introduce some required cmake scripts

cmake/3rdPartyTargets.cmake

@@ -0,0 +1,51 @@
+# Author:
+#   Sven Czarnian <devel@svcz.de>
+# License:
+#   GPLv3
+# Brief:
+#   Creates the 3rd-party import targets
+
+# include the external project library
+INCLUDE(ExternalProject)
+
+# define the import target of libsodium
+ADD_LIBRARY(libsodium STATIC IMPORTED)
+IF (MSVC)
+    SET_TARGET_PROPERTIES(libsodium PROPERTIES
+        IMPORTED_IMPLIB_DEBUG "${CMAKE_SOURCE_DIR}/external/lib/libsodiumd.lib"
+        IMPORTED_IMPLIB_RELEASE "${CMAKE_SOURCE_DIR}/external/lib/libsodium.lib"
+    )
+    TARGET_INCLUDE_DIRECTORIES(libsodium INTERFACE "${CMAKE_SOURCE_DIR}/external/include")
+ELSE ()
+    MESSAGE(FATAL_ERROR "Unsupported compiler")
+ENDIF ()
+
+# define the import target of libzmq
+ADD_LIBRARY(libzmq STATIC IMPORTED)
+ADD_DEPENDENCIES(libzmq libsodium)
+IF (MSVC)
+    SET_TARGET_PROPERTIES(libzmq PROPERTIES
+        IMPORTED_IMPLIB_DEBUG "${CMAKE_SOURCE_DIR}/external/lib/libzmqd.lib"
+        IMPORTED_IMPLIB_RELEASE "${CMAKE_SOURCE_DIR}/external/lib/libzmq.lib"
+    )
+    TARGET_INCLUDE_DIRECTORIES(libzmq INTERFACE "${CMAKE_SOURCE_DIR}/external/include")
+ELSE ()
+    MESSAGE(FATAL_ERROR "Unsupported compiler")
+ENDIF ()
+
+# define the import target of cppzmq
+ADD_LIBRARY(cppzmq INTERFACE)
+TARGET_INCLUDE_DIRECTORIES(cppzmq INTERFACE "${CMAKE_SOURCE_DIR}/external/include")
+ADD_DEPENDENCIES(cppzmq libzmq)
+
+# define the import target of protobuf
+ADD_LIBRARY(protobuf STATIC IMPORTED)
+IF (MSVC)
+    SET_TARGET_PROPERTIES(protobuf PROPERTIES
+        IMPORTED_LOCATION_DEBUG "${CMAKE_INSTALL_PREFIX}/lib/libprotobufd.lib"
+        IMPORTED_LOCATION_RELEASE "${CMAKE_INSTALL_PREFIX}/lib/libprotobuf.lib"
+    )
+    TARGET_INCLUDE_DIRECTORIES(protobuf INTERFACE "${CMAKE_INSTALL_PREFIX}/include")
+ELSE ()
+    MESSAGE(FATAL_ERROR "Unsupported compiler")
+ENDIF ()