1 files changed, 77 insertions, 0 deletions
diff --git a/js/dispatch_minimal.ts b/js/dispatch_minimal.ts
new file mode 100644
index 000000000..17d328110
--- /dev/null
+++ b/js/dispatch_minimal.ts
@@ -0,0 +1,77 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+// Do not add flatbuffer dependencies to this module.
+import * as util from "./util";
+import { core } from "./core";
+
+const DISPATCH_MINIMAL_TOKEN = 0xcafe;
+const promiseTableMin = new Map<number, util.Resolvable<number>>();
+let _nextPromiseId = 0;
+
+export function nextPromiseId(): number {
+  return _nextPromiseId++;
+}
+
+export interface RecordMinimal {
+  promiseId: number;
+  opId: number;
+  arg: number;
+  result: number;
+}
+
+/** Determines if a message has the "minimal" serialization format. If false, it
+ * is flatbuffer encoded.
+ */
+export function hasMinimalToken(i32: Int32Array): boolean {
+  return i32[0] == DISPATCH_MINIMAL_TOKEN;
+}
+
+export function recordFromBufMinimal(buf32: Int32Array): null | RecordMinimal {
+  if (hasMinimalToken(buf32)) {
+    return {
+      promiseId: buf32[1],
+      opId: buf32[2],
+      arg: buf32[3],
+      result: buf32[4]
+    };
+  }
+  return null;
+}
+
+const scratch32 = new Int32Array(5);
+const scratchBytes = new Uint8Array(
+  scratch32.buffer,
+  scratch32.byteOffset,
+  scratch32.byteLength
+);
+util.assert(scratchBytes.byteLength === scratch32.length * 4);
+
+export function handleAsyncMsgFromRustMinimal(
+  ui8: Uint8Array,
+  record: RecordMinimal
+): void {
+  // Fast and new
+  util.log("minimal handleAsyncMsgFromRust ", ui8.length);
+  const { promiseId, result } = record;
+  const promise = promiseTableMin.get(promiseId);
+  promiseTableMin.delete(promiseId);
+  promise!.resolve(result);
+}
+
+export function sendAsyncMinimal(
+  opId: number,
+  arg: number,
+  zeroCopy: Uint8Array
+): Promise<number> {
+  const promiseId = nextPromiseId(); // AKA cmdId
+
+  scratch32[0] = DISPATCH_MINIMAL_TOKEN;
+  scratch32[1] = promiseId;
+  scratch32[2] = opId;
+  scratch32[3] = arg;
+
+  const promise = util.createResolvable<number>();
+  promiseTableMin.set(promiseId, promise);
+
+  core.dispatch(scratchBytes, zeroCopy);
+  return promise;
+}