[caribou] libcaribou: Use libtool versioning

[Daiki Ueno <dueno src gnome org>]

commit 309475b2c8488062af761a6bd0a568cab2fb4a7a
Author: Daiki Ueno <dueno src gnome org>
Date:   Fri Nov 28 11:55:08 2014 +0900

    libcaribou: Use libtool versioning

 configure.ac           |   15 +++++++++++++++
 libcaribou/Makefile.am |    1 +
 2 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 641a4e2..ce3e2bb 100644
--- a/configure.ac
+++ b/configure.ac
@@ -8,6 +8,21 @@ AC_CONFIG_MACRO_DIR([m4])
 
 AM_PROG_LIBTOOL
 
+# If library source has changed since last release, increment revision
+# If public symbols have been added, removed or changed since last release,
+#  increment current and set revision to 0
+# If public symbols have been added since last release, increment age
+# If public symbols have been removed since last release, set age to 0
+m4_define([libcaribou_lt_current], [0])
+m4_define([libcaribou_lt_revision], [0])
+m4_define([libcaribou_lt_age], [0])
+LT_CURRENT=libcaribou_lt_current
+LT_REVISION=libcaribou_lt_revision
+LT_AGE=libcaribou_lt_age
+AC_SUBST([LT_CURRENT])
+AC_SUBST([LT_REVISION])
+AC_SUBST([LT_AGE])
+
 AM_INIT_AUTOMAKE([1.11 -Wno-portability dist-xz no-dist-gzip])
 AM_MAINTAINER_MODE([enable])
 # Support silent build rules. Disable by either passing --disable-silent-rules
diff --git a/libcaribou/Makefile.am b/libcaribou/Makefile.am
index 62a0a22..05f2774 100644
--- a/libcaribou/Makefile.am
+++ b/libcaribou/Makefile.am
@@ -17,6 +17,7 @@ libcaribou_la_CFLAGS = \
        $(LIBCARIBOU_CFLAGS)
 
 libcaribou_la_LDFLAGS = \
+        -version-info "$(LT_CURRENT)":"$(LT_REVISION)":"$(LT_AGE)" \
         -export-dynamic \
         -export-symbols $(srcdir)/libcaribou.symbols