ofz#6469 ensure coords are in correct order

I.e., xs <= xe and ys <= ye. The previous situation could lead to
surprises like negative width/height.

Change-Id: I23fc2786292d9eebe713870a69e577c9324da09f

5 files changed, 50 insertions, 5 deletions

diff --git a/src/lib/Coordinate.cpp b/src/lib/Coordinate.cpp
new file mode 100644
index 0000000..b865632
--- /dev/null
+++ b/src/lib/Coordinate.cpp
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/*
+ * This file is part of the libmspub project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include "Coordinate.h"
+
+#include <utility>
+
+namespace libmspub
+{
+
+Coordinate::Coordinate(int xs, int ys, int xe, int ye)
+  : m_xs(xs)
+  , m_ys(ys)
+  , m_xe(xe)
+  , m_ye(ye)
+{
+  arrange();
+}
+
+void Coordinate::arrange()
+{
+  if (m_xs > m_xe)
+    std::swap(m_xs, m_xe);
+  if (m_ys > m_ye)
+    std::swap(m_ys, m_ye);
+}
+
+}
+
+/* vim:set shiftwidth=2 softtabstop=2 expandtab: */
diff --git a/src/lib/Coordinate.h b/src/lib/Coordinate.h
index bec3fe2..4471f86 100644
--- a/src/lib/Coordinate.h
+++ b/src/lib/Coordinate.h
@@ -10,14 +10,17 @@
 #ifndef INCLUDED_COORDINATE_H
 #define INCLUDED_COORDINATE_H
 
+#include <boost/cstdint.hpp>
+
 #include "MSPUBConstants.h"
 
 namespace libmspub
 {
 struct Coordinate
 {
-  Coordinate(int xs, int ys, int xe, int ye) : m_xs(xs), m_ys(ys), m_xe(xe), m_ye(ye) { }
+  Coordinate(int xs, int ys, int xe, int ye);
   Coordinate() : m_xs(0), m_ys(0), m_xe(0), m_ye(0) { }
+  void arrange();
   int m_xs, m_ys, m_xe, m_ye;
   double getXIn(double pageWidth) const
   {
diff --git a/src/lib/MSPUBCollector.cpp b/src/lib/MSPUBCollector.cpp
index c050930..a2efb2c 100644
--- a/src/lib/MSPUBCollector.cpp
+++ b/src/lib/MSPUBCollector.cpp
@@ -459,10 +459,14 @@ Coordinate getFudgedCoordinates(Coordinate coord, const std::vector<Line> &lines
   }
   else
   {
-    fudged.m_xs += leftFudge;
-    fudged.m_xe -= rightFudge;
-    fudged.m_ys += topFudge;
-    fudged.m_ye -= bottomFudge;
+    if (unsigned(fudged.m_xe - fudged.m_xs) > leftFudge)
+      fudged.m_xs += leftFudge;
+    if (unsigned(fudged.m_xe - fudged.m_xs) > rightFudge)
+      fudged.m_xe -= rightFudge;
+    if (unsigned(fudged.m_ye - fudged.m_ys) > topFudge)
+      fudged.m_ys += topFudge;
+    if (unsigned(fudged.m_ye - fudged.m_ys) > bottomFudge)
+      fudged.m_ye -= bottomFudge;
   }
   return fudged;
 }
diff --git a/src/lib/MSPUBParser.cpp b/src/lib/MSPUBParser.cpp
index 883cf67..b13bb47 100644
--- a/src/lib/MSPUBParser.cpp
+++ b/src/lib/MSPUBParser.cpp
@@ -1622,6 +1622,7 @@ void MSPUBParser::parseEscherShape(librevenge::RVNGInputStream *input, const Esc
     parentCoordinateSystem.m_ys = readU32(input);
     parentCoordinateSystem.m_xe = readU32(input);
     parentCoordinateSystem.m_ye = readU32(input);
+    parentCoordinateSystem.arrange();
     definesRelativeCoordinates = true;
   }
   input->seek(sp.contentsOffset, librevenge::RVNG_SEEK_SET);
diff --git a/src/lib/Makefile.am b/src/lib/Makefile.am
index 2573363..bd8a68a 100644
--- a/src/lib/Makefile.am
+++ b/src/lib/Makefile.am
@@ -16,6 +16,7 @@ libmspub_@MSPUB_MAJOR_VERSION@_@MSPUB_MINOR_VERSION@_la_SOURCES = \
 	BorderArtInfo.h \
 	ColorReference.cpp \
 	ColorReference.h \
+	Coordinate.cpp \
 	Coordinate.h \
 	Dash.cpp \
 	Dash.h \