Building client channels out of tree does not work reliable as the
dependencies can not be easily split. (exceptions may be simple ones
as echo channel)
It does complicate the build system and code though, so remove this
for maintainability reasons.
* Split out proxy headers and moved to public API to allow external
modules to be built.
* Split proxy into proxy library and proxy binary. The library
can be used by other applications and provides a simple API
* Improved channel passthrough, now all channels including dynamic
channels work.
* Extended module API to hook more events, improved module samples
* Cleaned up proxy code, removed global static variables used,
added WINPR_ASSERT
- fixed invalid, missing or additional arguments
- removed all type casts from arguments
- added missing (void*) typecasts for %p arguments
- use inttypes defines where appropriate
As building with -Wl,--no-undefined might cause issues when
combined with other linker flags (e.g. with -fsanitize=address see #3289)
it is now disabled per default but can be re-enabled with
-DWITH_NO_UNDEFINED=ON.
It is enabled for ci builds on linux to find undefined symbols.
