diff options
Diffstat (limited to 'Modules/CMakePackageConfigHelpers.cmake')
| -rw-r--r-- | Modules/CMakePackageConfigHelpers.cmake | 407 |
1 files changed, 204 insertions, 203 deletions
diff --git a/Modules/CMakePackageConfigHelpers.cmake b/Modules/CMakePackageConfigHelpers.cmake index d5301d7..bcc9bf8 100644 --- a/Modules/CMakePackageConfigHelpers.cmake +++ b/Modules/CMakePackageConfigHelpers.cmake @@ -1,209 +1,210 @@ # Distributed under the OSI-approved BSD 3-Clause License. See accompanying # file Copyright.txt or https://cmake.org/licensing for details. -#.rst: -# CMakePackageConfigHelpers -# ------------------------- -# -# Helpers functions for creating config files that can be included by other -# projects to find and use a package. -# -# Adds the :command:`configure_package_config_file()` and -# :command:`write_basic_package_version_file()` commands. -# -# Generating a Package Configuration File -# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -# -# .. command:: configure_package_config_file -# -# Create a config file for a project:: -# -# configure_package_config_file(<input> <output> -# INSTALL_DESTINATION <path> -# [PATH_VARS <var1> <var2> ... <varN>] -# [NO_SET_AND_CHECK_MACRO] -# [NO_CHECK_REQUIRED_COMPONENTS_MACRO] -# [INSTALL_PREFIX <path>] -# ) -# -# ``configure_package_config_file()`` should be used instead of the plain -# :command:`configure_file()` command when creating the ``<PackageName>Config.cmake`` -# or ``<PackageName>-config.cmake`` file for installing a project or library. -# It helps making the resulting package relocatable by avoiding hardcoded paths -# in the installed ``Config.cmake`` file. -# -# In a ``FooConfig.cmake`` file there may be code like this to make the install -# destinations know to the using project: -# -# .. code-block:: cmake -# -# set(FOO_INCLUDE_DIR "@CMAKE_INSTALL_FULL_INCLUDEDIR@" ) -# set(FOO_DATA_DIR "@CMAKE_INSTALL_PREFIX@/@RELATIVE_DATA_INSTALL_DIR@" ) -# set(FOO_ICONS_DIR "@CMAKE_INSTALL_PREFIX@/share/icons" ) -# #...logic to determine installedPrefix from the own location... -# set(FOO_CONFIG_DIR "${installedPrefix}/@CONFIG_INSTALL_DIR@" ) -# -# All 4 options shown above are not sufficient, since the first 3 hardcode the -# absolute directory locations, and the 4th case works only if the logic to -# determine the ``installedPrefix`` is correct, and if ``CONFIG_INSTALL_DIR`` -# contains a relative path, which in general cannot be guaranteed. This has the -# effect that the resulting ``FooConfig.cmake`` file would work poorly under -# Windows and OSX, where users are used to choose the install location of a -# binary package at install time, independent from how -# :variable:`CMAKE_INSTALL_PREFIX` was set at build/cmake time. -# -# Using ``configure_package_config_file`` helps. If used correctly, it makes -# the resulting ``FooConfig.cmake`` file relocatable. Usage: -# -# 1. write a ``FooConfig.cmake.in`` file as you are used to -# 2. insert a line containing only the string ``@PACKAGE_INIT@`` -# 3. instead of ``set(FOO_DIR "@SOME_INSTALL_DIR@")``, use -# ``set(FOO_DIR "@PACKAGE_SOME_INSTALL_DIR@")`` (this must be after the -# ``@PACKAGE_INIT@`` line) -# 4. instead of using the normal :command:`configure_file()`, use -# ``configure_package_config_file()`` -# -# -# -# The ``<input>`` and ``<output>`` arguments are the input and output file, the -# same way as in :command:`configure_file()`. -# -# The ``<path>`` given to ``INSTALL_DESTINATION`` must be the destination where -# the ``FooConfig.cmake`` file will be installed to. This path can either be -# absolute, or relative to the ``INSTALL_PREFIX`` path. -# -# The variables ``<var1>`` to ``<varN>`` given as ``PATH_VARS`` are the -# variables which contain install destinations. For each of them the macro will -# create a helper variable ``PACKAGE_<var...>``. These helper variables must be -# used in the ``FooConfig.cmake.in`` file for setting the installed location. -# They are calculated by ``configure_package_config_file`` so that they are -# always relative to the installed location of the package. This works both for -# relative and also for absolute locations. For absolute locations it works -# only if the absolute location is a subdirectory of ``INSTALL_PREFIX``. -# -# If the ``INSTALL_PREFIX`` argument is passed, this is used as base path to -# calculate all the relative paths. The ``<path>`` argument must be an absolute -# path. If this argument is not passed, the :variable:`CMAKE_INSTALL_PREFIX` -# variable will be used instead. The default value is good when generating a -# FooConfig.cmake file to use your package from the install tree. When -# generating a FooConfig.cmake file to use your package from the build tree this -# option should be used. -# -# By default ``configure_package_config_file`` also generates two helper macros, -# ``set_and_check()`` and ``check_required_components()`` into the -# ``FooConfig.cmake`` file. -# -# ``set_and_check()`` should be used instead of the normal ``set()`` command for -# setting directories and file locations. Additionally to setting the variable -# it also checks that the referenced file or directory actually exists and fails -# with a ``FATAL_ERROR`` otherwise. This makes sure that the created -# ``FooConfig.cmake`` file does not contain wrong references. -# When using the ``NO_SET_AND_CHECK_MACRO``, this macro is not generated -# into the ``FooConfig.cmake`` file. -# -# ``check_required_components(<PackageName>)`` should be called at the end of -# the ``FooConfig.cmake`` file. This macro checks whether all requested, -# non-optional components have been found, and if this is not the case, sets -# the ``Foo_FOUND`` variable to ``FALSE``, so that the package is considered to -# be not found. It does that by testing the ``Foo_<Component>_FOUND`` -# variables for all requested required components. This macro should be -# called even if the package doesn't provide any components to make sure -# users are not specifying components erroneously. When using the -# ``NO_CHECK_REQUIRED_COMPONENTS_MACRO`` option, this macro is not generated -# into the ``FooConfig.cmake`` file. -# -# For an example see below the documentation for -# :command:`write_basic_package_version_file()`. -# -# Generating a Package Version File -# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -# -# .. command:: write_basic_package_version_file -# -# Create a version file for a project:: -# -# write_basic_package_version_file(<filename> -# [VERSION <major.minor.patch>] -# COMPATIBILITY <AnyNewerVersion|SameMajorVersion|SameMinorVersion|ExactVersion> ) -# -# -# Writes a file for use as ``<PackageName>ConfigVersion.cmake`` file to -# ``<filename>``. See the documentation of :command:`find_package()` for -# details on this. -# -# ``<filename>`` is the output filename, it should be in the build tree. -# ``<major.minor.patch>`` is the version number of the project to be installed. -# -# If no ``VERSION`` is given, the :variable:`PROJECT_VERSION` variable is used. -# If this hasn't been set, it errors out. -# -# The ``COMPATIBILITY`` mode ``AnyNewerVersion`` means that the installed -# package version will be considered compatible if it is newer or exactly the -# same as the requested version. This mode should be used for packages which -# are fully backward compatible, also across major versions. -# If ``SameMajorVersion`` is used instead, then the behaviour differs from -# ``AnyNewerVersion`` in that the major version number must be the same as -# requested, e.g. version 2.0 will not be considered compatible if 1.0 is -# requested. This mode should be used for packages which guarantee backward -# compatibility within the same major version. -# If ``SameMinorVersion`` is used, the behaviour is the same as -# ``SameMajorVersion``, but both major and minor version must be the same as -# requested, e.g version 0.2 will not be compatible if 0.1 is requested. -# If ``ExactVersion`` is used, then the package is only considered compatible if -# the requested version matches exactly its own version number (not considering -# the tweak version). For example, version 1.2.3 of a package is only -# considered compatible to requested version 1.2.3. This mode is for packages -# without compatibility guarantees. -# If your project has more elaborated version matching rules, you will need to -# write your own custom ``ConfigVersion.cmake`` file instead of using this -# macro. -# -# Internally, this macro executes :command:`configure_file()` to create the -# resulting version file. Depending on the ``COMPATIBILITY``, the corresponding -# ``BasicConfigVersion-<COMPATIBILITY>.cmake.in`` file is used. -# Please note that these files are internal to CMake and you should not call -# :command:`configure_file()` on them yourself, but they can be used as starting -# point to create more sophisticted custom ``ConfigVersion.cmake`` files. -# -# Example Generating Package Files -# ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -# -# Example using both :command:`configure_package_config_file` and -# ``write_basic_package_version_file()``: -# -# ``CMakeLists.txt``: -# -# .. code-block:: cmake -# -# set(INCLUDE_INSTALL_DIR include/ ... CACHE ) -# set(LIB_INSTALL_DIR lib/ ... CACHE ) -# set(SYSCONFIG_INSTALL_DIR etc/foo/ ... CACHE ) -# #... -# include(CMakePackageConfigHelpers) -# configure_package_config_file(FooConfig.cmake.in -# ${CMAKE_CURRENT_BINARY_DIR}/FooConfig.cmake -# INSTALL_DESTINATION ${LIB_INSTALL_DIR}/Foo/cmake -# PATH_VARS INCLUDE_INSTALL_DIR SYSCONFIG_INSTALL_DIR) -# write_basic_package_version_file( -# ${CMAKE_CURRENT_BINARY_DIR}/FooConfigVersion.cmake -# VERSION 1.2.3 -# COMPATIBILITY SameMajorVersion ) -# install(FILES ${CMAKE_CURRENT_BINARY_DIR}/FooConfig.cmake -# ${CMAKE_CURRENT_BINARY_DIR}/FooConfigVersion.cmake -# DESTINATION ${LIB_INSTALL_DIR}/Foo/cmake ) -# -# ``FooConfig.cmake.in``: -# -# :: -# -# set(FOO_VERSION x.y.z) -# ... -# @PACKAGE_INIT@ -# ... -# set_and_check(FOO_INCLUDE_DIR "@PACKAGE_INCLUDE_INSTALL_DIR@") -# set_and_check(FOO_SYSCONFIG_DIR "@PACKAGE_SYSCONFIG_INSTALL_DIR@") -# -# check_required_components(Foo) +#[=======================================================================[.rst: +CMakePackageConfigHelpers +------------------------- + +Helpers functions for creating config files that can be included by other +projects to find and use a package. + +Adds the :command:`configure_package_config_file()` and +:command:`write_basic_package_version_file()` commands. + +Generating a Package Configuration File +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. command:: configure_package_config_file + + Create a config file for a project:: + + configure_package_config_file(<input> <output> + INSTALL_DESTINATION <path> + [PATH_VARS <var1> <var2> ... <varN>] + [NO_SET_AND_CHECK_MACRO] + [NO_CHECK_REQUIRED_COMPONENTS_MACRO] + [INSTALL_PREFIX <path>] + ) + +``configure_package_config_file()`` should be used instead of the plain +:command:`configure_file()` command when creating the ``<PackageName>Config.cmake`` +or ``<PackageName>-config.cmake`` file for installing a project or library. +It helps making the resulting package relocatable by avoiding hardcoded paths +in the installed ``Config.cmake`` file. + +In a ``FooConfig.cmake`` file there may be code like this to make the install +destinations know to the using project: + +.. code-block:: cmake + + set(FOO_INCLUDE_DIR "@CMAKE_INSTALL_FULL_INCLUDEDIR@" ) + set(FOO_DATA_DIR "@CMAKE_INSTALL_PREFIX@/@RELATIVE_DATA_INSTALL_DIR@" ) + set(FOO_ICONS_DIR "@CMAKE_INSTALL_PREFIX@/share/icons" ) + #...logic to determine installedPrefix from the own location... + set(FOO_CONFIG_DIR "${installedPrefix}/@CONFIG_INSTALL_DIR@" ) + +All 4 options shown above are not sufficient, since the first 3 hardcode the +absolute directory locations, and the 4th case works only if the logic to +determine the ``installedPrefix`` is correct, and if ``CONFIG_INSTALL_DIR`` +contains a relative path, which in general cannot be guaranteed. This has the +effect that the resulting ``FooConfig.cmake`` file would work poorly under +Windows and OSX, where users are used to choose the install location of a +binary package at install time, independent from how +:variable:`CMAKE_INSTALL_PREFIX` was set at build/cmake time. + +Using ``configure_package_config_file`` helps. If used correctly, it makes +the resulting ``FooConfig.cmake`` file relocatable. Usage: + +1. write a ``FooConfig.cmake.in`` file as you are used to +2. insert a line containing only the string ``@PACKAGE_INIT@`` +3. instead of ``set(FOO_DIR "@SOME_INSTALL_DIR@")``, use + ``set(FOO_DIR "@PACKAGE_SOME_INSTALL_DIR@")`` (this must be after the + ``@PACKAGE_INIT@`` line) +4. instead of using the normal :command:`configure_file()`, use + ``configure_package_config_file()`` + + + +The ``<input>`` and ``<output>`` arguments are the input and output file, the +same way as in :command:`configure_file()`. + +The ``<path>`` given to ``INSTALL_DESTINATION`` must be the destination where +the ``FooConfig.cmake`` file will be installed to. This path can either be +absolute, or relative to the ``INSTALL_PREFIX`` path. + +The variables ``<var1>`` to ``<varN>`` given as ``PATH_VARS`` are the +variables which contain install destinations. For each of them the macro will +create a helper variable ``PACKAGE_<var...>``. These helper variables must be +used in the ``FooConfig.cmake.in`` file for setting the installed location. +They are calculated by ``configure_package_config_file`` so that they are +always relative to the installed location of the package. This works both for +relative and also for absolute locations. For absolute locations it works +only if the absolute location is a subdirectory of ``INSTALL_PREFIX``. + +If the ``INSTALL_PREFIX`` argument is passed, this is used as base path to +calculate all the relative paths. The ``<path>`` argument must be an absolute +path. If this argument is not passed, the :variable:`CMAKE_INSTALL_PREFIX` +variable will be used instead. The default value is good when generating a +FooConfig.cmake file to use your package from the install tree. When +generating a FooConfig.cmake file to use your package from the build tree this +option should be used. + +By default ``configure_package_config_file`` also generates two helper macros, +``set_and_check()`` and ``check_required_components()`` into the +``FooConfig.cmake`` file. + +``set_and_check()`` should be used instead of the normal ``set()`` command for +setting directories and file locations. Additionally to setting the variable +it also checks that the referenced file or directory actually exists and fails +with a ``FATAL_ERROR`` otherwise. This makes sure that the created +``FooConfig.cmake`` file does not contain wrong references. +When using the ``NO_SET_AND_CHECK_MACRO``, this macro is not generated +into the ``FooConfig.cmake`` file. + +``check_required_components(<PackageName>)`` should be called at the end of +the ``FooConfig.cmake`` file. This macro checks whether all requested, +non-optional components have been found, and if this is not the case, sets +the ``Foo_FOUND`` variable to ``FALSE``, so that the package is considered to +be not found. It does that by testing the ``Foo_<Component>_FOUND`` +variables for all requested required components. This macro should be +called even if the package doesn't provide any components to make sure +users are not specifying components erroneously. When using the +``NO_CHECK_REQUIRED_COMPONENTS_MACRO`` option, this macro is not generated +into the ``FooConfig.cmake`` file. + +For an example see below the documentation for +:command:`write_basic_package_version_file()`. + +Generating a Package Version File +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +.. command:: write_basic_package_version_file + + Create a version file for a project:: + + write_basic_package_version_file(<filename> + [VERSION <major.minor.patch>] + COMPATIBILITY <AnyNewerVersion|SameMajorVersion|SameMinorVersion|ExactVersion> ) + + +Writes a file for use as ``<PackageName>ConfigVersion.cmake`` file to +``<filename>``. See the documentation of :command:`find_package()` for +details on this. + +``<filename>`` is the output filename, it should be in the build tree. +``<major.minor.patch>`` is the version number of the project to be installed. + +If no ``VERSION`` is given, the :variable:`PROJECT_VERSION` variable is used. +If this hasn't been set, it errors out. + +The ``COMPATIBILITY`` mode ``AnyNewerVersion`` means that the installed +package version will be considered compatible if it is newer or exactly the +same as the requested version. This mode should be used for packages which +are fully backward compatible, also across major versions. +If ``SameMajorVersion`` is used instead, then the behaviour differs from +``AnyNewerVersion`` in that the major version number must be the same as +requested, e.g. version 2.0 will not be considered compatible if 1.0 is +requested. This mode should be used for packages which guarantee backward +compatibility within the same major version. +If ``SameMinorVersion`` is used, the behaviour is the same as +``SameMajorVersion``, but both major and minor version must be the same as +requested, e.g version 0.2 will not be compatible if 0.1 is requested. +If ``ExactVersion`` is used, then the package is only considered compatible if +the requested version matches exactly its own version number (not considering +the tweak version). For example, version 1.2.3 of a package is only +considered compatible to requested version 1.2.3. This mode is for packages +without compatibility guarantees. +If your project has more elaborated version matching rules, you will need to +write your own custom ``ConfigVersion.cmake`` file instead of using this +macro. + +Internally, this macro executes :command:`configure_file()` to create the +resulting version file. Depending on the ``COMPATIBILITY``, the corresponding +``BasicConfigVersion-<COMPATIBILITY>.cmake.in`` file is used. +Please note that these files are internal to CMake and you should not call +:command:`configure_file()` on them yourself, but they can be used as starting +point to create more sophisticted custom ``ConfigVersion.cmake`` files. + +Example Generating Package Files +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Example using both :command:`configure_package_config_file` and +``write_basic_package_version_file()``: + +``CMakeLists.txt``: + +.. code-block:: cmake + + set(INCLUDE_INSTALL_DIR include/ ... CACHE ) + set(LIB_INSTALL_DIR lib/ ... CACHE ) + set(SYSCONFIG_INSTALL_DIR etc/foo/ ... CACHE ) + #... + include(CMakePackageConfigHelpers) + configure_package_config_file(FooConfig.cmake.in + ${CMAKE_CURRENT_BINARY_DIR}/FooConfig.cmake + INSTALL_DESTINATION ${LIB_INSTALL_DIR}/Foo/cmake + PATH_VARS INCLUDE_INSTALL_DIR SYSCONFIG_INSTALL_DIR) + write_basic_package_version_file( + ${CMAKE_CURRENT_BINARY_DIR}/FooConfigVersion.cmake + VERSION 1.2.3 + COMPATIBILITY SameMajorVersion ) + install(FILES ${CMAKE_CURRENT_BINARY_DIR}/FooConfig.cmake + ${CMAKE_CURRENT_BINARY_DIR}/FooConfigVersion.cmake + DESTINATION ${LIB_INSTALL_DIR}/Foo/cmake ) + +``FooConfig.cmake.in``: + +:: + + set(FOO_VERSION x.y.z) + ... + @PACKAGE_INIT@ + ... + set_and_check(FOO_INCLUDE_DIR "@PACKAGE_INCLUDE_INSTALL_DIR@") + set_and_check(FOO_SYSCONFIG_DIR "@PACKAGE_SYSCONFIG_INSTALL_DIR@") + + check_required_components(Foo) +#]=======================================================================] include(WriteBasicConfigVersionFile) |