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+dnl LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+dnl ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+dnl (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+dnl SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+dnl
+dnl @file lnav_with_libarchive.m4
+dnl
+AC_DEFUN([AX_PATH_LIB_ARCHIVE],[dnl
+AC_MSG_CHECKING([lib archive])
+AC_ARG_WITH(libarchive,
+[  --with-libarchive[[=prefix]]],,
+     with_libarchive="yes")
+if test ".$with_libarchive" = ".no" ; then
+  AC_MSG_RESULT([disabled])
+  m4_ifval($2,$2)
+else
+  AC_MSG_RESULT([(testing)])
+  AC_CHECK_LIB(archive, archive_read_new)
+  AC_CHECK_HEADERS(archive.h)
+  if test "$ac_cv_lib_archive_archive_read_new" = "yes" && \
+     test "x$ac_cv_header_archive_h" = xyes; then
+     LIBARCHIVE_LIBS="-larchive"
+     AC_MSG_CHECKING([lib archive])
+     AC_MSG_RESULT([$LIBARCHIVE_LIBS])
+     m4_ifval($1,$1)
+  else
+     unset ac_cv_header_archive_h
+     OLDLDFLAGS="$LDFLAGS" ; LDFLAGS="$LDFLAGS -L$with_libarchive/lib"
+     OLDCPPFLAGS="$CPPFLAGS" ; CPPFLAGS="$CPPFLAGS -I$with_libarchive/include"
+     AC_CHECK_LIB(archive, archive_read_new)
+     AC_CHECK_HEADERS(archive.h)
+     CPPFLAGS="$OLDCPPFLAGS"
+     LDFLAGS="$OLDLDFLAGS"
+     if test "$ac_cv_lib_archive_archive_read_new" = "yes" && \
+        test "x$ac_cv_header_archive_h" = xyes; then
+        AC_MSG_RESULT(.setting LIBARCHIVE_LIBS -L$with_libarchive/lib -larchive)
+        LIBARCHIVE_LDFLAGS="-L$with_libarchive/lib"
+        LIBARCHIVE_LIBS="-larchive"
+        test -d "$with_libarchive/include" && LIBARCHIVE_CFLAGS="-I$with_libarchive/include"
+        AC_MSG_CHECKING([lib archive])
+        AC_MSG_RESULT([$LIBARCHIVE_LIBS])
+        m4_ifval($1,$1)
+     else
+        AC_MSG_CHECKING([lib archive])
+        AC_MSG_RESULT([[no]])
+        m4_ifval($2,$2)
+     fi
+  fi
+fi
+AC_SUBST([LIBARCHIVE_LIBS])
+AC_SUBST([LIBARCHIVE_LDFLAGS])
+AC_SUBST([LIBARCHIVE_CFLAGS])
+])
+
diff --git a/m4/lnav_with_readline.m4 b/m4/lnav_with_readline.m4
new file mode 100644
index 0000000..217391c
--- /dev/null
+++ b/m4/lnav_with_readline.m4
@@ -0,0 +1,95 @@
+dnl
+dnl Copyright (c) 2007-2015, Timothy Stack
+dnl Copyright (c) 2015, Suresh Sundriyal
+dnl
+dnl All rights reserved.
+dnl
+dnl Redistribution and use in source and binary forms, with or without
+dnl modification, are permitted provided that the following conditions are met:
+dnl
+dnl dnl Redistributions of source code must retain the above copyright notice, this
+dnl list of conditions and the following disclaimer.
+dnl dnl Redistributions in binary form must reproduce the above copyright notice,
+dnl this list of conditions and the following disclaimer in the documentation
+dnl and/or other materials provided with the distribution.
+dnl dnl Neither the name of Timothy Stack nor the names of its contributors
+dnl may be used to endorse or promote products derived from this software
+dnl without specific prior written permission.
+dnl
+dnl THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
+dnl EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+dnl WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+dnl DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+dnl DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+dnl (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+dnl LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+dnl ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+dnl (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+dnl SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+dnl
+dnl @file lnav_with_readline.m4
+dnl
+AC_DEFUN([AX_PATH_LIB_READLINE],
+    [dnl
+    AC_REQUIRE([AX_WITH_CURSES])
+    AC_MSG_CHECKING([lib readline])
+    AC_ARG_WITH([readline],
+        AS_HELP_STRING([--with-readline@<:@=prefix@:>@],dnl
+            [compile xmlreadline part (via libreadline check)]),
+        [],
+        [with_readline="yes"]
+    )dnl
+
+    AS_VAR_SET(saved_CFLAGS, $CFLAGS)
+    AS_VAR_SET(saved_CPPFLAGS, $CPPFLAGS)
+    AS_VAR_SET(saved_LDFLAGS, $LDFLAGS)
+    AS_VAR_SET(saved_LIBS, $LIBS)
+    AS_CASE(["$with_readline"],
+        [no],
+        AC_MSG_ERROR([readline required to build]),
+        [yes],
+        [],
+        [dnl
+        AS_VAR_SET([READLINE_CFLAGS], ["-I$with_readline/include"])
+        AS_VAR_SET([READLINE_LDFLAGS], ["-L$with_readline/lib"])
+        LNAV_ADDTO(CFLAGS, [-I$with_readline/include])
+        LNAV_ADDTO(CPPFLAGS, [-I$with_readline/include])
+        dnl We want the provided path to be the first in the search order.
+        LDFLAGS="-L$with_readline/lib $LDFLAGS"
+        ]dnl
+    )
+
+    AC_SEARCH_LIBS([readline], [readline],
+        [AS_VAR_SET([READLINE_LIBS], ["-lreadline"])],
+        [AC_MSG_ERROR([libreadline library not found])],
+        [$CURSES_LIB]dnl
+    )dnl
+
+    dnl Ensure that the readline library has the required symbols.
+    dnl i.e. We haven't picked up editline.
+    AC_SEARCH_LIBS([history_set_history_state], [readline],
+        [],
+        AC_MSG_ERROR([libreadline does not have the required symbols. editline possibly masquerading as readline.]),
+        [$CURSES_LIB]dnl
+    )
+
+    AC_CHECK_HEADERS([readline.h readline/readline.h],
+        [dnl
+        AS_VAR_SET([HAVE_READLINE_HEADERS], [1])
+        break
+        ]dnl
+    )
+
+    AS_VAR_SET_IF([HAVE_READLINE_HEADERS], [],
+        [AC_MSG_ERROR([readline headers not found])]
+    )
+    AS_VAR_SET(CFLAGS, $saved_CFLAGS)
+    AS_VAR_SET(CPPFLAGS, $saved_CPPFLAGS)
+    AS_VAR_SET(LDFLAGS, $saved_LDFLAGS)
+    AS_VAR_SET(LIBS, $saved_LIBS)
+
+    AC_SUBST([READLINE_LIBS])
+    AC_SUBST([READLINE_CFLAGS])
+    AC_SUBST([READLINE_LDFLAGS])
+    ]dnl
+)dnl
diff --git a/m4/lnav_with_sqlite3.m4 b/m4/lnav_with_sqlite3.m4
new file mode 100644
index 0000000..6eaa9fa
--- /dev/null
+++ b/m4/lnav_with_sqlite3.m4
@@ -0,0 +1,127 @@
+dnl
+dnl @Modified from: ax_sqlite3.m4
+dnl @author Mateusz Loskot <mateusz@loskot.net>
+dnl @version $Date: 2006/08/30 14:28:55 $
+dnl @license AllPermissive
+dnl
+dnl Copyright (c) 2015, Suresh Sundriyal
+dnl
+dnl @file lnav_with_sqlite3.m4
+dnl
+AC_DEFUN([LNAV_WITH_SQLITE3],
+[dnl
+    AC_ARG_WITH([sqlite3],
+        AS_HELP_STRING([--with-sqlite3=@<:@prefix@:>@],[compile with sqlite3]),
+        [],
+        [with_sqlite3="yes"]
+    )
+
+    AS_VAR_SET(saved_CFLAGS, $CFLAGS)
+    AS_VAR_SET(saved_CPPFLAGS, $CPPFLAGS)
+    AS_VAR_SET(saved_LDFLAGS, $LDFLAGS)
+    AS_VAR_SET(saved_LIBS, $LIBS)
+
+    AS_CASE(["$with_sqlite3"],
+        [no],
+        AC_MSG_ERROR([sqlite3 required to build]),
+        [yes],
+        [],
+        [dnl
+        LNAV_ADDTO(CFLAGS, [-I$with_sqlite3/include])
+        LNAV_ADDTO(CPPFLAGS, [-I$with_sqlite3/include])
+        AS_VAR_SET([SQLITE3_LDFLAGS], ["-L$with_sqlite3/lib"])
+        AS_VAR_SET([SQLITE3_CFLAGS], ["-I$with_sqlite3/include"])
+        LDFLAGS="-L$with_sqlite3/lib $LDFLAGS"
+        ]
+    )
+
+    AC_SEARCH_LIBS([sqlite3_open], [sqlite3],
+        AS_VAR_SET([SQLITE3_LIBS], ["-lsqlite3"]),
+        AC_MSG_ERROR([sqlite3 library not found]),
+        [-pthread]dnl
+    )
+
+    AC_CHECK_HEADERS([sqlite3.h], [],
+        AC_MSG_ERROR([sqlite3 headers not found])
+    )
+
+    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])
+    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])
+        ],
+        [
+        AC_MSG_RESULT([not found])
+        AC_MSG_ERROR([SQLite3 version >= $sqlite3_version_req is required])
+        ]
+    )
+    AC_LANG_POP([C++])
+
+    AC_CHECK_FUNC(sqlite3_stmt_readonly,
+        AC_DEFINE([HAVE_SQLITE3_STMT_READONLY], [1],
+            [Have the sqlite3_stmt_readonly function]
+        )
+    )
+
+    AC_CHECK_FUNC(sqlite3_value_subtype,
+        HAVE_SQLITE3_VALUE_SUBTYPE=1
+        AC_DEFINE([HAVE_SQLITE3_VALUE_SUBTYPE], [1],
+            [Have the sqlite3_value_subtype function]
+        )
+    )
+
+    AC_SUBST(HAVE_SQLITE3_VALUE_SUBTYPE)
+
+    AC_CHECK_FUNC(sqlite3_error_offset,
+        HAVE_SQLITE3_ERROR_OFFSET=1
+        AC_DEFINE([HAVE_SQLITE3_ERROR_OFFSET], [1],
+            [Have the sqlite3_error_offset function]
+        )
+    )
+
+    AC_SUBST(HAVE_SQLITE3_ERROR_OFFSET)
+
+    AC_CHECK_FUNC(sqlite3_drop_modules,
+        HAVE_SQLITE3_DROP_MODULES=1
+        AC_DEFINE([HAVE_SQLITE3_DROP_MODULES], [1],
+            [Have the sqlite3_drop_modules function]
+        )
+    )
+
+    AC_SUBST(HAVE_SQLITE3_DROP_MODULES)
+
+    AS_VAR_SET(CFLAGS, $saved_CFLAGS)
+    AS_VAR_SET(CPPFLAGS, $saved_CPPFLAGS)
+    AS_VAR_SET(LDFLAGS, $saved_LDFLAGS)
+    AS_VAR_SET(LIBS, $saved_LIBS)
+
+    AC_SUBST(SQLITE3_CFLAGS)
+    AC_SUBST(SQLITE3_LDFLAGS)
+    AC_SUBST(SQLITE3_LIBS)
+]
+)
diff --git a/m4/lnav_with_yajl.m4 b/m4/lnav_with_yajl.m4
new file mode 100644
index 0000000..0f9d942
--- /dev/null
+++ b/m4/lnav_with_yajl.m4
@@ -0,0 +1,87 @@
+dnl
+dnl Copyright (c) 2015, Suresh Sundriyal
+dnl
+dnl All rights reserved.
+dnl
+dnl Redistribution and use in source and binary forms, with or without
+dnl modification, are permitted provided that the following conditions are met:
+dnl
+dnl dnl Redistributions of source code must retain the above copyright notice, this
+dnl list of conditions and the following disclaimer.
+dnl dnl Redistributions in binary form must reproduce the above copyright notice,
+dnl this list of conditions and the following disclaimer in the documentation
+dnl and/or other materials provided with the distribution.
+dnl dnl Neither the name of Timothy Stack nor the names of its contributors
+dnl may be used to endorse or promote products derived from this software
+dnl without specific prior written permission.
+dnl
+dnl THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
+dnl EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+dnl WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+dnl DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+dnl DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+dnl (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+dnl LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+dnl ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+dnl (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+dnl SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+dnl
+dnl @file lnav_with_yajl.m4
+AC_DEFUN([LNAV_WITH_LOCAL_YAJL],
+    [
+    AC_ARG_WITH([yajl],
+        AS_HELP_STRING([--with-yajl=DIR],[use a local installed version of yajl]),
+        [
+        AS_IF([test "$withval" != "no"],
+            [
+            AS_CASE(["$withval"],
+                [yes],
+                [AC_MSG_NOTICE([Checking for yajl libs])],
+                [
+                AS_VAR_SET([yajl_saved_ldflags], ["$LDFLAGS"])
+                AS_VAR_SET([yajl_saved_cppflags], ["$CPPFLAGS"])
+                AS_VAR_SET([yajl_saved_libtool_link_flags],
+                    ["$LIBTOOL_LIBK_FLAGS"]
+                )
+
+                LNAV_ADDTO(CPPFLAGS, [-I$withval/include])
+                LNAV_ADDTO(LDFLAGS, [-I$withval/lib])
+                LNAV_ADDTO(LIBTOOL_LINK_FLAGS, [-R$withval/lib])
+
+                AC_MSG_NOTICE([Checking for yajl libs in $withval])
+                ]
+            )
+
+            AC_SEARCH_LIBS([yajl_gen_alloc],
+                [yajl],
+                [
+                AC_MSG_NOTICE([Checking for yajl headers])
+                AC_CHECK_HEADERS([yajl/yajl_parse.h],
+                    AS_VAR_SET([HAVE_LOCAL_YAJL], [1]),
+                    AC_MSG_WARN([yajl not found on the local system])
+                )
+                ]
+            )
+            ]
+        )
+        ]
+    )
+
+    AS_VAR_SET_IF([HAVE_LOCAL_YAJL],
+        [],
+        [
+        AC_MSG_NOTICE([compiling with the included version of yajl])
+        AS_VAR_SET([HAVE_LOCAL_YAJL], [0])
+        AS_VAR_SET_IF([yajl_saved_ldflags],
+            [
+            AS_VAR_SET([CPPFLAGS], ["$yajl_saved_cppflags"])
+            AS_VAR_SET([LDFLAGS], ["$yajl_saved_ldflags"])
+            AS_VAR_SET([LIBTOOL_LIBK_FLAGS], ["$yajl_saved_libtool_link_flags"])
+            ]
+        )
+        ]
+    )
+
+    AC_SUBST(HAVE_LOCAL_YAJL)
+    ]
+)dnl