dim

#!/bin/bash
#
# dim - drm inglorious maintainer script
#
# Copyright © 2012-2018 Intel Corporation
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice (including the next
# paragraph) shall be included in all copies or substantial portions of the
# Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
# IN THE SOFTWARE.
#
# Authors:
#    Daniel Vetter <daniel.vetter@ffwll.ch>
#    Jani Nikula <jani.nikula@intel.com>

# fail on any goof-up
set -e

#
# User configuration. Global DIM_ prefixed uppercase variables. Set in
# environment or configuration file. See dimrc.sample for an example.
#

# dim configuration file
DIM_CONFIG=${DIM_CONFIG:-$HOME/.dimrc}
if [ -r $DIM_CONFIG ]; then
	# shellcheck source=/dev/null
	. $DIM_CONFIG
fi

# prefix for repo directories
DIM_PREFIX=${DIM_PREFIX:-$HOME/linux}

# main maintainer repo under $DIM_PREFIX
DIM_REPO=${DIM_REPO:-${DIM_DRM_INTEL:-src}}

# mail user agent. must support a subset of mutt(1) command line options:
# usage: $DIM_MUA [-s subject] [-i file] [-c cc-addr] to-addr [...]
DIM_MUA=${DIM_MUA:-mutt}

# make options (not used for C=1)
DIM_MAKE_OPTIONS=${DIM_MAKE_OPTIONS:--j20}

# command to run after dim apply
DIM_POST_APPLY_ACTION=${DIM_POST_APPLY_ACTION:-}

# greetings pull request template
DIM_TEMPLATE_HELLO=${DIM_TEMPLATE_HELLO:-$HOME/.dim.template.hello}

# signature pull request template
DIM_TEMPLATE_SIGNATURE=${DIM_TEMPLATE_SIGNATURE:-$HOME/.dim.template.signature}

# GPG key id for signing tags. If unset, don't sign.
DIM_GPG_KEYID=${DIM_GPG_KEYID:+-u $DIM_GPG_KEYID}

#
# Internal configuration. Global dim_ prefixed variables.
#

dim=$(basename $0)

dim_today=$(date +%Y-%m-%d)
dim_timestamp="$(date --utc +%Yy-%mm-%dd-%Hh-%Mm-%Ss) UTC"

maintainer_tools_https=https://gitlab.freedesktop.org/drm/maintainer-tools.git

# Recipients for all dim based pull requests.
# Add To: lines to the end, Cc: lines in the beginning with -c.
dim_pull_request_recipients=(
	-c "Jani Nikula <jani.nikula@linux.intel.com>"
	-c "Joonas Lahtinen <joonas.lahtinen@linux.intel.com>"
	-c "Rodrigo Vivi <rodrigo.vivi@intel.com>"
	-c "Sean Paul <sean@poorly.run>"
	-c "Maarten Lankhorst <maarten.lankhorst@linux.intel.com>"
	-c "Maxime Ripard <maxime.ripard@bootlin.com>"
	-c "dri-devel@lists.freedesktop.org"
	-c "intel-gfx@lists.freedesktop.org"
	-c "dim-tools@lists.freedesktop.org"
	"Dave Airlie <airlied@gmail.com>"
	"Daniel Vetter <daniel.vetter@ffwll.ch>"
)

# integration configuration
dim_integration_config=nightly.conf

#
# Only function and alias definitions until the command line argument parsing
# and subcommand handling at the end.
#

function read_integration_config
{
	# clear everything first to allow configuration reload
	unset drm_tip_repos drm_tip_config
	declare -g -A drm_tip_repos
	declare -g -a drm_tip_config

	if [ -r $DIM_PREFIX/drm-rerere/$dim_integration_config ]; then
		# shellcheck source=/dev/null
		source $DIM_PREFIX/drm-rerere/$dim_integration_config

		if [[ "${#drm_tip_repos[@]}" = "0" ]] || [[ "${#drm_tip_config[@]}" = "0" ]]; then
			echoerr "$dim_integration_config not set up correctly, please fix manually"
			exit 1
		fi
	else
		echoerr "$dim_integration_config is missing, please check your configuration and/or run dim setup"
		exit 1
	fi

	dim_branches=
	for conf in "${drm_tip_config[@]}"; do
		local repo branch override
		read -r repo branch override <<< $conf
		if [[ "$repo" = "drm-intel" || "$repo" = "drm-misc" ]]; then
			dim_branches="$dim_branches $branch"
		fi
	done
}

function echoerr
{
	echo "$dim: $*" >&2
}

function warn_or_fail
{
	if [[ $FORCE ]] ; then
		echoerr "WARNING: $1, but continuing"
	elif [[ $DRY ]] ; then
		echoerr "WARNING: $1, but continuing dry-run"
	else
		echoerr "ERROR: $1, aborting"
		exit 1
	fi
}

function pause
{
	read -rsp "Press any key to continue..." -n1 key2
	echo
}

function ask_user
{
	local prompt="$@ (y/N) "

	read -n 1 -rsp "$prompt"
	echo
	if [[ $REPLY =~ ^[Yy]$ ]]; then
		return 0
	else
		return 1
	fi
}

#
# Variable naming convetion:
#
# repo:
#	symbolic git repository name from $dim_integration_config
# remote:
#	local remote name in the git repository for the current path
# branch:
#	git branch name - dim assumes that the remote and local name match
# url:
#	url to a repo, using ssh:// protocol
# git_url:
#	url to a repo, but using anonymous git:// protocol
#
# The below functions map between these.
#

function url_to_remote # url [url ...]
{
	local url remote

	if [[ "$#" = "0" ]]; then
		echoerr "url_to_remote without URLs"
		return 1
	fi

	for url; do
		remote=$(git remote -v | grep -m 1 "$url/\? (" | cut -f 1)
		if [[ -n "$remote" ]]; then
			echo "$remote"
			return 0
		fi
	done

	echoerr "No git remote for any of the URLs $* found in $(pwd)"

	url=$1
	remote=${url%.git}
	remote=${remote##*/}
	read -r -i "$remote" -e -p "Enter a name to auto-add this remote, leave blank to abort: " remote
	if [[ -z "$remote" ]]; then
		echoerr "Please set it up yourself using:"
		echoerr "    $ git remote add <name> $url"
		echoerr "with a name of your choice."
		return 1
	fi

	git remote add $remote $url

	echo $remote

	return 0
}

function pick_protocol_url # (git|ssh|https|whatever) url [url ...]
{
	local url protocol protocol_url

	if [[ "$#" -lt "2" ]]; then
		echoerr "pick_protocol_url without protocol or URLs"
		return 1
	fi

	protocol=$1
	shift

	# Find the URL that has given protocol
	for url; do
		case $url in
			${protocol}://*)
				protocol_url=$url
				break
				;;
		esac
	done

	if [[ -z "$protocol_url" ]]; then
		echoerr "No $protocol URL in any of the URLs: $*"
		return 1
	fi

	echo $protocol_url
}

function branch_to_remote # branch
{
	local branch remote repo

	branch=$1
	repo=$(branch_to_repo $branch)

	if [[ -z "$repo" ]] ; then
		# fallback for special branches like rerere-cache
		remote=$(git rev-parse --abbrev-ref --symbolic-full-name "$branch@{upstream}")
		remote=${remote%%/*}
	else
		remote=$(repo_to_remote $repo)
	fi

	echo $remote
}

function repo_to_remote # repo
{
	local repo url_list

	repo=$1
	url_list=${drm_tip_repos[$repo]}

	if [[ -z "$url_list" ]]; then
		echoerr "unknown repo $repo"
		return 1
	fi

	url_to_remote $url_list
}

function branch_to_repo # branch
{
	for conf in "${drm_tip_config[@]}"; do
		local repo branch override
		read -r repo branch override <<< $conf

		if [[ "$branch" == "$1" ]] ; then
			echo $repo
		fi
	done

	echo ""
}

function dim_uptodate
{
	local using

	using="${BASH_SOURCE[0]}"

	if [[ ! -e "$using" ]]; then
		echoerr "could not figure out the version being used ($using)."
		return 1
	fi

	if [[ ! -e "$DIM_PREFIX/maintainer-tools/.git" ]]; then
		echoerr "could not find the upstream repo for $dim."
		return 1
	fi

	git --git-dir=$DIM_PREFIX/maintainer-tools/.git fetch -q

	if ! git --git-dir=$DIM_PREFIX/maintainer-tools/.git show "@{upstream}:dim" |\
			diff "$using" - >& /dev/null; then
		echoerr "not running upstream version of the script."
		return 1
	fi
}

function git_fetch_helper # remote
{
	local remote

	remote=$1

	if ! git fetch --prune -q $remote ; then
		# old git versions returned 128 if there was nothing to fetch
		if [[ $? -ne "128" ]] ; then
			echoerr "Failed to fetch $remote"
			return 1
		fi
	fi
}

function git_current_branch
{
	git symbolic-ref -q --short HEAD
}

function git_is_current_branch # branch
{
	test "$(git_current_branch)" = "$1"
}

function git_branch_exists # branch
{
	if [[ "$(git branch --list $1)" == "" ]] ; then
		false
	else
		true
	fi
}

# $1: branch
# $2: upstream
function git_unmerged_tags
{
	local branch upstream

	branch=$1
	upstream=$2

	# assume branch based tag names, ensure space separated list
	git log --decorate --pretty=%D "$branch@{upstream}" ^$upstream |\
		grep -o "tag: $branch-[0-9-]\+" |\
		sed -e "s/^tag: //" |\
		tr "\n" " "
}

function git_committer_email
{
	if ! committer_email=$(git config --get user.email) ; then
		committer_email=${EMAIL-}
	fi

	echo $committer_email
}

function check_for_updates
{
	local stamp stampfile

	stampfile=$HOME/.dim-update-check-timestamp

	# daily check for updates based on file timestamp
	stamp=$(stat --printf=%Y $stampfile 2>/dev/null || echo -n 0)
	if [[ $((stamp + 24*60*60)) -lt $(date +%s) ]]; then
		dim_uptodate || true
		touch $stampfile
	fi
}

function check_git_version
{
	local min_version="git version 2.8"

	if ! echo -e "$min_version\n$(git version)" | sort -VC; then
		echoerr "WARNING: recommended minimum $min_version, you have $(git version)"
	fi
}

function check_dim_config
{
	if [[ "$DIM_REPO" == "drm-tip" || "$DIM_REPO" == "drm-rerere" || "$DIM_REPO" == "maintainer-tools" ]];  then
		echoerr "WARNING: setting $DIM_REPO for DIM_REPO not allowed"
		exit 1
	fi
}

# get message id from file
# $1 = file
message_get_id ()
{
	python <<EOF
from email.parser import Parser
headers = Parser().parse(open('$1', 'r'))
message_id = headers['message-id']
if message_id is not None:
    print(message_id.strip('<>'))
EOF
}

message_print_body ()
{
	python2 <<EOF
import email

def print_part(part):
    mtype = part.get_content_maintype()
    if mtype == 'text':
        print(part.get_payload(decode=True))

def print_msg(file):
    msg = email.message_from_file(file)
    if msg.is_multipart():
        for part in msg.get_payload():
            print_part(part)
    else:
        print_part(msg)

print_msg(open('$1', 'r'))
EOF
}

# append all arguments as tags at the end of the commit message of HEAD
function dim_commit_add_tag
{
	for arg; do
		# the first sed deletes all trailing blank lines at the end
		git log -1 --pretty=%B | \
			sed -e :a -e '/^\n*$/{$d;N;ba' -e '}' | \
			sed "\$a${arg}" | \
			git commit --amend -F-
	done
}

# $1: branch [optional]
function git_find_tip
{
	git log $1 -1 --format=%H --grep="^drm-tip: .* integration manifest$"
}

# $1: branch [optional]
function dim_retip
{
	local branch upstream new_upstream

	branch="$1"

	if [ -n "$branch" ] ; then
		shift
	else
		branch=$(git symbolic-ref --short HEAD)
	fi

	if repo_to_remote drm-tip &> /dev/null ; then
		new_upstream=$(repo_to_remote drm-tip)/drm-tip
	else
		new_upstream=$(git branch -r | grep '\/drm-tip$')
	fi
	upstream=$(git_find_tip "$branch")

	if [[ -z "$upstream" ]]; then
		echoerr "$branch is not based on drm-tip"
		return 1
	fi

	git rebase --onto $new_upstream $upstream $branch "$@"
}

function dim_range_diff
{
	local branch

	branch=${1:-@\{1\}}

	if [[ $(git rev-parse $branch | wc -l) -eq 1 ]] ; then
		if [[ $(git rev-parse $branch) == "$branch" ]] ; then
			branch="@{1}"
		else
			shift || true
		fi
		git range-diff $branch...HEAD "$@"
	else
		git range-diff "$@"
	fi
}

# update for-linux-next and for-linux-next-fixes branches
function update_linux_next # branch next next-fixes fixes
{
	local branch linux_next linux_next_fixes linux_fixes repo remote

	cd $DIM_PREFIX/drm-tip
	branch=$1
	linux_next=$2
	linux_next_fixes=$3
	linux_fixes=$4

	repo=$(branch_to_repo $branch)

	if [[ $repo != $(branch_to_repo $linux_next) ]] ; then
		return
	fi

	remote=$(repo_to_remote $repo)

	git_fetch_helper $remote

	# always update drm-intel-fixes
	echo -n "Pushing $linux_fixes to for-linux-next-fixes... "
	git push $DRY_RUN $remote +$remote/$linux_fixes:for-linux-next-fixes # >& /dev/null
	echo "Done."

	if git merge-base --is-ancestor $remote/$linux_next_fixes $remote/$linux_fixes ; then
		# -fixes has caught up to dinf, i.e. we're out of the merge
		# window. Push the next queue.
		echo -n "Out of merge window. Pushing $linux_next to for-linux-next... "
		git push $DRY_RUN $remote +$remote/$linux_next:for-linux-next >& /dev/null
		echo "Done."
	else
		# dinf is ahead of -fixes, i.e. drm-next has already closed for
		# the next merge window and we've started to gather new fixes
		# for the current -next cycle. Push dinf

		echo -n "Pushing $linux_next_fixes to for-linux-next... "
		git push $DRY_RUN $remote +$remote/$linux_next_fixes:for-linux-next >& /dev/null
		echo "Done."
	fi
}

function check_conflicts # tree
{
	if git diff | grep -q '\(<<<<<<<\|=======\|>>>>>>>\||||||||\)' ; then
		# we need an empty line to make it look pretty
		echoerr ""
		echoerr "FAILURE: Could not merge $1"
		return 1
	fi
	true
}

function git_dir
{
	git -C ${1:-$PWD} rev-parse --absolute-git-dir
}

function pull_rerere_cache
{
	cd $DIM_PREFIX/drm-rerere/
	if ! git_is_current_branch rerere-cache; then
		echo "Fail: Branch setup for the rerere-cache is borked."
		exit 1
	fi

	if ! git pull -q ; then
		# We raced with someone else hitting the same conflict, or the
		# erratic git gc for rr-cache entries nuke a few entries we
		# still want to keep. Clean up and try, but only when the
		# initial pull fails since otherwise there's no way to keep new
		# resolutions around.
		echo "Conflict in the rr-cache, cleaning up"
		git clean -fdx rr-cache/
		git checkout -f ':(glob)rr-cache/**'

		if ! git pull -q ; then
			echoerr "Failed to update the rerere cache."
			echoerr "Please manually run"
			echoerr "	$ cd $DIM_PREFIX/drm-rerere ; git pull"
			echoerr "and fixup any issues."

			return 1
		fi
	fi
	cd - > /dev/null
}

function update_rerere_cache
{
	local rr_cache_dir

	echo -n "Updating rerere cache... "

	pull_rerere_cache

	cd $DIM_PREFIX/drm-tip/

	rr_cache_dir=$(git rev-parse --git-common-dir)/rr-cache

	if [ ! -L $rr_cache_dir ] ; then
		if [ -d $rr_cache_dir ] ; then
			rm -Rf $rr_cache_dir
		fi
		ln -s "$DIM_PREFIX/drm-rerere/rr-cache" $rr_cache_dir
	fi

	cd ~-

	echo "Done."
}

function commit_rerere_cache
{
	local remote file commit_message

	echo -n "Finalizing rerere cache... "

	cd $DIM_PREFIX/drm-rerere/
	remote=$(branch_to_remote rerere-cache)

	pull_rerere_cache

	git add ./*.patch >& /dev/null || true
	git add fixups/*.patch >& /dev/null || true
	for file  in $(git ls-files -- rr-cache); do
		if ! git log --since="60 days ago" --name-only -- $file | grep $file &> /dev/null; then
			git rm $file &> /dev/null || true
		fi
	done
	find rr-cache/ -mtime -1 -type f -not -name "thisimage*" -print0 | xargs -0 git add > /dev/null || true
	git rm rr-cache/rr-cache &> /dev/null || true

	commit_message=$(mktemp)
	cat > $commit_message <<-EOF
		$dim_timestamp: $integration_branch rerere cache update

		$(git --version)
		EOF

	if git commit -F $commit_message >& /dev/null; then
		echo -n "New commit. "
	else
		echo -n "Nothing changed. "
	fi
	rm $commit_message

	echo -n "Pushing rerere cache... "
	git push $DRY_RUN $remote HEAD >& /dev/null && echo "Done."
}

function fetch_all
{
	for repo in "${!drm_tip_repos[@]}"; do
		remote=$(repo_to_remote $repo)
		if [[ "$repo" = "$remote" ]]; then
			echo -n "Fetching $repo... "
		else
			echo -n "Fetching $repo (local remote $remote)... "
		fi
		git_fetch_helper $remote
		echo "Done."
	done
}

function find_fixup_file # repo branch
{
	local file_paths repo branch rerere
	repo=$1
	branch=$2
	rerere=$DIM_PREFIX/drm-rerere

	file_paths="$rerere/${repo}-${branch//\//-}-fixup.patch
	            $rerere/fixups/${branch//\//-}.patch"

	for file_path in $file_paths; do
		[ -f "$file_path" ] && break
	done

	echo "$file_path"
}

function dim_rebuild_tip
{
	local integration_branch specfile first rerere repo remote

	integration_branch=drm-tip
	specfile=$(mktemp)
	first=1

	rerere=$DIM_PREFIX/drm-rerere

	cd $rerere
	if git status --porcelain | grep -v "^.. rr-cache" | grep -q -v "^[ ?][ ?]"; then
		warn_or_fail "integration configuration file $dim_integration_config not committed"
	fi

	update_rerere_cache

	echo -n "Reloading $dim_integration_config... "
	read_integration_config
	echo "Done."

	cd $DIM_PREFIX/$integration_branch
	if ! git_is_current_branch $integration_branch ; then
		echo "Branch setup for the integration repo is borked"
		exit 1
	fi

	# rerere uses sha1 of the diff to identify conflicts, we must ensure
	# that they look the same for everyone
	git config merge.conflictstyle merge

	fetch_all

	# merge -fixes
	for conf in "${drm_tip_config[@]}"; do
		local branch override sha1 fixup_file

		read -r repo branch override <<< $conf
		remote=$(repo_to_remote $repo)
		sha1=$remote/$branch

		if [[ "$repo" = "$remote" ]]; then
			echo -n "Merging $repo/$branch... "
		else
			echo -n "Merging $repo/$branch (local remote $remote)... "
		fi

		if [[ -n "$override" ]]; then
			sha1=$override
			echo -n "Using override sha1: $sha1... "
		fi

		if [ $first == 1 ] ; then
			git reset --hard $sha1 &> /dev/null
			echo "Reset. Done."
			first=0
		elif git merge --rerere-autoupdate --ff-only $sha1 >& /dev/null ; then
			# nothing to do if just fast-forward
			echo "Fast-forward. Done."
			true
		else
			fixup_file=$(find_fixup_file $repo $branch)
			echo $branch > .fixup_branch

			git merge --rerere-autoupdate --no-commit $sha1 >& /dev/null || true
			# normalize conflict markers
			if git grep -l '^>>>>>>> ' &> /dev/null ; then
				git grep -l '^>>>>>>> ' | xargs sed -e "s|^>>>>>>> .*$|>>>>>>> $repo\/$branch|" -i
			fi

			if [ -f $fixup_file ] ; then
				echo -n "Applying manual fixup patch for $integration_branch merge... "
				patch -p1 -i $fixup_file
			fi
			if ! check_conflicts "$repo/$branch" ; then
				echoerr "See the section \"Resolving Conflicts when Rebuilding drm-tip\""
				echoerr "in the drm-tip.rst documentation for how to handle this situation."
				return 1
			fi
			git add -u

			# because we filter out fast-forward merges there will
			# always be something to commit
			git commit --no-edit --quiet
			echo "Done."
		fi

		echo -e "$repo $branch $(git rev-parse $sha1)\n\t$(git log -1 $sha1 --pretty=format:%s)" >> $specfile

		$INTERACTIVE
	done

	echo -n "Adding integration manifest $integration_branch: $dim_timestamp... "
	mv $specfile integration-manifest
	git add integration-manifest
	git commit --quiet -m "$integration_branch: $dim_timestamp integration manifest"
	echo "Done."

	remote=$(repo_to_remote drm-tip)

	echo -n "Pushing $integration_branch... "
	git push $DRY_RUN $remote +HEAD >& /dev/null && echo "Done."

	commit_rerere_cache
}

# additional patch checks before pushing, e.g. for r-b tags
function checkpatch_commit_push
{
	local sha1 managed_branch rv author committer author_outlook cite

	sha1=$1
	managed_branch=$2
	rv=0

	cite=$(dim_cite $sha1)

	# use real names for people with many different email addresses
	author=$(git show -s $sha1 --format="format:%an")
	committer=$(git show -s $sha1 --format="format:%cn")
	# outlook mangles mails into "Last, First"
	author_outlook=$(git show -s $sha1 --format="format:%an" | sed -e 's/\([^ ]*\) \(.*\)/\2, \1/')

	# check for author sign-off
	if ! git show -s $sha1 | grep -qi "Signed-off-by:.*\\($author\\|$author_outlook\\)" ; then
		echoerr "$cite: author Signed-off-by missing."
		rv=1
	fi

	# check for committer sign-off
	if ! git show -s $sha1 | grep -qi "Signed-off-by:.*$committer"  ; then
		echoerr "$cite: committer Signed-off-by missing."
		rv=1
	fi

	# check for Link tag
	if [[ "$managed_branch" = "1" ]] && ! git show -s $sha1 | grep -qi 'Link:'  ; then
		echoerr "$cite: Link tag missing."
		rv=1
	fi

	# check for a-b/r-b tag
	if ! git show -s $sha1 | grep -qi '\(reviewed\|acked\)\S*-by:' && \
	   ! [[ "$committer" != "$author" ]]; then
		echoerr "$cite: mandatory review missing."
		rv=1
	fi

	return $rv
}

function checkmerge_commit_push
{
	local sha1 managed_branch rv body_text cite

	sha1=$1
	managed_branch=${2}
	rv=0

	cite=$(dim_cite $sha1)

	body_text="$(git show $sha1 -s --format="format:%b" | grep -v "^$" | grep -v "^\S*:")"

	if [[ -z "$body_text" ]] ; then
		echoerr "$cite: merge commit justification missing."
		rv=1
	fi

	return $rv
}

function checkpatch_commit_push_range
{
	local rv managed_branch

	managed_branch=$1
	shift
	rv=0

	for sha1 in $(git rev-list "$@" --no-merges) ; do
		checkpatch_commit_push $sha1 $managed_branch || rv=1
	done

	for sha1 in $(git rev-list "$@" --merges) ; do
		checkmerge_commit_push $sha1 $managed_branch || rv=1
	done

	if [ $rv == "1" ] ; then
		warn_or_fail "issues in commits detected"
	fi
}

# push branch $1, rebuild drm-tip. the rest of the arguments are passed to git
# push.
function dim_push_branch
{
	local branch remote committer_email count

	branch=${1:?$usage}
	shift

	assert_branch $branch

	remote=$(branch_to_remote $branch)

	committer_email=$(git_committer_email)

	checkpatch_commit_push_range 1 "$branch@{u}..$branch" --first-parent --committer="$committer_email"

	# Apart from maintainers pushing merges or rebases, most patches should
	# be pushed in small batches.
	count=$(git rev-list --count --first-parent "$branch@{u}..$branch")
	if [[ $count -gt 10 ]]; then
		if ! ask_user "Pushing $count commits. Are you sure?"; then
			echoerr "NOTE: Branch not pushed."
			return 1
		fi
	fi

	git push $DRY_RUN $remote $branch "$@"

	update_linux_next $branch drm-intel-next-queued drm-intel-next-fixes drm-intel-fixes
	update_linux_next $branch drm-misc-next drm-misc-next-fixes drm-misc-fixes
	update_linux_next $branch drm-amd-next drm-amd-next-fixes drm-amd-fixes

	dim_rebuild_tip
}

dim_alias_pq=push-queued
function dim_push_queued
{
	dim_push_branch drm-intel-next-queued "$@"
}

dim_alias_pnf=push-next-fixes
function dim_push_next_fixes
{
	dim_push_branch drm-intel-next-fixes "$@"
}

dim_alias_pf=push-fixes
function dim_push_fixes
{
	dim_push_branch drm-intel-fixes "$@"
}

function dim_push
{
	dim_push_branch $(git_current_branch) "$@"
}

function apply_patch #patch_file
{
	local patch message_id committer_email patch_from sob rv

	patch="$1"
	shift
	message_id=$(message_get_id $patch)
	committer_email=$(git_committer_email)

	patch_from=$(grep "From:" "$patch" | head -1)
	if [[ "$patch_from" != *"$committer_email"* ]] ; then
		sob=-s
	fi

	if ! git am --scissors -3 $sob "$@" $patch ; then
		echoerr "ERROR: git apply-mbox failed"
		return 1
	fi

	if [ -n "$message_id" ]; then
		dim_commit_add_tag "Link: https://patchwork.freedesktop.org/patch/msgid/$message_id"
	else
		echoerr "WARNING: No message-id found in the patch file."
		rv=1
	fi

	if ! checkpatch_commit HEAD branch; then
		rv=1
	fi
	if ! check_maintainer $branch HEAD; then
		rv=1
	fi

	eval $DRY $DIM_POST_APPLY_ACTION
	return $rv
}

# ensure we're on branch $1, and apply patches. the rest of the arguments are
# passed to git am.
dim_alias_ab=apply-branch
dim_alias_sob=apply-branch
function dim_apply_branch
{
	local branch file rv

	branch=${1:?$usage}
	shift
	file=$(mktemp)
	dir=$(mktemp -d)

	assert_branch $branch
	assert_repo_clean

	cat > $file
	git mailsplit -b -o$dir $file > /dev/null

	for patch in "$dir"/*; do
		if ! apply_patch $patch "$@"; then
			rv=1
		fi
	done
	rm -rf $file $dir

	return $rv
}

function dim_apply_pull
{
	local branch file message_id pull_branch rv merge_msg_file from_line

	branch=${1:?$usage}
	file=$(mktemp)

	assert_branch $branch
	assert_repo_clean

	cat > $file

	pull_branch=$(message_print_body "$file" | sed -ne '/[gG]it repository at:$/{n;n;p}')
	from_line=$(grep '^From:' $file)

	if [[ -z "$pull_branch" ]] ; then
		echoerr "no pull request found"
		return 1
	fi

	message_id=$(message_get_id $file)
	if [ -z "$message_id" ]; then
		warn_or_fail "No message-id found in the pull request file."
	fi

	echo Pulling $pull_branch ...

	git fetch $pull_branch
	if [[ -z "$(git rev-list HEAD..FETCH_HEAD)" ]] ; then
		warn_or_fail "Nothing in the pull request"
	fi

	checkpatch_commit_push_range 0 "HEAD..FETCH_HEAD"

	if ! $DRY git pull --no-ff $pull_branch ; then
		if ! check_conflicts "$pull_branch" ; then
			echoerr "Please resolve and then commit normally using git"

			merge_msg_file="$(git_dir)/MERGE_MSG"
			if [ -n "$message_id" ]; then
				echo "$from_line" >> $merge_msg_file
				echo "Link: https://patchwork.freedesktop.org/patch/msgid/$message_id" >> $merge_msg_file
			fi

			return 1
		else
			$DRY git add -u
			$DRY git commit --no-edit --quiet
		fi
	fi

	$DRY git commit --amend -s --no-edit
	if [ -n "$message_id" ]; then
		$DRY dim_commit_add_tag "$from_line"
		$DRY dim_commit_add_tag "Link: https://patchwork.freedesktop.org/patch/msgid/$message_id"
	fi


	eval $DRY $DIM_POST_APPLY_ACTION

	return $rv
}

function validate_upstream_baseline
{
	local branch upstream

	branch=${1}
	upstream=${2}

	cd $DIM_PREFIX/drm-tip

	if ! dim_list_upstreams | grep -q "^$upstream\$"; then
		if ! git rev-parse --verify -q "refs/tags/$upstream" > /dev/null ; then
			warn_or_fail "$upstream is neither an upstream branch nor a tag"
		fi
	fi

	tip_remote=$(repo_to_remote drm-tip)
	git fetch -q $tip_remote || true

	if ! git merge-base --is-ancestor $upstream $tip_remote/drm-tip ; then
		echoerr "Upstream $upstream not merged into drm-tip, aborting."
		echoerr "Please make sure any backmerge is tested in drm-tip,"
		echoerr "to give all the CI bots some time to find bugs."
		exit 1
	fi

	assert_branch $branch
	assert_repo_clean
}

function dim_backmerge
{
	local branch upstream patch_file

	branch=${1:?$usage}
	upstream=${2:?$usage}

	validate_upstream_baseline $branch $upstream

	git merge --rerere-autoupdate --no-commit $upstream >& /dev/null || true

	patch_file=$(git_dir)/MERGE_MSG


	cat > $patch_file <<-HERE
		Merge $upstream into $branch

		*** DETAILED BACKMERGE RATIONALE HERE ***

		HERE

	if ! check_conflicts "$upstream" ; then
		echoerr "Conflicts found while merging $upstream into $branch."
		echoerr "This should only happen when git rerere gets confused"
		echoerr "or if there's a manual fixup patch in drm-rerere."
		echoerr "Please proceed with extreme caution."
		echoerr "Once the conflict is resolved, commit it with"
		echoerr "   git commit -a"
	fi

	git add -u
	git commit -s
}

function dim_rebase
{
	local branch upstream patch_file

	branch=${1:?$usage}
	upstream=${2:?$usage}

	validate_upstream_baseline $branch $upstream

	git rebase --signoff $upstream >& /dev/null || true
	if ! check_conflicts "$upstream" ; then
		echoerr "Conflicts found while rebasing $branch onto $upstream."
		echoerr "Please proceed with extreme caution."
		echoerr "Resolve the conflict and test it.  Once the conflict "
		echoerr "is resolved, commit it with: "
		echoerr "   git commit -a"
		echoerr "And continue the rebase with: "
		echoerr "   git rebase --continue"
		exit 1
	fi
}

function dim_add_link
{
	local branch file message_id

	branch=${1:?$usage}
	shift
	file=$(mktemp)

	assert_branch $branch
	assert_repo_clean

	cat > $file

	message_id=$(message_get_id $file)

	rm -f $file

	if [[ -n "$message_id" ]]; then
		dim_commit_add_tag "Link: https://patchwork.freedesktop.org/patch/msgid/$message_id"
	else
		echoerr "No message-id found in the patch file."
	fi
}

function dim_add_link_queued
{
	dim_add_link drm-intel-next-queued "$@"
}

function dim_add_link_fixes
{
	dim_add_link drm-intel-fixes "$@"
}

function dim_add_link_next_fixes
{
	dim_add_link drm-intel-next-fixes "$@"
}

dim_alias_aq=apply-queued
function dim_apply_queued
{
	dim_apply_branch drm-intel-next-queued "$@"
}

function dim_apply_fixes
{
	dim_apply_branch drm-intel-fixes "$@"
}

function dim_apply_next_fixes
{
	dim_apply_branch drm-intel-next-fixes "$@"
}

# apply patch to current branch, the rest of the arguments are passed to
# git am
dim_alias_am=apply
function dim_apply
{
	dim_apply_branch $(git_current_branch) "$@"
}

function commit_list_references
{
	local commit remote log

	cd $DIM_PREFIX/drm-tip
	remote=$(repo_to_remote drm-tip)
	git fetch -q $remote || true

	commit="$1"
	log=$(mktemp)

	git log --regexp-ignore-case --grep="${commit:0:8}" --oneline \
	    $commit..$remote/drm-tip > $log

	if [ "$(cat $log)" != "" ]; then
		echo "Commit ${commit:0:8} is referenced by later commits:"
		sed 's/^/\t/' < $log
	fi

	rm -f $log

	cd - >/dev/null
}

function dim_cherry_pick
{
	local commit

	commit=$(git rev-parse ${1:?$usage})

	git_fetch_helper $remote

	commit_list_references $commit

	$DRY git cherry-pick -s -x -e $commit
}

function git_list_fixes
{
	git log --reverse --format=format:%H --regexp-ignore-case \
	    --grep="^Cc:.*stable@vger\.kernel\.org" \
	    --grep="^Fixes: " \
	    "$@"
}

function cherry_pick_branch
{
	local branch log fail_log intel_remote needed have_fixes

	branch=${1:?$usage}
	log=$(mktemp)
	fail_log=$(mktemp)

	intel_remote=$(repo_to_remote drm-intel)

	# Look for commits in dinq tagged as fixes.
	for commit in $(git_list_fixes $intel_remote/$branch..$intel_remote/drm-intel-next-queued -- drivers/gpu/drm/i915); do
		echo -n "Considering $(dim_cite $commit)... "

		# Look at history for already cherry-picked fixes.
		# Note: use *local* branches to account for unpushed commits.
		git log drm-intel-fixes --format=format:%h --after=6months \
		    --grep="cherry picked .* $commit" > $log
		if [ "$(cat $log)" = "" ]; then
			git log drm-intel-next-fixes --format=format:%h --after=6months \
			    --grep="cherry picked .* $commit" > $log
		fi

		if [ "$(cat $log)" != "" ]; then
			echo "Already backported as $(tr "\n" " " < $log). OK."
			continue
		fi

		have_fixes=
		needed=
		for fixes in $(git show -s $commit | grep -i "^    Fixes: *[0-9a-fA-F]" | sed 's/^ *[Ff]ixes: *\([0-9a-fA-F]\+\).*/\1/'); do
			have_fixes=1
			fixes=$(git log -1 --format=format:%H $fixes 2>/dev/null || true)
			if [[ -z "$fixes" ]]; then
				continue
			fi

			# FIXME: see if the commit to be fixed has been
			# backported!
			echo -n "Fixes: $(dim_cite $fixes). "
			if [[ "$(git merge-base $branch $fixes)" = "$fixes" ]]; then
				needed=1
			fi
		done

		# Note: Cc: stable will overrule Fixes:
		if [[ -n "$have_fixes" && -z "$needed" ]]; then
			echo "Fixes a commit not in $branch. OK."
			continue
		fi

		echo "Try to cherry-pick."
		commit_list_references $commit
		if ! git cherry-pick -x -s $commit; then
			echo "FAILED: $(dim_cite $commit)"
			(dim_cite $commit) >> $fail_log
			git cherry-pick --abort
		fi
	done

	# FIXME: evolve this into an email report to commit authors etc.
	if [ "$(cat $fail_log)" != "" ]; then
		echo "Failed to cherry-pick:"
		cat $fail_log
	fi

	rm -f $log $fail_log
}

function dim_cherry_pick_fixes
{
	assert_branch drm-intel-fixes
	cherry_pick_branch drm-intel-fixes "$@"
}

function dim_cherry_pick_next_fixes
{
	assert_branch drm-intel-next-fixes
	cherry_pick_branch drm-intel-next-fixes "$@"
}

dim_alias_ar=apply-resolved
function dim_apply_resolved
{
	make $DIM_MAKE_OPTIONS && git add -u && git am --resolved
	checkpatch_commit HEAD || true

	eval $DRY $DIM_POST_APPLY_ACTION
}

dim_alias_mrr=magic-rebase-resolve
function dim_magic_rebase_resolve
{
	git diff HEAD | patch -p1 -R
	dim_magic_patch < $(git_dir)/rebase-merge/patch
	make $DIM_MAKE_OPTIONS
	git add -u
	git rebase --continue
}

dim_alias_mp=magic-patch
function dim_magic_patch
{
	local conflict_files

	if [[ "$1" = "-a" ]]; then
		cd $(cat ~/.dim-last-path)
	fi

	conflict_files=$(patch -p1 | grep "saving rejects" | sed -e "s/.*saving rejects to file \(.*\)/\1/")

	if [[ $conflict_files != "" ]] ; then
		echo conflicts found!
	fi

	for file in $conflict_files ; do
		echo wiggling in ${file%.rej}:
		#cat $file
		rm -f ${file%.rej}.porig
		wiggle -r ${file%.rej} $file || true
	done
}

function dim_create_branch
{
	local branch repo remote

	branch=${1:?$usage}
	start=${2:-HEAD}

	cd $DIM_PREFIX/$DIM_REPO

	repo=${branch%%/*}
	branch=${branch#*/}
	if [[ "$repo" = "$branch" ]]; then
		echoerr "give branch in format repo/branch"
		return 1
	fi

	remote=$(repo_to_remote $repo)
	if git branch -r | grep -q "$remote/$branch"; then
		echoerr "$branch already exists on $remote"
		return 1
	fi

	$DRY git branch $branch $start

	# git push gives confusing error messages for non-existing branches,
	# even with --dry-run, hence the even quieter $DRY
	$DRY git push $remote +$branch --set-upstream

	cd $DIM_PREFIX/drm-rerere
	$DRY sed -i "s/^\() # DO NOT CHANGE THIS LINE\)$/\t\"$repo\t\t${branch//\//\\\/}\"\n\1/" $dim_integration_config

	$DRY git add $dim_integration_config
	$DRY git commit --quiet -m "Add $repo $branch to $dim_integration_config"
}

function dim_remove_branch
{
	local branch repo remote

	branch=${1:?$usage}

	cd $DIM_PREFIX/$DIM_REPO

	if [[ -d $DIM_PREFIX/$branch ]] ; then
		rm -R $DIM_PREFIX/$branch
		git worktree prune &> /dev/null || true
	fi

	if git_branch_exists $branch && ! $DRY git branch -d $branch; then
		warn_or_fail "Can't remove $branch in working repo"
	fi

	cd $DIM_PREFIX/drm-tip

	repo=$(branch_to_repo $branch)

	if [[ $repo == "" ]] ; then
		echoerr "$branch not found in $dim_integration_config"
		exit 1
	fi

	remote=$(repo_to_remote $repo)

	git push $DRY_RUN $remote --delete $branch
	$DRY git fetch $remote --prune
	cd $DIM_PREFIX/drm-rerere
	$DRY sed -i "/^[[:space:]]*\"${repo}[[:space:]]\+${branch//\//\\\/}.*$/d" $dim_integration_config

	$DRY git add $dim_integration_config
	$DRY git commit --quiet -m "Remove $repo $branch from $dim_integration_config"

	dim_rebuild_tip
}

function dim_cd
{
	local path

	if [[ -d $DIM_PREFIX/$1 ]] ; then
		path=$DIM_PREFIX/$1
	else
		path=$DIM_PREFIX/$DIM_REPO
	fi

	echo $path > ~/.dim-last-path
	cd $path
}

dim_alias_co=checkout
function dim_checkout
{
	local branch repo remote

	branch=${1:?$usage}

	dim_cd $branch
	if ! git_branch_exists $branch ; then
		repo=$(branch_to_repo $branch)

		if [[ $repo == "" ]] ; then
			echoerr "$branch not found in $dim_integration_config"
			exit 1
		fi

		remote=$(repo_to_remote $repo)

		if [ "$remote" == "" ] ; then
			exit 1
		fi
		git_fetch_helper $remote
		git checkout -t $remote/$branch
	else
		git checkout $branch
	fi
}

function dim_conq
{
	dim_checkout drm-intel-next-queued "$@"
}

function dim_cof
{
	dim_checkout drm-intel-fixes "$@"
}

function dim_conf
{
	dim_checkout drm-intel-next-fixes "$@"
}

# $1 branch
# $2 commit
function check_maintainer
{
	local branch commit rv

	branch=$1
	commit=$2

        if [ "$branch" = "drm-intel-next-queued" ]; then
		if non_i915_files=$(git diff-tree --no-commit-id --name-only -r $commit | \
			grep -v "^\(drivers/gpu/drm/i915/\|include/drm/i915\|include/uapi/drm/i915\|Documentation/gpu/i915\)") && [[ -n "$non_i915_files" ]]; then
			echo -e "The following files are outside of i915 maintenance scope:\n"
			echo "$non_i915_files"
			echo -e "\nConfirm you have appropriate Acked-by and Reviewed-by for above files."
			rv=1
		fi
	fi

	return $rv
}

# $1 is the git sha1 to check
# $2 is the checkpatch profile
function checkpatch_commit
{
	local commit rv checkpatch_options profile profile_options

	commit=$1
	profile=${2:-default}

	# special branch profile maps branches to profiles
	if [[ "$profile" = "branch" ]]; then
		case "$(git_current_branch)" in
			drm-intel-next-queued|drm-intel-next-fixes|drm-intel-fixes)
				profile=drm-intel
				;;
			drm-misc-next|drm-misc-next-fixes|drm-misc-fixes)
				profile=drm-misc
				;;
			*)
				profile=default
				;;
		esac
	fi

	# map profiles to checkpatch options
	case "$profile" in
		default)
			profile_options=""
			;;
		drm-misc)
			profile_options=""
			;;
		drm-intel)
			profile_options="--max-line-length=100 --ignore=BIT_MACRO,PREFER_KERNEL_TYPES,SPLIT_STRING,LONG_LINE_STRING,BOOL_MEMBER"
			;;
		*)
			echoerr "Unknown checkpatch profile $profile"
			profile_options=""
			;;
	esac

	checkpatch_options="-q --emacs --strict --show-types $profile_options -"

	git --no-pager log --oneline -1 $commit
	if ! git show --pretty=email $commit |\
			scripts/checkpatch.pl $checkpatch_options; then
		rv=1
	fi

	return $rv
}

# turn $1 in to a git commit range
function rangeish()
{
	if [ -z "$1" ]; then
		echo "HEAD^..HEAD"
	elif echo "$1" | grep -q '\.\.'; then
		echo "$1"
	else
		echo "$1..HEAD"
	fi
}

function dim_extract_tags
{
	local branch range file tags

	branch=${1:?$usage}
	range=$(rangeish "${2:-}")
	file=$(mktemp)

	assert_branch $branch
	assert_repo_clean

	cat > $file

	tags=$(message_print_body "$file" | grep -ai '^[^>]*[A-Za-z-]\+: [^ ]')

	rm -f $file

	if [[ -z "$tags" ]]; then
		return 0
	fi

	tags=$(printf -- "# *** extracted tags ***\n%s" "$tags")

	git filter-branch -f --msg-filter "cat ; echo \"$tags\"" $range
}

function dim_extract_queued
{
	dim_extract_tags drm-intel-next-queued "$@"
}

function dim_extract_fixes
{
	dim_extract_tags drm-intel-fixes "$@"
}

function dim_extract_next_fixes
{
	dim_extract_tags drm-intel-next-fixes "$@"
}

dim_alias_cp=checkpatch
function dim_checkpatch
{
	local range profile rv

	range=$(rangeish "${1:-}")
	profile=${2:-}

	for commit in $(git rev-list --reverse $range); do
		if ! checkpatch_commit $commit $profile; then
			rv=1
		fi
	done

	return $rv
}

function _restore_head_on_exit
{
	local original_ref

	original_ref="$(git rev-parse --abbrev-ref HEAD)"

	if [ "$original_ref" == "HEAD" ]; then
		original_ref="$(git rev-parse HEAD)"
	fi

	# we want to expand this now
	# shellcheck disable=SC2064
	trap "git checkout -q $original_ref" EXIT
}

function dim_sparse
{
	local range rv sr prev_sr prev_remapped diff_result remap_log commits

	range=$(rangeish "${1:-}")
	remap_log=$DIM_PREFIX/maintainer-tools/remap-log

	if [ ! -e  $remap_log ]; then
		echo "$remap_log is not compailed, please run make in maintainer-tools dir!"
		exit 1
	fi

	echo "Sparse version: $(sparse --version)"

	_restore_head_on_exit

	# make the initial reference build
	commits=( $(git rev-list --reverse $range) )
	git checkout --detach  ${commits[0]}~ > /dev/null 2>&1
	make -j8 drivers/gpu/drm/ > /dev/null 2>&1

	for commit in "${commits[@]}"; do
		touch --no-create $(git diff --name-only $commit~...$commit)
		prev_sr="$(make C=1 -j$(nproc) drivers/gpu/drm/ 2>&1 1>/dev/null | sort)"

		git checkout --detach $commit >/dev/null 2>&1
		sr="$(make C=1 -j$(nproc) drivers/gpu/drm/ 2>&1 1>/dev/null | sort)"

		prev_remapped="$(echo "$prev_sr" | $remap_log <(git diff HEAD~ | $remap_log))"
		diff_result="$(diff -u <(echo "$prev_remapped") <(echo "$sr") || true)"

		echo "Commit: $(git log -n1 --format='%s' $commit)"
		if [ -n "$diff_result" ]; then
			echo "$diff_result" | grep -E '^[+-]' | grep -E -v '^[+-]{3}'
		else
			echo "Okay!"
		fi
		echo

		if (echo "$diff_result" | grep -q '^+'); then
			rv=1
		fi

		prev_sr="$sr"
	done

	return $rv
}

function dim_checker
{
	rm -f drivers/gpu/drm/i915/*.o drivers/gpu/drm/i915/*.ko
	make C=1 drivers/gpu/drm/i915/i915.ko
}

function prep_pull_mail_greetings
{
	if [ -r $DIM_TEMPLATE_HELLO ]; then
		cat $DIM_TEMPLATE_HELLO
	fi
}

function prep_pull_mail_signature
{
	if [ -r $DIM_TEMPLATE_SIGNATURE ]; then
		cat $DIM_TEMPLATE_SIGNATURE
	fi
}

# print pull mail overview based on tags in $@, if any
# without tags, print a reminder
function prep_pull_mail_overview
{
	local obj

	if [ "$#" = "0" ]; then
		echo "*** PULL REQUEST OVERVIEW HERE ***"
	else
		for tag in "$@"; do
			obj=$(git rev-parse $tag)
			if [[ "$(git cat-file -t $obj)" == "tag" ]] ; then
				echo $tag:
				git cat-file -p $obj | tail -n+6 | sed -n '/^-----BEGIN PGP SIGNATURE-----$/q;p'
			fi
		done
	fi
}

# prepare a pull request mail
# $@: tags, if any, to extract into the pull request overview
function prep_pull_mail
{
	local file
	file=$1
	shift
	prep_pull_mail_greetings > $file
	prep_pull_mail_overview "$@" >> $file
	prep_pull_mail_signature >> $file
}

function dim_create_workdir
{
	local branch branches

	branches=${1:?$usage}

	if [[ "$branches" = "all" ]]; then
		branches=$dim_branches
	fi

	cd $DIM_PREFIX

	for branch in $branches ; do
		if [[ -d $branch ]] ; then
			continue;
		fi

		echo Creating separate workdir for $branch

		if git help worktree &> /dev/null; then
			# native worktree support was added in git 2.5
			cd $DIM_REPO
			$DRY git worktree prune
			$DRY git worktree add $DIM_PREFIX/$branch $branch
			cd $DIM_PREFIX
		else
			$DRY git-new-workdir $DIM_REPO $branch $branch
		fi
	done
}

dim_alias_fw=for-each-workdir
function dim_for_each_workdir
{
	cd $DIM_PREFIX/$DIM_REPO
	"$@"
	for branch in $dim_branches ; do
		if [[ -d $DIM_PREFIX/$branch ]] ; then
			cd $DIM_PREFIX/$branch
			"$@"
		fi
	done
}

function tag_name
{
	local prefix suffix tag
	prefix=$1
	tag="$prefix-$dim_today"
	while git tag -l $tag | grep -q $tag ; do
		tag="$prefix-$dim_today-$((++suffix))"
	done
	echo "$tag"
}

function tag_summary # branch
{
	local branch tag_template
	branch=$1
	tag_template=$DIM_PREFIX/drm-rerere/tag-templates/${branch//\//-}.txt

	if [ -r $tag_template ]; then
		cat $tag_template
	else
		cat <<-EOF
		UAPI Changes:

		Cross-subsystem Changes:

		Core Changes:

		Driver Changes:

		EOF
	fi
}

function tag_branch
{
	local tag branch
	tag=$1
	branch=$2

	tag_summary $branch | $DRY git tag -F- $tag "$branch@{upstream}"
	$DRY git tag -a $DIM_GPG_KEYID -f $tag
}

# $1: commit subject prefix
# $2: file
function dim_update_driver_date
{
	local prefix file driver_date driver_timestamp

	prefix=${1:?$usage}
	file=${2:?$usage}

	driver_date=$(date +%Y%m%d)
	driver_timestamp=$(date +%s)

	$DRY sed -i -e "s/^#define DRIVER_DATE.*\"[0-9]*\"$/#define DRIVER_DATE\t\t\"$driver_date\"/; s/^#define DRIVER_TIMESTAMP.*/#define DRIVER_TIMESTAMP\t$driver_timestamp/" "$file"
	$DRY git add "$file"
	git commit $DRY_RUN -sm "$prefix: Update DRIVER_DATE to $driver_date"
}

function dim_update_next
{
	assert_branch drm-intel-next-queued

	git pull --ff-only

	dim_update_driver_date "drm/i915" "drivers/gpu/drm/i915/i915_drv.h"

	gitk --first-parent drm-intel-next-queued ^$(branch_to_remote drm-next)/drm-next &

	# try to push dinq first in case someone raced
	FORCE=1 dim_push_queued

	dim_update_next_continue
}

function dim_update_next_continue
{
	local remote tag

	assert_branch drm-intel-next-queued

	remote=$(repo_to_remote drm-intel)

	git push $DRY_RUN -f $remote drm-intel-next-queued:drm-intel-next
	tag=$(tag_name "drm-intel-next")

	tag_branch $tag drm-intel-next
	git push $DRY_RUN $remote $tag
}

function dim_tag_branch
{
	local branch upstream remote tag unmerged_tags

	branch=${1:?$usage}
	upstream=$2
	assert_branch $branch
	remote=$(branch_to_remote $branch)

	cd $DIM_PREFIX/$DIM_REPO

	git fetch $remote

	if [ $(git rev-parse $branch) != $(git rev-parse "$branch@{u}") ]; then
		echoerr "ERROR: $branch not up-to-date"
		return 1
	fi

	echo "Tagging current $branch"

	if [[ -n "$upstream" ]]; then
		# If there are unmerged tags, show changes since last
		unmerged_tags=$(git_unmerged_tags "$branch" "$upstream")
		if [[ -n "$unmerged_tags" ]]; then
			upstream="${unmerged_tags%% *}"
		fi

		gitk --first-parent "$branch" "^$upstream" &
	fi

	tag=$(tag_name "$branch")
	tag_branch $tag $branch
	git push $DRY_RUN $remote $tag
}

function dim_tag_next
{
	dim_tag_branch "drm-intel-next"
}

# dim_pull_request branch upstream
function dim_pull_request
{
	local branch upstream remote repo req_file url_list git_url tag

	branch=${1:?$usage}
	upstream=${2:?$usage}
	remote=$(branch_to_remote $branch)
	req_file=$(mktemp)

	if [ "$branch" != "drm-intel-next" ]; then
		assert_branch $branch
	else
		cd $DIM_PREFIX/$DIM_REPO
	fi

	git_fetch_helper ${upstream%%/*}
	echo "Using $upstream as the upstream"

	if [ "$branch" = "drm-intel-next" ]; then
		# drm-intel-next pulls have been tagged using dim update-next
		drm_intel_next_tags=$(git_unmerged_tags "$branch" "$upstream")
		prep_pull_mail $req_file $drm_intel_next_tags
		tag=$(git describe --all --exact "$branch@{upstream}")

		repo="drm-intel"
	else
		tag=$(tag_name "$branch")
		gitk --first-parent "$branch" ^$upstream &
		tag_branch $tag $branch
		$DRY git push $remote $tag
		prep_pull_mail $req_file $tag

		repo=$(branch_to_repo $branch)
	fi

	url_list=${drm_tip_repos[$repo]}
	git_url=$(pick_protocol_url git $url_list)

	git request-pull $upstream $git_url $tag >> $req_file
	$DRY $DIM_MUA -s "[PULL] $branch" \
	     -i $req_file "${dim_pull_request_recipients[@]}"
}

function dim_pull_request_next
{
	upstream=${1:-$(branch_to_remote drm-next)/drm-next}
	dim_pull_request drm-intel-next $upstream
}

function dim_pull_request_fixes
{
	upstream=${1:-origin/master}
	dim_pull_request drm-intel-fixes $upstream
}

function dim_pull_request_next_fixes
{
	upstream=${1:-$(branch_to_remote drm-next)/drm-next}
	dim_pull_request drm-intel-next-fixes $upstream
}

# Note: used by bash completion
function dim_list_upstreams
{
	cd $DIM_PREFIX/$DIM_REPO

	echo origin/master
	echo $(branch_to_remote drm-next)/drm-next
	echo $(branch_to_remote drm-fixes)/drm-fixes
}

# Note: used by bash completion
function dim_list_branches
{
	echo $dim_branches | sed 's/ /\n/g'
}

dim_alias_ub=update-branches
function dim_update_branches
{
	local repo remote intel_remote

	cd $DIM_PREFIX/$DIM_REPO

	fetch_all

	assert_repo_clean

	for branch in $dim_branches ; do
		if ! git_branch_exists $branch ; then
			continue
		fi
		dim_checkout $branch
		repo=$(branch_to_repo $branch)
		remote=$(repo_to_remote $repo)

		if ! $DRY git merge --ff-only $remote/$branch; then
			$DRY git rebase -i
		fi
	done

	cd $DIM_PREFIX/maintainer-tools
	if git_is_current_branch master || git_is_current_branch maintainer-tools; then
		echo "Updating maintainer-tools..."
		git pull --rebase
	fi

	update_rerere_cache
}

function dim_status
{
	local repo remote patches
	local drm_next_upstream drm_fixes_upstream

	cd $DIM_PREFIX/$DIM_REPO

	fetch_all

	for branch in $dim_branches ; do
		repo=$(branch_to_repo $branch)
		remote=$(repo_to_remote $repo)
		drm_next_upstream=$(branch_to_remote drm-fixes)/drm-fixes
		drm_fixes_upstream=$(branch_to_remote drm-next)/drm-next

		patches=$(git log --oneline $remote/$branch ^origin/master \
			^$drm_next_upstream ^$drm_fixes_upstream | wc -l)

		if [[ $patches -ne 0 ]] ; then
			echo $repo/$branch: $patches unmerged patches
		fi
	done
}

function setup_aux_checkout # name url directory
{
	local name url dir remote

	name=$1
	url=$2
	dir=$3

	echo "Setting up $dir ..."

	if [ ! -d $dir ]; then
		if git help worktree &> /dev/null ; then
			cd $DIM_PREFIX/$DIM_REPO
			remote=$(url_to_remote $url)
			if ! git_branch_exists $name ; then
				git_fetch_helper $remote
				git branch --track $name $remote/$name
			fi
			git worktree add $DIM_PREFIX/$dir $name
		else
			git clone --reference=$DIM_PREFIX/$DIM_REPO/.git $url $dir
			cd $dir
			git config remote.origin.url $url
			echo "$(git_dir $DIM_PREFIX/$DIM_REPO)/objects" > $(git_dir)/objects/info/alternates
			git repack -a -d -l
			remote=origin
		fi
	else
		cd $dir
		remote=$(url_to_remote $url)
	fi
	if ! git_branch_exists $name ; then
		git checkout -t $remote/$name
	fi
	cd - > /dev/null
}

function dim_setup
{
	local remote drm_tip_ssh linux_upstream_git

	drm_tip_ssh=ssh://git.freedesktop.org/git/drm-tip
	linux_upstream_git=git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git

	if [[ ! -d "$DIM_PREFIX" ]]; then
		if ask_user "The DIM_PREFIX repository directory '$DIM_PREFIX' doesn't exist. Create?"; then
			mkdir -p "$DIM_PREFIX"
		else
			echoerr "Please set up your DIM_PREFIX repository directory with"
			echoerr "    mkdir -p $DIM_PREFIX"
			echoerr "or update your configuration (see dimrc.sample)."
			exit 1
		fi
	fi

	if [[ ! -d "$DIM_PREFIX/$DIM_REPO" ]]; then
		if ask_user "The DIM_REPO maintainer kernel repository '$DIM_PREFIX/$DIM_REPO' doesn't exist. Clone upstream?"; then
			git clone "$linux_upstream_git" "$DIM_REPO"
		fi
	fi

	if [[ ! -d "$(git_dir $DIM_PREFIX/$DIM_REPO)" ]]; then
		echoerr "No kernel git checkout found in '$DIM_PREFIX/$DIM_REPO'."
		echoerr "Please set up your DIM_REPO maintainer kernel repository at '$DIM_PREFIX/$DIM_REPO' with:"
		echoerr "    cd $DIM_PREFIX"
		echoerr "    git clone $linux_upstream_git $DIM_REPO"
		echoerr "or update your configuration (see dimrc.sample)."
		exit 1
	fi

	if [[ ! -d "$(git_dir $DIM_PREFIX/maintainer-tools)" ]]; then
		echoerr "No maintainer-tools git checkout found in '$DIM_PREFIX/maintainer-tools'."
		echoerr "dim update will not work. Please fix."
	fi

	cd $DIM_PREFIX

	setup_aux_checkout rerere-cache $drm_tip_ssh drm-rerere

	setup_aux_checkout drm-tip $drm_tip_ssh drm-tip

	echo "dim setup successfully completed!"
}

function assert_branch
{
	local branch

	branch=$1

	dim_cd $branch

	if git_is_current_branch $branch ; then
		return 0
	else
		echo "You're on the wrong branch, expected $branch in $PWD"
		return 1
	fi
}

function assert_repo_clean
{
	if [[ -n "$(git status --porcelain --untracked-files=no)" ]]; then
		echo "Repository not clean, aborting."
		exit 1
	fi
}

# Note: used by bash completion
function dim_list_commands
{
	declare -F | grep -o " dim_[a-zA-Z_]*" | sed 's/^ dim_//;s/_/-/g'
}

# Note: used by bash completion
function dim_list_aliases
{
	# use posix mode to omit functions in set output
	( set -o posix; set ) | grep "^dim_alias_[a-zA-Z0-9_]*=" |\
		sed 's/^dim_alias_//;s/=/\t/;s/_/-/g'
}

# Commands that do not require full setup
function list_developer_commands
{
	local -a developer_commands

	developer_commands=(
		# developer commands
		# these should match the developer section in dim.rst
		"checker"
		"checkpatch"
		"cite"
		"fixes"
		"retip"
		"range-diff"
		"sparse"
		"tc"
		# help commands
		"help"
		"usage"
		# include setup
		"setup"
	)

	printf "%s\n" "${developer_commands[@]}"
}

function dim_cat_to_fixup # [branch]
{
	local fixup_file repo branch
	branch=$1

	cd $DIM_PREFIX/drm-tip

	if [ -z "$branch" ]; then
		branch=$(cat .fixup_branch)
	fi

	repo=$(branch_to_repo $branch)
	fixup_file=$(find_fixup_file $repo $branch)

	cat > $fixup_file
	echo "Applied fixup for $branch"
}

function dim_tc
{
	local sha1 tag conf remote_branches

	sha1=${1:?$usage}

	cd $DIM_PREFIX/$DIM_REPO
	tag=$(git tag --contains $sha1 | grep ^v | sort -V | head -n 1)
	if [[ -n "$tag" ]]; then
		echo "$tag"
		return 0
	fi

	# not in a tagged release, show upstream branches
	remote_branches="origin/master"
	for conf in "${drm_tip_config[@]}"; do
		local repo branch override remote

		read -r repo branch override <<< $conf
		remote=$(repo_to_remote $repo)

		remote_branches="$remote_branches $remote/$branch"
	done

	git branch -r --contains $sha1 $remote_branches | sed 's/^ *//' | sort
}

function dim_cite
{
	local sha1

	sha1=${1:?$usage}

	git --git-dir="$DIM_PREFIX/$DIM_REPO/.git" log -1 $sha1 \
	    "--pretty=format:%H (\"%s\")%n" | \
		sed -e 's/\([0-f]\{12\}\)[0-f]*/\1/'
}

function dim_fixes
{
	local sha1 tag

	sha1=${1:?$usage}

	cd $DIM_PREFIX/$DIM_REPO
	echo "Fixes: $(dim_cite $sha1)"

	(
		git show --no-patch $sha1 | \
			sed -e 's/\(Reviewed\|Acked\|Reported\|Signed\)[a-zA-Z-]*-by:/Cc:/' | \
			sed -e 's/^    C[Cc]: */Cc: /' | grep '^Cc: '
		git show $sha1 | scripts/get_maintainer.pl  --email --norolestats --pattern-depth 1 | sed -e "s/^/Cc: /"
	) | awk '!x[$0]++'

	tag=$(git tag --contains $sha1 | grep ^v | sort -V | head -n 1)
	if [[ -n "$tag" ]]; then
		if ! echo "$tag" | grep -q -e "-rc"; then
			echo "Cc: <stable@vger.kernel.org> # ${tag}+"
		fi
	fi
}

function dim_add_missing_cc
{
	local email name matches

	git show | scripts/get_maintainer.pl --email --norolestats --pattern-depth 1 | while read -r cc; do
		email="$(echo "$cc" | sed -e 's/.*<//' -e 's/>.*//')"
		name=''

		if echo "$cc" | grep -q '<'; then
			name="$(echo ${cc/<*/} | sed -e 's/[[:space:]]*\$//')";
		fi

		# Don't add main mailing lists
		if [[ "$email" = "dri-devel@lists.freedesktop.org" || \
		      "$email" = "linux-kernel@vger.kernel.org}" ]]; then
			continue
		fi

		# Variables from the while loop don't propagate,
		# print out a 1 on success
		matches=$(
			git show -s | grep -i "^    Cc:" | sed 's/^ *[Cc][Cc]: *//' | while read -r testcc; do
				testemail="$(echo "$testcc" | sed -e 's/.*<//' -e 's/>.*//')"

				if [ "$testemail" != "$email" ]; then
					if [ -z "$name" ]; then continue; fi

					testname="$(echo ${testcc/<*/} | sed -e 's/[[:space:]]*\$//' -e 's/^[[:space:]]*//')"

					if [ "$testname" != "$name" ]; then continue; fi
				fi

				echo 1
				break
			done
		)

		if [ -z "$matches" ]; then
			$DRY dim_commit_add_tag "Cc: ${cc}"
		fi
	done
}

function dim_help
{
	manpage=$DIM_PREFIX/maintainer-tools/dim.rst
	if [ ! -e "$manpage" ]; then
		manpage=$(dirname $(readlink -f $0))/dim.rst
		if [ ! -e "$manpage" ]; then
			echo "Can't find the man page. See http://cgit.freedesktop.org/drm-tip/tree/dim.rst?h=maintainer-tools"
			exit 1
		fi
	fi

	if hash rst2man 2>/dev/null; then
		renderer="rst2man"
		pager="man -l -"
	else
		renderer="cat"
		pager=${PAGER:-cat}
	fi

	$renderer < $manpage | $pager
}

function dim_usage
{
	echo "usage: $dim [OPTIONS] SUBCOMMAND [ARGUMENTS]"
	echo
	echo "The available subcommands are:"
	if hash column 2>/dev/null; then
		dim_list_commands | column -c 72 | sed 's/^/\t/'
	else
		dim_list_commands | sed 's/^/\t/'
	fi
	echo
	echo "See '$dim help' for more information."
}

#
# Command line options. Global short uppercase variables.
#

DRY_RUN=
INTERACTIVE=
DRY=
FORCE=
HELP=

while getopts hdfis opt; do
	case "$opt" in
		d)
			DRY_RUN=--dry-run
			DRY="echo"
			;;
		f)
			FORCE=1
			;;
		i)
			INTERACTIVE=pause
			;;
		h)
			HELP=1
			;;
		s)
			# FIXME: transitional, do unconditionally at the top
			# when there are no more errors about unbound variables
			set -u
			;;
		*)
			echoerr "See '$dim help' for more information."
			exit
	esac
done
shift $((OPTIND - 1))

# first positional argument is the subcommand
if [ -n "$HELP" ] || [ "$#" = "0" ]; then
	subcommand="usage"
else
	subcommand="$1"
	shift
fi

# generic usage to be used for ${1:?$usage} style argument references
usage="Missing arguments(s) for '$dim $subcommand'. See '$dim help' for usage."

# dim subcommand aliases (with bash 4.3+)
if ! declare -n subcmd=dim_alias_${subcommand//-/_} &> /dev/null || \
		test -z "${subcmd:-}"; then
	subcmd="$subcommand"
fi

# look up the function by the subcommand name
subcmd_func=dim_${subcmd//-/_}
if ! declare -f $subcmd_func >/dev/null; then
	echoerr "'$subcommand' is not a dim command."
	dim_usage
	exit 1
fi

#
# Sanity checks.
#

# Make sure we use 'dim_foo' within dim instead of 'dim foo'.
if [[ -n "${__dim_running:-}" ]]; then
	echoerr "INTERNAL ERROR: do not recurse back to dim"
	exit 1
fi
export __dim_running=1

check_dim_config

# Commands useful for developers don't need a full dim setup
if list_developer_commands | grep -qx $subcmd; then
	if [ -r $DIM_PREFIX/drm-rerere/$dim_integration_config ]; then
		read_integration_config
	fi
else
	for d in $DIM_PREFIX $DIM_PREFIX/$DIM_REPO $DIM_PREFIX/drm-rerere $DIM_PREFIX/drm-tip; do
		if [ ! -d $d ]; then
			echoerr "$d is missing, please check your configuration and/or run dim setup"
			exit 1
		fi
	done

	read_integration_config

	check_for_updates
	check_git_version
fi

# throw away to not confuse list-aliases
unset subcmd

$subcmd_func "$@"