cmake_host_system_information: Make it available for all systems

Before it was Linux only.

Help/command/cmake_host_system_information.rst

@@ -132,9 +132,6 @@ queried.  The list of queried values is stored in ``<variable>``.
 
   See :variable:`CMAKE_HOST_SYSTEM_PROCESSOR`
 
-For Linux distributions additional ``<key>`` values are available to get operating
-system identification as described in the `man 5 os-release`_.
-
 ``DISTRIB_INFO``
   .. versionadded:: 3.22
 
@@ -144,7 +141,8 @@ system identification as described in the `man 5 os-release`_.
 ``DISTRIB_<name>``
   .. versionadded:: 3.22
 
-  Get the ``<name>`` variable if it exists in the :file:`/etc/os-release` file
+  Get the ``<name>`` variable (see `man 5 os-release`_) if it exists in the
+  :file:`/etc/os-release` file
 
   Example:
 

Source/cmCMakeHostSystemInformationCommand.cxx

@@ -149,7 +149,6 @@ cm::optional<std::string> GetValue(cmsys::SystemInformation& info,
   return {};
 }
 
-#ifdef __linux__
 cm::optional<std::pair<std::string, std::string>> ParseOSReleaseLine(
   std::string const& line)
 {
@@ -407,7 +406,6 @@ cm::optional<std::string> GetValue(cmExecutionStatus& status,
   // NOTE Empty string means requested variable not set
   return std::string{};
 }
-#endif
 
 #ifdef HAVE_VS_SETUP_HELPER
 cm::optional<std::string> GetValue(cmExecutionStatus& status,
@@ -494,9 +492,7 @@ bool cmCMakeHostSystemInformationCommand(std::vector<std::string> const& args,
     auto value =
       GetValueChained(
           [&]() { return GetValue(info, key); }
-#ifdef __linux__
         , [&]() { return GetValue(status, key, variable); }
-#endif
 #ifdef HAVE_VS_SETUP_HELPER
         , [&]() { return GetValue(status, key); }
 #endif

Tests/RunCMake/CMakeLists.txt

@@ -349,7 +349,7 @@ if(NOT CMake_TEST_EXTERNAL_CMAKE)
 endif()
 add_RunCMake_test(execute_process)
 add_RunCMake_test(export)
-add_RunCMake_test(cmake_host_system_information -DCMAKE_SYSTEM_NAME=${CMAKE_SYSTEM_NAME})
+add_RunCMake_test(cmake_host_system_information)
 add_RunCMake_test(cmake_language)
 add_RunCMake_test(cmake_minimum_required)
 add_RunCMake_test(cmake_parse_arguments)

Tests/RunCMake/cmake_host_system_information/RunCMakeTest.cmake

@@ -7,15 +7,11 @@ run_cmake(BadArg3)
 run_cmake(QueryList)
 run_cmake(QueryKeys)
 
-if (CMAKE_SYSTEM_NAME MATCHES "Linux")
+run_cmake(UnitTest)
+run_cmake(Exherbo)
+run_cmake(Ubuntu)
 
-  run_cmake_with_options(UnitTest)
-  run_cmake_with_options(Exherbo)
-  run_cmake_with_options(Ubuntu)
+run_cmake(CentOS6)
+run_cmake(Debian6)
 
-  run_cmake_with_options(CentOS6)
-  run_cmake_with_options(Debian6)
-
-  run_cmake_with_options(UserFallbackScript)
-
-endif()
+run_cmake(UserFallbackScript)