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|
'use strict';
const {
ERR_MULTIPLE_CALLBACK
} = require('internal/errors').codes;
const { Symbol } = primordials;
const kDestroy = Symbol('kDestroy');
const kConstruct = Symbol('kConstruct');
function checkError(err, w, r) {
if (err) {
// Avoid V8 leak, https://github.com/nodejs/node/pull/34103#issuecomment-652002364
err.stack;
if (w && !w.errored) {
w.errored = err;
}
if (r && !r.errored) {
r.errored = err;
}
}
}
// Backwards compat. cb() is undocumented and unused in core but
// unfortunately might be used by modules.
function destroy(err, cb) {
const r = this._readableState;
const w = this._writableState;
// With duplex streams we use the writable side for state.
const s = w || r;
if ((w && w.destroyed) || (r && r.destroyed)) {
if (typeof cb === 'function') {
cb();
}
return this;
}
// We set destroyed to true before firing error callbacks in order
// to make it re-entrance safe in case destroy() is called within callbacks
checkError(err, w, r);
if (w) {
w.destroyed = true;
}
if (r) {
r.destroyed = true;
}
// If still constructing then defer calling _destroy.
if (!s.constructed) {
this.once(kDestroy, function(er) {
_destroy(this, err || er, cb);
});
} else {
_destroy(this, err, cb);
}
return this;
}
function _destroy(self, err, cb) {
let called = false;
const result = self._destroy(err || null, (err) => {
const r = self._readableState;
const w = self._writableState;
called = true;
checkError(err, w, r);
if (w) {
w.closed = true;
}
if (r) {
r.closed = true;
}
if (typeof cb === 'function') {
cb(err);
}
if (err) {
process.nextTick(emitErrorCloseNT, self, err);
} else {
process.nextTick(emitCloseNT, self);
}
});
if (result !== undefined && result !== null) {
try {
const then = result.then;
if (typeof then === 'function') {
then.call(
result,
function() {
if (called)
return;
const r = self._readableState;
const w = self._writableState;
if (w) {
w.closed = true;
}
if (r) {
r.closed = true;
}
if (typeof cb === 'function') {
process.nextTick(cb);
}
process.nextTick(emitCloseNT, self);
},
function(err) {
const r = self._readableState;
const w = self._writableState;
err.stack;
called = true;
if (w && !w.errored) {
w.errored = err;
}
if (r && !r.errored) {
r.errored = err;
}
if (w) {
w.closed = true;
}
if (r) {
r.closed = true;
}
if (typeof cb === 'function') {
process.nextTick(cb, err);
}
process.nextTick(emitErrorCloseNT, self, err);
});
}
} catch (err) {
process.nextTick(emitErrorNT, self, err);
}
}
}
function emitErrorCloseNT(self, err) {
emitErrorNT(self, err);
emitCloseNT(self);
}
function emitCloseNT(self) {
const r = self._readableState;
const w = self._writableState;
if (w) {
w.closeEmitted = true;
}
if (r) {
r.closeEmitted = true;
}
if ((w && w.emitClose) || (r && r.emitClose)) {
self.emit('close');
}
}
function emitErrorNT(self, err) {
const r = self._readableState;
const w = self._writableState;
if ((w && w.errorEmitted) || (r && r.errorEmitted)) {
return;
}
if (w) {
w.errorEmitted = true;
}
if (r) {
r.errorEmitted = true;
}
self.emit('error', err);
}
function undestroy() {
const r = this._readableState;
const w = this._writableState;
if (r) {
r.constructed = true;
r.closed = false;
r.closeEmitted = false;
r.destroyed = false;
r.errored = null;
r.errorEmitted = false;
r.reading = false;
r.ended = false;
r.endEmitted = false;
}
if (w) {
w.constructed = true;
w.destroyed = false;
w.closed = false;
w.closeEmitted = false;
w.errored = null;
w.errorEmitted = false;
w.ended = false;
w.ending = false;
w.finalCalled = false;
w.prefinished = false;
w.finished = false;
}
}
function errorOrDestroy(stream, err, sync) {
// We have tests that rely on errors being emitted
// in the same tick, so changing this is semver major.
// For now when you opt-in to autoDestroy we allow
// the error to be emitted nextTick. In a future
// semver major update we should change the default to this.
const r = stream._readableState;
const w = stream._writableState;
if ((w && w.destroyed) || (r && r.destroyed)) {
return this;
}
if ((r && r.autoDestroy) || (w && w.autoDestroy))
stream.destroy(err);
else if (err) {
// Avoid V8 leak, https://github.com/nodejs/node/pull/34103#issuecomment-652002364
err.stack;
if (w && !w.errored) {
w.errored = err;
}
if (r && !r.errored) {
r.errored = err;
}
if (sync) {
process.nextTick(emitErrorNT, stream, err);
} else {
emitErrorNT(stream, err);
}
}
}
function construct(stream, cb) {
if (typeof stream._construct !== 'function') {
return;
}
const r = stream._readableState;
const w = stream._writableState;
if (r) {
r.constructed = false;
}
if (w) {
w.constructed = false;
}
stream.once(kConstruct, cb);
if (stream.listenerCount(kConstruct) > 1) {
// Duplex
return;
}
process.nextTick(constructNT, stream);
}
function constructNT(stream) {
const r = stream._readableState;
const w = stream._writableState;
// With duplex streams we use the writable side for state.
const s = w || r;
let called = false;
const result = stream._construct((err) => {
if (r) {
r.constructed = true;
}
if (w) {
w.constructed = true;
}
if (called) {
err = new ERR_MULTIPLE_CALLBACK();
} else {
called = true;
}
if (s.destroyed) {
stream.emit(kDestroy, err);
} else if (err) {
errorOrDestroy(stream, err, true);
} else {
process.nextTick(emitConstructNT, stream);
}
});
if (result !== undefined && result !== null) {
try {
const then = result.then;
if (typeof then === 'function') {
then.call(
result,
function() {
// If the callback was invoked, do nothing further.
if (called)
return;
if (r) {
r.constructed = true;
}
if (w) {
w.constructed = true;
}
if (s.destroyed) {
process.nextTick(() => stream.emit(kDestroy));
} else {
process.nextTick(emitConstructNT, stream);
}
},
function(err) {
if (r) {
r.constructed = true;
}
if (w) {
w.constructed = true;
}
called = true;
if (s.destroyed) {
process.nextTick(() => stream.emit(kDestroy, err));
} else {
process.nextTick(errorOrDestroy, stream, err);
}
});
}
} catch (err) {
process.nextTick(emitErrorNT, stream, err);
}
}
}
function emitConstructNT(stream) {
stream.emit(kConstruct);
}
function isRequest(stream) {
return stream && stream.setHeader && typeof stream.abort === 'function';
}
// Normalize destroy for legacy.
function destroyer(stream, err) {
if (isRequest(stream)) return stream.abort();
if (isRequest(stream.req)) return stream.req.abort();
if (typeof stream.destroy === 'function') return stream.destroy(err);
if (typeof stream.close === 'function') return stream.close();
}
module.exports = {
construct,
destroyer,
destroy,
undestroy,
errorOrDestroy
};
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