fix a mistake in the interpretation of CURRENT:AGE:REVISION meaning that could

lead to mis-versioning of the libraries.

diff --git a/configure.ac b/configure.ac
index e0c87c3..f7fceca 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -30,20 +30,27 @@ dnl         http://navi.cx/~mike/writing-shared-libraries.html
 dnl   * libtool.info chapter "Versioning"
 dnl ---------------------------------------------------------------------------
 dnl Versioning:
+dnl  - CURRENT (Major):  Increment if the interface has changes. AGE is always
+dnl                      *changed* at the same time.
 dnl  - AGE (Micro):      Increment if any interfaces have been added; set to 0
 dnl                     if any interfaces have been removed. Removal has 
 dnl                      precedence over adding, so set to 0 if both happened.
+dnl                      It denotes upward compatibility.
 dnl  - REVISION (Minor): Increment any time the source changes; set to 
 dnl                     0 if you incremented CURRENT.
-dnl  - CURRENT (Major):  Increment if the interface has changes or removals.
+dnl
+dnl  To summarize. Any interface *change* increment CURRENT. If that interface
+dnl  change does not break upward compatibility (ie it is an addition), 
+dnl  increment AGE, Otherwise AGE is reset to 0. If CURRENT has changed, 
+dnl  REVISION is set to 0, otherwise REVISION is incremented.
 dnl ---------------------------------------------------------------------------
-LIBEXIF_AGE=1
-LIBEXIF_REVISION=0
+LIBEXIF_AGE=0
+LIBEXIF_REVISION=1
 LIBEXIF_CURRENT=12
 AC_SUBST([LIBEXIF_AGE])
 AC_SUBST([LIBEXIF_REVISION])
 AC_SUBST([LIBEXIF_CURRENT])
-LIBEXIF_VERSION_INFO=`expr $LIBEXIF_CURRENT + $LIBEXIF_REVISION`:$LIBEXIF_AGE:$LIBEXIF_REVISION
+LIBEXIF_VERSION_INFO=$LIBEXIF_CURRENT:$LIBEXIF_REVISION:$LIBEXIF_AGE
 AC_SUBST([LIBEXIF_VERSION_INFO])
 
 AC_PROG_CC