Spaces:
Configuration error
Configuration error
; | |
/** | |
* @author jdiaz5513 | |
*/ | |
Object.defineProperty(exports, "__esModule", { value: true }); | |
exports.getStreamFrame = exports.toPackedArrayBuffer = exports.toArrayBuffer = exports.setRoot = exports.readRawPointer = exports.initRoot = exports.getSegment = exports.getRoot = exports.dump = exports.allocateSegment = exports.preallocateSegments = exports.getFramedSegments = exports.initMessage = exports.Message = void 0; | |
const tslib_1 = require("tslib"); | |
const debug_1 = tslib_1.__importDefault(require("debug")); | |
const constants_1 = require("../constants"); | |
const errors_1 = require("../errors"); | |
const util_1 = require("../util"); | |
const arena_1 = require("./arena"); | |
const packing_1 = require("./packing"); | |
const pointers_1 = require("./pointers"); | |
const segment_1 = require("./segment"); | |
const pointer_1 = require("./pointers/pointer"); | |
const struct_1 = require("./pointers/struct"); | |
const trace = debug_1.default("capnp:message"); | |
trace("load"); | |
class Message { | |
/** | |
* A Cap'n Proto message. | |
* | |
* SECURITY WARNING: In nodejs do not pass a Buffer's internal array buffer into this constructor. Pass the buffer | |
* directly and everything will be fine. If not, your message will potentially be initialized with random memory | |
* contents! | |
* | |
* The constructor method creates a new Message, optionally using a provided arena for segment allocation, or a buffer | |
* to read from. | |
* | |
* @constructor {Message} | |
* | |
* @param {AnyArena|ArrayBufferView|ArrayBuffer} [src] The source for the message. | |
* A value of `undefined` will cause the message to initialize with a single segment arena only big enough for the | |
* root pointer; it will expand as you go. This is a reasonable choice for most messages. | |
* | |
* Passing an arena will cause the message to use that arena for its segment allocation. Contents will be accepted | |
* as-is. | |
* | |
* Passing an array buffer view (like `DataView`, `Uint8Array` or `Buffer`) will create a **copy** of the source | |
* buffer; beware of the potential performance cost! | |
* | |
* @param {boolean} [packed] Whether or not the message is packed. If `true` (the default), the message will be | |
* unpacked. | |
* | |
* @param {boolean} [singleSegment] If true, `src` will be treated as a message consisting of a single segment without | |
* a framing header. | |
* | |
*/ | |
constructor(src, packed = true, singleSegment = false) { | |
this._capnp = initMessage(src, packed, singleSegment); | |
if (src && !isAnyArena(src)) | |
preallocateSegments(this); | |
trace("new %s", this); | |
} | |
allocateSegment(byteLength) { | |
return allocateSegment(byteLength, this); | |
} | |
/** | |
* Create a pretty-printed string dump of this message; incredibly useful for debugging. | |
* | |
* WARNING: Do not call this method on large messages! | |
* | |
* @returns {string} A big steaming pile of pretty hex digits. | |
*/ | |
dump() { | |
return dump(this); | |
} | |
/** | |
* Get a struct pointer for the root of this message. This is primarily used when reading a message; it will not | |
* overwrite existing data. | |
* | |
* @template T | |
* @param {StructCtor<T>} RootStruct The struct type to use as the root. | |
* @returns {T} A struct representing the root of the message. | |
*/ | |
getRoot(RootStruct) { | |
return getRoot(RootStruct, this); | |
} | |
/** | |
* Get a segment by its id. | |
* | |
* This will lazily allocate the first segment if it doesn't already exist. | |
* | |
* @param {number} id The segment id. | |
* @returns {Segment} The requested segment. | |
*/ | |
getSegment(id) { | |
return getSegment(id, this); | |
} | |
/** | |
* Initialize a new message using the provided struct type as the root. | |
* | |
* @template T | |
* @param {StructCtor<T>} RootStruct The struct type to use as the root. | |
* @returns {T} An initialized struct pointing to the root of the message. | |
*/ | |
initRoot(RootStruct) { | |
return initRoot(RootStruct, this); | |
} | |
/** | |
* Set the root of the message to a copy of the given pointer. Used internally | |
* to make copies of pointers for default values. | |
* | |
* @param {Pointer} src The source pointer to copy. | |
* @returns {void} | |
*/ | |
setRoot(src) { | |
setRoot(src, this); | |
} | |
/** | |
* Combine the contents of this message's segments into a single array buffer and prepend a stream framing header | |
* containing information about the following segment data. | |
* | |
* @returns {ArrayBuffer} An ArrayBuffer with the contents of this message. | |
*/ | |
toArrayBuffer() { | |
return toArrayBuffer(this); | |
} | |
/** | |
* Like `toArrayBuffer()`, but also applies the packing algorithm to the output. This is typically what you want to | |
* use if you're sending the message over a network link or other slow I/O interface where size matters. | |
* | |
* @returns {ArrayBuffer} A packed message. | |
*/ | |
toPackedArrayBuffer() { | |
return toPackedArrayBuffer(this); | |
} | |
toString() { | |
// eslint-disable-next-line @typescript-eslint/restrict-template-expressions | |
return `Message_arena:${this._capnp.arena}`; | |
} | |
} | |
exports.Message = Message; | |
Message.allocateSegment = allocateSegment; | |
Message.dump = dump; | |
Message.getRoot = getRoot; | |
Message.getSegment = getSegment; | |
Message.initRoot = initRoot; | |
Message.readRawPointer = readRawPointer; | |
Message.toArrayBuffer = toArrayBuffer; | |
Message.toPackedArrayBuffer = toPackedArrayBuffer; | |
function initMessage(src, packed = true, singleSegment = false) { | |
if (src === undefined) { | |
return { | |
arena: new arena_1.SingleSegmentArena(), | |
segments: [], | |
traversalLimit: constants_1.DEFAULT_TRAVERSE_LIMIT, | |
}; | |
} | |
if (isAnyArena(src)) { | |
return { arena: src, segments: [], traversalLimit: constants_1.DEFAULT_TRAVERSE_LIMIT }; | |
} | |
let buf = src; | |
if (isArrayBufferView(buf)) { | |
buf = buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength); | |
} | |
if (packed) | |
buf = packing_1.unpack(buf); | |
if (singleSegment) { | |
return { | |
arena: new arena_1.SingleSegmentArena(buf), | |
segments: [], | |
traversalLimit: constants_1.DEFAULT_TRAVERSE_LIMIT, | |
}; | |
} | |
return { | |
arena: new arena_1.MultiSegmentArena(getFramedSegments(buf)), | |
segments: [], | |
traversalLimit: constants_1.DEFAULT_TRAVERSE_LIMIT, | |
}; | |
} | |
exports.initMessage = initMessage; | |
/** | |
* Given an _unpacked_ message with a segment framing header, this will generate an ArrayBuffer for each segment in | |
* the message. | |
* | |
* This method is not typically called directly, but can be useful in certain cases. | |
* | |
* @static | |
* @param {ArrayBuffer} message An unpacked message with a framing header. | |
* @returns {ArrayBuffer[]} An array of buffers containing the segment data. | |
*/ | |
function getFramedSegments(message) { | |
const dv = new DataView(message); | |
const segmentCount = dv.getUint32(0, true) + 1; | |
const segments = new Array(segmentCount); | |
trace("reading %d framed segments from stream", segmentCount); | |
let byteOffset = 4 + segmentCount * 4; | |
byteOffset += byteOffset % 8; | |
if (byteOffset + segmentCount * 4 > message.byteLength) { | |
throw new Error(errors_1.MSG_INVALID_FRAME_HEADER); | |
} | |
for (let i = 0; i < segmentCount; i++) { | |
const byteLength = dv.getUint32(4 + i * 4, true) * 8; | |
if (byteOffset + byteLength > message.byteLength) { | |
throw new Error(errors_1.MSG_INVALID_FRAME_HEADER); | |
} | |
segments[i] = message.slice(byteOffset, byteOffset + byteLength); | |
byteOffset += byteLength; | |
} | |
return segments; | |
} | |
exports.getFramedSegments = getFramedSegments; | |
/** | |
* This method is called on messages that were constructed with existing data to prepopulate the segments array with | |
* everything we can find in the arena. Each segment will have it's `byteLength` set to the size of its buffer. | |
* | |
* Technically speaking, the message's segments will be "full" after calling this function. Calling this on your own | |
* may void your warranty. | |
* | |
* @param {Message} m The message to allocate. | |
* @returns {void} | |
*/ | |
function preallocateSegments(m) { | |
const numSegments = arena_1.Arena.getNumSegments(m._capnp.arena); | |
if (numSegments < 1) | |
throw new Error(errors_1.MSG_NO_SEGMENTS_IN_ARENA); | |
m._capnp.segments = new Array(numSegments); | |
for (let i = 0; i < numSegments; i++) { | |
// Set up each segment so that they're fully allocated to the extents of the existing buffers. | |
const buffer = arena_1.Arena.getBuffer(i, m._capnp.arena); | |
const segment = new segment_1.Segment(i, m, buffer, buffer.byteLength); | |
m._capnp.segments[i] = segment; | |
} | |
} | |
exports.preallocateSegments = preallocateSegments; | |
function isArrayBufferView(src) { | |
return src.byteOffset !== undefined; | |
} | |
function isAnyArena(o) { | |
return o.kind !== undefined; | |
} | |
function allocateSegment(byteLength, m) { | |
trace("allocating %x bytes for %s", byteLength, m); | |
const res = arena_1.Arena.allocate(byteLength, m._capnp.segments, m._capnp.arena); | |
let s; | |
if (res.id === m._capnp.segments.length) { | |
// Note how we're only allowing new segments in if they're exactly the next one in the array. There is no logical | |
// reason for segments to be created out of order. | |
s = new segment_1.Segment(res.id, m, res.buffer); | |
trace("adding new segment %s", s); | |
m._capnp.segments.push(s); | |
} | |
else if (res.id < 0 || res.id > m._capnp.segments.length) { | |
throw new Error(util_1.format(errors_1.MSG_SEGMENT_OUT_OF_BOUNDS, res.id, m)); | |
} | |
else { | |
s = m._capnp.segments[res.id]; | |
trace("replacing segment %s with buffer (len:%d)", s, res.buffer.byteLength); | |
s.replaceBuffer(res.buffer); | |
} | |
return s; | |
} | |
exports.allocateSegment = allocateSegment; | |
function dump(m) { | |
let r = ""; | |
if (m._capnp.segments.length === 0) { | |
return "================\nNo Segments\n================\n"; | |
} | |
for (let i = 0; i < m._capnp.segments.length; i++) { | |
r += `================\nSegment #${i}\n================\n`; | |
const { buffer, byteLength } = m._capnp.segments[i]; | |
const b = new Uint8Array(buffer, 0, byteLength); | |
r += util_1.dumpBuffer(b); | |
} | |
return r; | |
} | |
exports.dump = dump; | |
function getRoot(RootStruct, m) { | |
const root = new RootStruct(m.getSegment(0), 0); | |
pointer_1.validate(pointers_1.PointerType.STRUCT, root); | |
const ts = pointer_1.getTargetStructSize(root); | |
// Make sure the underlying pointer is actually big enough to hold the data and pointers as specified in the schema. | |
// If not a shallow copy of the struct contents needs to be made before returning. | |
if (ts.dataByteLength < RootStruct._capnp.size.dataByteLength || | |
ts.pointerLength < RootStruct._capnp.size.pointerLength) { | |
trace("need to resize root struct %s", root); | |
struct_1.resize(RootStruct._capnp.size, root); | |
} | |
return root; | |
} | |
exports.getRoot = getRoot; | |
function getSegment(id, m) { | |
const segmentLength = m._capnp.segments.length; | |
if (id === 0 && segmentLength === 0) { | |
// Segment zero is special. If we have no segments in the arena we'll want to allocate a new one and leave room | |
// for the root pointer. | |
const arenaSegments = arena_1.Arena.getNumSegments(m._capnp.arena); | |
if (arenaSegments === 0) { | |
allocateSegment(constants_1.DEFAULT_BUFFER_SIZE, m); | |
} | |
else { | |
// Okay, the arena already has a buffer we can use. This is totally fine. | |
m._capnp.segments[0] = new segment_1.Segment(0, m, arena_1.Arena.getBuffer(0, m._capnp.arena)); | |
} | |
if (!m._capnp.segments[0].hasCapacity(8)) { | |
throw new Error(errors_1.MSG_SEGMENT_TOO_SMALL); | |
} | |
// This will leave room for the root pointer. | |
m._capnp.segments[0].allocate(8); | |
return m._capnp.segments[0]; | |
} | |
if (id < 0 || id >= segmentLength) { | |
throw new Error(util_1.format(errors_1.MSG_SEGMENT_OUT_OF_BOUNDS, id, m)); | |
} | |
return m._capnp.segments[id]; | |
} | |
exports.getSegment = getSegment; | |
function initRoot(RootStruct, m) { | |
const root = new RootStruct(m.getSegment(0), 0); | |
struct_1.initStruct(RootStruct._capnp.size, root); | |
trace("Initialized root pointer %s for %s.", root, m); | |
return root; | |
} | |
exports.initRoot = initRoot; | |
/** | |
* Read a pointer in raw form (a packed message with framing headers). Does not | |
* care or attempt to validate the input beyond parsing the message | |
* segments. | |
* | |
* This is typically used by the compiler to load default values, but can be | |
* useful to work with messages with an unknown schema. | |
* | |
* @param {ArrayBuffer} data The raw data to read. | |
* @returns {Pointer} A root pointer. | |
*/ | |
function readRawPointer(data) { | |
return new pointers_1.Pointer(new Message(data).getSegment(0), 0); | |
} | |
exports.readRawPointer = readRawPointer; | |
function setRoot(src, m) { | |
pointers_1.Pointer.copyFrom(src, new pointers_1.Pointer(m.getSegment(0), 0)); | |
} | |
exports.setRoot = setRoot; | |
function toArrayBuffer(m) { | |
const streamFrame = getStreamFrame(m); | |
// Make sure the first segment is allocated. | |
if (m._capnp.segments.length === 0) | |
getSegment(0, m); | |
const segments = m._capnp.segments; | |
// Add space for the stream framing. | |
const totalLength = streamFrame.byteLength + segments.reduce((l, s) => l + util_1.padToWord(s.byteLength), 0); | |
const out = new Uint8Array(new ArrayBuffer(totalLength)); | |
let o = streamFrame.byteLength; | |
out.set(new Uint8Array(streamFrame)); | |
segments.forEach((s) => { | |
const segmentLength = util_1.padToWord(s.byteLength); | |
out.set(new Uint8Array(s.buffer, 0, segmentLength), o); | |
o += segmentLength; | |
}); | |
return out.buffer; | |
} | |
exports.toArrayBuffer = toArrayBuffer; | |
function toPackedArrayBuffer(m) { | |
const streamFrame = packing_1.pack(getStreamFrame(m)); | |
// Make sure the first segment is allocated. | |
if (m._capnp.segments.length === 0) | |
m.getSegment(0); | |
// NOTE: A copy operation can be avoided here if we capture the intermediate array and use that directly in the copy | |
// loop below, rather than have `pack()` copy it to an ArrayBuffer just to have to copy it again later. If the | |
// intermediate array can be avoided altogether that's even better! | |
const segments = m._capnp.segments.map((s) => packing_1.pack(s.buffer, 0, util_1.padToWord(s.byteLength))); | |
const totalLength = streamFrame.byteLength + segments.reduce((l, s) => l + s.byteLength, 0); | |
const out = new Uint8Array(new ArrayBuffer(totalLength)); | |
let o = streamFrame.byteLength; | |
out.set(new Uint8Array(streamFrame)); | |
segments.forEach((s) => { | |
out.set(new Uint8Array(s), o); | |
o += s.byteLength; | |
}); | |
return out.buffer; | |
} | |
exports.toPackedArrayBuffer = toPackedArrayBuffer; | |
function getStreamFrame(m) { | |
const length = m._capnp.segments.length; | |
if (length === 0) { | |
// Don't bother allocating the first segment, just return a single zero word for the frame header. | |
return new Float64Array(1).buffer; | |
} | |
const frameLength = 4 + length * 4 + (1 - (length % 2)) * 4; | |
const out = new DataView(new ArrayBuffer(frameLength)); | |
trace("Writing message stream frame with segment count: %d.", length); | |
out.setUint32(0, length - 1, true); | |
m._capnp.segments.forEach((s, i) => { | |
trace("Message segment %d word count: %d.", s.id, s.byteLength / 8); | |
out.setUint32(i * 4 + 4, s.byteLength / 8, true); | |
}); | |
return out.buffer; | |
} | |
exports.getStreamFrame = getStreamFrame; | |
//# sourceMappingURL=message.js.map |