server/socket/lowlevel.C

/*
 * This file is part of Crossfire TRT, the Roguelike Realtime MORPG.
 * 
 * Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
 * Copyright (©) 1992,2007 Frank Tore Johansen
 * 
 * Crossfire TRT is free software: you can redistribute it and/or modify
 * it under the terms of the 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 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 <crossfire@schmorp.de>
 */

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 map1/map1a seem to be the only
          // nop'able commands and they are quite small.
          packet sl (mapmode == Map1Cmd ? "map1" : "map1a");
          send_packet (sl);
        }
      else
        return;
    }

  if (socket_ev.poll () & PE_W)
    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 () | PE_W);
          socket_ev.start ();
          return;
        }
      else
        {
          LOG (llevError, "socket write failed: %s\n", strerror (errno));
          destroy ();
          return;
        }
    }

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

/******************************************************************************
 *
 * 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 |

/**
 * 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+
  {"mapredraw",   PC(MapRedrawCmd) 0 },
  {"mapinfo",     PC(MapInfoCmd)   0 }, // CF+

  {"reply",       SC(ReplyCmd)     0 },
  {"exti",        SC(ExtiCmd)      0 }, // CF+
  {"addme",       SC(AddMeCmd)     0 },
  {"askface",     SC(AskFaceCmd)   0 },
  {"requestinfo", SC(RequestInfo)  0 },
  {"setfacemode", SC(SetFaceMode)  0 },
  {"setsound",    SC(SetSound)     0 },
  {"setup",       SC(SetUp)        0 },
  {"version",     SC(VersionCmd)   0 },
  {"toggleextendedinfos", SC(ToggleExtendedInfos) 0 }, /*Added: tchize */
  {"toggleextendedtext",  SC(ToggleExtendedText)  0 },   /*Added: tchize */
  {"asksmooth",   SC(AskSmooth)    0 },     /*Added: tchize (smoothing technologies) */
};

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 && !strncmp (data, "say " , 4))
    return true;
  if (len > 5 && !strncmp (data, "chat ", 5))
    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);
      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;
    }

  inbuf [pkt_len] = 0;      /* 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 + (sizeof (packets) / sizeof (packets[0])); ++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:
  skip_packet (pkt_len);

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

  return true;
}

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

  if (got & PE_W)
    {
      write_outputbuffer ();

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

  if (got & PE_R)
    {
      //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 () & ~PE_R);
          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;

          cmd_ev.start ();
        }
    }
}

// called whenever we have additional commands to process
void
client::cmd_cb (iw &w)
{
  if (handle_packet ())
    w.start ();
  else
    flush ();
}

/*******************************************************************************
 *
 * 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);
}

// returns true when the message needs special (read: perl) treatment
static bool
msg_is_special (const char *msg)
{   
  return msg [strcspn (msg, "<[&\n")];
}

void
client::send_msg (int color, const char *type, const char *msg)
{
  if (msg_is_special (msg))
    cfperl_send_msg (this, color, type, msg);
  else if (can_msg)
    send_packet_printf ("msg %d %s %s", color & NDI_CLIENT_MASK, type, msg);
  else if (color < 0)
    return; // client cannot handle this
  else
    send_packet_printf ("drawinfo %d %s", color & NDI_COLOR_MASK, 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:	1.56
Committed:	Mon Jul 30 02:03:03 2007 UTC (16 years, 9 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.55:	+0 -38 lines
Log Message:	big semantic change - old server and crossfire did update/draw maps check for player commands, move players and monsters flush sockets - new server does check for player commands, move players and monsters update/draw maps flush sockets I have zero idea why the old code didn't do it this way. the net effect is that there is a guarenteed delay of one tick between an issued command and the player seeing its execution. The same for monster movements. That is, the new ordering reduces "lag" by a constant 120ms, which is immense, and can be felt immediately. This is a change I wanted to do for a long time. Apart from that, the tcp send code has been simplified and underwent some further tuning, leading to an even more accurate congestion management.
#	Content
1	/*
2	* This file is part of Crossfire TRT, the Roguelike Realtime MORPG.
3	*
4	* Copyright (©) 2005,2006,2007 Marc Alexander Lehmann / Robin Redeker / the Crossfire TRT team
5	* Copyright (©) 1992,2007 Frank Tore Johansen
6	*
7	* Crossfire TRT is free software: you can redistribute it and/or modify
8	* it under the terms of the GNU General Public License as published by
9	* the Free Software Foundation, either version 3 of the License, or
10	* (at your option) any later version.
11	*
12	* This program is distributed in the hope that it will be useful,
13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15	* GNU General Public License for more details.
16	*
17	* You should have received a copy of the GNU General Public License
18	* along with this program. If not, see <http://www.gnu.org/licenses/>.
19	*
20	* The authors can be reached via e-mail to <crossfire@schmorp.de>
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 map1/map1a seem to be the only
59	// nop'able commands and they are quite small.
60	packet sl (mapmode == Map1Cmd ? "map1" : "map1a");
61	send_packet (sl);
62	}
63	else
64	return;
65	}
66
67	if (socket_ev.poll () & PE_W)
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 () \| PE_W);
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 () & ~PE_W);
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	/**
163	* Dispatch table for the server.
164	*/
165	static struct packet_type packets[] = {
166	{"ncom", PC(NewPlayerCmd) PF_PLAYING \| PF_COMMAND6 },
167	{"command", PC(PlayerCmd) PF_PLAYING \| PF_COMMAND0 },
168
169	{"examine", PC(ExamineCmd) PF_PLAYING },
170	{"ex", PC(ExCmd) PF_PLAYING },
171	{"apply", PC(ApplyCmd) PF_PLAYING },
172	{"lookat", PC(LookAt) PF_PLAYING },
173	{"lock", PC(LockItem) PF_PLAYING },
174	{"mark", PC(MarkItem) PF_PLAYING },
175	{"move", PC(MoveCmd) PF_PLAYING },
176	{"ext", PC(ExtCmd) 0 }, // CF+
177	{"mapredraw", PC(MapRedrawCmd) 0 },
178	{"mapinfo", PC(MapInfoCmd) 0 }, // CF+
179
180	{"reply", SC(ReplyCmd) 0 },
181	{"exti", SC(ExtiCmd) 0 }, // CF+
182	{"addme", SC(AddMeCmd) 0 },
183	{"askface", SC(AskFaceCmd) 0 },
184	{"requestinfo", SC(RequestInfo) 0 },
185	{"setfacemode", SC(SetFaceMode) 0 },
186	{"setsound", SC(SetSound) 0 },
187	{"setup", SC(SetUp) 0 },
188	{"version", SC(VersionCmd) 0 },
189	{"toggleextendedinfos", SC(ToggleExtendedInfos) 0 }, /Added: tchize /
190	{"toggleextendedtext", SC(ToggleExtendedText) 0 }, /Added: tchize /
191	{"asksmooth", SC(AskSmooth) 0 }, /Added: tchize (smoothing technologies) /
192	};
193
194	bool
195	client::may_execute (const packet_type *pkt) const
196	{
197	return (!(pkt->flags & PF_PLAYER) \|\| pl)
198	&& (!(pkt->flags & PF_PLAYING) \|\| state == ST_PLAYING);
199	}
200
201	// HACK: some commands currently should be executed
202	// even when the player is frozen. this hack detects
203	// those commands. it should be folded into may_execute,
204	// but kept seperate to emphasise the hack aspect, i.e.
205	// do it better, then remove.
206	static bool
207	always_immediate (const client ns, const packet_type pkt, const char *data, int len)
208	{
209	if (!(pkt->flags & (PF_COMMAND0 \| PF_COMMAND6)))
210	return false;
211
212	if (!ns->pl \|\| !ns->pl->ob \|\| !ns->pl->ob->map)
213	return false;
214
215	if (pkt->flags & PF_COMMAND6)
216	{
217	data += 6;
218	len -= 6;
219	}
220
221	if (len > 4 && !strncmp (data, "say " , 4))
222	return true;
223	if (len > 5 && !strncmp (data, "chat ", 5))
224	return true;
225
226	return false;
227	}
228
229	void
230	client::execute (const packet_type pkt, char data, int datalen)
231	{
232	if (may_execute (pkt) \|\| always_immediate (this, pkt, data, datalen))
233	{
234	//TODO: only one format
235	if (pkt->flags & PF_PLAYER)
236	((void ()(char , int, player ))pkt->cb)((char )data, datalen, pl);
237	else
238	((void ()(char , int, client ))pkt->cb)((char )data, datalen, this);
239	}
240	else
241	send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED \| NDI_REPLY, pkt->name);
242	}
243
244	bool
245	client::handle_packet ()
246	{
247	int pkt_len = next_packet ();
248
249	if (!pkt_len)
250	return false;
251	else if (pkt_len < 0)
252	{
253	LOG (llevError, "read error on player %s\n",
254	pl && pl->ob ? &pl->ob->name : "[anonymous]");
255	destroy ();
256	return false;
257	}
258
259	inbuf [pkt_len] = 0; /* Terminate buffer - useful for string data */
260
261	/* First, break out beginning word. There are at least
262	* a few commands that do not have any paremeters. If
263	* we get such a command, don't worry about trying
264	* to break it up.
265	*/
266	int datalen;
267	char data = strchr ((char )inbuf + 2, ' ');
268
269	if (data)
270	{
271	*data++ = 0;
272	datalen = pkt_len - (data - (char *)inbuf);
273	}
274	else
275	{
276	data = (char *)inbuf + 2; // better read garbage than segfault
277	datalen = 0;
278	}
279
280	for (packet_type *pkt = packets; pkt < packets + (sizeof (packets) / sizeof (packets[0])); ++pkt)
281	if (!strcmp ((char *)inbuf + 2, pkt->name))
282	{
283	if (pkt->flags & PF_PLAYER && !always_immediate (this, pkt, data, datalen))
284	queue_command (pkt, data, datalen);
285	else
286	execute (pkt, data, datalen);
287
288	goto next_packet;
289	}
290
291	// If we get here, we didn't find a valid command.
292	send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED \| NDI_REPLY, (char *)inbuf + 2);
293	next_packet:
294	skip_packet (pkt_len);
295
296	// input buffer has space again
297	socket_ev.poll (socket_ev.poll () \| PE_R);
298
299	return true;
300	}
301
302	// callback called when socket is either readable or writable
303	void
304	client::socket_cb (iow &w, int got)
305	{
306	//TODO remove when we have better socket cleanup logic
307	if (destroyed ())
308	{
309	socket_ev.poll (0);
310	return;
311	}
312
313	if (got & PE_W)
314	{
315	write_outputbuffer ();
316
317	if (!outputbuffer.len)
318	socket_ev.poll (socket_ev.poll () & ~PE_W);
319	}
320
321	if (got & PE_R)
322	{
323	//TODO: rate-limit tcp connection in better ways, important
324
325	int amount = sizeof (inbuf) - inbuf_len;
326
327	if (!amount)
328	{
329	// input buffer full
330	socket_ev.poll (socket_ev.poll () & ~PE_R);
331	return;
332	}
333
334	amount = read (fd, inbuf + inbuf_len, amount);
335
336	if (!amount)
337	{
338	destroy ();
339	return;
340	}
341	else if (amount < 0)
342	{
343	if (errno != EAGAIN && errno != EINTR)
344	{
345	LOG (llevError, "read error: %s\n", strerror (errno));
346	destroy ();
347	return;
348	}
349
350	// should not be here, normally
351	}
352	else
353	{
354	inbuf_len += amount;
355
356	cmd_ev.start ();
357	}
358	}
359	}
360
361	// called whenever we have additional commands to process
362	void
363	client::cmd_cb (iw &w)
364	{
365	if (handle_packet ())
366	w.start ();
367	else
368	flush ();
369	}
370
371	/*******************************************************************************
372	*
373	* Start of write related routines.
374	*
375	******************************************************************************/
376
377	/**
378	* Adds data to a socket buffer for whatever reason.
379	*
380	* ns is the socket we are adding the data to, buf is the start of the
381	* data, and len is the number of bytes to add.
382	*/
383	void
384	client::send (void *buf_, int len)
385	{
386	char buf = (char )buf_;
387
388	if (destroyed () \|\| !buf)
389	return;
390
391	if (len + outputbuffer.len > SOCKETBUFSIZE)
392	{
393	LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
394	// shutdown the socket, this is safer than destroying it immediately
395	// as lots of code in the callchain might still access the map etc.
396	shutdown (fd, SHUT_RDWR);
397	return;
398	}
399
400	int avail, end;
401
402	/* data + end is where we start putting the new data. The last byte
403	* currently in use is actually data + end -1
404	*/
405	end = outputbuffer.start + outputbuffer.len;
406	/* The buffer is already in a wrapped state, so adjust end */
407	if (end >= SOCKETBUFSIZE)
408	end -= SOCKETBUFSIZE;
409
410	avail = SOCKETBUFSIZE - end;
411
412	/* We can all fit it behind the current data without wrapping */
413	if (avail >= len)
414	memcpy (outputbuffer.data + end, buf, len);
415	else
416	{
417	memcpy (outputbuffer.data + end, buf, avail);
418	memcpy (outputbuffer.data, buf + avail, len - avail);
419	}
420
421	outputbuffer.len += len;
422	}
423
424	/**
425	* Takes a string of data, and writes it out to the socket. A very handy
426	* shortcut function.
427	*/
428	void
429	client::send_packet (packet &sl)
430	{
431	if (destroyed ())
432	return;
433
434	if (sl.length () > MAXSOCKBUF)
435	{
436	LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
437	/* Almost certainly we've overflowed a buffer, so quit now to make
438	* it easier to debug.
439	*/
440	abort ();
441	}
442
443	if (!sl.length ())
444	return;
445
446	assert (sl.hdrlen == 2);
447
448	sl.buf_ [0] = sl.length () >> 8;
449	sl.buf_ [1] = sl.length () ;
450
451	send (sl.buf_, sl.length () + sl.hdrlen);
452	}
453
454	void
455	client::send_packet (const char *buf, int len)
456	{
457	packet sl;
458
459	sl << data (buf, len);
460	send_packet (sl);
461	}
462
463	void
464	client::send_packet (const char *buf)
465	{
466	send_packet (buf, strlen (buf));
467	}
468
469	void
470	client::send_packet_printf (const char *format, ...)
471	{
472	packet sl;
473
474	va_list ap;
475	va_start (ap, format);
476	sl.vprintf (format, ap);
477	va_end (ap);
478
479	send_packet (sl);
480	}
481
482	// returns true when the message needs special (read: perl) treatment
483	static bool
484	msg_is_special (const char *msg)
485	{
486	return msg [strcspn (msg, "<[&\n")];
487	}
488
489	void
490	client::send_msg (int color, const char type, const char msg)
491	{
492	if (msg_is_special (msg))
493	cfperl_send_msg (this, color, type, msg);
494	else if (can_msg)
495	send_packet_printf ("msg %d %s %s", color & NDI_CLIENT_MASK, type, msg);
496	else if (color < 0)
497	return; // client cannot handle this
498	else
499	send_packet_printf ("drawinfo %d %s", color & NDI_COLOR_MASK, msg);
500	}
501
502	void
503	client::send_drawinfo (const char *msg, int flags)
504	{
505	send_msg (flags, "log", msg);
506	}
507
508	/***********************************************************************
509	*
510	* packet functions/utilities
511	*
512	**********************************************************************/
513
514	packet::packet (const char *name)
515	{
516	reset ();
517
518	int len = strlen (name);
519	memcpy (cur, name, len); cur += len;
520	*cur++ = ' ';
521	}
522
523	packet &packet::operator <<(const ber32 v)
524	{
525	enum { maxlen = 32 / 7 + 1};
526	uint8 buf[maxlen];
527	uint8 *p = buf + maxlen;
528	uint32 val = v.val;
529
530	*--p = val & 0x7F;
531
532	while (val > 0x7F)
533	{
534	val >>= 7;
535	*--p = (val & 0x7F) \| 0x80;
536	}
537
538	return *this << data (p, buf + maxlen - p);
539	}
540
541	packet &packet::operator <<(const data &v)
542	{
543	if (room () < v.len)
544	reset ();
545	else
546	{
547	if (v.len)
548	{
549	memcpy (cur, v.ptr, v.len);
550	cur += v.len;
551	}
552	}
553
554	return *this;
555	}
556
557	packet &packet::operator <<(const data8 &v)
558	{
559	unsigned int len = min (v.len, 0x00FF);
560	return *this << uint8 (len) << data (v.ptr, len);
561	}
562
563	packet &packet::operator <<(const data16 &v)
564	{
565	unsigned int len = min (v.len, 0xFFFF);
566	return *this << uint16 (len) << data (v.ptr, len);
567	}
568
569	packet &packet::operator <<(const char *v)
570	{
571	return *this << data (v, strlen (v ? v : 0));
572	}
573
574	void
575	packet::vprintf (const char *format, va_list ap)
576	{
577	int size = room ();
578
579	int len = vsnprintf ((char *)cur, size, format, ap);
580
581	if (len >= size)
582	return reset ();
583
584	cur += len;
585	}
586