server/socket/lowlevel.C


/*
 * static char *rcsid_sockets_c =
 *    "$Id: lowlevel.C,v 1.3 2006-08-29 08:01:38 root Exp $";
 */

/*
    CrossFire, A Multiplayer game for X-windows

    Copyright (C) 1992 Frank Tore Johansen

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

    The author can be reached via e-mail to mark@pyramid.com
*/

/**
 * \file
 * Low-level socket-related functions.
 *
 * \date 2003-12-02
 *
 * Contains some base functions that both the client and server
 * can use.  As such, depending what we are being compiled for will
 * determine what we can include.  the client is designed have
 * CFCLIENT defined as part of its compile flags.
 */

using namespace std;

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

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

// use a really low timeout, as it doesn't cost any bandwidth, and you can
// easily die in 20 seconds...
#define SOCKET_TIMEOUT1 10
#define SOCKET_TIMEOUT2 20

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

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

      if (tcpi.tcpi_unacked
          && SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL // ack delayed for 20s
          && SOCKET_TIMEOUT2 * TCP_HZ < tcpi.tcpi_last_data_sent)   // no data sent for 10s
        {
          LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd,
               (unsigned)tcpi.tcpi_last_ack_recv, (unsigned)tcpi.tcpi_last_data_sent, (unsigned)tcpi.tcpi_unacked);
          ns->status = Ns_Dead;
        }
    }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

/*******************************************************************************
 *
 * Start of write related routines.
 *
 ******************************************************************************/

/**
 * Adds data to a socket buffer for whatever reason.
 *
 * ns is the socket we are adding the data to, buf is the start of the
 * data, and len is the number of bytes to add.
 */

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

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

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

    end=ns->outputbuffer.start + ns->outputbuffer.len;
    /* The buffer is already in a wrapped state, so adjust end */
    if (end>=SOCKETBUFSIZE) end-=SOCKETBUFSIZE;
    avail=SOCKETBUFSIZE - end;

    /* We can all fit it behind the current data without wrapping */
    if (avail >=len ) {
        memcpy(ns->outputbuffer.data + end, buf, len);
    }
    else {
        memcpy(ns->outputbuffer.data + end, buf, avail);
        memcpy(ns->outputbuffer.data, buf+avail, len-avail);
    }
    ns->outputbuffer.len += len;
#if 0
    LOG(llevDebug,"Added %d to output buffer, total length now %d, start=%d\n", len,
        ns->outputbuffer.len, ns->outputbuffer.start);
#endif
}

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

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

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

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

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

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

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

    if (ns->status == Ns_Dead || !buf) {
        LOG(llevDebug,"Write_To_Socket called with dead socket\n");
        return;
    }
 
#ifndef __GNU__ /* This caused problems on Hurd */
    if (!ns->can_write) {
        add_to_buffer(ns, buf, len);
        return;
    }
#endif
    /* If we manage to write more than we wanted, take it as a bonus */
    while (len>0) {

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

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


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

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


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

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

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

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

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


/******************************************************************************
 *
 * statistics logging functions.
 *
 ******************************************************************************/

#ifdef CS_LOGSTATS
/* cst_tot is for the life of the server, cst_last is for the last series of
 * stats
 */
CS_Stats cst_tot, cst_lst;

/**
 * Writes out the gathered stats.  We clear cst_lst.
 */
void write_cs_stats(void)
{
    time_t now=time(NULL);

    /* If no connections recently, don't both to log anything */
    if (cst_lst.ibytes==0 && cst_lst.obytes==0) return;

    /* CSSTAT is put in so scripts can easily find the line */
    LOG(llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
        ctime(&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
        now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes,
        cst_lst.max_conn, now - cst_lst.time_start);
    cst_lst.ibytes=0;
    cst_lst.obytes=0;
    cst_lst.max_conn=socket_info.nconns;
    cst_lst.time_start=now;
}
#endif
Revision:	1.4
Committed:	Wed Aug 30 16:30:37 2006 UTC (17 years, 8 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.3:	+5 -5 lines
Log Message:	remove compression support, intiialise perl earlier etc. etc.
#	User	Rev	Content
1	elmex	1.1
2			/*
3			* static char *rcsid_sockets_c =
4	root	1.4	* "$Id: lowlevel.C,v 1.3 2006-08-29 08:01:38 root Exp $";
5	elmex	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			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	root	1.3	LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd,
76	elmex	1.1	(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_AddInt(SockList *sl, uint32 data)
100			{
101			sl->buf[sl->len++]= (data>>24)&0xff;
102			sl->buf[sl->len++]= (data>>16)&0xff;
103			sl->buf[sl->len++]= (data>>8)&0xff;
104			sl->buf[sl->len++] = data & 0xff;
105			}
106
107			void SockList_AddInt64(SockList *sl, uint64 data)
108			{
109			sl->buf[sl->len++]= ( char )( (data>>56)&0xff );
110			sl->buf[sl->len++]= ( char )( (data>>48)&0xff );
111			sl->buf[sl->len++]= ( char )( (data>>40)&0xff );
112			sl->buf[sl->len++]= ( char )( (data>>32)&0xff );
113
114			sl->buf[sl->len++]= ( char )( (data>>24)&0xff );
115			sl->buf[sl->len++]= ( char )( (data>>16)&0xff );
116			sl->buf[sl->len++]= ( char )( (data>>8)&0xff );
117			sl->buf[sl->len++] =( char )( data & 0xff );
118			}
119
120			/* Basically does the reverse of SockList_AddInt, but on
121			* strings instead. Same for the GetShort, but for 16 bits.
122			*/
123			int GetInt_String(unsigned char *data)
124			{
125			return ((data[0]<<24) + (data[1]<<16) + (data[2]<<8) + data[3]);
126			}
127
128			short GetShort_String(unsigned char *data) {
129			return ((data[0]<<8)+data[1]);
130			}
131
132			/******************************************************************************
133			*
134			* Start of read routines.
135			*
136			******************************************************************************/
137
138			/**
139			* This reads from fd and puts the data in sl. We return true if we think
140			* we have a full packet, 0 if we have a partial packet. The only processing
141			* we do is remove the intial size value. len (As passed) is the size of the
142			* buffer allocated in the socklist. We make the assumption the buffer is
143			* at least 2 bytes long.
144			*/
145
146			int SockList_ReadPacket(int fd, SockList *sl, int len)
147			{
148			int stat,toread;
149
150			/* Sanity check - shouldn't happen */
151			if (sl->len < 0) {
152	root	1.3	abort();
153	elmex	1.1	}
154			/* We already have a partial packet */
155			if (sl->len<2) {
156			#ifdef WIN32 /* **WIN32 SockList_ReadPacket: change read() to recv() /
157
158	root	1.3	stat=recv(fd, sl->buf + sl->len, 2-sl->len,0);
159	elmex	1.1
160			#else
161	root	1.3	do {
162			stat=read(fd, sl->buf + sl->len, 2-sl->len);
163			} while ((stat==-1) && (errno==EINTR));
164			#endif
165			if (stat<0) {
166			/* In non blocking mode, EAGAIN is set when there is no
167			* data available.
168			*/
169	elmex	1.1	#ifdef WIN32 /* **WIN32 SockList_ReadPacket: error handling for win32 /
170	root	1.3	if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
171			if(WSAGetLastError() == WSAECONNRESET)
172			LOG(llevDebug,"Connection closed by client\n");
173			else
174			{
175			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
176			}
177			return -1; /* kick this user! */
178			}
179	elmex	1.1	#else
180	root	1.3	if (errno != EAGAIN && errno !=EWOULDBLOCK) {
181	root	1.4	LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror(errno));
182	root	1.3	}
183			#endif
184			return 0; /Error /
185			}
186			if (stat==0) return -1;
187			sl->len += stat;
188	elmex	1.1	#ifdef CS_LOGSTATS
189	root	1.3	cst_tot.ibytes += stat;
190			cst_lst.ibytes += stat;
191	elmex	1.1	#endif
192	root	1.3	if (stat<2) return 0; /* Still don't have a full packet */
193	elmex	1.1	}
194			/* Figure out how much more data we need to read. Add 2 from the
195			* end of this - size header information is not included.
196			*/
197			toread = 2+(sl->buf[0] << 8) + sl->buf[1] - sl->len;
198			if ((toread + sl->len) >= len) {
199	root	1.3	LOG(llevError,"SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n",
200			toread + sl->len, len);
201			/* Quick hack in case for 'oldsocketmode' input. If we are
202			* closing the socket anyways, then reading this extra 100 bytes
203			* shouldn't hurt.
204			*/
205	elmex	1.1	#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
206	root	1.3	recv(fd, sl->buf+2, 100, 0);
207	elmex	1.1	#else
208	root	1.3	read(fd, sl->buf+2, 100);
209	elmex	1.1	#endif /* end win32 */
210
211	root	1.3	/* return error so the socket is closed */
212			return -1;
213	elmex	1.1	}
214			do {
215			#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
216	root	1.3	stat = recv(fd, sl->buf+ sl->len, toread, 0);
217	elmex	1.1	#else
218	root	1.3	do {
219			stat = read(fd, sl->buf+ sl->len, toread);
220			} while ((stat<0) && (errno==EINTR));
221	elmex	1.1	#endif
222	root	1.3	if (stat<0) {
223	elmex	1.1
224			#ifdef WIN32 /* **win32 SockList_ReadPacket: change error handling for win32 /
225	root	1.3	if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
226			if(WSAGetLastError() == WSAECONNRESET)
227			LOG(llevDebug,"Connection closed by client\n");
228			else
229			{
230			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
231			}
232			return -1; /* kick this user! */
233			}
234	elmex	1.1	#else
235	root	1.3	if (errno != EAGAIN && errno !=EWOULDBLOCK) {
236	root	1.4	LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror(errno));
237	root	1.3	}
238			#endif
239			return 0; /Error /
240			}
241			if (stat==0) return -1;
242			sl->len += stat;
243	elmex	1.1	#ifdef CS_LOGSTATS
244	root	1.3	cst_tot.ibytes += stat;
245			cst_lst.ibytes += stat;
246	elmex	1.1	#endif
247	root	1.3	toread -= stat;
248			if (toread==0) return 1;
249			if (toread < 0) {
250			LOG(llevError,"SockList_ReadPacket: Read more bytes than desired.\n");
251			return 1;
252			}
253	elmex	1.1	} while (toread>0);
254			return 0;
255			}
256
257			/*******************************************************************************
258			*
259			* Start of write related routines.
260			*
261			******************************************************************************/
262
263			/**
264			* Adds data to a socket buffer for whatever reason.
265			*
266			* ns is the socket we are adding the data to, buf is the start of the
267			* data, and len is the number of bytes to add.
268			*/
269
270			static void add_to_buffer(NewSocket ns, char buf, int len)
271			{
272			int avail, end;
273
274			if ((len+ns->outputbuffer.len)>SOCKETBUFSIZE) {
275	root	1.3	LOG(llevDebug,"Socket on fd %d has overrun internal buffer - marking as dead\n",
276			ns->fd);
277			ns->status = Ns_Dead;
278			return;
279	elmex	1.1	}
280
281			/* data + end is where we start putting the new data. The last byte
282			* currently in use is actually data + end -1
283			*/
284
285			end=ns->outputbuffer.start + ns->outputbuffer.len;
286			/* The buffer is already in a wrapped state, so adjust end */
287			if (end>=SOCKETBUFSIZE) end-=SOCKETBUFSIZE;
288			avail=SOCKETBUFSIZE - end;
289
290			/* We can all fit it behind the current data without wrapping */
291			if (avail >=len ) {
292	root	1.3	memcpy(ns->outputbuffer.data + end, buf, len);
293	elmex	1.1	}
294			else {
295	root	1.3	memcpy(ns->outputbuffer.data + end, buf, avail);
296			memcpy(ns->outputbuffer.data, buf+avail, len-avail);
297	elmex	1.1	}
298			ns->outputbuffer.len += len;
299			#if 0
300			LOG(llevDebug,"Added %d to output buffer, total length now %d, start=%d\n", len,
301	root	1.3	ns->outputbuffer.len, ns->outputbuffer.start);
302	elmex	1.1	#endif
303			}
304
305			/**
306			* Writes data to socket.
307			*
308			* When the socket is clear to write, and we have backlogged data, this
309			* is called to write it out.
310			*/
311			void write_socket_buffer(NewSocket *ns)
312			{
313			int amt, max;
314
315			if (ns->outputbuffer.len==0) {
316	root	1.3	LOG(llevDebug,"write_socket_buffer called when there is no data, fd=%d\n",
317			ns->fd);
318			return;
319	elmex	1.1	}
320
321			do {
322	root	1.3	max = SOCKETBUFSIZE - ns->outputbuffer.start;
323			if (ns->outputbuffer.len<max) max = ns->outputbuffer.len;
324	elmex	1.1
325			#ifdef WIN32 /* **win32 write_socket_buffer: change write() to send() /
326	root	1.3	amt=send(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max,0);
327	elmex	1.1	#else
328	root	1.3	do {
329			amt=write(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
330			} while ((amt<0) && (errno==EINTR));
331	elmex	1.1	#endif
332
333	root	1.3	if (amt < 0) { /* We got an error */
334	elmex	1.1
335			#ifdef WIN32 /* **win32 write_socket_buffer: change error handling /
336	root	1.3	if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
337			LOG(llevError,"New socket write failed (wsb) (%d).\n", WSAGetLastError());
338	elmex	1.1	#else
339	root	1.3	if (errno !=EWOULDBLOCK) {
340			LOG(llevError,"New socket write failed (wsb) (%d: %s).\n",
341	root	1.4	errno, strerror(errno));
342	root	1.3	#endif
343			ns->status=Ns_Dead;
344			return;
345			}
346			else { /* EWOULDBLOCK */
347			/* can't write it, so store it away. */
348			ns->can_write=0;
349			return;
350			}
351			}
352			ns->outputbuffer.start += amt;
353			/* wrap back to start of buffer */
354			if (ns->outputbuffer.start==SOCKETBUFSIZE) ns->outputbuffer.start=0;
355			ns->outputbuffer.len -= amt;
356	elmex	1.1	#ifdef CS_LOGSTATS
357	root	1.3	cst_tot.obytes += amt;
358			cst_lst.obytes += amt;
359	elmex	1.1	#endif
360			} while (ns->outputbuffer.len>0);
361			}
362
363			/**
364			* This writes data to the socket. - It is very low level -
365			* all we try and do is write out the data to the socket
366			* provided (ns). buf is the data to write, len is the number
367			* of bytes to write. IT doesn't return anything - rather, it
368			* updates the ns structure if we get an error.
369			*/
370			void Write_To_Socket(NewSocket ns, char buf, int len)
371			{
372			int amt=0;
373			char *pos=buf;
374
375			if (ns->status == Ns_Dead \|\| !buf) {
376	root	1.3	LOG(llevDebug,"Write_To_Socket called with dead socket\n");
377			return;
378	elmex	1.1	}
379
380			#ifndef __GNU__ /* This caused problems on Hurd */
381			if (!ns->can_write) {
382	root	1.3	add_to_buffer(ns, buf, len);
383			return;
384	elmex	1.1	}
385			#endif
386			/* If we manage to write more than we wanted, take it as a bonus */
387			while (len>0) {
388
389			#ifdef WIN32 /* **win32 Write_To_Socket: change write() to send() /
390	root	1.3	amt=send(ns->fd, pos, len,0);
391	elmex	1.1	#else
392	root	1.3	do {
393			amt=write(ns->fd, pos, len);
394			} while ((amt<0) && (errno==EINTR));
395	elmex	1.1	#endif
396
397	root	1.3	if (amt < 0) { /* We got an error */
398	elmex	1.1	#ifdef WIN32 /* **win32 Write_To_Socket: change error handling /
399	root	1.3	if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
400			LOG(llevError,"New socket write failed WTS (%d).\n",WSAGetLastError());
401	elmex	1.1	#else
402	root	1.3	if (errno !=EWOULDBLOCK) {
403			LOG(llevError,"New socket write failed WTS (%d: %s).\n", /* ---WIN32 */
404	root	1.4	errno, strerror(errno));
405	root	1.3	#endif
406			ns->status=Ns_Dead;
407			return;
408			}
409			else { /* EWOULDBLOCK */
410			/* can't write it, so store it away. */
411			add_to_buffer(ns, pos, len);
412			ns->can_write=0;
413			return;
414			}
415			}
416			/* amt gets set to 0 above in blocking code, so we do this as
417			* an else if to make sure we don't reprocess it.
418			*/
419			else if (amt==0) {
420			LOG(llevError,"Write_To_Socket: No data written out.\n");
421			}
422			len -= amt;
423			pos += amt;
424	elmex	1.1	#ifdef CS_LOGSTATS
425	root	1.3	cst_tot.obytes += amt;
426			cst_lst.obytes += amt;
427	elmex	1.1	#endif
428			}
429			}
430
431
432			/**
433			* Takes a string of data, and writes it out to the socket. A very handy
434			* shortcut function.
435			*/
436			void cs_write_string(NewSocket ns, const char buf, int len)
437			{
438			SockList sl;
439
440			sl.len = len;
441			sl.buf = (unsigned char*)buf;
442			Send_With_Handling(ns, &sl);
443			}
444
445
446			/**
447			* Calls Write_To_Socket to send data to the client.
448			*
449			* The only difference in this function is that we take a SockList
450			*, and we prepend the length information.
451			*/
452			void Send_With_Handling(NewSocket ns,SockList msg)
453			{
454			unsigned char sbuf[4];
455
456			if (ns->status == Ns_Dead \|\| !msg)
457	root	1.3	return;
458	elmex	1.1
459			if (msg->len >= MAXSOCKBUF) {
460	root	1.3	LOG(llevError,"Trying to send a buffer beyond properly size, len =%d\n",
461			msg->len);
462			/* Almost certainly we've overflowed a buffer, so quite now to make
463			* it easier to debug.
464			*/
465			abort();
466	elmex	1.1	}
467			sbuf[0] = ((uint32)(msg->len) >> 8) & 0xFF;
468			sbuf[1] = ((uint32)(msg->len)) & 0xFF;
469			if (ns->status != Ns_Old)
470	root	1.3	Write_To_Socket(ns, (char *) sbuf, 2);
471	elmex	1.1	Write_To_Socket(ns, (char*)msg->buf, msg->len);
472			}
473
474			/**
475			* Takes a string of data, and writes it out to the socket. A very handy
476			* shortcut function.
477			*/
478			void Write_String_To_Socket(NewSocket ns, char buf, int len)
479			{
480			SockList sl;
481
482			sl.len = len;
483			sl.buf = (unsigned char*) buf;
484			Send_With_Handling(ns, &sl);
485			}
486
487
488			/******************************************************************************
489			*
490			* statistics logging functions.
491			*
492			******************************************************************************/
493
494			#ifdef CS_LOGSTATS
495			/* 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			void write_cs_stats(void)
504			{
505			time_t now=time(NULL);
506
507			/* If no connections recently, don't both to log anything */
508			if (cst_lst.ibytes==0 && cst_lst.obytes==0) return;
509
510			/* CSSTAT is put in so scripts can easily find the line */
511			LOG(llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
512	root	1.3	ctime(&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
513			now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes,
514			cst_lst.max_conn, now - cst_lst.time_start);
515	elmex	1.1	cst_lst.ibytes=0;
516			cst_lst.obytes=0;
517			cst_lst.max_conn=socket_info.nconns;
518			cst_lst.time_start=now;
519			}
520			#endif