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|
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/* |
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* static char *rcsid_sockets_c = |
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* "$Id: lowlevel.C,v 1.3 2006-08-29 08:01:38 root Exp $"; |
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*/ |
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|
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/* |
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CrossFire, A Multiplayer game for X-windows |
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|
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Copyright (C) 1992 Frank Tore Johansen |
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|
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This program is free software; you can redistribute it and/or modify |
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it under the terms of the GNU General Public License as published by |
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the Free Software Foundation; either version 2 of the License, or |
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(at your option) any later version. |
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|
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This program is distributed in the hope that it will be useful, |
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but WITHOUT ANY WARRANTY; without even the implied warranty of |
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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GNU General Public License for more details. |
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|
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You should have received a copy of the GNU General Public License |
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along with this program; if not, write to the Free Software |
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
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|
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The author can be reached via e-mail to mark@pyramid.com |
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*/ |
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|
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/** |
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* \file |
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* Low-level socket-related functions. |
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* |
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* \date 2003-12-02 |
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* |
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* Contains some base functions that both the client and server |
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* can use. As such, depending what we are being compiled for will |
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* determine what we can include. the client is designed have |
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* CFCLIENT defined as part of its compile flags. |
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*/ |
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|
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using namespace std; |
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|
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#include <global.h> |
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#include <newclient.h> |
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#include <sproto.h> |
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|
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#ifdef __linux__ |
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# include <sys/types.h> |
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# include <sys/socket.h> |
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# include <netinet/in.h> |
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# define TCP_HZ 1000 // sorry... |
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# include <netinet/tcp.h> |
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#endif |
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|
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// use a really low timeout, as it doesn't cost any bandwidth, and you can |
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// easily die in 20 seconds... |
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#define SOCKET_TIMEOUT1 10 |
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#define SOCKET_TIMEOUT2 20 |
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|
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void Socket_Flush (NewSocket *ns) |
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{ |
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#ifdef __linux__ |
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// check time of last ack, and, if too old, kill connection |
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struct tcp_info tcpi; |
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socklen_t len = sizeof (tcpi); |
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|
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if (!getsockopt (ns->fd, IPPROTO_TCP, TCP_INFO, &tcpi, &len) && len == sizeof (tcpi)) |
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{ |
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unsigned int diff = tcpi.tcpi_last_ack_recv - tcpi.tcpi_last_data_sent; |
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|
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if (tcpi.tcpi_unacked |
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&& SOCKET_TIMEOUT1 * TCP_HZ < diff && diff < 0x80000000UL // ack delayed for 20s |
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&& SOCKET_TIMEOUT2 * TCP_HZ < tcpi.tcpi_last_data_sent) // no data sent for 10s |
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{ |
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LOG (llevDebug, "Connection on fd %d closed due to ack timeout (%u/%u/%u)\n", ns->fd, |
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(unsigned)tcpi.tcpi_last_ack_recv, (unsigned)tcpi.tcpi_last_data_sent, (unsigned)tcpi.tcpi_unacked); |
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ns->status = Ns_Dead; |
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} |
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} |
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|
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int val; |
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val = 0; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val)); |
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val = 1; setsockopt (ns->fd, IPPROTO_TCP, TCP_CORK, &val, sizeof (val)); |
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#endif |
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} |
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|
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/*********************************************************************** |
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* |
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* SockList functions/utilities |
90 |
* |
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**********************************************************************/ |
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|
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void SockList_Init(SockList *sl) |
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{ |
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sl->len=0; |
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sl->buf=NULL; |
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} |
98 |
|
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void SockList_AddInt(SockList *sl, uint32 data) |
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{ |
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sl->buf[sl->len++]= (data>>24)&0xff; |
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sl->buf[sl->len++]= (data>>16)&0xff; |
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sl->buf[sl->len++]= (data>>8)&0xff; |
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sl->buf[sl->len++] = data & 0xff; |
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} |
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|
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void SockList_AddInt64(SockList *sl, uint64 data) |
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{ |
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sl->buf[sl->len++]= ( char )( (data>>56)&0xff ); |
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sl->buf[sl->len++]= ( char )( (data>>48)&0xff ); |
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sl->buf[sl->len++]= ( char )( (data>>40)&0xff ); |
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sl->buf[sl->len++]= ( char )( (data>>32)&0xff ); |
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|
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sl->buf[sl->len++]= ( char )( (data>>24)&0xff ); |
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sl->buf[sl->len++]= ( char )( (data>>16)&0xff ); |
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sl->buf[sl->len++]= ( char )( (data>>8)&0xff ); |
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sl->buf[sl->len++] =( char )( data & 0xff ); |
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} |
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|
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/* Basically does the reverse of SockList_AddInt, but on |
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* strings instead. Same for the GetShort, but for 16 bits. |
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*/ |
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int GetInt_String(unsigned char *data) |
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{ |
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return ((data[0]<<24) + (data[1]<<16) + (data[2]<<8) + data[3]); |
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} |
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|
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short GetShort_String(unsigned char *data) { |
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return ((data[0]<<8)+data[1]); |
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} |
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|
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/****************************************************************************** |
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* |
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* Start of read routines. |
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* |
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******************************************************************************/ |
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|
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/** |
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* This reads from fd and puts the data in sl. We return true if we think |
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* we have a full packet, 0 if we have a partial packet. The only processing |
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* we do is remove the intial size value. len (As passed) is the size of the |
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* buffer allocated in the socklist. We make the assumption the buffer is |
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* at least 2 bytes long. |
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*/ |
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|
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int SockList_ReadPacket(int fd, SockList *sl, int len) |
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{ |
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int stat,toread; |
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|
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/* Sanity check - shouldn't happen */ |
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if (sl->len < 0) { |
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abort(); |
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} |
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/* We already have a partial packet */ |
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if (sl->len<2) { |
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#ifdef WIN32 /* ***WIN32 SockList_ReadPacket: change read() to recv() */ |
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|
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stat=recv(fd, sl->buf + sl->len, 2-sl->len,0); |
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|
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#else |
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do { |
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stat=read(fd, sl->buf + sl->len, 2-sl->len); |
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} while ((stat==-1) && (errno==EINTR)); |
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#endif |
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if (stat<0) { |
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/* In non blocking mode, EAGAIN is set when there is no |
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* data available. |
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*/ |
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#ifdef WIN32 /* ***WIN32 SockList_ReadPacket: error handling for win32 */ |
170 |
if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) { |
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if(WSAGetLastError() == WSAECONNRESET) |
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LOG(llevDebug,"Connection closed by client\n"); |
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else |
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{ |
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LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError()); |
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} |
177 |
return -1; /* kick this user! */ |
178 |
} |
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#else |
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if (errno != EAGAIN && errno !=EWOULDBLOCK) { |
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LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror(errno)); |
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} |
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#endif |
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return 0; /*Error */ |
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} |
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if (stat==0) return -1; |
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sl->len += stat; |
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#ifdef CS_LOGSTATS |
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cst_tot.ibytes += stat; |
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cst_lst.ibytes += stat; |
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#endif |
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if (stat<2) return 0; /* Still don't have a full packet */ |
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} |
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/* Figure out how much more data we need to read. Add 2 from the |
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* end of this - size header information is not included. |
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*/ |
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toread = 2+(sl->buf[0] << 8) + sl->buf[1] - sl->len; |
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if ((toread + sl->len) >= len) { |
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LOG(llevError,"SockList_ReadPacket: Want to read more bytes than will fit in buffer (%d>=%d).\n", |
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toread + sl->len, len); |
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/* Quick hack in case for 'oldsocketmode' input. If we are |
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* closing the socket anyways, then reading this extra 100 bytes |
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* shouldn't hurt. |
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*/ |
205 |
#ifdef WIN32 /* ***win32 SockList_ReadPacket: change read() to recv() */ |
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recv(fd, sl->buf+2, 100, 0); |
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#else |
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read(fd, sl->buf+2, 100); |
209 |
#endif /* end win32 */ |
210 |
|
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/* return error so the socket is closed */ |
212 |
return -1; |
213 |
} |
214 |
do { |
215 |
#ifdef WIN32 /* ***win32 SockList_ReadPacket: change read() to recv() */ |
216 |
stat = recv(fd, sl->buf+ sl->len, toread, 0); |
217 |
#else |
218 |
do { |
219 |
stat = read(fd, sl->buf+ sl->len, toread); |
220 |
} while ((stat<0) && (errno==EINTR)); |
221 |
#endif |
222 |
if (stat<0) { |
223 |
|
224 |
#ifdef WIN32 /* ***win32 SockList_ReadPacket: change error handling for win32 */ |
225 |
if ((stat==-1) && WSAGetLastError() !=WSAEWOULDBLOCK) { |
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if(WSAGetLastError() == WSAECONNRESET) |
227 |
LOG(llevDebug,"Connection closed by client\n"); |
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else |
229 |
{ |
230 |
LOG(llevDebug,"ReadPacket got error %d, returning 0\n",WSAGetLastError()); |
231 |
} |
232 |
return -1; /* kick this user! */ |
233 |
} |
234 |
#else |
235 |
if (errno != EAGAIN && errno !=EWOULDBLOCK) { |
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LOG(llevDebug, "ReadPacket got error %s, returning 0\n", strerror(errno)); |
237 |
} |
238 |
#endif |
239 |
return 0; /*Error */ |
240 |
} |
241 |
if (stat==0) return -1; |
242 |
sl->len += stat; |
243 |
#ifdef CS_LOGSTATS |
244 |
cst_tot.ibytes += stat; |
245 |
cst_lst.ibytes += stat; |
246 |
#endif |
247 |
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 |
} 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 |
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 |
} |
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 |
memcpy(ns->outputbuffer.data + end, buf, len); |
293 |
} |
294 |
else { |
295 |
memcpy(ns->outputbuffer.data + end, buf, avail); |
296 |
memcpy(ns->outputbuffer.data, buf+avail, len-avail); |
297 |
} |
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 |
ns->outputbuffer.len, ns->outputbuffer.start); |
302 |
#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 |
LOG(llevDebug,"write_socket_buffer called when there is no data, fd=%d\n", |
317 |
ns->fd); |
318 |
return; |
319 |
} |
320 |
|
321 |
do { |
322 |
max = SOCKETBUFSIZE - ns->outputbuffer.start; |
323 |
if (ns->outputbuffer.len<max) max = ns->outputbuffer.len; |
324 |
|
325 |
#ifdef WIN32 /* ***win32 write_socket_buffer: change write() to send() */ |
326 |
amt=send(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max,0); |
327 |
#else |
328 |
do { |
329 |
amt=write(ns->fd, ns->outputbuffer.data + ns->outputbuffer.start, max); |
330 |
} while ((amt<0) && (errno==EINTR)); |
331 |
#endif |
332 |
|
333 |
if (amt < 0) { /* We got an error */ |
334 |
|
335 |
#ifdef WIN32 /* ***win32 write_socket_buffer: change error handling */ |
336 |
if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) { |
337 |
LOG(llevError,"New socket write failed (wsb) (%d).\n", WSAGetLastError()); |
338 |
#else |
339 |
if (errno !=EWOULDBLOCK) { |
340 |
LOG(llevError,"New socket write failed (wsb) (%d: %s).\n", |
341 |
errno, strerror(errno)); |
342 |
#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 |
#ifdef CS_LOGSTATS |
357 |
cst_tot.obytes += amt; |
358 |
cst_lst.obytes += amt; |
359 |
#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 |
LOG(llevDebug,"Write_To_Socket called with dead socket\n"); |
377 |
return; |
378 |
} |
379 |
|
380 |
#ifndef __GNU__ /* This caused problems on Hurd */ |
381 |
if (!ns->can_write) { |
382 |
add_to_buffer(ns, buf, len); |
383 |
return; |
384 |
} |
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 |
amt=send(ns->fd, pos, len,0); |
391 |
#else |
392 |
do { |
393 |
amt=write(ns->fd, pos, len); |
394 |
} while ((amt<0) && (errno==EINTR)); |
395 |
#endif |
396 |
|
397 |
if (amt < 0) { /* We got an error */ |
398 |
#ifdef WIN32 /* ***win32 Write_To_Socket: change error handling */ |
399 |
if (amt == -1 && WSAGetLastError() !=WSAEWOULDBLOCK) { |
400 |
LOG(llevError,"New socket write failed WTS (%d).\n",WSAGetLastError()); |
401 |
#else |
402 |
if (errno !=EWOULDBLOCK) { |
403 |
LOG(llevError,"New socket write failed WTS (%d: %s).\n", /* ---WIN32 */ |
404 |
errno, strerror(errno)); |
405 |
#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 |
#ifdef CS_LOGSTATS |
425 |
cst_tot.obytes += amt; |
426 |
cst_lst.obytes += amt; |
427 |
#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 |
return; |
458 |
|
459 |
if (msg->len >= MAXSOCKBUF) { |
460 |
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 |
} |
467 |
sbuf[0] = ((uint32)(msg->len) >> 8) & 0xFF; |
468 |
sbuf[1] = ((uint32)(msg->len)) & 0xFF; |
469 |
if (ns->status != Ns_Old) |
470 |
Write_To_Socket(ns, (char *) sbuf, 2); |
471 |
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 |
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 |
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 |