Socket: Mark interface noexcept where applicable

Move constructors should always be marked noexcept, otherwise the object
cannot be placed into most standard library containers (as they
generally use std::move_if_noexcept to enforce strong exception
guarantees), and if this is false, then the container will fallback to
attempting to copy construct the object. Naturally, this cannot occur
without compilation errors for objects that have their copy constructor
and copy-assignment operators deleted (like Socket).

While we're at it, we can make most of the socket interface noexcept,
given they just forward to the POSIX socket functions.

include/jbus/Socket.hpp

@@ -21,13 +21,13 @@ class IPAddress {
   uint32_t m_address = 0;
   bool m_valid = false;
 
-  void resolve(const std::string& address);
+  void resolve(const std::string& address) noexcept;
 
 public:
-  explicit IPAddress(const std::string& address) { resolve(address); }
+  explicit IPAddress(const std::string& address) noexcept { resolve(address); }
 
-  uint32_t toInteger() const;
-  explicit operator bool() const { return m_valid; }
+  uint32_t toInteger() const noexcept;
+  explicit operator bool() const noexcept { return m_valid; }
 };
 
 /** Server-oriented TCP socket class derived from SFML */
@@ -40,23 +40,23 @@ class Socket {
   SocketTp m_socket = -1;
   bool m_isBlocking;
 
-  bool openSocket();
-  void setRemoteSocket(int remSocket);
+  bool openSocket() noexcept;
+  void setRemoteSocket(int remSocket) noexcept;
 
 public:
   enum class EResult { OK, Error, Busy };
 
 #ifdef _WIN32
-  static EResult LastWSAError();
+  static EResult LastWSAError() noexcept;
 #endif
 
-  explicit Socket(bool blocking) : m_isBlocking(blocking) {}
-  ~Socket() { close(); }
+  explicit Socket(bool blocking) noexcept : m_isBlocking(blocking) {}
+  ~Socket() noexcept { close(); }
 
   Socket(const Socket& other) = delete;
   Socket& operator=(const Socket& other) = delete;
-  Socket(Socket&& other) : m_socket(other.m_socket), m_isBlocking(other.m_isBlocking) { other.m_socket = -1; }
-  Socket& operator=(Socket&& other) {
+  Socket(Socket&& other) noexcept : m_socket(other.m_socket), m_isBlocking(other.m_isBlocking) { other.m_socket = -1; }
+  Socket& operator=(Socket&& other) noexcept {
     close();
     m_socket = other.m_socket;
     other.m_socket = -1;
@@ -64,21 +64,21 @@ public:
     return *this;
   }
 
-  void setBlocking(bool blocking);
-  bool isOpen() const { return m_socket != -1; }
-  bool openAndListen(const IPAddress& address, uint32_t port);
-  EResult accept(Socket& remoteSocketOut, sockaddr_in& fromAddress);
-  EResult accept(Socket& remoteSocketOut);
+  void setBlocking(bool blocking) noexcept;
+  bool isOpen() const noexcept { return m_socket != -1; }
+  bool openAndListen(const IPAddress& address, uint32_t port) noexcept;
+  EResult accept(Socket& remoteSocketOut, sockaddr_in& fromAddress) noexcept;
+  EResult accept(Socket& remoteSocketOut) noexcept;
   EResult accept(Socket& remoteSocketOut, std::string& fromHostname);
-  void close();
-  EResult send(const void* buf, size_t len, size_t& transferred);
-  EResult send(const void* buf, size_t len);
-  EResult recv(void* buf, size_t len, size_t& transferred);
-  EResult recv(void* buf, size_t len);
+  void close() noexcept;
+  EResult send(const void* buf, size_t len, size_t& transferred) noexcept;
+  EResult send(const void* buf, size_t len) noexcept;
+  EResult recv(void* buf, size_t len, size_t& transferred) noexcept;
+  EResult recv(void* buf, size_t len) noexcept;
 
-  explicit operator bool() const { return isOpen(); }
+  explicit operator bool() const noexcept { return isOpen(); }
 
-  SocketTp GetInternalSocket() const { return m_socket; }
+  SocketTp GetInternalSocket() const noexcept { return m_socket; }
 };
 
 } // namespace jbus::net