Establish a new distributed CMake architecture with CMake code related to
a source directory moving to be in the subdir in its own CMakeLists.txt.
In particular, there's now one in ./lib which calls through to ones
further down the directory tree like ./lib/plat/xxx, ./lib/roles/xxx etc.
This cuts the main CMakelists.txt from 98KB -> 33KB, about a 66% reduction,
and it's much easier to maintain sub-CMakeLists.txt that are in the same
directory as the sources they manage, and conceal all the details that that
level.
Child CMakelists.txt become responsible for:
- include_directories() definition (this is not supported by CMake
directly, it passes it back up via PARENT_SCOPE vars in helper
macros)
- Addition child CMakeLists.txt inclusion, for example toplevel ->
role -> role subdir
- Source file addition to the build
- Dependent library path resolution... this is now a private thing
in the child CMakeLists.txt, it just passes back any adaptations
to include_directories() and the LIB_LIST without filling the
parent namespace with the details
Add support for external pthreads lib on windows and some docs about how to do.
It can build with LWS_WITH_THREADPOOL and LWS_WITH_MINIMAL_EXAMPLES including the
pthreads-dependent ones without warnings or errors on windows platform as well with this.
pthreads_t can be anything, including a struct - not a pointer-to-a-struct
but the struct itself. These can't be cast to a void * for printing as they can
on linux, where the base type is a pointer.
Let's fix all the usage of those to determine their own thread index in terms
of the meaning to the program rather than as a tid.
Fix pthreads detection in the minimal examples and add it where needed.
Fix unistd.h include to be conditional on not WIN32
With this, -DLWS_WITH_MINIMAL_EXAMPLES=1 is happy and warning-free
on windows.
In the case code is composed into a single process, but it isn't monolithic in the
sense it's made up of modular "applications" that are written separate projects,
provide a way for the "applications" to request a callback from the lws event loop
thread context safely.
From the callback the applications can set up their operations on the lws event
loop and drop their own thread.
Since it requires system-specific locking to be threadsafe, provide a non-threadsafe
helper and then indirect the actual usage through a user-defined lws_system ops
function pointer that wraps the unsafe api with the system locking to make it safe.
