From 45cce8fc1c8a05108d72e3014182a237af7f66ec Mon Sep 17 00:00:00 2001
From: Colin Taylor <ctaylor7654@gmail.com>
Date: Wed, 8 Jan 2025 11:44:35 -0500
Subject: [PATCH] BUG: Fixed strict weak ordering for itkIPLFileNameList.cxx
 descend compare - Changed type of ascend and descend compare method from int
 to bool - Fixed subtraction is not comparison for both ascend and descend
 comparator - Fixed strict weak odering for descend comparator which was found
 using libc++ hardening mode in the debug setting - Changed name of ascend and
 descend comparator from qsort to remove confussion as qsort outputs -1,0,1 vs
 sort 0,1

---
 Modules/IO/IPL/src/itkIPLFileNameList.cxx | 45 ++++++++++-------------
 1 file changed, 19 insertions(+), 26 deletions(-)

diff --git a/Modules/IO/IPL/src/itkIPLFileNameList.cxx b/Modules/IO/IPL/src/itkIPLFileNameList.cxx
index c606d9041cd..d09bb9d0352 100644
--- a/Modules/IO/IPL/src/itkIPLFileNameList.cxx
+++ b/Modules/IO/IPL/src/itkIPLFileNameList.cxx
@@ -25,34 +25,31 @@ namespace itk
 struct IPLFileSortInfo_ascend_compare : public std::greater<IPLFileSortInfo *>
 {
 private:
-  int
-  qsort_IPLFileSortInfo_ascend_compar(IPLFileSortInfo * item1, IPLFileSortInfo * item2)
+  bool
+  sort_IPLFileSortInfo_ascend_compar(IPLFileSortInfo * item1, IPLFileSortInfo * item2)
   {
-    const int ImageNoDiff = item1->GetImageNumber() - item2->GetImageNumber();
 
-    if (ImageNoDiff < 0)
+    if (item1->GetImageNumber() < item2->GetImageNumber())
     {
       return true;
     }
-    if (ImageNoDiff > 0)
+    if (item1->GetImageNumber() > item2->GetImageNumber())
     {
       return false;
     }
-    const int echoNumDiff = item1->GetEchoNumber() - item2->GetEchoNumber();
-    if (echoNumDiff < 0)
+    if (item1->GetEchoNumber() < item2->GetEchoNumber())
     {
       return true;
     }
-    if (echoNumDiff > 0)
+    if (item1->GetEchoNumber() > item2->GetEchoNumber())
     {
       return false;
     }
-    const float sliceGap = item1->GetSliceLocation() - item2->GetSliceLocation();
-    if (sliceGap < 0.0)
+    if (item1->GetSliceLocation() < item2->GetSliceLocation())
     {
       return true;
     }
-    if (sliceGap > 0.0)
+    if (item1->GetSliceLocation() > item2->GetSliceLocation())
     {
       return false;
     }
@@ -63,52 +60,48 @@ struct IPLFileSortInfo_ascend_compare : public std::greater<IPLFileSortInfo *>
   bool
   operator()(IPLFileSortInfo * item1, IPLFileSortInfo * item2)
   {
-    return qsort_IPLFileSortInfo_ascend_compar(item1, item2);
+    return sort_IPLFileSortInfo_ascend_compar(item1, item2);
   }
 };
 
 struct IPLFileSortInfo_descend_compare : public std::greater<IPLFileSortInfo *>
 {
 private:
-  int
-  qsort_IPLFileSortInfo_descend_compar(IPLFileSortInfo * item1, IPLFileSortInfo * item2)
+  bool
+  sort_IPLFileSortInfo_descend_compar(IPLFileSortInfo * item1, IPLFileSortInfo * item2)
   {
-    const int ImageNoDiff = item1->GetImageNumber() - item2->GetImageNumber();
-
-    if (ImageNoDiff < 0)
+    if (item1->GetImageNumber() < item2->GetImageNumber())
     {
       return false;
     }
-    if (ImageNoDiff > 0)
+    if (item1->GetImageNumber() > item2->GetImageNumber())
     {
       return true;
     }
-    const int echoNumDiff = item1->GetEchoNumber() - item2->GetEchoNumber();
-    if (echoNumDiff < 0)
+    if (item1->GetEchoNumber() < item2->GetEchoNumber())
     {
       return false;
     }
-    if (echoNumDiff > 0)
+    if (item1->GetEchoNumber() > item2->GetEchoNumber())
     {
       return true;
     }
-    const float sliceGap = item1->GetSliceLocation() - item2->GetSliceLocation();
-    if (sliceGap < 0.0)
+    if (item1->GetSliceLocation() < item2->GetSliceLocation())
     {
       return false;
     }
-    if (sliceGap > 0.0)
+    if (item1->GetSliceLocation() > item2->GetSliceLocation())
     {
       return true;
     }
-    return (item1->GetImageFileName() >= item2->GetImageFileName());
+    return (item1->GetImageFileName() > item2->GetImageFileName());
   }
 
 public:
   bool
   operator()(IPLFileSortInfo * item1, IPLFileSortInfo * item2)
   {
-    return qsort_IPLFileSortInfo_descend_compar(item1, item2);
+    return sort_IPLFileSortInfo_descend_compar(item1, item2);
   }
 };