Strings and Buffers

For an improved experience when working with strings, UCX provides an API to work with structures that store a string together with its length, as well as a more sophisticated buffer API for working with text of dynamic or unknown length.

Additionally, UCX offers several advanced printf-like functions that also allow the convenient work with strings of unknown length. For example, one the more advanced functions is cx_sprintf_sa() which lets you format a string into an existing pre-allocated buffer (e.g. on the stack) and automatically switches to a fresh buffer allocated by a custom allocator when the existing buffer is not large enough.

The string API is designed to work with both mutable and constant strings. The possibility to work with constant strings is especially important, when you want to work with string literals without copying them into a separate memory region - e.g. when you want to obtain a substring.

By default, UCX assumes strings are constant and stores them in a structure of type cxstring. Mutable strings are stored in a separate structure called cxmutstr. You can conveniently convert any UCX string to a cxstring by using cx_strcast(). Several macros throughout UCX already do that for you. Since this function is usually inlined, this comes with no additional cost when compiled with optimizations enabled.