server/socket/lowlevel.C

/*
 * This file is part of Deliantra, the Roguelike Realtime MMORPG.
 *
 * Copyright (©) 2005,2006,2007,2008,2009,2010,2011,2012 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
 *
 * Deliantra is free software: you can redistribute it and/or modify it under
 * the terms of the Affero GNU General Public License as published by the
 * Free Software Foundation, either version 3 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 General Public License for more details.
 *
 * You should have received a copy of the Affero GNU General Public License
 * and the GNU General Public License along with this program. If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * The authors can be reached via e-mail to <support@deliantra.net>
 */

using namespace std;

#include <global.h>
#include <sproto.h>
#include <cstdarg>

#if HAVE_TCP_INFO
# include <sys/types.h>
# include <sys/socket.h>
# include <netinet/in.h>
# include <netinet/tcp.h>
#endif

// force a packet when idle for more than this many seconds,
// forcing an ack regularly.
#define IDLE_PING 2.

void
client::flush ()
{
  if (destroyed ())
    return;

  /**
   * Writes data to socket.
   *
   * When the socket is clear to write, and we have backlogged data, this
   * is called to write it out.
   */

  // write a nop to the socket at least every IDLE_NOP seconds.
  if (!outputbuffer.len)
    {
      if (last_send + IDLE_PING <= NOW && pl && pl->active)
        {
          // this is a bit ugly, but map1a seems to be the only
          // nop'able command and it is quite small.
          packet sl ("map1a");
          send_packet (sl);
        }
      else
        return;
    }

  if (socket_ev.poll () & EV_WRITE)
    return;

  last_send = NOW;
  write_outputbuffer ();
}

void
client::write_outputbuffer ()
{
  while (outputbuffer.len)
    {
      int res = write (fd, outputbuffer.data + outputbuffer.start,
                       min (outputbuffer.len, SOCKETBUFSIZE - outputbuffer.start));

      if (res > 0)
        {
          outputbuffer.start += res;
          /* wrap back to start of buffer */
          if (outputbuffer.start == SOCKETBUFSIZE)
            outputbuffer.start = 0;

          outputbuffer.len -= res;
        }
      else if (res == 0)
        {
          LOG (llevError, "socket write failed, connection closed.\n");
          destroy ();
          return;
        }
      else if (errno == EINTR)
        {
          // just retry
        }
      else if (errno == EAGAIN)
        {
          // delay till ready
          socket_ev.poll (socket_ev.poll () | EV_WRITE);
          socket_ev.start ();
          return;
        }
      else
        {
          LOG (llevError, "socket write failed: %s\n", strerror (errno));
          destroy ();
          return;
        }
    }

  socket_ev.poll (socket_ev.poll () & ~EV_WRITE);
}

/******************************************************************************
 *
 * Start of read routines.
 *
 ******************************************************************************/

int
client::next_packet ()
{
  if (inbuf_len >= 2)
    {
      int pkt_len = (inbuf [0] << 8) | inbuf [1];

      if (inbuf_len >= 2 + pkt_len)
        return 2 + pkt_len;

      if (inbuf_len == sizeof (inbuf))
        {
          send_packet_printf ("drawinfo %d input buffer overflow - closing connection.", NDI_RED | NDI_REPLY);
          destroy ();
          return -1;
        }
    }

  return 0;
}

void
client::skip_packet (int len)
{
  inbuf_len -= len;
  memmove (inbuf, inbuf + len, inbuf_len);
}

/*****************************************************************************
 * Start of command dispatch area.
 * The commands here are protocol commands. 
 ****************************************************************************/

// SocketCommand, PlayingCommand, should not exist with those ugly casts
#define SC(cb) (void *)static_cast<void (*)(char *, int, client *)>(cb),
#define PC(cb) (void *)static_cast<void (*)(char *, int, player *)>(cb), PF_PLAYER |

static void
NopCmd (char *, int, client *)
{
  // do nothing
}

/**
 * Dispatch table for the server.
 */
static struct packet_type packets[] = {
  {"ncom",        PC(NewPlayerCmd) PF_PLAYING | PF_COMMAND6 },
  {"command",     PC(PlayerCmd)    PF_PLAYING | PF_COMMAND0 },

  {"examine",     PC(ExamineCmd)   PF_PLAYING },
  {"ex",          PC(ExCmd)        PF_PLAYING },
  {"apply",       PC(ApplyCmd)     PF_PLAYING },
  {"lookat",      PC(LookAt)       PF_PLAYING },
  {"lock",        PC(LockItem)     PF_PLAYING },
  {"mark",        PC(MarkItem)     PF_PLAYING },
  {"move",        PC(MoveCmd)      PF_PLAYING },
  {"ext",         PC(ExtCmd)       0 }, // CF+/Deliantra
  {"mapredraw",   PC(MapRedrawCmd) 0 },
  {"mapinfo",     PC(MapInfoCmd)   0 }, // CF+/Deliantra

  {"reply",       SC(ReplyCmd)     0 },
  {"exti",        SC(ExtiCmd)      0 }, // CF+/Deliantra
  {"addme",       SC(AddMeCmd)     0 },
  {"askface",     SC(AskFaceCmd)   0 },
  {"requestinfo", SC(RequestInfo)  0 },
  {"setsound",    SC(SetSound)     0 },
  {"setup",       SC(SetUp)        0 },
  {"version",     SC(VersionCmd)   0 },

  {"toggleextendedtext", SC(NopCmd)   0 }, // deliantra: disabled
};

bool
client::may_execute (const packet_type *pkt) const
{
  return (!(pkt->flags & PF_PLAYER)  || pl)
      && (!(pkt->flags & PF_PLAYING) || state == ST_PLAYING);
}

// HACK: some commands currently should be executed 
// even when the player is frozen. this hack detects
// those commands. it should be folded into may_execute,
// but kept seperate to emphasise the hack aspect, i.e.
// do it better, then remove.
static bool
always_immediate (const client *ns, const packet_type *pkt, const char *data, int len)
{
  if (!(pkt->flags & (PF_COMMAND0 | PF_COMMAND6)))
    return false;

  if (!ns->pl || !ns->pl->ob || !ns->pl->ob->map)
    return false;

  if (pkt->flags & PF_COMMAND6)
    {
      data += 6;
      len  -= 6;
    }

  if (len >  4 && data [ 3] == ' ' && !strncmp (data, "say "              ,  4)) return true;
  if (len >  5 && data [ 4] == ' ' && !strncmp (data, "chat "             ,  5)) return true;
  if (len >  6 && data [ 5] == ' ' && !strncmp (data, "shout "            ,  6)) return true;
  if (len >  8 && data [ 7] == ' ' && !strncmp (data, "suicide "          ,  8)) return true;
  if (len > 18 && data [17] == ' ' && !strncmp (data, "accept-invitation ", 18)) return true;

  if (len == 7 && !strcmp (data, "suicide")) return true;

  return false;
}

void
client::execute (const packet_type *pkt, char *data, int datalen)
{
  if (may_execute (pkt) || always_immediate (this, pkt, data, datalen))
    {
      //TODO: only one format
      if (pkt->flags & PF_PLAYER)
        {
          ((void (*)(char *, int, player *))pkt->cb)((char *)data, datalen, pl);
          pl->need_updated_stats ();
        }
      else
        ((void (*)(char *, int, client *))pkt->cb)((char *)data, datalen, this);
    }
  else
    send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED | NDI_REPLY, pkt->name);
}

bool
client::handle_packet ()
{
  int pkt_len = next_packet ();

  if (!pkt_len)
    return false;
  else if (pkt_len < 0)
    {
      LOG (llevError, "read error on player %s\n",
                      pl && pl->ob ? &pl->ob->name : "[anonymous]");
      destroy ();
      return false;
    }

  uint8_t save_byte = inbuf [pkt_len]; // rather ugly
  inbuf [pkt_len] = 0;      /* temporarily terminate buffer - useful for string data */

  /* First, break out beginning word.  There are at least
   * a few commands that do not have any paremeters.  If
   * we get such a command, don't worry about trying
   * to break it up.
   */
  int datalen;
  char *data = strchr ((char *)inbuf + 2, ' ');

  if (data)
    {
      *data++ = 0;
      datalen = pkt_len - (data - (char *)inbuf);
    }
  else
    {
      data = (char *)inbuf + 2; // better read garbage than segfault
      datalen = 0;
    }

  for (packet_type *pkt = packets; pkt < packets + array_length (packets); ++pkt)
    if (!strcmp ((char *)inbuf + 2, pkt->name))
      {
        if (pkt->flags & PF_PLAYER && !always_immediate (this, pkt, data, datalen))
          queue_command (pkt, data, datalen);
        else
          execute (pkt, data, datalen);

        goto next_packet;
      }

  // If we get here, we didn't find a valid command.
  send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED | NDI_REPLY, (char *)inbuf + 2);

next_packet:
  inbuf [pkt_len] = save_byte; // rather ugly
  skip_packet (pkt_len);

  // input buffer has space again
  socket_ev.poll (socket_ev.poll () | EV_READ);

  return true;
}

void
client::inbuf_handle ()
{
  if (!handle_packet ())
    return;

  while (handle_packet ())
    ;

  flush ();
}

// callback called when socket is either readable or writable
void
client::socket_cb (iow &w, int revents)
{
  //TODO remove when we have better socket cleanup logic
  if (destroyed ())
    {
      socket_ev.poll (0);
      return;
    }

  if (revents & EV_WRITE)
    {
      write_outputbuffer ();

      if (!outputbuffer.len)
        socket_ev.poll (socket_ev.poll () & ~EV_WRITE);
    }

  if (revents & EV_READ)
    {
      //TODO: rate-limit tcp connection in better ways, important

      int amount = sizeof (inbuf) - inbuf_len;

      if (!amount)
        {
          // input buffer full
          socket_ev.poll (socket_ev.poll () & ~EV_READ);
          return;
        }

      amount = read (fd, inbuf + inbuf_len, amount);

      if (!amount)
        {
          destroy ();
          return;
        }
      else if (amount < 0)
        {
          if (errno != EAGAIN && errno != EINTR)
            {
              LOG (llevError, "read error: %s\n", strerror (errno));
              destroy ();
              return;
            }

          // should not be here, normally
        }
      else
        {
          inbuf_len += amount;
          inbuf_handle ();
        }
    }
}

/*******************************************************************************
 *
 * Start of write related routines.
 *
 ******************************************************************************/

/**
 * Adds data to a socket buffer for whatever reason.
 *
 * ns is the socket we are adding the data to, buf is the start of the
 * data, and len is the number of bytes to add.
 */
void
client::send (void *buf_, int len)
{
  char *buf = (char *)buf_;

  if (destroyed () || !buf)
    return;

  if (len + outputbuffer.len > SOCKETBUFSIZE)
    {
      LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
      // shutdown the socket, this is safer than destroying it immediately
      // as lots of code in the callchain might still access the map etc.
      shutdown (fd, SHUT_RDWR);
      return;
    }

  int avail, end;

  /* data + end is where we start putting the new data.  The last byte
   * currently in use is actually data + end -1
   */
  end = outputbuffer.start + outputbuffer.len;
  /* The buffer is already in a wrapped state, so adjust end */
  if (end >= SOCKETBUFSIZE)
    end -= SOCKETBUFSIZE;

  avail = SOCKETBUFSIZE - end;

  /* We can all fit it behind the current data without wrapping */
  if (avail >= len)
    memcpy (outputbuffer.data + end, buf, len);
  else
    {
      memcpy (outputbuffer.data + end, buf, avail);
      memcpy (outputbuffer.data, buf + avail, len - avail);
    }

  outputbuffer.len += len;
}

/**
 * Takes a string of data, and writes it out to the socket. A very handy
 * shortcut function.
 */
void
client::send_packet (packet &sl)
{
  if (destroyed ())
    return;

  if (sl.length () > MAXSOCKBUF)
    {
      LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
      /* Almost certainly we've overflowed a buffer, so quit now to make
       * it easier to debug.
       */
      abort ();
    }

  if (!sl.length ())
    return;

  assert (sl.hdrlen == 2);

  sl.buf_ [0] = sl.length () >> 8;
  sl.buf_ [1] = sl.length ()     ;

  send (sl.buf_, sl.length () + sl.hdrlen);
}

void
client::send_packet (const char *buf, int len)
{
  packet sl;

  sl << data (buf, len);
  send_packet (sl);
}

void
client::send_packet (const char *buf)
{
  send_packet (buf, strlen (buf));
}

void
client::send_packet_printf (const char *format, ...)
{
  packet sl;

  va_list ap;
  va_start (ap, format);
  sl.vprintf (format, ap);
  va_end (ap);

  send_packet (sl);
}

void
client::send_msg (int color, const char *type, const char *msg)
{
  if (!msg || !type) // it can happen (for example, missing attack messages cause this)
    {
      LOG (logBacktrace | llevError, "send_msg(%d,%p,%p) called with NULL msg or type.\n", color, type, msg);
      return;
    }

  int len = strlen (msg);

  if (!(color & NDI_VERBATIM)
      && (msg_is_special (msg)
          || (type [0] == 'c' && type [1] == '/') || len > (MAXSOCKBUF - 128)))
    cfperl_send_msg (this, color, type, msg);
  else
    send_packet_printf ("msg %d %s %s", color & NDI_CLIENT_MASK, type, msg);
}

void
client::send_drawinfo (const char *msg, int flags)
{
  send_msg (flags, "log", msg);
}

/***********************************************************************
 *
 * packet functions/utilities
 *
 **********************************************************************/

packet::packet (const char *name)
{
  reset ();

  int len = strlen (name);
  memcpy (cur, name, len); cur += len;
  *cur++ = ' ';
}

packet &packet::operator <<(const ber32 v)
{
  enum { maxlen = 32 / 7 + 1 };
  uint8 buf[maxlen];
  uint8 *p = buf + maxlen;
  uint32 val = v.val;

  *--p = val & 0x7F;

  while (val > 0x7F)
    {
      val >>= 7;
      *--p = (val & 0x7F) | 0x80;
    }

  return *this << data (p, buf + maxlen - p);
}

packet &packet::operator <<(const data   &v)
{
  if (room () < v.len)
    reset ();
  else
    {
      if (v.len)
        {
          memcpy (cur, v.ptr, v.len);
          cur += v.len;
        }
    }

  return *this;
}

packet &packet::operator <<(const data8  &v)
{
  unsigned int len = min (v.len, 0x00FF);
  return *this << uint8  (len) << data (v.ptr, len);
}

packet &packet::operator <<(const data16 &v)
{
  unsigned int len = min (v.len, 0xFFFF);
  return *this << uint16 (len) << data (v.ptr, len);
}

packet &packet::operator <<(const char *v)
{
  return *this << data (v, strlen (v ? v : 0));
}

void
packet::vprintf (const char *format, va_list ap)
{
  int size = room ();

  int len = vsnprintf ((char *)cur, size, format, ap);

  if (len >= size)
    return reset ();

  cur += len;
}

Revision:	1.86
Committed:	Tue Oct 30 17:07:50 2012 UTC (11 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.85:	+13 -8 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* This file is part of Deliantra, the Roguelike Realtime MMORPG.
3	*
4	* Copyright (©) 2005,2006,2007,2008,2009,2010,2011,2012 Marc Alexander Lehmann / Robin Redeker / the Deliantra team
5	*
6	* Deliantra is free software: you can redistribute it and/or modify it under
7	* the terms of the Affero GNU General Public License as published by the
8	* Free Software Foundation, either version 3 of the License, or (at your
9	* option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the Affero GNU General Public License
17	* and the GNU General Public License along with this program. If not, see
18	* <http://www.gnu.org/licenses/>.
19	*
20	* The authors can be reached via e-mail to <support@deliantra.net>
21	*/
22
23	using namespace std;
24
25	#include <global.h>
26	#include <sproto.h>
27	#include <cstdarg>
28
29	#if HAVE_TCP_INFO
30	# include <sys/types.h>
31	# include <sys/socket.h>
32	# include <netinet/in.h>
33	# include <netinet/tcp.h>
34	#endif
35
36	// force a packet when idle for more than this many seconds,
37	// forcing an ack regularly.
38	#define IDLE_PING 2.
39
40	void
41	client::flush ()
42	{
43	if (destroyed ())
44	return;
45
46	/**
47	* Writes data to socket.
48	*
49	* When the socket is clear to write, and we have backlogged data, this
50	* is called to write it out.
51	*/
52
53	// write a nop to the socket at least every IDLE_NOP seconds.
54	if (!outputbuffer.len)
55	{
56	if (last_send + IDLE_PING <= NOW && pl && pl->active)
57	{
58	// this is a bit ugly, but map1a seems to be the only
59	// nop'able command and it is quite small.
60	packet sl ("map1a");
61	send_packet (sl);
62	}
63	else
64	return;
65	}
66
67	if (socket_ev.poll () & EV_WRITE)
68	return;
69
70	last_send = NOW;
71	write_outputbuffer ();
72	}
73
74	void
75	client::write_outputbuffer ()
76	{
77	while (outputbuffer.len)
78	{
79	int res = write (fd, outputbuffer.data + outputbuffer.start,
80	min (outputbuffer.len, SOCKETBUFSIZE - outputbuffer.start));
81
82	if (res > 0)
83	{
84	outputbuffer.start += res;
85	/* wrap back to start of buffer */
86	if (outputbuffer.start == SOCKETBUFSIZE)
87	outputbuffer.start = 0;
88
89	outputbuffer.len -= res;
90	}
91	else if (res == 0)
92	{
93	LOG (llevError, "socket write failed, connection closed.\n");
94	destroy ();
95	return;
96	}
97	else if (errno == EINTR)
98	{
99	// just retry
100	}
101	else if (errno == EAGAIN)
102	{
103	// delay till ready
104	socket_ev.poll (socket_ev.poll () \| EV_WRITE);
105	socket_ev.start ();
106	return;
107	}
108	else
109	{
110	LOG (llevError, "socket write failed: %s\n", strerror (errno));
111	destroy ();
112	return;
113	}
114	}
115
116	socket_ev.poll (socket_ev.poll () & ~EV_WRITE);
117	}
118
119	/******************************************************************************
120	*
121	* Start of read routines.
122	*
123	******************************************************************************/
124
125	int
126	client::next_packet ()
127	{
128	if (inbuf_len >= 2)
129	{
130	int pkt_len = (inbuf [0] << 8) \| inbuf [1];
131
132	if (inbuf_len >= 2 + pkt_len)
133	return 2 + pkt_len;
134
135	if (inbuf_len == sizeof (inbuf))
136	{
137	send_packet_printf ("drawinfo %d input buffer overflow - closing connection.", NDI_RED \| NDI_REPLY);
138	destroy ();
139	return -1;
140	}
141	}
142
143	return 0;
144	}
145
146	void
147	client::skip_packet (int len)
148	{
149	inbuf_len -= len;
150	memmove (inbuf, inbuf + len, inbuf_len);
151	}
152
153	/*****************************************************************************
154	* Start of command dispatch area.
155	* The commands here are protocol commands.
156	****************************************************************************/
157
158	// SocketCommand, PlayingCommand, should not exist with those ugly casts
159	#define SC(cb) (void )static_cast<void ()(char , int, client )>(cb),
160	#define PC(cb) (void )static_cast<void ()(char , int, player )>(cb), PF_PLAYER \|
161
162	static void
163	NopCmd (char , int, client )
164	{
165	// do nothing
166	}
167
168	/**
169	* Dispatch table for the server.
170	*/
171	static struct packet_type packets[] = {
172	{"ncom", PC(NewPlayerCmd) PF_PLAYING \| PF_COMMAND6 },
173	{"command", PC(PlayerCmd) PF_PLAYING \| PF_COMMAND0 },
174
175	{"examine", PC(ExamineCmd) PF_PLAYING },
176	{"ex", PC(ExCmd) PF_PLAYING },
177	{"apply", PC(ApplyCmd) PF_PLAYING },
178	{"lookat", PC(LookAt) PF_PLAYING },
179	{"lock", PC(LockItem) PF_PLAYING },
180	{"mark", PC(MarkItem) PF_PLAYING },
181	{"move", PC(MoveCmd) PF_PLAYING },
182	{"ext", PC(ExtCmd) 0 }, // CF+/Deliantra
183	{"mapredraw", PC(MapRedrawCmd) 0 },
184	{"mapinfo", PC(MapInfoCmd) 0 }, // CF+/Deliantra
185
186	{"reply", SC(ReplyCmd) 0 },
187	{"exti", SC(ExtiCmd) 0 }, // CF+/Deliantra
188	{"addme", SC(AddMeCmd) 0 },
189	{"askface", SC(AskFaceCmd) 0 },
190	{"requestinfo", SC(RequestInfo) 0 },
191	{"setsound", SC(SetSound) 0 },
192	{"setup", SC(SetUp) 0 },
193	{"version", SC(VersionCmd) 0 },
194
195	{"toggleextendedtext", SC(NopCmd) 0 }, // deliantra: disabled
196	};
197
198	bool
199	client::may_execute (const packet_type *pkt) const
200	{
201	return (!(pkt->flags & PF_PLAYER) \|\| pl)
202	&& (!(pkt->flags & PF_PLAYING) \|\| state == ST_PLAYING);
203	}
204
205	// HACK: some commands currently should be executed
206	// even when the player is frozen. this hack detects
207	// those commands. it should be folded into may_execute,
208	// but kept seperate to emphasise the hack aspect, i.e.
209	// do it better, then remove.
210	static bool
211	always_immediate (const client ns, const packet_type pkt, const char *data, int len)
212	{
213	if (!(pkt->flags & (PF_COMMAND0 \| PF_COMMAND6)))
214	return false;
215
216	if (!ns->pl \|\| !ns->pl->ob \|\| !ns->pl->ob->map)
217	return false;
218
219	if (pkt->flags & PF_COMMAND6)
220	{
221	data += 6;
222	len -= 6;
223	}
224
225	if (len > 4 && data [ 3] == ' ' && !strncmp (data, "say " , 4)) return true;
226	if (len > 5 && data [ 4] == ' ' && !strncmp (data, "chat " , 5)) return true;
227	if (len > 6 && data [ 5] == ' ' && !strncmp (data, "shout " , 6)) return true;
228	if (len > 8 && data [ 7] == ' ' && !strncmp (data, "suicide " , 8)) return true;
229	if (len > 18 && data [17] == ' ' && !strncmp (data, "accept-invitation ", 18)) return true;
230
231	if (len == 7 && !strcmp (data, "suicide")) return true;
232
233	return false;
234	}
235
236	void
237	client::execute (const packet_type pkt, char data, int datalen)
238	{
239	if (may_execute (pkt) \|\| always_immediate (this, pkt, data, datalen))
240	{
241	//TODO: only one format
242	if (pkt->flags & PF_PLAYER)
243	{
244	((void ()(char , int, player ))pkt->cb)((char )data, datalen, pl);
245	pl->need_updated_stats ();
246	}
247	else
248	((void ()(char , int, client ))pkt->cb)((char )data, datalen, this);
249	}
250	else
251	send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED \| NDI_REPLY, pkt->name);
252	}
253
254	bool
255	client::handle_packet ()
256	{
257	int pkt_len = next_packet ();
258
259	if (!pkt_len)
260	return false;
261	else if (pkt_len < 0)
262	{
263	LOG (llevError, "read error on player %s\n",
264	pl && pl->ob ? &pl->ob->name : "[anonymous]");
265	destroy ();
266	return false;
267	}
268
269	uint8_t save_byte = inbuf [pkt_len]; // rather ugly
270	inbuf [pkt_len] = 0; /* temporarily terminate buffer - useful for string data */
271
272	/* First, break out beginning word. There are at least
273	* a few commands that do not have any paremeters. If
274	* we get such a command, don't worry about trying
275	* to break it up.
276	*/
277	int datalen;
278	char data = strchr ((char )inbuf + 2, ' ');
279
280	if (data)
281	{
282	*data++ = 0;
283	datalen = pkt_len - (data - (char *)inbuf);
284	}
285	else
286	{
287	data = (char *)inbuf + 2; // better read garbage than segfault
288	datalen = 0;
289	}
290
291	for (packet_type *pkt = packets; pkt < packets + array_length (packets); ++pkt)
292	if (!strcmp ((char *)inbuf + 2, pkt->name))
293	{
294	if (pkt->flags & PF_PLAYER && !always_immediate (this, pkt, data, datalen))
295	queue_command (pkt, data, datalen);
296	else
297	execute (pkt, data, datalen);
298
299	goto next_packet;
300	}
301
302	// If we get here, we didn't find a valid command.
303	send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED \| NDI_REPLY, (char *)inbuf + 2);
304
305	next_packet:
306	inbuf [pkt_len] = save_byte; // rather ugly
307	skip_packet (pkt_len);
308
309	// input buffer has space again
310	socket_ev.poll (socket_ev.poll () \| EV_READ);
311
312	return true;
313	}
314
315	void
316	client::inbuf_handle ()
317	{
318	if (!handle_packet ())
319	return;
320
321	while (handle_packet ())
322	;
323
324	flush ();
325	}
326
327	// callback called when socket is either readable or writable
328	void
329	client::socket_cb (iow &w, int revents)
330	{
331	//TODO remove when we have better socket cleanup logic
332	if (destroyed ())
333	{
334	socket_ev.poll (0);
335	return;
336	}
337
338	if (revents & EV_WRITE)
339	{
340	write_outputbuffer ();
341
342	if (!outputbuffer.len)
343	socket_ev.poll (socket_ev.poll () & ~EV_WRITE);
344	}
345
346	if (revents & EV_READ)
347	{
348	//TODO: rate-limit tcp connection in better ways, important
349
350	int amount = sizeof (inbuf) - inbuf_len;
351
352	if (!amount)
353	{
354	// input buffer full
355	socket_ev.poll (socket_ev.poll () & ~EV_READ);
356	return;
357	}
358
359	amount = read (fd, inbuf + inbuf_len, amount);
360
361	if (!amount)
362	{
363	destroy ();
364	return;
365	}
366	else if (amount < 0)
367	{
368	if (errno != EAGAIN && errno != EINTR)
369	{
370	LOG (llevError, "read error: %s\n", strerror (errno));
371	destroy ();
372	return;
373	}
374
375	// should not be here, normally
376	}
377	else
378	{
379	inbuf_len += amount;
380	inbuf_handle ();
381	}
382	}
383	}
384
385	/*******************************************************************************
386	*
387	* Start of write related routines.
388	*
389	******************************************************************************/
390
391	/**
392	* Adds data to a socket buffer for whatever reason.
393	*
394	* ns is the socket we are adding the data to, buf is the start of the
395	* data, and len is the number of bytes to add.
396	*/
397	void
398	client::send (void *buf_, int len)
399	{
400	char buf = (char )buf_;
401
402	if (destroyed () \|\| !buf)
403	return;
404
405	if (len + outputbuffer.len > SOCKETBUFSIZE)
406	{
407	LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
408	// shutdown the socket, this is safer than destroying it immediately
409	// as lots of code in the callchain might still access the map etc.
410	shutdown (fd, SHUT_RDWR);
411	return;
412	}
413
414	int avail, end;
415
416	/* data + end is where we start putting the new data. The last byte
417	* currently in use is actually data + end -1
418	*/
419	end = outputbuffer.start + outputbuffer.len;
420	/* The buffer is already in a wrapped state, so adjust end */
421	if (end >= SOCKETBUFSIZE)
422	end -= SOCKETBUFSIZE;
423
424	avail = SOCKETBUFSIZE - end;
425
426	/* We can all fit it behind the current data without wrapping */
427	if (avail >= len)
428	memcpy (outputbuffer.data + end, buf, len);
429	else
430	{
431	memcpy (outputbuffer.data + end, buf, avail);
432	memcpy (outputbuffer.data, buf + avail, len - avail);
433	}
434
435	outputbuffer.len += len;
436	}
437
438	/**
439	* Takes a string of data, and writes it out to the socket. A very handy
440	* shortcut function.
441	*/
442	void
443	client::send_packet (packet &sl)
444	{
445	if (destroyed ())
446	return;
447
448	if (sl.length () > MAXSOCKBUF)
449	{
450	LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
451	/* Almost certainly we've overflowed a buffer, so quit now to make
452	* it easier to debug.
453	*/
454	abort ();
455	}
456
457	if (!sl.length ())
458	return;
459
460	assert (sl.hdrlen == 2);
461
462	sl.buf_ [0] = sl.length () >> 8;
463	sl.buf_ [1] = sl.length () ;
464
465	send (sl.buf_, sl.length () + sl.hdrlen);
466	}
467
468	void
469	client::send_packet (const char *buf, int len)
470	{
471	packet sl;
472
473	sl << data (buf, len);
474	send_packet (sl);
475	}
476
477	void
478	client::send_packet (const char *buf)
479	{
480	send_packet (buf, strlen (buf));
481	}
482
483	void
484	client::send_packet_printf (const char *format, ...)
485	{
486	packet sl;
487
488	va_list ap;
489	va_start (ap, format);
490	sl.vprintf (format, ap);
491	va_end (ap);
492
493	send_packet (sl);
494	}
495
496	void
497	client::send_msg (int color, const char type, const char msg)
498	{
499	if (!msg \|\| !type) // it can happen (for example, missing attack messages cause this)
500	{
501	LOG (logBacktrace \| llevError, "send_msg(%d,%p,%p) called with NULL msg or type.\n", color, type, msg);
502	return;
503	}
504
505	int len = strlen (msg);
506
507	if (!(color & NDI_VERBATIM)
508	&& (msg_is_special (msg)
509	\|\| (type [0] == 'c' && type [1] == '/') \|\| len > (MAXSOCKBUF - 128)))
510	cfperl_send_msg (this, color, type, msg);
511	else
512	send_packet_printf ("msg %d %s %s", color & NDI_CLIENT_MASK, type, msg);
513	}
514
515	void
516	client::send_drawinfo (const char *msg, int flags)
517	{
518	send_msg (flags, "log", msg);
519	}
520
521	/***********************************************************************
522	*
523	* packet functions/utilities
524	*
525	**********************************************************************/
526
527	packet::packet (const char *name)
528	{
529	reset ();
530
531	int len = strlen (name);
532	memcpy (cur, name, len); cur += len;
533	*cur++ = ' ';
534	}
535
536	packet &packet::operator <<(const ber32 v)
537	{
538	enum { maxlen = 32 / 7 + 1 };
539	uint8 buf[maxlen];
540	uint8 *p = buf + maxlen;
541	uint32 val = v.val;
542
543	*--p = val & 0x7F;
544
545	while (val > 0x7F)
546	{
547	val >>= 7;
548	*--p = (val & 0x7F) \| 0x80;
549	}
550
551	return *this << data (p, buf + maxlen - p);
552	}
553
554	packet &packet::operator <<(const data &v)
555	{
556	if (room () < v.len)
557	reset ();
558	else
559	{
560	if (v.len)
561	{
562	memcpy (cur, v.ptr, v.len);
563	cur += v.len;
564	}
565	}
566
567	return *this;
568	}
569
570	packet &packet::operator <<(const data8 &v)
571	{
572	unsigned int len = min (v.len, 0x00FF);
573	return *this << uint8 (len) << data (v.ptr, len);
574	}
575
576	packet &packet::operator <<(const data16 &v)
577	{
578	unsigned int len = min (v.len, 0xFFFF);
579	return *this << uint16 (len) << data (v.ptr, len);
580	}
581
582	packet &packet::operator <<(const char *v)
583	{
584	return *this << data (v, strlen (v ? v : 0));
585	}
586
587	void
588	packet::vprintf (const char *format, va_list ap)
589	{
590	int size = room ();
591
592	int len = vsnprintf ((char *)cur, size, format, ap);
593
594	if (len >= size)
595	return reset ();
596
597	cur += len;
598	}
599