lib: introduce internal/validators

Create a file to centralize argument validators that are used in
multiple internal modules.
Move validateInt32 and validateUint32 to this file.

PR-URL: #21149
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>

lib/fs.js

@@ -65,7 +65,6 @@ const internalUtil = require('internal/util');
 const {
   copyObject,
   getOptions,
-  isUint32,
   modeNum,
   nullCheck,
   preprocessSymlinkDestination,
@@ -76,16 +75,19 @@ const {
   stringToSymlinkType,
   toUnixTimestamp,
   validateBuffer,
-  validateLen,
   validateOffsetLengthRead,
   validateOffsetLengthWrite,
-  validatePath,
-  validateUint32
+  validatePath
 } = internalFS;
 const {
   CHAR_FORWARD_SLASH,
   CHAR_BACKWARD_SLASH,
 } = require('internal/constants');
+const {
+  isUint32,
+  validateInt32,
+  validateUint32
+} = require('internal/validators');
 
 // Lazy loaded
 let promises;
@@ -787,8 +789,8 @@ fs.ftruncate = function(fd, len = 0, callback) {
   // TODO(BridgeAR): This does not seem right.
   // There does not seem to be any validation before and if there is any, it
   // should work similar to validateUint32 or not have a upper cap at all.
-  // This applies to all usage of `validateLen`.
-  validateLen(len);
+  // This applies to all usage of `validateInt32(len, 'len')`.
+  validateInt32(len, 'len');
   len = Math.max(0, len);
   const req = new FSReqWrap();
   req.oncomplete = makeCallback(callback);
@@ -797,7 +799,7 @@ fs.ftruncate = function(fd, len = 0, callback) {
 
 fs.ftruncateSync = function(fd, len = 0) {
   validateUint32(fd, 'fd');
-  validateLen(len);
+  validateInt32(len, 'len');
   len = Math.max(0, len);
   const ctx = {};
   binding.ftruncate(fd, len, undefined, ctx);

lib/internal/fs/promises.js

@@ -21,20 +21,22 @@ const {
   copyObject,
   getOptions,
   getStatsFromBinding,
-  isUint32,
   modeNum,
   nullCheck,
   preprocessSymlinkDestination,
   stringToFlags,
   stringToSymlinkType,
   toUnixTimestamp,
   validateBuffer,
-  validateLen,
   validateOffsetLengthRead,
   validateOffsetLengthWrite,
-  validatePath,
-  validateUint32
+  validatePath
 } = require('internal/fs/utils');
+const {
+  isUint32,
+  validateInt32,
+  validateUint32
+} = require('internal/validators');
 const pathModule = require('path');
 
 const kHandle = Symbol('handle');
@@ -263,7 +265,7 @@ async function truncate(path, len = 0) {
 
 async function ftruncate(handle, len = 0) {
   validateFileHandle(handle);
-  validateLen(len);
+  validateInt32(len, 'len');
   len = Math.max(0, len);
   return binding.ftruncate(handle.fd, len, kUsePromises);
 }

lib/internal/fs/utils.js

@@ -70,9 +70,6 @@ function getOptions(options, defaultOptions) {
   return options;
 }
 
-function isInt32(n) { return n === (n | 0); }
-function isUint32(n) { return n === (n >>> 0); }
-
 function modeNum(m, def) {
   if (typeof m === 'number')
     return m;
@@ -341,26 +338,6 @@ function validateBuffer(buffer) {
   }
 }
 
-function validateLen(len) {
-  let err;
-
-  if (!isInt32(len)) {
-    if (typeof len !== 'number') {
-      err = new ERR_INVALID_ARG_TYPE('len', 'number', len);
-    } else if (!Number.isInteger(len)) {
-      err = new ERR_OUT_OF_RANGE('len', 'an integer', len);
-    } else {
-      // 2 ** 31 === 2147483648
-      err = new ERR_OUT_OF_RANGE('len', '> -2147483649 && < 2147483648', len);
-    }
-  }
-
-  if (err !== undefined) {
-    Error.captureStackTrace(err, validateLen);
-    throw err;
-  }
-}
-
 function validateOffsetLengthRead(offset, length, bufferLength) {
   let err;
 
@@ -410,28 +387,10 @@ function validatePath(path, propName = 'path') {
   }
 }
 
-function validateUint32(value, propName) {
-  if (!isUint32(value)) {
-    let err;
-    if (typeof value !== 'number') {
-      err = new ERR_INVALID_ARG_TYPE(propName, 'number', value);
-    } else if (!Number.isInteger(value)) {
-      err = new ERR_OUT_OF_RANGE(propName, 'an integer', value);
-    } else {
-      // 2 ** 32 === 4294967296
-      err = new ERR_OUT_OF_RANGE(propName, '>= 0 && < 4294967296', value);
-    }
-    Error.captureStackTrace(err, validateUint32);
-    throw err;
-  }
-}
-
 module.exports = {
   assertEncoding,
   copyObject,
   getOptions,
-  isInt32,
-  isUint32,
   modeNum,
   nullCheck,
   preprocessSymlinkDestination,
@@ -443,9 +402,7 @@ module.exports = {
   SyncWriteStream,
   toUnixTimestamp,
   validateBuffer,
-  validateLen,
   validateOffsetLengthRead,
   validateOffsetLengthWrite,
-  validatePath,
-  validateUint32
+  validatePath
 };

lib/internal/validators.js

@@ -0,0 +1,58 @@
+'use strict';
+
+const {
+  ERR_INVALID_ARG_TYPE,
+  ERR_OUT_OF_RANGE
+} = require('internal/errors').codes;
+
+function isInt32(value) {
+  return value === (value | 0);
+}
+
+function isUint32(value) {
+  return value === (value >>> 0);
+}
+
+function validateInt32(value, name) {
+  if (!isInt32(value)) {
+    let err;
+    if (typeof value !== 'number') {
+      err = new ERR_INVALID_ARG_TYPE(name, 'number', value);
+    } else if (!Number.isInteger(value)) {
+      err = new ERR_OUT_OF_RANGE(name, 'an integer', value);
+    } else {
+      // 2 ** 31 === 2147483648
+      err = new ERR_OUT_OF_RANGE(name, '> -2147483649 && < 2147483648', value);
+    }
+    Error.captureStackTrace(err, validateInt32);
+    throw err;
+  }
+}
+
+function validateUint32(value, name, positive) {
+  if (!isUint32(value)) {
+    let err;
+    if (typeof value !== 'number') {
+      err = new ERR_INVALID_ARG_TYPE(name, 'number', value);
+    } else if (!Number.isInteger(value)) {
+      err = new ERR_OUT_OF_RANGE(name, 'an integer', value);
+    } else {
+      const min = positive ? 1 : 0;
+      // 2 ** 32 === 4294967296
+      err = new ERR_OUT_OF_RANGE(name, `>= ${min} && < 4294967296`, value);
+    }
+    Error.captureStackTrace(err, validateUint32);
+    throw err;
+  } else if (positive && value === 0) {
+    const err = new ERR_OUT_OF_RANGE(name, '>= 1 && < 4294967296', value);
+    Error.captureStackTrace(err, validateUint32);
+    throw err;
+  }
+}
+
+module.exports = {
+  isInt32,
+  isUint32,
+  validateInt32,
+  validateUint32
+};

node.gyp

@@ -147,6 +147,7 @@
       'lib/internal/http2/util.js',
       'lib/internal/v8_prof_polyfill.js',
       'lib/internal/v8_prof_processor.js',
+      'lib/internal/validators.js',
       'lib/internal/stream_base_commons.js',
       'lib/internal/vm/module.js',
       'lib/internal/streams/lazy_transform.js',