commit-hook: tweak add_ChangeId() to tolerate git-am -s behavior

git-am -s add systematically an empty line before adding the
signoff line, which interfere with gerrit's rule that
the ChangeID must be in the last paragraph

This patch address that be remoming an existing Change-Id from
the commit message and re-insterting it at the 'proper' place

Change-Id: I I742b17031c6e3da4f9d94dcb0579bce8c496d41d
Signed-off-by: Norbert Thiebaud <nthiebaud@gmail.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/git-hooks/commit-msg b/git-hooks/commit-msg
index f8df4e2075f4..d784d6561130 100755
--- a/git-hooks/commit-msg
+++ b/git-hooks/commit-msg
@@ -100,12 +100,14 @@ add_ChangeId() {
                 return
         fi
 
-        if grep -i '^Change-Id:' "$MSG" >/dev/null
+        id=`grep -i '^Change-Id:' "$MSG" | sed -e "s/.*://"`
+        temp_msg=`grep -v -i '^Change-Id:' "$MSG"`
+        echo "$temp_msg" > "$MSG"
+
+        if  test -z "$id"
         then
-                return
+            id=`_gen_ChangeId`
         fi
-
-        id=`_gen_ChangeId`
         perl -e '
                 $MSG = shift;
                 $id = shift;