[master] add branchsync to util

Script to sync release branch to subscription branch.

util/branchsync.sh

+#!/bin/sh
+# branchsync:
+# pull in changes from a main BIND 9 release branch to a subscription
+# branch (e.g., from v9_9 to v9_9_sub).  This excludes commits from the
+# 'tinderbox' user (copyright updates and doc regeneration) because those
+# will be taken care of in the subscription branch itself.
+#
+# Most of the time, changes in the main branch will cherry-pick cleanly
+# into the subscription branch. When one fails, we reset to the last
+# commit that went cleanly, and send mail -- or, if running in interactive
+# mode, we stop and allow the user to resolve conflicts.
+#
+# Usage:
+# branchsync.sh [ -i ] [ -c ]
+#   -i: interactive mode (don't reset and send mail)
+#   -c: continue (conflicts are resolved; edit message and commit)
+
+savehash () {
+    cat <<EOF > $1.new
+SOURCEBRANCH=$2
+LASTHASH=$3
+EOF
+    mv -f $1.new $1
+    git add branchsync.dat
+}
+
+thisbranch () {
+    git branch | grep '^\*' | cut -b3-
+}
+
+docommit () {
+    git log -1 --pretty=format:%s%n%b $2 > orig_commit_msg.tmp
+    firstline=`head -1 orig_commit_msg.tmp | sed 's/^\[[a-z0-9_]*\] //'`
+    tail -n +2 orig_commit_msg.tmp > remainder.tmp
+    firstline="[$BRANCH] $firstline"
+    echo $firstline > commit_msg.tmp
+    cat remainder.tmp >> commit_msg.tmp
+    echo "pulled from $1 by script." >> commit_msg.tmp
+    echo "hash: $2" >> commit_msg.tmp
+    msg=`cat commit_msg.tmp`
+    rm -f orig_commit_msg.tmp commit_msg.tmp remainder.tmp
+    git commit --no-verify --no-edit -m "$msg" || exit 1
+}
+
+BRANCH=`thisbranch`
+. branchsync.dat
+
+# check arguments
+interactive=
+continuing=
+case $1 in
+    '-i') interactive=yes
+          ;;
+    '-c') docommit $SOURCEBRANCH $LASTHASH
+          interactive=yes
+          continuing=yes
+          ;;
+    *)    if [ $# -ne 0 ]; then
+             echo "Usage: $0 [ -i ] [ -c ]" 1>&2
+             exit 1
+          fi
+          ;;
+esac
+
+if [ -z "$continuing" ]; then
+    status=`git status -suno`
+    if [ -n "$status" ]; then
+         echo "Work tree is not clean. Clean up, or run with -c:"
+         echo "$status"
+         exit 1
+    fi
+
+    # make sure both branches are synced to the source repository
+    git pull origin $BRANCH
+    git checkout -f $SOURCEBRANCH
+    git pull origin $SOURCEBRANCH
+    git checkout -f $BRANCH
+fi
+
+# loop through commits looking for ones that should be cherry-picked
+git log $SOURCEBRANCH --reverse --format='%H %aN' $LASTHASH..$SOURCEBRANCH | \
+  grep -v Tinderbox | cut -d' ' -f1 | {
+    while read hash; do
+        if git cherry-pick -xn ${hash}; then
+            # cherry-pick was clean
+            # restore the copyrights file
+            git checkout HEAD -- util/copyrights
+            # note which hash we've merged
+            savehash branchsync.dat $SOURCEBRANCH $hash
+
+            # fix the commit message, and commit
+            docommit $SOURCEBRANCH $hash
+
+            # move on to the next commit
+            continue
+        elif [ -n "$interactive" ]; then
+            # interactive mode -- wait for user to fix things
+            git checkout HEAD -- util/copyrights
+            # note which hash we've merged
+            savehash branchsync.dat $SOURCEBRANCH $hash
+        else
+            # noninteractive mode
+            # reset everything
+            git reset --hard
+
+            # build mail message
+            MESSAGE="Attempt to cherry pick ${hash}\nto $BRANCH failed."
+            MESSAGE=$MESSAGE"\nCommit message of change was:\n"
+            MESSAGE=$MESSAGE"`git log -1 --pretty=format:%s%n%b ${hash}`"
+            subject="Branch sync to $BRANCH failed"
+
+            # send mail
+            echo "$MESSAGE" | mail -s "$subject" bind-changes
+        fi
+
+        break
+    done
+}

util/kit.sh

@@ -158,6 +158,9 @@ find util -depth -type d -print | xargs rmdir 2>/dev/null
 # Remove all .gitignore files
 find . -name .gitignore -print | xargs rm
 
+# Remove branchsync.dat, if present
+rm -f branchsync.dat
+
 # populate srcid file
 echo "SRCID=$shorthash" > srcid