first commit

app_vue/node_modules/default-gateway/darwin.js

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+"use strict";
+
+const {isIP} = require("net");
+const {release} = require("os");
+const execa = require("execa");
+const dests = new Set(["default", "0.0.0.0", "0.0.0.0/0", "::", "::/0"]);
+
+const args = {
+  v4: ["-rn", "-f", "inet"],
+  v6: ["-rn", "-f", "inet6"],
+};
+
+// The IPv4 gateway is in column 3 in Darwin 19 (macOS 10.15 Catalina) and higher,
+// previously it was in column 5
+const v4IfaceColumn = parseInt(release()) >= 19 ? 3 : 5;
+
+const parse = (stdout, family) => {
+  let result;
+
+  (stdout || "").trim().split("\n").some(line => {
+    const results = line.split(/ +/) || [];
+    const target = results[0];
+    const gateway = results[1];
+    const iface = results[family === "v4" ? v4IfaceColumn : 3];
+    if (dests.has(target) && gateway && isIP(gateway)) {
+      result = {gateway, interface: (iface ? iface : null)};
+      return true;
+    }
+  });
+
+  if (!result) {
+    throw new Error("Unable to determine default gateway");
+  }
+
+  return result;
+};
+
+const promise = async family => {
+  const {stdout} = await execa("netstat", args[family]);
+  return parse(stdout, family);
+};
+
+const sync = family => {
+  const {stdout} = execa.sync("netstat", args[family]);
+  return parse(stdout, family);
+};
+
+module.exports.v4 = () => promise("v4");
+module.exports.v6 = () => promise("v6");
+
+module.exports.v4.sync = () => sync("v4");
+module.exports.v6.sync = () => sync("v6");