Source/cmVariableWatch.h

   1 /*=========================================================================
   2
   3   Program:   CMake - Cross-Platform Makefile Generator
   4   Module:    $RCSfile: cmVariableWatch.h,v $
   5   Language:  C++
   6   Date:      $Date: 2007-05-17 21:40:59 $
   7   Version:   $Revision: 1.10 $
   8
   9   Copyright (c) 2002 Kitware, Inc., Insight Consortium.  All rights reserved.
  10   See Copyright.txt or http://www.cmake.org/HTML/Copyright.html for details.
  11
  12      This software is distributed WITHOUT ANY WARRANTY; without even
  13      the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  14      PURPOSE.  See the above copyright notices for more information.
  15
  16 =========================================================================*/
  17 #ifndef cmVariableWatch_h
  18 #define cmVariableWatch_h
  19
  20 #include "cmStandardIncludes.h"
  21
  22 class cmMakefile;
  23
  24 /** \class cmVariableWatch
  25  * \brief Helper class for watching of variable accesses.
  26  *
  27  * Calls function when variable is accessed
  28  */
  29 class cmVariableWatch
  30 {
  31 public:
  32   typedef void (*WatchMethod)(const std::string& variable, int access_type,
  33     void* client_data, const char* newValue, const cmMakefile* mf);
  34
  35   cmVariableWatch();
  36   ~cmVariableWatch();
  37
  38   /**
  39    * Add watch to the variable
  40    */
  41   void AddWatch(const std::string& variable, WatchMethod method,
  42                 void* client_data=0);
  43   void RemoveWatch(const std::string& variable, WatchMethod method);
  44
  45   /**
  46    * This method is called when variable is accessed
  47    */
  48   void VariableAccessed(const std::string& variable, int access_type,
  49     const char* newValue, const cmMakefile* mf) const;
  50
  51   /**
  52    * Different access types.
  53    */
  54   enum
  55     {
  56     VARIABLE_READ_ACCESS = 0,
  57     UNKNOWN_VARIABLE_READ_ACCESS,
  58     UNKNOWN_VARIABLE_DEFINED_ACCESS,
  59     ALLOWED_UNKNOWN_VARIABLE_READ_ACCESS,
  60     VARIABLE_MODIFIED_ACCESS,
  61     VARIABLE_REMOVED_ACCESS,
  62     NO_ACCESS
  63     };
  64
  65   /**
  66    * Return the access as string
  67    */
  68   static const char* GetAccessAsString(int access_type);
  69
  70 protected:
  71   struct Pair
  72   {
  73     WatchMethod Method;
  74     void*        ClientData;
  75     Pair() : Method(0), ClientData(0) {}
  76   };
  77
  78   typedef std::vector< Pair > VectorOfPairs;
  79   typedef std::map<cmStdString, VectorOfPairs > StringToVectorOfPairs;
  80
  81   StringToVectorOfPairs WatchMap;
  82 };
  83
  84
  85 #endif