From daeaa52195e4d578fce6e60a61b044309ab3a871 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Morten=20S=C3=B8rvig?= <morten.sorvig@qt.io>
Date: Fri, 3 Mar 2023 12:50:52 +0100
Subject: [PATCH] Support multiple callbacks.

---
 src/library_async.js | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/library_async.js b/src/library_async.js
index eaa3da9ba..02f435370 100644
--- a/src/library_async.js
+++ b/src/library_async.js
@@ -192,7 +192,7 @@ mergeInto(LibraryManager.library, {
     callStackNameToId: {},
     callStackIdToName: {},
     callStackId: 0,
-    asyncPromiseHandlers: null, // { resolve, reject } pair for when *all* asynchronicity is done
+    asyncPromiseHandlers: [], // { resolve, reject } pairs for when *all* asynchronicity is done
     sleepCallbacks: [], // functions to call every time we sleep
 
     getCallStackId: function(funcName) {
@@ -233,13 +233,12 @@ mergeInto(LibraryManager.library, {
     whenDone: function() {
 #if ASSERTIONS
       assert(Asyncify.currData, 'Tried to wait for an async operation when none is in progress.');
-      assert(!Asyncify.asyncPromiseHandlers, 'Cannot have multiple async operations in flight at once');
 #endif
       return new Promise((resolve, reject) => {
-        Asyncify.asyncPromiseHandlers = {
+        Asyncify.asyncPromiseHandlers.push({
           resolve: resolve,
           reject: reject
-        };
+        });
       });
     },
 
@@ -368,10 +367,11 @@ mergeInto(LibraryManager.library, {
             // that may have called C functions that
             // call `Asyncify.handleSleep()`.
             var asyncPromiseHandlers = Asyncify.asyncPromiseHandlers;
-            if (asyncPromiseHandlers) {
-              Asyncify.asyncPromiseHandlers = null;
-              (isError ? asyncPromiseHandlers.reject : asyncPromiseHandlers.resolve)(asyncWasmReturnValue);
-              handled = true;
+            if (asyncPromiseHandlers.length > 0) {
+                for (handler of asyncPromiseHandlers)
+                    (isError ? handler.reject : handler.resolve)(asyncWasmReturnValue);
+                Asyncify.asyncPromiseHandlers = []
+                handled = true;
             }
           }
           if (isError && !handled) {
-- 
2.37.1 (Apple Git-137.1)