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#!/bin/sh
#
# An example hook script to blocks unannotated tags from entering.
# Called by git-receive-pack with arguments: refname sha1-old sha1-new
#
# To enable this hook, make this file executable by "chmod +x update".
#
# Config
# ------
# hooks.allowunannotated
#   This boolean sets whether unannotated tags will be allowed into the
#   repository.  By default they won't be.
# hooks.allowdeletetag
#   This boolean sets whether deleting tags will be allowed in the
#   repository.  By default they won't be.
# hooks.allowdeletebranch
#   This boolean sets whether deleting branches will be allowed in the
#   repository.  By default they won't be.
#

# --- Command line
refname="$1"
oldrev="$2"
newrev="$3"

# --- Safety check
if [ -z "$GIT_DIR" ]; then
	echo "Don't run this script from the command line." >&2
	echo " (if you want, you could supply GIT_DIR then run" >&2
	echo "  $0 <ref> <oldrev> <newrev>)" >&2
	exit 1
fi

if [ -z "$refname" -o -z "$oldrev" -o -z "$newrev" ]; then
	echo "Usage: $0 <ref> <oldrev> <newrev>" >&2
	exit 1
fi

# --- Config
allowunannotated=$(git config --bool hooks.allowunannotated)
allowdeletebranch=$(git config --bool hooks.allowdeletebranch)
allowdeletetag=$(git config --bool hooks.allowdeletetag)

# check for no description
projectdesc=$(sed -e '1q' "$GIT_DIR/description")
if [ -z "$projectdesc" -o "$projectdesc" = "Unnamed repository; edit this file to name it for gitweb." ]; then
	echo "*** Project description file hasn't been set" >&2
	exit 1
fi

# --- Check types
# if $newrev is 0000...0000, it's a commit to delete a ref.
if [ "$newrev" = "0000000000000000000000000000000000000000" ]; then
	newrev_type=delete
else
	newrev_type=$(git-cat-file -t $newrev)
fi

case "$refname","$newrev_type" in
	refs/tags/*,commit)
		# un-annotated tag
		short_refname=${refname##refs/tags/}
		if [ "$allowunannotated" != "true" ]; then
			echo "*** The un-annotated tag, $short_refname, is not allowed in this repository" >&2
			echo "*** Use 'git tag [ -a | -s ]' for tags you want to propagate." >&2
			exit 1
		fi
		;;
	refs/tags/*,delete)
		# delete tag
		if [ "$allowdeletetag" != "true" ]; then
			echo "*** Deleting a tag is not allowed in this repository" >&2
			exit 1
		fi
		;;
	refs/tags/*,tag)
		# annotated tag
		;;
	refs/heads/*,commit)
		# branch
		;;
	refs/heads/*,delete)
		# delete branch
		if [ "$allowdeletebranch" != "true" ]; then
			echo "*** Deleting a branch is not allowed in this repository" >&2
			exit 1
		fi
		;;
	refs/remotes/*,commit)
		# tracking branch
		;;
	refs/remotes/*,delete)
		# delete tracking branch
		if [ "$allowdeletebranch" != "true" ]; then
			echo "*** Deleting a tracking branch is not allowed in this repository" >&2
			exit 1
		fi
		;;
	*)
		# Anything else (is there anything else?)
		echo "*** Update hook: unknown type of update to ref $refname of type $newrev_type" >&2
		exit 1
		;;
esac

# --- Finished
exit 0