[Bug 41220] New: Provide fallback implementation of strnlen for OS versions that don' t have it in their Libc (Leopard, Snow Leopard, et al)

https://bugs.winehq.org/show_bug.cgi?id=41220

Bug ID: 41220
           Summary: Provide fallback implementation of strnlen for OS
                    versions that don't have it in their Libc (Leopard,
                    Snow Leopard, et al)
           Product: Wine
           Version: 1.9.17
          Hardware: x86
                OS: Mac OS X
            Status: UNCONFIRMED
          Severity: minor
          Priority: P2
         Component: directx-d3d
          Assignee: [e-mail]
          Reporter: [e-mail]

wine-1.9.17 is failing to build on Leopard and Snow Leopard due to strnlen not
being available on those OS versions, where d3d10.dll.so and d3d11.dll.so fail
to link with:

Undefined symbols for architecture i386:
  "_strnlen", referenced from:
      _fx10_get_string in effect.o

Undefined symbols for architecture i386:
  "_strnlen", referenced from:
      _shader_parse_signature in shader.o

A fallback implementation of strnlen should be provided for such cases.