cg-tag

#!/usr/bin/env bash
#
# Mark certain commit with a tag
# Copyright (c) Petr Baudis, 2005
#
# Creates a tag referencing the given commit (or 'HEAD'). You can then
# use the tag anywhere you specify a commit or tree ID.
#
# cg-tag will try to sign the tag if you give it the -s option.
# You can override the default key choice by passing it the -k argument.
#
# Takes the tag name and optionally the associated ID as arguments.
# When the standard input is not a terminal, it will accept the tag
# description on stdin.
#
# OPTIONS
# -------
# -e:: Run tag description message editor
#	Open editor for the tag description message.
#
# -f:: Overwrite existing tag if exists
#	This will make cg-tag silently overwrite the tag if it already
#	exists.
#
# -m MESSAGE:: Specify tag description message
#	Message associated with the tag, describing it. Multiple -m
#	parameters will cause several description paragraphs to appear.
#
# -M FILE:: Read tag description message from a file
#	Include tag description message from a file (this has the same
#	effect as if you would cat it to stdin).
#
# -k KEYNAME:: Use the given KEYNAME to sign the tag
#	Use the given key to sign the tag, instead of the default one.
#	You can use any key identifier GPG recognizes - the argument
#	is passed verbatim as the '--default-key' argument to GPG.
#
# -s:: Sign the tag by your private key using GPG.
#	Sign the tag by your private key using GPG.
#
# OBJECT_ID::
#	This is most usually the ID of the commit to tag. Tagging
#	other objects than commits is possible, but rather "unusual".

# Testsuite: Marginal (part of t9206-merge-multi-base)

USAGE="cg-tag [-m MESSAGE]... [-e] [-s] [OTHER_OPTIONS] TAG_NAME [OBJECT_ID]"
_git_wc_unneeded=1

. "${COGITO_LIB}"cg-Xlib || exit 1

sign=
keyname=
msgs=()
msgfile=
editor=
force=
while optparse; do
	if optparse -s; then
		sign=1
	elif optparse -k=; then
		keyname="$OPTARG"
	elif optparse -m=; then
		msgs[${#msgs[@]}]="$OPTARG"
	elif optparse -d=; then
		# 20060407 cogito-0.17.1-g382c125
		warn -b "cg-tag -d is obsolete, please use cg-tag -m instead"
		msgs[${#msgs[@]}]="$OPTARG"
	elif optparse -M=; then
		msgfile="$OPTARG"
	elif optparse -e; then
		editor=1
	elif optparse -f; then
		force=1
	else
		optfail
	fi
done

name="${ARGS[0]}"
id="${ARGS[1]}"

[ -n "$name" ] || usage

id="$(cg-object-id -n "$id")" || exit 1
type="$(git-cat-file -t "$id")"
id="${id% *}"

git-check-ref-format "refs/tags/$name" || \
	die "name contains invalid characters"

[ "$force" ] || ! exists_ref "refs/tags/$name" || \
	die "tag already exists ($name)"

[ "$id" ] || id="$(get_ref "$(git-symbolic-ref HEAD)")"


tagdir="$(mktemp -d -t gittag.XXXXXX)"

LOGMSG="$tagdir/log"
LOGMSG2="$tagdir/log2"

written=

for msg in "${msgs[@]}"; do
	[ "$written" ] && echo >>"$LOGMSG"
	echo "$msg" | fmt -s >>"$LOGMSG"
	written=1
done

if [ "$msgfile" ]; then
	[ "$written" ] && echo >>"$LOGMSG"
	cat "$msgfile" >>"$LOGMSG" || exit 1
	written=1
fi

# Always have at least one blank line, to ease the editing for
# the poor people whose text editor has no 'O' command.
[ "$written" ] || { editor_shalluse "$editor" && echo >>"$LOGMSG"; }

editor_comment_start tag
echo "CG: You can edit the following fields to adjust cg-tag's behaviour." >>"$LOGMSG"
echo "CG:" >>"$LOGMSG"
signyn=No; [ "$sign" ] && signyn=Yes
echo "CG: Sign the tag: $signyn" >>"$LOGMSG"
[ -n "$keyname" ] || keyname="(default)"
echo "CG: GPG key name: $keyname" >>"$LOGMSG"
echo "CG:" >>"$LOGMSG"
editor_comment_end tag
editor_msg_end

cp "$LOGMSG" "$LOGMSG2"
if editor_shalluse "$editor"; then
	if [ "$editor" ] && ! editor $commitalways tag t; then
		rm -rf "$tagdir"
		echo "Tag message not modified, tagging aborted" >&2
		exit 1
	fi
	editor_parse_setif signyn "Sign the tag"
	case "$signyn" in
		y|Y|Yes|yes|1|true) sign=1;;
		*) sign=;;
	esac
	editor_parse_setif keyname "GPG key name"
	[ x"$keyname" = x"(default)" ] && keyname=
else
	cat >>"$LOGMSG2"
fi

editor_parse_clean
rm "$LOGMSG2"


cat <<SIGEND >"$tagdir/tag"
object $id
type $type
tag $name
tagger $(git-var GIT_COMMITTER_IDENT)
SIGEND
if [ -s "$LOGMSG" ]; then
	echo >>"$tagdir/tag"
	cat "$LOGMSG" >>"$tagdir/tag"
fi
if [ "$sign" ]; then
	echo >>"$tagdir/tag"
	if ! gpg ${keyname:+--default-key "$keyname"} -bsa "$tagdir/tag"; then
		rm -rf "$tagdir"
		die "error signing the tag"
	fi
	cat "$tagdir/tag.asc" >>"$tagdir/tag"
fi
if ! git-update-ref "refs/tags/$name" "$(git-mktag <"$tagdir/tag")"; then
	rm -rf "$tagdir"
	die "error creating tag"
fi
echo "Tagged $id as $name"

rm -rf "$tagdir"