Add release asset builder

scripts/release-lib.sh

@@ -0,0 +1,46 @@
+#!/bin/sh
+
+# Shared helpers for Narratio's checked-in release scripts. This file is
+# intentionally source-only and has no effect when loaded.
+
+narratio_release_fail() {
+	tool_name=$1
+	shift
+	printf '%s: %s\n' "$tool_name" "$*" >&2
+	exit 1
+}
+
+narratio_release_validate_version() {
+	version=$1
+	case $version in
+		v*.*.*) ;;
+		*) return 1 ;;
+	esac
+	components=${version#v}
+	if [ "$components" = "$version" ]; then
+		return 1
+	fi
+
+	previous_ifs=$IFS
+	IFS=.
+	set -- $components
+	IFS=$previous_ifs
+	if [ "$#" -ne 3 ]; then
+		return 1
+	fi
+	for component in "$@"; do
+		case $component in
+			0 | [1-9]*) ;;
+			*) return 1 ;;
+		esac
+		case $component in
+			*[!0-9]*) return 1 ;;
+		esac
+	done
+}
+
+narratio_release_repo_root() (
+	script_path=$1
+	script_dir=$(CDPATH= cd "$(dirname "$script_path")" && pwd -P) || return 1
+	CDPATH= cd "$script_dir/.." && pwd -P
+)