CPackWIX: Implement new CPACK_WIX_SKIP_PROGRAM_FOLDER feature

The new variable allows setting of a custom absolute installation prefix
outside of the ProgramFiles folders.

Help/release/dev/wix-custom-install-dir.rst

+wix-custom-install-dir
+----------------------
+
+* The CPack WIX generator now supports
+  :variable:`CPACK_WIX_SKIP_PROGRAM_FOLDER` to allow specification
+  of a custom absolute installation prefix outside
+  of the ProgramFiles folders.

Modules/CPackWIX.cmake

@@ -248,6 +248,23 @@
 # Sets the description of the root install feature in the WIX installer. Same as
 # CPACK_COMPONENT_<compName>_DESCRIPTION for components.
 #
+# .. variable:: CPACK_WIX_SKIP_PROGRAM_FOLDER
+#
+# If this variable is set to true, the default install location
+# of the generated package will be CPACK_PACKAGE_INSTALL_DIRECTORY directly.
+# The install location will not be located relatively below
+# ProgramFiles or ProgramFiles64.
+#
+#   .. note::
+#     Installers created with this feature do not take differences
+#     between the system on which the installer is created
+#     and the system on which the installer might be used into account.
+#
+#     It is therefor possible that the installer e.g. might try to install
+#     onto a drive that is unavailable or unintended or a path that does not
+#     follow the localization or convention of the system on which the
+#     installation is performed.
+#
 
 #=============================================================================
 # Copyright 2014-2015 Kitware, Inc.

Source/CPack/WiX/cmCPackWIXGenerator.cxx

@@ -18,6 +18,7 @@
 #include <cmGeneratedFileStream.h>
 #include <cmInstalledFile.h>
 #include <cmSystemTools.h>
+#include <cmUuid.h>
 
 #include "cmWIXDirectoriesSourceWriter.h"
 #include "cmWIXFeaturesSourceWriter.h"
@@ -441,6 +442,11 @@ bool cmCPackWIXGenerator::CreateWiXSourceFiles()
   cmWIXFilesSourceWriter fileDefinitions(this->Logger,
                                          fileDefinitionsFilename);
 
+  // if install folder is supposed to be set absolutely, the default
+  // component guid "*" cannot be used
+  fileDefinitions.GenerateComponentGuids =
+    cmSystemTools::IsOn(GetOption("CPACK_WIX_SKIP_PROGRAM_FOLDER"));
+
   fileDefinitions.BeginElement("Fragment");
 
   std::string featureDefinitionsFilename =
@@ -566,6 +572,9 @@ bool cmCPackWIXGenerator::CreateWiXSourceFiles()
 
 std::string cmCPackWIXGenerator::GetProgramFilesFolderId() const
 {
+  if (cmSystemTools::IsOn(GetOption("CPACK_WIX_SKIP_PROGRAM_FOLDER"))) {
+    return "";
+  }
   if (GetArchitecture() == "x86") {
     return "ProgramFilesFolder";
   } else {

Source/CPack/WiX/cmWIXDirectoriesSourceWriter.cxx

@@ -52,8 +52,12 @@ size_t cmWIXDirectoriesSourceWriter::BeginInstallationPrefixDirectory(
   std::string const& programFilesFolderId,
   std::string const& installRootString)
 {
-  BeginElement("Directory");
-  AddAttribute("Id", programFilesFolderId);
+  size_t offset = 1;
+  if (!programFilesFolderId.empty()) {
+    BeginElement("Directory");
+    AddAttribute("Id", programFilesFolderId);
+    offset = 0;
+  }
 
   std::vector<std::string> installRoot;
 
@@ -77,7 +81,7 @@ size_t cmWIXDirectoriesSourceWriter::BeginInstallationPrefixDirectory(
     AddAttribute("Name", installRoot[i]);
   }
 
-  return installRoot.size();
+  return installRoot.size() - offset;
 }
 
 void cmWIXDirectoriesSourceWriter::EndInstallationPrefixDirectory(size_t size)

Source/CPack/WiX/cmWIXFilesSourceWriter.cxx

@@ -16,6 +16,9 @@
 
 #include <cmInstalledFile.h>
 
+#include <cmSystemTools.h>
+#include <cmUuid.h>
+
 #include <sys/types.h>
 // include sys/stat.h after sys/types.h
 #include <sys/stat.h>
@@ -23,6 +26,7 @@
 cmWIXFilesSourceWriter::cmWIXFilesSourceWriter(cmCPackLog* logger,
                                                std::string const& filename)
   : cmWIXSourceWriter(logger, filename)
+  , GenerateComponentGuids(false)
 {
 }
 
@@ -126,12 +130,20 @@ std::string cmWIXFilesSourceWriter::EmitComponentFile(
   std::string componentId = std::string("CM_C") + id;
   std::string fileId = std::string("CM_F") + id;
 
+  std::string guid = "*";
+  if (this->GenerateComponentGuids) {
+    std::string md5 = cmSystemTools::ComputeStringMD5(componentId);
+    cmUuid uuid;
+    std::vector<unsigned char> ns;
+    guid = uuid.FromMd5(ns, md5);
+  }
+
   BeginElement("DirectoryRef");
   AddAttribute("Id", directoryId);
 
   BeginElement("Component");
   AddAttribute("Id", componentId);
-  AddAttribute("Guid", "*");
+  AddAttribute("Guid", guid);
 
   if (installedFile) {
     if (installedFile->GetPropertyAsBool("CPACK_NEVER_OVERWRITE")) {

Source/CPack/WiX/cmWIXFilesSourceWriter.h

@@ -47,6 +47,8 @@ public:
                                 std::string const& id,
                                 std::string const& filePath, cmWIXPatch& patch,
                                 cmInstalledFile const* installedFile);
+
+  bool GenerateComponentGuids;
 };
 
 #endif