+++ /dev/null
-/*-
- * Copyright (c) 1990, 1993, 1994
- * The Regents of the University of California. All rights reserved.
- *
- * This code is derived from software contributed to Berkeley by
- * Mike Olson.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#if defined(LIBC_SCCS) && !defined(lint)
-static char sccsid[] = "@(#)bt_open.c 8.10 (Berkeley) 8/17/94";
-#endif /* LIBC_SCCS and not lint */
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/db/btree/bt_open.c,v 1.11 2002/03/22 21:52:01 obrien Exp $");
-
-/*
- * Implementation of btree access method for 4.4BSD.
- *
- * The design here was originally based on that of the btree access method
- * used in the Postgres database system at UC Berkeley. This implementation
- * is wholly independent of the Postgres code.
- */
-
-#include "namespace.h"
-#include <sys/param.h>
-#include <sys/stat.h>
-
-#include <errno.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include "un-namespace.h"
-
-#include <db.h>
-#include "btree.h"
-
-#ifdef DEBUG
-#undef MINPSIZE
-#define MINPSIZE 128
-#endif
-
-static int byteorder(void);
-static int nroot(BTREE *);
-static int tmp(void);
-
-/*
- * __BT_OPEN -- Open a btree.
- *
- * Creates and fills a DB struct, and calls the routine that actually
- * opens the btree.
- *
- * Parameters:
- * fname: filename (NULL for in-memory trees)
- * flags: open flag bits
- * mode: open permission bits
- * b: BTREEINFO pointer
- *
- * Returns:
- * NULL on failure, pointer to DB on success.
- *
- */
-DB *
-__bt_open(fname, flags, mode, openinfo, dflags)
- const char *fname;
- int flags, mode, dflags;
- const BTREEINFO *openinfo;
-{
- struct stat sb;
- BTMETA m;
- BTREE *t;
- BTREEINFO b;
- DB *dbp;
- pgno_t ncache;
- ssize_t nr;
- int machine_lorder;
-
- t = NULL;
-
- /*
- * Intention is to make sure all of the user's selections are okay
- * here and then use them without checking. Can't be complete, since
- * we don't know the right page size, lorder or flags until the backing
- * file is opened. Also, the file's page size can cause the cachesize
- * to change.
- */
- machine_lorder = byteorder();
- if (openinfo) {
- b = *openinfo;
-
- /* Flags: R_DUP. */
- if (b.flags & ~(R_DUP))
- goto einval;
-
- /*
- * Page size must be indx_t aligned and >= MINPSIZE. Default
- * page size is set farther on, based on the underlying file
- * transfer size.
- */
- if (b.psize &&
- (b.psize < MINPSIZE || b.psize > MAX_PAGE_OFFSET + 1 ||
- b.psize & (sizeof(indx_t) - 1) ))
- goto einval;
-
- /* Minimum number of keys per page; absolute minimum is 2. */
- if (b.minkeypage) {
- if (b.minkeypage < 2)
- goto einval;
- } else
- b.minkeypage = DEFMINKEYPAGE;
-
- /* If no comparison, use default comparison and prefix. */
- if (b.compare == NULL) {
- b.compare = __bt_defcmp;
- if (b.prefix == NULL)
- b.prefix = __bt_defpfx;
- }
-
- if (b.lorder == 0)
- b.lorder = machine_lorder;
- } else {
- b.compare = __bt_defcmp;
- b.cachesize = 0;
- b.flags = 0;
- b.lorder = machine_lorder;
- b.minkeypage = DEFMINKEYPAGE;
- b.prefix = __bt_defpfx;
- b.psize = 0;
- }
-
- /* Check for the ubiquitous PDP-11. */
- if (b.lorder != BIG_ENDIAN && b.lorder != LITTLE_ENDIAN)
- goto einval;
-
- /* Allocate and initialize DB and BTREE structures. */
- if ((t = (BTREE *)malloc(sizeof(BTREE))) == NULL)
- goto err;
- memset(t, 0, sizeof(BTREE));
- t->bt_fd = -1; /* Don't close unopened fd on error. */
- t->bt_lorder = b.lorder;
- t->bt_order = NOT;
- t->bt_cmp = b.compare;
- t->bt_pfx = b.prefix;
- t->bt_rfd = -1;
-
- if ((t->bt_dbp = dbp = (DB *)malloc(sizeof(DB))) == NULL)
- goto err;
- memset(t->bt_dbp, 0, sizeof(DB));
- if (t->bt_lorder != machine_lorder)
- F_SET(t, B_NEEDSWAP);
-
- dbp->type = DB_BTREE;
- dbp->internal = t;
- dbp->close = __bt_close;
- dbp->del = __bt_delete;
- dbp->fd = __bt_fd;
- dbp->get = __bt_get;
- dbp->put = __bt_put;
- dbp->seq = __bt_seq;
- dbp->sync = __bt_sync;
-
- /*
- * If no file name was supplied, this is an in-memory btree and we
- * open a backing temporary file. Otherwise, it's a disk-based tree.
- */
- if (fname) {
- switch (flags & O_ACCMODE) {
- case O_RDONLY:
- F_SET(t, B_RDONLY);
- break;
- case O_RDWR:
- break;
- case O_WRONLY:
- default:
- goto einval;
- }
-
- if ((t->bt_fd = _open(fname, flags, mode)) < 0)
- goto err;
-
- } else {
- if ((flags & O_ACCMODE) != O_RDWR)
- goto einval;
- if ((t->bt_fd = tmp()) == -1)
- goto err;
- F_SET(t, B_INMEM);
- }
-
- if (_fcntl(t->bt_fd, F_SETFD, 1) == -1)
- goto err;
-
- if (_fstat(t->bt_fd, &sb))
- goto err;
- if (sb.st_size) {
- if ((nr = _read(t->bt_fd, &m, sizeof(BTMETA))) < 0)
- goto err;
- if (nr != sizeof(BTMETA))
- goto eftype;
-
- /*
- * Read in the meta-data. This can change the notion of what
- * the lorder, page size and flags are, and, when the page size
- * changes, the cachesize value can change too. If the user
- * specified the wrong byte order for an existing database, we
- * don't bother to return an error, we just clear the NEEDSWAP
- * bit.
- */
- if (m.magic == BTREEMAGIC)
- F_CLR(t, B_NEEDSWAP);
- else {
- F_SET(t, B_NEEDSWAP);
- M_32_SWAP(m.magic);
- M_32_SWAP(m.version);
- M_32_SWAP(m.psize);
- M_32_SWAP(m.free);
- M_32_SWAP(m.nrecs);
- M_32_SWAP(m.flags);
- }
- if (m.magic != BTREEMAGIC || m.version != BTREEVERSION)
- goto eftype;
- if (m.psize < MINPSIZE || m.psize > MAX_PAGE_OFFSET + 1 ||
- m.psize & (sizeof(indx_t) - 1) )
- goto eftype;
- if (m.flags & ~SAVEMETA)
- goto eftype;
- b.psize = m.psize;
- F_SET(t, m.flags);
- t->bt_free = m.free;
- t->bt_nrecs = m.nrecs;
- } else {
- /*
- * Set the page size to the best value for I/O to this file.
- * Don't overflow the page offset type.
- */
- if (b.psize == 0) {
- b.psize = sb.st_blksize;
- if (b.psize < MINPSIZE)
- b.psize = MINPSIZE;
- if (b.psize > MAX_PAGE_OFFSET + 1)
- b.psize = MAX_PAGE_OFFSET + 1;
- }
-
- /* Set flag if duplicates permitted. */
- if (!(b.flags & R_DUP))
- F_SET(t, B_NODUPS);
-
- t->bt_free = P_INVALID;
- t->bt_nrecs = 0;
- F_SET(t, B_METADIRTY);
- }
-
- t->bt_psize = b.psize;
-
- /* Set the cache size; must be a multiple of the page size. */
- if (b.cachesize && b.cachesize & (b.psize - 1) )
- b.cachesize += (~b.cachesize & (b.psize - 1) ) + 1;
- if (b.cachesize < b.psize * MINCACHE)
- b.cachesize = b.psize * MINCACHE;
-
- /* Calculate number of pages to cache. */
- ncache = (b.cachesize + t->bt_psize - 1) / t->bt_psize;
-
- /*
- * The btree data structure requires that at least two keys can fit on
- * a page, but other than that there's no fixed requirement. The user
- * specified a minimum number per page, and we translated that into the
- * number of bytes a key/data pair can use before being placed on an
- * overflow page. This calculation includes the page header, the size
- * of the index referencing the leaf item and the size of the leaf item
- * structure. Also, don't let the user specify a minkeypage such that
- * a key/data pair won't fit even if both key and data are on overflow
- * pages.
- */
- t->bt_ovflsize = (t->bt_psize - BTDATAOFF) / b.minkeypage -
- (sizeof(indx_t) + NBLEAFDBT(0, 0));
- if (t->bt_ovflsize < NBLEAFDBT(NOVFLSIZE, NOVFLSIZE) + sizeof(indx_t))
- t->bt_ovflsize =
- NBLEAFDBT(NOVFLSIZE, NOVFLSIZE) + sizeof(indx_t);
-
- /* Initialize the buffer pool. */
- if ((t->bt_mp =
- mpool_open(NULL, t->bt_fd, t->bt_psize, ncache)) == NULL)
- goto err;
- if (!F_ISSET(t, B_INMEM))
- mpool_filter(t->bt_mp, __bt_pgin, __bt_pgout, t);
-
- /* Create a root page if new tree. */
- if (nroot(t) == RET_ERROR)
- goto err;
-
- /* Global flags. */
- if (dflags & DB_LOCK)
- F_SET(t, B_DB_LOCK);
- if (dflags & DB_SHMEM)
- F_SET(t, B_DB_SHMEM);
- if (dflags & DB_TXN)
- F_SET(t, B_DB_TXN);
-
- return (dbp);
-
-einval: errno = EINVAL;
- goto err;
-
-eftype: errno = EFTYPE;
- goto err;
-
-err: if (t) {
- if (t->bt_dbp)
- free(t->bt_dbp);
- if (t->bt_fd != -1)
- (void)_close(t->bt_fd);
- free(t);
- }
- return (NULL);
-}
-
-/*
- * NROOT -- Create the root of a new tree.
- *
- * Parameters:
- * t: tree
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS
- */
-static int
-nroot(t)
- BTREE *t;
-{
- PAGE *meta, *root;
- pgno_t npg;
-
- if ((meta = mpool_get(t->bt_mp, 0, 0)) != NULL) {
- mpool_put(t->bt_mp, meta, 0);
- return (RET_SUCCESS);
- }
- if (errno != EINVAL) /* It's OK to not exist. */
- return (RET_ERROR);
- errno = 0;
-
- if ((meta = mpool_new(t->bt_mp, &npg)) == NULL)
- return (RET_ERROR);
-
- if ((root = mpool_new(t->bt_mp, &npg)) == NULL)
- return (RET_ERROR);
-
- if (npg != P_ROOT)
- return (RET_ERROR);
- root->pgno = npg;
- root->prevpg = root->nextpg = P_INVALID;
- root->lower = BTDATAOFF;
- root->upper = t->bt_psize;
- root->flags = P_BLEAF;
- memset(meta, 0, t->bt_psize);
- mpool_put(t->bt_mp, meta, MPOOL_DIRTY);
- mpool_put(t->bt_mp, root, MPOOL_DIRTY);
- return (RET_SUCCESS);
-}
-
-static int
-tmp()
-{
- sigset_t set, oset;
- int fd;
- char *envtmp = NULL;
- char path[MAXPATHLEN];
-
- if (issetugid() == 0)
- envtmp = getenv("TMPDIR");
- (void)snprintf(path,
- sizeof(path), "%s/bt.XXXXXXXXXX", envtmp ? envtmp : "/tmp");
-
- (void)sigfillset(&set);
- (void)_sigprocmask(SIG_BLOCK, &set, &oset);
- if ((fd = mkstemp(path)) != -1)
- (void)unlink(path);
- (void)_sigprocmask(SIG_SETMASK, &oset, NULL);
- return(fd);
-}
-
-static int
-byteorder()
-{
- u_int32_t x;
- u_char *p;
-
- x = 0x01020304;
- p = (u_char *)&x;
- switch (*p) {
- case 1:
- return (BIG_ENDIAN);
- case 4:
- return (LITTLE_ENDIAN);
- default:
- return (0);
- }
-}
-
-int
-__bt_fd(dbp)
- const DB *dbp;
-{
- BTREE *t;
-
- t = dbp->internal;
-
- /* Toss any page pinned across calls. */
- if (t->bt_pinned != NULL) {
- mpool_put(t->bt_mp, t->bt_pinned, 0);
- t->bt_pinned = NULL;
- }
-
- /* In-memory database can't have a file descriptor. */
- if (F_ISSET(t, B_INMEM)) {
- errno = ENOENT;
- return (-1);
- }
- return (t->bt_fd);
-}
projects / apple / libc.git / blobdiff