From c1920eb566838b5245733ce2d93cf79e7cba0299 Mon Sep 17 00:00:00 2001
From: Pavel Djundik <xPaw@users.noreply.github.com>
Date: Sun, 15 Dec 2019 16:56:17 +0200
Subject: [PATCH] When updating user file, write to temp file first

---
 src/clientManager.js            |  9 ++++++++-
 src/command-line/users/reset.js | 15 ++++++++++++---
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/src/clientManager.js b/src/clientManager.js
index 4e617519..4dc05385 100644
--- a/src/clientManager.js
+++ b/src/clientManager.js
@@ -195,8 +195,15 @@ ClientManager.prototype.updateUser = function(name, opts, callback) {
 		return callback ? callback() : true;
 	}
 
+	const pathReal = Helper.getUserConfigPath(name);
+	const pathTemp = pathReal + ".tmp";
+
 	try {
-		fs.writeFileSync(Helper.getUserConfigPath(name), newUser);
+		// Write to a temp file first, in case the write fails
+		// we do not lose the original file (for example when disk is full)
+		fs.writeFileSync(pathTemp, newUser);
+		fs.renameSync(pathTemp, pathReal);
+
 		return callback ? callback() : true;
 	} catch (e) {
 		log.error(`Failed to update user ${colors.green(name)} (${e})`);
diff --git a/src/command-line/users/reset.js b/src/command-line/users/reset.js
index d81a36ff..ddb550fb 100644
--- a/src/command-line/users/reset.js
+++ b/src/command-line/users/reset.js
@@ -30,8 +30,10 @@ program
 			return;
 		}
 
-		const file = Helper.getUserConfigPath(name);
-		const user = require(file);
+		const pathReal = Helper.getUserConfigPath(name);
+		const pathTemp = pathReal + ".tmp";
+		const user = JSON.parse(fs.readFileSync(pathReal, "utf-8"));
+
 		log.prompt(
 			{
 				text: "Enter new password:",
@@ -44,7 +46,14 @@ program
 
 				user.password = Helper.password.hash(password);
 				user.sessions = {};
-				fs.writeFileSync(file, JSON.stringify(user, null, "\t"));
+
+				const newUser = JSON.stringify(user, null, "\t");
+
+				// Write to a temp file first, in case the write fails
+				// we do not lose the original file (for example when disk is full)
+				fs.writeFileSync(pathTemp, newUser);
+				fs.renameSync(pathTemp, pathReal);
+
 				log.info(`Successfully reset password for ${colors.bold(name)}.`);
 			}
 		);