# HG changeset patch
# User Jim Meyering <meyering@redhat.com>
# Date 1262273471 -3600
# Node ID dafd055586ef4692674c2d784f181d7f9486689f
# Parent  a8059f620e8f2b49e388dc6951caf604d5b74717
maint.mk: don't require explicit gpg_key_ID in cfg.mk

* top/maint.mk (gpg_key_ID): Derive key ID from signed release tag.
With this change, we can all remove the gpg_key_ID = ... definition
from our respective cfg.mk files.

diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2009-12-31  Jim Meyering  <meyering@redhat.com>
 
+	maint.mk: don't require explicit gpg_key_ID in cfg.mk
+	* top/maint.mk (gpg_key_ID): Derive key ID from signed release tag.
+	With this change, we can all remove the gpg_key_ID = ... definition
+	from our respective cfg.mk files.
+
 	maint.mk: create announcement template in ~/, not in /tmp
 	* top/maint.mk (emit_upload_commands): Adjust.
 	(release-prep): Emit into ~/announce-..., not /tmp/announce-...
diff --git a/top/maint.mk b/top/maint.mk
--- a/top/maint.mk
+++ b/top/maint.mk
@@ -30,7 +30,6 @@
   $(shell gzip --help 2>/dev/null|grep rsyncable >/dev/null && echo --rsyncable)
 GZIP_ENV = '--no-name --best $(gzip_rsyncable)'
 
-# cfg.mk must define the gpg_key_ID used by this package.
 GIT = git
 VC = $(GIT)
 VC-tag = git tag -s -m '$(VERSION)' -u '$(gpg_key_ID)'
@@ -688,6 +687,13 @@
 gnulib-version = $$(cd $(gnulib_dir) && git describe)
 bootstrap-tools ?= autoconf,automake,gnulib
 
+# If it's not already specified, derive the GPG key ID from
+# the signed tag we've just applied to mark this release.
+gpg_key_ID ?= \
+  $$(git cat-file tag v$(VERSION) > .ann-sig \
+     && gpgv .ann-sig - < /dev/null 2>&1 \
+	  | sed -n '/.*key ID \([0-9A-F]*\)/s//\1/p'; rm -f .ann-sig)
+
 announcement: NEWS ChangeLog $(rel-files)
 	@$(build_aux)/announce-gen					\
 	    --release-type=$(RELEASE_TYPE)				\