CMake/Modules/FindPackageHandleStandardArgs.cmake
Brad King 58b2d760ee Modules: Format documentation to avoid over-long preformatted lines
Convert several preformatted code block literals that enumerate lists of
options or variables to use reST definition lists instead.  Manually
wrap other long lines in code blocks.
2014-10-22 15:52:31 -04:00

383 lines
14 KiB
CMake

#.rst:
# FindPackageHandleStandardArgs
# -----------------------------
#
#
#
# FIND_PACKAGE_HANDLE_STANDARD_ARGS(<name> ... )
#
# This function is intended to be used in FindXXX.cmake modules files.
# It handles the REQUIRED, QUIET and version-related arguments to
# find_package(). It also sets the <packagename>_FOUND variable. The
# package is considered found if all variables <var1>... listed contain
# valid results, e.g. valid filepaths.
#
# There are two modes of this function. The first argument in both
# modes is the name of the Find-module where it is called (in original
# casing).
#
# The first simple mode looks like this:
#
# ::
#
# FIND_PACKAGE_HANDLE_STANDARD_ARGS(<name>
# (DEFAULT_MSG|"Custom failure message") <var1>...<varN> )
#
# If the variables <var1> to <varN> are all valid, then
# <UPPERCASED_NAME>_FOUND will be set to TRUE. If DEFAULT_MSG is given
# as second argument, then the function will generate itself useful
# success and error messages. You can also supply a custom error
# message for the failure case. This is not recommended.
#
# The second mode is more powerful and also supports version checking:
#
# ::
#
# FIND_PACKAGE_HANDLE_STANDARD_ARGS(NAME
# [FOUND_VAR <resultVar>]
# [REQUIRED_VARS <var1>...<varN>]
# [VERSION_VAR <versionvar>]
# [HANDLE_COMPONENTS]
# [CONFIG_MODE]
# [FAIL_MESSAGE "Custom failure message"] )
#
# In this mode, the name of the result-variable can be set either to
# either <UPPERCASED_NAME>_FOUND or <OriginalCase_Name>_FOUND using the
# FOUND_VAR option. Other names for the result-variable are not
# allowed. So for a Find-module named FindFooBar.cmake, the two
# possible names are FooBar_FOUND and FOOBAR_FOUND. It is recommended
# to use the original case version. If the FOUND_VAR option is not
# used, the default is <UPPERCASED_NAME>_FOUND.
#
# As in the simple mode, if <var1> through <varN> are all valid,
# <packagename>_FOUND will be set to TRUE. After REQUIRED_VARS the
# variables which are required for this package are listed. Following
# VERSION_VAR the name of the variable can be specified which holds the
# version of the package which has been found. If this is done, this
# version will be checked against the (potentially) specified required
# version used in the find_package() call. The EXACT keyword is also
# handled. The default messages include information about the required
# version and the version which has been actually found, both if the
# version is ok or not. If the package supports components, use the
# HANDLE_COMPONENTS option to enable handling them. In this case,
# find_package_handle_standard_args() will report which components have
# been found and which are missing, and the <packagename>_FOUND variable
# will be set to FALSE if any of the required components (i.e. not the
# ones listed after OPTIONAL_COMPONENTS) are missing. Use the option
# CONFIG_MODE if your FindXXX.cmake module is a wrapper for a
# find_package(... NO_MODULE) call. In this case VERSION_VAR will be
# set to <NAME>_VERSION and the macro will automatically check whether
# the Config module was found. Via FAIL_MESSAGE a custom failure
# message can be specified, if this is not used, the default message
# will be displayed.
#
# Example for mode 1:
#
# ::
#
# find_package_handle_standard_args(LibXml2 DEFAULT_MSG
# LIBXML2_LIBRARY LIBXML2_INCLUDE_DIR)
#
#
#
# LibXml2 is considered to be found, if both LIBXML2_LIBRARY and
# LIBXML2_INCLUDE_DIR are valid. Then also LIBXML2_FOUND is set to
# TRUE. If it is not found and REQUIRED was used, it fails with
# FATAL_ERROR, independent whether QUIET was used or not. If it is
# found, success will be reported, including the content of <var1>. On
# repeated Cmake runs, the same message won't be printed again.
#
# Example for mode 2:
#
# ::
#
# find_package_handle_standard_args(LibXslt
# FOUND_VAR LibXslt_FOUND
# REQUIRED_VARS LibXslt_LIBRARIES LibXslt_INCLUDE_DIRS
# VERSION_VAR LibXslt_VERSION_STRING)
#
# In this case, LibXslt is considered to be found if the variable(s)
# listed after REQUIRED_VAR are all valid, i.e. LibXslt_LIBRARIES and
# LibXslt_INCLUDE_DIRS in this case. The result will then be stored in
# LibXslt_FOUND . Also the version of LibXslt will be checked by using
# the version contained in LibXslt_VERSION_STRING. Since no
# FAIL_MESSAGE is given, the default messages will be printed.
#
# Another example for mode 2:
#
# ::
#
# find_package(Automoc4 QUIET NO_MODULE HINTS /opt/automoc4)
# find_package_handle_standard_args(Automoc4 CONFIG_MODE)
#
# In this case, FindAutmoc4.cmake wraps a call to find_package(Automoc4
# NO_MODULE) and adds an additional search directory for automoc4. Here
# the result will be stored in AUTOMOC4_FOUND. The following
# FIND_PACKAGE_HANDLE_STANDARD_ARGS() call produces a proper
# success/error message.
#=============================================================================
# Copyright 2007-2009 Kitware, Inc.
#
# 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.)
include(${CMAKE_CURRENT_LIST_DIR}/FindPackageMessage.cmake)
include(${CMAKE_CURRENT_LIST_DIR}/CMakeParseArguments.cmake)
# internal helper macro
macro(_FPHSA_FAILURE_MESSAGE _msg)
if (${_NAME}_FIND_REQUIRED)
message(FATAL_ERROR "${_msg}")
else ()
if (NOT ${_NAME}_FIND_QUIETLY)
message(STATUS "${_msg}")
endif ()
endif ()
endmacro()
# internal helper macro to generate the failure message when used in CONFIG_MODE:
macro(_FPHSA_HANDLE_FAILURE_CONFIG_MODE)
# <name>_CONFIG is set, but FOUND is false, this means that some other of the REQUIRED_VARS was not found:
if(${_NAME}_CONFIG)
_FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE}: missing: ${MISSING_VARS} (found ${${_NAME}_CONFIG} ${VERSION_MSG})")
else()
# If _CONSIDERED_CONFIGS is set, the config-file has been found, but no suitable version.
# List them all in the error message:
if(${_NAME}_CONSIDERED_CONFIGS)
set(configsText "")
list(LENGTH ${_NAME}_CONSIDERED_CONFIGS configsCount)
math(EXPR configsCount "${configsCount} - 1")
foreach(currentConfigIndex RANGE ${configsCount})
list(GET ${_NAME}_CONSIDERED_CONFIGS ${currentConfigIndex} filename)
list(GET ${_NAME}_CONSIDERED_VERSIONS ${currentConfigIndex} version)
set(configsText "${configsText} ${filename} (version ${version})\n")
endforeach()
if (${_NAME}_NOT_FOUND_MESSAGE)
set(configsText "${configsText} Reason given by package: ${${_NAME}_NOT_FOUND_MESSAGE}\n")
endif()
_FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE} ${VERSION_MSG}, checked the following files:\n${configsText}")
else()
# Simple case: No Config-file was found at all:
_FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE}: found neither ${_NAME}Config.cmake nor ${_NAME_LOWER}-config.cmake ${VERSION_MSG}")
endif()
endif()
endmacro()
function(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FIRST_ARG)
# set up the arguments for CMAKE_PARSE_ARGUMENTS and check whether we are in
# new extended or in the "old" mode:
set(options CONFIG_MODE HANDLE_COMPONENTS)
set(oneValueArgs FAIL_MESSAGE VERSION_VAR FOUND_VAR)
set(multiValueArgs REQUIRED_VARS)
set(_KEYWORDS_FOR_EXTENDED_MODE ${options} ${oneValueArgs} ${multiValueArgs} )
list(FIND _KEYWORDS_FOR_EXTENDED_MODE "${_FIRST_ARG}" INDEX)
if(${INDEX} EQUAL -1)
set(FPHSA_FAIL_MESSAGE ${_FIRST_ARG})
set(FPHSA_REQUIRED_VARS ${ARGN})
set(FPHSA_VERSION_VAR)
else()
CMAKE_PARSE_ARGUMENTS(FPHSA "${options}" "${oneValueArgs}" "${multiValueArgs}" ${_FIRST_ARG} ${ARGN})
if(FPHSA_UNPARSED_ARGUMENTS)
message(FATAL_ERROR "Unknown keywords given to FIND_PACKAGE_HANDLE_STANDARD_ARGS(): \"${FPHSA_UNPARSED_ARGUMENTS}\"")
endif()
if(NOT FPHSA_FAIL_MESSAGE)
set(FPHSA_FAIL_MESSAGE "DEFAULT_MSG")
endif()
endif()
# now that we collected all arguments, process them
if("x${FPHSA_FAIL_MESSAGE}" STREQUAL "xDEFAULT_MSG")
set(FPHSA_FAIL_MESSAGE "Could NOT find ${_NAME}")
endif()
# In config-mode, we rely on the variable <package>_CONFIG, which is set by find_package()
# when it successfully found the config-file, including version checking:
if(FPHSA_CONFIG_MODE)
list(INSERT FPHSA_REQUIRED_VARS 0 ${_NAME}_CONFIG)
list(REMOVE_DUPLICATES FPHSA_REQUIRED_VARS)
set(FPHSA_VERSION_VAR ${_NAME}_VERSION)
endif()
if(NOT FPHSA_REQUIRED_VARS)
message(FATAL_ERROR "No REQUIRED_VARS specified for FIND_PACKAGE_HANDLE_STANDARD_ARGS()")
endif()
list(GET FPHSA_REQUIRED_VARS 0 _FIRST_REQUIRED_VAR)
string(TOUPPER ${_NAME} _NAME_UPPER)
string(TOLOWER ${_NAME} _NAME_LOWER)
if(FPHSA_FOUND_VAR)
if(FPHSA_FOUND_VAR MATCHES "^${_NAME}_FOUND$" OR FPHSA_FOUND_VAR MATCHES "^${_NAME_UPPER}_FOUND$")
set(_FOUND_VAR ${FPHSA_FOUND_VAR})
else()
message(FATAL_ERROR "The argument for FOUND_VAR is \"${FPHSA_FOUND_VAR}\", but only \"${_NAME}_FOUND\" and \"${_NAME_UPPER}_FOUND\" are valid names.")
endif()
else()
set(_FOUND_VAR ${_NAME_UPPER}_FOUND)
endif()
# collect all variables which were not found, so they can be printed, so the
# user knows better what went wrong (#6375)
set(MISSING_VARS "")
set(DETAILS "")
# check if all passed variables are valid
unset(${_FOUND_VAR})
foreach(_CURRENT_VAR ${FPHSA_REQUIRED_VARS})
if(NOT ${_CURRENT_VAR})
set(${_FOUND_VAR} FALSE)
set(MISSING_VARS "${MISSING_VARS} ${_CURRENT_VAR}")
else()
set(DETAILS "${DETAILS}[${${_CURRENT_VAR}}]")
endif()
endforeach()
if(NOT "${${_FOUND_VAR}}" STREQUAL "FALSE")
set(${_FOUND_VAR} TRUE)
endif()
# component handling
unset(FOUND_COMPONENTS_MSG)
unset(MISSING_COMPONENTS_MSG)
if(FPHSA_HANDLE_COMPONENTS)
foreach(comp ${${_NAME}_FIND_COMPONENTS})
if(${_NAME}_${comp}_FOUND)
if(NOT DEFINED FOUND_COMPONENTS_MSG)
set(FOUND_COMPONENTS_MSG "found components: ")
endif()
set(FOUND_COMPONENTS_MSG "${FOUND_COMPONENTS_MSG} ${comp}")
else()
if(NOT DEFINED MISSING_COMPONENTS_MSG)
set(MISSING_COMPONENTS_MSG "missing components: ")
endif()
set(MISSING_COMPONENTS_MSG "${MISSING_COMPONENTS_MSG} ${comp}")
if(${_NAME}_FIND_REQUIRED_${comp})
set(${_FOUND_VAR} FALSE)
set(MISSING_VARS "${MISSING_VARS} ${comp}")
endif()
endif()
endforeach()
set(COMPONENT_MSG "${FOUND_COMPONENTS_MSG} ${MISSING_COMPONENTS_MSG}")
set(DETAILS "${DETAILS}[c${COMPONENT_MSG}]")
endif()
# version handling:
set(VERSION_MSG "")
set(VERSION_OK TRUE)
set(VERSION ${${FPHSA_VERSION_VAR}})
# check with DEFINED here as the requested or found version may be "0"
if (DEFINED ${_NAME}_FIND_VERSION)
if(DEFINED ${FPHSA_VERSION_VAR})
if(${_NAME}_FIND_VERSION_EXACT) # exact version required
# count the dots in the version string
string(REGEX REPLACE "[^.]" "" _VERSION_DOTS "${VERSION}")
# add one dot because there is one dot more than there are components
string(LENGTH "${_VERSION_DOTS}." _VERSION_DOTS)
if (_VERSION_DOTS GREATER ${_NAME}_FIND_VERSION_COUNT)
# Because of the C++ implementation of find_package() ${_NAME}_FIND_VERSION_COUNT
# is at most 4 here. Therefore a simple lookup table is used.
if (${_NAME}_FIND_VERSION_COUNT EQUAL 1)
set(_VERSION_REGEX "[^.]*")
elseif (${_NAME}_FIND_VERSION_COUNT EQUAL 2)
set(_VERSION_REGEX "[^.]*\\.[^.]*")
elseif (${_NAME}_FIND_VERSION_COUNT EQUAL 3)
set(_VERSION_REGEX "[^.]*\\.[^.]*\\.[^.]*")
else ()
set(_VERSION_REGEX "[^.]*\\.[^.]*\\.[^.]*\\.[^.]*")
endif ()
string(REGEX REPLACE "^(${_VERSION_REGEX})\\..*" "\\1" _VERSION_HEAD "${VERSION}")
unset(_VERSION_REGEX)
if (NOT ${_NAME}_FIND_VERSION VERSION_EQUAL _VERSION_HEAD)
set(VERSION_MSG "Found unsuitable version \"${VERSION}\", but required is exact version \"${${_NAME}_FIND_VERSION}\"")
set(VERSION_OK FALSE)
else ()
set(VERSION_MSG "(found suitable exact version \"${VERSION}\")")
endif ()
unset(_VERSION_HEAD)
else ()
if (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
set(VERSION_MSG "Found unsuitable version \"${VERSION}\", but required is exact version \"${${_NAME}_FIND_VERSION}\"")
set(VERSION_OK FALSE)
else ()
set(VERSION_MSG "(found suitable exact version \"${VERSION}\")")
endif ()
endif ()
unset(_VERSION_DOTS)
else() # minimum version specified:
if ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
set(VERSION_MSG "Found unsuitable version \"${VERSION}\", but required is at least \"${${_NAME}_FIND_VERSION}\"")
set(VERSION_OK FALSE)
else ()
set(VERSION_MSG "(found suitable version \"${VERSION}\", minimum required is \"${${_NAME}_FIND_VERSION}\")")
endif ()
endif()
else()
# if the package was not found, but a version was given, add that to the output:
if(${_NAME}_FIND_VERSION_EXACT)
set(VERSION_MSG "(Required is exact version \"${${_NAME}_FIND_VERSION}\")")
else()
set(VERSION_MSG "(Required is at least version \"${${_NAME}_FIND_VERSION}\")")
endif()
endif()
else ()
if(VERSION)
set(VERSION_MSG "(found version \"${VERSION}\")")
endif()
endif ()
if(VERSION_OK)
set(DETAILS "${DETAILS}[v${VERSION}(${${_NAME}_FIND_VERSION})]")
else()
set(${_FOUND_VAR} FALSE)
endif()
# print the result:
if (${_FOUND_VAR})
FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_FIRST_REQUIRED_VAR}} ${VERSION_MSG} ${COMPONENT_MSG}" "${DETAILS}")
else ()
if(FPHSA_CONFIG_MODE)
_FPHSA_HANDLE_FAILURE_CONFIG_MODE()
else()
if(NOT VERSION_OK)
_FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_FIRST_REQUIRED_VAR}})")
else()
_FPHSA_FAILURE_MESSAGE("${FPHSA_FAIL_MESSAGE} (missing: ${MISSING_VARS}) ${VERSION_MSG}")
endif()
endif()
endif ()
set(${_FOUND_VAR} ${${_FOUND_VAR}} PARENT_SCOPE)
endfunction()