From 62734b24c29a9eb7c262e3a7a0445bdb89bce3cc Mon Sep 17 00:00:00 2001
From: Jakub Kucharski <jakubkucharski97@gmail.com>
Date: Tue, 23 Feb 2016 15:36:43 +0100
Subject: [PATCH 1/7] Added XRef modification flag

---
 poppler/PDFDoc.cc | 12 +-----------
 poppler/XRef.cc   |  5 +++++
 poppler/XRef.h    |  7 +++++++
 3 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/poppler/PDFDoc.cc b/poppler/PDFDoc.cc
index 9fc43e5..703a4fd 100644
--- a/poppler/PDFDoc.cc
+++ b/poppler/PDFDoc.cc
@@ -865,17 +865,7 @@ int PDFDoc::saveAs(GooString *name, PDFWriteMode mode) {
 }
 
 int PDFDoc::saveAs(OutStream *outStr, PDFWriteMode mode) {
-
-  // find if we have updated objects
-  GBool updated = gFalse;
-  for(int i=0; i<xref->getNumObjects(); i++) {
-    if (xref->getEntry(i)->getFlag(XRefEntry::Updated)) {
-      updated = gTrue;
-      break;
-    }
-  }
-
-  if (!updated && mode == writeStandard) {
+  if (!xref->isModified() && mode == writeStandard) {
     // simply copy the original file
     saveWithoutChangesAs (outStr);
   } else if (mode == writeForceRewrite) {
diff --git a/poppler/XRef.cc b/poppler/XRef.cc
index 3d032bc..8570819 100644
--- a/poppler/XRef.cc
+++ b/poppler/XRef.cc
@@ -24,6 +24,7 @@
 // Copyright (C) 2012, 2013 Fabio D'Urso <fabiodurso@hotmail.it>
 // Copyright (C) 2013, 2014 Adrian Johnson <ajohnson@redneon.com>
 // Copyright (C) 2013 Pino Toscano <pino@kde.org>
+// Copyright (C) 2016 Jakub Kucharski <jakubkucharski97@gmail.com>
 //
 // To see a description of the changes please see the Changelog file that
 // came with your tarball or type make ChangeLog if you are building from git
@@ -286,6 +287,7 @@ void XRef::init() {
   entries = NULL;
   capacity = 0;
   size = 0;
+  modified = gFalse;
   streamEnds = NULL;
   streamEndsLen = 0;
   objStrs = new PopplerCache(5);
@@ -1373,6 +1375,7 @@ void XRef::setModifiedObject (Object* o, Ref r) {
   e->obj.free();
   o->copy(&(e->obj));
   e->setFlag(XRefEntry::Updated, gTrue);
+  setModified();
 }
 
 Ref XRef::addIndirectObject (Object* o) {
@@ -1398,6 +1401,7 @@ Ref XRef::addIndirectObject (Object* o) {
   e->type = xrefEntryUncompressed;
   o->copy(&e->obj);
   e->setFlag(XRefEntry::Updated, gTrue);
+  setModified();
 
   Ref r;
   r.num = entryIndexToUse;
@@ -1419,6 +1423,7 @@ void XRef::removeIndirectObject(Ref r) {
   e->type = xrefEntryFree;
   e->gen++;
   e->setFlag(XRefEntry::Updated, gTrue);
+  setModified();
 }
 
 void XRef::writeXRef(XRef::XRefWriter *writer, GBool writeAllEntries) {
diff --git a/poppler/XRef.h b/poppler/XRef.h
index 8748cb4..739b537 100644
--- a/poppler/XRef.h
+++ b/poppler/XRef.h
@@ -22,6 +22,7 @@
 // Copyright (C) 2012, 2013, 2016 Thomas Freitag <Thomas.Freitag@kabelmail.de>
 // Copyright (C) 2012, 2013 Fabio D'Urso <fabiodurso@hotmail.it>
 // Copyright (C) 2013 Adrian Johnson <ajohnson@redneon.com>
+// Copyright (C) 2016 Jakub Kucharski <jakubkucharski97@gmail.com>
 //
 // To see a description of the changes please see the Changelog file that
 // came with your tarball or type make ChangeLog if you are building from git
@@ -175,6 +176,11 @@ public:
   XRefEntry *getEntry(int i, GBool complainIfMissing = gTrue);
   Object *getTrailerDict() { return &trailerDict; }
 
+  // Was the XRef modified?
+  GBool isModified() { return modified; }
+  // Set the modification flag for XRef to true.
+  void setModified() { modified = gTrue; }
+
   // Write access
   void setModifiedObject(Object* o, Ref r);
   Ref addIndirectObject (Object* o);
@@ -203,6 +209,7 @@ private:
   int errCode;			// error code (if <ok> is false)
   GBool xrefReconstructed;	// marker, true if xref was already reconstructed
   Object trailerDict;		// trailer dictionary
+  GBool modified;
   Goffset *streamEnds;		// 'endstream' positions - only used in
 				//   damaged files
   int streamEndsLen;		// number of valid entries in streamEnds
-- 
2.8.3