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Diffstat (limited to 'core/shared_queue.js')
| -rw-r--r-- | core/shared_queue.js | 211 |
1 files changed, 0 insertions, 211 deletions
diff --git a/core/shared_queue.js b/core/shared_queue.js deleted file mode 100644 index 1750740d6..000000000 --- a/core/shared_queue.js +++ /dev/null @@ -1,211 +0,0 @@ -// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license. -/* -SharedQueue Binary Layout -+-------------------------------+-------------------------------+ -| NUM_RECORDS (32) | -+---------------------------------------------------------------+ -| NUM_SHIFTED_OFF (32) | -+---------------------------------------------------------------+ -| HEAD (32) | -+---------------------------------------------------------------+ -| OFFSETS (32) | -+---------------------------------------------------------------+ -| RECORD_ENDS (*MAX_RECORDS) ... -+---------------------------------------------------------------+ -| RECORDS (*MAX_RECORDS) ... -+---------------------------------------------------------------+ - */ - -/* eslint-disable @typescript-eslint/no-use-before-define */ - -((window) => { - const GLOBAL_NAMESPACE = "Deno"; - const CORE_NAMESPACE = "core"; - const MAX_RECORDS = 100; - const INDEX_NUM_RECORDS = 0; - const INDEX_NUM_SHIFTED_OFF = 1; - const INDEX_HEAD = 2; - const INDEX_OFFSETS = 3; - const INDEX_RECORDS = INDEX_OFFSETS + 2 * MAX_RECORDS; - const HEAD_INIT = 4 * INDEX_RECORDS; - - // Available on start due to bindings. - const Deno = window[GLOBAL_NAMESPACE]; - const core = Deno[CORE_NAMESPACE]; - // Warning: DO NOT use window.Deno after this point. - // It is possible that the Deno namespace has been deleted. - // Use the above local Deno and core variable instead. - - let sharedBytes; - let shared32; - - let asyncHandlers; - - let initialized = false; - - function maybeInit() { - if (!initialized) { - init(); - initialized = true; - } - } - - function init() { - const shared = Deno.core.shared; - assert(shared.byteLength > 0); - assert(sharedBytes == null); - assert(shared32 == null); - sharedBytes = new Uint8Array(shared); - shared32 = new Int32Array(shared); - asyncHandlers = []; - // Callers should not call Deno.core.recv, use setAsyncHandler. - Deno.core.recv(handleAsyncMsgFromRust); - } - - function ops() { - // op id 0 is a special value to retrieve the map of registered ops. - const opsMapBytes = Deno.core.send(0, new Uint8Array([]), null); - const opsMapJson = String.fromCharCode.apply(null, opsMapBytes); - return JSON.parse(opsMapJson); - } - - function assert(cond) { - if (!cond) { - throw Error("assert"); - } - } - - function reset() { - maybeInit(); - shared32[INDEX_NUM_RECORDS] = 0; - shared32[INDEX_NUM_SHIFTED_OFF] = 0; - shared32[INDEX_HEAD] = HEAD_INIT; - } - - function head() { - maybeInit(); - return shared32[INDEX_HEAD]; - } - - function numRecords() { - return shared32[INDEX_NUM_RECORDS]; - } - - function size() { - return shared32[INDEX_NUM_RECORDS] - shared32[INDEX_NUM_SHIFTED_OFF]; - } - - function setMeta(index, end, opId) { - shared32[INDEX_OFFSETS + 2 * index] = end; - shared32[INDEX_OFFSETS + 2 * index + 1] = opId; - } - - function getMeta(index) { - if (index < numRecords()) { - const buf = shared32[INDEX_OFFSETS + 2 * index]; - const opId = shared32[INDEX_OFFSETS + 2 * index + 1]; - return [opId, buf]; - } else { - return null; - } - } - - function getOffset(index) { - if (index < numRecords()) { - if (index == 0) { - return HEAD_INIT; - } else { - const prevEnd = shared32[INDEX_OFFSETS + 2 * (index - 1)]; - return (prevEnd + 3) & ~3; - } - } else { - return null; - } - } - - function push(opId, buf) { - const off = head(); - const end = off + buf.byteLength; - const alignedEnd = (end + 3) & ~3; - const index = numRecords(); - if (alignedEnd > shared32.byteLength || index >= MAX_RECORDS) { - // console.log("shared_queue.js push fail"); - return false; - } - setMeta(index, end, opId); - assert(alignedEnd % 4 === 0); - assert(end - off == buf.byteLength); - sharedBytes.set(buf, off); - shared32[INDEX_NUM_RECORDS] += 1; - shared32[INDEX_HEAD] = alignedEnd; - return true; - } - - /// Returns null if empty. - function shift() { - const i = shared32[INDEX_NUM_SHIFTED_OFF]; - if (size() == 0) { - assert(i == 0); - return null; - } - - const off = getOffset(i); - const [opId, end] = getMeta(i); - - if (size() > 1) { - shared32[INDEX_NUM_SHIFTED_OFF] += 1; - } else { - reset(); - } - - assert(off != null); - assert(end != null); - const buf = sharedBytes.subarray(off, end); - return [opId, buf]; - } - - function setAsyncHandler(opId, cb) { - maybeInit(); - assert(opId != null); - asyncHandlers[opId] = cb; - } - - function handleAsyncMsgFromRust(opId, buf) { - if (buf) { - // This is the overflow_response case of deno::Isolate::poll(). - asyncHandlers[opId](buf); - } else { - while (true) { - const opIdBuf = shift(); - if (opIdBuf == null) { - break; - } - assert(asyncHandlers[opIdBuf[0]] != null); - asyncHandlers[opIdBuf[0]](opIdBuf[1]); - } - } - } - - function dispatch(opId, control, zeroCopy = null) { - return Deno.core.send(opId, control, zeroCopy); - } - - const denoCore = { - setAsyncHandler, - dispatch, - sharedQueue: { - MAX_RECORDS, - head, - numRecords, - size, - push, - reset, - shift, - }, - ops, - }; - - assert(window[GLOBAL_NAMESPACE] != null); - assert(window[GLOBAL_NAMESPACE][CORE_NAMESPACE] != null); - Object.assign(core, denoCore); -})(this); |