push_new_series.sh

#!/usr/bin/env bash

set -euo pipefail

die()
{
    echo 1>&2 "$@"
    exit 1
}

# return URL for mailboxes for previous, current and next month. This way, we
# don't miss any email, even with different timezones.
mailbox_archives()
{
    current_date=$1

    current_month=$(date +%m --date "$current_date")
    current_year=$(date +%Y --date "$current_date")

    if [ $current_month == "01" ]; then
        previous_month=12
        previous_year=$((current_year - 1))
    elif [ $current_month == "12" ]; then
        next_month=01
        next_year=$((current_year + 1))
    else
        previous_year=$current_year
        next_year=$current_year
        previous_month=$(printf "%02d" $((current_month - 1)))
        next_month=$(printf "%02d" $((current_month + 1)))
    fi

    qemu_archive="https://lists.gnu.org/archive/mbox/qemu-devel/"
    echo $qemu_archive$previous_year-$previous_month \
         $qemu_archive$current_year-$current_month \
         $qemu_archive$next_year-$next_month
}

# download all emails for previous, current and next month.
fetch_mails()
{
    out=$1
    rm -rf $out
    mkdir -p $out
    mkdir -p $out.mailbox
    pushd $out.mailbox
    archives=$(mailbox_archives "$(date)")
    # we can have missing current or next mailbox
    wget --no-clobber $archives || true
    popd
    git mailsplit -o$out $out.mailbox/*
}

find_series()
{
    mail_dir=$1
    # find all message id, for mails without a reference (i.e. first in series).
    # we reverse sort to bring newest series first.
    grep -Lri '^References:' $mail_dir | sort -r | while read m
    do
        msg_id=$(grep -i '^message-id: ' $m | head -n1 | sed -e 's/.*<//' -e 's/>$//')
        date=$(grep -i '^date: ' $m | head -n1 | sed -e 's/^date: //I')
        echo "$msg_id|$date"
    done
}

git remote remove upstream || true
git remote add upstream -f https://gitlab.com/qemu-project/qemu

fetch_mails mails
find_series mails | while read s
do
    msg_id=$(echo "$s" | cut -f 1 -d '|')
    date=$(echo "$s" | cut -f 2 -d '|')
    echo $msg_id
    echo $date
    base_git_revision=$(git log -n1 --format=format:%H --before="$date" --first-parent upstream/master)
    echo $base_git_revision

    git checkout "$base_git_revision"
    git branch -D $msg_id || true
    if git checkout -b $msg_id; then
        if ! b4 shazam $msg_id |& tee apply.log; then
            git am --abort
            git add apply.log
            git commit -m 'am failed'
        fi
        git push --set-upstream origin $msg_id
    fi
done