#!/bin/sh

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

# --- Disallow pushing tags

case "$ref" in
    refs/tags/*)
        echo "*** Pushing tags to this repository is not allowed" >&2
        exit 1
        ;;
esac