1 files changed, 363 insertions, 0 deletions
diff --git a/src/network/socket.cpp b/src/network/socket.cpp
new file mode 100644
index 000000000..053013606
--- /dev/null
+++ b/src/network/socket.cpp
@@ -0,0 +1,363 @@
+/*
+Minetest
+Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "socket.h"
+
+#include <cstdio>
+#include <iostream>
+#include <cstdlib>
+#include <cstring>
+#include <cerrno>
+#include <sstream>
+#include <iomanip>
+#include "util/string.h"
+#include "util/numeric.h"
+#include "constants.h"
+#include "debug.h"
+#include "settings.h"
+#include "log.h"
+
+#ifdef _WIN32
+// Without this some of the network functions are not found on mingw
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT 0x0501
+#endif
+#include <windows.h>
+#include <winsock2.h>
+#include <ws2tcpip.h>
+#define LAST_SOCKET_ERR() WSAGetLastError()
+typedef SOCKET socket_t;
+typedef int socklen_t;
+#else
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#define LAST_SOCKET_ERR() (errno)
+typedef int socket_t;
+#endif
+
+// Set to true to enable verbose debug output
+bool socket_enable_debug_output = false; // yuck
+
+static bool g_sockets_initialized = false;
+
+// Initialize sockets
+void sockets_init()
+{
+#ifdef _WIN32
+	// Windows needs sockets to be initialized before use
+	WSADATA WsaData;
+	if (WSAStartup(MAKEWORD(2, 2), &WsaData) != NO_ERROR)
+		throw SocketException("WSAStartup failed");
+#endif
+	g_sockets_initialized = true;
+}
+
+void sockets_cleanup()
+{
+#ifdef _WIN32
+	// On Windows, cleanup sockets after use
+	WSACleanup();
+#endif
+}
+
+/*
+	UDPSocket
+*/
+
+UDPSocket::UDPSocket(bool ipv6)
+{
+	init(ipv6, false);
+}
+
+bool UDPSocket::init(bool ipv6, bool noExceptions)
+{
+	if (!g_sockets_initialized) {
+		dstream << "Sockets not initialized" << std::endl;
+		return false;
+	}
+
+	// Use IPv6 if specified
+	m_addr_family = ipv6 ? AF_INET6 : AF_INET;
+	m_handle = socket(m_addr_family, SOCK_DGRAM, IPPROTO_UDP);
+
+	if (socket_enable_debug_output) {
+		dstream << "UDPSocket(" << (int)m_handle
+			<< ")::UDPSocket(): ipv6 = " << (ipv6 ? "true" : "false")
+			<< std::endl;
+	}
+
+	if (m_handle <= 0) {
+		if (noExceptions) {
+			return false;
+		}
+
+		throw SocketException(std::string("Failed to create socket: error ") +
+				      itos(LAST_SOCKET_ERR()));
+	}
+
+	setTimeoutMs(0);
+
+	return true;
+}
+
+UDPSocket::~UDPSocket()
+{
+	if (socket_enable_debug_output) {
+		dstream << "UDPSocket( " << (int)m_handle << ")::~UDPSocket()"
+			<< std::endl;
+	}
+
+#ifdef _WIN32
+	closesocket(m_handle);
+#else
+	close(m_handle);
+#endif
+}
+
+void UDPSocket::Bind(Address addr)
+{
+	if (socket_enable_debug_output) {
+		dstream << "UDPSocket(" << (int)m_handle
+			<< ")::Bind(): " << addr.serializeString() << ":"
+			<< addr.getPort() << std::endl;
+	}
+
+	if (addr.getFamily() != m_addr_family) {
+		static const char *errmsg =
+				"Socket and bind address families do not match";
+		errorstream << "Bind failed: " << errmsg << std::endl;
+		throw SocketException(errmsg);
+	}
+
+	if (m_addr_family == AF_INET6) {
+		struct sockaddr_in6 address;
+		memset(&address, 0, sizeof(address));
+
+		address = addr.getAddress6();
+		address.sin6_family = AF_INET6;
+		address.sin6_port = htons(addr.getPort());
+
+		if (bind(m_handle, (const struct sockaddr *)&address,
+				    sizeof(struct sockaddr_in6)) < 0) {
+			dstream << (int)m_handle << ": Bind failed: " << strerror(errno)
+				<< std::endl;
+			throw SocketException("Failed to bind socket");
+		}
+	} else {
+		struct sockaddr_in address;
+		memset(&address, 0, sizeof(address));
+
+		address = addr.getAddress();
+		address.sin_family = AF_INET;
+		address.sin_port = htons(addr.getPort());
+
+		if (bind(m_handle, (const struct sockaddr *)&address,
+				    sizeof(struct sockaddr_in)) < 0) {
+			dstream << (int)m_handle << ": Bind failed: " << strerror(errno)
+				<< std::endl;
+			throw SocketException("Failed to bind socket");
+		}
+	}
+}
+
+void UDPSocket::Send(const Address &destination, const void *data, int size)
+{
+	bool dumping_packet = false; // for INTERNET_SIMULATOR
+
+	if (INTERNET_SIMULATOR)
+		dumping_packet = myrand() % INTERNET_SIMULATOR_PACKET_LOSS == 0;
+
+	if (socket_enable_debug_output) {
+		// Print packet destination and size
+		dstream << (int)m_handle << " -> ";
+		destination.print(&dstream);
+		dstream << ", size=" << size;
+
+		// Print packet contents
+		dstream << ", data=";
+		for (int i = 0; i < size && i < 20; i++) {
+			if (i % 2 == 0)
+				dstream << " ";
+			unsigned int a = ((const unsigned char *)data)[i];
+			dstream << std::hex << std::setw(2) << std::setfill('0') << a;
+		}
+
+		if (size > 20)
+			dstream << "...";
+
+		if (dumping_packet)
+			dstream << " (DUMPED BY INTERNET_SIMULATOR)";
+
+		dstream << std::endl;
+	}
+
+	if (dumping_packet) {
+		// Lol let's forget it
+		dstream << "UDPSocket::Send(): INTERNET_SIMULATOR: dumping packet."
+			<< std::endl;
+		return;
+	}
+
+	if (destination.getFamily() != m_addr_family)
+		throw SendFailedException("Address family mismatch");
+
+	int sent;
+	if (m_addr_family == AF_INET6) {
+		struct sockaddr_in6 address = destination.getAddress6();
+		address.sin6_port = htons(destination.getPort());
+		sent = sendto(m_handle, (const char *)data, size, 0,
+				(struct sockaddr *)&address, sizeof(struct sockaddr_in6));
+	} else {
+		struct sockaddr_in address = destination.getAddress();
+		address.sin_port = htons(destination.getPort());
+		sent = sendto(m_handle, (const char *)data, size, 0,
+				(struct sockaddr *)&address, sizeof(struct sockaddr_in));
+	}
+
+	if (sent != size)
+		throw SendFailedException("Failed to send packet");
+}
+
+int UDPSocket::Receive(Address &sender, void *data, int size)
+{
+	// Return on timeout
+	if (!WaitData(m_timeout_ms))
+		return -1;
+
+	int received;
+	if (m_addr_family == AF_INET6) {
+		struct sockaddr_in6 address;
+		memset(&address, 0, sizeof(address));
+		socklen_t address_len = sizeof(address);
+
+		received = recvfrom(m_handle, (char *)data, size, 0,
+				(struct sockaddr *)&address, &address_len);
+
+		if (received < 0)
+			return -1;
+
+		u16 address_port = ntohs(address.sin6_port);
+		IPv6AddressBytes bytes;
+		memcpy(bytes.bytes, address.sin6_addr.s6_addr, 16);
+		sender = Address(&bytes, address_port);
+	} else {
+		struct sockaddr_in address;
+		memset(&address, 0, sizeof(address));
+
+		socklen_t address_len = sizeof(address);
+
+		received = recvfrom(m_handle, (char *)data, size, 0,
+				(struct sockaddr *)&address, &address_len);
+
+		if (received < 0)
+			return -1;
+
+		u32 address_ip = ntohl(address.sin_addr.s_addr);
+		u16 address_port = ntohs(address.sin_port);
+
+		sender = Address(address_ip, address_port);
+	}
+
+	if (socket_enable_debug_output) {
+		// Print packet sender and size
+		dstream << (int)m_handle << " <- ";
+		sender.print(&dstream);
+		dstream << ", size=" << received;
+
+		// Print packet contents
+		dstream << ", data=";
+		for (int i = 0; i < received && i < 20; i++) {
+			if (i % 2 == 0)
+				dstream << " ";
+			unsigned int a = ((const unsigned char *)data)[i];
+			dstream << std::hex << std::setw(2) << std::setfill('0') << a;
+		}
+		if (received > 20)
+			dstream << "...";
+
+		dstream << std::endl;
+	}
+
+	return received;
+}
+
+int UDPSocket::GetHandle()
+{
+	return m_handle;
+}
+
+void UDPSocket::setTimeoutMs(int timeout_ms)
+{
+	m_timeout_ms = timeout_ms;
+}
+
+bool UDPSocket::WaitData(int timeout_ms)
+{
+	fd_set readset;
+	int result;
+
+	// Initialize the set
+	FD_ZERO(&readset);
+	FD_SET(m_handle, &readset);
+
+	// Initialize time out struct
+	struct timeval tv;
+	tv.tv_sec = 0;
+	tv.tv_usec = timeout_ms * 1000;
+
+	// select()
+	result = select(m_handle + 1, &readset, NULL, NULL, &tv);
+
+	if (result == 0)
+		return false;
+
+	if (result < 0 && (errno == EINTR || errno == EBADF)) {
+		// N.B. select() fails when sockets are destroyed on Connection's dtor
+		// with EBADF.  Instead of doing tricky synchronization, allow this
+		// thread to exit but don't throw an exception.
+		return false;
+	}
+
+	if (result < 0) {
+		dstream << m_handle << ": Select failed: " << strerror(errno)
+			<< std::endl;
+
+#ifdef _WIN32
+		int e = WSAGetLastError();
+		dstream << (int)m_handle << ": WSAGetLastError()=" << e << std::endl;
+		if (e == 10004 /* WSAEINTR */ || e == 10009 /* WSAEBADF */) {
+			infostream << "Ignoring WSAEINTR/WSAEBADF." << std::endl;
+			return false;
+		}
+#endif
+
+		throw SocketException("Select failed");
+	} else if (!FD_ISSET(m_handle, &readset)) {
+		// No data
+		return false;
+	}
+
+	// There is data
+	return true;
+}