general: Use a submodule of eggert/tz

externals/CMakeLists.txt

@@ -0,0 +1 @@
+add_subdirectory(tz)

externals/tz/CMakeLists.txt

@@ -0,0 +1,34 @@
+set(TZ_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/tz")
+set(TZ_DIR "${CMAKE_CURRENT_BINARY_DIR}/tz")
+set(TZ_ZONEINFO_DIR "${TZ_DIR}/usr/share/zoneinfo" CACHE PATH "Time zone info data directory")
+set(TZIF_LIST_FILE "${CMAKE_CURRENT_BINARY_DIR}/tzif_list.txt" CACHE PATH "List of zone info files")
+
+find_program(GNU_MAKE make)
+if ("${GNU_MAKE}" STREQUAL "GNU_MAKE-NOTFOUND")
+    message(FATAL_ERROR "GNU make not found")
+endif()
+
+if (NOT EXISTS "${TZ_DIR}" OR NOT EXISTS "${TZIF_LIST_FILE}")
+    execute_process(
+        COMMAND
+            ${GNU_MAKE} DESTDIR=${TZ_DIR} install
+        WORKING_DIRECTORY 
+            ${TZ_SOURCE_DIR}
+        COMMAND_ERROR_IS_FATAL ANY
+    )
+
+    # Step taken by Arch Linux packaging, but Nintendo apparently skips it
+    # execute_process(
+    #     COMMAND
+    #         "${TZDB_LOCATION}/zic" -b fat -d ${TZDB_ZONEINFO} africa antarctica asia australasia europe northamerica southamerica etcetera backward factory
+    #     WORKING_DIRECTORY
+    #         "${TZDB_LOCATION}"
+    #     COMMAND_ERROR_IS_FATAL ANY
+    # )
+
+    execute_process(
+        COMMAND
+            /bin/bash "${CMAKE_CURRENT_SOURCE_DIR}/find_tzif.sh" "${TZ_ZONEINFO_DIR}" "${TZIF_LIST_FILE}"
+        COMMAND_ERROR_IS_FATAL ANY
+    )
+endif()

externals/tz/find_tzif.sh

@@ -0,0 +1,14 @@
+#/bin/bash
+set -e
+directory=$1
+tzif_list=$2
+
+truncate -s 0 $tzif_list
+
+for i in `find $directory -type f`; do
+    header=`head -c 4 $i`
+    if [ "$header" == "TZif" ]; then
+        echo "$i" >> $tzif_list
+    fi
+done
+