net/SocketDescriptor: specialization of FileDescriptor for network sockets

src/net/UniqueSocketDescriptor.hxx

@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2012-2017 Max Kellermann <max.kellermann@gmail.com>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
+ * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef UNIQUE_SOCKET_DESCRIPTOR_SOCKET_HXX
+#define UNIQUE_SOCKET_DESCRIPTOR_SOCKET_HXX
+
+#include "SocketDescriptor.hxx"
+
+#include <algorithm>
+#include <utility>
+
+class StaticSocketAddress;
+
+/**
+ * Wrapper for a socket file descriptor.
+ */
+class UniqueSocketDescriptor : public SocketDescriptor {
+public:
+	UniqueSocketDescriptor()
+		:SocketDescriptor(SocketDescriptor::Undefined()) {}
+
+	explicit UniqueSocketDescriptor(SocketDescriptor _fd)
+		:SocketDescriptor(_fd) {}
+	explicit UniqueSocketDescriptor(FileDescriptor _fd)
+		:SocketDescriptor(_fd) {}
+	explicit UniqueSocketDescriptor(int _fd):SocketDescriptor(_fd) {}
+
+	UniqueSocketDescriptor(UniqueSocketDescriptor &&other)
+		:SocketDescriptor(std::exchange(other.fd, -1)) {}
+
+	~UniqueSocketDescriptor() {
+		if (IsDefined())
+			Close();
+	}
+
+	/**
+	 * Release ownership and return the descriptor as an unmanaged
+	 * #SocketDescriptor instance.
+	 */
+	SocketDescriptor Release() {
+		return std::exchange(*(SocketDescriptor *)this, Undefined());
+	}
+
+	UniqueSocketDescriptor &operator=(UniqueSocketDescriptor &&src) {
+		std::swap(fd, src.fd);
+		return *this;
+	}
+
+	bool operator==(const UniqueSocketDescriptor &other) const {
+		return fd == other.fd;
+	}
+
+	/**
+	 * @return an "undefined" instance on error
+	 */
+	UniqueSocketDescriptor AcceptNonBlock(StaticSocketAddress &address) const {
+		return UniqueSocketDescriptor(SocketDescriptor::AcceptNonBlock(address));
+	}
+
+	static bool CreateSocketPair(int domain, int type, int protocol,
+				     UniqueSocketDescriptor &a,
+				     UniqueSocketDescriptor &b) {
+		return SocketDescriptor::CreateSocketPair(domain, type,
+							  protocol,
+							  a, b);
+	}
+
+	static bool CreateSocketPairNonBlock(int domain, int type, int protocol,
+					     UniqueSocketDescriptor &a,
+					     UniqueSocketDescriptor &b) {
+		return SocketDescriptor::CreateSocketPairNonBlock(domain, type,
+								  protocol,
+								  a, b);
+	}
+};
+
+#endif