src/socket.cpp


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
/*
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.
*/

#ifndef MODALMENU_HEADER
#define MODALMENU_HEADER

#include "irrlichttypes_extrabloated.h"
#ifdef HAVE_TOUCHSCREENGUI
#include "touchscreengui.h"
#endif

class GUIModalMenu;

class IMenuManager
{
public:
	// A GUIModalMenu calls these when this class is passed as a parameter
	virtual void createdMenu(gui::IGUIElement *menu) = 0;
	virtual void deletingMenu(gui::IGUIElement *menu) = 0;
};

/*
	Remember to drop() the menu after creating, so that it can
	remove itself when it wants to.
*/

class GUIModalMenu : public gui::IGUIElement
{
public:
	GUIModalMenu(gui::IGUIEnvironment* env,
			gui::IGUIElement* parent, s32 id,
			IMenuManager *menumgr):
		IGUIElement(gui::EGUIET_ELEMENT, env, parent, id,
				core::rect<s32>(0,0,100,100))
	{
		//m_force_regenerate_gui = false;
		
		m_menumgr = menumgr;
		m_allow_focus_removal = false;
		m_screensize_old = v2u32(0,0);

		setVisible(true);
		Environment->setFocus(this);
		m_menumgr->createdMenu(this);
	}
	virtual ~GUIModalMenu()
	{
		m_menumgr->deletingMenu(this);
	}

	void allowFocusRemoval(bool allow)
	{
		m_allow_focus_removal = allow;
	}

	bool canTakeFocus(gui::IGUIElement *e)
	{
		return (e && (e == this || isMyChild(e))) || m_allow_focus_removal;
	}

	void draw()
	{
		if(!IsVisible)
			return;
			
		video::IVideoDriver* driver = Environment->getVideoDriver();
		v2u32 screensize = driver->getScreenSize();
		if(screensize != m_screensize_old /*|| m_force_regenerate_gui*/)
		{
			m_screensize_old = screensize;
			regenerateGui(screensize);
			//m_force_regenerate_gui = false;
		}

		drawMenu();
	}
	
	/*
		This should be called when the menu wants to quit.

		WARNING: THIS DEALLOCATES THE MENU FROM MEMORY. Return
		immediately if you call this from the menu itself.

		(More precisely, this decrements the reference count.)
	*/
	void quitMenu()
	{
		allowFocusRemoval(true);
		// This removes Environment's grab on us
		Environment->removeFocus(this);
		m_menumgr->deletingMenu(this);
		this->remove();
#ifdef HAVE_TOUCHSCREENGUI
		if (g_touchscreengui)
			g_touchscreengui->show();
#endif
	}

	void removeChildren()
	{
		const core::list<gui::IGUIElement*> &children = getChildren();
		core::list<gui::IGUIElement*> children_copy;
		for(core::list<gui::IGUIElement*>::ConstIterator
				i = children.begin(); i != children.end(); i++)
		{
			children_copy.push_back(*i);
		}
		for(core::list<gui::IGUIElement*>::Iterator
				i = children_copy.begin();
				i != children_copy.end(); i++)
		{
			(*i)->remove();
		}
	}

	virtual void regenerateGui(v2u32 screensize) = 0;
	virtual void drawMenu() = 0;
	virtual bool preprocessEvent(const SEvent& event) { return false; };
	virtual bool OnEvent(const SEvent& event) { return false; };
	virtual bool pausesGame(){ return false; } // Used for pause menu

protected:
	//bool m_force_regenerate_gui;
	v2u32 m_screensize_old;
private:
	IMenuManager *m_menumgr;
	// This might be necessary to expose to the implementation if it
	// wants to launch other menus
	bool m_allow_focus_removal;
};


#endif
/*
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 <stdio.h>
#include <iostream>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#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
	#ifndef WIN32_LEAN_AND_MEAN
		#define WIN32_LEAN_AND_MEAN
	#endif
	// 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
}

/*
	Address
*/

Address::Address()
{
	m_addr_family = 0;
	memset(&m_address, 0, sizeof(m_address));
	m_port = 0;
}

Address::Address(u32 address, u16 port)
{
	memset(&m_address, 0, sizeof(m_address));
	setAddress(address);
	setPort(port);
}

Address::Address(u8 a, u8 b, u8 c, u8 d, u16 port)
{
	memset(&m_address, 0, sizeof(m_address));
	setAddress(a, b, c, d);
	setPort(port);
}

Address::Address(const IPv6AddressBytes *ipv6_bytes, u16 port)
{
	memset(&m_address, 0, sizeof(m_address));
	setAddress(ipv6_bytes);
	setPort(port);
}

// Equality (address family, address and port must be equal)
bool Address::operator==(const Address &address)
{
	if(address.m_addr_family != m_addr_family || address.m_port != m_port)
		return false;
	else if(m_addr_family == AF_INET)
	{
		return m_address.ipv4.sin_addr.s_addr ==
		       address.m_address.ipv4.sin_addr.s_addr;
	}
	else if(m_addr_family == AF_INET6)
	{
		return memcmp(m_address.ipv6.sin6_addr.s6_addr,
		              address.m_address.ipv6.sin6_addr.s6_addr, 16) == 0;
	}
	else
		return false;
}

bool Address::operator!=(const Address &address)
{
	return !(*this == address);
}

void Address::Resolve(const char *name)
{
	if (!name || name[0] == 0) {
		if (m_addr_family == AF_INET) {
			setAddress((u32) 0);
		} else if (m_addr_family == AF_INET6) {
			setAddress((IPv6AddressBytes*) 0);
		}
		return;
	}

	struct addrinfo *resolved, hints;
	memset(&hints, 0, sizeof(hints));

	// Setup hints
	hints.ai_socktype = 0;
	hints.ai_protocol = 0;
	hints.ai_flags    = 0;
	if(g_settings->getBool("enable_ipv6"))
	{
		// AF_UNSPEC allows both IPv6 and IPv4 addresses to be returned
		hints.ai_family = AF_UNSPEC;
	}
	else
	{
		hints.ai_family = AF_INET;
	}

	// Do getaddrinfo()
	int e = getaddrinfo(name, NULL, &hints, &resolved);
	if(e != 0)
		throw ResolveError(gai_strerror(e));

	// Copy data
	if(resolved->ai_family == AF_INET)
	{
		struct sockaddr_in *t = (struct sockaddr_in *) resolved->ai_addr;
		m_addr_family = AF_INET;
		m_address.ipv4 = *t;
	}
	else if(resolved->ai_family == AF_INET6)
	{
		struct sockaddr_in6 *t = (struct sockaddr_in6 *) resolved->ai_addr;
		m_addr_family = AF_INET6;
		m_address.ipv6 = *t;
	}
	else
	{
		freeaddrinfo(resolved);
		throw ResolveError("");
	}
	freeaddrinfo(resolved);
}

// IP address -> textual representation
std::string Address::serializeString() const
{
// windows XP doesnt have inet_ntop, maybe use better func
#ifdef _WIN32
	if(m_addr_family == AF_INET)
	{
		u8 a, b, c, d;
		u32 addr;
		addr = ntohl(m_address.ipv4.sin_addr.s_addr);
		a = (addr & 0xFF000000) >> 24;
		b = (addr & 0x00FF0000) >> 16;
		c = (addr & 0x0000FF00) >> 8;
		d = (addr & 0x000000FF);
		return itos(a) + "." + itos(b) + "." + itos(c) + "." + itos(d);
	}
	else if(m_addr_family == AF_INET6)
	{
		std::ostringstream os;
		for(int i = 0; i < 16; i += 2)
		{
			u16 section =
			(m_address.ipv6.sin6_addr.s6_addr[i] << 8) |
			(m_address.ipv6.sin6_addr.s6_addr[i + 1]);
			os << std::hex << section;
			if(i < 14)
				os << ":";
		}
		return os.str();
	}
	else
		return std::string("");
#else
	char str[INET6_ADDRSTRLEN];
	if (inet_ntop(m_addr_family, (m_addr_family == AF_INET) ? (void*)&(m_address.ipv4.sin_addr) : (void*)&(m_address.ipv6.sin6_addr), str, INET6_ADDRSTRLEN) == NULL) {
		return std::string("");
	}
	return std::string(str);
#endif
}

struct sockaddr_in Address::getAddress() const
{
	return m_address.ipv4; // NOTE: NO PORT INCLUDED, use getPort()
}

struct sockaddr_in6 Address::getAddress6() const
{
	return m_address.ipv6; // NOTE: NO PORT INCLUDED, use getPort()
}

u16 Address::getPort() const
{
	return m_port;
}

int Address::getFamily() const
{
	return m_addr_family;
}

bool Address::isIPv6() const
{
	return m_addr_family == AF_INET6;
}

bool Address::isZero() const
{
	if (m_addr_family == AF_INET) {
		return m_address.ipv4.sin_addr.s_addr == 0;
	} else if (m_addr_family == AF_INET6) {
		static const char zero[16] = {0};
		return memcmp(m_address.ipv6.sin6_addr.s6_addr,
		              zero, 16) == 0;
	}
	return false;
}

void Address::setAddress(u32 address)
{
	m_addr_family = AF_INET;
	m_address.ipv4.sin_family = AF_INET;
	m_address.ipv4.sin_addr.s_addr = htonl(address);
}

void Address::setAddress(u8 a, u8 b, u8 c, u8 d)
{
	m_addr_family = AF_INET;
	m_address.ipv4.sin_family = AF_INET;
	u32 addr = htonl((a << 24) | (b << 16) | (c << 8) | d);
	m_address.ipv4.sin_addr.s_addr = addr;
}

void Address::setAddress(const IPv6AddressBytes *ipv6_bytes)
{
	m_addr_family = AF_INET6;
	m_address.ipv6.sin6_family = AF_INET6;
	if (ipv6_bytes)
		memcpy(m_address.ipv6.sin6_addr.s6_addr, ipv6_bytes->bytes, 16);
	else
		memset(m_address.ipv6.sin6_addr.s6_addr, 0, 16);
}

void Address::setPort(u16 port)
{
	m_port = port;
}

void Address::print(std::ostream *s) const
{
	if(m_addr_family == AF_INET6)
		*s << "[" << serializeString() << "]:" << m_port;
	else
		*s << serializeString() << ":" << m_port;
}

/*
	UDPSocket
*/

UDPSocket::UDPSocket(bool ipv6)
{
	init(ipv6, false);
}

bool UDPSocket::init(bool ipv6, bool noExceptions)
{
	if (g_sockets_initialized == false) {
		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;
		} else {
			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) == false)
		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;
	else 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;
	} else if (result < 0) {
		dstream << (int) 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) == false) {
		// No data
		return false;
	}

	// There is data
	return true;
}