zlib: add zstd support

Fixes: #48412
PR-URL: #52100
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>

Author: jkrems

benchmark/zlib/creation.js

@@ -5,7 +5,7 @@ const zlib = require('zlib');
 const bench = common.createBenchmark(main, {
   type: [
     'Deflate', 'DeflateRaw', 'Inflate', 'InflateRaw', 'Gzip', 'Gunzip', 'Unzip',
-    'BrotliCompress', 'BrotliDecompress',
+    'BrotliCompress', 'BrotliDecompress', 'ZstdCompress', 'ZstdDecompress',
   ],
   options: ['true', 'false'],
   n: [5e5],

benchmark/zlib/pipe.js

@@ -7,22 +7,27 @@ const bench = common.createBenchmark(main, {
   inputLen: [1024],
   duration: [5],
   type: ['string', 'buffer'],
-  algorithm: ['gzip', 'brotli'],
+  algorithm: ['gzip', 'brotli', 'zstd'],
 }, {
   test: {
     inputLen: 1024,
     duration: 0.2,
   },
 });
 
+const algorithms = {
+  'gzip': [zlib.createGzip, zlib.createGunzip],
+  'brotli': [zlib.createBrotliCompress, zlib.createBrotliDecompress],
+  'zstd': [zlib.createZstdCompress, zlib.createZstdDecompress],
+};
+
 function main({ inputLen, duration, type, algorithm }) {
   const buffer = Buffer.alloc(inputLen, fs.readFileSync(__filename));
   const chunk = type === 'buffer' ? buffer : buffer.toString('utf8');
 
-  const input = algorithm === 'gzip' ?
-    zlib.createGzip() : zlib.createBrotliCompress();
-  const output = algorithm === 'gzip' ?
-    zlib.createGunzip() : zlib.createBrotliDecompress();
+  const [createCompress, createUncompress] = algorithms[algorithm];
+  const input = createCompress();
+  const output = createUncompress();
 
   let readFromOutput = 0;
   input.pipe(output);

doc/api/errors.md

@@ -3314,6 +3314,12 @@ The requested functionality is not supported in worker threads.
 
 Creation of a [`zlib`][] object failed due to incorrect configuration.
 
+<a id="ERR_ZSTD_INVALID_PARAM"></a>
+
+### `ERR_ZSTD_INVALID_PARAM`
+
+An invalid parameter key was passed during construction of a Zstd stream.
+
 <a id="HPE_CHUNK_EXTENSIONS_OVERFLOW"></a>
 
 ### `HPE_CHUNK_EXTENSIONS_OVERFLOW`

doc/api/zlib.md

@@ -7,7 +7,7 @@
 <!-- source_link=lib/zlib.js -->
 
 The `node:zlib` module provides compression functionality implemented using
-Gzip, Deflate/Inflate, and Brotli.
+Gzip, Deflate/Inflate, Brotli, and Zstd.
 
 To access it:
 
@@ -220,8 +220,8 @@ operations be cached to avoid duplication of effort.
 
 ## Compressing HTTP requests and responses
 
-The `node:zlib` module can be used to implement support for the `gzip`, `deflate`
-and `br` content-encoding mechanisms defined by
+The `node:zlib` module can be used to implement support for the `gzip`, `deflate`,
+`br`, and `zstd` content-encoding mechanisms defined by
 [HTTP](https://tools.ietf.org/html/rfc7230#section-4.2).
 
 The HTTP [`Accept-Encoding`][] header is used within an HTTP request to identify
@@ -284,7 +284,7 @@ const { pipeline } = require('node:stream');
 const request = http.get({ host: 'example.com',
                            path: '/',
                            port: 80,
-                           headers: { 'Accept-Encoding': 'br,gzip,deflate' } });
+                           headers: { 'Accept-Encoding': 'br,gzip,deflate,zstd' } });
 request.on('response', (response) => {
   const output = fs.createWriteStream('example.com_index.html');
 
@@ -306,6 +306,9 @@ request.on('response', (response) => {
     case 'deflate':
       pipeline(response, zlib.createInflate(), output, onError);
       break;
+    case 'zstd':
+      pipeline(response, zlib.createZstdDecompress(), output, onError);
+      break;
     default:
       pipeline(response, output, onError);
       break;
@@ -396,6 +399,9 @@ http.createServer((request, response) => {
   } else if (/\bbr\b/.test(acceptEncoding)) {
     response.writeHead(200, { 'Content-Encoding': 'br' });
     pipeline(raw, zlib.createBrotliCompress(), response, onError);
+  } else if (/\bzstd\b/.test(acceptEncoding)) {
+    response.writeHead(200, { 'Content-Encoding': 'zstd' });
+    pipeline(raw, zlib.createZstdCompress(), response, onError);
   } else {
     response.writeHead(200, {});
     pipeline(raw, response, onError);
@@ -416,6 +422,7 @@ const buffer = Buffer.from('eJzT0yMA', 'base64');
 zlib.unzip(
   buffer,
   // For Brotli, the equivalent is zlib.constants.BROTLI_OPERATION_FLUSH.
+  // For Zstd, the equivalent is zlib.constants.ZSTD_e_flush.
   { finishFlush: zlib.constants.Z_SYNC_FLUSH },
   (err, buffer) => {
     if (err) {
@@ -487,6 +494,16 @@ these options have different ranges than the zlib ones:
 
 See [below][Brotli parameters] for more details on Brotli-specific options.
 
+### For Zstd-based streams
+
+There are equivalents to the zlib options for Zstd-based streams, although
+these options have different ranges than the zlib ones:
+
+* zlib's `level` option matches Zstd's `ZSTD_c_compressionLevel` option.
+* zlib's `windowBits` option matches Zstd's `ZSTD_c_windowLog` option.
+
+See [below][Zstd parameters] for more details on Zstd-specific options.
+
 ## Flushing
 
 Calling [`.flush()`][] on a compression stream will make `zlib` return as much
@@ -701,6 +718,50 @@ These advanced options are available for controlling decompression:
   * Boolean flag enabling “Large Window Brotli” mode (not compatible with the
     Brotli format as standardized in [RFC 7932][]).
 
+### Zstd constants
+
+<!-- YAML
+added: REPLACEME
+-->
+
+There are several options and other constants available for Zstd-based
+streams:
+
+#### Flush operations
+
+The following values are valid flush operations for Zstd-based streams:
+
+* `zlib.constants.ZSTD_e_continue` (default for all operations)
+* `zlib.constants.ZSTD_e_flush` (default when calling `.flush()`)
+* `zlib.constants.ZSTD_e_end` (default for the last chunk)
+
+#### Compressor options
+
+There are several options that can be set on Zstd encoders, affecting
+compression efficiency and speed. Both the keys and the values can be accessed
+as properties of the `zlib.constants` object.
+
+The most important options are:
+
+* `ZSTD_c_compressionLevel`
+  * Set compression parameters according to pre-defined cLevel table. Default
+    level is ZSTD\_CLEVEL\_DEFAULT==3.
+
+#### Pledged Source Size
+
+It's possible to specify the expected total size of the uncompressed input via
+`opts.pledgedSrcSize`. If the size doesn't match at the end of the input,
+compression will fail with the code `ZSTD_error_srcSize_wrong`.
+
+#### Decompressor options
+
+These advanced options are available for controlling decompression:
+
+* `ZSTD_d_windowLogMax`
+  * Select a size limit (in power of 2) beyond which the streaming API will
+    refuse to allocate memory buffer in order to protect the host from
+    unreasonable memory requirements.
+
 ## Class: `Options`
 
 <!-- YAML
@@ -962,6 +1023,51 @@ added: v0.7.0
 Reset the compressor/decompressor to factory defaults. Only applicable to
 the inflate and deflate algorithms.
 
+## Class: `ZstdOptions`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+<!--type=misc-->
+
+Each Zstd-based class takes an `options` object. All options are optional.
+
+* `flush` {integer} **Default:** `zlib.constants.ZSTD_e_continue`
+* `finishFlush` {integer} **Default:** `zlib.constants.ZSTD_e_end`
+* `chunkSize` {integer} **Default:** `16 * 1024`
+* `params` {Object} Key-value object containing indexed [Zstd parameters][].
+* `maxOutputLength` {integer} Limits output size when using
+  [convenience methods][]. **Default:** [`buffer.kMaxLength`][]
+
+For example:
+
+```js
+const stream = zlib.createZstdCompress({
+  chunkSize: 32 * 1024,
+  params: {
+    [zlib.constants.ZSTD_c_compressionLevel]: 10,
+    [zlib.constants.ZSTD_c_checksumFlag]: 1,
+  },
+});
+```
+
+## Class: `zlib.ZstdCompress`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+Compress data using the Zstd algorithm.
+
+## Class: `zlib.ZstdDecompress`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+Decompress data using the Zstd algorithm.
+
 ## `zlib.constants`
 
 <!-- YAML
@@ -1135,6 +1241,26 @@ added: v0.5.8
 
 Creates and returns a new [`Unzip`][] object.
 
+## `zlib.createZstdCompress([options])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `options` {zstd options}
+
+Creates and returns a new [`ZstdCompress`][] object.
+
+## `zlib.createZstdDecompress([options])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `options` {zstd options}
+
+Creates and returns a new [`ZstdDecompress`][] object.
+
 ## Convenience methods
 
 <!--type=misc-->
@@ -1481,11 +1607,54 @@ changes:
 
 Decompress a chunk of data with [`Unzip`][].
 
+### `zlib.zstdCompress(buffer[, options], callback)`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `buffer` {Buffer|TypedArray|DataView|ArrayBuffer|string}
+* `options` {zstd options}
+* `callback` {Function}
+
+### `zlib.zstdCompressSync(buffer[, options])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `buffer` {Buffer|TypedArray|DataView|ArrayBuffer|string}
+* `options` {zstd options}
+
+Compress a chunk of data with [`ZstdCompress`][].
+
+### `zlib.zstdDecompress(buffer[, options], callback)`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `buffer` {Buffer|TypedArray|DataView|ArrayBuffer|string}
+* `options` {zstd options}
+* `callback` {Function}
+
+### `zlib.zstdDecompressSync(buffer[, options])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `buffer` {Buffer|TypedArray|DataView|ArrayBuffer|string}
+* `options` {zstd options}
+
+Decompress a chunk of data with [`ZstdDecompress`][].
+
 [Brotli parameters]: #brotli-constants
 [Cyclic redundancy check]: https://en.wikipedia.org/wiki/Cyclic_redundancy_check
 [Memory usage tuning]: #memory-usage-tuning
 [RFC 7932]: https://www.rfc-editor.org/rfc/rfc7932.txt
 [Streams API]: stream.md
+[Zstd parameters]: #zstd-constants
 [`.flush()`]: #zlibflushkind-callback
 [`Accept-Encoding`]: https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3
 [`BrotliCompress`]: #class-zlibbrotlicompress
@@ -1498,6 +1667,8 @@ Decompress a chunk of data with [`Unzip`][].
 [`InflateRaw`]: #class-zlibinflateraw
 [`Inflate`]: #class-zlibinflate
 [`Unzip`]: #class-zlibunzip
+[`ZstdCompress`]: #class-zlibzstdcompress
+[`ZstdDecompress`]: #class-zlibzstddecompress
 [`buffer.kMaxLength`]: buffer.md#bufferkmaxlength
 [`deflateInit2` and `inflateInit2`]: https://zlib.net/manual.html#Advanced
 [`stream.Transform`]: stream.md#class-streamtransform

lib/internal/errors.js

@@ -1889,3 +1889,4 @@ E('ERR_WORKER_UNSERIALIZABLE_ERROR',
   'Serializing an uncaught exception failed', Error);
 E('ERR_WORKER_UNSUPPORTED_OPERATION',
   '%s is not supported in workers', TypeError);
+E('ERR_ZSTD_INVALID_PARAM', '%s is not a valid zstd parameter', RangeError);

lib/zlib.js

@@ -42,6 +42,7 @@ const {
     ERR_BUFFER_TOO_LARGE,
     ERR_INVALID_ARG_TYPE,
     ERR_OUT_OF_RANGE,
+    ERR_ZSTD_INVALID_PARAM,
   },
   genericNodeError,
 } = require('internal/errors');
@@ -80,9 +81,12 @@ const {
   // Node's compression stream modes (node_zlib_mode)
   DEFLATE, DEFLATERAW, INFLATE, INFLATERAW, GZIP, GUNZIP, UNZIP,
   BROTLI_DECODE, BROTLI_ENCODE,
+  ZSTD_COMPRESS, ZSTD_DECOMPRESS,
   // Brotli operations (~flush levels)
   BROTLI_OPERATION_PROCESS, BROTLI_OPERATION_FLUSH,
   BROTLI_OPERATION_FINISH, BROTLI_OPERATION_EMIT_METADATA,
+  // Zstd end directives (~flush levels)
+  ZSTD_e_continue, ZSTD_e_flush, ZSTD_e_end,
 } = constants;
 
 // Translation table for return codes.
@@ -189,9 +193,11 @@ function zlibOnError(message, errno, code) {
 const FLUSH_BOUND = [
   [ Z_NO_FLUSH, Z_BLOCK ],
   [ BROTLI_OPERATION_PROCESS, BROTLI_OPERATION_EMIT_METADATA ],
+  [ ZSTD_e_continue, ZSTD_e_end ],
 ];
 const FLUSH_BOUND_IDX_NORMAL = 0;
 const FLUSH_BOUND_IDX_BROTLI = 1;
+const FLUSH_BOUND_IDX_ZSTD = 2;
 
 // The base class for all Zlib-style streams.
 function ZlibBase(opts, mode, handle, { flush, finishFlush, fullFlush }) {
@@ -200,13 +206,15 @@ function ZlibBase(opts, mode, handle, { flush, finishFlush, fullFlush }) {
   // The ZlibBase class is not exported to user land, the mode should only be
   // passed in by us.
   assert(typeof mode === 'number');
-  assert(mode >= DEFLATE && mode <= BROTLI_ENCODE);
+  assert(mode >= DEFLATE && mode <= ZSTD_DECOMPRESS);
 
   let flushBoundIdx;
-  if (mode !== BROTLI_ENCODE && mode !== BROTLI_DECODE) {
-    flushBoundIdx = FLUSH_BOUND_IDX_NORMAL;
-  } else {
+  if (mode === BROTLI_ENCODE || mode === BROTLI_DECODE) {
     flushBoundIdx = FLUSH_BOUND_IDX_BROTLI;
+  } else if (mode === ZSTD_COMPRESS || mode === ZSTD_DECOMPRESS) {
+    flushBoundIdx = FLUSH_BOUND_IDX_ZSTD;
+  } else {
+    flushBoundIdx = FLUSH_BOUND_IDX_NORMAL;
   }
 
   if (opts) {
@@ -817,6 +825,89 @@ ObjectSetPrototypeOf(BrotliDecompress.prototype, Brotli.prototype);
 ObjectSetPrototypeOf(BrotliDecompress, Brotli);
 
 
+const zstdDefaultOpts = {
+  flush: ZSTD_e_continue,
+  finishFlush: ZSTD_e_end,
+  fullFlush: ZSTD_e_flush,
+};
+function Zstd(opts, mode, initParamsArray, maxParam) {
+  assert(mode === ZSTD_COMPRESS || mode === ZSTD_DECOMPRESS);
+
+  initParamsArray.fill(-1);
+  if (opts?.params) {
+    ObjectKeys(opts.params).forEach((origKey) => {
+      const key = +origKey;
+      if (NumberIsNaN(key) || key < 0 || key > maxParam ||
+          (initParamsArray[key] | 0) !== -1) {
+        throw new ERR_ZSTD_INVALID_PARAM(origKey);
+      }
+
+      const value = opts.params[origKey];
+      if (typeof value !== 'number' && typeof value !== 'boolean') {
+        throw new ERR_INVALID_ARG_TYPE('options.params[key]',
+                                       'number', opts.params[origKey]);
+      }
+      initParamsArray[key] = value;
+    });
+  }
+
+  const handle = mode === ZSTD_COMPRESS ?
+    new binding.ZstdCompress() : new binding.ZstdDecompress();
+
+  const pledgedSrcSize = opts?.pledgedSrcSize ?? undefined;
+
+  this._writeState = new Uint32Array(2);
+  handle.init(
+    initParamsArray,
+    pledgedSrcSize,
+    this._writeState,
+    processCallback,
+  );
+
+  ReflectApply(ZlibBase, this, [opts, mode, handle, zstdDefaultOpts]);
+}
+ObjectSetPrototypeOf(Zstd.prototype, ZlibBase.prototype);
+ObjectSetPrototypeOf(Zstd, ZlibBase);
+
+
+const kMaxZstdCParam = MathMax(...ObjectKeys(constants).map(
+  (key) => (key.startsWith('ZSTD_c_') ?
+    constants[key] :
+    0),
+));
+
+const zstdInitCParamsArray = new Uint32Array(kMaxZstdCParam + 1);
+
+function ZstdCompress(opts) {
+  if (!(this instanceof ZstdCompress))
+    return new ZstdCompress(opts);
+
+  ReflectApply(Zstd, this,
+               [opts, ZSTD_COMPRESS, zstdInitCParamsArray, kMaxZstdCParam]);
+}
+ObjectSetPrototypeOf(ZstdCompress.prototype, Zstd.prototype);
+ObjectSetPrototypeOf(ZstdCompress, Zstd);
+
+
+const kMaxZstdDParam = MathMax(...ObjectKeys(constants).map(
+  (key) => (key.startsWith('ZSTD_d_') ?
+    constants[key] :
+    0),
+));
+
+const zstdInitDParamsArray = new Uint32Array(kMaxZstdDParam + 1);
+
+function ZstdDecompress(opts) {
+  if (!(this instanceof ZstdDecompress))
+    return new ZstdDecompress(opts);
+
+  ReflectApply(Zstd, this,
+               [opts, ZSTD_DECOMPRESS, zstdInitDParamsArray, kMaxZstdDParam]);
+}
+ObjectSetPrototypeOf(ZstdDecompress.prototype, Zstd.prototype);
+ObjectSetPrototypeOf(ZstdDecompress, Zstd);
+
+
 function createProperty(ctor) {
   return {
     __proto__: null,
@@ -855,6 +946,8 @@ module.exports = {
   Unzip,
   BrotliCompress,
   BrotliDecompress,
+  ZstdCompress,
+  ZstdDecompress,
 
   // Convenience methods.
   // compress/decompress a string or buffer in one step.
@@ -876,6 +969,10 @@ module.exports = {
   brotliCompressSync: createConvenienceMethod(BrotliCompress, true),
   brotliDecompress: createConvenienceMethod(BrotliDecompress, false),
   brotliDecompressSync: createConvenienceMethod(BrotliDecompress, true),
+  zstdCompress: createConvenienceMethod(ZstdCompress, false),
+  zstdCompressSync: createConvenienceMethod(ZstdCompress, true),
+  zstdDecompress: createConvenienceMethod(ZstdDecompress, false),
+  zstdDecompressSync: createConvenienceMethod(ZstdDecompress, true),
 };
 
 ObjectDefineProperties(module.exports, {
@@ -888,6 +985,8 @@ ObjectDefineProperties(module.exports, {
   createUnzip: createProperty(Unzip),
   createBrotliCompress: createProperty(BrotliCompress),
   createBrotliDecompress: createProperty(BrotliDecompress),
+  createZstdCompress: createProperty(ZstdCompress),
+  createZstdDecompress: createProperty(ZstdDecompress),
   constants: {
     __proto__: null,
     configurable: false,

src/node_zlib.cc

@@ -54,6 +54,8 @@ for (const [type, expect] of [
     ['deflateRaw', 'inflateRaw', 'DeflateRaw', 'InflateRaw'],
     ['brotliCompress', 'brotliDecompress',
      'BrotliCompress', 'BrotliDecompress'],
+    ['zstdCompress', 'zstdDecompress',
+     'ZstdCompress', 'ZstdDecompress'],
   ]) {
     zlib[method[0]](expect, opts, common.mustCall((err, result) => {
       zlib[method[1]](result, opts, common.mustCall((err, result) => {

test/fixtures/person.jpg.zst

@@ -11,10 +11,12 @@ const emptyBuffer = Buffer.alloc(0);
     [ zlib.deflateSync, zlib.inflateSync, 'deflate sync' ],
     [ zlib.gzipSync, zlib.gunzipSync, 'gzip sync' ],
     [ zlib.brotliCompressSync, zlib.brotliDecompressSync, 'br sync' ],
+    [ zlib.zstdCompressSync, zlib.zstdDecompressSync, 'zstd sync' ],
     [ promisify(zlib.deflateRaw), promisify(zlib.inflateRaw), 'raw' ],
     [ promisify(zlib.deflate), promisify(zlib.inflate), 'deflate' ],
     [ promisify(zlib.gzip), promisify(zlib.gunzip), 'gzip' ],
     [ promisify(zlib.brotliCompress), promisify(zlib.brotliDecompress), 'br' ],
+    [ promisify(zlib.zstdCompress), promisify(zlib.zstdDecompress), 'zstd' ],
   ]) {
     const compressed = await compress(emptyBuffer);
     const decompressed = await decompress(compressed);

test/parallel/test-zlib-convenience-methods.js

@@ -40,6 +40,7 @@ const unzips = [
   zlib.Inflate(),
   zlib.InflateRaw(),
   zlib.BrotliDecompress(),
+  zlib.ZstdDecompress(),
 ];
 
 nonStringInputs.forEach(common.mustCall((input) => {

test/parallel/test-zlib-empty-buffer.js

@@ -144,6 +144,7 @@ class HashStream extends Stream {
 for (const [ createCompress, createDecompress ] of [
   [ zlib.createGzip, zlib.createGunzip ],
   [ zlib.createBrotliCompress, zlib.createBrotliDecompress ],
+  [ zlib.createZstdCompress, zlib.createZstdDecompress ],
 ]) {
   const inp = new RandomReadStream({ total: 1024, block: 256, jitter: 16 });
   const out = new HashStream();

test/parallel/test-zlib-invalid-input.js

@@ -28,9 +28,10 @@ const zlib = require('node:zlib');
 const { test } = require('node:test');
 
 test('zlib should accept writing after flush', async () => {
-  for (const [createCompress, createDecompress] of [
-    [zlib.createGzip, zlib.createGunzip],
-    [zlib.createBrotliCompress, zlib.createBrotliDecompress],
+  for (const [ createCompress, createDecompress ] of [
+    [ zlib.createGzip, zlib.createGunzip ],
+    [ zlib.createBrotliCompress, zlib.createBrotliDecompress ],
+    [ zlib.createZstdCompress, zlib.createZstdDecompress ],
   ]) {
     const { promise, resolve, reject } = Promise.withResolvers();
     const gzip = createCompress();

test/parallel/test-zlib-random-byte-pipes.js

@@ -28,7 +28,13 @@ const zlib = require('node:zlib');
 const { test } = require('node:test');
 
 test('zlib should properly handle zero byte input', async () => {
-  for (const Compressor of [zlib.Gzip, zlib.BrotliCompress]) {
+  const compressors = [
+    [zlib.Gzip, 20],
+    [zlib.BrotliCompress, 1],
+    [zlib.ZstdCompress, 9],
+  ];
+
+  for (const [Compressor, expected] of compressors) {
     const { promise, resolve, reject } = Promise.withResolvers();
     const gz = Compressor();
     const emptyBuffer = Buffer.alloc(0);
@@ -38,7 +44,6 @@ test('zlib should properly handle zero byte input', async () => {
     });
     gz.on('error', reject);
     gz.on('end', function() {
-      const expected = Compressor === zlib.Gzip ? 20 : 1;
       assert.strictEqual(received, expected,
                          `${received}, ${expected}, ${Compressor.name}`);
       resolve();

test/parallel/test-zlib-write-after-flush.js

@@ -0,0 +1,28 @@
+'use strict';
+require('../common');
+const assert = require('assert');
+const zlib = require('zlib');
+const fixtures = require('../common/fixtures');
+
+const file = fixtures.readSync('person.jpg');
+const chunkSize = 16;
+const compress = new zlib.ZstdCompress();
+
+const chunk = file.slice(0, chunkSize);
+const expectedFull = Buffer.from('KLUv/QBYgAAA/9j/4AAQSkZJRgABAQEASA==', 'base64');
+let actualFull;
+
+compress.write(chunk, function() {
+  compress.flush(function() {
+    const bufs = [];
+    let buf;
+    while ((buf = compress.read()) !== null)
+      bufs.push(buf);
+    actualFull = Buffer.concat(bufs);
+  });
+});
+
+process.once('exit', function() {
+  assert.deepStrictEqual(actualFull.toString('base64'), expectedFull.toString('base64'));
+  assert.deepStrictEqual(actualFull, expectedFull);
+});

test/parallel/test-zlib-zero-byte.js

@@ -0,0 +1,38 @@
+'use strict';
+// Test compressing and uncompressing a string with zstd
+
+const common = require('../common');
+const assert = require('assert');
+const zlib = require('zlib');
+
+const inputString = 'ΩΩLorem ipsum dolor sit amet, consectetur adipiscing eli' +
+                    't. Morbi faucibus, purus at gravida dictum, libero arcu ' +
+                    'convallis lacus, in commodo libero metus eu nisi. Nullam' +
+                    ' commodo, neque nec porta placerat, nisi est fermentum a' +
+                    'ugue, vitae gravida tellus sapien sit amet tellus. Aenea' +
+                    'n non diam orci. Proin quis elit turpis. Suspendisse non' +
+                    ' diam ipsum. Suspendisse nec ullamcorper odio. Vestibulu' +
+                    'm arcu mi, sodales non suscipit id, ultrices ut massa. S' +
+                    'ed ac sem sit amet arcu malesuada fermentum. Nunc sed. ';
+const compressedString = 'KLUv/QRYRQkA9tc9H6AlhTb/z/7/gbTI3kaWLKnbCtkZu/hXm0j' +
+                         'FpNz/VQM2ADMANQBHTuQOpIYzfVv7XGwXrpoIfgXNAB98xW4wV3' +
+                         'vnCF2bjcvWZF2wIZ1vr1mSHHvPHU0TgMGBwUFrF0xqReWcWPO8z' +
+                         'Ny6wMwFUilN+Lg987Zvs2GSRMy6uYvtovK9Uuhgst6l9FQrXLnA' +
+                         '5gpZL7PdI8bO9sDH3tHm73XBzaUK+LjSPNKRmzQ3ZMYEPozdof1' +
+                         '2KcZGfIcLa0PTsdkYqhGcAx/E9mWa8EGEeq0Qou2LTmzgg3YJz/' +
+                         '21OuXSF+TOd662d60Qyb04xC5dOF4b8JFH8mpHAxAAELu3tg1oa' +
+                         'bBEIWaRHdE0l/+0RdEWWIVMAku8TgbiX/4bU+OpLo4UuY1FKDR8' +
+                         'RgBc';
+
+zlib.zstdCompress(inputString, common.mustCall((err, buffer) => {
+  assert(inputString.length > buffer.length);
+
+  zlib.zstdDecompress(buffer, common.mustCall((err, buffer) => {
+    assert.strictEqual(buffer.toString(), inputString);
+  }));
+}));
+
+const buffer = Buffer.from(compressedString, 'base64');
+zlib.zstdDecompress(buffer, common.mustCall((err, buffer) => {
+  assert.strictEqual(buffer.toString(), inputString);
+}));

test/parallel/test-zlib-zstd-flush.js

@@ -0,0 +1,34 @@
+'use strict';
+// Test unzipping a file that was created with a non-node zstd lib,
+// piped in as fast as possible.
+//
+// The compressed fixture was created using the reference CLI:
+// $ zstd -19 test/fixtures/person.jpg -o test/fixtures/person.jpg.zst
+
+const common = require('../common');
+const assert = require('assert');
+const zlib = require('zlib');
+const fixtures = require('../common/fixtures');
+
+const tmpdir = require('../common/tmpdir');
+tmpdir.refresh();
+
+const decompress = new zlib.ZstdDecompress();
+
+const fs = require('fs');
+
+const fixture = fixtures.path('person.jpg.zst');
+const unzippedFixture = fixtures.path('person.jpg');
+const outputFile = tmpdir.resolve('person.jpg');
+const expect = fs.readFileSync(unzippedFixture);
+const inp = fs.createReadStream(fixture);
+const out = fs.createWriteStream(outputFile);
+
+inp.pipe(decompress).pipe(out);
+out.on('close', common.mustCall(() => {
+  const actual = fs.readFileSync(outputFile);
+  assert.strictEqual(actual.length, expect.length);
+  for (let i = 0, l = actual.length; i < l; i++) {
+    assert.strictEqual(actual[i], expect[i], `byte[${i}]`);
+  }
+}));

test/parallel/test-zlib-zstd-from-string.js

@@ -0,0 +1,29 @@
+'use strict';
+require('../common');
+
+// This test ensures that zlib throws a RangeError if the final buffer needs to
+// be larger than kMaxLength and concatenation fails.
+// https://github.com/nodejs/node/pull/1811
+
+const assert = require('assert');
+
+// Change kMaxLength for zlib to trigger the error without having to allocate
+// large Buffers.
+const buffer = require('buffer');
+const oldkMaxLength = buffer.kMaxLength;
+buffer.kMaxLength = 64;
+const zlib = require('zlib');
+buffer.kMaxLength = oldkMaxLength;
+
+// "a".repeat(128), compressed using zstd.
+const encoded = Buffer.from('KLUv/SCARQAAEGFhAQA7BVg=', 'base64');
+
+// Async
+zlib.zstdDecompress(encoded, function(err) {
+  assert.ok(err instanceof RangeError);
+});
+
+// Sync
+assert.throws(function() {
+  zlib.zstdDecompressSync(encoded);
+}, RangeError);

test/parallel/test-zlib-zstd-from-zstd.js

@@ -0,0 +1,37 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const zlib = require('zlib');
+
+function compressWithPledgedSrcSize({ pledgedSrcSize, actualSrcSize }) {
+  return new Promise((resolve, reject) => {
+    const compressor = zlib.createZstdCompress({ pledgedSrcSize });
+    compressor.on('error', (e) => {
+      reject(e);
+    });
+    compressor.on('end', resolve);
+    compressor.write('x'.repeat(actualSrcSize), () => {
+      compressor.end();
+      compressor.resume();
+    });
+  }).then(() => {
+    // Compression should only succeed if sizes match
+    assert.strictEqual(pledgedSrcSize, actualSrcSize);
+  }, (error) => {
+    assert.strictEqual(error.code, 'ZSTD_error_srcSize_wrong');
+    // Size error should only happen when sizes do not match
+    assert.notStrictEqual(pledgedSrcSize, actualSrcSize);
+  }).then(common.mustCall());
+}
+
+compressWithPledgedSrcSize({ pledgedSrcSize: 0, actualSrcSize: 0 });
+
+compressWithPledgedSrcSize({ pledgedSrcSize: 0, actualSrcSize: 42 });
+
+compressWithPledgedSrcSize({ pledgedSrcSize: 13, actualSrcSize: 42 });
+
+compressWithPledgedSrcSize({ pledgedSrcSize: 42, actualSrcSize: 0 });
+
+compressWithPledgedSrcSize({ pledgedSrcSize: 42, actualSrcSize: 13 });
+
+compressWithPledgedSrcSize({ pledgedSrcSize: 42, actualSrcSize: 42 });

test/parallel/test-zlib-zstd-kmaxlength-rangeerror.js

@@ -0,0 +1,134 @@
+'use strict';
+require('../common');
+const fixtures = require('../common/fixtures');
+const assert = require('assert');
+const zlib = require('zlib');
+
+// Test some zstd-specific properties of the zstd streams that can not
+// be easily covered through expanding zlib-only tests.
+
+const sampleBuffer = fixtures.readSync('/pss-vectors.json');
+
+{
+  // Test setting the quality parameter at stream creation:
+  const sizes = [];
+  for (let quality = 1;
+    quality <= 22;
+    quality++) {
+    const encoded = zlib.zstdCompressSync(sampleBuffer, {
+      params: {
+        [zlib.constants.ZSTD_c_compressionLevel]: quality
+      }
+    });
+    sizes.push(encoded.length);
+  }
+
+  // Increasing quality should roughly correspond to decreasing compressed size:
+  for (let i = 0; i < sizes.length - 1; i++) {
+    assert(sizes[i + 1] <= sizes[i] * 1.05, sizes);  // 5 % margin of error.
+  }
+  assert(sizes[0] > sizes[sizes.length - 1], sizes);
+}
+
+{
+  // Test that setting out-of-bounds option values or keys fails.
+  assert.throws(() => {
+    zlib.createZstdCompress({
+      params: {
+        10000: 0
+      }
+    });
+  }, {
+    code: 'ERR_ZSTD_INVALID_PARAM',
+    name: 'RangeError',
+    message: '10000 is not a valid zstd parameter'
+  });
+
+  // Test that accidentally using duplicate keys fails.
+  assert.throws(() => {
+    zlib.createZstdCompress({
+      params: {
+        '0': 0,
+        '00': 0
+      }
+    });
+  }, {
+    code: 'ERR_ZSTD_INVALID_PARAM',
+    name: 'RangeError',
+    message: '00 is not a valid zstd parameter'
+  });
+
+  assert.throws(() => {
+    zlib.createZstdCompress({
+      params: {
+        // This param must be a valid ZSTD_strategy value.
+        [zlib.constants.ZSTD_c_strategy]: 130
+      }
+    });
+  }, {
+    code: 'ERR_ZLIB_INITIALIZATION_FAILED',
+    name: 'Error',
+    message: 'Setting parameter failed'
+  });
+
+  // Test that setting out-of-bounds option values or keys fails.
+  assert.throws(() => {
+    zlib.createZstdDecompress({
+      params: {
+        10000: 0
+      }
+    });
+  }, {
+    code: 'ERR_ZSTD_INVALID_PARAM',
+    name: 'RangeError',
+    message: '10000 is not a valid zstd parameter'
+  });
+
+  // Test that accidentally using duplicate keys fails.
+  assert.throws(() => {
+    zlib.createZstdDecompress({
+      params: {
+        '0': 0,
+        '00': 0
+      }
+    });
+  }, {
+    code: 'ERR_ZSTD_INVALID_PARAM',
+    name: 'RangeError',
+    message: '00 is not a valid zstd parameter'
+  });
+
+  assert.throws(() => {
+    zlib.createZstdDecompress({
+      params: {
+        // This param must be >= 10 (ZSTD_WINDOWLOG_ABSOLUTEMIN).
+        [zlib.constants.ZSTD_d_windowLogMax]: 1
+      }
+    });
+  }, {
+    code: 'ERR_ZLIB_INITIALIZATION_FAILED',
+    name: 'Error',
+    message: 'Setting parameter failed'
+  });
+}
+
+{
+  // Test options.flush range
+  assert.throws(() => {
+    zlib.zstdCompressSync('', { flush: zlib.constants.Z_FINISH });
+  }, {
+    code: 'ERR_OUT_OF_RANGE',
+    name: 'RangeError',
+    message: 'The value of "options.flush" is out of range. It must be >= 0 ' +
+      'and <= 2. Received 4',
+  });
+
+  assert.throws(() => {
+    zlib.zstdCompressSync('', { finishFlush: zlib.constants.Z_FINISH });
+  }, {
+    code: 'ERR_OUT_OF_RANGE',
+    name: 'RangeError',
+    message: 'The value of "options.finishFlush" is out of range. It must be ' +
+      '>= 0 and <= 2. Received 4',
+  });
+}

test/parallel/test-zlib-zstd-pledged-src-size.js

@@ -42,6 +42,7 @@ let zlibPairs = [
   [zlib.Gzip, zlib.Unzip],
   [zlib.DeflateRaw, zlib.InflateRaw],
   [zlib.BrotliCompress, zlib.BrotliDecompress],
+  [zlib.ZstdCompress, zlib.ZstdDecompress],
 ];
 
 // How fast to trickle through the slowstream

test/parallel/test-zlib-zstd.js

@@ -252,6 +252,7 @@ const customTypesMap = {
   'X509Certificate': 'crypto.html#class-x509certificate',
 
   'zlib options': 'zlib.html#class-options',
+  'zstd options': 'zlib.html#class-zstdoptions',
 
   'ReadableStream':
     'webstreams.html#class-readablestream',