Add project specific gitconfig and more

This introduces primarily project specific config that includes new
scripts and hook.

Hook checks if commit we push to Gitlab server are correct. There are
multiple checks:
* Check naming convention
* Check base (master vs develop)
* Protect against forgotten develop push when pushing master

In terms of aliases this adds:
git new-mr:
  This opens web browser with new merge request on https://gitlab.nic.cz
  for current branch.
git new-banch:
  This creates new branch interactively and should help users with
  naming convention.

.gitconfig

@@ -0,0 +1,12 @@
+# To use this config run: git config --local include.path ../.gitconfig
+# You also need bash to interpret hooks and scripts
+
+[core]
+	hooksPath = .githooks
+
+[alias]
+	new-mr = "!.gitscripts/new-mr"
+	new-branch = "!.gitscripts/new-branch"
+
+[sendemail]
+	to = [email protected]

.githooks/pre-push

@@ -0,0 +1,76 @@
+#!/bin/bash
+server="gitlab.nic.cz"
+server_old="gitlab.labs.nic.cz"
+
+zero_sha1="0000000000000000000000000000000000000000"
+
+
+is_new_branch() {
+	local remote_sha1="$1"
+	[ "$remote_sha1" = "$zero_sha1" ]
+}
+
+compare_ancestors() {
+	local local_hash="$1"
+	[ "$local_hash" != "$zero_sha1" ] || return 0 # ignore removals
+	git merge-base --is-ancestor \
+		"$(git merge-base "$local_hash" "$2")" \
+		"$(git merge-base "$local_hash" "$3")"
+}
+
+
+remote_name="$1"
+remote_url="$2"
+
+
+if [[ "$remote_url" != *$server* && "$remote_url" != *$server_old* ]]; then
+	# We are interested only in pushes to our server
+	exit 0
+fi
+
+push_master=
+push_develop=
+
+while read -r local_ref local_sha1 remote_ref remote_sha1; do
+	remote_ref="${remote_ref#refs/heads/}"
+	case "$remote_ref" in
+		master)
+			push_master="$local_sha1"
+			;;
+		develop)
+			push_develop="$local_sha1"
+			;;
+		hotfix/*)
+			if compare_ancestors "$local_sha1" master develop; then
+				echo "Reference has invalid ancestor, please base it on top of master: $local_ref" >&2
+				exit 1
+			fi
+			;;
+		feature/*|bugfix/*|refactor/*|hack/*)
+			if compare_ancestors "$local_sha1" develop master; then
+				echo "Reference has invalid ancestor, please base it on top of develop: $local_ref" >&2
+				exit 1
+			fi
+			;;
+		*)
+			# We terminate push only if this tries to create new branch of invalid
+			# name. This allows push to existing branches.
+			if is_new_branch "$remote_sha1"; then
+				echo "Creation of new branch of this name is not allowed: $remote_ref" >&2
+				exit 1
+			fi
+			;;
+	esac
+done
+
+if [ -n "$push_master" ]; then
+	if [ -z "$push_develop" ]; then
+		echo "Develop branch has to be always updated with master branch." >&2
+		echo "Push both at the same time with: git push origin master develop" >&2
+		exit 1
+	fi
+	if ! git merge-base --is-ancestor "$push_master" "$push_develop"; then
+		echo "Tip commit of master is not merged to develop branch." >&2
+		exit 1
+	fi
+fi

.gitscripts/new-branch

@@ -0,0 +1,76 @@
+#!/bin/bash
+
+branch_name="$1"
+branch_base="$2"
+branch_desig="$3"
+
+valid_base() {
+	[[ "$1" == "master" || "$1" == "develop" ]]
+}
+
+valid_desig() {
+	local base="$1"
+	local desig="$2"
+	case "$base" in
+		master)
+			[ "$desig" = "hotfix" ]
+			return
+			;;
+		develop)
+			[[ "$desig" =~ ^(bugfix|feature|refactor|hack)$ ]]
+			return
+			;;
+		*)
+			return 1
+			;;
+	esac
+}
+
+while [ -z "$branch_name" ]; do
+	read -r -p "Branch name: " branch_name
+done
+
+while ! valid_base "$branch_base"; do
+	read -r -p "Branch base ([d]evelop/[m]aster): " branch_base
+	case "$branch_base" in
+		d|dev)
+			branch_base="develop"
+			;;
+		m)
+			branch_base="master"
+			;;
+	esac
+done
+
+while ! valid_desig "$branch_base" "$branch_desig"; do
+	case "$branch_base" in
+		master)
+			branch_desig="hotfix"
+			continue
+			;;
+		develop)
+			read -r -p "Branch designation (bugfix/feature/refactor/hack): " \
+				branch_desig
+			case "$branch_desig" in
+				b|bug)
+					branch_desig="bugfix"
+					;;
+				f)
+					branch_desig="feature"
+					;;
+				r|ref)
+					branch_desig="refactor"
+					;;
+				h)
+					branch_desig="hack"
+					;;
+			esac
+			;;
+	esac
+done
+
+branch="$branch_desig/$branch_name"
+echo "Creating branch: $branch"
+
+git branch "$branch" "$branch_base"
+git switch "$branch"

.gitscripts/new-mr

@@ -0,0 +1,36 @@
+#!/bin/bash
+repo="https://gitlab.nic.cz/turris/turris-os-packages"
+cur_branch="$(git branch --show-current)"
+
+
+open_merge_request() {
+	local target="$1"
+	local url="$repo/-/merge_requests/new?merge_request%5Bsource_branch%5D=$cur_branch&merge_request%5Btarget_branch%5D=$target"
+	if command -v xdg-open >/dev/null; then
+		xdg-open "$url"
+	else
+		echo "Open following URL to create merge request for branch: $cur_branch"
+		echo "$url"
+	fi
+}
+
+
+case "$cur_branch" in
+	master)
+		echo "Master branch is the most stable branch. There is no merge target for it." &2
+		exit 1
+		;;
+	develop)
+		echo "Develop branch is merged only on new Turris OS release." >&2
+		exit 1
+		;;
+	hotfix/*)
+		open_merge_request master
+		;;
+	feature/*|bugfix/*|refacotr/*|hack/*)
+		open_merge_request develop
+		;;
+	*)
+		echo "Merge requests are not supported for this branch." >&2
+		;;
+esac

WORKFLOW.adoc

@@ -273,6 +273,14 @@ Tips for developers and maintainers
 This is collection of various tips and primarily configuration options you can use
 to simplify commands described in this flow.
 
+Use project specific git configuration::
+It is highly advised to use project specific git config. You can apply it by
+running following command:
+[,sh]
+----------------------------------------------------------------------------------
+git config --local include.path ../.gitconfig
+----------------------------------------------------------------------------------
+
 Sign commits and tags with GPG without using `--gpg-sign` and `-s`::
 You can configure global or local git option `commit.gpgSign` and `tag.gpgSign`.
 [,sh]