From 57f65f27b5672f47173fa722a1080375316efd05 Mon Sep 17 00:00:00 2001
From: Momtchil Momtchev <momtchil@momtchev.com>
Date: Thu, 26 Nov 2020 12:59:00 +0100
Subject: [PATCH 1/3] stdio: implement manual start for ReadStream

All stdio ReadStream's use manual start to avoid
consuming data for example when a process
execs/spawns

Refs: https://github.com/nodejs/node/issues/36251
---
 .../bootstrap/switches/is_main_thread.js      |  6 +++-
 lib/internal/streams/readable.js              |  3 +-
 test/parallel/test-stdin-from-file-spawn.js   | 34 +++++++++++++++++++
 3 files changed, 41 insertions(+), 2 deletions(-)
 create mode 100644 test/parallel/test-stdin-from-file-spawn.js

diff --git a/lib/internal/bootstrap/switches/is_main_thread.js b/lib/internal/bootstrap/switches/is_main_thread.js
index 08623898edafac..452031e1519f41 100644
--- a/lib/internal/bootstrap/switches/is_main_thread.js
+++ b/lib/internal/bootstrap/switches/is_main_thread.js
@@ -157,7 +157,11 @@ function getStdin() {
 
     case 'FILE':
       const fs = require('fs');
-      stdin = new fs.ReadStream(null, { fd: fd, autoClose: false });
+      stdin = new fs.ReadStream(null, {
+        fd: fd,
+        autoClose: false,
+        manualStart: true
+      });
       break;
 
     case 'PIPE':
diff --git a/lib/internal/streams/readable.js b/lib/internal/streams/readable.js
index a004ce20d0aeb8..bed5aa73dde4d2 100644
--- a/lib/internal/streams/readable.js
+++ b/lib/internal/streams/readable.js
@@ -203,7 +203,8 @@ function Readable(options) {
   Stream.call(this, options);
 
   destroyImpl.construct(this, () => {
-    maybeReadMore(this, this._readableState);
+    if (!options || !options.manualStart)
+      maybeReadMore(this, this._readableState);
   });
 }
 
diff --git a/test/parallel/test-stdin-from-file-spawn.js b/test/parallel/test-stdin-from-file-spawn.js
new file mode 100644
index 00000000000000..e27018fe856f95
--- /dev/null
+++ b/test/parallel/test-stdin-from-file-spawn.js
@@ -0,0 +1,34 @@
+'use strict';
+const common = require('../common');
+const process = require('process');
+if (process.platform !== 'linux' && process.platform !== 'darwin')
+  common.skip('This is an UNIX-only test');
+
+const { execSync } = require('child_process');
+const fs = require('fs');
+const path = require('path');
+const tmpdir = require('../common/tmpdir');
+
+const tmpDir = tmpdir.path;
+tmpdir.refresh();
+const tmpCmdFile = path.join(tmpDir, 'test-stdin-from-file-spawn-cmd');
+const tmpJsFile = path.join(tmpDir, 'test-stdin-from-file-spawn.js');
+fs.writeFileSync(tmpCmdFile, 'echo hello');
+fs.writeFileSync(tmpJsFile, `
+'use strict';
+const { spawn } = require('child_process');
+// Reference the object to invoke the getter
+process.stdin;
+setTimeout(() => {
+  let ok = false;
+  const child = spawn(process.env.SHELL, [], { stdio: ['inherit', 'pipe'] });
+  child.stdout.on('data', () => {
+    ok = true;
+  });
+  child.on('close', () => {
+    process.exit(ok ? 0 : -1);
+  });
+}, 100);
+`);
+
+execSync(`${process.argv[0]} ${tmpJsFile} < ${tmpCmdFile}`);

From 33c1786a699078f7bb731f6685ea5b10a0093365 Mon Sep 17 00:00:00 2001
From: Momtchil Momtchev <momtchil@momtchev.com>
Date: Thu, 26 Nov 2020 14:40:34 +0100
Subject: [PATCH 2/3] stream: better platform compatibility

---
 test/parallel/test-stdin-from-file-spawn.js | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/test/parallel/test-stdin-from-file-spawn.js b/test/parallel/test-stdin-from-file-spawn.js
index e27018fe856f95..12c235fcfeb081 100644
--- a/test/parallel/test-stdin-from-file-spawn.js
+++ b/test/parallel/test-stdin-from-file-spawn.js
@@ -1,8 +1,15 @@
 'use strict';
 const common = require('../common');
 const process = require('process');
-if (process.platform !== 'linux' && process.platform !== 'darwin')
-  common.skip('This is an UNIX-only test');
+
+let defaultShell;
+if (process.platform === 'linux' || process.platform === 'darwin') {
+  defaultShell = '/bin/sh';
+} else if (process.platform === 'win32') {
+  defaultShell = 'cmd.exe';
+} else {
+  common.skip('This is test exists only on Linux/Win32/OSX');
+}
 
 const { execSync } = require('child_process');
 const fs = require('fs');
@@ -21,7 +28,8 @@ const { spawn } = require('child_process');
 process.stdin;
 setTimeout(() => {
   let ok = false;
-  const child = spawn(process.env.SHELL, [], { stdio: ['inherit', 'pipe'] });
+  const child = spawn(process.env.SHELL || '${defaultShell}',
+    [], { stdio: ['inherit', 'pipe'] });
   child.stdout.on('data', () => {
     ok = true;
   });

From 5cd8cb6616d789ab8f15b63284dd0da07e685440 Mon Sep 17 00:00:00 2001
From: Momtchil Momtchev <momtchil@momtchev.com>
Date: Tue, 5 Jan 2021 13:38:18 +0100
Subject: [PATCH 3/3] add an unit test with the stream API

---
 test/parallel/test-stream-manualstart.js | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
 create mode 100644 test/parallel/test-stream-manualstart.js

diff --git a/test/parallel/test-stream-manualstart.js b/test/parallel/test-stream-manualstart.js
new file mode 100644
index 00000000000000..2c7442a5538db8
--- /dev/null
+++ b/test/parallel/test-stream-manualstart.js
@@ -0,0 +1,20 @@
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+const fs = require('fs');
+
+fs.promises.open(__filename).then(common.mustCall((fd) => {
+  const rs = new fs.ReadStream(null, {
+    fd: fd,
+    manualStart: false
+  });
+  setTimeout(() => assert(rs.bytesRead > 0), common.platformTimeout(10));
+}));
+
+fs.promises.open(__filename).then(common.mustCall((fd) => {
+  const rs = new fs.ReadStream(null, {
+    fd: fd,
+    manualStart: true
+  });
+  setTimeout(() => assert(rs.bytesRead === 0), common.platformTimeout(10));
+}));