Add default empty files and a CMakeLists.txt to build.

CMakeLists.txt

@@ -0,0 +1,12 @@
+cmake_minimum_required(VERSION 2.7)
+project(libregex)
+
+add_library(regex STATIC src/libregex.c)
+add_executable(libregex src/main.c)
+add_subdirectory(external/libds)
+
+target_include_directories(regex PUBLIC include)
+target_include_directories(libregex PUBLIC include)
+
+target_link_libraries(regex ds)
+target_link_libraries(libregex regex)