From 89840649d9fb79862e0b9d9d9971a2b4a4bf8a24 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Fri, 19 Aug 2022 17:35:49 +0200
Subject: [PATCH] Ensure that we don't try to re-open, or update the
 password-callback, when the password dialog is already open

Currently in `disableWorker=true` mode it's possible that opening of password-protected PDF documents outright fails, if an *incorrect* password is entered. Apparently the event ordering is subtly different in the non-Worker case, which causes the password-callback to be updated *before* the dialog has been fully closed.
To avoid that we'll utilize a `PromiseCapability` to keep track of the state of the password dialog, such that we can delay both re-opening and (importantly) updating of the password-callback until doing so is safe.

This patch *may* also fix issue 15330, but it's impossible for me to tell.
---
 web/password_prompt.js | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/web/password_prompt.js b/web/password_prompt.js
index 2207b1a9d..891e65fb1 100644
--- a/web/password_prompt.js
+++ b/web/password_prompt.js
@@ -13,7 +13,7 @@
  * limitations under the License.
  */
 
-import { PasswordResponses } from "pdfjs-lib";
+import { createPromiseCapability, PasswordResponses } from "pdfjs-lib";
 
 /**
  * @typedef {Object} PasswordPromptOptions
@@ -28,6 +28,8 @@ import { PasswordResponses } from "pdfjs-lib";
  */
 
 class PasswordPrompt {
+  #activeCapability = null;
+
   #updateCallback = null;
 
   #reason = null;
@@ -64,7 +66,17 @@ class PasswordPrompt {
   }
 
   async open() {
-    await this.overlayManager.open(this.dialog);
+    if (this.#activeCapability) {
+      await this.#activeCapability.promise;
+    }
+    this.#activeCapability = createPromiseCapability();
+
+    try {
+      await this.overlayManager.open(this.dialog);
+    } catch (ex) {
+      this.#activeCapability = null;
+      throw ex;
+    }
 
     const passwordIncorrect =
       this.#reason === PasswordResponses.INCORRECT_PASSWORD;
@@ -92,6 +104,7 @@ class PasswordPrompt {
 
   #cancel() {
     this.#invokeCallback(new Error("PasswordPrompt cancelled."));
+    this.#activeCapability.resolve();
   }
 
   #invokeCallback(password) {
@@ -105,7 +118,10 @@ class PasswordPrompt {
     this.#updateCallback = null;
   }
 
-  setUpdateCallback(updateCallback, reason) {
+  async setUpdateCallback(updateCallback, reason) {
+    if (this.#activeCapability) {
+      await this.#activeCapability.promise;
+    }
     this.#updateCallback = updateCallback;
     this.#reason = reason;
   }