From 80d318f51a2f06023f27e39662171882a2b34f45 Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim@planet.com>
Date: Mon, 31 Aug 2020 23:38:03 -0600
Subject: [PATCH] Represent stdin, stdout, and stderr as files

---
 lib/binding.js | 14 +++++++++++-
 lib/file.js    | 58 +++++++++++++++++++++++++++++++++++++++++++++++++-
 lib/item.js    | 13 ++++++-----
 3 files changed, 76 insertions(+), 9 deletions(-)

diff --git a/lib/binding.js b/lib/binding.js
index 0f70343c..13fe83f0 100644
--- a/lib/binding.js
+++ b/lib/binding.js
@@ -268,7 +268,19 @@ function Binding(system) {
    * Counter for file descriptors.
    * @type {number}
    */
-  this._counter = 0;
+  this._counter = -1;
+
+  const stdin = new FileDescriptor(constants.O_RDWR);
+  stdin.setItem(new File.StandardInput());
+  this.trackDescriptor(stdin);
+
+  const stdout = new FileDescriptor(constants.O_RDWR);
+  stdout.setItem(new File.StandardOutput());
+  this.trackDescriptor(stdout);
+
+  const stderr = new FileDescriptor(constants.O_RDWR);
+  stderr.setItem(new File.StandardError());
+  this.trackDescriptor(stderr);
 }
 
 /**
diff --git a/lib/file.js b/lib/file.js
index 3edef1c7..fc1df181 100644
--- a/lib/file.js
+++ b/lib/file.js
@@ -10,7 +10,7 @@ const EMPTY = bufferAlloc(0);
 const constants = require('constants');
 
 /**
- * A directory.
+ * A file.
  * @constructor
  */
 function File() {
@@ -67,3 +67,59 @@ File.prototype.getStats = function() {
  * @type {function()}
  */
 exports = module.exports = File;
+
+/**
+ * Standard input.
+ * @constructor
+ */
+function StandardInput() {
+  File.call(this);
+  this.setMode(438); // 0666
+}
+util.inherits(StandardInput, File);
+
+exports.StandardInput = StandardInput;
+
+/**
+ * Standard output.
+ * @constructor
+ */
+function StandardOutput() {
+  File.call(this);
+  this.setMode(438); // 0666
+}
+util.inherits(StandardOutput, File);
+
+/**
+ * Write the contents to stdout.
+ * @param {string|Buffer} content File contents.
+ */
+StandardOutput.prototype.setContent = function(content) {
+  if (process.stdout.isTTY) {
+    process.stdout.write(content);
+  }
+};
+
+exports.StandardOutput = StandardOutput;
+
+/**
+ * Standard error.
+ * @constructor
+ */
+function StandardError() {
+  File.call(this);
+  this.setMode(438); // 0666
+}
+util.inherits(StandardError, File);
+
+/**
+ * Write the contents to stderr.
+ * @param {string|Buffer} content File contents.
+ */
+StandardError.prototype.setContent = function(content) {
+  if (process.stderr.isTTY) {
+    process.stderr.write(content);
+  }
+};
+
+exports.StandardError = StandardError;
diff --git a/lib/item.js b/lib/item.js
index 1ec3e75d..dcbd464a 100644
--- a/lib/item.js
+++ b/lib/item.js
@@ -92,14 +92,13 @@ function Item() {
  * Add execute if read allowed
  * See notes in index.js -> mapping#addDir
  */
-// prettier-ignore
 Item.fixWin32Permissions = mode =>
-  (process.platform !== 'win32')
-  ? mode
-  : mode |
-      ((mode & permissions.USER_READ) && permissions.USER_EXEC) |
-      ((mode & permissions.GROUP_READ) && permissions.GROUP_EXEC) |
-      ((mode & permissions.OTHER_READ) && permissions.OTHER_EXEC);
+  process.platform !== 'win32'
+    ? mode
+    : mode |
+      (mode & permissions.USER_READ && permissions.USER_EXEC) |
+      (mode & permissions.GROUP_READ && permissions.GROUP_EXEC) |
+      (mode & permissions.OTHER_READ && permissions.OTHER_EXEC);
 
 /**
  * Determine if the current user has read permission.