# ===========================================================================
# http://autoconf-archive.cryp.to/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.
#
# LAST MODIFICATION
#
# 2008-04-12
#
# COPYLEFT
#
# 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.
dnl #########################################################################
AC_DEFUN([AX_COMPARE_VERSION], [
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