4.4BSD/usr/src/contrib/nvi/nvi/PORT/db/recno/rec_open.c
/*-
* Copyright (c) 1990, 1993
* 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[] = "@(#)rec_open.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stddef.h>
#include <stdio.h>
#include <unistd.h>
#include <db.h>
#include "recno.h"
DB *
__rec_open(fname, flags, mode, openinfo)
const char *fname;
int flags, mode;
const RECNOINFO *openinfo;
{
BTREE *t;
BTREEINFO btopeninfo;
DB *dbp;
PAGE *h;
struct stat sb;
int rfd, sverrno;
/* Open the user's file -- if this fails, we're done. */
if (fname != NULL && (rfd = open(fname, flags, mode)) < 0)
return (NULL);
/* Create a btree in memory (backed by disk). */
dbp = NULL;
if (openinfo) {
if (openinfo->flags & ~(R_FIXEDLEN | R_NOKEY | R_SNAPSHOT))
goto einval;
btopeninfo.flags = 0;
btopeninfo.cachesize = openinfo->cachesize;
btopeninfo.maxkeypage = 0;
btopeninfo.minkeypage = 0;
btopeninfo.psize = openinfo->psize;
btopeninfo.compare = NULL;
btopeninfo.prefix = NULL;
btopeninfo.lorder = openinfo->lorder;
dbp = __bt_open(openinfo->bfname,
O_RDWR, S_IRUSR | S_IWUSR, &btopeninfo);
} else
dbp = __bt_open(NULL, O_RDWR, S_IRUSR | S_IWUSR, NULL);
if (dbp == NULL)
goto err;
/*
* Some fields in the tree structure are recno specific. Fill them
* in and make the btree structure look like a recno structure. We
* don't change the bt_ovflsize value, it's close enough and slightly
* bigger.
*/
t = dbp->internal;
if (openinfo) {
if (openinfo->flags & R_FIXEDLEN) {
SET(t, R_FIXLEN);
t->bt_reclen = openinfo->reclen;
if (t->bt_reclen == 0)
goto einval;
}
t->bt_bval = openinfo->bval;
} else
t->bt_bval = '\n';
SET(t, R_RECNO);
if (fname == NULL)
SET(t, R_EOF | R_INMEM);
else
t->bt_rfd = rfd;
t->bt_rcursor = 0;
/*
* In 4.4BSD stat(2) returns true for ISSOCK on pipes. Until
* then, this is fairly close. Pipes are read-only.
*/
if (fname != NULL) {
if (lseek(rfd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) {
switch (flags & O_ACCMODE) {
case O_RDONLY:
SET(t, R_RDONLY);
break;
default:
goto einval;
}
slow: if ((t->bt_rfp = fdopen(rfd, "r")) == NULL)
goto err;
SET(t, R_CLOSEFP);
t->bt_irec =
ISSET(t, R_FIXLEN) ? __rec_fpipe : __rec_vpipe;
} else {
switch (flags & O_ACCMODE) {
case O_RDONLY:
SET(t, R_RDONLY);
break;
case O_RDWR:
break;
default:
goto einval;
}
if (fstat(rfd, &sb))
goto err;
/*
* Kluge -- we'd like to test to see if the file is too
* big to mmap. Since, we don't know what size or type
* off_t's or size_t's are, what the largest unsigned
* integral type is, or what random insanity the local
* C compiler will perpetrate, doing the comparison in
* a portable way is flatly impossible. Hope that mmap
* fails if the file is too large.
*/
if (sb.st_size == 0)
SET(t, R_EOF);
else {
t->bt_msize = sb.st_size;
if ((t->bt_smap =
mmap(NULL, t->bt_msize, PROT_READ, 0, rfd,
(off_t)0)) == (caddr_t)-1)
goto slow;
t->bt_cmap = t->bt_smap;
t->bt_emap = t->bt_smap + sb.st_size;
t->bt_irec = ISSET(t, R_FIXLEN) ?
__rec_fmap : __rec_vmap;
SET(t, R_MEMMAPPED);
}
}
}
/* Use the recno routines. */
dbp->close = __rec_close;
dbp->del = __rec_delete;
dbp->fd = __rec_fd;
dbp->get = __rec_get;
dbp->put = __rec_put;
dbp->seq = __rec_seq;
dbp->sync = __rec_sync;
/* If the root page was created, reset the flags. */
if ((h = mpool_get(t->bt_mp, P_ROOT, 0)) == NULL)
goto err;
if ((h->flags & P_TYPE) == P_BLEAF) {
h->flags = h->flags & ~P_TYPE | P_RLEAF;
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
} else
mpool_put(t->bt_mp, h, 0);
if (openinfo && openinfo->flags & R_SNAPSHOT &&
!ISSET(t, R_EOF | R_INMEM) &&
t->bt_irec(t, MAX_REC_NUMBER) == RET_ERROR)
goto err;
return (dbp);
einval: errno = EINVAL;
err: sverrno = errno;
if (dbp != NULL)
(void)__bt_close(dbp);
if (fname != NULL)
(void)close(rfd);
errno = sverrno;
return (NULL);
}
int
__rec_fd(dbp)
const DB *dbp;
{
BTREE *t;
t = dbp->internal;
if (ISSET(t, R_INMEM)) {
errno = ENOENT;
return (-1);
}
return (t->bt_rfd);
}