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...
#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;
    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:	1.6
Committed:	Sun Aug 13 17:16:06 2006 UTC (20 years, 2 months ago) by elmex
Content type:	text/plain
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.5:	+0 -0 lines
State:	*FILE REMOVED*
Log Message:	Made server compile with C++. Removed cfanim plugin and crossedit. C++ here we come.
#	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	root	1.5	// easily die in 20 seconds...
55			#define SOCKET_TIMEOUT1 10
56			#define SOCKET_TIMEOUT2 20
57	root	1.3
58	root	1.2	void Socket_Flush (NewSocket *ns)
59			{
60			#ifdef __linux__
61	root	1.3	// check time of last ack, and, if too old, kill connection
62			struct tcp_info tcpi;
63			socklen_t len = sizeof (tcpi);
64	root	1.4
65	root	1.3	if (!getsockopt (ns->fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi))
66			{
67			unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent;
68
69	root	1.5	if (tcpi.tcpi_unacked
70			&& SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL // ack delayed for 20s
71			&& SOCKET_TIMEOUT2 * TCP_HZ < tcpi.tcpi_last_data_sent) // no data sent for 10s
72	root	1.3	{
73	root	1.4	LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd,
74			(unsigned)tcpi.tcpi_last_ack_recv, (unsigned)tcpi.tcpi_last_data_sent, (unsigned)tcpi.tcpi_unacked);
75	root	1.3	ns->status = Ns_Dead;
76			}
77			}
78	root	1.4
79			int val;
80			val = 0; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
81			val = 1; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val));
82	root	1.2	#endif
83			}
84
85	root	1.1	/***********************************************************************
86			*
87			* SockList functions/utilities
88			*
89			**********************************************************************/
90
91			void SockList_Init(SockList *sl)
92			{
93			sl->len=0;
94			sl->buf=NULL;
95			}
96
97			void SockList_AddChar(SockList *sl, char c)
98			{
99			sl->buf[sl->len]=c;
100			sl->len++;
101			}
102
103			void SockList_AddShort(SockList *sl, uint16 data)
104			{
105			sl->buf[sl->len++]= (data>>8)&0xff;
106			sl->buf[sl->len++] = data & 0xff;
107			}
108
109
110			void SockList_AddInt(SockList *sl, uint32 data)
111			{
112			sl->buf[sl->len++]= (data>>24)&0xff;
113			sl->buf[sl->len++]= (data>>16)&0xff;
114			sl->buf[sl->len++]= (data>>8)&0xff;
115			sl->buf[sl->len++] = data & 0xff;
116			}
117
118			void SockList_AddInt64(SockList *sl, uint64 data)
119			{
120			sl->buf[sl->len++]= ( char )( (data>>56)&0xff );
121			sl->buf[sl->len++]= ( char )( (data>>48)&0xff );
122			sl->buf[sl->len++]= ( char )( (data>>40)&0xff );
123			sl->buf[sl->len++]= ( char )( (data>>32)&0xff );
124
125			sl->buf[sl->len++]= ( char )( (data>>24)&0xff );
126			sl->buf[sl->len++]= ( char )( (data>>16)&0xff );
127			sl->buf[sl->len++]= ( char )( (data>>8)&0xff );
128			sl->buf[sl->len++] =( char )( data & 0xff );
129			}
130
131			/* Basically does the reverse of SockList_AddInt, but on
132			* strings instead. Same for the GetShort, but for 16 bits.
133			*/
134			int GetInt_String(unsigned char *data)
135			{
136			return ((data[0]<<24) + (data[1]<<16) + (data[2]<<8) + data[3]);
137			}
138
139			short GetShort_String(unsigned char *data) {
140			return ((data[0]<<8)+data[1]);
141			}
142
143			/******************************************************************************
144			*
145			* Start of read routines.
146			*
147			******************************************************************************/
148
149			/**
150			* This reads from fd and puts the data in sl. We return true if we think
151			* we have a full packet, 0 if we have a partial packet. The only processing
152			* we do is remove the intial size value. len (As passed) is the size of the
153			* buffer allocated in the socklist. We make the assumption the buffer is
154			* at least 2 bytes long.
155			*/
156
157			int SockList_ReadPacket(int fd, SockList *sl, int len)
158			{
159			int stat,toread;
160			extern int errno;
161
162			/* Sanity check - shouldn't happen */
163			if (sl->len < 0) {
164			abort();
165			}
166			/* We already have a partial packet */
167			if (sl->len<2) {
168			#ifdef WIN32 /* **WIN32 SockList_ReadPacket: change read() to recv() /
169
170			stat=recv(fd, sl->buf + sl->len, 2-sl->len,0);
171
172			#else
173			do {
174			stat=read(fd, sl->buf + sl->len, 2-sl->len);
175			} while ((stat==-1) && (errno==EINTR));
176			#endif
177			if (stat<0) {
178			/* In non blocking mode, EAGAIN is set when there is no
179			* data available.
180			*/
181			#ifdef WIN32 /* **WIN32 SockList_ReadPacket: error handling for win32 /
182			if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
183			if(WSAGetLastError() == WSAECONNRESET)
184			LOG(llevDebug,"Connection closed by client\n");
185			else
186			{
187			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
188			}
189			return -1; /* kick this user! */
190			}
191			#else
192			if (errno != EAGAIN && errno !=EWOULDBLOCK) {
193			LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
194			}
195			#endif
196			return 0; /Error /
197			}
198			if (stat==0) return -1;
199			sl->len += stat;
200			#ifdef CS_LOGSTATS
201			cst_tot.ibytes += stat;
202			cst_lst.ibytes += stat;
203			#endif
204			if (stat<2) return 0; /* Still don't have a full packet */
205			}
206			/* Figure out how much more data we need to read. Add 2 from the
207			* end of this - size header information is not included.
208			*/
209			toread = 2+(sl->buf[0] << 8) + sl->buf[1] - sl->len;
210			if ((toread + sl->len) >= len) {
211			LOG(llevError,"SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n",
212			toread + sl->len, len);
213			/* Quick hack in case for 'oldsocketmode' input. If we are
214			* closing the socket anyways, then reading this extra 100 bytes
215			* shouldn't hurt.
216			*/
217			#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
218			recv(fd, sl->buf+2, 100, 0);
219			#else
220			read(fd, sl->buf+2, 100);
221			#endif /* end win32 */
222
223			/* return error so the socket is closed */
224			return -1;
225			}
226			do {
227			#ifdef WIN32 /* **win32 SockList_ReadPacket: change read() to recv() /
228			stat = recv(fd, sl->buf+ sl->len, toread, 0);
229			#else
230			do {
231			stat = read(fd, sl->buf+ sl->len, toread);
232			} while ((stat<0) && (errno==EINTR));
233			#endif
234			if (stat<0) {
235
236			#ifdef WIN32 /* **win32 SockList_ReadPacket: change error handling for win32 /
237			if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) {
238			if(WSAGetLastError() == WSAECONNRESET)
239			LOG(llevDebug,"Connection closed by client\n");
240			else
241			{
242			LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError());
243			}
244			return -1; /* kick this user! */
245			}
246			#else
247			if (errno != EAGAIN && errno !=EWOULDBLOCK) {
248			LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror_local(errno));
249			}
250			#endif
251			return 0; /Error /
252			}
253			if (stat==0) return -1;
254			sl->len += stat;
255			#ifdef CS_LOGSTATS
256			cst_tot.ibytes += stat;
257			cst_lst.ibytes += stat;
258			#endif
259			toread -= stat;
260			if (toread==0) return 1;
261			if (toread < 0) {
262			LOG(llevError,"SockList_ReadPacket: Read more bytes than desired.\n");
263			return 1;
264			}
265			} while (toread>0);
266			return 0;
267			}
268
269			/*******************************************************************************
270			*
271			* Start of write related routines.
272			*
273			******************************************************************************/
274
275			/**
276			* Adds data to a socket buffer for whatever reason.
277			*
278			* ns is the socket we are adding the data to, buf is the start of the
279			* data, and len is the number of bytes to add.
280			*/
281
282			static void add_to_buffer(NewSocket ns, unsigned char buf, int len)
283			{
284			int avail, end;
285
286			if ((len+ns->outputbuffer.len)>SOCKETBUFSIZE) {
287			LOG(llevDebug,"Socket on fd %d has overrun internal buffer - marking as dead\n",
288			ns->fd);
289			ns->status = Ns_Dead;
290			return;
291			}
292
293			/* data + end is where we start putting the new data. The last byte
294			* currently in use is actually data + end -1
295			*/
296
297			end=ns->outputbuffer.start + ns->outputbuffer.len;
298			/* The buffer is already in a wrapped state, so adjust end */
299			if (end>=SOCKETBUFSIZE) end-=SOCKETBUFSIZE;
300			avail=SOCKETBUFSIZE - end;
301
302			/* We can all fit it behind the current data without wrapping */
303			if (avail >=len ) {
304			memcpy(ns->outputbuffer.data + end, buf, len);
305			}
306			else {
307			memcpy(ns->outputbuffer.data + end, buf, avail);
308			memcpy(ns->outputbuffer.data, buf+avail, len-avail);
309			}
310			ns->outputbuffer.len += len;
311			#if 0
312			LOG(llevDebug,"Added %d to output buffer, total length now %d, start=%d\n", len,
313			ns->outputbuffer.len, ns->outputbuffer.start);
314			#endif
315			}
316
317			/**
318			* Writes data to socket.
319			*
320			* When the socket is clear to write, and we have backlogged data, this
321			* is called to write it out.
322			*/
323			void write_socket_buffer(NewSocket *ns)
324			{
325			int amt, max;
326
327			if (ns->outputbuffer.len==0) {
328			LOG(llevDebug,"write_socket_buffer called when there is no data, fd=%d\n",
329			ns->fd);
330			return;
331			}
332
333			do {
334			max = SOCKETBUFSIZE - ns->outputbuffer.start;
335			if (ns->outputbuffer.len<max) max = ns->outputbuffer.len;
336
337			#ifdef WIN32 /* **win32 write_socket_buffer: change write() to send() /
338			amt=send(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max,0);
339			#else
340			do {
341			amt=write(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max);
342			} while ((amt<0) && (errno==EINTR));
343			#endif
344
345			if (amt < 0) { /* We got an error */
346
347			#ifdef WIN32 /* **win32 write_socket_buffer: change error handling /
348			if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
349			LOG(llevError,"New socket write failed (wsb) (%d).\n", WSAGetLastError());
350			#else
351			if (errno !=EWOULDBLOCK) {
352			LOG(llevError,"New socket write failed (wsb) (%d: %s).\n",
353			errno, strerror_local(errno));
354			#endif
355			ns->status=Ns_Dead;
356			return;
357			}
358			else { /* EWOULDBLOCK */
359			/* can't write it, so store it away. */
360			ns->can_write=0;
361			return;
362			}
363			}
364			ns->outputbuffer.start += amt;
365			/* wrap back to start of buffer */
366			if (ns->outputbuffer.start==SOCKETBUFSIZE) ns->outputbuffer.start=0;
367			ns->outputbuffer.len -= amt;
368			#ifdef CS_LOGSTATS
369			cst_tot.obytes += amt;
370			cst_lst.obytes += amt;
371			#endif
372			} while (ns->outputbuffer.len>0);
373			}
374
375			/**
376			* This writes data to the socket. - It is very low level -
377			* all we try and do is write out the data to the socket
378			* provided (ns). buf is the data to write, len is the number
379			* of bytes to write. IT doesn't return anything - rather, it
380			* updates the ns structure if we get an error.
381			*/
382			void Write_To_Socket(NewSocket ns, unsigned char buf, int len)
383			{
384			int amt=0;
385			unsigned char *pos=buf;
386
387			if (ns->status == Ns_Dead \|\| !buf) {
388			LOG(llevDebug,"Write_To_Socket called with dead socket\n");
389			return;
390			}
391
392			#ifndef __GNU__ /* This caused problems on Hurd */
393			if (!ns->can_write) {
394			add_to_buffer(ns, buf, len);
395			return;
396			}
397			#endif
398			/* If we manage to write more than we wanted, take it as a bonus */
399			while (len>0) {
400
401			#ifdef WIN32 /* **win32 Write_To_Socket: change write() to send() /
402			amt=send(ns->fd, pos, len,0);
403			#else
404			do {
405			amt=write(ns->fd, pos, len);
406			} while ((amt<0) && (errno==EINTR));
407			#endif
408
409			if (amt < 0) { /* We got an error */
410			#ifdef WIN32 /* **win32 Write_To_Socket: change error handling /
411			if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) {
412			LOG(llevError,"New socket write failed WTS (%d).\n",WSAGetLastError());
413			#else
414			if (errno !=EWOULDBLOCK) {
415			LOG(llevError,"New socket write failed WTS (%d: %s).\n", /* ---WIN32 */
416			errno, strerror_local(errno));
417			#endif
418			ns->status=Ns_Dead;
419			return;
420			}
421			else { /* EWOULDBLOCK */
422			/* can't write it, so store it away. */
423			add_to_buffer(ns, pos, len);
424			ns->can_write=0;
425			return;
426			}
427			}
428			/* amt gets set to 0 above in blocking code, so we do this as
429			* an else if to make sure we don't reprocess it.
430			*/
431			else if (amt==0) {
432			LOG(llevError,"Write_To_Socket: No data written out.\n");
433			}
434			len -= amt;
435			pos += amt;
436			#ifdef CS_LOGSTATS
437			cst_tot.obytes += amt;
438			cst_lst.obytes += amt;
439			#endif
440			}
441			}
442
443
444			/**
445			* Takes a string of data, and writes it out to the socket. A very handy
446			* shortcut function.
447			*/
448			void cs_write_string(NewSocket ns, const char buf, int len)
449			{
450			SockList sl;
451
452			sl.len = len;
453			sl.buf = (unsigned char*)buf;
454			Send_With_Handling(ns, &sl);
455			}
456
457
458			/**
459			* Calls Write_To_Socket to send data to the client.
460			*
461			* The only difference in this function is that we take a SockList
462			*, and we prepend the length information.
463			*/
464			void Send_With_Handling(NewSocket ns,SockList msg)
465			{
466			unsigned char sbuf[4];
467
468			if (ns->status == Ns_Dead \|\| !msg)
469			return;
470
471			if (msg->len >= MAXSOCKBUF) {
472			LOG(llevError,"Trying to send a buffer beyond properly size, len =%d\n",
473			msg->len);
474			/* Almost certainly we've overflowed a buffer, so quite now to make
475			* it easier to debug.
476			*/
477			abort();
478			}
479			sbuf[0] = ((uint32)(msg->len) >> 8) & 0xFF;
480			sbuf[1] = ((uint32)(msg->len)) & 0xFF;
481			if (ns->status != Ns_Old)
482			Write_To_Socket(ns, sbuf, 2);
483			Write_To_Socket(ns, msg->buf, msg->len);
484			}
485
486			/**
487			* Takes a string of data, and writes it out to the socket. A very handy
488			* shortcut function.
489			*/
490			void Write_String_To_Socket(NewSocket ns, char buf, int len)
491			{
492			SockList sl;
493
494			sl.len = len;
495			sl.buf = (uint8*)buf;
496			Send_With_Handling(ns, &sl);
497			}
498
499
500			/******************************************************************************
501			*
502			* statistics logging functions.
503			*
504			******************************************************************************/
505
506			#ifdef CS_LOGSTATS
507			/* cst_tot is for the life of the server, cst_last is for the last series of
508			* stats
509			*/
510			CS_Stats cst_tot, cst_lst;
511
512			/**
513			* Writes out the gathered stats. We clear cst_lst.
514			*/
515			void write_cs_stats(void)
516			{
517			time_t now=time(NULL);
518
519			/* If no connections recently, don't both to log anything */
520			if (cst_lst.ibytes==0 && cst_lst.obytes==0) return;
521
522			/* CSSTAT is put in so scripts can easily find the line */
523			LOG(llevInfo, "CSSTAT: %.16s tot %d %d %d %d inc %d %d %d %d\n",
524			ctime(&now), cst_tot.ibytes, cst_tot.obytes, cst_tot.max_conn,
525			now - cst_tot.time_start, cst_lst.ibytes, cst_lst.obytes,
526			cst_lst.max_conn, now - cst_lst.time_start);
527			cst_lst.ibytes=0;
528			cst_lst.obytes=0;
529			cst_lst.max_conn=socket_info.nconns;
530			cst_lst.time_start=now;
531			}
532			#endif