child_process: support Uint8Array input to methods

Support `Uint8Array` input to all the synchronous methods.

PR-URL: #10653
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michal Zasso <targos@protonmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>

Author: addaleax

doc/api/child_process.md

@@ -580,8 +580,8 @@ added: v0.11.12
 * `args` {Array} List of string arguments
 * `options` {Object}
   * `cwd` {String} Current working directory of the child process
-  * `input` {String|Buffer} The value which will be passed as stdin to the
-    spawned process
+  * `input` {String|Buffer|Uint8Array} The value which will be passed as stdin
+    to the spawned process
     - supplying this value will override `stdio[0]`
   * `stdio` {String | Array} Child's stdio configuration. (Default: `'pipe'`)
     - `stderr` by default will be output to the parent process' stderr unless
@@ -618,8 +618,8 @@ added: v0.11.12
 * `command` {String} The command to run
 * `options` {Object}
   * `cwd` {String} Current working directory of the child process
-  * `input` {String|Buffer} The value which will be passed as stdin to the
-    spawned process
+  * `input` {String|Buffer|Uint8Array} The value which will be passed as stdin
+    to the spawned process
     - supplying this value will override `stdio[0]`
   * `stdio` {String | Array} Child's stdio configuration. (Default: `'pipe'`)
     - `stderr` by default will be output to the parent process' stderr unless
@@ -666,8 +666,8 @@ added: v0.11.12
 * `args` {Array} List of string arguments
 * `options` {Object}
   * `cwd` {String} Current working directory of the child process
-  * `input` {String|Buffer} The value which will be passed as stdin to the
-    spawned process
+  * `input` {String|Buffer|Uint8Array} The value which will be passed as stdin
+    to the spawned process
     - supplying this value will override `stdio[0]`
   * `stdio` {String | Array} Child's stdio configuration.
   * `env` {Object} Environment key-value pairs

lib/child_process.js

@@ -9,6 +9,7 @@ const uv = process.binding('uv');
 const spawn_sync = process.binding('spawn_sync');
 const Buffer = require('buffer').Buffer;
 const Pipe = process.binding('pipe_wrap').Pipe;
+const { isUint8Array } = process.binding('util');
 const child_process = require('internal/child_process');
 
 const errnoException = util._errnoException;
@@ -503,13 +504,13 @@ function spawnSync(/*file, args, options*/) {
     var input = options.stdio[i] && options.stdio[i].input;
     if (input != null) {
       var pipe = options.stdio[i] = util._extend({}, options.stdio[i]);
-      if (Buffer.isBuffer(input))
+      if (isUint8Array(input))
         pipe.input = input;
       else if (typeof input === 'string')
         pipe.input = Buffer.from(input, options.encoding);
       else
         throw new TypeError(util.format(
-            'stdio[%d] should be Buffer or string not %s',
+            'stdio[%d] should be Buffer, Uint8Array or string not %s',
             i,
             typeof input));
     }

lib/internal/child_process.js

@@ -1,7 +1,6 @@
 'use strict';
 
 const StringDecoder = require('string_decoder').StringDecoder;
-const Buffer = require('buffer').Buffer;
 const EventEmitter = require('events');
 const net = require('net');
 const dgram = require('dgram');
@@ -17,6 +16,7 @@ const TTY = process.binding('tty_wrap').TTY;
 const TCP = process.binding('tcp_wrap').TCP;
 const UDP = process.binding('udp_wrap').UDP;
 const SocketList = require('internal/socket_list');
+const { isUint8Array } = process.binding('util');
 
 const errnoException = util._errnoException;
 const SocketListSend = SocketList.SocketListSend;
@@ -847,10 +847,11 @@ function _validateStdio(stdio, sync) {
         wrapType: getHandleWrapType(handle),
         handle: handle
       });
-    } else if (stdio instanceof Buffer || typeof stdio === 'string') {
+    } else if (isUint8Array(stdio) || typeof stdio === 'string') {
       if (!sync) {
         cleanup();
-        throw new TypeError('Asynchronous forks do not support Buffer input: ' +
+        throw new TypeError('Asynchronous forks do not support ' +
+                            'Buffer, Uint8Array or string input: ' +
             util.inspect(stdio));
       }
     } else {

test/parallel/test-child-process-spawnsync-input.js

@@ -57,7 +57,7 @@ var options = {
 
 assert.throws(function() {
   spawnSync('cat', [], options);
-}, /TypeError:.*should be Buffer or string not number/);
+}, /TypeError:.*should be Buffer, Uint8Array or string not number/);
 
 
 options = {
@@ -80,6 +80,16 @@ checkSpawnSyncRet(ret);
 assert.deepStrictEqual(ret.stdout, options.input);
 assert.deepStrictEqual(ret.stderr, Buffer.from(''));
 
+options = {
+  input: Uint8Array.from(Buffer.from('hello world'))
+};
+
+ret = spawnSync('cat', [], options);
+
+checkSpawnSyncRet(ret);
+assert.deepStrictEqual(ret.stdout, options.input);
+assert.deepStrictEqual(ret.stderr, Buffer.from(''));
+
 verifyBufOutput(spawnSync(process.execPath, args));
 
 ret = spawnSync(process.execPath, args, { encoding: 'utf8' });