CPackWIX: Allow multiple patch files and diagnose if any are missing

CPACK_WIX_PATCH_FILE now accepts a list of patch files.
An error will now be produced if any of the patch files is missing.

Previously this would be silently ignored.

Modules/CPackWIX.cmake

@@ -119,7 +119,8 @@
 #
 # .. variable:: CPACK_WIX_PATCH_FILE
 #
-#  Optional XML file with fragments to be inserted into generated WiX sources
+#  Optional list of XML files with fragments to be inserted into
+#  generated WiX sources
 #
 #  This optional variable can be used to specify an XML file that the
 #  WiX generator will use to inject fragments into its generated

Source/CPack/WiX/cmCPackWIXGenerator.cxx

@@ -242,7 +242,16 @@ bool cmCPackWIXGenerator::InitializeWiXConfiguration()
   const char* patchFilePath = GetOption("CPACK_WIX_PATCH_FILE");
   if(patchFilePath)
     {
-    this->Patch->LoadFragments(patchFilePath);
+    std::vector<std::string> patchFilePaths;
+    cmSystemTools::ExpandListArgument(patchFilePath, patchFilePaths);
+
+    for(size_t i = 0; i < patchFilePaths.size(); ++i)
+      {
+      if(!this->Patch->LoadFragments(patchFilePaths[i]))
+        {
+        return false;
+        }
+      }
     }
 
   return true;

Source/CPack/WiX/cmWIXPatch.cxx

@@ -20,10 +20,18 @@ cmWIXPatch::cmWIXPatch(cmCPackLog* logger):
 
 }
 
-void cmWIXPatch::LoadFragments(std::string const& patchFilePath)
+bool cmWIXPatch::LoadFragments(std::string const& patchFilePath)
 {
   cmWIXPatchParser parser(Fragments, Logger);
-  parser.ParseFile(patchFilePath.c_str());
+  if(!parser.ParseFile(patchFilePath.c_str()))
+    {
+    cmCPackLogger(cmCPackLog::LOG_ERROR,
+      "Failed parsing XML patch file: '" <<
+      patchFilePath << "'" << std::endl);
+    return false;
+    }
+
+  return true;
 }
 
 void cmWIXPatch::ApplyFragment(

Source/CPack/WiX/cmWIXPatch.h

@@ -26,7 +26,7 @@ class cmWIXPatch
 public:
   cmWIXPatch(cmCPackLog* logger);
 
-  void LoadFragments(std::string const& patchFilePath);
+  bool LoadFragments(std::string const& patchFilePath);
 
   void ApplyFragment(std::string const& id, cmWIXSourceWriter& writer);