Use 'git describe' for working builds

[zfs.git] / config / zfs-meta.m4

diff --git a/config/zfs-meta.m4 b/config/zfs-meta.m4
index a961657..2deda71 100644 (file)
--- a/config/zfs-meta.m4
+++ b/config/zfs-meta.m4
@@ -1,10 +1,14 @@
-dnl #
-dnl # ZFS_AC_META
-dnl # Read metadata from the META file.
-dnl #
-dnl # AUTHOR:
-dnl # Chris Dunlap <cdunlap@llnl.gov>
-dnl #
+###############################################################################
+# Written by Chris Dunlap <cdunlap@llnl.gov>.
+# Modified by Brian Behlendorf <behlendorf1@llnl.gov>.
+###############################################################################
+# ZFS_AC_META: Read metadata from the META file.  When building from a
+# git repository the ZFS_META_RELEASE field will be overwritten if there
+# is an annotated tag matching the form ZFS_META_NAME-ZFS_META_VERSION-*.
+# This allows for working builds to be uniquely identified using the git
+# commit hash.
+###############################################################################
+
 AC_DEFUN([ZFS_AC_META], [
 
        AH_BOTTOM([
@@ -20,9 +24,9 @@ AC_DEFUN([ZFS_AC_META], [
        AC_MSG_CHECKING([metadata])
 
        META="$srcdir/META"
-       _zfs_ac_meta_got_file=no
+       _zfs_ac_meta_type="none"
        if test -f "$META"; then
-               _zfs_ac_meta_got_file=yes
+               _zfs_ac_meta_type="META file"
 
                ZFS_META_NAME=_ZFS_AC_META_GETVAL([(?:NAME|PROJECT|PACKAGE)]);
                if test -n "$ZFS_META_NAME"; then
@@ -41,6 +45,16 @@ AC_DEFUN([ZFS_AC_META], [
                fi
 
                ZFS_META_RELEASE=_ZFS_AC_META_GETVAL([RELEASE]);
+               if git rev-parse --git-dir > /dev/null 2>&1; then
+                       _match="${ZFS_META_NAME}-${ZFS_META_VERSION}*"
+                       _alias=$(git describe --match=${_match} 2>/dev/null)
+                       _release=$(echo ${_alias}|cut -f3- -d'-'|sed 's/-/_/g')
+                       if test -n "${_release}"; then
+                               ZFS_META_RELEASE=${_release}
+                               _zfs_ac_meta_type="git describe"
+                       fi
+               fi
+
                if test -n "$ZFS_META_RELEASE"; then
                        AC_DEFINE_UNQUOTED([ZFS_META_RELEASE], ["$ZFS_META_RELEASE"],
                                [Define the project release.]
@@ -116,7 +130,7 @@ AC_DEFUN([ZFS_AC_META], [
                fi
        fi
 
-       AC_MSG_RESULT([$_zfs_ac_meta_got_file])
+       AC_MSG_RESULT([$_zfs_ac_meta_type])
        ]
 )