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/*
* Copyright (c) 2000 Silicon Graphics, Inc. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
* Further, this software is distributed without any warranty that it is
* free of the rightful claim of any third person regarding infringement
* or the like. Any license provided herein, whether implied or
* otherwise, applies only to this software file. Patent licenses, if
* any, provided herein do not apply to combinations of this program with
* other software, or any other product whatsoever.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
* Mountain View, CA 94043, or:
*
* http://www.sgi.com
*
* For further information regarding this notice, see:
*
* http://oss.sgi.com/projects/GenInfo/NoticeExplan/
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/param.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <sys/sysmacros.h>
#include <string.h> /* memset, strerror */
extern int errno;
#ifndef EFSEXCLWR
#define EFSEXCLWR 503
#endif
/*
* String containing the last system call.
*
*/
char Fl_syscall_str[128];
static char errmsg[256];
/***********************************************************************
*
* Test interface to the fcntl system call.
* It will loop if the LOCK_NB flags is NOT set.
***********************************************************************/
int
file_lock(fd, flags, errormsg)
int fd;
int flags;
char **errormsg;
{
register int cmd, ret;
struct flock flocks;
memset(&flocks, 0, sizeof(struct flock));
if (flags&LOCK_NB)
cmd = F_SETLK;
else
cmd = F_SETLKW;
flocks.l_whence = 0;
flocks.l_start = 0;
flocks.l_len = 0;
if (flags&LOCK_UN)
flocks.l_type = F_UNLCK;
else if (flags&LOCK_EX)
flocks.l_type = F_WRLCK;
else if (flags&LOCK_SH)
flocks.l_type = F_RDLCK;
else {
errno = EINVAL;
if ( errormsg != NULL ) {
sprintf(errmsg,
"Programmer error, called file_lock with in valid flags\n");
*errormsg = errmsg;
}
return -1;
}
sprintf(Fl_syscall_str,
"fcntl(%d, %d, &flocks): type:%d whence:%d, start:%lld len:%lld\n",
fd, cmd, flocks.l_type, flocks.l_whence,
(long long)flocks.l_start, (long long)flocks.l_len);
while (1) {
ret = fcntl(fd, cmd, &flocks);
if ( ret < 0 ) {
if ( cmd == F_SETLK )
switch (errno) {
/* these errors are okay */
case EACCES: /* Permission denied */
case EINTR: /* interrupted system call */
#ifdef EFILESH
case EFILESH: /* file shared */
#endif
case EFSEXCLWR: /* File is write protected */
continue; /* retry getting lock */
}
if ( errormsg != NULL ) {
sprintf(errmsg, "fcntl(%d, %d, &flocks): errno:%d %s\n",
fd, cmd, errno, strerror(errno));
*errormsg = errmsg;
}
return -1;
}
break;
}
return ret;
} /* end of file_lock */
/***********************************************************************
*
* Test interface to the fcntl system call.
* It will loop if the LOCK_NB flags is NOT set.
***********************************************************************/
int
record_lock(fd, flags, start, len, errormsg)
int fd;
int flags;
int start;
int len;
char **errormsg;
{
register int cmd, ret;
struct flock flocks;
memset(&flocks, 0, sizeof(struct flock));
if (flags&LOCK_NB)
cmd = F_SETLK;
else
cmd = F_SETLKW;
flocks.l_whence = 0;
flocks.l_start = start;
flocks.l_len = len;
if (flags&LOCK_UN)
flocks.l_type = F_UNLCK;
else if (flags&LOCK_EX)
flocks.l_type = F_WRLCK;
else if (flags&LOCK_SH)
flocks.l_type = F_RDLCK;
else {
errno = EINVAL;
if ( errormsg != NULL ) {
sprintf(errmsg,
"Programmer error, called record_lock with in valid flags\n");
*errormsg = errmsg;
}
return -1;
}
sprintf(Fl_syscall_str,
"fcntl(%d, %d, &flocks): type:%d whence:%d, start:%lld len:%lld\n",
fd, cmd, flocks.l_type, flocks.l_whence,
(long long)flocks.l_start, (long long)flocks.l_len);
while (1) {
ret = fcntl(fd, cmd, &flocks);
if ( ret < 0 ) {
if ( cmd == F_SETLK )
switch (errno) {
/* these errors are okay */
case EACCES: /* Permission denied */
case EINTR: /* interrupted system call */
#ifdef EFILESH
case EFILESH: /* file shared */
#endif
case EFSEXCLWR: /* File is write protected */
continue; /* retry getting lock */
}
if ( errormsg != NULL ) {
sprintf(errmsg, "fcntl(%d, %d, &flocks): errno:%d %s\n",
fd, cmd, errno, strerror(errno));
*errormsg = errmsg;
}
return -1;
}
break;
}
return ret;
} /* end of record_lock */