From e828bb917383331b66eae3732a82dbecec944add Mon Sep 17 00:00:00 2001
From: Dorian Niemiec <dorian.niemiec@svrjs.org>
Date: Sun, 10 Sep 2023 19:30:29 +0200
Subject: [PATCH] Add warning about worker count limited to one when using Bun
 1.0 and newer with shimmed (not native) clustering module.

---
 config.json |  2 +-
 svr.js      | 48 +++++++++++++++++++++++++++++++++++-------------
 2 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/config.json b/config.json
index f52cc9f..4d3c590 100644
--- a/config.json
+++ b/config.json
@@ -3,7 +3,7 @@
   "port": 80,
   "pubport": 80,
   "page404": "404.html",
-  "timestamp": 1694365365939,
+  "timestamp": 1694366855651,
   "blacklist": [],
   "nonStandardCodes": [],
   "enableCompression": true,
diff --git a/svr.js b/svr.js
index e5979c3..7929ad2 100644
--- a/svr.js
+++ b/svr.js
@@ -151,6 +151,7 @@ if (!singlethreaded) {
     cluster.isMaster = !process.env.NODE_UNIQUE_ID;
     cluster.isPrimary = cluster.isMaster;
     cluster.isWorker = !cluster.isMaster;
+    cluster.__shimmed__ = true;
 
     if (cluster.isWorker) {
       // Shim the cluster.worker object for worker processes
@@ -329,6 +330,7 @@ var SVRJSInitialized = false;
 var exiting = false;
 var reallyExiting = false;
 var crashed = false;
+var threadLimitWarned = false;
 
 function SVRJSFork() {
   // Log
@@ -336,27 +338,47 @@ function SVRJSFork() {
   // Fork new worker
   var newWorker = {};
   try {
-    newWorker = cluster.fork();
+    if (cluster.__shimmed__ && process.isBun && process.versions.bun && process.versions.bun[0] != "0" && !threadLimitWarned) {
+      threadLimitWarned = true;
+      serverconsole.locwarnmessage("SVR.JS limited the number of workers to one, because of startup problems in Bun 1.0 and newer with shimmed (not native) clustering module. Reliability may suffer.");
+    }
+    if (!(cluster.__shimmed__ && process.isBun && process.versions.bun && process.versions.bun[0] != "0" && Object.keys(cluster.workers) > 0)) {
+      newWorker = cluster.fork();
+    } else {
+      if (SVRJSInitialized) serverconsole.locwarnmessage("SVR.JS limited the number of workers to one, because of startup problems in Bun 1.0 and newer with shimmed (not native) clustering module. Reliability may suffer.");
+    }
   } catch (err) {
     if(err.name == "NotImplementedError") {
       // If cluster.fork throws a NotImplementedError, shim cluster module
       cluster.bunShim();
-      newWorker = cluster.fork();
+      if (cluster.__shimmed__ && process.isBun && process.versions.bun && process.versions.bun[0] != "0" && !threadLimitWarned) {
+        threadLimitWarned = true;
+        serverconsole.locwarnmessage("SVR.JS limited the number of workers to one, because of startup problems in Bun 1.0 and newer with shimmed (not native) clustering module. Reliability may suffer.");
+      }
+      if (!(cluster.__shimmed__ && process.isBun && process.versions.bun && process.versions.bun[0] != "0" && Object.keys(cluster.workers) > 0)) {
+        newWorker = cluster.fork();
+      } else {
+        if (SVRJSInitialized) serverconsole.locwarnmessage("SVR.JS limited the number of workers to one, because of startup problems in Bun 1.0 and newer with shimmed (not native) clustering module. Reliability may suffer.");
+      }
     } else {
       throw err;
     }
   }
-  newWorker.on("error", function (err) {
-    if(!reallyExiting) serverconsole.locwarnmessage("There was a problem when handling SVR.JS worker! (from master process side) Reason: " + err.message);
-  });
-  newWorker.on("exit", function () {
-    if (!exiting && Object.keys(cluster.workers).length == 0) {
-      crashed = true;
-      SVRJSFork();
-    }
-  });
-  newWorker.on("message", bruteForceListenerWrapper(newWorker));
-  newWorker.on("message", listenConnListener);
+
+  // Add event listeners
+  if(newWorker.on) {
+    newWorker.on("error", function (err) {
+      if(!reallyExiting) serverconsole.locwarnmessage("There was a problem when handling SVR.JS worker! (from master process side) Reason: " + err.message);
+    });
+    newWorker.on("exit", function () {
+      if (!exiting && Object.keys(cluster.workers).length == 0) {
+        crashed = true;
+        SVRJSFork();
+      }
+    });
+    newWorker.on("message", bruteForceListenerWrapper(newWorker));
+    newWorker.on("message", listenConnListener);
+  }
 }
 
 var http = require("http");