Last time I checked (that was many many years ago) CCS didn't have a linker. I don't know if that is still the case now but if it is, your library wouldn't mean much as the basic idea of a library is to put the code in a precompiled object state ready to be linked whenever needed without any further compilation of the library, saving time.
Or in case you are trying to collect your mostly used funtions into a 'header' (.h) file, that's not actually called a library. You can achieve this by putting your function declarations and definitions in the header file and then including this file in your 'main.c' by
#include insert_your_file_here.h
Then all your functions in the .h file should be available.