Merge branch 'rightlib' into mergelibs-240408-0819

4 files changed, 214 insertions, 2 deletions

diff --git a/library/cpp/http/io/chunk.h b/library/cpp/http/io/chunk.h
index 88d89fafda2..6d477b04a9b 100644
--- a/library/cpp/http/io/chunk.h
+++ b/library/cpp/http/io/chunk.h
@@ -35,8 +35,10 @@ public:
     TChunkedOutput(IOutputStream* slave);
     ~TChunkedOutput() override;
 
-private:
+protected:
     void DoWrite(const void* buf, size_t len) override;
+
+private:
     void DoFlush() override;
     void DoFinish() override;
 
diff --git a/library/cpp/tld/tlds-alpha-by-domain.txt b/library/cpp/tld/tlds-alpha-by-domain.txt
index 374cf501922..eb3b65c176b 100644
--- a/library/cpp/tld/tlds-alpha-by-domain.txt
+++ b/library/cpp/tld/tlds-alpha-by-domain.txt
@@ -1,4 +1,4 @@
-# Version 2024033102, Last Updated Mon Apr  1 07:07:01 2024 UTC
+# Version 2024040700, Last Updated Sun Apr  7 07:07:01 2024 UTC
 AAA
 AARP
 ABB
diff --git a/library/cpp/yt/misc/function_view-inl.h b/library/cpp/yt/misc/function_view-inl.h
new file mode 100644
index 00000000000..ececfdf3357
--- /dev/null
+++ b/library/cpp/yt/misc/function_view-inl.h
@@ -0,0 +1,71 @@
+#pragma once
+#ifndef FUNCTION_VIEW_INL_H_
+#error "Direct inclusion of this file is not allowed, include function_view.h"
+// For the sake of sane code completion.
+#include "function_view.h"
+#endif
+
+#include <library/cpp/yt/assert/assert.h>
+
+namespace NYT {
+
+////////////////////////////////////////////////////////////////////////////////
+
+template <class TResult, bool NoExcept, class... TArgs>
+template <CTypeErasable<TResult(TArgs...) noexcept(NoExcept)> TConcrete>
+TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::TFunctionView(TConcrete& concreteRef) noexcept
+    : TFunctionView(&concreteRef)
+{ }
+
+template <class TResult, bool NoExcept, class... TArgs>
+template <CTypeErasable<TResult(TArgs...) noexcept(NoExcept)> TConcrete>
+TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::TFunctionView(TConcrete* concretePtr) noexcept
+{
+    Ptr_ = reinterpret_cast<void*>(concretePtr);
+    Invoke_ = &TFunctionView::ConcreteInvoke<TConcrete>;
+}
+
+template <class TResult, bool NoExcept, class... TArgs>
+TFunctionView<TResult(TArgs...) noexcept(NoExcept)>
+TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::Release() noexcept
+{
+    auto copy = *this;
+    Reset();
+    return copy;
+}
+
+template <class TResult, bool NoExcept, class... TArgs>
+TResult TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::operator()(TArgs... args) noexcept(NoExcept)
+{
+    YT_VERIFY(Ptr_);
+    return Invoke_(std::forward<TArgs>(args)..., Ptr_);
+}
+
+template <class TResult, bool NoExcept, class... TArgs>
+template <class TConcrete>
+TResult TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::ConcreteInvoke(TArgs... args, TErasedPtr ptr) noexcept(NoExcept)
+{
+    return (*reinterpret_cast<TConcrete*>(ptr))(std::forward<TArgs>(args)...);
+}
+
+template <class TResult, bool NoExcept, class... TArgs>
+TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::operator bool() const noexcept
+{
+    return IsValid();
+}
+
+template <class TResult, bool NoExcept, class... TArgs>
+bool TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::IsValid() const noexcept
+{
+    return Ptr_ != nullptr;
+}
+
+template <class TResult, bool NoExcept, class... TArgs>
+void TFunctionView<TResult(TArgs...) noexcept(NoExcept)>::Reset() noexcept
+{
+    Ptr_ = nullptr;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NYT
diff --git a/library/cpp/yt/misc/function_view.h b/library/cpp/yt/misc/function_view.h
new file mode 100644
index 00000000000..259238521ff
--- /dev/null
+++ b/library/cpp/yt/misc/function_view.h
@@ -0,0 +1,139 @@
+#pragma once
+
+#include <concepts>
+
+namespace NYT {
+
+////////////////////////////////////////////////////////////////////////////////
+
+namespace NDetail {
+
+template <class TSignature>
+struct TTypeErasureTraits;
+
+template <class TResult, bool NoExcept, class... TArgs>
+struct TTypeErasureTraits<TResult(TArgs...) noexcept(NoExcept)>
+{
+    using TSignature = TResult(TArgs...) noexcept(NoExcept);
+
+    // TODO(arkady-e1ppa): Support pointer-to-member-function?
+    template <class T>
+    static constexpr bool IsInvocable = NoExcept
+        ? requires (T obj, TArgs... args) {
+            { obj(std::forward<TArgs>(args)...) } noexcept -> std::same_as<TResult>;
+        }
+        : requires (T obj, TArgs... args) {
+            { obj(std::forward<TArgs>(args)...) } -> std::same_as<TResult>;
+        };
+};
+
+} // namespace NDetail
+
+////////////////////////////////////////////////////////////////////////////////
+
+// Non-owning type-erasure container.
+/*
+    Example:
+
+    template <class T>
+    class TSerializedObject
+    {
+    public:
+        explicit TSerializedObject(T value)
+            : Object_(value)
+        { }
+
+        void Lock(TFunctionView<void(const T&)> callback)
+        {
+            auto guard = Guard(SpinLock_);
+            callback(Object_);
+        }
+
+    private:
+        TSpinLock SpinLock_;
+        T Object_;
+    };
+
+    int main()
+    {
+        TSerializedObject<int> object(42);
+
+        // object.Lock([] (const int& value) {
+        //     fmt::println("Value is {}", value);
+        // });
+        // ^ CE -- cannot pass rvalue.
+
+        auto callback = [] (const int& value) {
+            fmt::println("Value is {}", value);
+        };
+
+        object.Lock(callback); // <- prints "Value is 42".
+    }
+*/
+template <class TSignature>
+class TFunctionView;
+
+////////////////////////////////////////////////////////////////////////////////
+
+template <class T, class TSignature>
+concept CTypeErasable =
+    NDetail::TTypeErasureTraits<TSignature>::template IsInvocable<T> &&
+    (!std::same_as<T, TFunctionView<TSignature>>);
+
+////////////////////////////////////////////////////////////////////////////////
+
+template <class TResult, bool NoExcept, class... TArgs>
+class TFunctionView<TResult(TArgs...) noexcept(NoExcept)>
+{
+public:
+    using TSignature = TResult(TArgs...) noexcept(NoExcept);
+
+    TFunctionView() = default;
+
+    template <CTypeErasable<TSignature> TConcrete>
+    TFunctionView(TConcrete& concreteRef) noexcept;
+
+    template <CTypeErasable<TSignature> TConcrete>
+    TFunctionView(TConcrete* concretePtr) noexcept;
+
+    TResult operator()(TArgs... args) noexcept(NoExcept);
+
+    explicit operator bool() const noexcept;
+
+    TFunctionView Release() noexcept;
+
+    bool IsValid() const noexcept;
+    void Reset() noexcept;
+
+    // bool operator==(const TFunctionView& other) const & = default;
+
+private:
+    // NB: Technically, this is UB according to C standard, which
+    // was not changed for C++ standard.
+    // This is so because it is allowed to have
+    // function pointers to be modelled by entities
+    // different from object pointers.
+    // No reasonable system architecture (e.g. x86 or ARM
+    // or any other POSIX compliant one) does this.
+    // No reasonable compiler (clang/gcc) does anything with this.
+    // Accounting for such requirement would cause this class
+    // to have std::variant-like storage which would make this class
+    // weight more. Thus, we have decided to keep it this way,
+    // since we are safe on x86 or ARM + clang.
+    using TErasedPtr = void*;
+    using TErasedInvoke = TResult(*)(TArgs..., TErasedPtr);
+
+    TErasedPtr Ptr_ = nullptr;
+    TErasedInvoke Invoke_ = nullptr;
+
+    template <class TConcrete>
+    static TResult ConcreteInvoke(TArgs... args, TErasedPtr ptr) noexcept(NoExcept);
+};
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NYT
+
+#define FUNCTION_VIEW_INL_H_
+#include "function_view-inl.h"
+#undef FUNCTION_VIEW_INL_H_