michael@0: /*-
michael@0:  * Copyright (c) 1991, 1993
michael@0:  *	The Regents of the University of California.  All rights reserved.
michael@0:  *
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  * 1. Redistributions of source code must retain the above copyright
michael@0:  *    notice, this list of conditions and the following disclaimer.
michael@0:  * 2. Redistributions in binary form must reproduce the above copyright
michael@0:  *    notice, this list of conditions and the following disclaimer in the
michael@0:  *    documentation and/or other materials provided with the distribution.
michael@0:  * 3. ***REMOVED*** - see 
michael@0:  *    ftp://ftp.cs.berkeley.edu/pub/4bsd/README.Impt.License.Change
michael@0:  * 4. Neither the name of the University nor the names of its contributors
michael@0:  *    may be used to endorse or promote products derived from this software
michael@0:  *    without specific prior written permission.
michael@0:  *
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
michael@0:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
michael@0:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
michael@0:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
michael@0:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
michael@0:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
michael@0:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
michael@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
michael@0:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
michael@0:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
michael@0:  * SUCH DAMAGE.
michael@0:  */
michael@0: 
michael@0: #if defined(LIBC_SCCS) && !defined(lint)
michael@0: static char sccsid[] = "@(#)db.c	8.4 (Berkeley) 2/21/94";
michael@0: #endif /* LIBC_SCCS and not lint */
michael@0: 
michael@0: #ifndef __DBINTERFACE_PRIVATE
michael@0: #define __DBINTERFACE_PRIVATE
michael@0: #endif
michael@0: #ifdef macintosh
michael@0: #include <unix.h>
michael@0: #else
michael@0: #include <sys/types.h>
michael@0: #endif
michael@0: 
michael@0: #include <errno.h>
michael@0: #include <fcntl.h>
michael@0: #include <stddef.h>
michael@0: #include <stdio.h>
michael@0: 
michael@0: #include "mcom_db.h"
michael@0: 
michael@0: /* a global flag that locks closed all databases */
michael@0: int all_databases_locked_closed = 0;
michael@0: 
michael@0: /* set or unset a global lock flag to disable the
michael@0:  * opening of any DBM file
michael@0:  */
michael@0: void 
michael@0: dbSetOrClearDBLock(DBLockFlagEnum type)
michael@0: {
michael@0: 	if(type == LockOutDatabase)
michael@0: 		all_databases_locked_closed = 1;
michael@0: 	else
michael@0: 		all_databases_locked_closed = 0;
michael@0: }
michael@0: 
michael@0: DB *
michael@0: dbopen(const char *fname, int flags,int mode, DBTYPE type, const void *openinfo)
michael@0: {
michael@0: 
michael@0: 	/* lock out all file databases.  Let in-memory databases through
michael@0: 	 */
michael@0: 	if(all_databases_locked_closed && fname)
michael@0: 	  {
michael@0: 		errno = EINVAL;
michael@0: 		return(NULL);
michael@0: 	  }
michael@0: 
michael@0: #define	DB_FLAGS	(DB_LOCK | DB_SHMEM | DB_TXN)
michael@0: 
michael@0: 
michael@0: #if 0  /* most systems don't have EXLOCK and SHLOCK */
michael@0: #define	USE_OPEN_FLAGS							\
michael@0: 	(O_CREAT | O_EXCL | O_EXLOCK | O_NONBLOCK | O_RDONLY |		\
michael@0: 	 O_RDWR | O_SHLOCK | O_TRUNC)
michael@0: #else
michael@0: #define	USE_OPEN_FLAGS							\
michael@0: 	(O_CREAT | O_EXCL  | O_RDONLY |		\
michael@0: 	 O_RDWR | O_TRUNC)
michael@0: #endif
michael@0: 
michael@0: 	if ((flags & ~(USE_OPEN_FLAGS | DB_FLAGS)) == 0)
michael@0: 		switch (type) {
michael@0: /* we don't need btree and recno right now */	
michael@0: #if 0
michael@0: 		case DB_BTREE:
michael@0: 			return (__bt_open(fname, flags & USE_OPEN_FLAGS,
michael@0: 			    mode, openinfo, flags & DB_FLAGS));
michael@0: 		case DB_RECNO:
michael@0: 			return (__rec_open(fname, flags & USE_OPEN_FLAGS,
michael@0: 			    mode, openinfo, flags & DB_FLAGS));
michael@0: #endif
michael@0: 
michael@0: 		case DB_HASH:
michael@0: 			return (__hash_open(fname, flags & USE_OPEN_FLAGS,
michael@0: 			    mode, (const HASHINFO *)openinfo, flags & DB_FLAGS));
michael@0: 		default:
michael@0: 			break;
michael@0: 		}
michael@0: 	errno = EINVAL;
michael@0: 	return (NULL);
michael@0: }
michael@0: 
michael@0: static int
michael@0: __dberr()
michael@0: {
michael@0: 	return (RET_ERROR);
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * __DBPANIC -- Stop.
michael@0:  *
michael@0:  * Parameters:
michael@0:  *	dbp:	pointer to the DB structure.
michael@0:  */
michael@0: void
michael@0: __dbpanic(DB *dbp)
michael@0: {
michael@0: 	/* The only thing that can succeed is a close. */
michael@0: 	dbp->del = (int (*)(const struct __db *, const DBT *, uint))__dberr;
michael@0: 	dbp->fd = (int (*)(const struct __db *))__dberr;
michael@0: 	dbp->get = (int (*)(const struct __db *, const DBT *, DBT *, uint))__dberr;
michael@0: 	dbp->put = (int (*)(const struct __db *, DBT *, const DBT *, uint))__dberr;
michael@0: 	dbp->seq = (int (*)(const struct __db *, DBT *, DBT *, uint))__dberr;
michael@0: 	dbp->sync = (int (*)(const struct __db *, uint))__dberr;
michael@0: }