server/socket/lowlevel.C

/*
 * CrossFire, A Multiplayer game for X-windows
 * 
 * Copyright (C) 2005, 2006, 2007 Marc Lehmann & Crossfire+ Development Team
 * Copyright (C) 1992 Frank Tore Johansen
 *
 * This program 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 2 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, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 * 
 * The author can be reached via e-mail to mark@pyramid.com
 */
 
/**
 * \file
 * Low-level socket-related functions.
 *
 * \date 2003-12-02
 *
 * Contains some base functions that both the client and server
 * can use.  As such, depending what we are being compiled for will
 * determine what we can include.  the client is designed have
 * CFCLIENT defined as part of its compile flags.
 */

using namespace std;

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

#ifdef __linux__
# include <sys/types.h>
# include <sys/socket.h>
# include <netinet/in.h>
# include <netinet/tcp.h>
#endif

// use a really low timeout, as it doesn't cost any bandwidth, and you can
// easily die in 20 seconds...
#define SOCKET_TIMEOUT1 10 * 1000
#define SOCKET_TIMEOUT2 20 * 1000

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

#ifdef __linux__
  // check time of last ack, and, if too old, kill connection
  struct tcp_info tcpi;
  socklen_t len = sizeof (tcpi);

  if (!getsockopt (fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
    {
      unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;

      rtt    = tcpi.tcpi_rtt;
      rttvar = tcpi.tcpi_rttvar;

      if (tcpi.tcpi_unacked && SOCKET_TIMEOUT1 < diff && diff < 0x80000000UL   // ack delayed for 20s
          && SOCKET_TIMEOUT2 < tcpi.tcpi_last_data_sent)       // no data sent for 10s
        {
          LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", fd,
               (unsigned) tcpi.tcpi_last_ack_recv, (unsigned) tcpi.tcpi_last_data_sent, (unsigned) tcpi.tcpi_unacked);
          destroy ();
        }
    }
#endif

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

  if (!outputbuffer.len || socket_ev.poll () & PE_W)
    return;

  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;
#ifdef CS_LOGSTATS
          cst_tot.obytes += res;
          cst_lst.obytes += res;
#endif
        }
      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);
          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 },
  {"command",     PC(PlayerCmd)    PF_PLAYING },

  {"examine",     PC(ExamineCmd)   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 },       /* Added: phil */
  {"mapinfo",     PC(MapInfoCmd)   0 },   /* CF+ */

  {"reply",       SC(ReplyCmd)     0 },
  {"exti",        SC(ExtiCmd)      0 }, /* CF+ */
  {"addme",       SC(AddMeCmd)     0 },
  {"askface",     SC(SendFaceCmd)  0 },     /* Added: phil */
  {"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);
}

void
client::execute (const packet_type *pkt, char *data, int datalen)
{
  if (may_execute (pkt))
    {
      //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, 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)
          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, (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;

          cst_tot.ibytes += amount;
          cst_lst.ibytes += 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_;
  char *pos = buf;
  int amt = 0;

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

  if (len + outputbuffer.len > SOCKETBUFSIZE)
    {
      LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
      destroy ();
      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);
}

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

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

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

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;
}

/******************************************************************************
 *
 * statistics logging functions.
 *
 ******************************************************************************/

#ifdef CS_LOGSTATS

/* cst_tot is for the life of the server, cst_last is for the last series of
 * stats
 */
CS_Stats cst_tot, cst_lst;

/**
 * Writes out the gathered stats.  We clear cst_lst.
 */
void
write_cs_stats (void)
{
  time_t now = time (NULL);

  /* If no connections recently, don't both to log anything */
  if (cst_lst.ibytes == 0 && cst_lst.obytes == 0)
    return;

  /* CSSTAT is put in so scripts can easily find the line */
  LOG (llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
       ctime (&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
       now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes, cst_lst.max_conn, now - cst_lst.time_start);
  cst_lst.ibytes = 0;
  cst_lst.obytes = 0;
  cst_lst.time_start = now;
}
#endif

Revision:	1.32
Committed:	Sat Jan 20 13:47:17 2007 UTC (17 years, 4 months ago) by pippijn
Content type:	text/plain
Branch:	MAIN
Changes since 1.31:	+22 -22 lines
Log Message:	comments
#	Content
1	/*
2	* CrossFire, A Multiplayer game for X-windows
3	*
4	* Copyright (C) 2005, 2006, 2007 Marc Lehmann & Crossfire+ Development Team
5	* Copyright (C) 1992 Frank Tore Johansen
6	*
7	* This program 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 2 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, write to the Free Software
19	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20	*
21	* The author can be reached via e-mail to mark@pyramid.com
22	*/
23
24	/**
25	* \file
26	* Low-level socket-related functions.
27	*
28	* \date 2003-12-02
29	*
30	* Contains some base functions that both the client and server
31	* can use. As such, depending what we are being compiled for will
32	* determine what we can include. the client is designed have
33	* CFCLIENT defined as part of its compile flags.
34	*/
35
36	using namespace std;
37
38	#include <global.h>
39	#include <sproto.h>
40	#include <cstdarg>
41
42	#ifdef __linux__
43	# include <sys/types.h>
44	# include <sys/socket.h>
45	# include <netinet/in.h>
46	# include <netinet/tcp.h>
47	#endif
48
49	// use a really low timeout, as it doesn't cost any bandwidth, and you can
50	// easily die in 20 seconds...
51	#define SOCKET_TIMEOUT1 10 * 1000
52	#define SOCKET_TIMEOUT2 20 * 1000
53
54	void
55	client::flush ()
56	{
57	if (destroyed ())
58	return;
59
60	#ifdef __linux__
61	// check time of last ack, and, if too old, kill connection
62	struct tcp_info tcpi;
63	socklen_t len = sizeof (tcpi);
64
65	if (!getsockopt (fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
66	{
67	unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;
68
69	rtt = tcpi.tcpi_rtt;
70	rttvar = tcpi.tcpi_rttvar;
71
72	if (tcpi.tcpi_unacked && SOCKET_TIMEOUT1 < diff && diff < 0x80000000UL // ack delayed for 20s
73	&& SOCKET_TIMEOUT2 < tcpi.tcpi_last_data_sent) // no data sent for 10s
74	{
75	LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", fd,
76	(unsigned) tcpi.tcpi_last_ack_recv, (unsigned) tcpi.tcpi_last_data_sent, (unsigned) tcpi.tcpi_unacked);
77	destroy ();
78	}
79	}
80	#endif
81
82	/**
83	* Writes data to socket.
84	*
85	* When the socket is clear to write, and we have backlogged data, this
86	* is called to write it out.
87	*/
88
89	if (!outputbuffer.len \|\| socket_ev.poll () & PE_W)
90	return;
91
92	write_outputbuffer ();
93	}
94
95	void
96	client::write_outputbuffer ()
97	{
98	while (outputbuffer.len)
99	{
100	int res = write (fd, outputbuffer.data + outputbuffer.start,
101	min (outputbuffer.len, SOCKETBUFSIZE - outputbuffer.start));
102
103	if (res > 0)
104	{
105	outputbuffer.start += res;
106	/* wrap back to start of buffer */
107	if (outputbuffer.start == SOCKETBUFSIZE)
108	outputbuffer.start = 0;
109
110	outputbuffer.len -= res;
111	#ifdef CS_LOGSTATS
112	cst_tot.obytes += res;
113	cst_lst.obytes += res;
114	#endif
115	}
116	else if (res == 0)
117	{
118	LOG (llevError, "socket write failed, connection closed.\n");
119	destroy ();
120	return;
121	}
122	else if (errno == EINTR)
123	{
124	// just retry
125	}
126	else if (errno == EAGAIN)
127	{
128	// delay till ready
129	socket_ev.poll (socket_ev.poll () \| PE_W);
130	socket_ev.start ();
131	return;
132	}
133	else
134	{
135	LOG (llevError, "socket write failed: %s\n", strerror (errno));
136	destroy ();
137	return;
138	}
139	}
140
141	socket_ev.poll (socket_ev.poll () & ~PE_W);
142	}
143
144	/******************************************************************************
145	*
146	* Start of read routines.
147	*
148	******************************************************************************/
149
150	int
151	client::next_packet ()
152	{
153	if (inbuf_len >= 2)
154	{
155	int pkt_len = (inbuf [0] << 8) \| inbuf [1];
156
157	if (inbuf_len >= 2 + pkt_len)
158	return 2 + pkt_len;
159
160	if (inbuf_len == sizeof (inbuf))
161	{
162	send_packet_printf ("drawinfo %d input buffer overflow - closing connection.", NDI_RED);
163	destroy ();
164	return -1;
165	}
166	}
167
168	return 0;
169	}
170
171	void
172	client::skip_packet (int len)
173	{
174	inbuf_len -= len;
175	memmove (inbuf, inbuf + len, inbuf_len);
176	}
177
178	/*****************************************************************************
179	* Start of command dispatch area.
180	* The commands here are protocol commands.
181	****************************************************************************/
182
183	// SocketCommand, PlayingCommand, should not exist with those ugly casts
184	#define SC(cb) (void )static_cast<void ()(char , int, client )>(cb),
185	#define PC(cb) (void )static_cast<void ()(char , int, player )>(cb), PF_PLAYER \|
186
187	/**
188	* Dispatch table for the server.
189	*/
190	static struct packet_type packets[] = {
191	{"ncom", PC(NewPlayerCmd) PF_PLAYING },
192	{"command", PC(PlayerCmd) PF_PLAYING },
193
194	{"examine", PC(ExamineCmd) PF_PLAYING },
195	{"apply", PC(ApplyCmd) PF_PLAYING },
196	{"lookat", PC(LookAt) PF_PLAYING },
197	{"lock", PC(LockItem) PF_PLAYING },
198	{"mark", PC(MarkItem) PF_PLAYING },
199	{"move", PC(MoveCmd) PF_PLAYING },
200	{"ext", PC(ExtCmd) 0 }, /* CF+ */
201	{"mapredraw", PC(MapRedrawCmd) 0 }, /* Added: phil */
202	{"mapinfo", PC(MapInfoCmd) 0 }, /* CF+ */
203
204	{"reply", SC(ReplyCmd) 0 },
205	{"exti", SC(ExtiCmd) 0 }, /* CF+ */
206	{"addme", SC(AddMeCmd) 0 },
207	{"askface", SC(SendFaceCmd) 0 }, /* Added: phil */
208	{"requestinfo", SC(RequestInfo) 0 },
209	{"setfacemode", SC(SetFaceMode) 0 },
210	{"setsound", SC(SetSound) 0 },
211	{"setup", SC(SetUp) 0 },
212	{"version", SC(VersionCmd) 0 },
213	{"toggleextendedinfos", SC(ToggleExtendedInfos) 0 }, /Added: tchize /
214	{"toggleextendedtext", SC(ToggleExtendedText) 0 }, /Added: tchize /
215	{"asksmooth", SC(AskSmooth) 0 }, /Added: tchize (smoothing technologies) /
216	};
217
218	bool
219	client::may_execute (const packet_type *pkt) const
220	{
221	return (!(pkt->flags & PF_PLAYER) \|\| pl)
222	&& (!(pkt->flags & PF_PLAYING) \|\| state == ST_PLAYING);
223	}
224
225	void
226	client::execute (const packet_type pkt, char data, int datalen)
227	{
228	if (may_execute (pkt))
229	{
230	//TODO: only one format
231	if (pkt->flags & PF_PLAYER)
232	((void ()(char , int, player ))pkt->cb)((char )data, datalen, pl);
233	else
234	((void ()(char , int, client ))pkt->cb)((char )data, datalen, this);
235	}
236	else
237	send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED, pkt->name);
238	}
239
240	bool
241	client::handle_packet ()
242	{
243	int pkt_len = next_packet ();
244
245	if (!pkt_len)
246	return false;
247	else if (pkt_len < 0)
248	{
249	LOG (llevError, "read error on player %s\n",
250	pl && pl->ob ? &pl->ob->name : "[anonymous]");
251	destroy ();
252	return false;
253	}
254
255	inbuf [pkt_len] = 0; /* Terminate buffer - useful for string data */
256
257	/* First, break out beginning word. There are at least
258	* a few commands that do not have any paremeters. If
259	* we get such a command, don't worry about trying
260	* to break it up.
261	*/
262	int datalen;
263	char data = strchr ((char )inbuf + 2, ' ');
264
265	if (data)
266	{
267	*data++ = 0;
268	datalen = pkt_len - (data - (char *)inbuf);
269	}
270	else
271	{
272	data = (char *)inbuf + 2; // better read garbage than segfault
273	datalen = 0;
274	}
275
276	for (packet_type *pkt = packets; pkt < packets + (sizeof (packets) / sizeof (packets[0])); ++pkt)
277	if (!strcmp ((char *)inbuf + 2, pkt->name))
278	{
279	if (pkt->flags & PF_PLAYER)
280	queue_command (pkt, data, datalen);
281	else
282	execute (pkt, data, datalen);
283
284	goto next_packet;
285	}
286
287	// If we get here, we didn't find a valid command.
288	send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED, (char *)inbuf + 2);
289	next_packet:
290	skip_packet (pkt_len);
291
292	// input buffer has space again
293	socket_ev.poll (socket_ev.poll () \| PE_R);
294
295	return true;
296	}
297
298	// callback called when socket is either readable or writable
299	void
300	client::socket_cb (iow &w, int got)
301	{
302	//TODO remove when we have better socket cleanup logic
303	if (destroyed ())
304	{
305	socket_ev.poll (0);
306	return;
307	}
308
309	if (got & PE_W)
310	{
311	write_outputbuffer ();
312
313	if (!outputbuffer.len)
314	socket_ev.poll (socket_ev.poll () & ~PE_W);
315	}
316
317	if (got & PE_R)
318	{
319	//TODO: rate-limit tcp connection in better ways, important
320
321	int amount = sizeof (inbuf) - inbuf_len;
322
323	if (!amount)
324	{
325	// input buffer full
326	socket_ev.poll (socket_ev.poll () & ~PE_R);
327	return;
328	}
329
330	amount = read (fd, inbuf + inbuf_len, amount);
331
332	if (!amount)
333	{
334	destroy ();
335	return;
336	}
337	else if (amount < 0)
338	{
339	if (errno != EAGAIN && errno != EINTR)
340	{
341	LOG (llevError, "read error: %s\n", strerror (errno));
342	destroy ();
343	return;
344	}
345
346	// should not be here, normally
347	}
348	else
349	{
350	inbuf_len += amount;
351
352	cst_tot.ibytes += amount;
353	cst_lst.ibytes += amount;
354
355	cmd_ev.start ();
356	}
357	}
358	}
359
360	// called whenever we have additional commands to process
361	void
362	client::cmd_cb (iw &w)
363	{
364	if (handle_packet ())
365	w.start ();
366	else
367	flush ();
368	}
369
370	/*******************************************************************************
371	*
372	* Start of write related routines.
373	*
374	******************************************************************************/
375
376	/**
377	* Adds data to a socket buffer for whatever reason.
378	*
379	* ns is the socket we are adding the data to, buf is the start of the
380	* data, and len is the number of bytes to add.
381	*/
382	void
383	client::send (void *buf_, int len)
384	{
385	char buf = (char )buf_;
386	char *pos = buf;
387	int amt = 0;
388
389	if (destroyed () \|\| !buf)
390	return;
391
392	if (len + outputbuffer.len > SOCKETBUFSIZE)
393	{
394	LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
395	destroy ();
396	return;
397	}
398
399	int avail, end;
400
401	/* data + end is where we start putting the new data. The last byte
402	* currently in use is actually data + end -1
403	*/
404	end = outputbuffer.start + outputbuffer.len;
405	/* The buffer is already in a wrapped state, so adjust end */
406	if (end >= SOCKETBUFSIZE)
407	end -= SOCKETBUFSIZE;
408
409	avail = SOCKETBUFSIZE - end;
410
411	/* We can all fit it behind the current data without wrapping */
412	if (avail >= len)
413	memcpy (outputbuffer.data + end, buf, len);
414	else
415	{
416	memcpy (outputbuffer.data + end, buf, avail);
417	memcpy (outputbuffer.data, buf + avail, len - avail);
418	}
419
420	outputbuffer.len += len;
421	}
422
423	/**
424	* Takes a string of data, and writes it out to the socket. A very handy
425	* shortcut function.
426	*/
427	void
428	client::send_packet (packet &sl)
429	{
430	if (destroyed ())
431	return;
432
433	if (sl.length () >= MAXSOCKBUF)
434	{
435	LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
436	/* Almost certainly we've overflowed a buffer, so quit now to make
437	* it easier to debug.
438	*/
439	abort ();
440	}
441
442	if (!sl.length ())
443	return;
444
445	assert (sl.hdrlen == 2);
446
447	sl.buf_ [0] = sl.length () >> 8;
448	sl.buf_ [1] = sl.length () ;
449
450	send (sl.buf_, sl.length () + sl.hdrlen);
451	}
452
453	void
454	client::send_packet (const char *buf, int len)
455	{
456	packet sl;
457
458	sl << data (buf, len);
459	send_packet (sl);
460	}
461
462	void
463	client::send_packet (const char *buf)
464	{
465	send_packet (buf, strlen (buf));
466	}
467
468	void
469	client::send_packet_printf (const char *format, ...)
470	{
471	packet sl;
472
473	va_list ap;
474	va_start (ap, format);
475	sl.vprintf (format, ap);
476	va_end (ap);
477
478	send_packet (sl);
479	}
480
481	/***********************************************************************
482	*
483	* packet functions/utilities
484	*
485	**********************************************************************/
486
487	packet::packet (const char *name)
488	{
489	reset ();
490
491	int len = strlen (name);
492	memcpy (cur, name, len); cur += len;
493	*cur++ = ' ';
494	}
495
496	packet &packet::operator <<(const data &v)
497	{
498	if (room () < v.len)
499	reset ();
500	else
501	{
502	if (v.len)
503	{
504	memcpy (cur, v.ptr, v.len);
505	cur += v.len;
506	}
507	}
508
509	return *this;
510	}
511
512	packet &packet::operator <<(const data8 &v)
513	{
514	unsigned int len = min (v.len, 0x00FF);
515	return *this << uint8 (len) << data (v.ptr, len);
516	}
517
518	packet &packet::operator <<(const data16 &v)
519	{
520	unsigned int len = min (v.len, 0xFFFF);
521	return *this << uint16 (len) << data (v.ptr, len);
522	}
523
524	packet &packet::operator <<(const char *v)
525	{
526	return *this << data (v, strlen (v ? v : 0));
527	}
528
529	void
530	packet::vprintf (const char *format, va_list ap)
531	{
532	int size = room ();
533
534	int len = vsnprintf ((char *)cur, size, format, ap);
535
536	if (len >= size)
537	return reset ();
538
539	cur += len;
540	}
541
542	/******************************************************************************
543	*
544	* statistics logging functions.
545	*
546	******************************************************************************/
547
548	#ifdef CS_LOGSTATS
549
550	/* cst_tot is for the life of the server, cst_last is for the last series of
551	* stats
552	*/
553	CS_Stats cst_tot, cst_lst;
554
555	/**
556	* Writes out the gathered stats. We clear cst_lst.
557	*/
558	void
559	write_cs_stats (void)
560	{
561	time_t now = time (NULL);
562
563	/* If no connections recently, don't both to log anything */
564	if (cst_lst.ibytes == 0 && cst_lst.obytes == 0)
565	return;
566
567	/* CSSTAT is put in so scripts can easily find the line */
568	LOG (llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
569	ctime (&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
570	now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes, cst_lst.max_conn, now - cst_lst.time_start);
571	cst_lst.ibytes = 0;
572	cst_lst.obytes = 0;
573	cst_lst.time_start = now;
574	}
575	#endif
576