diff options
| -rw-r--r-- | Help/manual/cmake-developer.7.rst | 188 | ||||
| -rw-r--r-- | Modules/readme.txt | 188 |
2 files changed, 188 insertions, 188 deletions
diff --git a/Help/manual/cmake-developer.7.rst b/Help/manual/cmake-developer.7.rst index 37e4e3f..8052e27 100644 --- a/Help/manual/cmake-developer.7.rst +++ b/Help/manual/cmake-developer.7.rst @@ -16,3 +16,191 @@ Help Modules ======= + +Note to authors of FindXxx.cmake files + +We would like all FindXxx.cmake files to produce consistent variable names. + +Please use the following consistent variable names for general use. + +Xxx_INCLUDE_DIRS The final set of include directories listed in one variable for use by client code. + This should not be a cache entry. +Xxx_LIBRARIES The libraries to link against to use Xxx. These should include full paths. + This should not be a cache entry. +Xxx_DEFINITIONS Definitions to use when compiling code that uses Xxx. This really shouldn't include options such + as (-DHAS_JPEG)that a client source-code file uses to decide whether to #include <jpeg.h> +Xxx_EXECUTABLE Where to find the Xxx tool. +Xxx_Yyy_EXECUTABLE Where to find the Yyy tool that comes with Xxx. +Xxx_LIBRARY_DIRS Optionally, the final set of library directories listed in one variable for use by client code. + This should not be a cache entry. +Xxx_ROOT_DIR Where to find the base directory of Xxx. +Xxx_VERSION_Yy Expect Version Yy if true. Make sure at most one of these is ever true. +Xxx_WRAP_Yy If False, do not try to use the relevant CMake wrapping command. +Xxx_Yy_FOUND If False, optional Yy part of Xxx sytem is not available. +Xxx_FOUND Set to false, or undefined, if we haven't found, or don't want to use Xxx. +Xxx_NOT_FOUND_MESSAGE Should be set by config-files in the case that it has set Xxx_FOUND to FALSE. + The contained message will be printed by the find_package() command and by + find_package_handle_standard_args() to inform the user about the problem. +Xxx_RUNTIME_LIBRARY_DIRS Optionally, the runtime library search path for use when running an executable linked to + shared libraries. + The list should be used by user code to create the PATH on windows or LD_LIBRARY_PATH on unix. + This should not be a cache entry. +Xxx_VERSION_STRING A human-readable string containing the version of the package found, if any. +Xxx_VERSION_MAJOR The major version of the package found, if any. +Xxx_VERSION_MINOR The minor version of the package found, if any. +Xxx_VERSION_PATCH The patch version of the package found, if any. + +You do not have to provide all of the above variables. You should provide Xxx_FOUND under most circumstances. +If Xxx is a library, then Xxx_LIBRARIES, should also be defined, and Xxx_INCLUDE_DIRS should usually be +defined (I guess libm.a might be an exception) + +The following names should not usually be used in CMakeLists.txt files, but they may be usefully modified in +users' CMake Caches to control stuff. + +Xxx_LIBRARY Name of Xxx Library. A User may set this and Xxx_INCLUDE_DIR to ignore to force non-use of Xxx. +Xxx_Yy_LIBRARY Name of Yy library that is part of the Xxx system. It may or may not be required to use Xxx. +Xxx_INCLUDE_DIR Where to find xxx.h, etc. (Xxx_INCLUDE_PATH was considered bad because a path includes an + actual filename.) +Xxx_Yy_INCLUDE_DIR Where to find xxx_yy.h, etc. + +For tidiness's sake, try to keep as many options as possible out of the cache, leaving at least one option which can be +used to disable use of the module, or locate a not-found library (e.g. Xxx_ROOT_DIR). +For the same reason, mark most cache options as advanced. + +If you need other commands to do special things then it should still begin with Xxx_. This gives a sort of namespace +effect and keeps things tidy for the user. You should put comments describing all the exported settings, plus +descriptions of any the users can use to control stuff. + +You really should also provide backwards compatibility any old settings that were actually in use. +Make sure you comment them as deprecated, so that no-one starts using them. + +To add a module to the CMake documentation, follow these steps: + +1. Add file ``Help/module/FindXxx.rst`` containing just the line:: + + .. cmake-module:: ../../Modules/FindXxx.cmake + +2. Modify ``Help/manual/cmake-modules.7.rst`` to reference the module in the + toctree directive as:: + + /module/FindXxx + + Keep the toctree in sorted order! + +3. Add to the top of ``Modules/FindXxx.cmake`` a #-comment of the form:: + + #.rst: + # FindXxx + # ------- + # + # ...reStructuredText documentation of module... + + Comment blocks starting with the line ``#.rst:`` may appear anywhere + in the file. + +For example:: + + #.rst + # FindXxx + # ------- + # + # This is a cool module. + # This module does really cool stuff. + # It can do even more than you think. + # + # It even needs two paragraphs to tell you about it. + # And it defines the following variables: + # + # * VAR_COOL: this is great isn't it? + # * VAR_REALLY_COOL: cool right? + +Test the documentation formatting by running "cmake --help-module FindXxx", +and ideally by enabling the SPHINX_HTML and SPHINX_MAN options to build the +documentation. Edit the comments until generated documentation looks +satisfactory. + +To have a .cmake file in this directory NOT show up in the modules +documentation, simply leave out the ``Help/module/<module>.rst`` file and the +``Help/manual/cmake-modules.7.rst`` toctree entry. + +After the documentation, leave a *BLANK* line, and then add a +copyright and licence notice block like this one: + +#============================================================================= +# Copyright 2009-2011 Your Name +# +# 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. +#============================================================================= +# (To distribute this file outside of CMake, substitute the full +# License text for the above reference.) + +The layout of the notice block is strictly enforced by the ModuleNotices test. +Only the year range and name may be changed freely. + +A FindXxx.cmake module will typically be loaded by the command + + FIND_PACKAGE(Xxx [major[.minor[.patch[.tweak]]]] [EXACT] + [QUIET] [[REQUIRED|COMPONENTS] [components...]]) + +If any version numbers are given to the command it will set the +following variables before loading the module: + + Xxx_FIND_VERSION = full requested version string + Xxx_FIND_VERSION_MAJOR = major version if requested, else 0 + Xxx_FIND_VERSION_MINOR = minor version if requested, else 0 + Xxx_FIND_VERSION_PATCH = patch version if requested, else 0 + Xxx_FIND_VERSION_TWEAK = tweak version if requested, else 0 + Xxx_FIND_VERSION_COUNT = number of version components, 0 to 4 + Xxx_FIND_VERSION_EXACT = true if EXACT option was given + +If the find module supports versioning it should locate a version of +the package that is compatible with the version requested. If a +compatible version of the package cannot be found the module should +not report success. The version of the package found should be stored +in "Xxx_VERSION..." version variables documented by the module. + +If the QUIET option is given to the command it will set the variable +Xxx_FIND_QUIETLY to true before loading the FindXxx.cmake module. If +this variable is set the module should not complain about not being +able to find the package. If the +REQUIRED option is given to the command it will set the variable +Xxx_FIND_REQUIRED to true before loading the FindXxx.cmake module. If +this variable is set the module should issue a FATAL_ERROR if the +package cannot be found. +If neither the QUIET nor REQUIRED options are given then the +FindXxx.cmake module should look for the package and complain without +error if the module is not found. + +FIND_PACKAGE() will set the variable CMAKE_FIND_PACKAGE_NAME to +contain the actual name of the package. + +A package can provide sub-components. +Those components can be listed after the COMPONENTS (or REQUIRED) +or OPTIONAL_COMPONENTS keywords. The set of all listed components will be +specified in a Xxx_FIND_COMPONENTS variable. +For each package-specific component, say Yyy, a variable Xxx_FIND_REQUIRED_Yyy +will be set to true if it listed after COMPONENTS and it will be set to false +if it was listed after OPTIONAL_COMPONENTS. +Using those variables a FindXxx.cmake module and also a XxxConfig.cmake package +configuration file can determine whether and which components have been requested, +and whether they were requested as required or as optional. +For each of the requested components a Xxx_Yyy_FOUND variable should be set +accordingly. +The per-package Xxx_FOUND variable should be only set to true if all requested +required components have been found. A missing optional component should not +keep the Xxx_FOUND variable from being set to true. +If the package provides Xxx_INCLUDE_DIRS and Xxx_LIBRARIES variables, the include +dirs and libraries for all components which were requested and which have been +found should be added to those two variables. + +To get this behaviour you can use the FIND_PACKAGE_HANDLE_STANDARD_ARGS() +macro, as an example see FindJPEG.cmake. + +For internal implementation, it's a generally accepted convention that variables starting with +underscore are for temporary use only. (variable starting with an underscore +are not intended as a reserved prefix). diff --git a/Modules/readme.txt b/Modules/readme.txt index 2593b4f..7d7d397 100644 --- a/Modules/readme.txt +++ b/Modules/readme.txt @@ -1,190 +1,2 @@ For more information about how to contribute modules to CMake, see this page: http://www.itk.org/Wiki/CMake:Module_Maintainers - -Note to authors of FindXxx.cmake files - -We would like all FindXxx.cmake files to produce consistent variable names. - -Please use the following consistent variable names for general use. - -Xxx_INCLUDE_DIRS The final set of include directories listed in one variable for use by client code. - This should not be a cache entry. -Xxx_LIBRARIES The libraries to link against to use Xxx. These should include full paths. - This should not be a cache entry. -Xxx_DEFINITIONS Definitions to use when compiling code that uses Xxx. This really shouldn't include options such - as (-DHAS_JPEG)that a client source-code file uses to decide whether to #include <jpeg.h> -Xxx_EXECUTABLE Where to find the Xxx tool. -Xxx_Yyy_EXECUTABLE Where to find the Yyy tool that comes with Xxx. -Xxx_LIBRARY_DIRS Optionally, the final set of library directories listed in one variable for use by client code. - This should not be a cache entry. -Xxx_ROOT_DIR Where to find the base directory of Xxx. -Xxx_VERSION_Yy Expect Version Yy if true. Make sure at most one of these is ever true. -Xxx_WRAP_Yy If False, do not try to use the relevant CMake wrapping command. -Xxx_Yy_FOUND If False, optional Yy part of Xxx sytem is not available. -Xxx_FOUND Set to false, or undefined, if we haven't found, or don't want to use Xxx. -Xxx_NOT_FOUND_MESSAGE Should be set by config-files in the case that it has set Xxx_FOUND to FALSE. - The contained message will be printed by the find_package() command and by - find_package_handle_standard_args() to inform the user about the problem. -Xxx_RUNTIME_LIBRARY_DIRS Optionally, the runtime library search path for use when running an executable linked to - shared libraries. - The list should be used by user code to create the PATH on windows or LD_LIBRARY_PATH on unix. - This should not be a cache entry. -Xxx_VERSION_STRING A human-readable string containing the version of the package found, if any. -Xxx_VERSION_MAJOR The major version of the package found, if any. -Xxx_VERSION_MINOR The minor version of the package found, if any. -Xxx_VERSION_PATCH The patch version of the package found, if any. - -You do not have to provide all of the above variables. You should provide Xxx_FOUND under most circumstances. -If Xxx is a library, then Xxx_LIBRARIES, should also be defined, and Xxx_INCLUDE_DIRS should usually be -defined (I guess libm.a might be an exception) - -The following names should not usually be used in CMakeLists.txt files, but they may be usefully modified in -users' CMake Caches to control stuff. - -Xxx_LIBRARY Name of Xxx Library. A User may set this and Xxx_INCLUDE_DIR to ignore to force non-use of Xxx. -Xxx_Yy_LIBRARY Name of Yy library that is part of the Xxx system. It may or may not be required to use Xxx. -Xxx_INCLUDE_DIR Where to find xxx.h, etc. (Xxx_INCLUDE_PATH was considered bad because a path includes an - actual filename.) -Xxx_Yy_INCLUDE_DIR Where to find xxx_yy.h, etc. - -For tidiness's sake, try to keep as many options as possible out of the cache, leaving at least one option which can be -used to disable use of the module, or locate a not-found library (e.g. Xxx_ROOT_DIR). -For the same reason, mark most cache options as advanced. - -If you need other commands to do special things then it should still begin with Xxx_. This gives a sort of namespace -effect and keeps things tidy for the user. You should put comments describing all the exported settings, plus -descriptions of any the users can use to control stuff. - -You really should also provide backwards compatibility any old settings that were actually in use. -Make sure you comment them as deprecated, so that no-one starts using them. - -To add a module to the CMake documentation, follow these steps: - -1. Add file ``Help/module/FindXxx.rst`` containing just the line:: - - .. cmake-module:: ../../Modules/FindXxx.cmake - -2. Modify ``Help/manual/cmake-modules.7.rst`` to reference the module in the - toctree directive as:: - - /module/FindXxx - - Keep the toctree in sorted order! - -3. Add to the top of ``Modules/FindXxx.cmake`` a #-comment of the form:: - - #.rst: - # FindXxx - # ------- - # - # ...reStructuredText documentation of module... - - Comment blocks starting with the line ``#.rst:`` may appear anywhere - in the file. - -For example:: - - #.rst - # FindXxx - # ------- - # - # This is a cool module. - # This module does really cool stuff. - # It can do even more than you think. - # - # It even needs two paragraphs to tell you about it. - # And it defines the following variables: - # - # * VAR_COOL: this is great isn't it? - # * VAR_REALLY_COOL: cool right? - -Test the documentation formatting by running "cmake --help-module FindXxx", -and ideally by enabling the SPHINX_HTML and SPHINX_MAN options to build the -documentation. Edit the comments until generated documentation looks -satisfactory. - -To have a .cmake file in this directory NOT show up in the modules -documentation, simply leave out the ``Help/module/<module>.rst`` file and the -``Help/manual/cmake-modules.7.rst`` toctree entry. - -After the documentation, leave a *BLANK* line, and then add a -copyright and licence notice block like this one: - -#============================================================================= -# Copyright 2009-2011 Your Name -# -# 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. -#============================================================================= -# (To distribute this file outside of CMake, substitute the full -# License text for the above reference.) - -The layout of the notice block is strictly enforced by the ModuleNotices test. -Only the year range and name may be changed freely. - -A FindXxx.cmake module will typically be loaded by the command - - FIND_PACKAGE(Xxx [major[.minor[.patch[.tweak]]]] [EXACT] - [QUIET] [[REQUIRED|COMPONENTS] [components...]]) - -If any version numbers are given to the command it will set the -following variables before loading the module: - - Xxx_FIND_VERSION = full requested version string - Xxx_FIND_VERSION_MAJOR = major version if requested, else 0 - Xxx_FIND_VERSION_MINOR = minor version if requested, else 0 - Xxx_FIND_VERSION_PATCH = patch version if requested, else 0 - Xxx_FIND_VERSION_TWEAK = tweak version if requested, else 0 - Xxx_FIND_VERSION_COUNT = number of version components, 0 to 4 - Xxx_FIND_VERSION_EXACT = true if EXACT option was given - -If the find module supports versioning it should locate a version of -the package that is compatible with the version requested. If a -compatible version of the package cannot be found the module should -not report success. The version of the package found should be stored -in "Xxx_VERSION..." version variables documented by the module. - -If the QUIET option is given to the command it will set the variable -Xxx_FIND_QUIETLY to true before loading the FindXxx.cmake module. If -this variable is set the module should not complain about not being -able to find the package. If the -REQUIRED option is given to the command it will set the variable -Xxx_FIND_REQUIRED to true before loading the FindXxx.cmake module. If -this variable is set the module should issue a FATAL_ERROR if the -package cannot be found. -If neither the QUIET nor REQUIRED options are given then the -FindXxx.cmake module should look for the package and complain without -error if the module is not found. - -FIND_PACKAGE() will set the variable CMAKE_FIND_PACKAGE_NAME to -contain the actual name of the package. - -A package can provide sub-components. -Those components can be listed after the COMPONENTS (or REQUIRED) -or OPTIONAL_COMPONENTS keywords. The set of all listed components will be -specified in a Xxx_FIND_COMPONENTS variable. -For each package-specific component, say Yyy, a variable Xxx_FIND_REQUIRED_Yyy -will be set to true if it listed after COMPONENTS and it will be set to false -if it was listed after OPTIONAL_COMPONENTS. -Using those variables a FindXxx.cmake module and also a XxxConfig.cmake package -configuration file can determine whether and which components have been requested, -and whether they were requested as required or as optional. -For each of the requested components a Xxx_Yyy_FOUND variable should be set -accordingly. -The per-package Xxx_FOUND variable should be only set to true if all requested -required components have been found. A missing optional component should not -keep the Xxx_FOUND variable from being set to true. -If the package provides Xxx_INCLUDE_DIRS and Xxx_LIBRARIES variables, the include -dirs and libraries for all components which were requested and which have been -found should be added to those two variables. - -To get this behaviour you can use the FIND_PACKAGE_HANDLE_STANDARD_ARGS() -macro, as an example see FindJPEG.cmake. - -For internal implementation, it's a generally accepted convention that variables starting with -underscore are for temporary use only. (variable starting with an underscore -are not intended as a reserved prefix). |