server/socket/lowlevel.C

/*
    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>
#include <cstdarg>

#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
 *
 **********************************************************************/

SockList &SockList::operator <<(const data   &v)
{
  if (v.len)
    {
      memcpy (buf + len, v.ptr, v.len);
      len += v.len;
    }

  return *this;
}

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

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

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

void
SockList::printf (const char *format, ...)
{
  va_list ap;
  va_start (ap, format);

  len += vsprintf ((char *)buf + len, format, ap);

  va_end (ap);
}

/* 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)
    {
      do
        {
          stat = read (fd, sl->buf + sl->len, 2 - sl->len);
        }
      while ((stat == -1) && (errno == EINTR));

      if (stat < 0)
        {
          /* In non blocking mode, EAGAIN is set when there is no
           * data available.
           */
          if (errno != EAGAIN && errno != EWOULDBLOCK)
            {
              LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
            }
          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.
       */
      read (fd, sl->buf + 2, 100);

      /* return error so the socket is closed */
      return -1;
    }
  do
    {
      do
        {
          stat = read (fd, sl->buf + sl->len, toread);
        }
      while ((stat < 0) && (errno == EINTR));
      if (stat < 0)
        {

          if (errno != EAGAIN && errno != EWOULDBLOCK)
            {
              LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
            }
          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;

      do
        {
          amt = write (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
        }
      while ((amt < 0) && (errno == EINTR));

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

          if (errno != EWOULDBLOCK)
            {
              LOG (llevError, "New socket write failed (wsb) (%d: %s).\n", errno, strerror (errno));
              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)
    {

      do
        {
          amt = write (ns->fd, pos, len);
        }
      while ((amt < 0) && (errno == EINTR));

      if (amt < 0)
        {                       /* We got an error */
          if (errno != EWOULDBLOCK)
            {
              LOG (llevError, "New socket write failed WTS (%d: %s).\n",        /* ---WIN32 */
                   errno, strerror (errno));
              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:	1.11
Committed:	Wed Dec 13 21:27:09 2006 UTC (19 years, 9 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.10:	+30 -22 lines
Log Message:	continued simplifying network code, partially removed support for sc protocol 1026
#	User	Rev	Content
1	elmex	1.1	/*
2			CrossFire, A Multiplayer game for X-windows
3
4			Copyright (C) 1992 Frank Tore Johansen
5
6			This program is free software; you can redistribute it and/or modify
7			it under the terms of the GNU General Public License as published by
8			the Free Software Foundation; either version 2 of the License, or
9			(at your option) any later version.
10
11			This program is distributed in the hope that it will be useful,
12			but WITHOUT ANY WARRANTY; without even the implied warranty of
13			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			GNU General Public License for more details.
15
16			You should have received a copy of the GNU General Public License
17			along with this program; if not, write to the Free Software
18			Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19
20			The author can be reached via e-mail to mark@pyramid.com
21			*/
22
23			/**
24			* \file
25			* Low-level socket-related functions.
26			*
27			* \date 2003-12-02
28			*
29			* Contains some base functions that both the client and server
30			* can use. As such, depending what we are being compiled for will
31			* determine what we can include. the client is designed have
32			* CFCLIENT defined as part of its compile flags.
33			*/
34
35			using namespace std;
36
37			#include <global.h>
38			#include <newclient.h>
39			#include <sproto.h>
40	root	1.11	#include <cstdarg>
41	elmex	1.1
42			#ifdef __linux__
43			# include <sys/types.h>
44			# include <sys/socket.h>
45			# include <netinet/in.h>
46	root	1.5	# define TCP_HZ 1000 // sorry...
47	elmex	1.1	# include <netinet/tcp.h>
48			#endif
49
50			// use a really low timeout, as it doesn't cost any bandwidth, and you can
51			// easily die in 20 seconds...
52			#define SOCKET_TIMEOUT1 10
53			#define SOCKET_TIMEOUT2 20
54
55	root	1.5	void
56			Socket_Flush (NewSocket * ns)
57	elmex	1.1	{
58			#ifdef __linux__
59			// check time of last ack, and, if too old, kill connection
60			struct tcp_info tcpi;
61			socklen_t len = sizeof (tcpi);
62
63			if (!getsockopt (ns->fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
64			{
65			unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;
66
67	root	1.5	if (tcpi.tcpi_unacked && SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL // ack delayed for 20s
68			&& SOCKET_TIMEOUT2 * TCP_HZ < tcpi.tcpi_last_data_sent) // no data sent for 10s
69	elmex	1.1	{
70	root	1.3	LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd,
71	root	1.5	(unsigned) tcpi.tcpi_last_ack_recv, (unsigned) tcpi.tcpi_last_data_sent, (unsigned) tcpi.tcpi_unacked);
72	elmex	1.1	ns->status = Ns_Dead;
73			}
74			}
75
76			int val;
77	root	1.5
78	root	1.9	val = 0; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
79			val = 1; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
80	elmex	1.1	#endif
81			}
82
83			/***********************************************************************
84			*
85			* SockList functions/utilities
86			*
87			**********************************************************************/
88
89	root	1.11	SockList &SockList::operator <<(const data &v)
90	elmex	1.1	{
91	root	1.11	if (v.len)
92			{
93			memcpy (buf + len, v.ptr, v.len);
94			len += v.len;
95			}
96	root	1.9
97	root	1.11	return *this;
98			}
99	root	1.9
100	root	1.11	SockList &SockList::operator <<(const data8 &v)
101			{
102			unsigned int len = min (v.len, 0x00FF);
103			return *this << uint8 (len) << data (v.ptr, len);
104	elmex	1.1	}
105
106	root	1.9	SockList &SockList::operator <<(const data16 &v)
107	elmex	1.1	{
108	root	1.11	unsigned int len = min (v.len, 0xFFFF);
109			return *this << uint16 (len) << data (v.ptr, len);
110			}
111	root	1.9
112	root	1.11	SockList &SockList::operator <<(const char *v)
113			{
114			return *this << data (v, strlen (v ? v : 0));
115	elmex	1.1	}
116
117	root	1.11	void
118			SockList::printf (const char *format, ...)
119	root	1.10	{
120	root	1.11	va_list ap;
121			va_start (ap, format);
122
123			len += vsprintf ((char *)buf + len, format, ap);
124	root	1.10
125	root	1.11	va_end (ap);
126	root	1.10	}
127
128	elmex	1.1	/* Basically does the reverse of SockList_AddInt, but on
129			* strings instead. Same for the GetShort, but for 16 bits.
130			*/
131	root	1.5	int
132			GetInt_String (unsigned char *data)
133	elmex	1.1	{
134	root	1.5	return ((data[0] << 24) + (data[1] << 16) + (data[2] << 8) + data[3]);
135	elmex	1.1	}
136
137	root	1.5	short
138			GetShort_String (unsigned char *data)
139			{
140			return ((data[0] << 8) + data[1]);
141	elmex	1.1	}
142
143			/******************************************************************************
144			*
145			* Start of read routines.
146			*
147			******************************************************************************/
148
149			/**
150			* This reads from fd and puts the data in sl. We return true if we think
151			* we have a full packet, 0 if we have a partial packet. The only processing
152			* we do is remove the intial size value. len (As passed) is the size of the
153			* buffer allocated in the socklist. We make the assumption the buffer is
154			* at least 2 bytes long.
155			*/
156	root	1.5
157			int
158	root	1.11	SockList_ReadPacket (int fd, SockList *sl, int len)
159	elmex	1.1	{
160	root	1.5	int stat, toread;
161	elmex	1.1
162	root	1.5	/* Sanity check - shouldn't happen */
163			if (sl->len < 0)
164			{
165			abort ();
166	elmex	1.1	}
167	root	1.5	/* We already have a partial packet */
168			if (sl->len < 2)
169			{
170			do
171			{
172			stat = read (fd, sl->buf + sl->len, 2 - sl->len);
173			}
174			while ((stat == -1) && (errno == EINTR));
175	pippijn	1.8
176	root	1.5	if (stat < 0)
177			{
178			/* In non blocking mode, EAGAIN is set when there is no
179			* data available.
180			*/
181			if (errno != EAGAIN && errno != EWOULDBLOCK)
182			{
183			LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
184	root	1.3	}
185	root	1.5	return 0; /Error /
186	root	1.3	}
187	root	1.5	if (stat == 0)
188			return -1;
189			sl->len += stat;
190	elmex	1.1	#ifdef CS_LOGSTATS
191	root	1.5	cst_tot.ibytes += stat;
192			cst_lst.ibytes += stat;
193	elmex	1.1	#endif
194	root	1.5	if (stat < 2)
195			return 0; /* Still don't have a full packet */
196	elmex	1.1	}
197	root	1.5	/* Figure out how much more data we need to read. Add 2 from the
198			* end of this - size header information is not included.
199			*/
200			toread = 2 + (sl->buf[0] << 8) + sl->buf[1] - sl->len;
201			if ((toread + sl->len) >= len)
202			{
203			LOG (llevError, "SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n", toread + sl->len, len);
204			/* Quick hack in case for 'oldsocketmode' input. If we are
205			* closing the socket anyways, then reading this extra 100 bytes
206			* shouldn't hurt.
207			*/
208			read (fd, sl->buf + 2, 100);
209	elmex	1.1
210	root	1.5	/* return error so the socket is closed */
211			return -1;
212	elmex	1.1	}
213	root	1.5	do
214			{
215			do
216			{
217			stat = read (fd, sl->buf + sl->len, toread);
218			}
219			while ((stat < 0) && (errno == EINTR));
220			if (stat < 0)
221			{
222
223			if (errno != EAGAIN && errno != EWOULDBLOCK)
224			{
225			LOG (llevDebug, "ReadPacket got error %s, returning 0\n", strerror (errno));
226	root	1.3	}
227	root	1.5	return 0; /Error /
228	root	1.3	}
229	root	1.5	if (stat == 0)
230			return -1;
231			sl->len += stat;
232	elmex	1.1	#ifdef CS_LOGSTATS
233	root	1.5	cst_tot.ibytes += stat;
234			cst_lst.ibytes += stat;
235	elmex	1.1	#endif
236	root	1.5	toread -= stat;
237			if (toread == 0)
238			return 1;
239			if (toread < 0)
240			{
241			LOG (llevError, "SockList_ReadPacket: Read more bytes than desired.\n");
242			return 1;
243	root	1.3	}
244	root	1.5	}
245			while (toread > 0);
246			return 0;
247	elmex	1.1	}
248
249			/*******************************************************************************
250			*
251			* Start of write related routines.
252			*
253			******************************************************************************/
254
255			/**
256			* Adds data to a socket buffer for whatever reason.
257			*
258			* ns is the socket we are adding the data to, buf is the start of the
259			* data, and len is the number of bytes to add.
260			*/
261
262	root	1.5	static void
263			add_to_buffer (NewSocket * ns, char *buf, int len)
264	elmex	1.1	{
265	root	1.5	int avail, end;
266	elmex	1.1
267	root	1.5	if ((len + ns->outputbuffer.len) > SOCKETBUFSIZE)
268			{
269			LOG (llevDebug, "Socket on fd %d has overrun internal buffer - marking as dead\n", ns->fd);
270			ns->status = Ns_Dead;
271			return;
272			}
273
274			/* data + end is where we start putting the new data. The last byte
275			* currently in use is actually data + end -1
276			*/
277
278			end = ns->outputbuffer.start + ns->outputbuffer.len;
279			/* The buffer is already in a wrapped state, so adjust end */
280			if (end >= SOCKETBUFSIZE)
281			end -= SOCKETBUFSIZE;
282	root	1.7
283	root	1.5	avail = SOCKETBUFSIZE - end;
284	elmex	1.1
285	root	1.5	/* We can all fit it behind the current data without wrapping */
286			if (avail >= len)
287	root	1.7	memcpy (ns->outputbuffer.data + end, buf, len);
288	root	1.5	else
289			{
290			memcpy (ns->outputbuffer.data + end, buf, avail);
291			memcpy (ns->outputbuffer.data, buf + avail, len - avail);
292	elmex	1.1	}
293	root	1.7
294	root	1.5	ns->outputbuffer.len += len;
295	elmex	1.1	#if 0
296	root	1.5	LOG (llevDebug, "Added %d to output buffer, total length now %d, start=%d\n", len, ns->outputbuffer.len, ns->outputbuffer.start);
297	elmex	1.1	#endif
298			}
299
300			/**
301			* Writes data to socket.
302			*
303			* When the socket is clear to write, and we have backlogged data, this
304			* is called to write it out.
305			*/
306	root	1.5	void
307			write_socket_buffer (NewSocket * ns)
308	elmex	1.1	{
309	root	1.5	int amt, max;
310	elmex	1.1
311	root	1.5	if (ns->outputbuffer.len == 0)
312			{
313			LOG (llevDebug, "write_socket_buffer called when there is no data, fd=%d\n", ns->fd);
314			return;
315	elmex	1.1	}
316
317	root	1.5	do
318			{
319			max = SOCKETBUFSIZE - ns->outputbuffer.start;
320			if (ns->outputbuffer.len < max)
321			max = ns->outputbuffer.len;
322	elmex	1.1
323	root	1.5	do
324			{
325			amt = write (ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
326			}
327			while ((amt < 0) && (errno == EINTR));
328	elmex	1.1
329	root	1.5	if (amt < 0)
330			{ /* We got an error */
331	elmex	1.1
332	root	1.5	if (errno != EWOULDBLOCK)
333			{
334			LOG (llevError, "New socket write failed (wsb) (%d: %s).\n", errno, strerror (errno));
335			ns->status = Ns_Dead;
336			return;
337	root	1.3	}
338	root	1.5	else
339			{ /* EWOULDBLOCK */
340			/* can't write it, so store it away. */
341			ns->can_write = 0;
342			return;
343	root	1.3	}
344			}
345	root	1.5	ns->outputbuffer.start += amt;
346			/* wrap back to start of buffer */
347			if (ns->outputbuffer.start == SOCKETBUFSIZE)
348			ns->outputbuffer.start = 0;
349			ns->outputbuffer.len -= amt;
350	elmex	1.1	#ifdef CS_LOGSTATS
351	root	1.5	cst_tot.obytes += amt;
352			cst_lst.obytes += amt;
353			#endif
354			}
355			while (ns->outputbuffer.len > 0);
356	elmex	1.1	}
357
358			/**
359			* This writes data to the socket. - It is very low level -
360			* all we try and do is write out the data to the socket
361			* provided (ns). buf is the data to write, len is the number
362			* of bytes to write. IT doesn't return anything - rather, it
363			* updates the ns structure if we get an error.
364			*/
365	root	1.5	void
366			Write_To_Socket (NewSocket * ns, char *buf, int len)
367	elmex	1.1	{
368	root	1.5	int amt = 0;
369			char *pos = buf;
370	elmex	1.1
371	root	1.5	if (ns->status == Ns_Dead \|\| !buf)
372			{
373			LOG (llevDebug, "Write_To_Socket called with dead socket\n");
374			return;
375	elmex	1.1	}
376	root	1.5
377			#ifndef __GNU__ /* This caused problems on Hurd */
378			if (!ns->can_write)
379			{
380			add_to_buffer (ns, buf, len);
381			return;
382	elmex	1.1	}
383			#endif
384	root	1.5	/* If we manage to write more than we wanted, take it as a bonus */
385			while (len > 0)
386			{
387	elmex	1.1
388	root	1.5	do
389			{
390			amt = write (ns->fd, pos, len);
391			}
392			while ((amt < 0) && (errno == EINTR));
393	elmex	1.1
394	root	1.5	if (amt < 0)
395			{ /* We got an error */
396			if (errno != EWOULDBLOCK)
397			{
398			LOG (llevError, "New socket write failed WTS (%d: %s).\n", /* ---WIN32 */
399			errno, strerror (errno));
400			ns->status = Ns_Dead;
401			return;
402	root	1.3	}
403	root	1.5	else
404			{ /* EWOULDBLOCK */
405			/* can't write it, so store it away. */
406			add_to_buffer (ns, pos, len);
407			ns->can_write = 0;
408			return;
409	root	1.3	}
410			}
411	root	1.5	/* amt gets set to 0 above in blocking code, so we do this as
412			* an else if to make sure we don't reprocess it.
413			*/
414			else if (amt == 0)
415			{
416			LOG (llevError, "Write_To_Socket: No data written out.\n");
417	root	1.3	}
418	root	1.5	len -= amt;
419			pos += amt;
420	elmex	1.1	#ifdef CS_LOGSTATS
421	root	1.5	cst_tot.obytes += amt;
422			cst_lst.obytes += amt;
423			#endif
424	elmex	1.1	}
425			}
426
427
428			/**
429			* Takes a string of data, and writes it out to the socket. A very handy
430			* shortcut function.
431			*/
432	root	1.5	void
433	root	1.11	cs_write_string (NewSocket ns, const char buf, int len)
434	elmex	1.1	{
435	root	1.5	SockList sl;
436	elmex	1.1
437	root	1.5	sl.len = len;
438			sl.buf = (unsigned char *) buf;
439			Send_With_Handling (ns, &sl);
440	elmex	1.1	}
441
442
443			/**
444			* Calls Write_To_Socket to send data to the client.
445			*
446			* The only difference in this function is that we take a SockList
447			*, and we prepend the length information.
448			*/
449	root	1.5	void
450	root	1.11	Send_With_Handling (NewSocket ns, SockList msg)
451	elmex	1.1	{
452	root	1.5	unsigned char sbuf[4];
453	elmex	1.1
454	root	1.5	if (ns->status == Ns_Dead \|\| !msg)
455			return;
456	elmex	1.1
457	root	1.5	if (msg->len >= MAXSOCKBUF)
458			{
459			LOG (llevError, "Trying to send a buffer beyond properly size, len =%d\n", msg->len);
460			/* Almost certainly we've overflowed a buffer, so quite now to make
461			* it easier to debug.
462			*/
463			abort ();
464			}
465			sbuf[0] = ((uint32) (msg->len) >> 8) & 0xFF;
466			sbuf[1] = ((uint32) (msg->len)) & 0xFF;
467			if (ns->status != Ns_Old)
468			Write_To_Socket (ns, (char *) sbuf, 2);
469			Write_To_Socket (ns, (char *) msg->buf, msg->len);
470	elmex	1.1	}
471
472			/**
473			* Takes a string of data, and writes it out to the socket. A very handy
474			* shortcut function.
475			*/
476	root	1.5	void
477	root	1.11	Write_String_To_Socket (NewSocket ns, char buf, int len)
478	elmex	1.1	{
479	root	1.5	SockList sl;
480	elmex	1.1
481	root	1.5	sl.len = len;
482			sl.buf = (unsigned char *) buf;
483			Send_With_Handling (ns, &sl);
484	elmex	1.1	}
485
486
487			/******************************************************************************
488			*
489			* statistics logging functions.
490			*
491			******************************************************************************/
492
493			#ifdef CS_LOGSTATS
494	root	1.5
495	elmex	1.1	/* cst_tot is for the life of the server, cst_last is for the last series of
496			* stats
497			*/
498			CS_Stats cst_tot, cst_lst;
499
500			/**
501			* Writes out the gathered stats. We clear cst_lst.
502			*/
503	root	1.5	void
504			write_cs_stats (void)
505	elmex	1.1	{
506	root	1.5	time_t now = time (NULL);
507	elmex	1.1
508	root	1.5	/* If no connections recently, don't both to log anything */
509			if (cst_lst.ibytes == 0 && cst_lst.obytes == 0)
510			return;
511
512			/* CSSTAT is put in so scripts can easily find the line */
513			LOG (llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
514			ctime (&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
515			now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes, cst_lst.max_conn, now - cst_lst.time_start);
516			cst_lst.ibytes = 0;
517			cst_lst.obytes = 0;
518			cst_lst.max_conn = socket_info.nconns;
519			cst_lst.time_start = now;
520	elmex	1.1	}
521			#endif
522	root	1.9