process: allow reading umask in workers

Refs: https://github.com/nodejs/node/issues/25448
PR-URL: https://github.com/nodejs/node/pull/25526
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>

1 files changed, 20 insertions, 1 deletions

diff --git a/lib/internal/process/worker_thread_only.js b/lib/internal/process/worker_thread_only.js
index 3fcd052542..b29bc7a390 100644
--- a/lib/internal/process/worker_thread_only.js
+++ b/lib/internal/process/worker_thread_only.js
@@ -15,6 +15,10 @@ const {
   WritableWorkerStdio
 } = require('internal/worker/io');
 
+const {
+  codes: { ERR_WORKER_UNSUPPORTED_OPERATION }
+} = require('internal/errors');
+
 let debuglog;
 function debug(...args) {
   if (!debuglog) {
@@ -118,8 +122,23 @@ function createWorkerFatalExeception(port) {
   };
 }
 
+// The execution of this function itself should not cause any side effects.
+function wrapProcessMethods(binding) {
+  function umask(mask) {
+    // process.umask() is a read-only operation in workers.
+    if (mask !== undefined) {
+      throw new ERR_WORKER_UNSUPPORTED_OPERATION('Setting process.umask()');
+    }
+
+    return binding.umask(mask);
+  }
+
+  return { umask };
+}
+
 module.exports = {
   initializeWorkerStdio,
   createMessageHandler,
-  createWorkerFatalExeception
+  createWorkerFatalExeception,
+  wrapProcessMethods
 };