/* Unix SMB/Netbios implementation. Version 1.9. connection claim routines Copyright (C) Andrew Tridgell 1998 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. */ #include "includes.h" extern fstring remote_machine; extern int DEBUGLEVEL; /**************************************************************************** simple routines to do connection counting ****************************************************************************/ BOOL yield_connection(connection_struct *conn,char *name,int max_connections) { struct connect_record crec; pstring fname; int fd; int mypid = getpid(); int i; DEBUG(3,("Yielding connection to %s\n",name)); if (max_connections <= 0) return(True); bzero(&crec,sizeof(crec)); pstrcpy(fname,lp_lockdir()); trim_string(fname,"","/"); pstrcat(fname,"/"); pstrcat(fname,name); pstrcat(fname,".LCK"); fd = open(fname,O_RDWR); if (fd == -1) { DEBUG(2,("Couldn't open lock file %s (%s)\n",fname,strerror(errno))); return(False); } if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_WRLCK)==False) { DEBUG(0,("ERROR: can't get lock on %s\n", fname)); return False; } /* find the right spot */ for (i=0;i<max_connections;i++) { if (read(fd, &crec,sizeof(crec)) != sizeof(crec)) { DEBUG(2,("Entry not found in lock file %s\n",fname)); if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_UNLCK)==False) { DEBUG(0,("ERROR: can't release lock on %s\n", fname)); } close(fd); return(False); } if (crec.pid == mypid && crec.cnum == conn->cnum) break; } if (crec.pid != mypid || crec.cnum != conn->cnum) { if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_UNLCK)==False) { DEBUG(0,("ERROR: can't release lock on %s\n", fname)); } close(fd); DEBUG(2,("Entry not found in lock file %s\n",fname)); return(False); } bzero((void *)&crec,sizeof(crec)); /* remove our mark */ if (sys_lseek(fd,i*sizeof(crec),SEEK_SET) != i*sizeof(crec) || write(fd, &crec,sizeof(crec)) != sizeof(crec)) { DEBUG(2,("Couldn't update lock file %s (%s)\n",fname,strerror(errno))); if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_UNLCK)==False) { DEBUG(0,("ERROR: can't release lock on %s\n", fname)); } close(fd); return(False); } if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_UNLCK)==False) { DEBUG(0,("ERROR: can't release lock on %s\n", fname)); } DEBUG(3,("Yield successful\n")); close(fd); return(True); } /**************************************************************************** simple routines to do connection counting ****************************************************************************/ BOOL claim_connection(connection_struct *conn,char *name,int max_connections,BOOL Clear) { extern int Client; struct connect_record crec; pstring fname; int fd=-1; int i,foundi= -1; int total_recs; if (max_connections <= 0) return(True); DEBUG(5,("trying claim %s %s %d\n",lp_lockdir(),name,max_connections)); pstrcpy(fname,lp_lockdir()); trim_string(fname,"","/"); if (!directory_exist(fname,NULL)) mkdir(fname,0755); pstrcat(fname,"/"); pstrcat(fname,name); pstrcat(fname,".LCK"); if (!file_exist(fname,NULL)) { fd = open(fname,O_RDWR|O_CREAT|O_EXCL, 0644); } if (fd == -1) { fd = open(fname,O_RDWR); } if (fd == -1) { DEBUG(1,("couldn't open lock file %s\n",fname)); return(False); } if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_WRLCK)==False) { DEBUG(0,("ERROR: can't get lock on %s\n", fname)); return False; } total_recs = file_size(fname) / sizeof(crec); /* find a free spot */ for (i=0;i<max_connections;i++) { if (i>=total_recs || sys_lseek(fd,i*sizeof(crec),SEEK_SET) != i*sizeof(crec) || read(fd,&crec,sizeof(crec)) != sizeof(crec)) { if (foundi < 0) foundi = i; break; } if (Clear && crec.pid && !process_exists(crec.pid)) { sys_lseek(fd,i*sizeof(crec),SEEK_SET); bzero((void *)&crec,sizeof(crec)); write(fd, &crec,sizeof(crec)); if (foundi < 0) foundi = i; continue; } if (foundi < 0 && (!crec.pid || !process_exists(crec.pid))) { foundi=i; if (!Clear) break; } } if (foundi < 0) { DEBUG(3,("no free locks in %s\n",fname)); if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_UNLCK)==False) { DEBUG(0,("ERROR: can't release lock on %s\n", fname)); } close(fd); return(False); } /* fill in the crec */ bzero((void *)&crec,sizeof(crec)); crec.magic = 0x280267; crec.pid = getpid(); if (conn) { crec.cnum = conn->cnum; crec.uid = conn->uid; crec.gid = conn->gid; StrnCpy(crec.name, lp_servicename(SNUM(conn)),sizeof(crec.name)-1); } else { crec.cnum = -1; } crec.start = time(NULL); StrnCpy(crec.machine,remote_machine,sizeof(crec.machine)-1); StrnCpy(crec.addr,client_addr(Client),sizeof(crec.addr)-1); /* make our mark */ if (sys_lseek(fd,foundi*sizeof(crec),SEEK_SET) != foundi*sizeof(crec) || write(fd, &crec,sizeof(crec)) != sizeof(crec)) { if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_UNLCK)==False) { DEBUG(0,("ERROR: can't release lock on %s\n", fname)); } close(fd); return(False); } if (fcntl_lock(fd,SMB_F_SETLKW,0,1,F_UNLCK)==False) { DEBUG(0,("ERROR: can't release lock on %s\n", fname)); } close(fd); return(True); }