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 | 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, 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, (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_;

  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_drawinfo (const char *msg, int flags)
{
  send_packet_printf ("drawinfo %d %s", flags, 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;
}

/******************************************************************************
 *
 * 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:	1.39
Committed:	Mon Apr 23 19:10:17 2007 UTC (17 years, 1 month ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.38:	+5 -4 lines
Log Message:	implement ex command support to quickly retrieve item descriptions
#	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 \| PF_COMMAND6 },
192	{"command", PC(PlayerCmd) PF_PLAYING \| PF_COMMAND0 },
193
194	{"examine", PC(ExamineCmd) PF_PLAYING },
195	{"ex", PC(ExCmd) PF_PLAYING },
196	{"apply", PC(ApplyCmd) PF_PLAYING },
197	{"lookat", PC(LookAt) PF_PLAYING },
198	{"lock", PC(LockItem) PF_PLAYING },
199	{"mark", PC(MarkItem) PF_PLAYING },
200	{"move", PC(MoveCmd) PF_PLAYING },
201	{"ext", PC(ExtCmd) 0 }, // CF+
202	{"mapredraw", PC(MapRedrawCmd) 0 },
203	{"mapinfo", PC(MapInfoCmd) 0 }, // CF+
204
205	{"reply", SC(ReplyCmd) 0 },
206	{"exti", SC(ExtiCmd) 0 }, // CF+
207	{"addme", SC(AddMeCmd) 0 },
208	{"askface", SC(AskFaceCmd) 0 },
209	{"requestinfo", SC(RequestInfo) 0 },
210	{"setfacemode", SC(SetFaceMode) 0 },
211	{"setsound", SC(SetSound) 0 },
212	{"setup", SC(SetUp) 0 },
213	{"version", SC(VersionCmd) 0 },
214	{"toggleextendedinfos", SC(ToggleExtendedInfos) 0 }, /Added: tchize /
215	{"toggleextendedtext", SC(ToggleExtendedText) 0 }, /Added: tchize /
216	{"asksmooth", SC(AskSmooth) 0 }, /Added: tchize (smoothing technologies) /
217	};
218
219	bool
220	client::may_execute (const packet_type *pkt) const
221	{
222	return (!(pkt->flags & PF_PLAYER) \|\| pl)
223	&& (!(pkt->flags & PF_PLAYING) \|\| state == ST_PLAYING);
224	}
225
226	// HACK: some commands currently should be executed
227	// even when the player is frozen. this hack detects
228	// those commands. it should be folded into may_execute,
229	// but kept seperate to emphasise the hack aspect, i.e.
230	// do it better, then remove.
231	static bool
232	always_immediate (const client ns, const packet_type pkt, const char *data, int len)
233	{
234	if (!(pkt->flags & (PF_COMMAND0 \| PF_COMMAND6)))
235	return false;
236
237	if (!ns->pl \|\| !ns->pl->ob \|\| !ns->pl->ob->map)
238	return false;
239
240	if (pkt->flags & PF_COMMAND6)
241	{
242	data += 6;
243	len -= 6;
244	}
245
246	if (len > 4 && !strncmp (data, "say " , 4))
247	return true;
248	if (len > 5 && !strncmp (data, "chat ", 5))
249	return true;
250
251	return false;
252	}
253
254	void
255	client::execute (const packet_type pkt, char data, int datalen)
256	{
257	if (may_execute (pkt) \|\| always_immediate (this, pkt, data, datalen))
258	{
259	//TODO: only one format
260	if (pkt->flags & PF_PLAYER)
261	((void ()(char , int, player ))pkt->cb)((char )data, datalen, pl);
262	else
263	((void ()(char , int, client ))pkt->cb)((char )data, datalen, this);
264	}
265	else
266	send_packet_printf ("drawinfo %d ERROR: you cannot execute '%s' now.", NDI_RED, pkt->name);
267	}
268
269	bool
270	client::handle_packet ()
271	{
272	int pkt_len = next_packet ();
273
274	if (!pkt_len)
275	return false;
276	else if (pkt_len < 0)
277	{
278	LOG (llevError, "read error on player %s\n",
279	pl && pl->ob ? &pl->ob->name : "[anonymous]");
280	destroy ();
281	return false;
282	}
283
284	inbuf [pkt_len] = 0; /* Terminate buffer - useful for string data */
285
286	/* First, break out beginning word. There are at least
287	* a few commands that do not have any paremeters. If
288	* we get such a command, don't worry about trying
289	* to break it up.
290	*/
291	int datalen;
292	char data = strchr ((char )inbuf + 2, ' ');
293
294	if (data)
295	{
296	*data++ = 0;
297	datalen = pkt_len - (data - (char *)inbuf);
298	}
299	else
300	{
301	data = (char *)inbuf + 2; // better read garbage than segfault
302	datalen = 0;
303	}
304
305	for (packet_type *pkt = packets; pkt < packets + (sizeof (packets) / sizeof (packets[0])); ++pkt)
306	if (!strcmp ((char *)inbuf + 2, pkt->name))
307	{
308	if (pkt->flags & PF_PLAYER && !always_immediate (this, pkt, data, datalen))
309	queue_command (pkt, data, datalen);
310	else
311	execute (pkt, data, datalen);
312
313	goto next_packet;
314	}
315
316	// If we get here, we didn't find a valid command.
317	send_packet_printf ("drawinfo %d ERROR: command '%s' not supported.", NDI_RED, (char *)inbuf + 2);
318	next_packet:
319	skip_packet (pkt_len);
320
321	// input buffer has space again
322	socket_ev.poll (socket_ev.poll () \| PE_R);
323
324	return true;
325	}
326
327	// callback called when socket is either readable or writable
328	void
329	client::socket_cb (iow &w, int got)
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 (got & PE_W)
339	{
340	write_outputbuffer ();
341
342	if (!outputbuffer.len)
343	socket_ev.poll (socket_ev.poll () & ~PE_W);
344	}
345
346	if (got & PE_R)
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 () & ~PE_R);
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
381	cst_tot.ibytes += amount;
382	cst_lst.ibytes += amount;
383
384	cmd_ev.start ();
385	}
386	}
387	}
388
389	// called whenever we have additional commands to process
390	void
391	client::cmd_cb (iw &w)
392	{
393	if (handle_packet ())
394	w.start ();
395	else
396	flush ();
397	}
398
399	/*******************************************************************************
400	*
401	* Start of write related routines.
402	*
403	******************************************************************************/
404
405	/**
406	* Adds data to a socket buffer for whatever reason.
407	*
408	* ns is the socket we are adding the data to, buf is the start of the
409	* data, and len is the number of bytes to add.
410	*/
411	void
412	client::send (void *buf_, int len)
413	{
414	char buf = (char )buf_;
415
416	if (destroyed () \|\| !buf)
417	return;
418
419	if (len + outputbuffer.len > SOCKETBUFSIZE)
420	{
421	LOG (llevDebug, "socket on fd %d has overrun internal buffer - marking as dead\n", fd);
422	// shutdown the socket, this is safer than destroying it immediately
423	// as lots of code in the callchain might still access the map etc.
424	shutdown (fd, SHUT_RDWR);
425	return;
426	}
427
428	int avail, end;
429
430	/* data + end is where we start putting the new data. The last byte
431	* currently in use is actually data + end -1
432	*/
433	end = outputbuffer.start + outputbuffer.len;
434	/* The buffer is already in a wrapped state, so adjust end */
435	if (end >= SOCKETBUFSIZE)
436	end -= SOCKETBUFSIZE;
437
438	avail = SOCKETBUFSIZE - end;
439
440	/* We can all fit it behind the current data without wrapping */
441	if (avail >= len)
442	memcpy (outputbuffer.data + end, buf, len);
443	else
444	{
445	memcpy (outputbuffer.data + end, buf, avail);
446	memcpy (outputbuffer.data, buf + avail, len - avail);
447	}
448
449	outputbuffer.len += len;
450	}
451
452	/**
453	* Takes a string of data, and writes it out to the socket. A very handy
454	* shortcut function.
455	*/
456	void
457	client::send_packet (packet &sl)
458	{
459	if (destroyed ())
460	return;
461
462	if (sl.length () >= MAXSOCKBUF)
463	{
464	LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", sl.length ());
465	/* Almost certainly we've overflowed a buffer, so quit now to make
466	* it easier to debug.
467	*/
468	abort ();
469	}
470
471	if (!sl.length ())
472	return;
473
474	assert (sl.hdrlen == 2);
475
476	sl.buf_ [0] = sl.length () >> 8;
477	sl.buf_ [1] = sl.length () ;
478
479	send (sl.buf_, sl.length () + sl.hdrlen);
480	}
481
482	void
483	client::send_packet (const char *buf, int len)
484	{
485	packet sl;
486
487	sl << data (buf, len);
488	send_packet (sl);
489	}
490
491	void
492	client::send_packet (const char *buf)
493	{
494	send_packet (buf, strlen (buf));
495	}
496
497	void
498	client::send_packet_printf (const char *format, ...)
499	{
500	packet sl;
501
502	va_list ap;
503	va_start (ap, format);
504	sl.vprintf (format, ap);
505	va_end (ap);
506
507	send_packet (sl);
508	}
509
510	void
511	client::send_drawinfo (const char *msg, int flags)
512	{
513	send_packet_printf ("drawinfo %d %s", flags, msg);
514	}
515
516	/***********************************************************************
517	*
518	* packet functions/utilities
519	*
520	**********************************************************************/
521
522	packet::packet (const char *name)
523	{
524	reset ();
525
526	int len = strlen (name);
527	memcpy (cur, name, len); cur += len;
528	*cur++ = ' ';
529	}
530
531	packet &packet::operator <<(const ber32 v)
532	{
533	enum { maxlen = 32 / 7 + 1};
534	uint8 buf[maxlen];
535	uint8 *p = buf + maxlen;
536	uint32 val = v.val;
537
538	*--p = val & 0x7F;
539
540	while (val > 0x7F)
541	{
542	val >>= 7;
543	*--p = (val & 0x7F) \| 0x80;
544	}
545
546	return *this << data (p, buf + maxlen - p);
547	}
548
549	packet &packet::operator <<(const data &v)
550	{
551	if (room () < v.len)
552	reset ();
553	else
554	{
555	if (v.len)
556	{
557	memcpy (cur, v.ptr, v.len);
558	cur += v.len;
559	}
560	}
561
562	return *this;
563	}
564
565	packet &packet::operator <<(const data8 &v)
566	{
567	unsigned int len = min (v.len, 0x00FF);
568	return *this << uint8 (len) << data (v.ptr, len);
569	}
570
571	packet &packet::operator <<(const data16 &v)
572	{
573	unsigned int len = min (v.len, 0xFFFF);
574	return *this << uint16 (len) << data (v.ptr, len);
575	}
576
577	packet &packet::operator <<(const char *v)
578	{
579	return *this << data (v, strlen (v ? v : 0));
580	}
581
582	void
583	packet::vprintf (const char *format, va_list ap)
584	{
585	int size = room ();
586
587	int len = vsnprintf ((char *)cur, size, format, ap);
588
589	if (len >= size)
590	return reset ();
591
592	cur += len;
593	}
594
595	/******************************************************************************
596	*
597	* statistics logging functions.
598	*
599	******************************************************************************/
600
601	#ifdef CS_LOGSTATS
602
603	/* cst_tot is for the life of the server, cst_last is for the last series of
604	* stats
605	*/
606	CS_Stats cst_tot, cst_lst;
607
608	/**
609	* Writes out the gathered stats. We clear cst_lst.
610	*/
611	void
612	write_cs_stats (void)
613	{
614	time_t now = time (NULL);
615
616	/* If no connections recently, don't both to log anything */
617	if (cst_lst.ibytes == 0 && cst_lst.obytes == 0)
618	return;
619
620	/* CSSTAT is put in so scripts can easily find the line */
621	LOG (llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
622	ctime (&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
623	now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes, cst_lst.max_conn, now - cst_lst.time_start);
624	cst_lst.ibytes = 0;
625	cst_lst.obytes = 0;
626	cst_lst.time_start = now;
627	}
628	#endif
629