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.
 */

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_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;

    /* 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, 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, 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_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, (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:	1.1
Committed:	Sun Aug 13 17:16:06 2006 UTC (17 years, 10 months ago) by elmex
Content type:	text/plain
Branch:	MAIN
Log Message:	Made server compile with C++. Removed cfanim plugin and crossedit. C++ here we come.
#	User	Rev	Content
1	elmex	1.1
2			/*
3			* static char *rcsid_sockets_c =
4			* "$Id$";
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 Socket_Flush (NewSocket *ns)
61			{
62			#ifdef __linux__
63			// check time of last ack, and, if too old, kill connection
64			struct tcp_info tcpi;
65			socklen_t len = sizeof (tcpi);
66
67			if (!getsockopt (ns->fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
68			{
69			unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;
70
71			if (tcpi.tcpi_unacked
72			&& 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			val = 0; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
83			val = 1; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
84			#endif
85			}
86
87			/***********************************************************************
88			*
89			* SockList functions/utilities
90			*
91			**********************************************************************/
92
93			void SockList_Init(SockList *sl)
94			{
95			sl->len=0;
96			sl->buf=NULL;
97			}
98
99			void SockList_AddChar(SockList *sl, char c)
100			{
101			sl->buf[sl->len]=c;
102			sl->len++;
103			}
104
105			void SockList_AddShort(SockList *sl, uint16 data)
106			{
107			sl->buf[sl->len++]= (data>>8)&0xff;
108			sl->buf[sl->len++] = data & 0xff;
109			}
110
111
112			void SockList_AddInt(SockList *sl, uint32 data)
113			{
114			sl->buf[sl->len++]= (data>>24)&0xff;
115			sl->buf[sl->len++]= (data>>16)&0xff;
116			sl->buf[sl->len++]= (data>>8)&0xff;
117			sl->buf[sl->len++] = data & 0xff;
118			}
119
120			void SockList_AddInt64(SockList *sl, uint64 data)
121			{
122			sl->buf[sl->len++]= ( char )( (data>>56)&0xff );
123			sl->buf[sl->len++]= ( char )( (data>>48)&0xff );
124			sl->buf[sl->len++]= ( char )( (data>>40)&0xff );
125			sl->buf[sl->len++]= ( char )( (data>>32)&0xff );
126
127			sl->buf[sl->len++]= ( char )( (data>>24)&0xff );
128			sl->buf[sl->len++]= ( char )( (data>>16)&0xff );
129			sl->buf[sl->len++]= ( char )( (data>>8)&0xff );
130			sl->buf[sl->len++] =( char )( data & 0xff );
131			}
132
133			/* Basically does the reverse of SockList_AddInt, but on
134			* strings instead. Same for the GetShort, but for 16 bits.
135			*/
136			int GetInt_String(unsigned char *data)
137			{
138			return ((data[0]<<24) + (data[1]<<16) + (data[2]<<8) + data[3]);
139			}
140
141			short GetShort_String(unsigned char *data) {
142			return ((data[0]<<8)+data[1]);
143			}
144
145			/******************************************************************************
146			*
147			* Start of read routines.
148			*
149			******************************************************************************/
150
151			/**
152			* This reads from fd and puts the data in sl. We return true if we think
153			* we have a full packet, 0 if we have a partial packet. The only processing
154			* we do is remove the intial size value. len (As passed) is the size of the
155			* buffer allocated in the socklist. We make the assumption the buffer is
156			* at least 2 bytes long.
157			*/
158
159			int SockList_ReadPacket(int fd, SockList *sl, int len)
160			{
161			int stat,toread;
162
163			/* Sanity check - shouldn't happen */
164			if (sl->len < 0) {
165			abort();
166			}
167			/* We already have a partial packet */
168			if (sl->len<2) {
169			#ifdef WIN32 /* **WIN32 SockList_ReadPacket: change read() to recv() /
170
171			stat=recv(fd, sl->buf + sl->len, 2-sl->len,0);
172
173			#else
174			do {
175			stat=read(fd, sl->buf + sl->len, 2-sl->len);
176			} while ((stat==-1) && (errno==EINTR));
177			#endif
178			if (stat<0) {
179			/* In non blocking mode, EAGAIN is set when there is no
180			* data available.
181			*/
182			#ifdef WIN32 /* **WIN32 SockList_ReadPacket: error handling for win32 /
183			if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
184			if(WSAGetLastError() == WSAECONNRESET)
185			LOG(llevDebug,"Connection closed by client\n");
186			else
187			{
188			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
189			}
190			return -1; /* kick this user! */
191			}
192			#else
193			if (errno != EAGAIN && errno !=EWOULDBLOCK) {
194			LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
195			}
196			#endif
197			return 0; /Error /
198			}
199			if (stat==0) return -1;
200			sl->len += stat;
201			#ifdef CS_LOGSTATS
202			cst_tot.ibytes += stat;
203			cst_lst.ibytes += stat;
204			#endif
205			if (stat<2) return 0; /* Still don't have a full packet */
206			}
207			/* Figure out how much more data we need to read. Add 2 from the
208			* end of this - size header information is not included.
209			*/
210			toread = 2+(sl->buf[0] << 8) + sl->buf[1] - sl->len;
211			if ((toread + sl->len) >= len) {
212			LOG(llevError,"SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n",
213			toread + sl->len, len);
214			/* Quick hack in case for 'oldsocketmode' input. If we are
215			* closing the socket anyways, then reading this extra 100 bytes
216			* shouldn't hurt.
217			*/
218			#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
219			recv(fd, sl->buf+2, 100, 0);
220			#else
221			read(fd, sl->buf+2, 100);
222			#endif /* end win32 */
223
224			/* return error so the socket is closed */
225			return -1;
226			}
227			do {
228			#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
229			stat = recv(fd, sl->buf+ sl->len, toread, 0);
230			#else
231			do {
232			stat = read(fd, sl->buf+ sl->len, toread);
233			} while ((stat<0) && (errno==EINTR));
234			#endif
235			if (stat<0) {
236
237			#ifdef WIN32 /* **win32 SockList_ReadPacket: change error handling for win32 /
238			if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
239			if(WSAGetLastError() == WSAECONNRESET)
240			LOG(llevDebug,"Connection closed by client\n");
241			else
242			{
243			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
244			}
245			return -1; /* kick this user! */
246			}
247			#else
248			if (errno != EAGAIN && errno !=EWOULDBLOCK) {
249			LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
250			}
251			#endif
252			return 0; /Error /
253			}
254			if (stat==0) return -1;
255			sl->len += stat;
256			#ifdef CS_LOGSTATS
257			cst_tot.ibytes += stat;
258			cst_lst.ibytes += stat;
259			#endif
260			toread -= stat;
261			if (toread==0) return 1;
262			if (toread < 0) {
263			LOG(llevError,"SockList_ReadPacket: Read more bytes than desired.\n");
264			return 1;
265			}
266			} while (toread>0);
267			return 0;
268			}
269
270			/*******************************************************************************
271			*
272			* Start of write related routines.
273			*
274			******************************************************************************/
275
276			/**
277			* Adds data to a socket buffer for whatever reason.
278			*
279			* ns is the socket we are adding the data to, buf is the start of the
280			* data, and len is the number of bytes to add.
281			*/
282
283			static void add_to_buffer(NewSocket ns, char buf, int len)
284			{
285			int avail, end;
286
287			if ((len+ns->outputbuffer.len)>SOCKETBUFSIZE) {
288			LOG(llevDebug,"Socket on fd %d has overrun internal buffer - marking as dead\n",
289			ns->fd);
290			ns->status = Ns_Dead;
291			return;
292			}
293
294			/* data + end is where we start putting the new data. The last byte
295			* currently in use is actually data + end -1
296			*/
297
298			end=ns->outputbuffer.start + ns->outputbuffer.len;
299			/* The buffer is already in a wrapped state, so adjust end */
300			if (end>=SOCKETBUFSIZE) end-=SOCKETBUFSIZE;
301			avail=SOCKETBUFSIZE - end;
302
303			/* We can all fit it behind the current data without wrapping */
304			if (avail >=len ) {
305			memcpy(ns->outputbuffer.data + end, buf, len);
306			}
307			else {
308			memcpy(ns->outputbuffer.data + end, buf, avail);
309			memcpy(ns->outputbuffer.data, buf+avail, len-avail);
310			}
311			ns->outputbuffer.len += len;
312			#if 0
313			LOG(llevDebug,"Added %d to output buffer, total length now %d, start=%d\n", len,
314			ns->outputbuffer.len, ns->outputbuffer.start);
315			#endif
316			}
317
318			/**
319			* Writes data to socket.
320			*
321			* When the socket is clear to write, and we have backlogged data, this
322			* is called to write it out.
323			*/
324			void write_socket_buffer(NewSocket *ns)
325			{
326			int amt, max;
327
328			if (ns->outputbuffer.len==0) {
329			LOG(llevDebug,"write_socket_buffer called when there is no data, fd=%d\n",
330			ns->fd);
331			return;
332			}
333
334			do {
335			max = SOCKETBUFSIZE - ns->outputbuffer.start;
336			if (ns->outputbuffer.len<max) max = ns->outputbuffer.len;
337
338			#ifdef WIN32 /* **win32 write_socket_buffer: change write() to send() /
339			amt=send(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max,0);
340			#else
341			do {
342			amt=write(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
343			} while ((amt<0) && (errno==EINTR));
344			#endif
345
346			if (amt < 0) { /* We got an error */
347
348			#ifdef WIN32 /* **win32 write_socket_buffer: change error handling /
349			if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
350			LOG(llevError,"New socket write failed (wsb) (%d).\n", WSAGetLastError());
351			#else
352			if (errno !=EWOULDBLOCK) {
353			LOG(llevError,"New socket write failed (wsb) (%d: %s).\n",
354			errno, strerror_local(errno));
355			#endif
356			ns->status=Ns_Dead;
357			return;
358			}
359			else { /* EWOULDBLOCK */
360			/* can't write it, so store it away. */
361			ns->can_write=0;
362			return;
363			}
364			}
365			ns->outputbuffer.start += amt;
366			/* wrap back to start of buffer */
367			if (ns->outputbuffer.start==SOCKETBUFSIZE) ns->outputbuffer.start=0;
368			ns->outputbuffer.len -= amt;
369			#ifdef CS_LOGSTATS
370			cst_tot.obytes += amt;
371			cst_lst.obytes += amt;
372			#endif
373			} while (ns->outputbuffer.len>0);
374			}
375
376			/**
377			* This writes data to the socket. - It is very low level -
378			* all we try and do is write out the data to the socket
379			* provided (ns). buf is the data to write, len is the number
380			* of bytes to write. IT doesn't return anything - rather, it
381			* updates the ns structure if we get an error.
382			*/
383			void Write_To_Socket(NewSocket ns, char buf, int len)
384			{
385			int amt=0;
386			char *pos=buf;
387
388			if (ns->status == Ns_Dead \|\| !buf) {
389			LOG(llevDebug,"Write_To_Socket called with dead socket\n");
390			return;
391			}
392
393			#ifndef __GNU__ /* This caused problems on Hurd */
394			if (!ns->can_write) {
395			add_to_buffer(ns, buf, len);
396			return;
397			}
398			#endif
399			/* If we manage to write more than we wanted, take it as a bonus */
400			while (len>0) {
401
402			#ifdef WIN32 /* **win32 Write_To_Socket: change write() to send() /
403			amt=send(ns->fd, pos, len,0);
404			#else
405			do {
406			amt=write(ns->fd, pos, len);
407			} while ((amt<0) && (errno==EINTR));
408			#endif
409
410			if (amt < 0) { /* We got an error */
411			#ifdef WIN32 /* **win32 Write_To_Socket: change error handling /
412			if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
413			LOG(llevError,"New socket write failed WTS (%d).\n",WSAGetLastError());
414			#else
415			if (errno !=EWOULDBLOCK) {
416			LOG(llevError,"New socket write failed WTS (%d: %s).\n", /* ---WIN32 */
417			errno, strerror_local(errno));
418			#endif
419			ns->status=Ns_Dead;
420			return;
421			}
422			else { /* EWOULDBLOCK */
423			/* can't write it, so store it away. */
424			add_to_buffer(ns, pos, len);
425			ns->can_write=0;
426			return;
427			}
428			}
429			/* amt gets set to 0 above in blocking code, so we do this as
430			* an else if to make sure we don't reprocess it.
431			*/
432			else if (amt==0) {
433			LOG(llevError,"Write_To_Socket: No data written out.\n");
434			}
435			len -= amt;
436			pos += amt;
437			#ifdef CS_LOGSTATS
438			cst_tot.obytes += amt;
439			cst_lst.obytes += amt;
440			#endif
441			}
442			}
443
444
445			/**
446			* Takes a string of data, and writes it out to the socket. A very handy
447			* shortcut function.
448			*/
449			void cs_write_string(NewSocket ns, const char buf, int len)
450			{
451			SockList sl;
452
453			sl.len = len;
454			sl.buf = (unsigned char*)buf;
455			Send_With_Handling(ns, &sl);
456			}
457
458
459			/**
460			* Calls Write_To_Socket to send data to the client.
461			*
462			* The only difference in this function is that we take a SockList
463			*, and we prepend the length information.
464			*/
465			void Send_With_Handling(NewSocket ns,SockList msg)
466			{
467			unsigned char sbuf[4];
468
469			if (ns->status == Ns_Dead \|\| !msg)
470			return;
471
472			if (msg->len >= MAXSOCKBUF) {
473			LOG(llevError,"Trying to send a buffer beyond properly size, len =%d\n",
474			msg->len);
475			/* Almost certainly we've overflowed a buffer, so quite now to make
476			* it easier to debug.
477			*/
478			abort();
479			}
480			sbuf[0] = ((uint32)(msg->len) >> 8) & 0xFF;
481			sbuf[1] = ((uint32)(msg->len)) & 0xFF;
482			if (ns->status != Ns_Old)
483			Write_To_Socket(ns, (char *) sbuf, 2);
484			Write_To_Socket(ns, (char*)msg->buf, msg->len);
485			}
486
487			/**
488			* Takes a string of data, and writes it out to the socket. A very handy
489			* shortcut function.
490			*/
491			void Write_String_To_Socket(NewSocket ns, char buf, int len)
492			{
493			SockList sl;
494
495			sl.len = len;
496			sl.buf = (unsigned char*) buf;
497			Send_With_Handling(ns, &sl);
498			}
499
500
501			/******************************************************************************
502			*
503			* statistics logging functions.
504			*
505			******************************************************************************/
506
507			#ifdef CS_LOGSTATS
508			/* cst_tot is for the life of the server, cst_last is for the last series of
509			* stats
510			*/
511			CS_Stats cst_tot, cst_lst;
512
513			/**
514			* Writes out the gathered stats. We clear cst_lst.
515			*/
516			void write_cs_stats(void)
517			{
518			time_t now=time(NULL);
519
520			/* If no connections recently, don't both to log anything */
521			if (cst_lst.ibytes==0 && cst_lst.obytes==0) return;
522
523			/* CSSTAT is put in so scripts can easily find the line */
524			LOG(llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
525			ctime(&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
526			now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes,
527			cst_lst.max_conn, now - cst_lst.time_start);
528			cst_lst.ibytes=0;
529			cst_lst.obytes=0;
530			cst_lst.max_conn=socket_info.nconns;
531			cst_lst.time_start=now;
532			}
533			#endif