fix(ext/node): Add fs.readv, fs.readvSync (#23166)

Part of #18218.

Implements `fs.readv` and `fs.readvSync` and enables the corresponding
`node_compat` tests.

ext/node/lib.rs

@@ -371,6 +371,7 @@ deno_core::extension!(deno_node,
     "_fs/_fs_readdir.ts",
     "_fs/_fs_readFile.ts",
     "_fs/_fs_readlink.ts",
+    "_fs/_fs_readv.ts",
     "_fs/_fs_realpath.ts",
     "_fs/_fs_rename.ts",
     "_fs/_fs_rm.ts",

ext/node/polyfills/_fs/_fs_readv.ts

@@ -0,0 +1,130 @@
+// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
+
+// TODO(petamoriken): enable prefer-primordials for node polyfills
+// deno-lint-ignore-file prefer-primordials
+
+import {
+  ERR_INVALID_ARG_TYPE,
+  type ErrnoException,
+} from "ext:deno_node/internal/errors.ts";
+import {
+  getValidatedFd,
+  validateBufferArray,
+} from "ext:deno_node/internal/fs/utils.mjs";
+import { maybeCallback } from "ext:deno_node/_fs/_fs_common.ts";
+import { validateInteger } from "ext:deno_node/internal/validators.mjs";
+import * as io from "ext:deno_io/12_io.js";
+import * as fs from "ext:deno_fs/30_fs.js";
+
+type Callback = (
+  err: ErrnoException | null,
+  bytesRead: number,
+  buffers: readonly ArrayBufferView[],
+) => void;
+
+export function readv(
+  fd: number,
+  buffers: readonly ArrayBufferView[],
+  callback: Callback,
+): void;
+export function readv(
+  fd: number,
+  buffers: readonly ArrayBufferView[],
+  position: number | Callback,
+  callback?: Callback,
+): void {
+  if (typeof fd !== "number") {
+    throw new ERR_INVALID_ARG_TYPE("fd", "number", fd);
+  }
+  fd = getValidatedFd(fd);
+  validateBufferArray(buffers);
+  const cb = maybeCallback(callback || position) as Callback;
+  let pos: number | null = null;
+  if (typeof position === "number") {
+    validateInteger(position, "position", 0);
+    pos = position;
+  }
+
+  if (buffers.length === 0) {
+    process.nextTick(cb, null, 0, buffers);
+    return;
+  }
+
+  const innerReadv = async (
+    fd: number,
+    buffers: readonly ArrayBufferView[],
+    position: number | null,
+  ) => {
+    if (typeof position === "number") {
+      await fs.seek(fd, position, io.SeekMode.Start);
+    }
+
+    let readTotal = 0;
+    let readInBuf = 0;
+    let bufIdx = 0;
+    let buf = buffers[bufIdx];
+    while (bufIdx < buffers.length) {
+      const nread = await io.read(fd, buf);
+      if (nread === null) {
+        break;
+      }
+      readInBuf += nread;
+      if (readInBuf === buf.byteLength) {
+        readTotal += readInBuf;
+        readInBuf = 0;
+        bufIdx += 1;
+        buf = buffers[bufIdx];
+      }
+    }
+    readTotal += readInBuf;
+
+    return readTotal;
+  };
+
+  innerReadv(fd, buffers, pos).then(
+    (numRead) => {
+      cb(null, numRead, buffers);
+    },
+    (err) => cb(err, -1, buffers),
+  );
+}
+
+export function readvSync(
+  fd: number,
+  buffers: readonly ArrayBufferView[],
+  position: number | null = null,
+): number {
+  if (typeof fd !== "number") {
+    throw new ERR_INVALID_ARG_TYPE("fd", "number", fd);
+  }
+  fd = getValidatedFd(fd);
+  validateBufferArray(buffers);
+  if (buffers.length === 0) {
+    return 0;
+  }
+  if (typeof position === "number") {
+    validateInteger(position, "position", 0);
+    fs.seekSync(fd, position, io.SeekMode.Start);
+  }
+
+  let readTotal = 0;
+  let readInBuf = 0;
+  let bufIdx = 0;
+  let buf = buffers[bufIdx];
+  while (bufIdx < buffers.length) {
+    const nread = io.readSync(fd, buf);
+    if (nread === null) {
+      break;
+    }
+    readInBuf += nread;
+    if (readInBuf === buf.byteLength) {
+      readTotal += readInBuf;
+      readInBuf = 0;
+      bufIdx += 1;
+      buf = buffers[bufIdx];
+    }
+  }
+  readTotal += readInBuf;
+
+  return readTotal;
+}

ext/node/polyfills/fs.ts

@@ -110,6 +110,7 @@ import {
 import { write, writeSync } from "ext:deno_node/_fs/_fs_write.mjs";
 // @deno-types="./_fs/_fs_writev.d.ts"
 import { writev, writevSync } from "ext:deno_node/_fs/_fs_writev.mjs";
+import { readv, readvSync } from "ext:deno_node/_fs/_fs_readv.ts";
 import {
   writeFile,
   writeFilePromise,
@@ -250,6 +251,8 @@ export default {
   ReadStream,
   realpath,
   realpathSync,
+  readv,
+  readvSync,
   rename,
   renameSync,
   rmdir,
@@ -353,6 +356,8 @@ export {
   readlinkSync,
   ReadStream,
   readSync,
+  readv,
+  readvSync,
   realpath,
   realpathSync,
   rename,

tests/node_compat/config.jsonc

@@ -334,6 +334,8 @@
       "test-fs-readdir-stack-overflow.js",
       "test-fs-readdir.js",
       "test-fs-readfile-empty.js",
+      "test-fs-readv-sync.js",
+      "test-fs-readv.js",
       "test-fs-realpath-native.js",
       "test-fs-rmdir-recursive-sync-warns-not-found.js",
       "test-fs-rmdir-recursive-sync-warns-on-file.js",

tests/node_compat/test/parallel/test-fs-readv-sync.js

@@ -0,0 +1,100 @@
+// deno-fmt-ignore-file
+// deno-lint-ignore-file
+
+// Copyright Joyent and Node contributors. All rights reserved. MIT license.
+// Taken from Node 18.12.1
+// This file is automatically generated by `tools/node_compat/setup.ts`. Do not modify this file manually.
+
+'use strict';
+
+require('../common');
+const assert = require('assert');
+const fs = require('fs');
+const path = require('path');
+const tmpdir = require('../common/tmpdir');
+
+tmpdir.refresh();
+
+const expected = 'ümlaut. Лорем 運務ホソモ指及 आपको करने विकास 紙読決多密所 أضف';
+
+const exptectedBuff = Buffer.from(expected);
+const expectedLength = exptectedBuff.length;
+
+const filename = path.join(tmpdir.path, 'readv_sync.txt');
+fs.writeFileSync(filename, exptectedBuff);
+
+const allocateEmptyBuffers = (combinedLength) => {
+  const bufferArr = [];
+  // Allocate two buffers, each half the size of exptectedBuff
+  bufferArr[0] = Buffer.alloc(Math.floor(combinedLength / 2));
+  bufferArr[1] = Buffer.alloc(combinedLength - bufferArr[0].length);
+
+  return bufferArr;
+};
+
+// fs.readvSync with array of buffers with all parameters
+{
+  const fd = fs.openSync(filename, 'r');
+
+  const bufferArr = allocateEmptyBuffers(exptectedBuff.length);
+
+  let read = fs.readvSync(fd, [Buffer.from('')], 0);
+  assert.strictEqual(read, 0);
+
+  read = fs.readvSync(fd, bufferArr, 0);
+  assert.strictEqual(read, expectedLength);
+
+  fs.closeSync(fd);
+
+  assert(Buffer.concat(bufferArr).equals(fs.readFileSync(filename)));
+}
+
+// fs.readvSync with array of buffers without position
+{
+  const fd = fs.openSync(filename, 'r');
+
+  const bufferArr = allocateEmptyBuffers(exptectedBuff.length);
+
+  let read = fs.readvSync(fd, [Buffer.from('')]);
+  assert.strictEqual(read, 0);
+
+  read = fs.readvSync(fd, bufferArr);
+  assert.strictEqual(read, expectedLength);
+
+  fs.closeSync(fd);
+
+  assert(Buffer.concat(bufferArr).equals(fs.readFileSync(filename)));
+}
+
+/**
+ * Testing with incorrect arguments
+ */
+const wrongInputs = [false, 'test', {}, [{}], ['sdf'], null, undefined];
+
+{
+  const fd = fs.openSync(filename, 'r');
+
+  wrongInputs.forEach((wrongInput) => {
+    assert.throws(
+      () => fs.readvSync(fd, wrongInput, null), {
+        code: 'ERR_INVALID_ARG_TYPE',
+        name: 'TypeError'
+      }
+    );
+  });
+
+  fs.closeSync(fd);
+}
+
+{
+  // fs.readv with wrong fd argument
+  wrongInputs.forEach((wrongInput) => {
+    assert.throws(
+      () => fs.readvSync(wrongInput),
+      {
+        code: 'ERR_INVALID_ARG_TYPE',
+        name: 'TypeError'
+      }
+    );
+  });
+}

tests/node_compat/test/parallel/test-fs-readv.js

@@ -0,0 +1,102 @@
+// deno-fmt-ignore-file
+// deno-lint-ignore-file
+
+// Copyright Joyent and Node contributors. All rights reserved. MIT license.
+// Taken from Node 18.12.1
+// This file is automatically generated by `tools/node_compat/setup.ts`. Do not modify this file manually.
+
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const path = require('path');
+const fs = require('fs');
+const tmpdir = require('../common/tmpdir');
+
+tmpdir.refresh();
+
+const expected = 'ümlaut. Лорем 運務ホソモ指及 आपको करने विकास 紙読決多密所 أضف';
+
+let cnt = 0;
+const getFileName = () => path.join(tmpdir.path, `readv_${++cnt}.txt`);
+const exptectedBuff = Buffer.from(expected);
+
+const allocateEmptyBuffers = (combinedLength) => {
+  const bufferArr = [];
+  // Allocate two buffers, each half the size of exptectedBuff
+  bufferArr[0] = Buffer.alloc(Math.floor(combinedLength / 2));
+  bufferArr[1] = Buffer.alloc(combinedLength - bufferArr[0].length);
+
+  return bufferArr;
+};
+
+const getCallback = (fd, bufferArr) => {
+  return common.mustSucceed((bytesRead, buffers) => {
+    assert.deepStrictEqual(bufferArr, buffers);
+    const expectedLength = exptectedBuff.length;
+    assert.deepStrictEqual(bytesRead, expectedLength);
+    fs.closeSync(fd);
+
+    assert(Buffer.concat(bufferArr).equals(exptectedBuff));
+  });
+};
+
+// fs.readv with array of buffers with all parameters
+{
+  const filename = getFileName();
+  const fd = fs.openSync(filename, 'w+');
+  fs.writeSync(fd, exptectedBuff);
+
+  const bufferArr = allocateEmptyBuffers(exptectedBuff.length);
+  const callback = getCallback(fd, bufferArr);
+
+  fs.readv(fd, bufferArr, 0, callback);
+}
+
+// fs.readv with array of buffers without position
+{
+  const filename = getFileName();
+  fs.writeFileSync(filename, exptectedBuff);
+  const fd = fs.openSync(filename, 'r');
+
+  const bufferArr = allocateEmptyBuffers(exptectedBuff.length);
+  const callback = getCallback(fd, bufferArr);
+
+  fs.readv(fd, bufferArr, callback);
+}
+
+/**
+ * Testing with incorrect arguments
+ */
+const wrongInputs = [false, 'test', {}, [{}], ['sdf'], null, undefined];
+
+{
+  const filename = getFileName(2);
+  fs.writeFileSync(filename, exptectedBuff);
+  const fd = fs.openSync(filename, 'r');
+
+
+  wrongInputs.forEach((wrongInput) => {
+    assert.throws(
+      () => fs.readv(fd, wrongInput, null, common.mustNotCall()), {
+        code: 'ERR_INVALID_ARG_TYPE',
+        name: 'TypeError'
+      }
+    );
+  });
+
+  fs.closeSync(fd);
+}
+
+{
+  // fs.readv with wrong fd argument
+  wrongInputs.forEach((wrongInput) => {
+    assert.throws(
+      () => fs.readv(wrongInput, common.mustNotCall()),
+      {
+        code: 'ERR_INVALID_ARG_TYPE',
+        name: 'TypeError'
+      }
+    );
+  });
+}

tools/core_import_map.json

@@ -32,6 +32,7 @@
     "ext:deno_node/_fs/_fs_mkdir.ts": "../ext/node/polyfills/_fs/_fs_mkdir.ts",
     "ext:deno_node/_fs/_fs_open.ts": "../ext/node/polyfills/_fs/_fs_open.ts",
     "ext:deno_node/_fs/_fs_read.ts": "../ext/node/polyfills/_fs/_fs_read.ts",
+    "ext:deno_node/_fs/_fs_readv.ts": "../ext/node/polyfills/_fs/_fs_readv.ts",
     "ext:deno_node/_fs/_fs_stat.ts": "../ext/node/polyfills/_fs/_fs_stat.ts",
     "ext:deno_node/_fs/_fs_watch.ts": "../ext/node/polyfills/_fs/_fs_watch.ts",
     "ext:deno_node/_fs/_fs_write.mjs": "../ext/node/polyfills/_fs/_fs_write.mjs",

tools/node_compat/TODO.md

@@ -813,8 +813,6 @@ NOTE: This file should not be manually edited. Please edit `tests/node_compat/co
 - [parallel/test-fs-readlink-type-check.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-readlink-type-check.js)
 - [parallel/test-fs-readv-promises.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-readv-promises.js)
 - [parallel/test-fs-readv-promisify.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-readv-promisify.js)
-- [parallel/test-fs-readv-sync.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-readv-sync.js)
-- [parallel/test-fs-readv.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-readv.js)
 - [parallel/test-fs-ready-event-stream.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-ready-event-stream.js)
 - [parallel/test-fs-realpath-buffer-encoding.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-realpath-buffer-encoding.js)
 - [parallel/test-fs-realpath-on-substed-drive.js](https://github.com/nodejs/node/tree/v18.12.1/test/parallel/test-fs-realpath-on-substed-drive.js)