This is a c-api wrapper over the hyperlight-guest crate. The purpose of this crate is to allow the creation of guests in the c language. This crate generates a .lib/.a library file depending on the platform, as well necessary header files.
For examples on how to use it, see the c simpleguest.
All guest functions must return a hl_Vec* obtained by calling one of the hl_flatbuffer_result_from_* functions. These functions will return a flatbuffer encoded byte-buffer of given value, for example hl_flatbuffer_result_from_int(int) will return the flatbuffer representation of the given int.
You may not construct and return your own hl_Vec*, as the hyperlight api assumes that all returned hl_Vec* are constructed through calls to a hl_flatbuffer_result_from_* function.
Additionally, note that type hl_Vec* is used in two different contexts. First, hl_Vec* is used input-parameter-type for guest functions that take a buffer of bytes. This buffer of bytes can contain arbitrary bytes. Second, all guest functions return a hl_Vec* (it might be hidden away by c macros). These hl_Vec* are flatbuffer-encoded data, and are not arbitrary.