denoland-deno/ext/node/polyfills/_fs/_fs_ftruncate.ts

// 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 { CallbackWithError } from "ext:deno_node/_fs/_fs_common.ts";
import { FsFile } from "ext:deno_fs/30_fs.js";

export function ftruncate(
  fd: number,
  lenOrCallback: number | CallbackWithError,
  maybeCallback?: CallbackWithError,
) {
  const len: number | undefined = typeof lenOrCallback === "number"
    ? lenOrCallback
    : undefined;
  const callback: CallbackWithError = typeof lenOrCallback === "function"
    ? lenOrCallback
    : maybeCallback as CallbackWithError;

  if (!callback) throw new Error("No callback function supplied");

  new FsFile(fd, Symbol.for("Deno.internal.FsFile")).truncate(len).then(
    () => callback(null),
    callback,
  );
}

export function ftruncateSync(fd: number, len?: number) {
  new FsFile(fd, Symbol.for("Deno.internal.FsFile")).truncateSync(len);
}