cmStateSnapshot::GetDefinition(): Return std::string const*

Expose std::string type used internally in cmDefinitions instead of const char*

Source/cmDefinitions.cxx

@@ -30,11 +30,11 @@ cmDefinitions::Def const& cmDefinitions::GetInternal(const std::string& key,
   return begin->Map.insert(MapType::value_type(key, def)).first->second;
 }
 
-const char* cmDefinitions::Get(const std::string& key, StackIter begin,
-                               StackIter end)
+const std::string* cmDefinitions::Get(const std::string& key, StackIter begin,
+                                      StackIter end)
 {
   Def const& def = cmDefinitions::GetInternal(key, begin, end, false);
-  return def.Exists ? def.c_str() : nullptr;
+  return def.Exists ? &def : nullptr;
 }
 
 void cmDefinitions::Raise(const std::string& key, StackIter begin,

Source/cmDefinitions.h

@@ -23,8 +23,8 @@ class cmDefinitions
   typedef cmLinkedTree<cmDefinitions>::iterator StackIter;
 
 public:
-  static const char* Get(const std::string& key, StackIter begin,
-                         StackIter end);
+  static const std::string* Get(const std::string& key, StackIter begin,
+                                StackIter end);
 
   static void Raise(const std::string& key, StackIter begin, StackIter end);
 

Source/cmMakefile.cxx

@@ -2368,8 +2368,10 @@ const char* cmMakefile::GetRequiredDefinition(const std::string& name) const
 
 bool cmMakefile::IsDefinitionSet(const std::string& name) const
 {
-  const char* def = this->StateSnapshot.GetDefinition(name);
-  if (!def) {
+  const char* def;
+  if (const std::string* d = this->StateSnapshot.GetDefinition(name)) {
+    def = d->c_str();
+  } else {
     def = this->GetState()->GetInitializedCacheValue(name);
   }
 #ifdef CMAKE_BUILD_WITH_CMAKE
@@ -2385,8 +2387,10 @@ bool cmMakefile::IsDefinitionSet(const std::string& name) const
 
 const char* cmMakefile::GetDefinition(const std::string& name) const
 {
-  const char* def = this->StateSnapshot.GetDefinition(name);
-  if (!def) {
+  const char* def;
+  if (const std::string* d = this->StateSnapshot.GetDefinition(name)) {
+    def = d->c_str();
+  } else {
     def = this->GetState()->GetInitializedCacheValue(name);
   }
 #ifdef CMAKE_BUILD_WITH_CMAKE
@@ -2402,8 +2406,9 @@ const char* cmMakefile::GetDefinition(const std::string& name) const
       // A callback was executed and may have caused re-allocation of the
       // variable storage.  Look it up again for now.
       // FIXME: Refactor variable storage to avoid this problem.
-      def = this->StateSnapshot.GetDefinition(name);
-      if (!def) {
+      if (const std::string* d = this->StateSnapshot.GetDefinition(name)) {
+        def = d->c_str();
+      } else {
         def = this->GetState()->GetInitializedCacheValue(name);
       }
     }

Source/cmOptionCommand.cxx

@@ -31,7 +31,7 @@ bool cmOptionCommand::InitialPass(std::vector<std::string> const& args,
   bool checkAndWarn = false;
   {
     auto status = this->Makefile->GetPolicyStatus(cmPolicies::CMP0077);
-    const char* existsBeforeSet =
+    const auto* existsBeforeSet =
       this->Makefile->GetStateSnapshot().GetDefinition(args[0]);
     switch (status) {
       case cmPolicies::WARN:
@@ -72,7 +72,7 @@ bool cmOptionCommand::InitialPass(std::vector<std::string> const& args,
                                      args[1].c_str(), cmStateEnums::BOOL);
 
   if (checkAndWarn) {
-    const char* existsAfterSet =
+    const auto* existsAfterSet =
       this->Makefile->GetStateSnapshot().GetDefinition(args[0]);
     if (!existsAfterSet) {
       std::ostringstream w;

Source/cmState.cxx

@@ -298,9 +298,9 @@ cmStateSnapshot cmState::Reset()
 
   {
     std::string srcDir =
-      cmDefinitions::Get("CMAKE_SOURCE_DIR", pos->Vars, pos->Root);
+      *cmDefinitions::Get("CMAKE_SOURCE_DIR", pos->Vars, pos->Root);
     std::string binDir =
-      cmDefinitions::Get("CMAKE_BINARY_DIR", pos->Vars, pos->Root);
+      *cmDefinitions::Get("CMAKE_BINARY_DIR", pos->Vars, pos->Root);
     this->VarTree.Clear();
     pos->Vars = this->VarTree.Push(this->VarTree.Root());
     pos->Parent = this->VarTree.Root();

Source/cmStateSnapshot.cxx

@@ -204,7 +204,8 @@ bool cmStateSnapshot::HasDefinedPolicyCMP0011()
   return !this->Position->Policies->IsEmpty();
 }
 
-const char* cmStateSnapshot::GetDefinition(std::string const& name) const
+std::string const* cmStateSnapshot::GetDefinition(
+  std::string const& name) const
 {
   assert(this->Position->Vars.IsValid());
   return cmDefinitions::Get(name, this->Position->Vars, this->Position->Root);
@@ -426,8 +427,8 @@ std::string cmStateSnapshot::GetProjectName() const
 
 void cmStateSnapshot::InitializeFromParent_ForSubdirsCommand()
 {
-  std::string currentSrcDir = this->GetDefinition("CMAKE_CURRENT_SOURCE_DIR");
-  std::string currentBinDir = this->GetDefinition("CMAKE_CURRENT_BINARY_DIR");
+  std::string currentSrcDir = *this->GetDefinition("CMAKE_CURRENT_SOURCE_DIR");
+  std::string currentBinDir = *this->GetDefinition("CMAKE_CURRENT_BINARY_DIR");
   this->InitializeFromParent();
   this->SetDefinition("CMAKE_SOURCE_DIR", this->State->GetSourceDirectory());
   this->SetDefinition("CMAKE_BINARY_DIR", this->State->GetBinaryDirectory());

Source/cmStateSnapshot.h

@@ -22,7 +22,7 @@ public:
   cmStateSnapshot(cmState* state = nullptr);
   cmStateSnapshot(cmState* state, cmStateDetail::PositionType position);
 
-  const char* GetDefinition(std::string const& name) const;
+  std::string const* GetDefinition(std::string const& name) const;
   bool IsInitialized(std::string const& name) const;
   void SetDefinition(std::string const& name, std::string const& value);
   void RemoveDefinition(std::string const& name);