/*============================================================================ CMake - Cross Platform Makefile Generator Copyright 2000-2009 Kitware, Inc., Insight Software Consortium Distributed under the OSI-approved BSD License (the "License"); see accompanying file Copyright.txt for details. This software is distributed WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the License for more information. ============================================================================*/ #ifndef cmCMakePolicyCommand_h #define cmCMakePolicyCommand_h #include "cmCommand.h" /** \class cmCMakePolicyCommand * \brief Set how CMake should handle policies * * cmCMakePolicyCommand sets how CMake should deal with backwards * compatibility policies. */ class cmCMakePolicyCommand : public cmCommand { public: /** * This is a virtual constructor for the command. */ virtual cmCommand* Clone() { return new cmCMakePolicyCommand; } /** * This is called when the command is first encountered in * the CMakeLists.txt file. */ virtual bool InitialPass(std::vector<std::string> const& args, cmExecutionStatus &status); /** * This determines if the command is invoked when in script mode. */ virtual bool IsScriptable() { return true; } /** * The name of the command as specified in CMakeList.txt. */ virtual const char* GetName() {return "cmake_policy";} /** * Succinct documentation. */ virtual const char* GetTerseDocumentation() { return "Manage CMake Policy settings."; } /** * More documentation. */ virtual const char* GetFullDocumentation() { return "As CMake evolves it is sometimes necessary to change existing " "behavior in order to fix bugs or improve implementations of " "existing features. " "The CMake Policy mechanism is designed to help keep existing projects " "building as new versions of CMake introduce changes in behavior. " "Each new policy (behavioral change) is given an identifier of " "the form \"CMP<NNNN>\" where \"<NNNN>\" is an integer index. " "Documentation associated with each policy describes the OLD and NEW " "behavior and the reason the policy was introduced. " "Projects may set each policy to select the desired behavior. " "When CMake needs to know which behavior to use it checks for " "a setting specified by the project. " "If no setting is available the OLD behavior is assumed and a warning " "is produced requesting that the policy be set.\n" "The cmake_policy command is used to set policies to OLD or NEW " "behavior. " "While setting policies individually is supported, we encourage " "projects to set policies based on CMake versions.\n" " cmake_policy(VERSION major.minor[.patch[.tweak]])\n" "Specify that the current CMake list file is written for the " "given version of CMake. " "All policies introduced in the specified version or earlier " "will be set to use NEW behavior. " "All policies introduced after the specified version will be unset " "(unless variable CMAKE_POLICY_DEFAULT_CMP<NNNN> sets a default). " "This effectively requests behavior preferred as of a given CMake " "version and tells newer CMake versions to warn about their new " "policies. " "The policy version specified must be at least 2.4 or the command " "will report an error. " "In order to get compatibility features supporting versions earlier " "than 2.4 see documentation of policy CMP0001." "\n" " cmake_policy(SET CMP<NNNN> NEW)\n" " cmake_policy(SET CMP<NNNN> OLD)\n" "Tell CMake to use the OLD or NEW behavior for a given policy. " "Projects depending on the old behavior of a given policy may " "silence a policy warning by setting the policy state to OLD. " "Alternatively one may fix the project to work with the new behavior " "and set the policy state to NEW." "\n" " cmake_policy(GET CMP<NNNN> <variable>)\n" "Check whether a given policy is set to OLD or NEW behavior. " "The output variable value will be \"OLD\" or \"NEW\" if the " "policy is set, and empty otherwise." "\n" "CMake keeps policy settings on a stack, so changes made by the " "cmake_policy command affect only the top of the stack. " "A new entry on the policy stack is managed automatically for each " "subdirectory to protect its parents and siblings. " "CMake also manages a new entry for scripts loaded by include() and " "find_package() commands except when invoked with the NO_POLICY_SCOPE " "option (see also policy CMP0011). " "The cmake_policy command provides an interface to manage custom " "entries on the policy stack:\n" " cmake_policy(PUSH)\n" " cmake_policy(POP)\n" "Each PUSH must have a matching POP to erase any changes. " "This is useful to make temporary changes to policy settings." "\n" "Functions and macros record policy settings when they are created " "and use the pre-record policies when they are invoked. " "If the function or macro implementation sets policies, the changes " "automatically propagate up through callers until they reach the " "closest nested policy stack entry." ; } cmTypeMacro(cmCMakePolicyCommand, cmCommand); private: bool HandleSetMode(std::vector<std::string> const& args); bool HandleGetMode(std::vector<std::string> const& args); bool HandleVersionMode(std::vector<std::string> const& args); }; #endif