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/* $OpenLDAP: pkg/ldap/servers/slurpd/lock.c,v 1.10.8.2 2000/06/13 17:57:41 kurt Exp $ */
/*
* Copyright (c) 1996 Regents of the University of Michigan.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that this notice is preserved and that due credit is given
* to the University of Michigan at Ann Arbor. The name of the University
* may not be used to endorse or promote products derived from this
* software without specific prior written permission. This software
* is provided ``as is'' without express or implied warranty.
*/
/*
* lock.c - routines to open and apply an advisory lock to a file
*/
#include "portable.h"
#include <stdio.h>
#include <ac/param.h>
#include <ac/string.h>
#include <ac/socket.h>
#include <ac/time.h>
#include <ac/unistd.h>
#ifdef HAVE_SYS_FILE_H
#include <sys/file.h>
#endif
#include "slurp.h"
FILE *
lock_fopen(
const char *fname,
const char *type,
FILE **lfp
)
{
FILE *fp;
char buf[MAXPATHLEN];
/* open the lock file */
snprintf(buf,MAXPATHLEN,"%s.lock",fname);
if ( (*lfp = fopen( buf, "w" )) == NULL ) {
Debug( LDAP_DEBUG_ANY,
"Error: could not open \"%s\"\n", buf, 0, 0 );
return( NULL );
}
/* acquire the lock */
ldap_lockf( fileno(*lfp) );
/* open the log file */
if ( (fp = fopen( fname, type )) == NULL ) {
Debug( LDAP_DEBUG_ANY,
"Error: could not open \"%s\"\n", fname, 0, 0 );
ldap_unlockf( fileno(*lfp) );
fclose( *lfp );
*lfp = NULL;
return( NULL );
}
return( fp );
}
int
lock_fclose(
FILE *fp,
FILE *lfp
)
{
/* unlock */
ldap_unlockf( fileno(lfp) );
fclose( lfp );
return( fclose( fp ) );
}
/*
* Apply an advisory lock on a file. Just calls lock_fopen()
*/
int
acquire_lock(
const char *file,
FILE **rfp,
FILE **lfp
)
{
if (( *rfp = lock_fopen( file, "r+", lfp )) == NULL ) {
Debug( LDAP_DEBUG_ANY,
"Error: acquire_lock(%ld): Could not acquire lock on \"%s\"\n",
(long) getpid(), file, 0);
return( -1 );
}
return( 0 );
}
/*
* Relinquish a lock on a file. Calls lock_fclose() and also removes the
* lock file.
*/
int
relinquish_lock(
const char *file,
FILE *rfp,
FILE *lfp
)
{
if ( lock_fclose( rfp, lfp ) == EOF ) {
Debug( LDAP_DEBUG_ANY,
"Error: relinquish_lock (%ld): Error closing \"%s\"\n",
(long) getpid(), file, 0 );
return( -1 );
}
return( 0 );
}
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