diff options
Diffstat (limited to 'db/recno/rec_open.c')
| -rw-r--r-- | db/recno/rec_open.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/db/recno/rec_open.c b/db/recno/rec_open.c new file mode 100644 index 0000000000..51d8a3c260 --- /dev/null +++ b/db/recno/rec_open.c @@ -0,0 +1,241 @@ +/*- + * 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[] = "@(#)rec_open.c 8.10 (Berkeley) 9/1/94"; +#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, dflags) + const char *fname; + int flags, mode, dflags; + 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, dflags); + } else + dbp = __bt_open(NULL, O_RDWR, S_IRUSR | S_IWUSR, NULL, dflags); + 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) { + F_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'; + + F_SET(t, R_RECNO); + if (fname == NULL) + F_SET(t, R_EOF | R_INMEM); + else + t->bt_rfd = rfd; + + if (fname != NULL) { + /* + * In 4.4BSD, stat(2) returns true for ISSOCK on pipes. + * Unfortunately, that's not portable, so we use lseek + * and check the errno values. + */ + errno = 0; + if (lseek(rfd, (off_t)0, SEEK_CUR) == -1 && errno == ESPIPE) { + switch (flags & O_ACCMODE) { + case O_RDONLY: + F_SET(t, R_RDONLY); + break; + default: + goto einval; + } +slow: if ((t->bt_rfp = fdopen(rfd, "r")) == NULL) + goto err; + F_SET(t, R_CLOSEFP); + t->bt_irec = + F_ISSET(t, R_FIXLEN) ? __rec_fpipe : __rec_vpipe; + } else { + switch (flags & O_ACCMODE) { + case O_RDONLY: + F_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) + F_SET(t, R_EOF); + else { +#ifdef MMAP_NOT_AVAILABLE + /* + * XXX + * Mmap doesn't work correctly on many current + * systems. In particular, it can fail subtly, + * with cache coherency problems. Don't use it + * for now. + */ + t->bt_msize = sb.st_size; + if ((t->bt_smap = mmap(NULL, t->bt_msize, + PROT_READ, MAP_PRIVATE, 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 = F_ISSET(t, R_FIXLEN) ? + __rec_fmap : __rec_vmap; + F_SET(t, R_MEMMAPPED); +#else + goto slow; +#endif + } + } + } + + /* 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) { + F_CLR(h, P_TYPE); + F_SET(h, P_RLEAF); + mpool_put(t->bt_mp, h, MPOOL_DIRTY); + } else + mpool_put(t->bt_mp, h, 0); + + if (openinfo && openinfo->flags & R_SNAPSHOT && + !F_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; + + /* 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, R_INMEM)) { + errno = ENOENT; + return (-1); + } + return (t->bt_rfd); +} |