server/socket/lowlevel.c


/*
 * static char *rcsid_sockets_c =
 *    "$Id$";
 */

/*
    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.
 */

#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... (actually, 20s after the last data was sent
#define SOCKET_TIMEOUT 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_TIMEOUT * TCP_HZ < diff && diff < 0x80000000UL)
        {
          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_AddChar(SockList *sl, char c)
{
    sl->buf[sl->len]=c;
    sl->len++;
}

void SockList_AddShort(SockList *sl, uint16 data)
{
    sl->buf[sl->len++]= (data>>8)&0xff;
    sl->buf[sl->len++] = data & 0xff;
}


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;
    extern int errno;

    /* 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_local(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_local(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, unsigned 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_local(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, unsigned char *buf, int len)
{
    int amt=0;
    unsigned 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_local(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, sbuf, 2);
    Write_To_Socket(ns, 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 = (uint8*)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:	1.4
Committed:	Sat Jun 10 06:54:46 2006 UTC (20 years, 4 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.3:	+8 -7 lines
Log Message:	tweaked connection timeout to be less sensitive, maybe this helps Ronwe
#	User	Rev	Content
1	root	1.1
2			/*
3			* static char *rcsid_sockets_c =
4	root	1.2	* "$Id$";
5	root	1.1	*/
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			#include <global.h>
42			#include <newclient.h>
43			#include <sproto.h>
44
45	root	1.2	#ifdef __linux__
46			# include <sys/types.h>
47			# include <sys/socket.h>
48			# include <netinet/in.h>
49	root	1.3	# define TCP_HZ 1000 // sorry...
50	root	1.2	# include <netinet/tcp.h>
51			#endif
52
53	root	1.3	// use a really low timeout, as it doesn't cost any bandwidth, and you can
54			// easily die in 20 seconds... (actually, 20s after the last data was sent
55			#define SOCKET_TIMEOUT 20
56
57	root	1.2	void Socket_Flush (NewSocket *ns)
58			{
59			#ifdef __linux__
60	root	1.3	// check time of last ack, and, if too old, kill connection
61			struct tcp_info tcpi;
62			socklen_t len = sizeof (tcpi);
63	root	1.4
64	root	1.3	if (!getsockopt (ns->fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
65			{
66			unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;
67
68	root	1.4	if (tcpi.tcpi_unacked && SOCKET_TIMEOUT * TCP_HZ < diff && diff < 0x80000000UL)
69	root	1.3	{
70	root	1.4	LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd,
71			(unsigned)tcpi.tcpi_last_ack_recv, (unsigned)tcpi.tcpi_last_data_sent, (unsigned)tcpi.tcpi_unacked);
72	root	1.3	ns->status = Ns_Dead;
73			}
74			}
75	root	1.4
76			int val;
77			val = 0; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
78			val = 1; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
79	root	1.2	#endif
80			}
81
82	root	1.1	/***********************************************************************
83			*
84			* SockList functions/utilities
85			*
86			**********************************************************************/
87
88			void SockList_Init(SockList *sl)
89			{
90			sl->len=0;
91			sl->buf=NULL;
92			}
93
94			void SockList_AddChar(SockList *sl, char c)
95			{
96			sl->buf[sl->len]=c;
97			sl->len++;
98			}
99
100			void SockList_AddShort(SockList *sl, uint16 data)
101			{
102			sl->buf[sl->len++]= (data>>8)&0xff;
103			sl->buf[sl->len++] = data & 0xff;
104			}
105
106
107			void SockList_AddInt(SockList *sl, uint32 data)
108			{
109			sl->buf[sl->len++]= (data>>24)&0xff;
110			sl->buf[sl->len++]= (data>>16)&0xff;
111			sl->buf[sl->len++]= (data>>8)&0xff;
112			sl->buf[sl->len++] = data & 0xff;
113			}
114
115			void SockList_AddInt64(SockList *sl, uint64 data)
116			{
117			sl->buf[sl->len++]= ( char )( (data>>56)&0xff );
118			sl->buf[sl->len++]= ( char )( (data>>48)&0xff );
119			sl->buf[sl->len++]= ( char )( (data>>40)&0xff );
120			sl->buf[sl->len++]= ( char )( (data>>32)&0xff );
121
122			sl->buf[sl->len++]= ( char )( (data>>24)&0xff );
123			sl->buf[sl->len++]= ( char )( (data>>16)&0xff );
124			sl->buf[sl->len++]= ( char )( (data>>8)&0xff );
125			sl->buf[sl->len++] =( char )( data & 0xff );
126			}
127
128			/* Basically does the reverse of SockList_AddInt, but on
129			* strings instead. Same for the GetShort, but for 16 bits.
130			*/
131			int GetInt_String(unsigned char *data)
132			{
133			return ((data[0]<<24) + (data[1]<<16) + (data[2]<<8) + data[3]);
134			}
135
136			short GetShort_String(unsigned char *data) {
137			return ((data[0]<<8)+data[1]);
138			}
139
140			/******************************************************************************
141			*
142			* Start of read routines.
143			*
144			******************************************************************************/
145
146			/**
147			* This reads from fd and puts the data in sl. We return true if we think
148			* we have a full packet, 0 if we have a partial packet. The only processing
149			* we do is remove the intial size value. len (As passed) is the size of the
150			* buffer allocated in the socklist. We make the assumption the buffer is
151			* at least 2 bytes long.
152			*/
153
154			int SockList_ReadPacket(int fd, SockList *sl, int len)
155			{
156			int stat,toread;
157			extern int errno;
158
159			/* Sanity check - shouldn't happen */
160			if (sl->len < 0) {
161			abort();
162			}
163			/* We already have a partial packet */
164			if (sl->len<2) {
165			#ifdef WIN32 /* **WIN32 SockList_ReadPacket: change read() to recv() /
166
167			stat=recv(fd, sl->buf + sl->len, 2-sl->len,0);
168
169			#else
170			do {
171			stat=read(fd, sl->buf + sl->len, 2-sl->len);
172			} while ((stat==-1) && (errno==EINTR));
173			#endif
174			if (stat<0) {
175			/* In non blocking mode, EAGAIN is set when there is no
176			* data available.
177			*/
178			#ifdef WIN32 /* **WIN32 SockList_ReadPacket: error handling for win32 /
179			if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
180			if(WSAGetLastError() == WSAECONNRESET)
181			LOG(llevDebug,"Connection closed by client\n");
182			else
183			{
184			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
185			}
186			return -1; /* kick this user! */
187			}
188			#else
189			if (errno != EAGAIN && errno !=EWOULDBLOCK) {
190			LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
191			}
192			#endif
193			return 0; /Error /
194			}
195			if (stat==0) return -1;
196			sl->len += stat;
197			#ifdef CS_LOGSTATS
198			cst_tot.ibytes += stat;
199			cst_lst.ibytes += stat;
200			#endif
201			if (stat<2) return 0; /* Still don't have a full packet */
202			}
203			/* Figure out how much more data we need to read. Add 2 from the
204			* end of this - size header information is not included.
205			*/
206			toread = 2+(sl->buf[0] << 8) + sl->buf[1] - sl->len;
207			if ((toread + sl->len) >= len) {
208			LOG(llevError,"SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n",
209			toread + sl->len, len);
210			/* Quick hack in case for 'oldsocketmode' input. If we are
211			* closing the socket anyways, then reading this extra 100 bytes
212			* shouldn't hurt.
213			*/
214			#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
215			recv(fd, sl->buf+2, 100, 0);
216			#else
217			read(fd, sl->buf+2, 100);
218			#endif /* end win32 */
219
220			/* return error so the socket is closed */
221			return -1;
222			}
223			do {
224			#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
225			stat = recv(fd, sl->buf+ sl->len, toread, 0);
226			#else
227			do {
228			stat = read(fd, sl->buf+ sl->len, toread);
229			} while ((stat<0) && (errno==EINTR));
230			#endif
231			if (stat<0) {
232
233			#ifdef WIN32 /* **win32 SockList_ReadPacket: change error handling for win32 /
234			if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
235			if(WSAGetLastError() == WSAECONNRESET)
236			LOG(llevDebug,"Connection closed by client\n");
237			else
238			{
239			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
240			}
241			return -1; /* kick this user! */
242			}
243			#else
244			if (errno != EAGAIN && errno !=EWOULDBLOCK) {
245			LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
246			}
247			#endif
248			return 0; /Error /
249			}
250			if (stat==0) return -1;
251			sl->len += stat;
252			#ifdef CS_LOGSTATS
253			cst_tot.ibytes += stat;
254			cst_lst.ibytes += stat;
255			#endif
256			toread -= stat;
257			if (toread==0) return 1;
258			if (toread < 0) {
259			LOG(llevError,"SockList_ReadPacket: Read more bytes than desired.\n");
260			return 1;
261			}
262			} while (toread>0);
263			return 0;
264			}
265
266			/*******************************************************************************
267			*
268			* Start of write related routines.
269			*
270			******************************************************************************/
271
272			/**
273			* Adds data to a socket buffer for whatever reason.
274			*
275			* ns is the socket we are adding the data to, buf is the start of the
276			* data, and len is the number of bytes to add.
277			*/
278
279			static void add_to_buffer(NewSocket ns, unsigned char buf, int len)
280			{
281			int avail, end;
282
283			if ((len+ns->outputbuffer.len)>SOCKETBUFSIZE) {
284			LOG(llevDebug,"Socket on fd %d has overrun internal buffer - marking as dead\n",
285			ns->fd);
286			ns->status = Ns_Dead;
287			return;
288			}
289
290			/* data + end is where we start putting the new data. The last byte
291			* currently in use is actually data + end -1
292			*/
293
294			end=ns->outputbuffer.start + ns->outputbuffer.len;
295			/* The buffer is already in a wrapped state, so adjust end */
296			if (end>=SOCKETBUFSIZE) end-=SOCKETBUFSIZE;
297			avail=SOCKETBUFSIZE - end;
298
299			/* We can all fit it behind the current data without wrapping */
300			if (avail >=len ) {
301			memcpy(ns->outputbuffer.data + end, buf, len);
302			}
303			else {
304			memcpy(ns->outputbuffer.data + end, buf, avail);
305			memcpy(ns->outputbuffer.data, buf+avail, len-avail);
306			}
307			ns->outputbuffer.len += len;
308			#if 0
309			LOG(llevDebug,"Added %d to output buffer, total length now %d, start=%d\n", len,
310			ns->outputbuffer.len, ns->outputbuffer.start);
311			#endif
312			}
313
314			/**
315			* Writes data to socket.
316			*
317			* When the socket is clear to write, and we have backlogged data, this
318			* is called to write it out.
319			*/
320			void write_socket_buffer(NewSocket *ns)
321			{
322			int amt, max;
323
324			if (ns->outputbuffer.len==0) {
325			LOG(llevDebug,"write_socket_buffer called when there is no data, fd=%d\n",
326			ns->fd);
327			return;
328			}
329
330			do {
331			max = SOCKETBUFSIZE - ns->outputbuffer.start;
332			if (ns->outputbuffer.len<max) max = ns->outputbuffer.len;
333
334			#ifdef WIN32 /* **win32 write_socket_buffer: change write() to send() /
335			amt=send(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max,0);
336			#else
337			do {
338			amt=write(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
339			} while ((amt<0) && (errno==EINTR));
340			#endif
341
342			if (amt < 0) { /* We got an error */
343
344			#ifdef WIN32 /* **win32 write_socket_buffer: change error handling /
345			if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
346			LOG(llevError,"New socket write failed (wsb) (%d).\n", WSAGetLastError());
347			#else
348			if (errno !=EWOULDBLOCK) {
349			LOG(llevError,"New socket write failed (wsb) (%d: %s).\n",
350			errno, strerror_local(errno));
351			#endif
352			ns->status=Ns_Dead;
353			return;
354			}
355			else { /* EWOULDBLOCK */
356			/* can't write it, so store it away. */
357			ns->can_write=0;
358			return;
359			}
360			}
361			ns->outputbuffer.start += amt;
362			/* wrap back to start of buffer */
363			if (ns->outputbuffer.start==SOCKETBUFSIZE) ns->outputbuffer.start=0;
364			ns->outputbuffer.len -= amt;
365			#ifdef CS_LOGSTATS
366			cst_tot.obytes += amt;
367			cst_lst.obytes += amt;
368			#endif
369			} while (ns->outputbuffer.len>0);
370			}
371
372			/**
373			* This writes data to the socket. - It is very low level -
374			* all we try and do is write out the data to the socket
375			* provided (ns). buf is the data to write, len is the number
376			* of bytes to write. IT doesn't return anything - rather, it
377			* updates the ns structure if we get an error.
378			*/
379			void Write_To_Socket(NewSocket ns, unsigned char buf, int len)
380			{
381			int amt=0;
382			unsigned char *pos=buf;
383
384			if (ns->status == Ns_Dead \|\| !buf) {
385			LOG(llevDebug,"Write_To_Socket called with dead socket\n");
386			return;
387			}
388
389			#ifndef __GNU__ /* This caused problems on Hurd */
390			if (!ns->can_write) {
391			add_to_buffer(ns, buf, len);
392			return;
393			}
394			#endif
395			/* If we manage to write more than we wanted, take it as a bonus */
396			while (len>0) {
397
398			#ifdef WIN32 /* **win32 Write_To_Socket: change write() to send() /
399			amt=send(ns->fd, pos, len,0);
400			#else
401			do {
402			amt=write(ns->fd, pos, len);
403			} while ((amt<0) && (errno==EINTR));
404			#endif
405
406			if (amt < 0) { /* We got an error */
407			#ifdef WIN32 /* **win32 Write_To_Socket: change error handling /
408			if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
409			LOG(llevError,"New socket write failed WTS (%d).\n",WSAGetLastError());
410			#else
411			if (errno !=EWOULDBLOCK) {
412			LOG(llevError,"New socket write failed WTS (%d: %s).\n", /* ---WIN32 */
413			errno, strerror_local(errno));
414			#endif
415			ns->status=Ns_Dead;
416			return;
417			}
418			else { /* EWOULDBLOCK */
419			/* can't write it, so store it away. */
420			add_to_buffer(ns, pos, len);
421			ns->can_write=0;
422			return;
423			}
424			}
425			/* amt gets set to 0 above in blocking code, so we do this as
426			* an else if to make sure we don't reprocess it.
427			*/
428			else if (amt==0) {
429			LOG(llevError,"Write_To_Socket: No data written out.\n");
430			}
431			len -= amt;
432			pos += amt;
433			#ifdef CS_LOGSTATS
434			cst_tot.obytes += amt;
435			cst_lst.obytes += amt;
436			#endif
437			}
438			}
439
440
441			/**
442			* Takes a string of data, and writes it out to the socket. A very handy
443			* shortcut function.
444			*/
445			void cs_write_string(NewSocket ns, const char buf, int len)
446			{
447			SockList sl;
448
449			sl.len = len;
450			sl.buf = (unsigned char*)buf;
451			Send_With_Handling(ns, &sl);
452			}
453
454
455			/**
456			* Calls Write_To_Socket to send data to the client.
457			*
458			* The only difference in this function is that we take a SockList
459			*, and we prepend the length information.
460			*/
461			void Send_With_Handling(NewSocket ns,SockList msg)
462			{
463			unsigned char sbuf[4];
464
465			if (ns->status == Ns_Dead \|\| !msg)
466			return;
467
468			if (msg->len >= MAXSOCKBUF) {
469			LOG(llevError,"Trying to send a buffer beyond properly size, len =%d\n",
470			msg->len);
471			/* Almost certainly we've overflowed a buffer, so quite now to make
472			* it easier to debug.
473			*/
474			abort();
475			}
476			sbuf[0] = ((uint32)(msg->len) >> 8) & 0xFF;
477			sbuf[1] = ((uint32)(msg->len)) & 0xFF;
478			if (ns->status != Ns_Old)
479			Write_To_Socket(ns, sbuf, 2);
480			Write_To_Socket(ns, msg->buf, msg->len);
481			}
482
483			/**
484			* Takes a string of data, and writes it out to the socket. A very handy
485			* shortcut function.
486			*/
487			void Write_String_To_Socket(NewSocket ns, char buf, int len)
488			{
489			SockList sl;
490
491			sl.len = len;
492			sl.buf = (uint8*)buf;
493			Send_With_Handling(ns, &sl);
494			}
495
496
497			/******************************************************************************
498			*
499			* statistics logging functions.
500			*
501			******************************************************************************/
502
503			#ifdef CS_LOGSTATS
504			/* cst_tot is for the life of the server, cst_last is for the last series of
505			* stats
506			*/
507			CS_Stats cst_tot, cst_lst;
508
509			/**
510			* Writes out the gathered stats. We clear cst_lst.
511			*/
512			void write_cs_stats(void)
513			{
514			time_t now=time(NULL);
515
516			/* If no connections recently, don't both to log anything */
517			if (cst_lst.ibytes==0 && cst_lst.obytes==0) return;
518
519			/* CSSTAT is put in so scripts can easily find the line */
520			LOG(llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
521			ctime(&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
522			now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes,
523			cst_lst.max_conn, now - cst_lst.time_start);
524			cst_lst.ibytes=0;
525			cst_lst.obytes=0;
526			cst_lst.max_conn=socket_info.nconns;
527			cst_lst.time_start=now;
528			}
529			#endif