Merge bitcoin/bitcoin#25428: Remove Sock::Release() and CloseSocket()

a724c39606 net: rename Sock::Reset() to Sock::Close() and make it private (Vasil Dimov)
e8ff3f0c52 net: remove CloseSocket() (Vasil Dimov)
175fb2670a net: remove now unused Sock::Release() (Vasil Dimov)

Pull request description:

  _This is a piece of #21878, chopped off to ease review._

  * `Sock::Release()` is unused, thus remove it
  * `CloseSocket()` is only called from `Sock::Reset()`, so move the body of `CloseSocket()` inside `Sock::Reset()` and remove `CloseSocket()` - this helps to hide low level file descriptor sockets inside the `Sock` class.
  * Rename `Sock::Reset()` to `Sock::Close()` and make it `private` - to be used only in the destructor and in the `Sock` assignment operator. This simplifies the public API by removing one method from it.

ACKs for top commit:
  laanwj:
    Code review ACK a724c39606

Tree-SHA512: 4b12586642b3d049092fadcb1877132e285ec66a80af92563a7703c6970e278e0f2064fba45c7eaa78eb65db94b3641fd5e5264f7b4f61116d1a6f3333868639

src/test/fuzz/util.cpp

@@ -24,10 +24,10 @@ FuzzedSock::FuzzedSock(FuzzedDataProvider& fuzzed_data_provider)
 FuzzedSock::~FuzzedSock()
 {
     // Sock::~Sock() will be called after FuzzedSock::~FuzzedSock() and it will call
-    // Sock::Reset() (not FuzzedSock::Reset()!) which will call CloseSocket(m_socket).
+    // close(m_socket) if m_socket is not INVALID_SOCKET.
     // Avoid closing an arbitrary file descriptor (m_socket is just a random very high number which
     // theoretically may concide with a real opened file descriptor).
-    Reset();
+    m_socket = INVALID_SOCKET;
 }
 
 FuzzedSock& FuzzedSock::operator=(Sock&& other)
@@ -36,11 +36,6 @@ FuzzedSock& FuzzedSock::operator=(Sock&& other)
     return *this;
 }
 
-void FuzzedSock::Reset()
-{
-    m_socket = INVALID_SOCKET;
-}
-
 ssize_t FuzzedSock::Send(const void* data, size_t len, int flags) const
 {
     constexpr std::array send_errnos{

src/test/fuzz/util.h

@@ -55,8 +55,6 @@ public:
 
     FuzzedSock& operator=(Sock&& other) override;
 
-    void Reset() override;
-
     ssize_t Send(const void* data, size_t len, int flags) const override;
 
     ssize_t Recv(void* buf, size_t len, int flags) const override;

src/test/sock_tests.cpp

@@ -69,24 +69,6 @@ BOOST_AUTO_TEST_CASE(move_assignment)
     BOOST_CHECK(SocketIsClosed(s));
 }
 
-BOOST_AUTO_TEST_CASE(release)
-{
-    SOCKET s = CreateSocket();
-    Sock* sock = new Sock(s);
-    BOOST_CHECK_EQUAL(sock->Release(), s);
-    delete sock;
-    BOOST_CHECK(!SocketIsClosed(s));
-    BOOST_REQUIRE(CloseSocket(s));
-}
-
-BOOST_AUTO_TEST_CASE(reset)
-{
-    const SOCKET s = CreateSocket();
-    Sock sock(s);
-    sock.Reset();
-    BOOST_CHECK(SocketIsClosed(s));
-}
-
 #ifndef WIN32 // Windows does not have socketpair(2).
 
 static void CreateSocketPair(int s[2])

src/test/util/net.h

@@ -100,7 +100,7 @@ public:
         m_socket = INVALID_SOCKET - 1;
     }
 
-    ~StaticContentsSock() override { Reset(); }
+    ~StaticContentsSock() override { m_socket = INVALID_SOCKET; }
 
     StaticContentsSock& operator=(Sock&& other) override
     {
@@ -108,11 +108,6 @@ public:
         return *this;
     }
 
-    void Reset() override
-    {
-        m_socket = INVALID_SOCKET;
-    }
-
     ssize_t Send(const void*, size_t len, int) const override { return len; }
 
     ssize_t Recv(void* buf, size_t len, int flags) const override