#!/bin/sh

# Given a git source repo, generate a tarball from the desired branch, modify

# the spec file and upload it to lookaside cache if the tarball unpacks and

# gets patched cleanly.

#

# Usage:

#

#     1. Invoke the script as follows:

#

#           ./sync-upstream.sh upstream-repo

#

#       where upstream-repo is the path to the synced upstream git repo.

#

#    2. Watch the script run.  If it proceeds to building the package, then

#       everything seems good and you just need to test the build after it

#       is complete.  If it exits before the build (you'll know if you read

#       the output of the script) then manual intervention is required to

#       complete the sync.  This will typically happen when a patch fails

#       to apply on the new sources.

#

# Development branch:

#

# * As long as the branch is "master" the repository is treated as

#   development and synchronization updates are fully automatic.

#

# Stable branches:

#

# * Once you branch to a stable Fedora release adjust branch.

#   e.g. release/2.23/master

#

# * Set branch_name to the name of the relase

#   e.g. 2.23

#

# * The sync script will automatically stop before commit, push, build

#   for production branches, so you have to review the results and then

#   do those steps yourself.

#

set -e

# We want to sync from master by default.  Change this if you want to sync from

# another branch.

branch=master

# Avoid slashes in branch name.

branch_name=master

# We can't do anything without an upstream repo

if [ $# -ne 1 ]; then

	echo "Usage: $0 <path-to-upstream-repo>" 1>&2

	exit 1

fi

upstream=$1

srcdir=$(git --git-dir=$upstream/.git describe $branch)

cursrc=$(sed -ne 's/^%define glibcsrcdir  \(.*\)/\1/p' glibc.spec)

# Upstream has not moved forward since the last sync.

# TODO: Some time in the future, we might want to only sync when upstream has

# advanced more than a certain number of commits, say, 42.

if [ "$cursrc" = "$srcdir" ]; then

	echo "+ Already in sync with upstream."

	exit 0

fi

# Generate and gzip the tarball from the desired branch of the repository.

echo "+ Generating tarball."

git --git-dir="$upstream/.git" archive --prefix="$srcdir/" "$branch" \

	> "$srcdir.tar"

gzip -9 "$srcdir.tar"

echo "+ Created $srcdir.tar.gz"

# Our changelog header

cldate=$(date +'%a %b %d %Y')

clname=$(git config --get user.name)

clemail=$(git config --get user.email | sed 's/@/\\@/')

# Getting our version and release number from the spec file.

nv=$(perl -ne 's/^%define glibcversion (.+)/printf("%s-", $1)/e;' \

	  -e 's/^%define glibcrelease ([0-9]+).*/printf("%d\n", $1 + 1)/e;' \

	  glibc.spec)

# Our changelog entry.

changelog="* $cldate $clname <$clemail> - $nv\n- Auto-sync with upstream $branch.\n"

# Change the glibcsrcdir variable, bump up the release number and add an extra

# entry to the changelog.

echo "+ Updating spec file."

perl -pi \

	-e "s/^(%define glibcsrcdir  ).+/\$1$srcdir/;

	    s/^(%define glibcrelease )(\d+)/print(\$1); print(\$2 + 1);'';/e;

	    s/^(%changelog)$/\$1\n$changelog/" \

	glibc.spec

function print_steps {

	echo "+ (a) Updating sources e.g. fedpkg new-sources $srcdir.tar.gz"

	echo "+ (b) Committing changes e.g. git commit -a"

	echo "+ (c) Pushing to fedora e.g. fedpkg push"

	echo "+ (d) Building fedora branch e.g. fedpkg build"

}

function prep_failed {

	# fedpkg prep failed.

	if [ $? -ne 0 ]; then

		echo "+ Source prep failed."

		echo "+ The 'sources' file is unmodified. Manually use $srcdir.tar.gz."

		echo "+ Check the output in $tmpfile and fix things before:"

		print_steps

		false

	fi

}

function build_failed {

	# fedpkg build failed.

	if [ $? -ne 0 ]; then

		echo "+ Building the package failed (or was interrupted)."

		echo "+ Check the koji logs for final status."

		false

	fi

}

echo "+ Testing if fedpkg prep works."

tmpfile=$(mktemp fedpkg-prep.out-XXXX)

trap prep_failed EXIT

fedpkg prep > "$tmpfile" 2>&1

# Remove mess created by fedpkg prep

rm -f "$tmpfile"

rm -rf "$srcdir"

echo "+ Source prep is clean, so we're good to go."

fedpkg new-sources "$srcdir.tar.gz"

if [ $branch == "master" ]; then

	git commit -a -m "Auto-sync with upstream $branch."

	fedpkg push

	trap build_failed EXIT

	fedpkg build

	echo "+ Done!"

else

	echo "+ This is a non-development branch."

	echo "+ Please review the results of the sync."

	echo "+ Once reviewed you need to:"

	print_steps

fi