In commit eac1bec428 we start to use the
ringbuffer inside the console printing code. As a result, we must not
use TRACE_*() or printf() from within ringbuffer.c code to avoid
infinite recursion.
Instead, let rbuf_write() return a negative return value in case the
ring buffer overflows. This way, the callers (outside the
console/stdout code) can print an error message themselves.
Change-Id: Ib009f013be119dbad22fa2b7d60ec8dee59baee5
This way we can easily check with 'diff' for differences in our code and
Atmel softpack. Also, this layout is more suitable for building various
different firmware images (e.g. factory-test, dfu-loader, main
application) for a variety of different boards (simtrace, owhw, qmod).