mirror of
https://github.com/denoland/deno.git
synced 2024-11-25 15:29:32 -05:00
56 lines
1.9 KiB
TypeScript
56 lines
1.9 KiB
TypeScript
// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
|
|
import { flatbuffers } from "flatbuffers";
|
|
import * as util from "./util";
|
|
|
|
/* eslint-disable @typescript-eslint/camelcase */
|
|
|
|
// Re-export some types.
|
|
export type Offset = flatbuffers.Offset;
|
|
export class ByteBuffer extends flatbuffers.ByteBuffer {}
|
|
export interface Builder extends flatbuffers.Builder {
|
|
inUse: boolean;
|
|
}
|
|
|
|
const globalBuilder = new flatbuffers.Builder() as Builder;
|
|
globalBuilder.inUse = false;
|
|
|
|
// This is a wrapper around the real Builder .
|
|
// The purpose is to reuse a single ArrayBuffer for every message.
|
|
// We can do this because the "control" messages sent to the privileged
|
|
// side are guaranteed to be used during the call to Deno.core.send().
|
|
export function createBuilder(): Builder {
|
|
// eslint-disable-next-line @typescript-eslint/no-explicit-any
|
|
const gb = globalBuilder as any;
|
|
util.assert(!gb.inUse);
|
|
|
|
let bb = globalBuilder.dataBuffer();
|
|
// Only create a new backing ArrayBuffer if the previous one had grown very
|
|
// large in capacity. This should only happen rarely.
|
|
if (bb.capacity() > 1024) {
|
|
util.log(`realloc flatbuffer ArrayBuffer because it was ${bb.capacity()}`);
|
|
bb = ByteBuffer.allocate(1024);
|
|
}
|
|
gb.bb = bb;
|
|
// Remaining space in the ByteBuffer.
|
|
gb.space = globalBuilder.dataBuffer().capacity();
|
|
// Minimum alignment encountered so far.
|
|
gb.minalign = 1;
|
|
// The vtable for the current table.
|
|
gb.vtable = null;
|
|
// The amount of fields we're actually using.
|
|
gb.vtable_in_use = 0;
|
|
// Whether we are currently serializing a table.
|
|
gb.isNested = false;
|
|
// Starting offset of the current struct/table.
|
|
gb.object_start = 0;
|
|
// List of offsets of all vtables.
|
|
gb.vtables = [];
|
|
// For the current vector being built.
|
|
gb.vector_num_elems = 0;
|
|
// False omits default values from the serialized data
|
|
gb.force_defaults = false;
|
|
|
|
gb.inUse = true;
|
|
|
|
return gb as Builder;
|
|
}
|