[vte] [configure] Make libtool versioning automatic

[Behdad Esfahbod <behdad src gnome org>]

commit 860ed187545355fa9daef60907a3746837cc7b6a
Author: Behdad Esfahbod <behdad behdad org>
Date:   Mon May 3 11:21:42 2010 -0400

    [configure] Make libtool versioning automatic

 configure.in |   21 +++++++++------------
 1 files changed, 9 insertions(+), 12 deletions(-)
---
diff --git a/configure.in b/configure.in
index 5f4ff7a..4483504 100644
--- a/configure.in
+++ b/configure.in
@@ -21,18 +21,15 @@ fi
 AM_MAINTAINER_MODE([enable])
 
 ################################################################################
-# Libtool shared library versioning stuffs.
-# REVISION gets incremented whenever the source code changes without adding
-# an API or ABI change.
-LTVERSION_REVISION=0
-# CURRENT must be incremented when an API or ABI change (addition or removal)
-# is made, and REVISION must be reset to 0 when this happens.
-LTVERSION_CURRENT=23
-# AGE must be incremented when an API or ABI addition is made, and REVISION
-# must be reset to 0 when this happens.
-LTVERSION_AGE=14
-
-LIBVTE_LTVERSION=${LTVERSION_CURRENT}:${LTVERSION_REVISION}:${LTVERSION_AGE}
+m4_if(m4_eval(vte_version_minor % 2), [1],
+      [   dnl for unstable releases
+	m4_define([lt_revision], 0)
+      ],[ dnl for stable releases
+	m4_define([lt_revision], vte_version_micro)
+      ])
+m4_define([lt_age], [m4_eval(vte_version_minor*100+vte_version_micro - lt_revision)])
+m4_define([lt_current], [m4_eval(9 + lt_age)]) dnl 9 is current major .so version
+LIBVTE_LTVERSION="lt_current():lt_revision():lt_age()"
 AC_SUBST([LIBVTE_LTVERSION])
 
 ################################################################################