13 files changed, 392 insertions, 46 deletions

diff --git a/Source/CPack/cmCPackComponentGroup.h b/Source/CPack/cmCPackComponentGroup.h
index 2e1703c..d080a87 100644
--- a/Source/CPack/cmCPackComponentGroup.h
+++ b/Source/CPack/cmCPackComponentGroup.h
@@ -70,12 +70,20 @@ public:
   /// Whether this component defaults to "disabled".
   bool IsDisabledByDefault : 1;
 
+  /// Whether this component should be downloaded on-the-fly. If false,
+  /// the component will be a part of the installation package.
+  bool IsDownloaded : 1;
+
   /// A description of this component.
   std::string Description;
 
   /// The installation types that this component is a part of.
   std::vector<cmCPackInstallationType *> InstallationTypes;
 
+  /// If IsDownloaded is true, the name of the archive file that
+  /// contains the files that are part of this component.
+  std::string ArchiveFile;
+
   /// The components that this component depends on.
   std::vector<cmCPackComponent *> Dependencies;
 
@@ -95,6 +103,8 @@ public:
 class cmCPackComponentGroup
 {
 public:
+ cmCPackComponentGroup() : ParentGroup(0) { }
+
   /// The name of the group (used to reference the group).
   std::string Name;
 
@@ -112,6 +122,12 @@ public:
 
   /// The components within this group.
   std::vector<cmCPackComponent*> Components;
+
+  /// The parent group of this component group (if any).
+  cmCPackComponentGroup *ParentGroup;
+
+  /// The subgroups of this group.
+  std::vector<cmCPackComponentGroup*> Subgroups;
 };
 
 #endif
diff --git a/Source/CPack/cmCPackGenerator.cxx b/Source/CPack/cmCPackGenerator.cxx
index f786f80..5090606 100644
--- a/Source/CPack/cmCPackGenerator.cxx
+++ b/Source/CPack/cmCPackGenerator.cxx
@@ -653,6 +653,14 @@ int cmCPackGenerator::InstallProjectViaInstallCMakeProjects(
             }
           mf->AddDefinition("CMAKE_INSTALL_PREFIX", dir.c_str());
 
+          if ( !cmsys::SystemTools::MakeDirectory(dir.c_str()))
+            {
+            cmCPackLogger(cmCPackLog::LOG_ERROR,
+                          "Problem creating temporary directory: " 
+                          << dir << std::endl);
+            return 0;
+            }
+
           cmCPackLogger(cmCPackLog::LOG_DEBUG,
                         "- Using DESTDIR + CPACK_INSTALL_PREFIX... (mf->AddDefinition)"
                         << std::endl);
@@ -664,6 +672,14 @@ int cmCPackGenerator::InstallProjectViaInstallCMakeProjects(
           {
           mf->AddDefinition("CMAKE_INSTALL_PREFIX", tempInstallDirectory.c_str());
 
+          if ( !cmsys::SystemTools::MakeDirectory(tempInstallDirectory.c_str()))
+            {
+            cmCPackLogger(cmCPackLog::LOG_ERROR,
+                          "Problem creating temporary directory: " 
+                          << tempInstallDirectory << std::endl);
+            return 0;
+            }
+
           cmCPackLogger(cmCPackLog::LOG_DEBUG,
                         "- Using non-DESTDIR install... (mf->AddDefinition)" << std::endl);
           cmCPackLogger(cmCPackLog::LOG_DEBUG,
@@ -1255,6 +1271,16 @@ cmCPackGenerator::GetComponent(const char *projectName, const char *name)
       = this->IsSet((macroPrefix + "_REQUIRED").c_str());
     component->IsDisabledByDefault
       = this->IsSet((macroPrefix + "_DISABLED").c_str());
+    component->IsDownloaded
+      = this->IsSet((macroPrefix + "_DOWNLOADED").c_str())
+        || cmSystemTools::IsOn(this->GetOption("CPACK_DOWNLOAD_ALL"));
+
+    const char* archiveFile = this->GetOption((macroPrefix + "_ARCHIVE_FILE").c_str());
+    if (archiveFile && *archiveFile)
+      {
+      component->ArchiveFile = archiveFile;
+      }
+
     const char* groupName = this->GetOption((macroPrefix + "_GROUP").c_str());
     if (groupName && *groupName) 
       {
@@ -1344,6 +1370,17 @@ cmCPackGenerator::GetComponentGroup(const char *projectName, const char *name)
       = this->IsSet((macroPrefix + "_BOLD_TITLE").c_str());
     group->IsExpandedByDefault
       = this->IsSet((macroPrefix + "_EXPANDED").c_str());
+    const char* parentGroupName 
+      = this->GetOption((macroPrefix + "_PARENT_GROUP").c_str());
+    if (parentGroupName && *parentGroupName)
+      {
+      group->ParentGroup = GetComponentGroup(projectName, parentGroupName);
+      group->ParentGroup->Subgroups.push_back(group);
+      }
+    else
+      {
+      group->ParentGroup = 0;
+      }
     }
   return group;
 }
diff --git a/Source/CPack/cmCPackNSISGenerator.cxx b/Source/CPack/cmCPackNSISGenerator.cxx
index cd4ffb8..7be5cb2 100644
--- a/Source/CPack/cmCPackNSISGenerator.cxx
+++ b/Source/CPack/cmCPackNSISGenerator.cxx
@@ -173,6 +173,9 @@ int cmCPackNSISGenerator::CompressFiles(const char* outFileName,
     std::string componentDescriptions;
     std::string groupDescriptions;
     std::string installTypesCode;
+    std::string defines;
+    cmOStringStream macrosOut;
+    bool anyDownloadedComponents = false;
 
     // Create installation types. The order is significant, so we first fill
     // in a vector based on the indices, and print them in that order.
@@ -201,7 +204,11 @@ int cmCPackNSISGenerator::CompressFiles(const char* outFileName,
          groupIt != this->ComponentGroups.end();
          ++groupIt)
       {
-      componentCode += this->CreateComponentGroupDescription(&groupIt->second);
+      if (groupIt->second.ParentGroup == 0)
+        {
+        componentCode += 
+          this->CreateComponentGroupDescription(&groupIt->second, macrosOut);
+        }
 
       // Add the group description, if any.
       if (!groupIt->second.Description.empty())
@@ -218,9 +225,19 @@ int cmCPackNSISGenerator::CompressFiles(const char* outFileName,
          compIt != this->Components.end();
          ++compIt)
       {
+      if (compIt->second.Files.empty())
+        {
+        // NSIS cannot cope with components that have no files.
+        continue;
+        }
+
+      anyDownloadedComponents =
+        anyDownloadedComponents || compIt->second.IsDownloaded;
+
       if (!compIt->second.Group)
         {
-        componentCode += this->CreateComponentDescription(&compIt->second);
+        componentCode 
+          += this->CreateComponentDescription(&compIt->second, macrosOut);
         }
 
       // Add this component to the various section lists.
@@ -228,6 +245,7 @@ int cmCPackNSISGenerator::CompressFiles(const char* outFileName,
       sectionList += compIt->first;
       sectionList += "\"\n";
       selectedVarsList += "Var " + compIt->first + "_selected\n";
+      selectedVarsList += "Var " + compIt->first + "_was_installed\n";
 
       // Add the component description, if any.
       if (!compIt->second.Description.empty())
@@ -238,6 +256,8 @@ int cmCPackNSISGenerator::CompressFiles(const char* outFileName,
         }
       }
 
+    componentCode += macrosOut.str();
+
     if (componentDescriptions.empty() && groupDescriptions.empty())
       {
       // Turn off the "Description" box
@@ -254,12 +274,23 @@ int cmCPackNSISGenerator::CompressFiles(const char* outFileName,
       this->SetOptionIfNotSet("CPACK_NSIS_INSTALLER_MUI_COMPONENTS_DESC", 
                               componentDescriptions.c_str());
       }
+
+    if (anyDownloadedComponents)
+      {
+      defines += "!define CPACK_USES_DOWNLOAD\n";
+      if (cmSystemTools::IsOn(this->GetOption("CPACK_ADD_REMOVE")))
+        {
+        defines += "!define CPACK_NSIS_ADD_REMOVE\n";
+        }
+      }
+
     this->SetOptionIfNotSet("CPACK_NSIS_INSTALLATION_TYPES", installTypesCode.c_str());
     this->SetOptionIfNotSet("CPACK_NSIS_PAGE_COMPONENTS", "!insertmacro MUI_PAGE_COMPONENTS");
     this->SetOptionIfNotSet("CPACK_NSIS_FULL_INSTALL", "");
     this->SetOptionIfNotSet("CPACK_NSIS_COMPONENT_SECTIONS", componentCode.c_str());
     this->SetOptionIfNotSet("CPACK_NSIS_COMPONENT_SECTION_LIST", sectionList.c_str());
     this->SetOptionIfNotSet("CPACK_NSIS_SECTION_SELECTED_VARS", selectedVarsList.c_str());
+    this->SetOption("CPACK_NSIS_DEFINES", defines.c_str());
     }
 
   this->ConfigureFile(nsisInInstallOptions.c_str(), 
@@ -559,7 +590,7 @@ bool cmCPackNSISGenerator::SupportsComponentInstallation() const
 //----------------------------------------------------------------------
 std::string 
 cmCPackNSISGenerator::
-CreateComponentDescription(cmCPackComponent *component) const
+CreateComponentDescription(cmCPackComponent *component, cmOStringStream& macrosOut)
 {
   // Basic description of the component
   std::string componentCode = "Section ";
@@ -590,46 +621,204 @@ CreateComponentDescription(cmCPackComponent *component) const
     componentCode += "  SectionIn" + out.str() + "\n";
     }
   componentCode += "  SetOutPath \"$INSTDIR\"\n";
-  componentCode += "  File /r \"${INST_DIR}\\" + component->Name + "\\*.*\"\n";
+
+  componentCode += "  IntCmp $" + component->Name 
+    + "_was_installed ${SF_SELECTED} noinstall_" + component->Name + "\n";
+
+  // Create the actual installation commands
+  if (component->IsDownloaded)
+    {
+    if (component->ArchiveFile.empty())
+      {
+      // Compute the name of the archive.
+      std::string packagesDir = this->GetOption("CPACK_TEMPORARY_DIRECTORY");
+      packagesDir += ".dummy";
+      cmOStringStream out;
+      out << cmSystemTools::GetFilenameWithoutLastExtension(packagesDir)
+        << "-" << component->Name << ".zip";
+      component->ArchiveFile = out.str();
+      }
+
+    // Create the directory for the upload area
+    const char* userUploadDirectory = this->GetOption("CPACK_UPLOAD_DIRECTORY");
+    std::string uploadDirectory;
+    if (userUploadDirectory && *userUploadDirectory)
+      {
+      uploadDirectory = userUploadDirectory;
+      }
+    else
+      {
+      uploadDirectory= this->GetOption("CPACK_PACKAGE_DIRECTORY");
+      uploadDirectory += "/CPackUploads";
+      }
+    if(!cmSystemTools::FileExists(uploadDirectory.c_str()))
+      {
+      if (!cmSystemTools::MakeDirectory(uploadDirectory.c_str()))
+        {
+        cmCPackLogger(cmCPackLog::LOG_ERROR,
+          "Unable to create NSIS upload directory " << uploadDirectory
+          << std::endl);
+        return "";
+        }
+      }
+
+    // Remove the old archive, if one exists
+    std::string archiveFile = uploadDirectory + '/' + component->ArchiveFile;
+    cmCPackLogger(cmCPackLog::LOG_OUTPUT,
+                  "-   Building downloaded component archive: " 
+                  << archiveFile << std::endl);
+    if (cmSystemTools::FileExists(archiveFile.c_str(), true))
+      {
+        if (!cmSystemTools::RemoveFile(archiveFile.c_str()))
+        {
+        cmCPackLogger(cmCPackLog::LOG_ERROR,
+          "Unable to remove archive file " << archiveFile
+          << std::endl);
+        return "";
+        }
+      }
+
+    // Find a ZIP program
+    if (!this->IsSet("ZIP_EXECUTABLE"))
+      {
+      this->ReadListFile("CPackZIP.cmake");
+
+      if (!this->IsSet("ZIP_EXECUTABLE"))
+        {
+        cmCPackLogger(cmCPackLog::LOG_ERROR,
+          "Unable to find ZIP program"
+          << std::endl);
+        return "";
+        }
+      }
+
+    // The directory where this component's files reside
+    std::string dirName = this->GetOption("CPACK_TEMPORARY_DIRECTORY");
+    dirName += '/';
+    dirName += component->Name;
+    dirName += '/';
+
+    // Build the list of files to go into this archive, and determine the 
+    // size of the installed component.
+    std::string zipListFileName = this->GetOption("CPACK_TEMPORARY_DIRECTORY");
+    zipListFileName += "/winZip.filelist";
+    bool needQuotesInFile 
+      = cmSystemTools::IsOn(this->GetOption("CPACK_ZIP_NEED_QUOTES"));
+    unsigned long totalSize = 0;
+    { // the scope is needed for cmGeneratedFileStream
+      cmGeneratedFileStream out(zipListFileName.c_str());
+      std::vector<std::string>::iterator fileIt;
+      for (fileIt = component->Files.begin(); 
+           fileIt != component->Files.end(); 
+           ++fileIt)
+        {
+        if ( needQuotesInFile )
+          {
+          out << "\"";
+          }
+        out << *fileIt;
+        if ( needQuotesInFile )
+          {
+          out << "\"";
+          }
+        out << std::endl;
+
+        totalSize += cmSystemTools::FileLength((dirName + *fileIt).c_str());
+        }
+    }
+
+    // Build the archive in the upload area
+    std::string cmd = this->GetOption("CPACK_ZIP_COMMAND");
+    cmsys::SystemTools::ReplaceString(cmd, "<ARCHIVE>", archiveFile.c_str());
+    cmsys::SystemTools::ReplaceString(cmd, "<FILELIST>", 
+                                      zipListFileName.c_str());
+    std::string output;
+    int retVal = -1;
+    int res = cmSystemTools::RunSingleCommand(cmd.c_str(), &output, &retVal, 
+                                              dirName.c_str(), false, 0);
+    if ( !res || retVal )
+    {
+      std::string tmpFile = this->GetOption("CPACK_TOPLEVEL_DIRECTORY");
+      tmpFile += "/CompressZip.log";
+      cmGeneratedFileStream ofs(tmpFile.c_str());
+      ofs << "# Run command: " << cmd.c_str() << std::endl
+        << "# Output:" << std::endl
+        << output.c_str() << std::endl;
+      cmCPackLogger(cmCPackLog::LOG_ERROR, "Problem running zip command: "
+        << cmd.c_str() << std::endl
+        << "Please check " << tmpFile.c_str() << " for errors" << std::endl);
+      return "";
+    }
+    
+    // Create the NSIS code to download this file on-the-fly.
+    unsigned totalSizeInKbytes = (totalSize + 512) / 1024;
+    if (totalSizeInKbytes == 0)
+      {
+      totalSizeInKbytes = 1;
+      }
+    cmOStringStream out;
+    out << "  AddSize " << totalSizeInKbytes << "\n"
+        << "  Push \"" << component->ArchiveFile << "\"\n"
+        << "  Call DownloadFile\n"
+        << "  ZipDLL::extractall \"$INSTDIR\\" 
+        << component->ArchiveFile << "\" \"$INSTDIR\"\n"
+        <<  "  Pop $2 ; error message\n"
+                     "  StrCmp $2 \"success\" +2 0\n"
+                     "  MessageBox MB_OK \"Failed to unzip $2\"\n"
+                     "  Delete $INSTDIR\\$0\n";
+    componentCode += out.str();
+    }
+  else
+    {
+    componentCode += "  File /r \"${INST_DIR}\\" + component->Name + "\\*.*\"\n";
+    }
+  componentCode += "  noinstall_" + component->Name + ":\n";
   componentCode += "SectionEnd\n";
 
   // Macro used to remove the component
-  componentCode += "!macro Remove_${" + component->Name + "}\n";
+  macrosOut << "!macro Remove_${" << component->Name << "}\n";
+  macrosOut << "  IntCmp $" << component->Name << "_was_installed 0 noremove_"
+            << component->Name << "\n";
   std::vector<std::string>::iterator pathIt;
   for (pathIt = component->Files.begin(); 
        pathIt != component->Files.end(); 
        ++pathIt) 
     {
-    componentCode += "  Delete \"$INSTDIR\\" + *pathIt + "\"\n";
+    macrosOut << "  Delete \"$INSTDIR\\" 
+              << cmSystemTools::ConvertToWindowsOutputPath(pathIt->c_str())
+              << "\"\n";
     }
   for (pathIt = component->Directories.begin(); 
        pathIt != component->Directories.end(); 
        ++pathIt) 
     {
-    componentCode += "  RMDir \"$INSTDIR\\" + *pathIt + "\"\n";
+    macrosOut << "  RMDir \"$INSTDIR\\" 
+              << cmSystemTools::ConvertToWindowsOutputPath(pathIt->c_str())
+              << "\"\n";
     }
-  componentCode += "!macroend\n";
+  macrosOut << "  noremove_" << component->Name << ":\n";
+  macrosOut << "!macroend\n";
 
   // Macro used to select each of the components that this component
   // depends on.
   std::set<cmCPackComponent *> visited;
-  componentCode += "!macro Select_" + component->Name + "_depends\n";
-  componentCode += CreateSelectionDependenciesDescription(component, visited);
-  componentCode += "!macroend\n";
+  macrosOut << "!macro Select_" << component->Name << "_depends\n";
+  macrosOut << CreateSelectionDependenciesDescription(component, visited);
+  macrosOut << "!macroend\n";
 
   // Macro used to deselect each of the components that depend on this
   // component.
   visited.clear();
-  componentCode += "!macro Deselect_required_by_" + component->Name + "\n";
-  componentCode += CreateDeselectionDependenciesDescription(component, visited);
-  componentCode += "!macroend\n";
+  macrosOut << "!macro Deselect_required_by_" << component->Name << "\n";
+  macrosOut << CreateDeselectionDependenciesDescription(component, visited);
+  macrosOut << "!macroend\n";
   return componentCode;
 }
 
 //----------------------------------------------------------------------
 std::string cmCPackNSISGenerator::CreateSelectionDependenciesDescription
               (cmCPackComponent *component,
-               std::set<cmCPackComponent *>& visited) const
+               std::set<cmCPackComponent *>& visited)
 {
   // Don't visit a component twice
   if (visited.count(component)) 
@@ -660,7 +849,7 @@ std::string cmCPackNSISGenerator::CreateSelectionDependenciesDescription
 //----------------------------------------------------------------------
 std::string cmCPackNSISGenerator::CreateDeselectionDependenciesDescription
               (cmCPackComponent *component,
-                   std::set<cmCPackComponent *>& visited) const
+                   std::set<cmCPackComponent *>& visited)
 {
   // Don't visit a component twice
   if (visited.count(component)) 
@@ -692,9 +881,10 @@ std::string cmCPackNSISGenerator::CreateDeselectionDependenciesDescription
 //----------------------------------------------------------------------
 std::string 
 cmCPackNSISGenerator::
-CreateComponentGroupDescription(cmCPackComponentGroup *group) const
+CreateComponentGroupDescription(cmCPackComponentGroup *group, 
+                                cmOStringStream& macrosOut)
 {
-  if (group->Components.empty())
+  if (group->Components.empty() && group->Subgroups.empty())
     {
     // Silently skip empty groups. NSIS doesn't support them.
     return std::string();
@@ -713,12 +903,25 @@ CreateComponentGroupDescription(cmCPackComponentGroup *group) const
     {
     code += "\"" + group->DisplayName + "\" " + group->Name + "\n";
     }
+
+  std::vector<cmCPackComponentGroup*>::iterator groupIt;
+  for (groupIt = group->Subgroups.begin(); groupIt != group->Subgroups.end();
+       ++groupIt)
+    {
+    code += this->CreateComponentGroupDescription(*groupIt, macrosOut);
+    }
+
   std::vector<cmCPackComponent*>::iterator comp;
   for (comp = group->Components.begin(); 
        comp != group->Components.end(); 
        ++comp)
     {
-    code += this->CreateComponentDescription(*comp);
+    if ((*comp)->Files.empty())
+      {
+      continue;
+      }
+
+    code += this->CreateComponentDescription(*comp, macrosOut);
     }
   code += "SectionGroupEnd\n";
   return code;
diff --git a/Source/CPack/cmCPackNSISGenerator.h b/Source/CPack/cmCPackNSISGenerator.h
index 70068e41..5299a91 100644
--- a/Source/CPack/cmCPackNSISGenerator.h
+++ b/Source/CPack/cmCPackNSISGenerator.h
@@ -53,24 +53,30 @@ protected:
   virtual bool SupportsComponentInstallation() const;
 
   /// Produce a string that contains the NSIS code to describe a 
-  /// particular component.
-  std::string CreateComponentDescription(cmCPackComponent *component) const;
+  /// particular component. Any added macros will be emitted via 
+  /// macrosOut.
+  std::string 
+  CreateComponentDescription(cmCPackComponent *component,
+                             cmOStringStream& macrosOut);
 
   /// Produce NSIS code that selects all of the components that this component
   /// depends on, recursively.
   std::string CreateSelectionDependenciesDescription
                 (cmCPackComponent *component,
-                 std::set<cmCPackComponent *>& visited) const;
+                 std::set<cmCPackComponent *>& visited);
 
   /// Produce NSIS code that de-selects all of the components that are dependent
   /// on this component, recursively.
   std::string CreateDeselectionDependenciesDescription
                 (cmCPackComponent *component,
-                 std::set<cmCPackComponent *>& visited) const;
+                 std::set<cmCPackComponent *>& visited);
 
   /// Produce a string that contains the NSIS code to describe a 
-  /// particular component group, including its components.
-  std::string CreateComponentGroupDescription(cmCPackComponentGroup *group) const;
+  /// particular component group, including its components. Any
+  /// added macros will be emitted via macrosOut.
+  std::string 
+  CreateComponentGroupDescription(cmCPackComponentGroup *group,
+                                  cmOStringStream& macrosOut);
 
   /// Translations any newlines found in the string into \r\n, so that the 
   /// resulting string can be used within NSIS.
diff --git a/Source/CPack/cmCPackPackageMakerGenerator.cxx b/Source/CPack/cmCPackPackageMakerGenerator.cxx
index 04b7899..a156971 100644
--- a/Source/CPack/cmCPackPackageMakerGenerator.cxx
+++ b/Source/CPack/cmCPackPackageMakerGenerator.cxx
@@ -580,7 +580,10 @@ WriteDistributionFile(const char* metapackageFile)
        groupIt != this->ComponentGroups.end(); 
        ++groupIt)
     {
-    CreateChoiceOutline(groupIt->second, choiceOut);
+    if (groupIt->second.ParentGroup == 0)
+      {
+      CreateChoiceOutline(groupIt->second, choiceOut);
+      }
     }
 
   // Emit the outline for the non-grouped components
@@ -622,6 +625,13 @@ cmCPackPackageMakerGenerator::
 CreateChoiceOutline(const cmCPackComponentGroup& group, cmOStringStream& out)
 {
   out << "<line choice=\"" << group.Name << "Choice\">" << std::endl;
+  std::vector<cmCPackComponentGroup*>::const_iterator groupIt;
+  for (groupIt = group.Subgroups.begin(); groupIt != group.Subgroups.end();
+       ++groupIt)
+    {
+    CreateChoiceOutline(**groupIt, out);
+    }
+
   std::vector<cmCPackComponent*>::const_iterator compIt;
   for (compIt = group.Components.begin(); compIt != group.Components.end();
        ++compIt)
diff --git a/Source/cmGetCMakePropertyCommand.cxx b/Source/cmGetCMakePropertyCommand.cxx
index 09e7068..02e21bd 100644
--- a/Source/cmGetCMakePropertyCommand.cxx
+++ b/Source/cmGetCMakePropertyCommand.cxx
@@ -49,6 +49,22 @@ bool cmGetCMakePropertyCommand
     {
     this->Makefile->GetListOfMacros(output);
     }
+  else if ( args[1] == "COMPONENTS" )
+    {
+    const std::set<cmStdString>* components
+      = this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+        ->GetInstallComponents();
+    std::set<cmStdString>::const_iterator compIt;
+    output = "";
+    for (compIt = components->begin(); compIt != components->end(); ++compIt)
+      {
+      if (compIt != components->begin())
+        {
+        output += ";";
+        }
+      output += *compIt;
+      }
+    }
   else
     {
     const char *prop = 
diff --git a/Source/cmGetCMakePropertyCommand.h b/Source/cmGetCMakePropertyCommand.h
index c1f66d9..b3cb442 100644
--- a/Source/cmGetCMakePropertyCommand.h
+++ b/Source/cmGetCMakePropertyCommand.h
@@ -62,7 +62,8 @@ public:
         "Get a property from the CMake instance.  The value of the "
         "property is stored in the variable VAR. If the property is "
         "not found, CMake will report an error. Some supported properties "
-        "include: VARIABLES, CACHE_VARIABLES, COMMANDS, and MACROS.";
+        "include: VARIABLES, CACHE_VARIABLES, COMMANDS, MACROS, and "
+        "COMPONENTS.";
     }
   
   cmTypeMacro(cmGetCMakePropertyCommand, cmCommand);
diff --git a/Source/cmGlobalGenerator.h b/Source/cmGlobalGenerator.h
index 2865a38..a76890b 100644
--- a/Source/cmGlobalGenerator.h
+++ b/Source/cmGlobalGenerator.h
@@ -139,6 +139,9 @@ public:
 
   void AddInstallComponent(const char* component);
 
+  const std::set<cmStdString>* GetInstallComponents() const 
+  { return &InstallComponents; }
+
   ///! Add one installed target to the sets of the exports
   void AddTargetToExports(const char* exportSet, cmTarget* target, 
                           cmInstallTargetGenerator* archive,
diff --git a/Source/cmInstallCommand.cxx b/Source/cmInstallCommand.cxx
index 6ce7ae5..eb162f5 100644
--- a/Source/cmInstallCommand.cxx
+++ b/Source/cmInstallCommand.cxx
@@ -384,6 +384,17 @@ bool cmInstallCommand::HandleTargetsMode(std::vector<std::string> const& args)
         }
     }
 
+  // Keep track of whether we will be performing an installation of
+  // any files of the given type.
+  bool installsArchive = false;
+  bool installsLibrary = false;
+  bool installsRuntime = false;
+  bool installsFramework = false;
+  bool installsBundle = false;
+  bool installsPrivateHeader = false;
+  bool installsPublicHeader = false;
+  bool installsResource = false;
+
   // Generate install script code to install the given targets.
   for(std::vector<cmTarget*>::iterator ti = targets.begin();
       ti != targets.end(); ++ti)
@@ -691,6 +702,16 @@ bool cmInstallCommand::HandleTargetsMode(std::vector<std::string> const& args)
       }
     }
 
+    // Keep track of whether we're installing anything in each category
+    installsArchive = installsArchive || archiveGenerator != 0;
+    installsLibrary = installsLibrary || libraryGenerator != 0;
+    installsRuntime = installsRuntime || runtimeGenerator != 0;
+    installsFramework = installsFramework || frameworkGenerator != 0;
+    installsBundle = installsBundle || bundleGenerator != 0;
+    installsPrivateHeader = installsPrivateHeader || privateHeaderGenerator != 0;
+    installsPublicHeader = installsPublicHeader || publicHeaderGenerator != 0;
+    installsResource = installsResource || resourceGenerator;
+
     this->Makefile->AddInstallGenerator(archiveGenerator);
     this->Makefile->AddInstallGenerator(libraryGenerator);
     this->Makefile->AddInstallGenerator(runtimeGenerator);
@@ -713,22 +734,46 @@ bool cmInstallCommand::HandleTargetsMode(std::vector<std::string> const& args)
     }
 
   // Tell the global generator about any installation component names specified
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-                     ->AddInstallComponent(archiveArgs.GetComponent().c_str());
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-                     ->AddInstallComponent(libraryArgs.GetComponent().c_str());
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-                     ->AddInstallComponent(runtimeArgs.GetComponent().c_str());
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-                   ->AddInstallComponent(frameworkArgs.GetComponent().c_str());
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-                      ->AddInstallComponent(bundleArgs.GetComponent().c_str());
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-               ->AddInstallComponent(privateHeaderArgs.GetComponent().c_str());
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-                ->AddInstallComponent(publicHeaderArgs.GetComponent().c_str());
-  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
-                    ->AddInstallComponent(resourceArgs.GetComponent().c_str());
+  if (installsArchive)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                       ->AddInstallComponent(archiveArgs.GetComponent().c_str());
+    }
+  if (installsLibrary)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                       ->AddInstallComponent(libraryArgs.GetComponent().c_str());
+    }
+  if (installsRuntime)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                       ->AddInstallComponent(runtimeArgs.GetComponent().c_str());
+    }
+  if (installsFramework)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                     ->AddInstallComponent(frameworkArgs.GetComponent().c_str());
+    }
+  if (installsBundle)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                        ->AddInstallComponent(bundleArgs.GetComponent().c_str());
+    }
+  if (installsPrivateHeader)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                 ->AddInstallComponent(privateHeaderArgs.GetComponent().c_str());
+    }
+  if (installsPublicHeader)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                  ->AddInstallComponent(publicHeaderArgs.GetComponent().c_str());
+    }
+  if (installsResource)
+    {
+    this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                      ->AddInstallComponent(resourceArgs.GetComponent().c_str());
+    }
 
   return true;
 }
diff --git a/Source/cmInstallFilesCommand.cxx b/Source/cmInstallFilesCommand.cxx
index 36e7e25..a352244 100644
--- a/Source/cmInstallFilesCommand.cxx
+++ b/Source/cmInstallFilesCommand.cxx
@@ -59,6 +59,9 @@ bool cmInstallFilesCommand
       }
     }
   
+  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                       ->AddInstallComponent("Unspecified");
+
   return true;
 }
 
@@ -126,7 +129,7 @@ void cmInstallFilesCommand::CreateInstallGenerator() const
   // Use a file install generator.
   const char* no_permissions = "";
   const char* no_rename = "";
-  const char* no_component = "";
+  const char* no_component = "Unspecified";
   std::vector<std::string> no_configurations;
   this->Makefile->AddInstallGenerator(
     new cmInstallFilesGenerator(this->Files,
diff --git a/Source/cmInstallProgramsCommand.cxx b/Source/cmInstallProgramsCommand.cxx
index 6a55f17..d7557d0 100644
--- a/Source/cmInstallProgramsCommand.cxx
+++ b/Source/cmInstallProgramsCommand.cxx
@@ -38,6 +38,9 @@ bool cmInstallProgramsCommand
     this->FinalArgs.push_back(*s);
     }  
   
+  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                       ->AddInstallComponent("Unspecified");
+
   return true;
 }
 
@@ -87,7 +90,7 @@ void cmInstallProgramsCommand::FinalPass()
   // Use a file install generator.
   const char* no_permissions = "";
   const char* no_rename = "";
-  const char* no_component = "";
+  const char* no_component = "Unspecified";
   std::vector<std::string> no_configurations;
   this->Makefile->AddInstallGenerator(
     new cmInstallFilesGenerator(this->Files,
diff --git a/Source/cmInstallTargetGenerator.h b/Source/cmInstallTargetGenerator.h
index 61357b3..cd4d6e5 100644
--- a/Source/cmInstallTargetGenerator.h
+++ b/Source/cmInstallTargetGenerator.h
@@ -31,7 +31,7 @@ public:
     const char* file_permissions = "",
     std::vector<std::string> const& configurations 
     = std::vector<std::string>(),
-    const char* component = "",
+    const char* component = "Unspecified",
     bool optional = false
     );
   virtual ~cmInstallTargetGenerator();
diff --git a/Source/cmInstallTargetsCommand.cxx b/Source/cmInstallTargetsCommand.cxx
index d3ecddf..cfcdc0c 100644
--- a/Source/cmInstallTargetsCommand.cxx
+++ b/Source/cmInstallTargetsCommand.cxx
@@ -62,6 +62,9 @@ bool cmInstallTargetsCommand
       }
     }
 
+  this->Makefile->GetLocalGenerator()->GetGlobalGenerator()
+                       ->AddInstallComponent("Unspecified");
+
   return true;
 }