net/SocketDescriptor: specialization of FileDescriptor for network sockets

1 files changed, 205 insertions, 0 deletions

diff --git a/src/net/SocketDescriptor.hxx b/src/net/SocketDescriptor.hxx
new file mode 100644
index 000000000..96d7cdc35
--- /dev/null
+++ b/src/net/SocketDescriptor.hxx
@@ -0,0 +1,205 @@
+/*
+ * 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 SOCKET_DESCRIPTOR_HXX
+#define SOCKET_DESCRIPTOR_HXX
+
+#include "system/FileDescriptor.hxx"
+
+#include <type_traits>
+
+class SocketAddress;
+class StaticSocketAddress;
+
+/**
+ * An OO wrapper for a UNIX socket descriptor.
+ */
+class SocketDescriptor : protected FileDescriptor {
+protected:
+	explicit constexpr SocketDescriptor(int _fd)
+		:FileDescriptor(_fd) {}
+
+	explicit constexpr SocketDescriptor(FileDescriptor _fd)
+		:FileDescriptor(_fd) {}
+
+public:
+	SocketDescriptor() = default;
+
+	constexpr bool operator==(SocketDescriptor other) const {
+		return fd == other.fd;
+	}
+
+#ifndef _WIN32
+	/**
+	 * Convert a #FileDescriptor to a #SocketDescriptor.  This is only
+	 * possible on operating systems where socket descriptors are the
+	 * same as file descriptors (i.e. not on Windows).  Use this only
+	 * when you know what you're doing.
+	 */
+	static constexpr SocketDescriptor FromFileDescriptor(FileDescriptor fd) {
+		return SocketDescriptor(fd);
+	}
+
+	/**
+	 * Convert this object to a #FileDescriptor instance.  This is only
+	 * possible on operating systems where socket descriptors are the
+	 * same as file descriptors (i.e. not on Windows).  Use this only
+	 * when you know what you're doing.
+	 */
+	constexpr const FileDescriptor &ToFileDescriptor() const {
+		return *this;
+	}
+#endif
+
+	using FileDescriptor::IsDefined;
+	using FileDescriptor::IsValid;
+	using FileDescriptor::Get;
+	using FileDescriptor::Set;
+	using FileDescriptor::Steal;
+	using FileDescriptor::SetUndefined;
+
+	static constexpr SocketDescriptor Undefined() {
+		return SocketDescriptor(FileDescriptor::Undefined());
+	}
+
+#ifndef _WIN32
+	using FileDescriptor::SetNonBlocking;
+	using FileDescriptor::SetBlocking;
+	using FileDescriptor::EnableCloseOnExec;
+	using FileDescriptor::DisableCloseOnExec;
+	using FileDescriptor::Duplicate;
+	using FileDescriptor::Close;
+#else
+	/**
+	 * This method replaces FileDescriptor::Close(), using closesocket()
+	 * on Windows.  FileDescriptor::Close() is not virtual, so be
+	 * careful when dealing with a FileDescriptor reference that is
+	 * really a SocketDescriptor.
+	 */
+	void Close();
+#endif
+
+	/**
+	 * Create a socket.
+	 *
+	 * @param domain is the address domain
+	 * @param type is the sochet type
+	 * @param protocol is the protocol
+	 * @return True on success, False on failure
+	 * See man 2 socket for detailed information
+	 */
+	bool Create(int domain, int type, int protocol);
+
+	/**
+	 * Like Create(), but enable non-blocking mode.
+	 */
+	bool CreateNonBlock(int domain, int type, int protocol);
+
+	static bool CreateSocketPair(int domain, int type, int protocol,
+				     SocketDescriptor &a, SocketDescriptor &b);
+	static bool CreateSocketPairNonBlock(int domain, int type, int protocol,
+					     SocketDescriptor &a, SocketDescriptor &b);
+
+	int GetError();
+
+	bool SetOption(int level, int name, const void *value, size_t size);
+
+	bool SetBoolOption(int level, int name, bool _value) {
+		const int value = _value;
+		return SetOption(level, name, &value, sizeof(value));
+	}
+
+#ifdef __linux__
+	bool SetReuseAddress(bool value=true);
+	bool SetReusePort(bool value=true);
+	bool SetFreeBind(bool value=true);
+	bool SetNoDelay(bool value=true);
+	bool SetCork(bool value=true);
+
+	bool SetTcpDeferAccept(const int &seconds);
+	bool SetV6Only(bool value);
+
+	/**
+	 * Setter for SO_BINDTODEVICE.
+	 */
+	bool SetBindToDevice(const char *name);
+
+	bool SetTcpFastOpen(int qlen=16);
+#endif
+
+	bool Bind(SocketAddress address);
+
+#ifdef __linux__
+	/**
+	 * Binds the socket to a unique abstract address.
+	 */
+	bool AutoBind();
+#endif
+
+	bool Listen(int backlog);
+
+	SocketDescriptor Accept();
+	SocketDescriptor AcceptNonBlock(StaticSocketAddress &address) const;
+
+	bool Connect(SocketAddress address);
+
+	gcc_pure
+	StaticSocketAddress GetLocalAddress() const;
+
+	gcc_pure
+	StaticSocketAddress GetPeerAddress() const;
+
+	ssize_t Read(void *buffer, size_t length);
+	ssize_t Write(const void *buffer, size_t length);
+
+#ifdef _WIN32
+	int WaitReadable(int timeout_ms) const;
+	int WaitWritable(int timeout_ms) const;
+#else
+	using FileDescriptor::WaitReadable;
+	using FileDescriptor::WaitWritable;
+	using FileDescriptor::IsReadyForWriting;
+#endif
+
+	/**
+	 * Receive a datagram and return the source address.
+	 */
+	ssize_t Read(void *buffer, size_t length,
+		     StaticSocketAddress &address);
+
+	/**
+	 * Send a datagram to the specified address.
+	 */
+	ssize_t Write(const void *buffer, size_t length,
+		      SocketAddress address);
+};
+
+static_assert(std::is_trivial<SocketDescriptor>::value, "type is not trivial");
+
+#endif