17c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
27c478bd9Sstevel@tonic-gate 
37c478bd9Sstevel@tonic-gate /*-
47c478bd9Sstevel@tonic-gate  * Copyright (c) 1990, 1993, 1994
57c478bd9Sstevel@tonic-gate  *	The Regents of the University of California.  All rights reserved.
67c478bd9Sstevel@tonic-gate  *
77c478bd9Sstevel@tonic-gate  * This code is derived from software contributed to Berkeley by
87c478bd9Sstevel@tonic-gate  * Mike Olson.
97c478bd9Sstevel@tonic-gate  *
107c478bd9Sstevel@tonic-gate  * Redistribution and use in source and binary forms, with or without
117c478bd9Sstevel@tonic-gate  * modification, are permitted provided that the following conditions
127c478bd9Sstevel@tonic-gate  * are met:
137c478bd9Sstevel@tonic-gate  * 1. Redistributions of source code must retain the above copyright
147c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer.
157c478bd9Sstevel@tonic-gate  * 2. Redistributions in binary form must reproduce the above copyright
167c478bd9Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer in the
177c478bd9Sstevel@tonic-gate  *    documentation and/or other materials provided with the distribution.
187c478bd9Sstevel@tonic-gate  * 3. All advertising materials mentioning features or use of this software
197c478bd9Sstevel@tonic-gate  *    must display the following acknowledgement:
207c478bd9Sstevel@tonic-gate  *	This product includes software developed by the University of
217c478bd9Sstevel@tonic-gate  *	California, Berkeley and its contributors.
227c478bd9Sstevel@tonic-gate  * 4. Neither the name of the University nor the names of its contributors
237c478bd9Sstevel@tonic-gate  *    may be used to endorse or promote products derived from this software
247c478bd9Sstevel@tonic-gate  *    without specific prior written permission.
257c478bd9Sstevel@tonic-gate  *
267c478bd9Sstevel@tonic-gate  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
277c478bd9Sstevel@tonic-gate  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
287c478bd9Sstevel@tonic-gate  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
297c478bd9Sstevel@tonic-gate  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
307c478bd9Sstevel@tonic-gate  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
317c478bd9Sstevel@tonic-gate  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
327c478bd9Sstevel@tonic-gate  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
337c478bd9Sstevel@tonic-gate  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
347c478bd9Sstevel@tonic-gate  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
357c478bd9Sstevel@tonic-gate  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
367c478bd9Sstevel@tonic-gate  * SUCH DAMAGE.
377c478bd9Sstevel@tonic-gate  */
387c478bd9Sstevel@tonic-gate 
397c478bd9Sstevel@tonic-gate #if defined(LIBC_SCCS) && !defined(lint)
407c478bd9Sstevel@tonic-gate static char sccsid[] = "@(#)bt_open.c	8.11 (Berkeley) 11/2/95";
417c478bd9Sstevel@tonic-gate #endif /* LIBC_SCCS and not lint */
427c478bd9Sstevel@tonic-gate 
437c478bd9Sstevel@tonic-gate /*
447c478bd9Sstevel@tonic-gate  * Implementation of btree access method for 4.4BSD.
457c478bd9Sstevel@tonic-gate  *
467c478bd9Sstevel@tonic-gate  * The design here was originally based on that of the btree access method
477c478bd9Sstevel@tonic-gate  * used in the Postgres database system at UC Berkeley.  This implementation
487c478bd9Sstevel@tonic-gate  * is wholly independent of the Postgres code.
497c478bd9Sstevel@tonic-gate  */
507c478bd9Sstevel@tonic-gate 
517c478bd9Sstevel@tonic-gate #include <sys/param.h>
527c478bd9Sstevel@tonic-gate #include <sys/stat.h>
537c478bd9Sstevel@tonic-gate 
547c478bd9Sstevel@tonic-gate #include <errno.h>
557c478bd9Sstevel@tonic-gate #include <fcntl.h>
567c478bd9Sstevel@tonic-gate #include <limits.h>
577c478bd9Sstevel@tonic-gate #include <signal.h>
587c478bd9Sstevel@tonic-gate #include <stdio.h>
597c478bd9Sstevel@tonic-gate #include <stdlib.h>
607c478bd9Sstevel@tonic-gate #include <string.h>
617c478bd9Sstevel@tonic-gate #include <unistd.h>
627c478bd9Sstevel@tonic-gate 
637c478bd9Sstevel@tonic-gate #include "db-int.h"
647c478bd9Sstevel@tonic-gate #include "btree.h"
657c478bd9Sstevel@tonic-gate 
6656a424ccSmp #ifdef DEBUG
677c478bd9Sstevel@tonic-gate #undef	MINPSIZE
687c478bd9Sstevel@tonic-gate #define	MINPSIZE	128
697c478bd9Sstevel@tonic-gate #endif
707c478bd9Sstevel@tonic-gate 
717c478bd9Sstevel@tonic-gate static int byteorder __P((void));
727c478bd9Sstevel@tonic-gate static int nroot __P((BTREE *));
737c478bd9Sstevel@tonic-gate static int tmp __P((void));
747c478bd9Sstevel@tonic-gate 
757c478bd9Sstevel@tonic-gate /*
767c478bd9Sstevel@tonic-gate  * __BT_OPEN -- Open a btree.
777c478bd9Sstevel@tonic-gate  *
787c478bd9Sstevel@tonic-gate  * Creates and fills a DB struct, and calls the routine that actually
797c478bd9Sstevel@tonic-gate  * opens the btree.
807c478bd9Sstevel@tonic-gate  *
817c478bd9Sstevel@tonic-gate  * Parameters:
827c478bd9Sstevel@tonic-gate  *	fname:	filename (NULL for in-memory trees)
837c478bd9Sstevel@tonic-gate  *	flags:	open flag bits
847c478bd9Sstevel@tonic-gate  *	mode:	open permission bits
857c478bd9Sstevel@tonic-gate  *	b:	BTREEINFO pointer
867c478bd9Sstevel@tonic-gate  *
877c478bd9Sstevel@tonic-gate  * Returns:
887c478bd9Sstevel@tonic-gate  *	NULL on failure, pointer to DB on success.
897c478bd9Sstevel@tonic-gate  *
907c478bd9Sstevel@tonic-gate  */
917c478bd9Sstevel@tonic-gate DB *
__bt_open(fname,flags,mode,openinfo,dflags)927c478bd9Sstevel@tonic-gate __bt_open(fname, flags, mode, openinfo, dflags)
937c478bd9Sstevel@tonic-gate 	const char *fname;
947c478bd9Sstevel@tonic-gate 	int flags, mode, dflags;
957c478bd9Sstevel@tonic-gate 	const BTREEINFO *openinfo;
967c478bd9Sstevel@tonic-gate {
977c478bd9Sstevel@tonic-gate 	struct stat sb;
987c478bd9Sstevel@tonic-gate 	BTMETA m;
997c478bd9Sstevel@tonic-gate 	BTREE *t;
1007c478bd9Sstevel@tonic-gate 	BTREEINFO b;
1017c478bd9Sstevel@tonic-gate 	DB *dbp;
1027c478bd9Sstevel@tonic-gate 	db_pgno_t ncache;
1037c478bd9Sstevel@tonic-gate 	ssize_t nr;
1047c478bd9Sstevel@tonic-gate 	int machine_lorder;
1057c478bd9Sstevel@tonic-gate 
1067c478bd9Sstevel@tonic-gate 	t = NULL;
1077c478bd9Sstevel@tonic-gate 
1087c478bd9Sstevel@tonic-gate 	/*
1097c478bd9Sstevel@tonic-gate 	 * Intention is to make sure all of the user's selections are okay
1107c478bd9Sstevel@tonic-gate 	 * here and then use them without checking.  Can't be complete, since
1117c478bd9Sstevel@tonic-gate 	 * we don't know the right page size, lorder or flags until the backing
1127c478bd9Sstevel@tonic-gate 	 * file is opened.  Also, the file's page size can cause the cachesize
1137c478bd9Sstevel@tonic-gate 	 * to change.
1147c478bd9Sstevel@tonic-gate 	 */
1157c478bd9Sstevel@tonic-gate 	machine_lorder = byteorder();
1167c478bd9Sstevel@tonic-gate 	if (openinfo) {
1177c478bd9Sstevel@tonic-gate 		b = *openinfo;
1187c478bd9Sstevel@tonic-gate 
1197c478bd9Sstevel@tonic-gate 		/* Flags: R_DUP. */
1207c478bd9Sstevel@tonic-gate 		if (b.flags & ~(R_DUP))
1217c478bd9Sstevel@tonic-gate 			goto einval;
1227c478bd9Sstevel@tonic-gate 
1237c478bd9Sstevel@tonic-gate 		/*
1247c478bd9Sstevel@tonic-gate 		 * Page size must be indx_t aligned and >= MINPSIZE.  Default
1257c478bd9Sstevel@tonic-gate 		 * page size is set farther on, based on the underlying file
1267c478bd9Sstevel@tonic-gate 		 * transfer size.
1277c478bd9Sstevel@tonic-gate 		 */
1287c478bd9Sstevel@tonic-gate 		if (b.psize &&
1297c478bd9Sstevel@tonic-gate 		    (b.psize < MINPSIZE || b.psize > MAX_PAGE_OFFSET + 1 ||
13056a424ccSmp 		    b.psize & (sizeof(indx_t) - 1)))
1317c478bd9Sstevel@tonic-gate 			goto einval;
1327c478bd9Sstevel@tonic-gate 
1337c478bd9Sstevel@tonic-gate 		/* Minimum number of keys per page; absolute minimum is 2. */
1347c478bd9Sstevel@tonic-gate 		if (b.minkeypage) {
1357c478bd9Sstevel@tonic-gate 			if (b.minkeypage < 2)
1367c478bd9Sstevel@tonic-gate 				goto einval;
1377c478bd9Sstevel@tonic-gate 		} else
1387c478bd9Sstevel@tonic-gate 			b.minkeypage = DEFMINKEYPAGE;
1397c478bd9Sstevel@tonic-gate 
1407c478bd9Sstevel@tonic-gate 		/* If no comparison, use default comparison and prefix. */
1417c478bd9Sstevel@tonic-gate 		if (b.compare == NULL) {
1427c478bd9Sstevel@tonic-gate 			b.compare = __bt_defcmp;
1437c478bd9Sstevel@tonic-gate 			if (b.prefix == NULL)
1447c478bd9Sstevel@tonic-gate 				b.prefix = __bt_defpfx;
1457c478bd9Sstevel@tonic-gate 		}
1467c478bd9Sstevel@tonic-gate 
1477c478bd9Sstevel@tonic-gate 		if (b.lorder == 0)
1487c478bd9Sstevel@tonic-gate 			b.lorder = machine_lorder;
1497c478bd9Sstevel@tonic-gate 	} else {
1507c478bd9Sstevel@tonic-gate 		b.compare = __bt_defcmp;
1517c478bd9Sstevel@tonic-gate 		b.cachesize = 0;
1527c478bd9Sstevel@tonic-gate 		b.flags = 0;
1537c478bd9Sstevel@tonic-gate 		b.lorder = machine_lorder;
1547c478bd9Sstevel@tonic-gate 		b.minkeypage = DEFMINKEYPAGE;
1557c478bd9Sstevel@tonic-gate 		b.prefix = __bt_defpfx;
1567c478bd9Sstevel@tonic-gate 		b.psize = 0;
1577c478bd9Sstevel@tonic-gate 	}
1587c478bd9Sstevel@tonic-gate 
1597c478bd9Sstevel@tonic-gate 	/* Check for the ubiquitous PDP-11. */
1607c478bd9Sstevel@tonic-gate 	if (b.lorder != DB_BIG_ENDIAN && b.lorder != DB_LITTLE_ENDIAN)
1617c478bd9Sstevel@tonic-gate 		goto einval;
1627c478bd9Sstevel@tonic-gate 
1637c478bd9Sstevel@tonic-gate 	/* Allocate and initialize DB and BTREE structures. */
1647c478bd9Sstevel@tonic-gate 	if ((t = (BTREE *)malloc(sizeof(BTREE))) == NULL)
1657c478bd9Sstevel@tonic-gate 		goto err;
1667c478bd9Sstevel@tonic-gate 	memset(t, 0, sizeof(BTREE));
1677c478bd9Sstevel@tonic-gate 	t->bt_fd = -1;			/* Don't close unopened fd on error. */
1687c478bd9Sstevel@tonic-gate 	t->bt_lorder = b.lorder;
1697c478bd9Sstevel@tonic-gate 	t->bt_order = NOT;
1707c478bd9Sstevel@tonic-gate 	t->bt_cmp = b.compare;
1717c478bd9Sstevel@tonic-gate 	t->bt_pfx = b.prefix;
1727c478bd9Sstevel@tonic-gate 	t->bt_rfd = -1;
1737c478bd9Sstevel@tonic-gate 
1747c478bd9Sstevel@tonic-gate 	if ((t->bt_dbp = dbp = (DB *)malloc(sizeof(DB))) == NULL)
1757c478bd9Sstevel@tonic-gate 		goto err;
1767c478bd9Sstevel@tonic-gate 	memset(t->bt_dbp, 0, sizeof(DB));
1777c478bd9Sstevel@tonic-gate 	if (t->bt_lorder != machine_lorder)
1787c478bd9Sstevel@tonic-gate 		F_SET(t, B_NEEDSWAP);
1797c478bd9Sstevel@tonic-gate 
1807c478bd9Sstevel@tonic-gate 	dbp->type = DB_BTREE;
1817c478bd9Sstevel@tonic-gate 	dbp->internal = t;
1827c478bd9Sstevel@tonic-gate 	dbp->close = __bt_close;
1837c478bd9Sstevel@tonic-gate 	dbp->del = __bt_delete;
1847c478bd9Sstevel@tonic-gate 	dbp->fd = __bt_fd;
1857c478bd9Sstevel@tonic-gate 	dbp->get = __bt_get;
1867c478bd9Sstevel@tonic-gate 	dbp->put = __bt_put;
1877c478bd9Sstevel@tonic-gate 	dbp->seq = __bt_seq;
1887c478bd9Sstevel@tonic-gate 	dbp->sync = __bt_sync;
1897c478bd9Sstevel@tonic-gate 
1907c478bd9Sstevel@tonic-gate 	/*
1917c478bd9Sstevel@tonic-gate 	 * If no file name was supplied, this is an in-memory btree and we
1927c478bd9Sstevel@tonic-gate 	 * open a backing temporary file.  Otherwise, it's a disk-based tree.
1937c478bd9Sstevel@tonic-gate 	 */
1947c478bd9Sstevel@tonic-gate 	if (fname) {
1957c478bd9Sstevel@tonic-gate 		switch (flags & O_ACCMODE) {
1967c478bd9Sstevel@tonic-gate 		case O_RDONLY:
1977c478bd9Sstevel@tonic-gate 			F_SET(t, B_RDONLY);
1987c478bd9Sstevel@tonic-gate 			break;
1997c478bd9Sstevel@tonic-gate 		case O_RDWR:
2007c478bd9Sstevel@tonic-gate 			break;
2017c478bd9Sstevel@tonic-gate 		case O_WRONLY:
2027c478bd9Sstevel@tonic-gate 		default:
2037c478bd9Sstevel@tonic-gate 			goto einval;
2047c478bd9Sstevel@tonic-gate 		}
2057c478bd9Sstevel@tonic-gate 
2067c478bd9Sstevel@tonic-gate 		if ((t->bt_fd = open(fname, flags | O_BINARY, mode)) < 0)
2077c478bd9Sstevel@tonic-gate 			goto err;
2087c478bd9Sstevel@tonic-gate 
2097c478bd9Sstevel@tonic-gate 	} else {
2107c478bd9Sstevel@tonic-gate 		if ((flags & O_ACCMODE) != O_RDWR)
2117c478bd9Sstevel@tonic-gate 			goto einval;
2127c478bd9Sstevel@tonic-gate 		if ((t->bt_fd = tmp()) == -1)
2137c478bd9Sstevel@tonic-gate 			goto err;
2147c478bd9Sstevel@tonic-gate 		F_SET(t, B_INMEM);
2157c478bd9Sstevel@tonic-gate 	}
2167c478bd9Sstevel@tonic-gate 
2177c478bd9Sstevel@tonic-gate 	if (fcntl(t->bt_fd, F_SETFD, 1) == -1)
2187c478bd9Sstevel@tonic-gate 		goto err;
2197c478bd9Sstevel@tonic-gate 
2207c478bd9Sstevel@tonic-gate 	if (fstat(t->bt_fd, &sb))
2217c478bd9Sstevel@tonic-gate 		goto err;
2227c478bd9Sstevel@tonic-gate 	if (sb.st_size) {
2237c478bd9Sstevel@tonic-gate 		if ((nr = read(t->bt_fd, &m, sizeof(BTMETA))) < 0)
2247c478bd9Sstevel@tonic-gate 			goto err;
2257c478bd9Sstevel@tonic-gate 		if (nr != sizeof(BTMETA))
2267c478bd9Sstevel@tonic-gate 			goto eftype;
2277c478bd9Sstevel@tonic-gate 
2287c478bd9Sstevel@tonic-gate 		/*
2297c478bd9Sstevel@tonic-gate 		 * Read in the meta-data.  This can change the notion of what
2307c478bd9Sstevel@tonic-gate 		 * the lorder, page size and flags are, and, when the page size
2317c478bd9Sstevel@tonic-gate 		 * changes, the cachesize value can change too.  If the user
2327c478bd9Sstevel@tonic-gate 		 * specified the wrong byte order for an existing database, we
2337c478bd9Sstevel@tonic-gate 		 * don't bother to return an error, we just clear the NEEDSWAP
2347c478bd9Sstevel@tonic-gate 		 * bit.
2357c478bd9Sstevel@tonic-gate 		 */
2367c478bd9Sstevel@tonic-gate 		if (m.magic == BTREEMAGIC)
2377c478bd9Sstevel@tonic-gate 			F_CLR(t, B_NEEDSWAP);
2387c478bd9Sstevel@tonic-gate 		else {
2397c478bd9Sstevel@tonic-gate 			F_SET(t, B_NEEDSWAP);
2407c478bd9Sstevel@tonic-gate 			M_32_SWAP(m.magic);
2417c478bd9Sstevel@tonic-gate 			M_32_SWAP(m.version);
2427c478bd9Sstevel@tonic-gate 			M_32_SWAP(m.psize);
2437c478bd9Sstevel@tonic-gate 			M_32_SWAP(m.free);
2447c478bd9Sstevel@tonic-gate 			M_32_SWAP(m.nrecs);
2457c478bd9Sstevel@tonic-gate 			M_32_SWAP(m.flags);
2467c478bd9Sstevel@tonic-gate 		}
2477c478bd9Sstevel@tonic-gate 		if (m.magic != BTREEMAGIC || m.version != BTREEVERSION)
2487c478bd9Sstevel@tonic-gate 			goto eftype;
2497c478bd9Sstevel@tonic-gate 		if (m.psize < MINPSIZE || m.psize > MAX_PAGE_OFFSET + 1 ||
25056a424ccSmp 		    m.psize & (sizeof(indx_t) - 1))
2517c478bd9Sstevel@tonic-gate 			goto eftype;
2527c478bd9Sstevel@tonic-gate 		if (m.flags & ~SAVEMETA)
2537c478bd9Sstevel@tonic-gate 			goto eftype;
2547c478bd9Sstevel@tonic-gate 		b.psize = m.psize;
2557c478bd9Sstevel@tonic-gate 		F_SET(t, m.flags);
2567c478bd9Sstevel@tonic-gate 		t->bt_free = m.free;
2577c478bd9Sstevel@tonic-gate 		t->bt_nrecs = m.nrecs;
2587c478bd9Sstevel@tonic-gate 	} else {
2597c478bd9Sstevel@tonic-gate 		/*
2607c478bd9Sstevel@tonic-gate 		 * Set the page size to the best value for I/O to this file.
2617c478bd9Sstevel@tonic-gate 		 * Don't overflow the page offset type.
2627c478bd9Sstevel@tonic-gate 		 */
2637c478bd9Sstevel@tonic-gate 		if (b.psize == 0) {
2647c478bd9Sstevel@tonic-gate 			b.psize = sb.st_blksize;
2657c478bd9Sstevel@tonic-gate 			if (b.psize < MINPSIZE)
2667c478bd9Sstevel@tonic-gate 				b.psize = MINPSIZE;
2677c478bd9Sstevel@tonic-gate 			if (b.psize > MAX_PAGE_OFFSET + 1)
2687c478bd9Sstevel@tonic-gate 				b.psize = MAX_PAGE_OFFSET + 1;
2697c478bd9Sstevel@tonic-gate 		}
2707c478bd9Sstevel@tonic-gate 
2717c478bd9Sstevel@tonic-gate 		/* Set flag if duplicates permitted. */
2727c478bd9Sstevel@tonic-gate 		if (!(b.flags & R_DUP))
2737c478bd9Sstevel@tonic-gate 			F_SET(t, B_NODUPS);
2747c478bd9Sstevel@tonic-gate 
2757c478bd9Sstevel@tonic-gate 		t->bt_free = P_INVALID;
2767c478bd9Sstevel@tonic-gate 		t->bt_nrecs = 0;
2777c478bd9Sstevel@tonic-gate 		F_SET(t, B_METADIRTY);
2787c478bd9Sstevel@tonic-gate 	}
2797c478bd9Sstevel@tonic-gate 
2807c478bd9Sstevel@tonic-gate 	t->bt_psize = b.psize;
2817c478bd9Sstevel@tonic-gate 
2827c478bd9Sstevel@tonic-gate 	/* Set the cache size; must be a multiple of the page size. */
28356a424ccSmp 	if (b.cachesize && b.cachesize & (b.psize - 1))
28456a424ccSmp 		b.cachesize += (~b.cachesize & (b.psize - 1)) + 1;
2857c478bd9Sstevel@tonic-gate 	if (b.cachesize < b.psize * MINCACHE)
2867c478bd9Sstevel@tonic-gate 		b.cachesize = b.psize * MINCACHE;
2877c478bd9Sstevel@tonic-gate 
2887c478bd9Sstevel@tonic-gate 	/* Calculate number of pages to cache. */
2897c478bd9Sstevel@tonic-gate 	ncache = (b.cachesize + t->bt_psize - 1) / t->bt_psize;
2907c478bd9Sstevel@tonic-gate 
2917c478bd9Sstevel@tonic-gate 	/*
2927c478bd9Sstevel@tonic-gate 	 * The btree data structure requires that at least two keys can fit on
2937c478bd9Sstevel@tonic-gate 	 * a page, but other than that there's no fixed requirement.  The user
2947c478bd9Sstevel@tonic-gate 	 * specified a minimum number per page, and we translated that into the
2957c478bd9Sstevel@tonic-gate 	 * number of bytes a key/data pair can use before being placed on an
2967c478bd9Sstevel@tonic-gate 	 * overflow page.  This calculation includes the page header, the size
2977c478bd9Sstevel@tonic-gate 	 * of the index referencing the leaf item and the size of the leaf item
2987c478bd9Sstevel@tonic-gate 	 * structure.  Also, don't let the user specify a minkeypage such that
2997c478bd9Sstevel@tonic-gate 	 * a key/data pair won't fit even if both key and data are on overflow
3007c478bd9Sstevel@tonic-gate 	 * pages.
3017c478bd9Sstevel@tonic-gate 	 */
3027c478bd9Sstevel@tonic-gate 	t->bt_ovflsize = (t->bt_psize - BTDATAOFF) / b.minkeypage -
3037c478bd9Sstevel@tonic-gate 	    (sizeof(indx_t) + NBLEAFDBT(0, 0));
3047c478bd9Sstevel@tonic-gate 	if (t->bt_ovflsize < NBLEAFDBT(NOVFLSIZE, NOVFLSIZE) + sizeof(indx_t))
3057c478bd9Sstevel@tonic-gate 		t->bt_ovflsize =
3067c478bd9Sstevel@tonic-gate 		    NBLEAFDBT(NOVFLSIZE, NOVFLSIZE) + sizeof(indx_t);
3077c478bd9Sstevel@tonic-gate 
3087c478bd9Sstevel@tonic-gate 	/* Initialize the buffer pool. */
3097c478bd9Sstevel@tonic-gate 	if ((t->bt_mp =
3107c478bd9Sstevel@tonic-gate 	    mpool_open(NULL, t->bt_fd, t->bt_psize, ncache)) == NULL)
3117c478bd9Sstevel@tonic-gate 		goto err;
3127c478bd9Sstevel@tonic-gate 	if (!F_ISSET(t, B_INMEM))
3137c478bd9Sstevel@tonic-gate 		mpool_filter(t->bt_mp, __bt_pgin, __bt_pgout, t);
3147c478bd9Sstevel@tonic-gate 
3157c478bd9Sstevel@tonic-gate 	/* Create a root page if new tree. */
3167c478bd9Sstevel@tonic-gate 	if (nroot(t) == RET_ERROR)
3177c478bd9Sstevel@tonic-gate 		goto err;
3187c478bd9Sstevel@tonic-gate 
3197c478bd9Sstevel@tonic-gate 	/* Global flags. */
3207c478bd9Sstevel@tonic-gate 	if (dflags & DB_LOCK)
3217c478bd9Sstevel@tonic-gate 		F_SET(t, B_DB_LOCK);
3227c478bd9Sstevel@tonic-gate 	if (dflags & DB_SHMEM)
3237c478bd9Sstevel@tonic-gate 		F_SET(t, B_DB_SHMEM);
3247c478bd9Sstevel@tonic-gate 	if (dflags & DB_TXN)
3257c478bd9Sstevel@tonic-gate 		F_SET(t, B_DB_TXN);
3267c478bd9Sstevel@tonic-gate 
3277c478bd9Sstevel@tonic-gate 	return (dbp);
3287c478bd9Sstevel@tonic-gate 
3297c478bd9Sstevel@tonic-gate einval:	errno = EINVAL;
3307c478bd9Sstevel@tonic-gate 	goto err;
3317c478bd9Sstevel@tonic-gate 
3327c478bd9Sstevel@tonic-gate eftype:	errno = EFTYPE;
3337c478bd9Sstevel@tonic-gate 	goto err;
3347c478bd9Sstevel@tonic-gate 
3357c478bd9Sstevel@tonic-gate err:	if (t) {
3367c478bd9Sstevel@tonic-gate 		if (t->bt_dbp)
3377c478bd9Sstevel@tonic-gate 			free(t->bt_dbp);
3387c478bd9Sstevel@tonic-gate 		if (t->bt_fd != -1)
3397c478bd9Sstevel@tonic-gate 			(void)close(t->bt_fd);
3407c478bd9Sstevel@tonic-gate 		free(t);
3417c478bd9Sstevel@tonic-gate 	}
3427c478bd9Sstevel@tonic-gate 	return (NULL);
3437c478bd9Sstevel@tonic-gate }
3447c478bd9Sstevel@tonic-gate 
3457c478bd9Sstevel@tonic-gate /*
3467c478bd9Sstevel@tonic-gate  * NROOT -- Create the root of a new tree.
3477c478bd9Sstevel@tonic-gate  *
3487c478bd9Sstevel@tonic-gate  * Parameters:
3497c478bd9Sstevel@tonic-gate  *	t:	tree
3507c478bd9Sstevel@tonic-gate  *
3517c478bd9Sstevel@tonic-gate  * Returns:
3527c478bd9Sstevel@tonic-gate  *	RET_ERROR, RET_SUCCESS
3537c478bd9Sstevel@tonic-gate  */
3547c478bd9Sstevel@tonic-gate static int
nroot(t)3557c478bd9Sstevel@tonic-gate nroot(t)
3567c478bd9Sstevel@tonic-gate 	BTREE *t;
3577c478bd9Sstevel@tonic-gate {
3587c478bd9Sstevel@tonic-gate 	PAGE *meta, *root;
3597c478bd9Sstevel@tonic-gate 	db_pgno_t npg;
3607c478bd9Sstevel@tonic-gate 
3617c478bd9Sstevel@tonic-gate 	if ((root = mpool_get(t->bt_mp, 1, 0)) != NULL) {
3627c478bd9Sstevel@tonic-gate 		if (root->lower == 0 &&
3637c478bd9Sstevel@tonic-gate 		    root->pgno == 0 &&
3647c478bd9Sstevel@tonic-gate 		    root->linp[0] == 0) {
3657c478bd9Sstevel@tonic-gate 			mpool_delete(t->bt_mp, root);
3667c478bd9Sstevel@tonic-gate 			errno = EINVAL;
3677c478bd9Sstevel@tonic-gate 		} else {
3687c478bd9Sstevel@tonic-gate 			mpool_put(t->bt_mp, root, 0);
3697c478bd9Sstevel@tonic-gate 			return (RET_SUCCESS);
3707c478bd9Sstevel@tonic-gate 		}
3717c478bd9Sstevel@tonic-gate 	}
3727c478bd9Sstevel@tonic-gate 	if (errno != EINVAL)		/* It's OK to not exist. */
3737c478bd9Sstevel@tonic-gate 		return (RET_ERROR);
3747c478bd9Sstevel@tonic-gate 	errno = 0;
3757c478bd9Sstevel@tonic-gate 
3767c478bd9Sstevel@tonic-gate 	if ((meta = mpool_new(t->bt_mp, &npg, MPOOL_PAGE_NEXT)) == NULL)
3777c478bd9Sstevel@tonic-gate 		return (RET_ERROR);
3787c478bd9Sstevel@tonic-gate 
3797c478bd9Sstevel@tonic-gate 	if ((root = mpool_new(t->bt_mp, &npg, MPOOL_PAGE_NEXT)) == NULL)
3807c478bd9Sstevel@tonic-gate 		return (RET_ERROR);
3817c478bd9Sstevel@tonic-gate 
3827c478bd9Sstevel@tonic-gate 	if (npg != P_ROOT)
3837c478bd9Sstevel@tonic-gate 		return (RET_ERROR);
3847c478bd9Sstevel@tonic-gate 	root->pgno = npg;
3857c478bd9Sstevel@tonic-gate 	root->prevpg = root->nextpg = P_INVALID;
3867c478bd9Sstevel@tonic-gate 	root->lower = BTDATAOFF;
3877c478bd9Sstevel@tonic-gate 	root->upper = t->bt_psize;
3887c478bd9Sstevel@tonic-gate 	root->flags = P_BLEAF;
3897c478bd9Sstevel@tonic-gate 	memset(meta, 0, t->bt_psize);
3907c478bd9Sstevel@tonic-gate 	mpool_put(t->bt_mp, meta, MPOOL_DIRTY);
3917c478bd9Sstevel@tonic-gate 	mpool_put(t->bt_mp, root, MPOOL_DIRTY);
3927c478bd9Sstevel@tonic-gate 	return (RET_SUCCESS);
3937c478bd9Sstevel@tonic-gate }
3947c478bd9Sstevel@tonic-gate 
3957c478bd9Sstevel@tonic-gate static int
tmp()3967c478bd9Sstevel@tonic-gate tmp()
3977c478bd9Sstevel@tonic-gate {
3987c478bd9Sstevel@tonic-gate #ifdef SIG_BLOCK
3997c478bd9Sstevel@tonic-gate 	sigset_t set, oset;
4007c478bd9Sstevel@tonic-gate #else
4017c478bd9Sstevel@tonic-gate 	int oset;
4027c478bd9Sstevel@tonic-gate #endif
4037c478bd9Sstevel@tonic-gate 	int fd;
4047c478bd9Sstevel@tonic-gate 	char *envtmp;
4057c478bd9Sstevel@tonic-gate 	char path[MAXPATHLEN];
4067c478bd9Sstevel@tonic-gate 	static char fn[] = "/bt.XXXXXX";
4077c478bd9Sstevel@tonic-gate 
4087c478bd9Sstevel@tonic-gate 	envtmp = getenv("TMPDIR");
4097c478bd9Sstevel@tonic-gate 
4107c478bd9Sstevel@tonic-gate 	/* this used to be done with snprintf(), but since snprintf
4117c478bd9Sstevel@tonic-gate 	   isn't in most operating systems, and overflow checking in
4127c478bd9Sstevel@tonic-gate 	   this case is easy, this is what is done */
4137c478bd9Sstevel@tonic-gate 
4147c478bd9Sstevel@tonic-gate 	if (envtmp && ((strlen(envtmp)+sizeof(fn)+1) > sizeof(path)))
4157c478bd9Sstevel@tonic-gate 	    return(-1);
4167c478bd9Sstevel@tonic-gate 
4177c478bd9Sstevel@tonic-gate 	(void)sprintf(path, "%s%s", (envtmp ? envtmp : "/tmp"), fn);
4187c478bd9Sstevel@tonic-gate 
4197c478bd9Sstevel@tonic-gate #ifdef SIG_BLOCK
4207c478bd9Sstevel@tonic-gate 	(void)sigfillset(&set);
4217c478bd9Sstevel@tonic-gate 	(void)sigprocmask(SIG_BLOCK, &set, &oset);
4227c478bd9Sstevel@tonic-gate #else
4237c478bd9Sstevel@tonic-gate 	oset = sigblock(~0);
4247c478bd9Sstevel@tonic-gate #endif
4257c478bd9Sstevel@tonic-gate 	if ((fd = mkstemp(path)) != -1)
4267c478bd9Sstevel@tonic-gate 		(void)unlink(path);
4277c478bd9Sstevel@tonic-gate #ifdef SIG_BLOCK
4287c478bd9Sstevel@tonic-gate 	(void)sigprocmask(SIG_SETMASK, &oset, NULL);
4297c478bd9Sstevel@tonic-gate #else
4307c478bd9Sstevel@tonic-gate 	sigsetmask(oset);
4317c478bd9Sstevel@tonic-gate #endif
4327c478bd9Sstevel@tonic-gate #ifdef __CYGWIN32__
4337c478bd9Sstevel@tonic-gate       /* Ensure the fd is in binary mode. */
4347c478bd9Sstevel@tonic-gate       setmode(fd, O_BINARY);
4357c478bd9Sstevel@tonic-gate #endif /* __CYGWIN32__ */
4367c478bd9Sstevel@tonic-gate 
4377c478bd9Sstevel@tonic-gate 	return(fd);
4387c478bd9Sstevel@tonic-gate }
4397c478bd9Sstevel@tonic-gate 
4407c478bd9Sstevel@tonic-gate static int
byteorder()4417c478bd9Sstevel@tonic-gate byteorder()
4427c478bd9Sstevel@tonic-gate {
4437c478bd9Sstevel@tonic-gate 	u_int32_t x;
4447c478bd9Sstevel@tonic-gate 	u_char *p;
4457c478bd9Sstevel@tonic-gate 
4467c478bd9Sstevel@tonic-gate 	x = 0x01020304;
4477c478bd9Sstevel@tonic-gate 	p = (u_char *)&x;
4487c478bd9Sstevel@tonic-gate 	switch (*p) {
4497c478bd9Sstevel@tonic-gate 	case 1:
4507c478bd9Sstevel@tonic-gate 		return (DB_BIG_ENDIAN);
4517c478bd9Sstevel@tonic-gate 	case 4:
4527c478bd9Sstevel@tonic-gate 		return (DB_LITTLE_ENDIAN);
4537c478bd9Sstevel@tonic-gate 	default:
4547c478bd9Sstevel@tonic-gate 		return (0);
4557c478bd9Sstevel@tonic-gate 	}
4567c478bd9Sstevel@tonic-gate }
4577c478bd9Sstevel@tonic-gate 
4587c478bd9Sstevel@tonic-gate int
__bt_fd(dbp)4597c478bd9Sstevel@tonic-gate __bt_fd(dbp)
4607c478bd9Sstevel@tonic-gate         const DB *dbp;
4617c478bd9Sstevel@tonic-gate {
4627c478bd9Sstevel@tonic-gate 	BTREE *t;
4637c478bd9Sstevel@tonic-gate 
4647c478bd9Sstevel@tonic-gate 	t = dbp->internal;
4657c478bd9Sstevel@tonic-gate 
4667c478bd9Sstevel@tonic-gate 	/* Toss any page pinned across calls. */
4677c478bd9Sstevel@tonic-gate 	if (t->bt_pinned != NULL) {
4687c478bd9Sstevel@tonic-gate 		mpool_put(t->bt_mp, t->bt_pinned, 0);
4697c478bd9Sstevel@tonic-gate 		t->bt_pinned = NULL;
4707c478bd9Sstevel@tonic-gate 	}
4717c478bd9Sstevel@tonic-gate 
4727c478bd9Sstevel@tonic-gate 	/* In-memory database can't have a file descriptor. */
4737c478bd9Sstevel@tonic-gate 	if (F_ISSET(t, B_INMEM)) {
4747c478bd9Sstevel@tonic-gate 		errno = ENOENT;
4757c478bd9Sstevel@tonic-gate 		return (-1);
4767c478bd9Sstevel@tonic-gate 	}
4777c478bd9Sstevel@tonic-gate 	return (t->bt_fd);
4787c478bd9Sstevel@tonic-gate }
479