Add CMAKE_ARGC and CMAKE_ARGV0..N-1 variables (#2828)

For now, these variables are only available in -P script mode.

Source/cmDocumentVariables.cxx

@@ -104,6 +104,22 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
      "file, this variable is not set.", false,
      "Variables that Provide Information");
 
+  cm->DefineProperty
+    ("CMAKE_ARGC", cmProperty::VARIABLE,
+     "Number of command line arguments passed to CMake in script mode. ",
+     "When run in -P script mode, CMake sets this variable to the number "
+     "of command line arguments. See also CMAKE_ARGV0, 1, 2 ... ", false,
+     "Variables that Provide Information");
+
+  cm->DefineProperty
+    ("CMAKE_ARGV0", cmProperty::VARIABLE,
+     "Command line argument passed to CMake in script mode. ",
+     "When run in -P script mode, CMake sets this variable to "
+     "the first command line argument. It then also sets CMAKE_ARGV1, "
+     "CMAKE_ARGV2, ... and so on, up to the number of command line arguments "
+     "given. See also CMAKE_ARGC.", false,
+     "Variables that Provide Information");
+
   cm->DefineProperty
     ("CMAKE_BUILD_TOOL", cmProperty::VARIABLE,
      "Tool used for the actual build process.",

Source/cmMakefile.cxx

@@ -2749,6 +2749,22 @@ void cmMakefile::SetScriptModeFile(const char* scriptfile)
   this->AddDefinition("CMAKE_SCRIPT_MODE_FILE", scriptfile);
 }
 
+void cmMakefile::SetArgcArgv(const std::vector<std::string>& args)
+{
+  cmOStringStream strStream;
+  strStream << args.size();
+  this->AddDefinition("CMAKE_ARGC", strStream.str().c_str());
+  //this->MarkVariableAsUsed("CMAKE_ARGC");
+
+  for (unsigned int t = 0; t < args.size(); ++t)
+  {
+    cmOStringStream tmpStream;
+    tmpStream << "CMAKE_ARGV" << t;
+    this->AddDefinition(tmpStream.str().c_str(), args[t].c_str());
+    //this->MarkVariableAsUsed(tmpStream.str().c_str());
+  }
+}
+
 //----------------------------------------------------------------------------
 cmSourceFile* cmMakefile::GetSource(const char* sourceName)
 {

Source/cmMakefile.h

@@ -417,6 +417,11 @@ public:
    */
   void SetScriptModeFile(const char* scriptfile);
 
+  /**
+   * Set CMAKE_ARGC, CMAKE_ARGV0 ... variables.
+   */
+  void SetArgcArgv(const std::vector<std::string>& args);
+
   //@{
   /**
    * Set/Get the start directory (or output directory). The start directory

Source/cmake.cxx

@@ -462,7 +462,7 @@ bool cmake::SetCacheArgs(const std::vector<std::string>& args)
           }
         }
       std::cerr << "loading initial cache file " << path.c_str() << "\n";
-      this->ReadListFile(path.c_str());
+      this->ReadListFile(args, path.c_str());
       }
     else if(arg.find("-P",0) == 0)
       {
@@ -478,13 +478,13 @@ bool cmake::SetCacheArgs(const std::vector<std::string>& args)
         cmSystemTools::Error("No cmake script provided.");
         return false;
         }
-      this->ReadListFile(path.c_str());
+      this->ReadListFile(args, path.c_str());
       }
     }
   return true;
 }
 
-void cmake::ReadListFile(const char *path)
+void cmake::ReadListFile(const std::vector<std::string>& args, const char *path)
 {
   // if a generator was not yet created, temporarily create one
   cmGlobalGenerator *gg = this->GetGlobalGenerator();
@@ -515,6 +515,8 @@ void cmake::ReadListFile(const char *path)
       std::string file(cmSystemTools::CollapseFullPath(path));
       cmSystemTools::ConvertToUnixSlashes(file);
       lg->GetMakefile()->SetScriptModeFile(file.c_str());
+
+      lg->GetMakefile()->SetArgcArgv(args);
       }
     if (!lg->GetMakefile()->ReadListFile(0, path))
       {
@@ -2203,13 +2205,14 @@ int cmake::ActualConfigure()
 
 void cmake::PreLoadCMakeFiles()
 {
+  std::vector<std::string> args;
   std::string pre_load = this->GetHomeDirectory();
   if ( pre_load.size() > 0 )
     {
     pre_load += "/PreLoad.cmake";
     if ( cmSystemTools::FileExists(pre_load.c_str()) )
       {
-      this->ReadListFile(pre_load.c_str());
+      this->ReadListFile(args, pre_load.c_str());
       }
     }
   pre_load = this->GetHomeOutputDirectory();
@@ -2218,7 +2221,7 @@ void cmake::PreLoadCMakeFiles()
     pre_load += "/PreLoad.cmake";
     if ( cmSystemTools::FileExists(pre_load.c_str()) )
       {
-      this->ReadListFile(pre_load.c_str());
+      this->ReadListFile(args, pre_load.c_str());
       }
     }
 }

Source/cmake.h

@@ -406,7 +406,7 @@ protected:
   bool DoSuppressDevWarnings;
 
   ///! read in a cmake list file to initialize the cache
-  void ReadListFile(const char *path);
+  void ReadListFile(const std::vector<std::string>& args, const char *path);
 
   ///! Check if CMAKE_CACHEFILE_DIR is set. If it is not, delete the log file.
   ///  If it is set, truncate it to 50kb