From b4e6584417ef0e96b86a1079cda1aaa4eb09861c Mon Sep 17 00:00:00 2001
From: Dan Stillman <dstillman@zotero.org>
Date: Sat, 13 Aug 2016 19:31:52 -0400
Subject: [PATCH] Fix PDF metadata recognition in Firefox 48

Reapplies modifications to SpecialPowers code after a0843f317

This is essentially the changes within the SpecialPowers code block from this
diff, with some modifications for the new code:

git diff 1257b17e..a0571a9a17 chrome/content/zotero/xpcom/translation/translate_firefox.js
---
 .../xpcom/translation/translate_firefox.js    | 62 +++++++++++++++----
 1 file changed, 51 insertions(+), 11 deletions(-)

diff --git a/chrome/content/zotero/xpcom/translation/translate_firefox.js b/chrome/content/zotero/xpcom/translation/translate_firefox.js
index 5efb73074..9dec02933 100644
--- a/chrome/content/zotero/xpcom/translation/translate_firefox.js
+++ b/chrome/content/zotero/xpcom/translation/translate_firefox.js
@@ -51,7 +51,7 @@ Zotero.Translate.DOMWrapper = new function() {
 	};
 	
 	function isWrapper(x) {
-		return isWrappable(x) && (typeof x.SpecialPowers_wrappedObject !== "undefined");
+		return isWrappable(x) && (typeof x.__wrappedObject !== "undefined");
 	};
 	
 	function unwrapIfWrapped(x) {
@@ -119,7 +119,7 @@ Zotero.Translate.DOMWrapper = new function() {
 		return Reflect.apply(fun, invocant, args);
 	}
 	
-	function wrapPrivileged(obj) {
+	function wrapPrivileged(obj, overrides) {
 	
 		// Primitives pass straight through.
 		if (!isWrappable(obj))
@@ -135,7 +135,7 @@ Zotero.Translate.DOMWrapper = new function() {
 		else
 			dummy = Object.create(null);
 	
-		return new Proxy(dummy, new SpecialPowersHandler(obj));
+		return new Proxy(dummy, new SpecialPowersHandler(obj, overrides));
 	};
 	
 	function unwrapPrivileged(x) {
@@ -151,13 +151,33 @@ Zotero.Translate.DOMWrapper = new function() {
 		if (!isWrapper(x))
 			throw "Trying to unwrap a non-wrapped object!";
 	
-		var obj = x.SpecialPowers_wrappedObject;
+		var obj = x.__wrappedObject;
 		// unwrapped.
 		return obj;
 	};
 	
-	function SpecialPowersHandler(wrappedObject) {
+	/*
+	 * We want to waive the __exposedProps__ security check for SpecialPowers-wrapped
+	 * objects. We do this by creating a proxy singleton that just always returns 'rw'
+	 * for any property name.
+	 */
+	function ExposedPropsWaiverHandler() {
+		// NB: XPConnect denies access if the relevant member of __exposedProps__ is not
+		// enumerable.
+		var _permit = { value: 'rw', writable: false, configurable: false, enumerable: true };
+		return {
+			getOwnPropertyDescriptor: function(name) { return _permit; },
+			ownKeys: function() { throw Error("Can't enumerate ExposedPropsWaiver"); },
+			enumerate: function() { throw Error("Can't enumerate ExposedPropsWaiver"); },
+			defineProperty: function(name) { throw Error("Can't define props on ExposedPropsWaiver"); },
+			deleteProperty: function(name) { throw Error("Can't delete props from ExposedPropsWaiver"); }
+		};
+	};
+	ExposedPropsWaiver = new Proxy({}, ExposedPropsWaiverHandler());
+	
+	function SpecialPowersHandler(wrappedObject, overrides) {
 		this.wrappedObject = wrappedObject;
+		this.overrides = overrides ? overrides: {};
 	}
 	
 	SpecialPowersHandler.prototype = {
@@ -189,22 +209,30 @@ Zotero.Translate.DOMWrapper = new function() {
 		},
 	
 		has(target, prop) {
-			if (prop === "SpecialPowers_wrappedObject")
+			if (prop === "__wrappedObject")
 				return true;
 	
+			if (this.overrides[prop] !== undefined) {
+				return true;
+			}
+			
 			return Reflect.has(this.wrappedObject, prop);
 		},
 	
 		get(target, prop, receiver) {
-			if (prop === "SpecialPowers_wrappedObject")
+			if (prop === "__wrappedObject")
 				return this.wrappedObject;
 	
+			if (prop in this.overrides) {
+				return this.overrides[prop];
+			}
+			
 			let obj = waiveXraysIfAppropriate(this.wrappedObject, prop);
 			return wrapIfUnwrapped(Reflect.get(obj, prop));
 		},
 	
 		set(target, prop, val, receiver) {
-			if (prop === "SpecialPowers_wrappedObject")
+			if (prop === "__wrappedObject")
 				return false;
 	
 			let obj = waiveXraysIfAppropriate(this.wrappedObject, prop);
@@ -212,7 +240,7 @@ Zotero.Translate.DOMWrapper = new function() {
 		},
 	
 		delete(target, prop) {
-			if (prop === "SpecialPowers_wrappedObject")
+			if (prop === "__wrappedObject")
 				return false;
 	
 			return Reflect.deleteProperty(this.wrappedObject, prop);
@@ -224,11 +252,22 @@ Zotero.Translate.DOMWrapper = new function() {
 	
 		getOwnPropertyDescriptor(target, prop) {
 			// Handle our special API.
-			if (prop === "SpecialPowers_wrappedObject") {
+			if (prop === "__wrappedObject") {
 				return { value: this.wrappedObject, writeable: true,
 								 configurable: true, enumerable: false };
 			}
+			if (name == "__wrapperOverrides") {
+				return { value: this.overrides, writeable: false, configurable: false, enumerable: false };
+			}
+			// Handle __exposedProps__.
+			if (name == "__exposedProps__") {
+				return { value: ExposedPropsWaiver, writable: false, configurable: false, enumerable: false };
+			}
 	
+			if (prop in this.overrides) {
+				return this.overrides[prop];
+			}
+			
 			let obj = waiveXraysIfAppropriate(this.wrappedObject, prop);
 			let desc = Reflect.getOwnPropertyDescriptor(obj, prop);
 	
@@ -255,10 +294,11 @@ Zotero.Translate.DOMWrapper = new function() {
 		ownKeys(target) {
 			// Insert our special API. It's not enumerable, but ownKeys()
 			// includes non-enumerable properties.
-			let props = ['SpecialPowers_wrappedObject'];
+			let props = ['__wrappedObject'];
 	
 			// Do the normal thing.
 			let flt = (a) => !props.includes(a);
+			props = props.concat(Object.keys(this.overrides).filter(flt));
 			props = props.concat(Reflect.ownKeys(this.wrappedObject).filter(flt));
 	
 			// If we've got an Xray wrapper, include the expandos as well.