WIP: IANA language stuff

cmake/scripts/generate_iana_language_subtag_registry.cmake

@@ -0,0 +1,37 @@
+#!/usr/bin/cmake -DOUTPUT_PATH=iana_language_subtag_registry.cpp -P
+# generates C++ code for the language-subtag-registry from www.iana.org, see https://tools.ietf.org/html/bcp47 and https://tools.ietf.org/html/rfc5646
+cmake_minimum_required(VERSION 3.3.0 FATAL_ERROR)
+
+if (NOT LANGUAGE_FILE)
+    set(LANGUAGE_FILE "language-subtag-registry.txt")
+endif ()
+if (EXISTS "${LANGUAGE_FILE}")
+    message(STATUS "Using existing language-subtag-registry file \"${LANGUAGE_FILE}\"")
+else()
+    message(STATUS "Downloading language-subtag-registry file from www.iana.org")
+    file(DOWNLOAD "https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry" "${LANGUAGE_FILE}")
+endif()
+if (NOT OUTPUT_PATH)
+    message(FATAL_ERROR "No OUTPUT_PATH specified.")
+endif()
+
+file(STRINGS "${LANGUAGE_FILE}" LANGUAGE_LIST)
+set(CURRENT_TYPE "")
+foreach (LINE ${LANGUAGE_LIST})
+    if (NOT CURRENT_TYPE)
+        if (LINE MATCHES "Type: (.*)")
+            set(CURRENT_TYPE "${CMAKE_MATCH_1}")
+        endif ()
+    else ()
+        if (LINE STREQUAL "%%")
+            unset(CURRENT_TYPE)
+            continue()
+        endif ()
+        if (CURRENT_TYPE STREQUAL "language")
+            if (LINE MATCHES "Description: (.*)")
+                message(STATUS "${CMAKE_MATCH_1}")
+            endif ()
+        endif ()
+    endif ()
+    #message(STATUS "Processing line: ${LINE}")
+endforeach()