YT-19210: expose YQL shared library for YT.

After this, a new target libyqlplugin.so appears. in open-source cmake build.
Diff in open-source YDB repo looks like the following: https://paste.yandex-team.ru/f302bdb4-7ef2-4362-91c7-6ca45f329264

1 files changed, 69 insertions, 0 deletions

diff --git a/library/cpp/threading/cron/cron.cpp b/library/cpp/threading/cron/cron.cpp
new file mode 100644
index 0000000000..e7c1c59735
--- /dev/null
+++ b/library/cpp/threading/cron/cron.cpp
@@ -0,0 +1,69 @@
+#include "cron.h"
+
+#include <library/cpp/deprecated/atomic/atomic.h>
+
+#include <util/system/thread.h>
+#include <util/system/event.h>
+
+using namespace NCron;
+
+namespace {
+    struct TPeriodicHandle: public IHandle {
+        inline TPeriodicHandle(TJob job, TDuration interval, const TString& threadName)
+            : Job(job)
+            , Interval(interval)
+            , Done(false)
+        {
+            TThread::TParams params(DoRun, this);
+            if (!threadName.empty()) {
+                params.SetName(threadName);
+            }
+            Thread = MakeHolder<TThread>(params);
+            Thread->Start();
+        }
+
+        static inline void* DoRun(void* data) noexcept {
+            ((TPeriodicHandle*)data)->Run();
+
+            return nullptr;
+        }
+
+        inline void Run() noexcept {
+            while (true) {
+                Job();
+
+                Event.WaitT(Interval);
+
+                if (AtomicGet(Done)) {
+                    return;
+                }
+            }
+        }
+
+        ~TPeriodicHandle() override {
+            AtomicSet(Done, true);
+            Event.Signal();
+            Thread->Join();
+        }
+
+        TJob Job;
+        TDuration Interval;
+        TManualEvent Event;
+        TAtomic Done;
+        THolder<TThread> Thread;
+    };
+}
+
+IHandlePtr NCron::StartPeriodicJob(TJob job) {
+    return NCron::StartPeriodicJob(job, TDuration::Seconds(0), "");
+}
+
+IHandlePtr NCron::StartPeriodicJob(TJob job, TDuration interval) {
+    return NCron::StartPeriodicJob(job, interval, "");
+}
+
+IHandlePtr NCron::StartPeriodicJob(TJob job, TDuration interval, const TString& threadName) {
+    return new TPeriodicHandle(job, interval, threadName);
+}
+
+IHandle::~IHandle() = default;