This commit adds an MPS-specific compile-time option
`MBEDTLS_MPS_TRACE` to the internal MPS header `mps/common.h`.
So far -- this may need revisiting -- MPS comes with its own
internal tracing module which allows to track the operation of
MPS' various layers for the purpose of understanding of it workings
as well as for debugging.
The reasons for the introduction of a module separate from SSL debug
are the following:
1) The SSL debug module requires an SSL context to function because
debug callbacks are part of the runtime configuration of the SSL
module.
The MPS tracing module, in contrast, is not supposed to be used
in production environments, and there is no need for a runtime
configuration. Instead, a compile-time defined tracing callback
is used.
2) In the interest of modularity, MPS' tracing module shouldn't
require having an SSL context around.
3) Purely visually, MPS' tracing module adds support for indentation
according to call-depth and coloring according to which module is
being used, which makes it very useful for what's going on; however,
those features aren't available in the SSL debug module (and they
shouldn't be).
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
1ae9f756ba