Source/cmIfCommand.h

   1 /*=========================================================================
   2
   3   Program:   CMake - Cross-Platform Makefile Generator
   4   Module:    $RCSfile: cmIfCommand.h,v $
   5   Language:  C++
   6   Date:      $Date: 2008-01-23 15:27:59 $
   7   Version:   $Revision: 1.45 $
   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 cmIfCommand_h
  18 #define cmIfCommand_h
  19
  20 #include "cmCommand.h"
  21 #include "cmFunctionBlocker.h"
  22
  23 /** \class cmIfFunctionBlocker
  24  * \brief subclass of function blocker
  25  *
  26  *
  27  */
  28 class cmIfFunctionBlocker : public cmFunctionBlocker
  29 {
  30 public:
  31   cmIfFunctionBlocker() {
  32     this->HasRun = false; this->ScopeDepth = 0; this->Executing = false;}
  33   virtual ~cmIfFunctionBlocker() {}
  34   virtual bool IsFunctionBlocked(const cmListFileFunction& lff,
  35                                  cmMakefile &mf,
  36                                  cmExecutionStatus &);
  37   virtual bool ShouldRemove(const cmListFileFunction& lff,
  38                             cmMakefile &mf);
  39   virtual void ScopeEnded(cmMakefile &mf);
  40
  41   std::vector<cmListFileArgument> Args;
  42   std::vector<cmListFileFunction> Functions;
  43   bool IsBlocking;
  44   bool HasRun;
  45   unsigned int ScopeDepth;
  46   bool Executing;
  47 };
  48
  49 /** \class cmIfCommand
  50  * \brief starts an if block
  51  *
  52  * cmIfCommand starts an if block
  53  */
  54 class cmIfCommand : public cmCommand
  55 {
  56 public:
  57   /**
  58    * This is a virtual constructor for the command.
  59    */
  60   virtual cmCommand* Clone()
  61     {
  62     return new cmIfCommand;
  63     }
  64
  65   /**
  66    * This overrides the default InvokeInitialPass implementation.
  67    * It records the arguments before expansion.
  68    */
  69   virtual bool InvokeInitialPass(const std::vector<cmListFileArgument>& args,
  70                                  cmExecutionStatus &);
  71
  72   /**
  73    * This is called when the command is first encountered in
  74    * the CMakeLists.txt file.
  75    */
  76   virtual bool InitialPass(std::vector<std::string> const&,
  77                            cmExecutionStatus &) { return false;};
  78
  79   /**
  80    * The name of the command as specified in CMakeList.txt.
  81    */
  82   virtual const char* GetName() { return "if";}
  83
  84   /**
  85    * Succinct documentation.
  86    */
  87   virtual const char* GetTerseDocumentation()
  88     {
  89     return "Conditionally execute a group of commands.";
  90     }
  91
  92   /**
  93    * This determines if the command is invoked when in script mode.
  94    */
  95   virtual bool IsScriptable() { return true; }
  96
  97   /**
  98    * More documentation.
  99    */
 100   virtual const char* GetFullDocumentation()
 101     {
 102     return
 103       "  if(expression)\n"
 104       "    # then section.\n"
 105       "    COMMAND1(ARGS ...)\n"
 106       "    COMMAND2(ARGS ...)\n"
 107       "    ...\n"
 108       "  elseif(expression2)\n"
 109       "    # elseif section.\n"
 110       "    COMMAND1(ARGS ...)\n"
 111       "    COMMAND2(ARGS ...)\n"
 112       "    ...\n"
 113       "  else(expression)\n"
 114       "    # else section.\n"
 115       "    COMMAND1(ARGS ...)\n"
 116       "    COMMAND2(ARGS ...)\n"
 117       "    ...\n"
 118       "  endif(expression)\n"
 119       "Evaluates the given expression.  If the result is true, the commands "
 120       "in the THEN section are invoked.  Otherwise, the commands in the "
 121       "else section are invoked.  The elseif and else sections are "
 122       "optional. You may have multiple elseif clauses. Note that "
 123       "the same expression must be given to if, and endif.  Long "
 124       "expressions can be used and the order or precedence is that the "
 125       "EXISTS, COMMAND, and DEFINED operators will be evaluated first. "
 126       "Then any EQUAL, LESS, GREATER, STRLESS, STRGREATER, STREQUAL, MATCHES "
 127       "will be evaluated. Then NOT operators and finally AND, OR operators "
 128       "will be evaluated. Possible expressions are:\n"
 129       "  if(variable)\n"
 130       "True if the variable's value is not empty, 0, N, NO, OFF, FALSE, "
 131       "NOTFOUND, or <variable>-NOTFOUND.\n"
 132       "  if(NOT variable)\n"
 133       "True if the variable's value is empty, 0, N, NO, OFF, FALSE, "
 134       "NOTFOUND, or <variable>-NOTFOUND.\n"
 135       "  if(variable1 AND variable2)\n"
 136       "True if both variables would be considered true individually.\n"
 137       "  if(variable1 OR variable2)\n"
 138       "True if either variable would be considered true individually.\n"
 139       "  if(COMMAND command-name)\n"
 140       "True if the given name is a command that can be invoked.\n"
 141       "  if(EXISTS file-name)\n"
 142       "  if(EXISTS directory-name)\n"
 143       "True if the named file or directory exists.  "
 144       "Behavior is well-defined only for full paths.\n"
 145       "  if(file1 IS_NEWER_THAN file2)\n"
 146       "True if file1 is newer than file2 or if one of the two files "
 147       "doesn't exist. "
 148       "Behavior is well-defined only for full paths.\n"
 149       "  if(IS_DIRECTORY directory-name)\n"
 150       "True if the given name is a directory.  "
 151       "Behavior is well-defined only for full paths.\n"
 152       "  if(IS_ABSOLUTE path)\n"
 153       "True if the given path is an absolute path.\n "
 154       "  if(variable MATCHES regex)\n"
 155       "  if(string MATCHES regex)\n"
 156       "True if the given string or variable's value matches the given "
 157       "regular expression.\n"
 158       "  if(variable LESS number)\n"
 159       "  if(string LESS number)\n"
 160       "  if(variable GREATER number)\n"
 161       "  if(string GREATER number)\n"
 162       "  if(variable EQUAL number)\n"
 163       "  if(string EQUAL number)\n"
 164       "True if the given string or variable's value is a valid number and "
 165       "the inequality or equality is true.\n"
 166       "  if(variable STRLESS string)\n"
 167       "  if(string STRLESS string)\n"
 168       "  if(variable STRGREATER string)\n"
 169       "  if(string STRGREATER string)\n"
 170       "  if(variable STREQUAL string)\n"
 171       "  if(string STREQUAL string)\n"
 172       "True if the given string or variable's value is lexicographically "
 173       "less (or greater, or equal) than the string on the right.\n"
 174       "  if(DEFINED variable)\n"
 175       "True if the given variable is defined. It does not matter if the "
 176       "variable is true or false just if it has been set.";
 177     }
 178
 179   // this is a shared function for both If and Else to determine if the
 180   // arguments were valid, and if so, was the response true. If there is
 181   // an error, the errorString will be set.
 182   static bool IsTrue(const std::vector<std::string> &args,
 183     char** errorString, cmMakefile *mf);
 184
 185   // Get a definition from the makefile.  If it doesn't exist,
 186   // return the original string.
 187   static const char* GetVariableOrString(const char* str,
 188                                          const cmMakefile* mf);
 189   static const char* GetVariableOrNumber(const char* str,
 190                                          const cmMakefile* mf);
 191
 192
 193   cmTypeMacro(cmIfCommand, cmCommand);
 194 };
 195
 196
 197 #endif