3 files changed, 29 insertions, 18 deletions

diff --git a/src/dutil/apuputil.cpp b/src/dutil/apuputil.cpp
index 07d591a7..6f5825bb 100644
--- a/src/dutil/apuputil.cpp
+++ b/src/dutil/apuputil.cpp
@@ -208,7 +208,6 @@ static HRESULT ProcessEntry(
     )
 {
     HRESULT hr = S_OK;
-    BOOL fVersionFound = FALSE;
     int nCompareResult = 0;
 
     // First search the ATOM entry's custom elements to try and find the application update information.
@@ -255,25 +254,26 @@ static HRESULT ProcessEntry(
             {
                 hr = VerParseVersion(pElement->wzValue, 0, FALSE, &pApupEntry->pVersion);
                 ApupExitOnFailure(hr, "Failed to parse version string '%ls' from ATOM entry.", pElement->wzValue);
-
-                fVersionFound = TRUE;
             }
         }
     }
 
     // If there is no application identity or no version, skip the whole thing.
-    if ((!pApupEntry->wzApplicationId && !wzDefaultAppId) || !fVersionFound)
+    if ((!pApupEntry->wzApplicationId && !wzDefaultAppId) || !pApupEntry->pVersion)
     {
         ExitFunction1(hr = S_FALSE); // skip this update since it has no application id or version.
     }
 
-    hr = VerCompareParsedVersions(pApupEntry->pUpgradeVersion, pApupEntry->pVersion, &nCompareResult);
-    ApupExitOnFailure(hr, "Failed to compare version to upgrade version.");
-
-    if (nCompareResult >= 0)
+    if (pApupEntry->pUpgradeVersion)
     {
-        hr = HRESULT_FROM_WIN32(ERROR_INVALID_DATA);
-        ApupExitOnRootFailure(hr, "Upgrade version is greater than or equal to application version.");
+        hr = VerCompareParsedVersions(pApupEntry->pUpgradeVersion, pApupEntry->pVersion, &nCompareResult);
+        ApupExitOnFailure(hr, "Failed to compare version to upgrade version.");
+
+        if (nCompareResult >= 0)
+        {
+            hr = HRESULT_FROM_WIN32(ERROR_INVALID_DATA);
+            ApupExitOnRootFailure(hr, "Upgrade version is greater than or equal to application version.");
+        }
     }
 
     if (pAtomEntry->wzTitle)
@@ -443,11 +443,14 @@ static __callback int __cdecl CompareEntries(
         VerCompareParsedVersions(pEntryLeft->pUpgradeVersion, pEntryRight->pUpgradeVersion, &ret);
         if (0 == ret)
         {
-            ret = (pEntryRight->dw64TotalSize < pEntryLeft->dw64TotalSize) ? -1 :
-                  (pEntryRight->dw64TotalSize > pEntryLeft->dw64TotalSize) ?  1 : 0;
+            ret = (pEntryLeft->dw64TotalSize < pEntryRight->dw64TotalSize) ? -1 :
+                  (pEntryLeft->dw64TotalSize > pEntryRight->dw64TotalSize) ?  1 : 0;
         }
     }
 
+    // Sort descending.
+    ret = -ret;
+
     return ret;
 }
 
diff --git a/src/dutil/inc/verutil.h b/src/dutil/inc/verutil.h
index 30869aef..3caa17e1 100644
--- a/src/dutil/inc/verutil.h
+++ b/src/dutil/inc/verutil.h
@@ -34,8 +34,8 @@ typedef struct _VERUTIL_VERSION
 
 *******************************************************************/
 HRESULT DAPI VerCompareParsedVersions(
-    __in VERUTIL_VERSION* pVersion1,
-    __in VERUTIL_VERSION* pVersion2,
+    __in_opt VERUTIL_VERSION* pVersion1,
+    __in_opt VERUTIL_VERSION* pVersion2,
     __out int* pnResult
     );
 
diff --git a/src/dutil/verutil.cpp b/src/dutil/verutil.cpp
index 835dde81..fdb5a10a 100644
--- a/src/dutil/verutil.cpp
+++ b/src/dutil/verutil.cpp
@@ -40,8 +40,8 @@ static HRESULT CompareVersionSubstring(
 
 
 DAPI_(HRESULT) VerCompareParsedVersions(
-    __in VERUTIL_VERSION* pVersion1,
-    __in VERUTIL_VERSION* pVersion2,
+    __in_opt VERUTIL_VERSION* pVersion1,
+    __in_opt VERUTIL_VERSION* pVersion2,
     __out int* pnResult
     )
 {
@@ -50,8 +50,8 @@ DAPI_(HRESULT) VerCompareParsedVersions(
     DWORD cMaxReleaseLabels = 0;
     BOOL fCompareMetadata = FALSE;
 
-    if (!pVersion1 || !pVersion1->sczVersion ||
-        !pVersion2 || !pVersion2->sczVersion)
+    if (pVersion1 && !pVersion1->sczVersion ||
+        pVersion2 && !pVersion2->sczVersion)
     {
         ExitFunction1(hr = E_INVALIDARG);
     }
@@ -60,6 +60,14 @@ DAPI_(HRESULT) VerCompareParsedVersions(
     {
         ExitFunction1(nResult = 0);
     }
+    else if (pVersion1 && !pVersion2)
+    {
+        ExitFunction1(nResult = 1);
+    }
+    else if (!pVersion1 && pVersion2)
+    {
+        ExitFunction1(nResult = -1);
+    }
 
     nResult = CompareDword(pVersion1->dwMajor, pVersion2->dwMajor);
     if (0 != nResult)