64fb0ac Declare single-argument (non-converting) constructors "explicit" (practicalswift)
Pull request description:
Declare single-argument (non-converting) constructors `explicit`.
In order to avoid unintended implicit conversions.
For a more thorough discussion, see ["C.46: By default, declare single-argument constructors explicit"](http://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#c46-by-default-declare-single-argument-constructors-explicit) in the C++ Core Guidelines (Stroustrup & Sutter).
Tree-SHA512: e0c6922e56b11fa402621a38656d8b1122d16dd8f160e78626385373cf184ac7f26cb4c1851eca47e9b0dbd5e924e39a85c3cbdcb627a05ee3a655ecf5f7a0f1
a56f8b0 Add missing lock in CScheduler::AreThreadsServicingQueue() (Matt Corallo)
Pull request description:
Not an actual bug as this is only used in asserts right now, but
nice to not have a missing lock.
Tree-SHA512: 7e542b150a0be716783e196493d239f2ad15e5376abf54b67d735dc3ef1b10849c090337b849f530c9f7497ddcfb8389b47d64a5dcf6382b7d38838f88cc1100
1f668b6 Expose if CScheduler is being serviced, assert its not in EmptyQueue (Matt Corallo)
3192975 Flush CValidationInterface callbacks prior to destruction (Matt Corallo)
08096bb Support more than one CScheduler thread for serial clients (Matt Corallo)
2fbf2db Add default arg to CScheduler to schedule() a callback now (Matt Corallo)
cda1429 Give CMainSignals a reference to the global scheduler (Matt Corallo)
3a19fed Make ValidationInterface signals-type-agnostic (Matt Corallo)
ff6a834 Use TestingSetup to DRY qt rpcnestedtests (Matt Corallo)
Tree-SHA512: fab91e34e30b080ed4d0a6d8c1214910e383c45440676e37be61d0bde6ae98d61e8903d22b846e95ba4e73a6ce788798350266feba246d8a2ab357e8523e4ac5
888cce5 Add perf counter data to GetStrongRandBytes state in scheduler (Matt Corallo)
399fb8f Add internal method to add new random data to our internal RNG state (Matt Corallo)
Tree-SHA512: 9732a3804d015eaf48d56b60c73880014845fd17a098f1ac2eff6bd50a4beb8b8be65956ac1f0d641e96e3a53c17daddd919401edbf2e3797c3fb687730fb913
Don't clear `stopRequested` and `stopWhenEmpty` at the top of
`serviceQueue`, as this results in a race condition: on systems under
heavy load, some of the threads only get scheduled on the CPU when the
other threads have already finished their work. This causes the flags to
be cleared post-hoc and thus those threads to wait forever.
The potential drawback of this change is that the scheduler cannot be
restarted after being stopped (an explicit reset would be needed), but
we don't use this functionality anyway.
On a busy or slow system, the CScheduler unit test could fail because it
assumed all threads would be done after a couple of milliseconds.
Replace the hard-coded sleep with CScheduler stop() method that
will cleanly exit the servicing threads when all tasks are completely
finished.
