| /*============================================================================ |
| 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() const { return true; } |
| |
| /** |
| * The name of the command as specified in CMakeList.txt. |
| */ |
| virtual const char* GetName() const {return "cmake_policy";} |
| |
| /** |
| * Succinct documentation. |
| */ |
| virtual const char* GetTerseDocumentation() const |
| { |
| return "Manage CMake Policy settings."; |
| } |
| |
| /** |
| * More documentation. |
| */ |
| virtual const char* GetFullDocumentation() const |
| { |
| 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 |