From 0e8fd3398771da2f016d72830179507f3edda51b Mon Sep 17 00:00:00 2001 From: Samba Release Account Date: Sat, 4 May 1996 07:50:46 +0000 Subject: Initial version imported to CVS (This used to be commit 291551d80711daab7b7581720bcd9a08d6096517) --- source3/locking/locking.c | 330 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 330 insertions(+) create mode 100644 source3/locking/locking.c (limited to 'source3/locking') diff --git a/source3/locking/locking.c b/source3/locking/locking.c new file mode 100644 index 0000000000..6ff3ab5d12 --- /dev/null +++ b/source3/locking/locking.c @@ -0,0 +1,330 @@ +/* + Unix SMB/Netbios implementation. + Version 1.9. + Locking functions + Copyright (C) Andrew Tridgell 1992-1995 + + 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" +#include "loadparm.h" +extern int DEBUGLEVEL; +extern connection_struct Connections[]; +extern files_struct Files[]; + +pstring share_del_pending=""; + + +/**************************************************************************** + utility function called to see if a file region is locked +****************************************************************************/ +BOOL is_locked(int fnum,int cnum,uint32 count,uint32 offset) +{ + int snum = SNUM(cnum); + + if (count == 0) + return(False); + + if (!lp_locking(snum) || !lp_strict_locking(snum)) + return(False); + + return(fcntl_lock(Files[fnum].fd,F_GETLK,offset,count, + (Files[fnum].can_write?F_WRLCK:F_RDLCK))); +} + + +/**************************************************************************** + utility function called by locking requests +****************************************************************************/ +BOOL do_lock(int fnum,int cnum,uint32 count,uint32 offset,int *eclass,uint32 *ecode) +{ + BOOL ok = False; + + if (!lp_locking(SNUM(cnum))) + return(True); + + if (count == 0) { + *eclass = ERRDOS; + *ecode = ERRnoaccess; + return False; + } + + if (Files[fnum].can_lock && OPEN_FNUM(fnum) && (Files[fnum].cnum == cnum)) + ok = fcntl_lock(Files[fnum].fd,F_SETLK,offset,count, + (Files[fnum].can_write?F_WRLCK:F_RDLCK)); + + if (!ok) { + *eclass = ERRDOS; + *ecode = ERRlock; + return False; + } + return True; /* Got lock */ +} + + +/**************************************************************************** + utility function called by unlocking requests +****************************************************************************/ +BOOL do_unlock(int fnum,int cnum,uint32 count,uint32 offset,int *eclass,uint32 *ecode) +{ + BOOL ok = False; + + if (!lp_locking(SNUM(cnum))) + return(True); + + if (Files[fnum].can_lock && OPEN_FNUM(fnum) && (Files[fnum].cnum == cnum)) + ok = fcntl_lock(Files[fnum].fd,F_SETLK,offset,count,F_UNLCK); + + if (!ok) { + *eclass = ERRDOS; + *ecode = ERRlock; + return False; + } + return True; /* Did unlock */ +} + +/******************************************************************* + name a share file + ******************************************************************/ +static BOOL share_name(int cnum,struct stat *st,char *name) +{ + strcpy(name,lp_lockdir()); + standard_sub(cnum,name); + trim_string(name,"","/"); + if (!*name) return(False); + name += strlen(name); + + sprintf(name,"/share.%d.%d",(int)st->st_dev,(int)st->st_ino); + return(True); +} + +/******************************************************************* + use the fnum to get the share file name + ******************************************************************/ +static BOOL share_name_fnum(int fnum,char *name) +{ + struct stat st; + if (fstat(Files[fnum].fd,&st) != 0) return(False); + return(share_name(Files[fnum].cnum,&st,name)); +} + + +/******************************************************************* + get the share mode of a file using the fnum + ******************************************************************/ +int get_share_mode_by_fnum(int cnum,int fnum,int *pid) +{ + struct stat sbuf; + if (fstat(Files[fnum].fd,&sbuf) == -1) return(0); + return(get_share_mode(cnum,&sbuf,pid)); +} + +/******************************************************************* + get the share mode of a file using the files name + ******************************************************************/ +int get_share_mode_byname(int cnum,char *fname,int *pid) +{ + struct stat sbuf; + if (stat(fname,&sbuf) == -1) return(0); + return(get_share_mode(cnum,&sbuf,pid)); +} + + +/******************************************************************* +get the share mode of a file +********************************************************************/ +int get_share_mode(int cnum,struct stat *sbuf,int *pid) +{ + pstring fname; + int fd2; + char buf[16]; + int ret; + time_t t; + + *pid = 0; + + if (!share_name(cnum,sbuf,fname)) return(0); + + fd2 = open(fname,O_RDONLY,0); + if (fd2 < 0) return(0); + + if (read(fd2,buf,16) != 16) { + close(fd2); + unlink(fname); + return(0); + } + close(fd2); + + t = IVAL(buf,0); + ret = IVAL(buf,4); + *pid = IVAL(buf,8); + + if (IVAL(buf,12) != LOCKING_VERSION) { + if (!unlink(fname)) DEBUG(2,("Deleted old locking file %s",fname)); + *pid = 0; + return(0); + } + + if (*pid && !process_exists(*pid)) { + ret=0; + *pid = 0; + } + + if (! *pid) unlink(fname); /* XXXXX race, race */ + + if (*pid) + DEBUG(5,("Read share file %s mode 0x%X pid=%d\n",fname,ret,*pid)); + + return(ret); +} + + +/******************************************************************* +del the share mode of a file, if we set it last +********************************************************************/ +void del_share_mode(int fnum) +{ + pstring fname; + int fd2; + char buf[16]; + time_t t=0; + int pid=0; + BOOL del = False; + + if (!share_name_fnum(fnum,fname)) return; + + fd2 = open(fname,O_RDONLY,0); + if (fd2 < 0) return; + if (read(fd2,buf,16) != 16) + del = True; + close(fd2); + + if (!del) { + t = IVAL(buf,0); + pid = IVAL(buf,8); + } + + if (!del) + if (IVAL(buf,12) != LOCKING_VERSION || !pid || !process_exists(pid)) + del = True; + + if (!del && t == Files[fnum].open_time && pid==(int)getpid()) + del = True; + + if (del) { + if (!unlink(fname)) + DEBUG(2,("Deleted share file %s\n",fname)); + else { + DEBUG(3,("Pending delete share file %s\n",fname)); + if (*share_del_pending) DEBUG(0,("Share del clash!\n")); + strcpy(share_del_pending,fname); + } + } +} + + +/******************************************************************* +set the share mode of a file +********************************************************************/ +BOOL set_share_mode(int fnum,int mode) +{ + pstring fname; + int fd2; + char buf[16]; + int pid = (int)getpid(); + + if (!share_name_fnum(fnum,fname)) return(False); + + { + int old_umask = umask(0); + fd2 = open(fname,O_WRONLY|O_CREAT|O_TRUNC,0644); + umask(old_umask); + } + if (fd2 < 0) { + DEBUG(2,("Failed to create share file %s\n",fname)); + return(False); + } + + SIVAL(buf,0,Files[fnum].open_time); + SIVAL(buf,4,mode); + SIVAL(buf,8,pid); + SIVAL(buf,12,LOCKING_VERSION); + + if (write(fd2,buf,16) != 16) { + close(fd2); + unlink(fname); + return(False); + } + + write(fd2,Files[fnum].name,strlen(Files[fnum].name)+1); + + close(fd2); + + DEBUG(3,("Created share file %s with mode 0x%X pid=%d\n",fname,mode,pid)); + + return(True); +} + + +/******************************************************************* +cleanup any stale share files +********************************************************************/ +void clean_share_files(void) +{ + char *lockdir = lp_lockdir(); + void *dir; + char *s; + + if (!*lockdir) return; + + dir = opendir(lockdir); + if (!dir) return; + + while ((s=readdirname(dir))) { + char buf[16]; + int pid; + int fd; + pstring lname; + int dev,inode; + + if (sscanf(s,"share.%d.%d",&dev,&inode)!=2) continue; + + strcpy(lname,lp_lockdir()); + trim_string(lname,NULL,"/"); + strcat(lname,"/"); + strcat(lname,s); + + fd = open(lname,O_RDONLY,0); + if (fd < 0) continue; + + if (read(fd,buf,16) != 16) { + close(fd); + if (!unlink(lname)) + printf("Deleted corrupt share file %s\n",s); + continue; + } + close(fd); + + pid = IVAL(buf,8); + + if (IVAL(buf,12) != LOCKING_VERSION || !process_exists(pid)) { + if (!unlink(lname)) + printf("Deleted stale share file %s\n",s); + } + } + + closedir(dir); +} -- cgit