STRING

STRING provides a way to allocate and free text strings, while de-duplicating them.

It can be used similarly to libc string functions:

strdup() and strdupz() become string_strdupz().
strlen() becomes string_strlen() (and it does not walkthrough the bytes of the string).
free() and freez() become string_freez().

There is also a special string_dup() function that increases the reference counter of a STRING, avoiding the index lookup to find it.

Once there is a STRING *, the actual const char * can be accessed with string2str().

All STRING should be constant. Changing the contents of a const char * that has been acquired by string2str() should never happen.