From 309342748015b483a91a26a00221453ce2e13fed Mon Sep 17 00:00:00 2001
From: Yury Delendik <ydelendik@mozilla.com>
Date: Fri, 10 Aug 2012 21:31:33 -0500
Subject: [PATCH 1/2] Marks xref entries with offset 0 as free

---
 src/obj.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/obj.js b/src/obj.js
index c01ffab58..d04234f07 100644
--- a/src/obj.js
+++ b/src/obj.js
@@ -624,7 +624,7 @@ var XRef = (function XRefClosure() {
       var e = this.entries[i];
       if (e === null)
         return null;
-      return e.free ? null : e; // returns null is the entry is free
+      return e.free || !e.offset ? null : e; // returns null if entry is free
     },
     fetchIfRef: function XRef_fetchIfRef(obj) {
       if (!isRef(obj))

From b4d75ca83b1a5b74986021a21be4efc89e074f4d Mon Sep 17 00:00:00 2001
From: Yury Delendik <ydelendik@mozilla.com>
Date: Sat, 11 Aug 2012 11:57:42 -0500
Subject: [PATCH 2/2] Adds callothersubr support

---
 src/fonts.js                | 49 +++++++++++++++++++++++++++----------
 test/pdfs/issue845.pdf.link |  1 +
 test/test_manifest.json     |  7 ++++++
 3 files changed, 44 insertions(+), 13 deletions(-)
 create mode 100644 test/pdfs/issue845.pdf.link

diff --git a/src/fonts.js b/src/fonts.js
index b16c2621a..ae6d330b5 100644
--- a/src/fonts.js
+++ b/src/fonts.js
@@ -3293,6 +3293,14 @@ var Font = (function FontClosure() {
   return Font;
 })();
 
+var CallothersubrCmd = (function CallothersubrCmdClosure() {
+  function CallothersubrCmd(index) {
+    this.index = index;
+  }
+
+  return CallothersubrCmd;
+})();
+
 /*
  * Type1Parser encapsulate the needed code for parsing a Type1 font
  * program. Some of its logic depends on the Type2 charstrings
@@ -3498,6 +3506,10 @@ var Type1Parser = function type1Parser() {
               i++;
               continue;
             }
+
+            assert(argc == 0, 'callothersubr with arguments is not supported');
+            charstring.push(new CallothersubrCmd(index));
+            continue;
           } else if (escape == 17 || escape == 33) {
             // pop or setcurrentpoint commands can be ignored
             // since we are not doing callothersubr
@@ -4017,14 +4029,14 @@ Type1Font.prototype = {
   },
 
   getType2Charstrings: function Type1Font_getType2Charstrings(
-                                  type1Charstrings) {
+                                  type1Subrs) {
     var type2Charstrings = [];
-    var count = type1Charstrings.length;
-    for (var i = 0; i < count; i++) {
-      var charstring = type1Charstrings[i].charstring;
-      type2Charstrings.push(this.flattenCharstring(charstring.slice(),
-                                                   this.commandsMap));
-    }
+    var count = type1Subrs.length;
+    var type1Charstrings = [];
+    for (var i = 0; i < count; i++)
+      type1Charstrings.push(type1Subrs[i].charstring.slice());
+    for (var i = 0; i < count; i++)
+      type2Charstrings.push(this.flattenCharstring(type1Charstrings, i));
     return type2Charstrings;
   },
 
@@ -4044,11 +4056,7 @@ Type1Font.prototype = {
       type2Subrs.push([0x0B]);
 
     for (var i = 0; i < count; i++) {
-      var subr = type1Subrs[i];
-      if (!subr)
-        subr = [0x0B];
-
-      type2Subrs.push(this.flattenCharstring(subr, this.commandsMap));
+      type2Subrs.push(this.flattenCharstring(type1Subrs, i));
     }
 
     return type2Subrs;
@@ -4080,7 +4088,11 @@ Type1Font.prototype = {
     'hvcurveto': 31
   },
 
-  flattenCharstring: function Type1Font_flattenCharstring(charstring, map) {
+  flattenCharstring: function Type1Font_flattenCharstring(charstrings, index) {
+    var charstring = charstrings[index];
+    if (!charstring)
+      return [0x0B];
+    var map = this.commandsMap;
     // charstring changes size - can't cache .length in loop
     for (var i = 0; i < charstring.length; i++) {
       var command = charstring[i];
@@ -4092,6 +4104,17 @@ Type1Font.prototype = {
           charstring.splice(i++, 1, cmd[0], cmd[1]);
         else
           charstring[i] = cmd;
+      } else if (command instanceof CallothersubrCmd) {
+        var otherSubrCharstring = charstrings[command.index];
+        if (otherSubrCharstring) {
+          var lastCommand = otherSubrCharstring.indexOf('return');
+          if (lastCommand >= 0)
+            otherSubrCharstring = otherSubrCharstring.slice(0, lastCommand);
+          charstring.splice.apply(charstring,
+                                  [i, 1].concat(otherSubrCharstring));
+        } else
+          charstring.splice(i, 1); // ignoring empty subr call
+        i--;
       } else {
         // Type1 charstring use a division for number above 32000
         if (command > 32000) {
diff --git a/test/pdfs/issue845.pdf.link b/test/pdfs/issue845.pdf.link
new file mode 100644
index 000000000..b315abebb
--- /dev/null
+++ b/test/pdfs/issue845.pdf.link
@@ -0,0 +1 @@
+http://www.mediafire.com/?k8t1he9aa1pt840
diff --git a/test/test_manifest.json b/test/test_manifest.json
index 166b4fdc7..d894a97a1 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -619,6 +619,13 @@
       "link": true,
       "type": "eq"
     },
+    {  "id": "issue845",
+      "file": "pdfs/issue845.pdf",
+      "md5": "89ddf9e63cac4fa2dedcfe32a62e5407",
+      "rounds": 1,
+      "link": true,
+      "type": "eq"
+    },
     {  "id": "issue818",
       "file": "pdfs/issue818.pdf",
       "md5": "dd2f8a5bd65164ad74da2b45a6ca90cc",