quickjs-async-context.patch

diff --git a/vendor/quickjs/quickjs.c b/vendor/quickjs/quickjs.c
index e32f0f3..15a2721 100644
--- a/vendor/quickjs/quickjs.c
+++ b/vendor/quickjs/quickjs.c
@@ -464,6 +464,8 @@ struct JSContext {
     JSValue array_ctor;
     JSValue regexp_ctor;
     JSValue promise_ctor;
+    /* Embedder async context, captured at reaction registration. */
+    JSValue async_context;
     JSValue native_error_proto[JS_NATIVE_ERROR_COUNT];
     JSValue iterator_ctor;
     JSValue async_iterator_proto;
@@ -875,6 +877,7 @@ typedef struct JSJobEntry {
     struct list_head link;
     JSContext *realm;
     JSJobFunc *job_func;
+    JSValue async_context;
     int argc;
     JSValue argv[0];
 } JSJobEntry;
@@ -1854,6 +1857,7 @@ int JS_EnqueueJob(JSContext *ctx, JSJobFunc *job_func,
         return -1;
     e->realm = JS_DupContext(ctx);
     e->job_func = job_func;
+    e->async_context = JS_DupValue(ctx, ctx->async_context);
     e->argc = argc;
     for(i = 0; i < argc; i++) {
         e->argv[i] = JS_DupValue(ctx, argv[i]);
@@ -1876,7 +1880,7 @@ int JS_ExecutePendingJob(JSRuntime *rt, JSContext **pctx)
 {
     JSContext *ctx;
     JSJobEntry *e;
-    JSValue res;
+    JSValue res, previous_context;
     int i, ret;
 
     if (list_empty(&rt->job_list)) {
@@ -1889,7 +1893,11 @@ int JS_ExecutePendingJob(JSRuntime *rt, JSContext **pctx)
     e = list_entry(rt->job_list.next, JSJobEntry, link);
     list_del(&e->link);
     ctx = e->realm;
+    previous_context = ctx->async_context;
+    ctx->async_context = e->async_context;
     res = e->job_func(ctx, e->argc, (JSValueConst *)e->argv);
+    JS_FreeValue(ctx, ctx->async_context);
+    ctx->async_context = previous_context;
     for(i = 0; i < e->argc; i++)
         JS_FreeValue(ctx, e->argv[i]);
     if (JS_IsException(res))
@@ -1985,6 +1993,7 @@ void JS_FreeRuntime(JSRuntime *rt)
         JSJobEntry *e = list_entry(el, JSJobEntry, link);
         for(i = 0; i < e->argc; i++)
             JS_FreeValueRT(rt, e->argv[i]);
+        JS_FreeValueRT(rt, e->async_context);
         JS_FreeContext(e->realm);
         js_free_rt(rt, e);
     }
@@ -2171,6 +2180,7 @@ JSContext *JS_NewContextRaw(JSRuntime *rt)
     if (!ctx)
         return NULL;
     ctx->header.ref_count = 1;
+    ctx->async_context = JS_UNDEFINED;
     add_gc_object(rt, &ctx->header, JS_GC_OBJ_TYPE_JS_CONTEXT);
 
     ctx->class_proto = js_malloc_rt(rt, sizeof(ctx->class_proto[0]) *
@@ -2313,6 +2323,7 @@ static void JS_MarkContext(JSRuntime *rt, JSContext *ctx,
     JS_MarkValue(rt, ctx->iterator_ctor, mark_func);
     JS_MarkValue(rt, ctx->async_iterator_proto, mark_func);
     JS_MarkValue(rt, ctx->promise_ctor, mark_func);
+    JS_MarkValue(rt, ctx->async_context, mark_func);
     JS_MarkValue(rt, ctx->array_ctor, mark_func);
     JS_MarkValue(rt, ctx->regexp_ctor, mark_func);
     JS_MarkValue(rt, ctx->function_ctor, mark_func);
@@ -2389,6 +2400,7 @@ void JS_FreeContext(JSContext *ctx)
     JS_FreeValue(ctx, ctx->iterator_ctor);
     JS_FreeValue(ctx, ctx->async_iterator_proto);
     JS_FreeValue(ctx, ctx->promise_ctor);
+    JS_FreeValue(ctx, ctx->async_context);
     JS_FreeValue(ctx, ctx->array_ctor);
     JS_FreeValue(ctx, ctx->regexp_ctor);
     JS_FreeValue(ctx, ctx->function_ctor);
@@ -52322,6 +52334,7 @@ typedef struct JSPromiseReactionData {
     struct list_head link; /* not used in promise_reaction_job */
     JSValue resolving_funcs[2];
     JSValue handler;
+    JSValue async_context;
 } JSPromiseReactionData;
 
 JSPromiseStateEnum JS_PromiseState(JSContext *ctx, JSValue promise)
@@ -52349,6 +52362,7 @@ static void promise_reaction_data_free(JSRuntime *rt,
     JS_FreeValueRT(rt, rd->resolving_funcs[0]);
     JS_FreeValueRT(rt, rd->resolving_funcs[1]);
     JS_FreeValueRT(rt, rd->handler);
+    JS_FreeValueRT(rt, rd->async_context);
     js_free_rt(rt, rd);
 }
 
@@ -52356,10 +52370,12 @@ static JSValue promise_reaction_job(JSContext *ctx, int argc,
                                     JSValueConst *argv)
 {
     JSValueConst handler, arg, func;
-    JSValue res, res2;
+    JSValue res, res2, previous_context;
     BOOL is_reject;
 
-    assert(argc == 5);
+    assert(argc == 6);
+    previous_context = ctx->async_context;
+    ctx->async_context = JS_DupValue(ctx, argv[5]);
     handler = argv[2];
     is_reject = JS_ToBool(ctx, argv[3]);
     arg = argv[4];
@@ -52391,6 +52407,8 @@ static JSValue promise_reaction_job(JSContext *ctx, int argc,
     }
     JS_FreeValue(ctx, res);
 
+    JS_FreeValue(ctx, ctx->async_context);
+    ctx->async_context = previous_context;
     return res2;
 }
 
@@ -52408,7 +52426,7 @@ static void fulfill_or_reject_promise(JSContext *ctx, JSValueConst promise,
     JSPromiseData *s = JS_GetOpaque(promise, JS_CLASS_PROMISE);
     struct list_head *el, *el1;
     JSPromiseReactionData *rd;
-    JSValueConst args[5];
+    JSValueConst args[6];
 
     if (!s || s->promise_state != JS_PROMISE_PENDING)
         return; /* should never happen */
@@ -52432,7 +52450,8 @@ static void fulfill_or_reject_promise(JSContext *ctx, JSValueConst promise,
         args[2] = rd->handler;
         args[3] = JS_NewBool(ctx, is_reject);
         args[4] = value;
-        JS_EnqueueJob(ctx, promise_reaction_job, 5, args);
+        args[5] = rd->async_context;
+        JS_EnqueueJob(ctx, promise_reaction_job, 6, args);
         list_del(&rd->link);
         promise_reaction_data_free(ctx->rt, rd);
     }
@@ -52633,6 +52652,7 @@ static void js_promise_mark(JSRuntime *rt, JSValueConst val,
             JS_MarkValue(rt, rd->resolving_funcs[0], mark_func);
             JS_MarkValue(rt, rd->resolving_funcs[1], mark_func);
             JS_MarkValue(rt, rd->handler, mark_func);
+            JS_MarkValue(rt, rd->async_context, mark_func);
         }
     }
     JS_MarkValue(rt, s->promise_result, mark_func);
@@ -53182,6 +53202,7 @@ static __exception int perform_promise_then(JSContext *ctx,
         if (!JS_IsFunction(ctx, handler))
             handler = JS_UNDEFINED;
         rd->handler = JS_DupValue(ctx, handler);
+        rd->async_context = JS_DupValue(ctx, ctx->async_context);
         rd_array[i] = rd;
     }
 
@@ -53189,7 +53210,7 @@ static __exception int perform_promise_then(JSContext *ctx,
         for(i = 0; i < 2; i++)
             list_add_tail(&rd_array[i]->link, &s->promise_reactions[i]);
     } else {
-        JSValueConst args[5];
+        JSValueConst args[6];
         if (s->promise_state == JS_PROMISE_REJECTED && !s->is_handled) {
             JSRuntime *rt = ctx->rt;
             if (rt->host_promise_rejection_tracker) {
@@ -53204,7 +53225,8 @@ static __exception int perform_promise_then(JSContext *ctx,
         args[2] = rd->handler;
         args[3] = JS_NewBool(ctx, i);
         args[4] = s->promise_result;
-        JS_EnqueueJob(ctx, promise_reaction_job, 5, args);
+        args[5] = rd->async_context;
+        JS_EnqueueJob(ctx, promise_reaction_job, 6, args);
         for(i = 0; i < 2; i++)
             promise_reaction_data_free(ctx->rt, rd_array[i]);
     }
@@ -53602,12 +53624,34 @@ static JSClassShortDef const js_async_class_def[] = {
     { JS_ATOM_AsyncGenerator, js_async_generator_finalizer, js_async_generator_mark },  /* JS_CLASS_ASYNC_GENERATOR */
 };
 
+/* Bootstrap consumes and removes these globals before guest evaluation. */
+static JSValue js_get_async_context(JSContext *ctx, JSValueConst this_val,
+                                    int argc, JSValueConst *argv)
+{
+    return JS_DupValue(ctx, ctx->async_context);
+}
+
+static JSValue js_set_async_context(JSContext *ctx, JSValueConst this_val,
+                                    int argc, JSValueConst *argv)
+{
+    JSValue next = JS_DupValue(ctx, argv[0]);
+    JS_FreeValue(ctx, ctx->async_context);
+    ctx->async_context = next;
+    return JS_UNDEFINED;
+}
+
 int JS_AddIntrinsicPromise(JSContext *ctx)
 {
     JSRuntime *rt = ctx->rt;
     JSValue obj1;
     JSCFunctionType ft;
 
+    if (JS_SetPropertyStr(ctx, ctx->global_obj, "__qjsGetAsyncContext",
+          JS_NewCFunction(ctx, js_get_async_context, "getAsyncContext", 0)) < 0 ||
+        JS_SetPropertyStr(ctx, ctx->global_obj, "__qjsSetAsyncContext",
+          JS_NewCFunction(ctx, js_set_async_context, "setAsyncContext", 1)) < 0)
+        return -1;
+
     if (!JS_IsRegisteredClass(rt, JS_CLASS_PROMISE)) {
         if (init_class_range(rt, js_async_class_def, JS_CLASS_PROMISE,
                              countof(js_async_class_def)))