From a4d6f78619ca63b512c1bfe134b90d3ff4696584 Mon Sep 17 00:00:00 2001
From: Darshan Sen <raisinten@gmail.com>
Date: Sat, 3 Apr 2021 21:14:32 +0530
Subject: [PATCH] fs: move constants to internal/fs/utils.js

Refs: https://github.com/nodejs/node/pull/38004#discussion_r604951958

PR-URL: https://github.com/nodejs/node/pull/38061
Backport-PR-URL: https://github.com/nodejs/node/pull/39838
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Nitzan Uziely <linkgoron@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
 lib/fs.js                            | 10 ++++------
 lib/internal/fs/promises.js          | 16 ++++++----------
 lib/internal/fs/read_file_context.js | 16 +++++++---------
 lib/internal/fs/utils.js             | 21 +++++++++++++++++++++
 4 files changed, 38 insertions(+), 25 deletions(-)

diff --git a/lib/fs.js b/lib/fs.js
index 6c402d1e6b7335..836550e7c283cb 100644
--- a/lib/fs.js
+++ b/lib/fs.js
@@ -24,10 +24,6 @@
 
 'use strict';
 
-// Most platforms don't allow reads or writes >= 2 GB.
-// See https://github.com/libuv/libuv/pull/1501.
-const kIoMaxLength = 2 ** 31 - 1;
-
 // When using FSReqCallback, make sure to create the object only *after* all
 // parameter validation has happened, so that the objects are not kept in memory
 // in case they are created but never used due to an exception.
@@ -79,6 +75,10 @@ const { FSReqCallback, statValues } = binding;
 const { toPathIfFileURL } = require('internal/url');
 const internalUtil = require('internal/util');
 const {
+  constants: {
+    kIoMaxLength,
+    kMaxUserId,
+  },
   copyObject,
   Dirent,
   getDirents,
@@ -121,8 +121,6 @@ const {
   validateInteger,
   validateInt32
 } = require('internal/validators');
-// 2 ** 32 - 1
-const kMaxUserId = 4294967295;
 
 let truncateWarn = true;
 let fs;
diff --git a/lib/internal/fs/promises.js b/lib/internal/fs/promises.js
index 767195cc2ec738..c82f8270dd9066 100644
--- a/lib/internal/fs/promises.js
+++ b/lib/internal/fs/promises.js
@@ -1,17 +1,7 @@
 'use strict';
 
-// Most platforms don't allow reads or writes >= 2 GB.
-// See https://github.com/libuv/libuv/pull/1501.
-const kIoMaxLength = 2 ** 31 - 1;
-
-// Note: This is different from kReadFileBufferLength used for non-promisified
-// fs.readFile.
-const kReadFileMaxChunkSize = 2 ** 14;
 const kWriteFileMaxChunkSize = 2 ** 14;
 
-// 2 ** 32 - 1
-const kMaxUserId = 4294967295;
-
 const {
   Error,
   MathMax,
@@ -44,6 +34,12 @@ const {
 const { isArrayBufferView } = require('internal/util/types');
 const { rimrafPromises } = require('internal/fs/rimraf');
 const {
+  constants: {
+    kIoMaxLength,
+    kMaxUserId,
+    kReadFileBufferLength,
+    kReadFileUnknownBufferLength,
+  },
   copyObject,
   getDirents,
   getOptions,
diff --git a/lib/internal/fs/read_file_context.js b/lib/internal/fs/read_file_context.js
index faca0e0c331e39..4976a7a1deb8d8 100644
--- a/lib/internal/fs/read_file_context.js
+++ b/lib/internal/fs/read_file_context.js
@@ -4,6 +4,13 @@ const {
   MathMin,
 } = primordials;
 
+const {
+  constants: {
+    kReadFileBufferLength,
+    kReadFileUnknownBufferLength,
+  }
+} = require('internal/fs/utils');
+
 const { Buffer } = require('buffer');
 
 const { FSReqCallback, close, read } = internalBinding('fs');
@@ -18,15 +25,6 @@ const lazyDOMException = hideStackFrames((message, name) => {
   return new DOMException(message, name);
 });
 
-// Use 64kb in case the file type is not a regular file and thus do not know the
-// actual file size. Increasing the value further results in more frequent over
-// allocation for small files and consumes CPU time and memory that should be
-// used else wise.
-// Use up to 512kb per read otherwise to partition reading big files to prevent
-// blocking other threads in case the available threads are all in use.
-const kReadFileUnknownBufferLength = 64 * 1024;
-const kReadFileBufferLength = 512 * 1024;
-
 function readFileAfterRead(err, bytesRead) {
   const context = this.context;
 
diff --git a/lib/internal/fs/utils.js b/lib/internal/fs/utils.js
index d3f4c621e4dd56..1d4edc0e011e4c 100644
--- a/lib/internal/fs/utils.js
+++ b/lib/internal/fs/utils.js
@@ -113,6 +113,21 @@ const kMaximumCopyMode = COPYFILE_EXCL |
                          COPYFILE_FICLONE |
                          COPYFILE_FICLONE_FORCE;
 
+// Most platforms don't allow reads or writes >= 2 GB.
+// See https://github.com/libuv/libuv/pull/1501.
+const kIoMaxLength = 2 ** 31 - 1;
+
+// Use 64kb in case the file type is not a regular file and thus do not know the
+// actual file size. Increasing the value further results in more frequent over
+// allocation for small files and consumes CPU time and memory that should be
+// used else wise.
+// Use up to 512kb per read otherwise to partition reading big files to prevent
+// blocking other threads in case the available threads are all in use.
+const kReadFileUnknownBufferLength = 64 * 1024;
+const kReadFileBufferLength = 512 * 1024;
+
+const kMaxUserId = 2 ** 32 - 1;
+
 const isWindows = process.platform === 'win32';
 
 let fs;
@@ -815,6 +830,12 @@ const validatePosition = hideStackFrames((position, name) => {
 });
 
 module.exports = {
+  constants: {
+    kIoMaxLength,
+    kMaxUserId,
+    kReadFileBufferLength,
+    kReadFileUnknownBufferLength,
+  },
   assertEncoding,
   BigIntStats,  // for testing
   copyObject,