Cases where C wrappers are needed

[david-bouyssie]

The goal of the issue is to list cases where SN might have troubles to bind some C definitions, and where C wrappers are required as workarounds.

List of possible issues:

• variadic functions and functions accepting a va_list argument
• global constants
• global variables

Regarding globals several issues can be considered:

• globals are not always exported, this is particularly the case on Windows, depending on the compiler (and compiler configuration) which was used to generate the DLL
• a non-constant global will be defined in the Scala Native extern val with its initial value only
• SN doesn't support passing structs by value
• char[] vs char*: SN can currently deal with constant strings defined as char* but not with char[]

Workarounds:

• for each global variable, create a C getter, this should allow to bypass the different mentioned issues
• convert char[] into char*
• return global structs using a pointer provided to the C getter