use string_views to avoid memory allocations

3 files changed, 18 insertions, 15 deletions

diff --git a/Source/CPack/WiX/cmWIXAccessControlList.cxx b/Source/CPack/WiX/cmWIXAccessControlList.cxx
index 3668b46..9685a7f 100644
--- a/Source/CPack/WiX/cmWIXAccessControlList.cxx
+++ b/Source/CPack/WiX/cmWIXAccessControlList.cxx
@@ -2,6 +2,8 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmWIXAccessControlList.h"
 
+#include <cm/string_view>
+
 #include "cmCPackGenerator.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -35,12 +37,13 @@ void cmWIXAccessControlList::CreatePermissionElement(std::string const& entry)
     return;
   }
 
-  std::string user_and_domain = entry.substr(0, pos);
-  std::string permission_string = entry.substr(pos + 1);
+  cm::string_view enview(entry);
+  cm::string_view user_and_domain = enview.substr(0, pos);
+  cm::string_view permission_string = enview.substr(pos + 1);
 
   pos = user_and_domain.find('@');
-  std::string user;
-  std::string domain;
+  cm::string_view user;
+  cm::string_view domain;
   if (pos != std::string::npos) {
     user = user_and_domain.substr(0, pos);
     domain = user_and_domain.substr(pos + 1);
@@ -51,9 +54,9 @@ void cmWIXAccessControlList::CreatePermissionElement(std::string const& entry)
   std::vector<std::string> permissions = cmTokenize(permission_string, ",");
 
   this->SourceWriter.BeginElement("Permission");
-  this->SourceWriter.AddAttribute("User", user);
+  this->SourceWriter.AddAttribute("User", std::string(user));
   if (!domain.empty()) {
-    this->SourceWriter.AddAttribute("Domain", domain);
+    this->SourceWriter.AddAttribute("Domain", std::string(domain));
   }
   for (std::string const& permission : permissions) {
     this->EmitBooleanAttribute(entry, cmTrimWhitespace(permission));
diff --git a/Source/CPack/cmCPackNSISGenerator.cxx b/Source/CPack/cmCPackNSISGenerator.cxx
index f7edc91..6b30407 100644
--- a/Source/CPack/cmCPackNSISGenerator.cxx
+++ b/Source/CPack/cmCPackNSISGenerator.cxx
@@ -68,7 +68,7 @@ int cmCPackNSISGenerator::PackageFiles()
 
       // Use the custom component install directory if we have one
       if (pos != std::string::npos) {
-        const std::string componentName = fileN.substr(0, pos);
+        auto componentName = cm::string_view(fileN).substr(0, pos);
         outputDir = CustomComponentInstallDirectory(componentName);
       } else {
         outputDir = CustomComponentInstallDirectory(fileN);
@@ -672,7 +672,7 @@ std::string cmCPackNSISGenerator::CreateComponentDescription(
 
   const std::string componentOutputDir =
     CustomComponentInstallDirectory(component->Name);
-  componentCode += "  SetOutPath \"" + componentOutputDir + "\"\n";
+  componentCode += cmStrCat("  SetOutPath \"", componentOutputDir, "\"\n");
 
   // Create the actual installation commands
   if (component->IsDownloaded) {
@@ -921,12 +921,11 @@ std::string cmCPackNSISGenerator::CreateComponentGroupDescription(
 }
 
 std::string cmCPackNSISGenerator::CustomComponentInstallDirectory(
-  const std::string& componentName)
+  cm::string_view componentName)
 {
-  const char* outputDir =
-    this->GetOption("CPACK_NSIS_" + componentName + "_INSTALL_DIRECTORY");
-  const std::string componentOutputDir = (outputDir ? outputDir : "$INSTDIR");
-  return componentOutputDir;
+  const char* outputDir = this->GetOption(
+    cmStrCat("CPACK_NSIS_", componentName, "_INSTALL_DIRECTORY"));
+  return outputDir ? outputDir : "$INSTDIR";
 }
 
 std::string cmCPackNSISGenerator::TranslateNewlines(std::string str)
diff --git a/Source/CPack/cmCPackNSISGenerator.h b/Source/CPack/cmCPackNSISGenerator.h
index 0af37af..88cba45 100644
--- a/Source/CPack/cmCPackNSISGenerator.h
+++ b/Source/CPack/cmCPackNSISGenerator.h
@@ -10,6 +10,8 @@
 #include <string>
 #include <vector>
 
+#include <cm/string_view>
+
 #include "cmCPackGenerator.h"
 
 class cmCPackComponent;
@@ -75,8 +77,7 @@ protected:
 
   /// Returns the custom install directory if available for the specified
   /// component, otherwise $INSTDIR is returned.
-  std::string CustomComponentInstallDirectory(
-    const std::string& componentName);
+  std::string CustomComponentInstallDirectory(cm::string_view componentName);
 
   /// Translations any newlines found in the string into \\r\\n, so that the
   /// resulting string can be used within NSIS.