From c830021b078a92448d4f7dc8281bfcec1e2873be Mon Sep 17 00:00:00 2001
From: Yury Delendik <ydelendik@mozilla.com>
Date: Fri, 7 Jul 2017 15:12:52 -0500
Subject: [PATCH] Fixes CFF data glyph widths

---
 src/core/cff_parser.js       | 31 ++++++++++++++++++-------------
 test/unit/cff_parser_spec.js | 27 +++++++++++++++++++++++----
 2 files changed, 41 insertions(+), 17 deletions(-)

diff --git a/src/core/cff_parser.js b/src/core/cff_parser.js
index f0c1e3749..2c044131f 100644
--- a/src/core/cff_parser.js
+++ b/src/core/cff_parser.js
@@ -268,12 +268,14 @@ var CFFParser = (function CFFParserClosure() {
       cff.charset = charset;
       cff.encoding = encoding;
 
-      var charStringsAndSeacs = this.parseCharStrings(
-                                  charStringIndex,
-                                  topDict.privateDict.subrsIndex,
-                                  globalSubrIndex.obj,
-                                  cff.fdSelect,
-                                  cff.fdArray);
+      var charStringsAndSeacs = this.parseCharStrings({
+        charStrings: charStringIndex,
+        localSubrIndex: topDict.privateDict.subrsIndex,
+        globalSubrIndex: globalSubrIndex.obj,
+        fdSelect: cff.fdSelect,
+        fdArray: cff.fdArray,
+        privateDict: topDict.privateDict,
+      });
       cff.charStrings = charStringsAndSeacs.charStrings;
       cff.seacs = charStringsAndSeacs.seacs;
       cff.widths = charStringsAndSeacs.widths;
@@ -601,11 +603,8 @@ var CFFParser = (function CFFParserClosure() {
       state.stackSize = stackSize;
       return true;
     },
-    parseCharStrings: function CFFParser_parseCharStrings(charStrings,
-                                                          localSubrIndex,
-                                                          globalSubrIndex,
-                                                          fdSelect,
-                                                          fdArray) {
+    parseCharStrings({ charStrings, localSubrIndex, globalSubrIndex, fdSelect,
+                       fdArray, privateDict, }) {
       var seacs = [];
       var widths = [];
       var count = charStrings.count;
@@ -623,6 +622,7 @@ var CFFParser = (function CFFParserClosure() {
         };
         var valid = true;
         var localSubrToUse = null;
+        var privateDictToUse = privateDict;
         if (fdSelect && fdArray.length) {
           var fdIndex = fdSelect.getFDIndex(i);
           if (fdIndex === -1) {
@@ -634,7 +634,8 @@ var CFFParser = (function CFFParserClosure() {
             valid = false;
           }
           if (valid) {
-            localSubrToUse = fdArray[fdIndex].privateDict.subrsIndex;
+            privateDictToUse = fdArray[fdIndex].privateDict;
+            localSubrToUse = privateDictToUse.subrsIndex;
           }
         } else if (localSubrIndex) {
           localSubrToUse = localSubrIndex;
@@ -644,7 +645,11 @@ var CFFParser = (function CFFParserClosure() {
                                        globalSubrIndex);
         }
         if (state.width !== null) {
-          widths[i] = state.width;
+          const nominalWidth = privateDictToUse.getByName('nominalWidthX');
+          widths[i] = nominalWidth + state.width;
+        } else {
+          const defaultWidth = privateDictToUse.getByName('defaultWidthX');
+          widths[i] = defaultWidth;
         }
         if (state.seac !== null) {
           seacs[i] = state.seac;
diff --git a/test/unit/cff_parser_spec.js b/test/unit/cff_parser_spec.js
index 7df4bc113..ee5b8fcbe 100644
--- a/test/unit/cff_parser_spec.js
+++ b/test/unit/cff_parser_spec.js
@@ -28,6 +28,13 @@ describe('CFFParser', function() {
     return result;
   }
 
+  // Stub that returns `0` for any privateDict key.
+  var privateDictStub = {
+    getByName(name) {
+      return 0;
+    },
+  };
+
   var fontData, parser, cff;
 
   beforeAll(function (done) {
@@ -163,7 +170,10 @@ describe('CFFParser', function() {
                               ]);
     parser.bytes = bytes;
     var charStringsIndex = parser.parseIndex(0).obj;
-    var charStrings = parser.parseCharStrings(charStringsIndex).charStrings;
+    var charStrings = parser.parseCharStrings({
+      charStrings: charStringsIndex,
+      privateDict: privateDictStub,
+    }).charStrings;
     expect(charStrings.count).toEqual(1);
     // shoudn't be sanitized
     expect(charStrings.get(0).length).toEqual(38);
@@ -180,7 +190,10 @@ describe('CFFParser', function() {
                                 237, 247, 22, 247, 72, 204, 247, 86, 14]);
     parser.bytes = bytes;
     var charStringsIndex = parser.parseIndex(0).obj;
-    var result = parser.parseCharStrings(charStringsIndex);
+    var result = parser.parseCharStrings({
+      charStrings: charStringsIndex,
+      privateDict: privateDictStub,
+    });
     expect(result.charStrings.count).toEqual(1);
     expect(result.charStrings.get(0).length).toEqual(1);
     expect(result.seacs.length).toEqual(1);
@@ -202,7 +215,10 @@ describe('CFFParser', function() {
                                 237, 247, 22, 247, 72, 204, 247, 86, 14]);
     parser.bytes = bytes;
     var charStringsIndex = parser.parseIndex(0).obj;
-    var result = parser.parseCharStrings(charStringsIndex);
+    var result = parser.parseCharStrings({
+      charStrings: charStringsIndex,
+      privateDict: privateDictStub,
+    });
     expect(result.charStrings.count).toEqual(1);
     expect(result.charStrings.get(0).length).toEqual(9);
     expect(result.seacs.length).toEqual(0);
@@ -215,7 +231,10 @@ describe('CFFParser', function() {
                                 14]);
     parser.bytes = bytes;
     var charStringsIndex = parser.parseIndex(0).obj;
-    var result = parser.parseCharStrings(charStringsIndex);
+    var result = parser.parseCharStrings({
+      charStrings: charStringsIndex,
+      privateDict: privateDictStub,
+    });
     expect(result.charStrings.count).toEqual(1);
     expect(result.charStrings.get(0)[0]).toEqual(14);
     expect(result.seacs.length).toEqual(0);