Introduce CM_UNORDERED_MAP

Avoid duplicating switch among std::unordered_map, cmsys::hash_map, and
std::map.

Source/cmDefinitions.h

@@ -6,20 +6,11 @@
 #include <cmConfigure.h>
 
 #include "cmLinkedTree.h"
+#include "cm_unordered_map.hxx"
 
 #include <string>
 #include <vector>
 
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-#include <unordered_map>
-#else
-#include "cmsys/hash_map.hxx"
-#endif
-#else
-#include <map>
-#endif
-
 /** \class cmDefinitions
  * \brief Store a scope of variable definitions for CMake language.
  *
@@ -85,15 +76,7 @@ private:
   };
   static Def NoDef;
 
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-  typedef std::unordered_map<std::string, Def> MapType;
-#else
-  typedef cmsys::hash_map<std::string, Def> MapType;
-#endif
-#else
-  typedef std::map<std::string, Def> MapType;
-#endif
+  typedef CM_UNORDERED_MAP<std::string, Def> MapType;
   MapType Map;
 
   static Def const& GetInternal(const std::string& key, StackIter begin,

Source/cmFileTimeComparison.cxx

@@ -7,14 +7,7 @@
 #include <time.h>
 #include <utility>
 
-// Use a hash table to avoid duplicate file time checks from disk.
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-#include <unordered_map>
-#else
-#include <cmsys/hash_map.hxx>
-#endif
-#endif
+#include "cm_unordered_map.hxx"
 
 // Use a platform-specific API to get file times efficiently.
 #if !defined(_WIN32) || defined(__CYGWIN__)
@@ -35,27 +28,9 @@ public:
   bool FileTimesDiffer(const char* f1, const char* f2);
 
 private:
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-  // Use a hash table to efficiently map from file name to modification time.
-  class HashString
-  {
-  public:
-    size_t operator()(const std::string& s) const { return h(s.c_str()); }
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-    std::hash<const char*> h;
-#else
-    cmsys::hash<const char*> h;
-#endif
-  };
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-  typedef std::unordered_map<std::string,
-#else
-  typedef cmsys::hash_map<std::string,
-#endif
-                             cmFileTimeComparison_Type, HashString>
+  typedef CM_UNORDERED_MAP<std::string, cmFileTimeComparison_Type>
     FileStatsMap;
   FileStatsMap Files;
-#endif
 
   // Internal methods to lookup and compare modification times.
   inline bool Stat(const char* fname, cmFileTimeComparison_Type* st);
@@ -68,7 +43,6 @@ private:
 bool cmFileTimeComparisonInternal::Stat(const char* fname,
                                         cmFileTimeComparison_Type* st)
 {
-#if defined(CMAKE_BUILD_WITH_CMAKE)
   // Use the stored time if available.
   cmFileTimeComparisonInternal::FileStatsMap::iterator fit =
     this->Files.find(fname);
@@ -76,7 +50,6 @@ bool cmFileTimeComparisonInternal::Stat(const char* fname,
     *st = fit->second;
     return true;
   }
-#endif
 
 #if !defined(_WIN32) || defined(__CYGWIN__)
   // POSIX version.  Use the stat function.
@@ -97,11 +70,8 @@ bool cmFileTimeComparisonInternal::Stat(const char* fname,
   *st = fdata.ftLastWriteTime;
 #endif
 
-#if defined(CMAKE_BUILD_WITH_CMAKE)
   // Store the time for future use.
   this->Files[fname] = *st;
-#endif
-
   return true;
 }
 

Source/cmGlobalGenerator.h

@@ -12,6 +12,7 @@
 #include "cmTarget.h"
 #include "cmTargetDepend.h"
 #include "cm_codecvt.hxx"
+#include "cm_unordered_map.hxx"
 
 #include <iosfwd>
 #include <map>
@@ -22,11 +23,6 @@
 
 #if defined(CMAKE_BUILD_WITH_CMAKE)
 #include "cmFileLockPool.h"
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-#include <unordered_map>
-#else
-#include <cmsys/hash_map.hxx>
-#endif
 #endif
 
 class cmCustomCommandLines;
@@ -468,22 +464,9 @@ protected:
   const char* GetPredefinedTargetsFolder();
 
 private:
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-  typedef std::unordered_map<std::string, cmTarget*> TargetMap;
-  typedef std::unordered_map<std::string, cmGeneratorTarget*>
-    GeneratorTargetMap;
-  typedef std::unordered_map<std::string, cmMakefile*> MakefileMap;
-#else
-  typedef cmsys::hash_map<std::string, cmTarget*> TargetMap;
-  typedef cmsys::hash_map<std::string, cmGeneratorTarget*> GeneratorTargetMap;
-  typedef cmsys::hash_map<std::string, cmMakefile*> MakefileMap;
-#endif
-#else
-  typedef std::map<std::string, cmTarget*> TargetMap;
-  typedef std::map<std::string, cmGeneratorTarget*> GeneratorTargetMap;
-  typedef std::map<std::string, cmMakefile*> MakefileMap;
-#endif
+  typedef CM_UNORDERED_MAP<std::string, cmTarget*> TargetMap;
+  typedef CM_UNORDERED_MAP<std::string, cmGeneratorTarget*> GeneratorTargetMap;
+  typedef CM_UNORDERED_MAP<std::string, cmMakefile*> MakefileMap;
   // Map efficiently from target name to cmTarget instance.
   // Do not use this structure for looping over all targets.
   // It contains both normal and globally visible imported targets.

Source/cmMakefile.h

@@ -12,6 +12,7 @@
 #include "cmStateSnapshot.h"
 #include "cmTarget.h"
 #include "cmTargetLinkLibraryType.h"
+#include "cm_unordered_map.hxx"
 #include "cmake.h"
 
 #if defined(CMAKE_BUILD_WITH_CMAKE)
@@ -27,14 +28,6 @@
 #include <string>
 #include <vector>
 
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-#include <unordered_map>
-#else
-#include <cmsys/hash_map.hxx>
-#endif
-#endif
-
 class cmCommand;
 class cmCompiledGeneratorExpression;
 class cmCustomCommandLines;
@@ -783,15 +776,6 @@ protected:
 
   // libraries, classes, and executables
   mutable cmTargets Targets;
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-  typedef std::unordered_map<std::string, cmTarget*> TargetMap;
-#else
-  typedef cmsys::hash_map<std::string, cmTarget*> TargetMap;
-#endif
-#else
-  typedef std::map<std::string, cmTarget*> TargetMap;
-#endif
   std::map<std::string, std::string> AliasTargets;
   std::vector<cmSourceFile*> SourceFiles;
 
@@ -863,6 +847,7 @@ private:
   friend class cmParseFileScope;
 
   std::vector<cmTarget*> ImportedTargetsOwned;
+  typedef CM_UNORDERED_MAP<std::string, cmTarget*> TargetMap;
   TargetMap ImportedTargets;
 
   // Internal policy stack management.
@@ -899,16 +884,8 @@ private:
    */
   cmSourceFile* LinearGetSourceFileWithOutput(const std::string& cname) const;
 
-// A map for fast output to input look up.
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-  typedef std::unordered_map<std::string, cmSourceFile*> OutputToSourceMap;
-#else
-  typedef cmsys::hash_map<std::string, cmSourceFile*> OutputToSourceMap;
-#endif
-#else
-  typedef std::map<std::string, cmSourceFile*> OutputToSourceMap;
-#endif
+  // A map for fast output to input look up.
+  typedef CM_UNORDERED_MAP<std::string, cmSourceFile*> OutputToSourceMap;
   OutputToSourceMap OutputToSource;
 
   void UpdateOutputToSourceMap(std::vector<std::string> const& outputs,

Source/cmTarget.h

@@ -12,6 +12,7 @@
 #include "cmPropertyMap.h"
 #include "cmStateTypes.h"
 #include "cmTargetLinkLibraryType.h"
+#include "cm_unordered_map.hxx"
 
 #include <iosfwd>
 #include <map>
@@ -20,14 +21,6 @@
 #include <utility>
 #include <vector>
 
-#if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-#include <unordered_map>
-#else
-#include <cmsys/hash_map.hxx>
-#endif
-#endif
-
 class cmMakefile;
 class cmSourceFile;
 class cmGlobalGenerator;
@@ -324,15 +317,7 @@ private:
   cmListFileBacktrace Backtrace;
 };
 
-#ifdef CMAKE_BUILD_WITH_CMAKE
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-typedef std::unordered_map<std::string, cmTarget> cmTargets;
-#else
-typedef cmsys::hash_map<std::string, cmTarget> cmTargets;
-#endif
-#else
-typedef std::map<std::string, cmTarget> cmTargets;
-#endif
+typedef CM_UNORDERED_MAP<std::string, cmTarget> cmTargets;
 
 class cmTargetSet : public std::set<std::string>
 {

Source/cm_unordered_map.hxx

@@ -0,0 +1,25 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#ifndef CM_UNORDERED_MAP_HXX
+#define CM_UNORDERED_MAP_HXX
+
+#include <cmConfigure.h>
+
+#if defined(CMake_HAVE_CXX_UNORDERED_MAP)
+
+#include <unordered_map>
+#define CM_UNORDERED_MAP std::unordered_map
+
+#elif defined(CMAKE_BUILD_WITH_CMAKE)
+
+#include <cmsys/hash_map.hxx>
+#define CM_UNORDERED_MAP cmsys::hash_map
+
+#else
+
+#include <map>
+#define CM_UNORDERED_MAP std::map
+
+#endif
+
+#endif

Source/cmake.cxx

@@ -27,6 +27,7 @@
 #if defined(CMAKE_BUILD_WITH_CMAKE)
 #include "cmGraphVizWriter.h"
 #include "cmVariableWatch.h"
+#include "cm_unordered_map.hxx"
 
 #include <cm_jsoncpp_writer.h>
 #endif
@@ -122,11 +123,7 @@ class cmCommand;
 namespace {
 
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX_UNORDERED_MAP
-typedef std::unordered_map<std::string, Json::Value> JsonValueMapType;
-#else
-typedef cmsys::hash_map<std::string, Json::Value> JsonValueMapType;
-#endif
+typedef CM_UNORDERED_MAP<std::string, Json::Value> JsonValueMapType;
 #endif
 
 } // namespace