openldap/servers/slapd/lock.c
1998-08-09 00:43:13 +00:00

65 lines
1.2 KiB
C

/* lock.c - routines to open and apply an advisory lock to a file */
#include <stdio.h>
#include <sys/time.h>
#include <sys/types.h>
#include "portable.h"
#ifdef USE_LOCKF
#include <unistd.h>
#endif
#include <sys/file.h>
#include <sys/param.h>
#include <sys/socket.h>
#include "slap.h"
FILE *
lock_fopen( char *fname, char *type, FILE **lfp )
{
FILE *fp;
char buf[MAXPATHLEN];
/* open the lock file */
strcpy( buf, fname );
strcat( buf, ".lock" );
if ( (*lfp = fopen( buf, "w" )) == NULL ) {
Debug( LDAP_DEBUG_ANY, "could not open \"%s\"\n", buf, 0, 0 );
return( NULL );
}
/* acquire the lock */
#ifdef USE_LOCKF
while ( lockf( fileno( *lfp ), F_LOCK, 0 ) != 0 ) {
#else
while ( flock( fileno( *lfp ), LOCK_EX ) != 0 ) {
#endif
; /* NULL */
}
/* open the log file */
if ( (fp = fopen( fname, type )) == NULL ) {
Debug( LDAP_DEBUG_ANY, "could not open \"%s\"\n", fname, 0, 0 );
#ifdef USE_LOCKF
lockf( fileno( *lfp ), F_ULOCK, 0 );
#else
flock( fileno( *lfp ), LOCK_UN );
#endif
return( NULL );
}
return( fp );
}
int
lock_fclose( FILE *fp, FILE *lfp )
{
/* unlock */
#ifdef USE_LOCKF
lockf( fileno( lfp ), F_ULOCK, 0 );
#else
flock( fileno( lfp ), LOCK_UN );
#endif
fclose( lfp );
return( fclose( fp ) );
}