--- /dev/null
+# ===========================================================================
+# http://www.gnu.org/software/autoconf-archive/ax_compare_version.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+# AX_COMPARE_VERSION(VERSION_A, OP, VERSION_B, [ACTION-IF-TRUE], [ACTION-IF-FALSE])
+#
+# DESCRIPTION
+#
+# This macro compares two version strings. Due to the various number of
+# minor-version numbers that can exist, and the fact that string
+# comparisons are not compatible with numeric comparisons, this is not
+# necessarily trivial to do in a autoconf script. This macro makes doing
+# these comparisons easy.
+#
+# The six basic comparisons are available, as well as checking equality
+# limited to a certain number of minor-version levels.
+#
+# The operator OP determines what type of comparison to do, and can be one
+# of:
+#
+# eq - equal (test A == B)
+# ne - not equal (test A != B)
+# le - less than or equal (test A <= B)
+# ge - greater than or equal (test A >= B)
+# lt - less than (test A < B)
+# gt - greater than (test A > B)
+#
+# Additionally, the eq and ne operator can have a number after it to limit
+# the test to that number of minor versions.
+#
+# eq0 - equal up to the length of the shorter version
+# ne0 - not equal up to the length of the shorter version
+# eqN - equal up to N sub-version levels
+# neN - not equal up to N sub-version levels
+#
+# When the condition is true, shell commands ACTION-IF-TRUE are run,
+# otherwise shell commands ACTION-IF-FALSE are run. The environment
+# variable 'ax_compare_version' is always set to either 'true' or 'false'
+# as well.
+#
+# Examples:
+#
+# AX_COMPARE_VERSION([3.15.7],[lt],[3.15.8])
+# AX_COMPARE_VERSION([3.15],[lt],[3.15.8])
+#
+# would both be true.
+#
+# AX_COMPARE_VERSION([3.15.7],[eq],[3.15.8])
+# AX_COMPARE_VERSION([3.15],[gt],[3.15.8])
+#
+# would both be false.
+#
+# AX_COMPARE_VERSION([3.15.7],[eq2],[3.15.8])
+#
+# would be true because it is only comparing two minor versions.
+#
+# AX_COMPARE_VERSION([3.15.7],[eq0],[3.15])
+#
+# would be true because it is only comparing the lesser number of minor
+# versions of the two values.
+#
+# Note: The characters that separate the version numbers do not matter. An
+# empty string is the same as version 0. OP is evaluated by autoconf, not
+# configure, so must be a string, not a variable.
+#
+# The author would like to acknowledge Guido Draheim whose advice about
+# the m4_case and m4_ifvaln functions make this macro only include the
+# portions necessary to perform the specific comparison specified by the
+# OP argument in the final configure script.
+#
+# LICENSE
+#
+# Copyright (c) 2008 Tim Toolan <toolan@ele.uri.edu>
+#
+# Copying and distribution of this file, with or without modification, are
+# permitted in any medium without royalty provided the copyright notice
+# and this notice are preserved. This file is offered as-is, without any
+# warranty.
+
+#serial 11
+
+dnl #########################################################################
+AC_DEFUN([AX_COMPARE_VERSION], [
+ AC_REQUIRE([AC_PROG_AWK])
+
+ # Used to indicate true or false condition
+ ax_compare_version=false
+
+ # Convert the two version strings to be compared into a format that
+ # allows a simple string comparison. The end result is that a version
+ # string of the form 1.12.5-r617 will be converted to the form
+ # 0001001200050617. In other words, each number is zero padded to four
+ # digits, and non digits are removed.
+ AS_VAR_PUSHDEF([A],[ax_compare_version_A])
+ A=`echo "$1" | sed -e 's/\([[0-9]]*\)/Z\1Z/g' \
+ -e 's/Z\([[0-9]]\)Z/Z0\1Z/g' \
+ -e 's/Z\([[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+ -e 's/Z\([[0-9]][[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+ -e 's/[[^0-9]]//g'`
+
+ AS_VAR_PUSHDEF([B],[ax_compare_version_B])
+ B=`echo "$3" | sed -e 's/\([[0-9]]*\)/Z\1Z/g' \
+ -e 's/Z\([[0-9]]\)Z/Z0\1Z/g' \
+ -e 's/Z\([[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+ -e 's/Z\([[0-9]][[0-9]][[0-9]]\)Z/Z0\1Z/g' \
+ -e 's/[[^0-9]]//g'`
+
+ dnl # In the case of le, ge, lt, and gt, the strings are sorted as necessary
+ dnl # then the first line is used to determine if the condition is true.
+ dnl # The sed right after the echo is to remove any indented white space.
+ m4_case(m4_tolower($2),
+ [lt],[
+ ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort -r | sed "s/x${A}/false/;s/x${B}/true/;1q"`
+ ],
+ [gt],[
+ ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort | sed "s/x${A}/false/;s/x${B}/true/;1q"`
+ ],
+ [le],[
+ ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort | sed "s/x${A}/true/;s/x${B}/false/;1q"`
+ ],
+ [ge],[
+ ax_compare_version=`echo "x$A
+x$B" | sed 's/^ *//' | sort -r | sed "s/x${A}/true/;s/x${B}/false/;1q"`
+ ],[
+ dnl Split the operator from the subversion count if present.
+ m4_bmatch(m4_substr($2,2),
+ [0],[
+ # A count of zero means use the length of the shorter version.
+ # Determine the number of characters in A and B.
+ ax_compare_version_len_A=`echo "$A" | $AWK '{print(length)}'`
+ ax_compare_version_len_B=`echo "$B" | $AWK '{print(length)}'`
+
+ # Set A to no more than B's length and B to no more than A's length.
+ A=`echo "$A" | sed "s/\(.\{$ax_compare_version_len_B\}\).*/\1/"`
+ B=`echo "$B" | sed "s/\(.\{$ax_compare_version_len_A\}\).*/\1/"`
+ ],
+ [[0-9]+],[
+ # A count greater than zero means use only that many subversions
+ A=`echo "$A" | sed "s/\(\([[0-9]]\{4\}\)\{m4_substr($2,2)\}\).*/\1/"`
+ B=`echo "$B" | sed "s/\(\([[0-9]]\{4\}\)\{m4_substr($2,2)\}\).*/\1/"`
+ ],
+ [.+],[
+ AC_WARNING(
+ [illegal OP numeric parameter: $2])
+ ],[])
+
+ # Pad zeros at end of numbers to make same length.
+ ax_compare_version_tmp_A="$A`echo $B | sed 's/./0/g'`"
+ B="$B`echo $A | sed 's/./0/g'`"
+ A="$ax_compare_version_tmp_A"
+
+ # Check for equality or inequality as necessary.
+ m4_case(m4_tolower(m4_substr($2,0,2)),
+ [eq],[
+ test "x$A" = "x$B" && ax_compare_version=true
+ ],
+ [ne],[
+ test "x$A" != "x$B" && ax_compare_version=true
+ ],[
+ AC_WARNING([illegal OP parameter: $2])
+ ])
+ ])
+
+ AS_VAR_POPDEF([A])dnl
+ AS_VAR_POPDEF([B])dnl
+
+ dnl # Execute ACTION-IF-TRUE / ACTION-IF-FALSE.
+ if test "$ax_compare_version" = "true" ; then
+ m4_ifvaln([$4],[$4],[:])dnl
+ m4_ifvaln([$5],[else $5])dnl
+ fi
+]) dnl AX_COMPARE_VERSION
--- /dev/null
+# ===========================================================================
+# http://www.gnu.org/software/autoconf-archive/ax_prog_bison_version.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+# AX_PROG_BISON_VERSION([VERSION],[ACTION-IF-TRUE],[ACTION-IF-FALSE])
+#
+# DESCRIPTION
+#
+# Makes sure that bison version is greater or equal to the version
+# indicated. If true the shell commands in ACTION-IF-TRUE are executed. If
+# not the shell commands in commands in ACTION-IF-TRUE are executed. If
+# not the shell commands in ACTION-IF-FALSE are run. Note if $BISON is not
+# set (for example by running AC_CHECK_PROG or AC_PATH_PROG) the macro
+# will fail.
+#
+# Example:
+#
+# AC_PATH_PROG([BISON],[bison])
+# AX_PROG_BISON_VERSION([3.0.2],[ ... ],[ ... ])
+#
+# This will check to make sure that the bison you have is at least version
+# 3.0.2 or greater.
+#
+# NOTE: This macro uses the $BISON variable to perform the check.
+#
+# LICENSE
+#
+# Copyright (c) 2015 Jonathan Rajotte-Julien <jonathan.rajotte-julien@efficios.com>
+#
+# Copying and distribution of this file, with or without modification, are
+# permitted in any medium without royalty provided the copyright notice
+# and this notice are preserved. This file is offered as-is, without any
+# warranty.
+
+#serial 2
+
+AC_DEFUN([AX_PROG_BISON_VERSION],[
+ AC_REQUIRE([AC_PROG_SED])
+ AC_REQUIRE([AC_PROG_GREP])
+
+ AS_IF([test -n "$BISON"],[
+ ax_bison_version="$1"
+
+ AC_MSG_CHECKING([for bison version])
+ changequote(<<,>>)
+ bison_version=`$BISON --version 2>&1 \
+ | $SED -n -e '/bison (GNU Bison)/b inspect
+b
+: inspect
+s/.* (\{0,1\}\([0-9]*\.[0-9]*\.[0-9]*\))\{0,1\}.*/\1/;p'`
+ changequote([,])
+ AC_MSG_RESULT($bison_version)
+
+ AC_SUBST([BISON_VERSION],[$bison_version])
+
+ AX_COMPARE_VERSION([$bison_version],[ge],[$ax_bison_version],[
+ :
+ $2
+ ],[
+ :
+ $3
+ ])
+ ],[
+ AC_MSG_WARN([could not find bison])
+ $3
+ ])
+])