server/socket/lowlevel.C


/*
 * static char *rcsid_sockets_c =
 *    "$Id: lowlevel.C,v 1.4 2006-08-30 16:30:37 root Exp $";
 */

/*
    CrossFire, A Multiplayer game for X-windows

    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 <newclient.h>
#include <sproto.h>

#ifdef __linux__
# include <sys/types.h>
# include <sys/socket.h>
# include <netinet/in.h>
# define TCP_HZ 1000            // sorry...
# 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
#define SOCKET_TIMEOUT2 20

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

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

      if (tcpi.tcpi_unacked && SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL   // ack delayed for 20s
          && SOCKET_TIMEOUT2 * TCP_HZ < 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", ns->fd,
               (unsigned) tcpi.tcpi_last_ack_recv, (unsigned) tcpi.tcpi_last_data_sent, (unsigned) tcpi.tcpi_unacked);
          ns->status = Ns_Dead;
        }
    }

  int val;

  val = 0;
  setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
  val = 1;
  setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
#endif
}

/***********************************************************************
 *
 * SockList functions/utilities
 *
 **********************************************************************/

void
SockList_Init (SockList * sl)
{
  sl->len = 0;
  sl->buf = NULL;
}

void
SockList_AddInt (SockList * sl, uint32 data)
{
  sl->buf[sl->len++] = (data >> 24) & 0xff;
  sl->buf[sl->len++] = (data >> 16) & 0xff;
  sl->buf[sl->len++] = (data >> 8) & 0xff;
  sl->buf[sl->len++] = data & 0xff;
}

void
SockList_AddInt64 (SockList * sl, uint64 data)
{
  sl->buf[sl->len++] = (char) ((data >> 56) & 0xff);
  sl->buf[sl->len++] = (char) ((data >> 48) & 0xff);
  sl->buf[sl->len++] = (char) ((data >> 40) & 0xff);
  sl->buf[sl->len++] = (char) ((data >> 32) & 0xff);

  sl->buf[sl->len++] = (char) ((data >> 24) & 0xff);
  sl->buf[sl->len++] = (char) ((data >> 16) & 0xff);
  sl->buf[sl->len++] = (char) ((data >> 8) & 0xff);
  sl->buf[sl->len++] = (char) (data & 0xff);
}

/* Basically does the reverse of SockList_AddInt, but on
 * strings instead.  Same for the GetShort, but for 16 bits.
 */
int
GetInt_String (unsigned char *data)
{
  return ((data[0] << 24) + (data[1] << 16) + (data[2] << 8) + data[3]);
}

short
GetShort_String (unsigned char *data)
{
  return ((data[0] << 8) + data[1]);
}

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

/**
 * This reads from fd and puts the data in sl.  We return true if we think
 * we have a full packet, 0 if we have a partial packet.  The only processing
 * we do is remove the intial size value.  len (As passed) is the size of the
 * buffer allocated in the socklist.  We make the assumption the buffer is
 * at least 2 bytes long.
 */

int
SockList_ReadPacket (int fd, SockList * sl, int len)
{
  int stat, toread;

  /* Sanity check - shouldn't happen */
  if (sl->len < 0)
    {
      abort ();
    }
  /* We already have a partial packet */
  if (sl->len < 2)
    {
#ifdef WIN32                    /* ***WIN32 SockList_ReadPacket: change read() to recv() */

      stat = recv (fd, sl->buf + sl->len, 2 - sl->len, 0);

#else
      do
        {
          stat = read (fd, sl->buf + sl->len, 2 - sl->len);
        }
      while ((stat == -1) && (errno == EINTR));
#endif
      if (stat < 0)
        {
          /* In non blocking mode, EAGAIN is set when there is no
           * data available.
           */
#ifdef WIN32                    /* ***WIN32 SockList_ReadPacket: error handling for win32 */
          if ((stat == -1) && WSAGetLastError () != WSAEWOULDBLOCK)
            {
              if (WSAGetLastError () == WSAECONNRESET)
                LOG (llevDebug, "Connection closed by client\n");
              else
                {
                  LOG (llevDebug, "ReadPacket got error %d, returning 0\n", WSAGetLastError ());
                }
              return -1;        /* kick this user! */
            }
#else
          if (errno != EAGAIN && errno != EWOULDBLOCK)
            {
              LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
            }
#endif
          return 0;             /*Error */
        }
      if (stat == 0)
        return -1;
      sl->len += stat;
#ifdef CS_LOGSTATS
      cst_tot.ibytes += stat;
      cst_lst.ibytes += stat;
#endif
      if (stat < 2)
        return 0;               /* Still don't have a full packet */
    }
  /* Figure out how much more data we need to read.  Add 2 from the
   * end of this - size header information is not included.
   */
  toread = 2 + (sl->buf[0] << 8) + sl->buf[1] - sl->len;
  if ((toread + sl->len) >= len)
    {
      LOG (llevError, "SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n", toread + sl->len, len);
      /* Quick hack in case for 'oldsocketmode' input.  If we are
       * closing the socket anyways, then reading this extra 100 bytes
       * shouldn't hurt.
       */
#ifdef WIN32                    /* ***win32 SockList_ReadPacket: change read() to recv() */
      recv (fd, sl->buf + 2, 100, 0);
#else
      read (fd, sl->buf + 2, 100);
#endif /* end win32 */

      /* return error so the socket is closed */
      return -1;
    }
  do
    {
#ifdef WIN32                    /* ***win32 SockList_ReadPacket: change read() to recv() */
      stat = recv (fd, sl->buf + sl->len, toread, 0);
#else
      do
        {
          stat = read (fd, sl->buf + sl->len, toread);
        }
      while ((stat < 0) && (errno == EINTR));
#endif
      if (stat < 0)
        {

#ifdef WIN32                    /* ***win32 SockList_ReadPacket: change error handling for win32 */
          if ((stat == -1) && WSAGetLastError () != WSAEWOULDBLOCK)
            {
              if (WSAGetLastError () == WSAECONNRESET)
                LOG (llevDebug, "Connection closed by client\n");
              else
                {
                  LOG (llevDebug, "ReadPacket got error %d, returning 0\n", WSAGetLastError ());
                }
              return -1;        /* kick this user! */
            }
#else
          if (errno != EAGAIN && errno != EWOULDBLOCK)
            {
              LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
            }
#endif
          return 0;             /*Error */
        }
      if (stat == 0)
        return -1;
      sl->len += stat;
#ifdef CS_LOGSTATS
      cst_tot.ibytes += stat;
      cst_lst.ibytes += stat;
#endif
      toread -= stat;
      if (toread == 0)
        return 1;
      if (toread < 0)
        {
          LOG (llevError, "SockList_ReadPacket: Read more bytes than desired.\n");
          return 1;
        }
    }
  while (toread > 0);
  return 0;
}

/*******************************************************************************
 *
 * 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.
 */

static void
add_to_buffer (NewSocket * ns, char *buf, int len)
{
  int avail, end;

  if ((len + ns->outputbuffer.len) > SOCKETBUFSIZE)
    {
      LOG (llevDebug, "Socket on fd %d has overrun internal buffer - marking as dead\n", ns->fd);
      ns->status = Ns_Dead;
      return;
    }

  /* data + end is where we start putting the new data.  The last byte
   * currently in use is actually data + end -1
   */

  end = ns->outputbuffer.start + ns->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 (ns->outputbuffer.data + end, buf, len);
    }
  else
    {
      memcpy (ns->outputbuffer.data + end, buf, avail);
      memcpy (ns->outputbuffer.data, buf + avail, len - avail);
    }
  ns->outputbuffer.len += len;
#if 0
  LOG (llevDebug, "Added %d to output buffer, total length now %d, start=%d\n", len, ns->outputbuffer.len, ns->outputbuffer.start);
#endif
}

/**
 * Writes data to socket.
 *
 * When the socket is clear to write, and we have backlogged data, this
 * is called to write it out.
 */
void
write_socket_buffer (NewSocket * ns)
{
  int amt, max;

  if (ns->outputbuffer.len == 0)
    {
      LOG (llevDebug, "write_socket_buffer called when there is no data, fd=%d\n", ns->fd);
      return;
    }

  do
    {
      max = SOCKETBUFSIZE - ns->outputbuffer.start;
      if (ns->outputbuffer.len < max)
        max = ns->outputbuffer.len;

#ifdef WIN32                    /* ***win32 write_socket_buffer: change write() to send() */
      amt = send (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max, 0);
#else
      do
        {
          amt = write (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
        }
      while ((amt < 0) && (errno == EINTR));
#endif

      if (amt < 0)
        {                       /* We got an error */

#ifdef WIN32                    /* ***win32 write_socket_buffer: change error handling */
          if (amt == -1 && WSAGetLastError () != WSAEWOULDBLOCK)
            {
              LOG (llevError, "New socket write failed (wsb) (%d).\n", WSAGetLastError ());
#else
          if (errno != EWOULDBLOCK)
            {
              LOG (llevError, "New socket write failed (wsb) (%d: %s).\n", errno, strerror (errno));
#endif
              ns->status = Ns_Dead;
              return;
            }
          else
            {                   /* EWOULDBLOCK */
              /* can't write it, so store it away. */
              ns->can_write = 0;
              return;
            }
        }
      ns->outputbuffer.start += amt;
      /* wrap back to start of buffer */
      if (ns->outputbuffer.start == SOCKETBUFSIZE)
        ns->outputbuffer.start = 0;
      ns->outputbuffer.len -= amt;
#ifdef CS_LOGSTATS
      cst_tot.obytes += amt;
      cst_lst.obytes += amt;
#endif
    }
  while (ns->outputbuffer.len > 0);
}

/**
 * This writes data to the socket. - It is very low level -
 * all we try and do is write out the data to the socket
 * provided (ns).  buf is the data to write, len is the number
 * of bytes to write.  IT doesn't return anything - rather, it
 * updates the ns structure if we get an  error.
 */
void
Write_To_Socket (NewSocket * ns, char *buf, int len)
{
  int amt = 0;
  char *pos = buf;

  if (ns->status == Ns_Dead || !buf)
    {
      LOG (llevDebug, "Write_To_Socket called with dead socket\n");
      return;
    }

#ifndef __GNU__                 /* This caused problems on Hurd */
  if (!ns->can_write)
    {
      add_to_buffer (ns, buf, len);
      return;
    }
#endif
  /* If we manage to write more than we wanted, take it as a bonus */
  while (len > 0)
    {

#ifdef WIN32                    /* ***win32 Write_To_Socket: change write() to send() */
      amt = send (ns->fd, pos, len, 0);
#else
      do
        {
          amt = write (ns->fd, pos, len);
        }
      while ((amt < 0) && (errno == EINTR));
#endif

      if (amt < 0)
        {                       /* We got an error */
#ifdef WIN32                    /* ***win32 Write_To_Socket: change error handling */
          if (amt == -1 && WSAGetLastError () != WSAEWOULDBLOCK)
            {
              LOG (llevError, "New socket write failed WTS (%d).\n", WSAGetLastError ());
#else
          if (errno != EWOULDBLOCK)
            {
              LOG (llevError, "New socket write failed WTS (%d: %s).\n",        /* ---WIN32 */
                   errno, strerror (errno));
#endif
              ns->status = Ns_Dead;
              return;
            }
          else
            {                   /* EWOULDBLOCK */
              /* can't write it, so store it away. */
              add_to_buffer (ns, pos, len);
              ns->can_write = 0;
              return;
            }
        }
      /* amt gets set to 0 above in blocking code, so we do this as
       * an else if to make sure we don't reprocess it.
       */
      else if (amt == 0)
        {
          LOG (llevError, "Write_To_Socket: No data written out.\n");
        }
      len -= amt;
      pos += amt;
#ifdef CS_LOGSTATS
      cst_tot.obytes += amt;
      cst_lst.obytes += amt;
#endif
    }
}


/**
 * Takes a string of data, and writes it out to the socket. A very handy
 * shortcut function.
 */
void
cs_write_string (NewSocket * ns, const char *buf, int len)
{
  SockList sl;

  sl.len = len;
  sl.buf = (unsigned char *) buf;
  Send_With_Handling (ns, &sl);
}


/**
 * Calls Write_To_Socket to send data to the client.
 *
 * The only difference in this function is that we take a SockList
 *, and we prepend the length information.
 */
void
Send_With_Handling (NewSocket * ns, SockList * msg)
{
  unsigned char sbuf[4];

  if (ns->status == Ns_Dead || !msg)
    return;

  if (msg->len >= MAXSOCKBUF)
    {
      LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", msg->len);
      /* Almost certainly we've overflowed a buffer, so quite now to make
       * it easier to debug.
       */
      abort ();
    }
  sbuf[0] = ((uint32) (msg->len) >> 8) & 0xFF;
  sbuf[1] = ((uint32) (msg->len)) & 0xFF;
  if (ns->status != Ns_Old)
    Write_To_Socket (ns, (char *) sbuf, 2);
  Write_To_Socket (ns, (char *) msg->buf, msg->len);
}

/**
 * Takes a string of data, and writes it out to the socket. A very handy
 * shortcut function.
 */
void
Write_String_To_Socket (NewSocket * ns, char *buf, int len)
{
  SockList sl;

  sl.len = len;
  sl.buf = (unsigned char *) buf;
  Send_With_Handling (ns, &sl);
}


/******************************************************************************
 *
 * 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.max_conn = socket_info.nconns;
  cst_lst.time_start = now;
}
#endif
Revision:	1.5
Committed:	Sun Sep 10 13:43:33 2006 UTC (17 years, 8 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.4:	+311 -253 lines
Log Message:	indent
#	Content
1
2	/*
3	* static char *rcsid_sockets_c =
4	* "$Id: lowlevel.C,v 1.4 2006-08-30 16:30:37 root Exp $";
5	*/
6
7	/*
8	CrossFire, A Multiplayer game for X-windows
9
10	Copyright (C) 1992 Frank Tore Johansen
11
12	This program is free software; you can redistribute it and/or modify
13	it under the terms of the GNU General Public License as published by
14	the Free Software Foundation; either version 2 of the License, or
15	(at your option) any later version.
16
17	This program is distributed in the hope that it will be useful,
18	but WITHOUT ANY WARRANTY; without even the implied warranty of
19	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20	GNU General Public License for more details.
21
22	You should have received a copy of the GNU General Public License
23	along with this program; if not, write to the Free Software
24	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25
26	The author can be reached via e-mail to mark@pyramid.com
27	*/
28
29	/**
30	* \file
31	* Low-level socket-related functions.
32	*
33	* \date 2003-12-02
34	*
35	* Contains some base functions that both the client and server
36	* can use. As such, depending what we are being compiled for will
37	* determine what we can include. the client is designed have
38	* CFCLIENT defined as part of its compile flags.
39	*/
40
41	using namespace std;
42
43	#include <global.h>
44	#include <newclient.h>
45	#include <sproto.h>
46
47	#ifdef __linux__
48	# include <sys/types.h>
49	# include <sys/socket.h>
50	# include <netinet/in.h>
51	# define TCP_HZ 1000 // sorry...
52	# include <netinet/tcp.h>
53	#endif
54
55	// use a really low timeout, as it doesn't cost any bandwidth, and you can
56	// easily die in 20 seconds...
57	#define SOCKET_TIMEOUT1 10
58	#define SOCKET_TIMEOUT2 20
59
60	void
61	Socket_Flush (NewSocket * ns)
62	{
63	#ifdef __linux__
64	// check time of last ack, and, if too old, kill connection
65	struct tcp_info tcpi;
66	socklen_t len = sizeof (tcpi);
67
68	if (!getsockopt (ns->fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
69	{
70	unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;
71
72	if (tcpi.tcpi_unacked && SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL // ack delayed for 20s
73	&& SOCKET_TIMEOUT2 * TCP_HZ < 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", ns->fd,
76	(unsigned) tcpi.tcpi_last_ack_recv, (unsigned) tcpi.tcpi_last_data_sent, (unsigned) tcpi.tcpi_unacked);
77	ns->status = Ns_Dead;
78	}
79	}
80
81	int val;
82
83	val = 0;
84	setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
85	val = 1;
86	setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
87	#endif
88	}
89
90	/***********************************************************************
91	*
92	* SockList functions/utilities
93	*
94	**********************************************************************/
95
96	void
97	SockList_Init (SockList * sl)
98	{
99	sl->len = 0;
100	sl->buf = NULL;
101	}
102
103	void
104	SockList_AddInt (SockList * sl, uint32 data)
105	{
106	sl->buf[sl->len++] = (data >> 24) & 0xff;
107	sl->buf[sl->len++] = (data >> 16) & 0xff;
108	sl->buf[sl->len++] = (data >> 8) & 0xff;
109	sl->buf[sl->len++] = data & 0xff;
110	}
111
112	void
113	SockList_AddInt64 (SockList * sl, uint64 data)
114	{
115	sl->buf[sl->len++] = (char) ((data >> 56) & 0xff);
116	sl->buf[sl->len++] = (char) ((data >> 48) & 0xff);
117	sl->buf[sl->len++] = (char) ((data >> 40) & 0xff);
118	sl->buf[sl->len++] = (char) ((data >> 32) & 0xff);
119
120	sl->buf[sl->len++] = (char) ((data >> 24) & 0xff);
121	sl->buf[sl->len++] = (char) ((data >> 16) & 0xff);
122	sl->buf[sl->len++] = (char) ((data >> 8) & 0xff);
123	sl->buf[sl->len++] = (char) (data & 0xff);
124	}
125
126	/* Basically does the reverse of SockList_AddInt, but on
127	* strings instead. Same for the GetShort, but for 16 bits.
128	*/
129	int
130	GetInt_String (unsigned char *data)
131	{
132	return ((data[0] << 24) + (data[1] << 16) + (data[2] << 8) + data[3]);
133	}
134
135	short
136	GetShort_String (unsigned char *data)
137	{
138	return ((data[0] << 8) + data[1]);
139	}
140
141	/******************************************************************************
142	*
143	* Start of read routines.
144	*
145	******************************************************************************/
146
147	/**
148	* This reads from fd and puts the data in sl. We return true if we think
149	* we have a full packet, 0 if we have a partial packet. The only processing
150	* we do is remove the intial size value. len (As passed) is the size of the
151	* buffer allocated in the socklist. We make the assumption the buffer is
152	* at least 2 bytes long.
153	*/
154
155	int
156	SockList_ReadPacket (int fd, SockList * sl, int len)
157	{
158	int stat, toread;
159
160	/* Sanity check - shouldn't happen */
161	if (sl->len < 0)
162	{
163	abort ();
164	}
165	/* We already have a partial packet */
166	if (sl->len < 2)
167	{
168	#ifdef WIN32 /* **WIN32 SockList_ReadPacket: change read() to recv() /
169
170	stat = recv (fd, sl->buf + sl->len, 2 - sl->len, 0);
171
172	#else
173	do
174	{
175	stat = read (fd, sl->buf + sl->len, 2 - sl->len);
176	}
177	while ((stat == -1) && (errno == EINTR));
178	#endif
179	if (stat < 0)
180	{
181	/* In non blocking mode, EAGAIN is set when there is no
182	* data available.
183	*/
184	#ifdef WIN32 /* **WIN32 SockList_ReadPacket: error handling for win32 /
185	if ((stat == -1) && WSAGetLastError () != WSAEWOULDBLOCK)
186	{
187	if (WSAGetLastError () == WSAECONNRESET)
188	LOG (llevDebug, "Connection closed by client\n");
189	else
190	{
191	LOG (llevDebug, "ReadPacket got error %d, returning 0\n", WSAGetLastError ());
192	}
193	return -1; /* kick this user! */
194	}
195	#else
196	if (errno != EAGAIN && errno != EWOULDBLOCK)
197	{
198	LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
199	}
200	#endif
201	return 0; /Error /
202	}
203	if (stat == 0)
204	return -1;
205	sl->len += stat;
206	#ifdef CS_LOGSTATS
207	cst_tot.ibytes += stat;
208	cst_lst.ibytes += stat;
209	#endif
210	if (stat < 2)
211	return 0; /* Still don't have a full packet */
212	}
213	/* Figure out how much more data we need to read. Add 2 from the
214	* end of this - size header information is not included.
215	*/
216	toread = 2 + (sl->buf[0] << 8) + sl->buf[1] - sl->len;
217	if ((toread + sl->len) >= len)
218	{
219	LOG (llevError, "SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n", toread + sl->len, len);
220	/* Quick hack in case for 'oldsocketmode' input. If we are
221	* closing the socket anyways, then reading this extra 100 bytes
222	* shouldn't hurt.
223	*/
224	#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
225	recv (fd, sl->buf + 2, 100, 0);
226	#else
227	read (fd, sl->buf + 2, 100);
228	#endif /* end win32 */
229
230	/* return error so the socket is closed */
231	return -1;
232	}
233	do
234	{
235	#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
236	stat = recv (fd, sl->buf + sl->len, toread, 0);
237	#else
238	do
239	{
240	stat = read (fd, sl->buf + sl->len, toread);
241	}
242	while ((stat < 0) && (errno == EINTR));
243	#endif
244	if (stat < 0)
245	{
246
247	#ifdef WIN32 /* **win32 SockList_ReadPacket: change error handling for win32 /
248	if ((stat == -1) && WSAGetLastError () != WSAEWOULDBLOCK)
249	{
250	if (WSAGetLastError () == WSAECONNRESET)
251	LOG (llevDebug, "Connection closed by client\n");
252	else
253	{
254	LOG (llevDebug, "ReadPacket got error %d, returning 0\n", WSAGetLastError ());
255	}
256	return -1; /* kick this user! */
257	}
258	#else
259	if (errno != EAGAIN && errno != EWOULDBLOCK)
260	{
261	LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
262	}
263	#endif
264	return 0; /Error /
265	}
266	if (stat == 0)
267	return -1;
268	sl->len += stat;
269	#ifdef CS_LOGSTATS
270	cst_tot.ibytes += stat;
271	cst_lst.ibytes += stat;
272	#endif
273	toread -= stat;
274	if (toread == 0)
275	return 1;
276	if (toread < 0)
277	{
278	LOG (llevError, "SockList_ReadPacket: Read more bytes than desired.\n");
279	return 1;
280	}
281	}
282	while (toread > 0);
283	return 0;
284	}
285
286	/*******************************************************************************
287	*
288	* Start of write related routines.
289	*
290	******************************************************************************/
291
292	/**
293	* Adds data to a socket buffer for whatever reason.
294	*
295	* ns is the socket we are adding the data to, buf is the start of the
296	* data, and len is the number of bytes to add.
297	*/
298
299	static void
300	add_to_buffer (NewSocket * ns, char *buf, int len)
301	{
302	int avail, end;
303
304	if ((len + ns->outputbuffer.len) > SOCKETBUFSIZE)
305	{
306	LOG (llevDebug, "Socket on fd %d has overrun internal buffer - marking as dead\n", ns->fd);
307	ns->status = Ns_Dead;
308	return;
309	}
310
311	/* data + end is where we start putting the new data. The last byte
312	* currently in use is actually data + end -1
313	*/
314
315	end = ns->outputbuffer.start + ns->outputbuffer.len;
316	/* The buffer is already in a wrapped state, so adjust end */
317	if (end >= SOCKETBUFSIZE)
318	end -= SOCKETBUFSIZE;
319	avail = SOCKETBUFSIZE - end;
320
321	/* We can all fit it behind the current data without wrapping */
322	if (avail >= len)
323	{
324	memcpy (ns->outputbuffer.data + end, buf, len);
325	}
326	else
327	{
328	memcpy (ns->outputbuffer.data + end, buf, avail);
329	memcpy (ns->outputbuffer.data, buf + avail, len - avail);
330	}
331	ns->outputbuffer.len += len;
332	#if 0
333	LOG (llevDebug, "Added %d to output buffer, total length now %d, start=%d\n", len, ns->outputbuffer.len, ns->outputbuffer.start);
334	#endif
335	}
336
337	/**
338	* Writes data to socket.
339	*
340	* When the socket is clear to write, and we have backlogged data, this
341	* is called to write it out.
342	*/
343	void
344	write_socket_buffer (NewSocket * ns)
345	{
346	int amt, max;
347
348	if (ns->outputbuffer.len == 0)
349	{
350	LOG (llevDebug, "write_socket_buffer called when there is no data, fd=%d\n", ns->fd);
351	return;
352	}
353
354	do
355	{
356	max = SOCKETBUFSIZE - ns->outputbuffer.start;
357	if (ns->outputbuffer.len < max)
358	max = ns->outputbuffer.len;
359
360	#ifdef WIN32 /* **win32 write_socket_buffer: change write() to send() /
361	amt = send (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max, 0);
362	#else
363	do
364	{
365	amt = write (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
366	}
367	while ((amt < 0) && (errno == EINTR));
368	#endif
369
370	if (amt < 0)
371	{ /* We got an error */
372
373	#ifdef WIN32 /* **win32 write_socket_buffer: change error handling /
374	if (amt == -1 && WSAGetLastError () != WSAEWOULDBLOCK)
375	{
376	LOG (llevError, "New socket write failed (wsb) (%d).\n", WSAGetLastError ());
377	#else
378	if (errno != EWOULDBLOCK)
379	{
380	LOG (llevError, "New socket write failed (wsb) (%d: %s).\n", errno, strerror (errno));
381	#endif
382	ns->status = Ns_Dead;
383	return;
384	}
385	else
386	{ /* EWOULDBLOCK */
387	/* can't write it, so store it away. */
388	ns->can_write = 0;
389	return;
390	}
391	}
392	ns->outputbuffer.start += amt;
393	/* wrap back to start of buffer */
394	if (ns->outputbuffer.start == SOCKETBUFSIZE)
395	ns->outputbuffer.start = 0;
396	ns->outputbuffer.len -= amt;
397	#ifdef CS_LOGSTATS
398	cst_tot.obytes += amt;
399	cst_lst.obytes += amt;
400	#endif
401	}
402	while (ns->outputbuffer.len > 0);
403	}
404
405	/**
406	* This writes data to the socket. - It is very low level -
407	* all we try and do is write out the data to the socket
408	* provided (ns). buf is the data to write, len is the number
409	* of bytes to write. IT doesn't return anything - rather, it
410	* updates the ns structure if we get an error.
411	*/
412	void
413	Write_To_Socket (NewSocket * ns, char *buf, int len)
414	{
415	int amt = 0;
416	char *pos = buf;
417
418	if (ns->status == Ns_Dead \|\| !buf)
419	{
420	LOG (llevDebug, "Write_To_Socket called with dead socket\n");
421	return;
422	}
423
424	#ifndef __GNU__ /* This caused problems on Hurd */
425	if (!ns->can_write)
426	{
427	add_to_buffer (ns, buf, len);
428	return;
429	}
430	#endif
431	/* If we manage to write more than we wanted, take it as a bonus */
432	while (len > 0)
433	{
434
435	#ifdef WIN32 /* **win32 Write_To_Socket: change write() to send() /
436	amt = send (ns->fd, pos, len, 0);
437	#else
438	do
439	{
440	amt = write (ns->fd, pos, len);
441	}
442	while ((amt < 0) && (errno == EINTR));
443	#endif
444
445	if (amt < 0)
446	{ /* We got an error */
447	#ifdef WIN32 /* **win32 Write_To_Socket: change error handling /
448	if (amt == -1 && WSAGetLastError () != WSAEWOULDBLOCK)
449	{
450	LOG (llevError, "New socket write failed WTS (%d).\n", WSAGetLastError ());
451	#else
452	if (errno != EWOULDBLOCK)
453	{
454	LOG (llevError, "New socket write failed WTS (%d: %s).\n", /* ---WIN32 */
455	errno, strerror (errno));
456	#endif
457	ns->status = Ns_Dead;
458	return;
459	}
460	else
461	{ /* EWOULDBLOCK */
462	/* can't write it, so store it away. */
463	add_to_buffer (ns, pos, len);
464	ns->can_write = 0;
465	return;
466	}
467	}
468	/* amt gets set to 0 above in blocking code, so we do this as
469	* an else if to make sure we don't reprocess it.
470	*/
471	else if (amt == 0)
472	{
473	LOG (llevError, "Write_To_Socket: No data written out.\n");
474	}
475	len -= amt;
476	pos += amt;
477	#ifdef CS_LOGSTATS
478	cst_tot.obytes += amt;
479	cst_lst.obytes += amt;
480	#endif
481	}
482	}
483
484
485	/**
486	* Takes a string of data, and writes it out to the socket. A very handy
487	* shortcut function.
488	*/
489	void
490	cs_write_string (NewSocket * ns, const char *buf, int len)
491	{
492	SockList sl;
493
494	sl.len = len;
495	sl.buf = (unsigned char *) buf;
496	Send_With_Handling (ns, &sl);
497	}
498
499
500	/**
501	* Calls Write_To_Socket to send data to the client.
502	*
503	* The only difference in this function is that we take a SockList
504	*, and we prepend the length information.
505	*/
506	void
507	Send_With_Handling (NewSocket * ns, SockList * msg)
508	{
509	unsigned char sbuf[4];
510
511	if (ns->status == Ns_Dead \|\| !msg)
512	return;
513
514	if (msg->len >= MAXSOCKBUF)
515	{
516	LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", msg->len);
517	/* Almost certainly we've overflowed a buffer, so quite now to make
518	* it easier to debug.
519	*/
520	abort ();
521	}
522	sbuf[0] = ((uint32) (msg->len) >> 8) & 0xFF;
523	sbuf[1] = ((uint32) (msg->len)) & 0xFF;
524	if (ns->status != Ns_Old)
525	Write_To_Socket (ns, (char *) sbuf, 2);
526	Write_To_Socket (ns, (char *) msg->buf, msg->len);
527	}
528
529	/**
530	* Takes a string of data, and writes it out to the socket. A very handy
531	* shortcut function.
532	*/
533	void
534	Write_String_To_Socket (NewSocket * ns, char *buf, int len)
535	{
536	SockList sl;
537
538	sl.len = len;
539	sl.buf = (unsigned char *) buf;
540	Send_With_Handling (ns, &sl);
541	}
542
543
544	/******************************************************************************
545	*
546	* statistics logging functions.
547	*
548	******************************************************************************/
549
550	#ifdef CS_LOGSTATS
551
552	/* cst_tot is for the life of the server, cst_last is for the last series of
553	* stats
554	*/
555	CS_Stats cst_tot, cst_lst;
556
557	/**
558	* Writes out the gathered stats. We clear cst_lst.
559	*/
560	void
561	write_cs_stats (void)
562	{
563	time_t now = time (NULL);
564
565	/* If no connections recently, don't both to log anything */
566	if (cst_lst.ibytes == 0 && cst_lst.obytes == 0)
567	return;
568
569	/* CSSTAT is put in so scripts can easily find the line */
570	LOG (llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
571	ctime (&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
572	now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes, cst_lst.max_conn, now - cst_lst.time_start);
573	cst_lst.ibytes = 0;
574	cst_lst.obytes = 0;
575	cst_lst.max_conn = socket_info.nconns;
576	cst_lst.time_start = now;
577	}
578	#endif