feat: add Alpine Linux (OpenRC) support

src/systemd.sh

@@ -1,4 +1,16 @@
+# detect init system
+is_systemd=$(type -P systemctl)
+is_openrc=$(type -P rc-service)
+
 install_service() {
+    if [[ $is_systemd ]]; then
+        install_service_systemd $1
+    elif [[ $is_openrc ]]; then
+        install_service_openrc $1
+    fi
+}
+
+install_service_systemd() {
     case $1 in
     $is_core)
         is_doc_site=https://sing-box.sagernet.org/
@@ -56,3 +68,49 @@ WantedBy=multi-user.target"
     systemctl enable $1
     systemctl daemon-reload
 }
+
+install_service_openrc() {
+    case $1 in
+    $is_core)
+        cat >/etc/init.d/$is_core <<EOF
+#!/sbin/openrc-run
+
+name="$is_core_name"
+description="$is_core_name Service"
+command="$is_core_bin"
+command_args="run -c $is_config_json -C $is_conf_dir"
+command_background=true
+pidfile="/run/\${RC_SVCNAME}.pid"
+output_log="/var/log/$is_core/access.log"
+error_log="/var/log/$is_core/error.log"
+
+depend() {
+    need net
+    after firewall
+}
+EOF
+        chmod +x /etc/init.d/$is_core
+        ;;
+    caddy)
+        cat >/etc/init.d/caddy <<EOF
+#!/sbin/openrc-run
+
+name="Caddy"
+description="Caddy web server"
+command="$is_caddy_bin"
+command_args="run --environ --config $is_caddyfile --adapter caddyfile"
+command_background=true
+pidfile="/run/\${RC_SVCNAME}.pid"
+
+depend() {
+    need net
+    after firewall
+}
+EOF
+        chmod +x /etc/init.d/caddy
+        ;;
+    esac
+
+    # enable
+    rc-update add $1 default
+}