freebsd-nq/lib/libc/db/recno/rec_get.c
Pedro F. Giffuni 8a16b7a18f General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

294 lines
6.8 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1990, 1993, 1994
* The Regents of the University of California. All rights reserved.
*
* 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. 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_get.c 8.9 (Berkeley) 8/18/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <errno.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <db.h>
#include "recno.h"
/*
* __REC_GET -- Get a record from the btree.
*
* Parameters:
* dbp: pointer to access method
* key: key to find
* data: data to return
* flag: currently unused
*
* Returns:
* RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
*/
int
__rec_get(const DB *dbp, const DBT *key, DBT *data, u_int flags)
{
BTREE *t;
EPG *e;
recno_t nrec;
int status;
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;
}
/* Get currently doesn't take any flags, and keys of 0 are illegal. */
if (flags || (nrec = *(recno_t *)key->data) == 0) {
errno = EINVAL;
return (RET_ERROR);
}
/*
* If we haven't seen this record yet, try to find it in the
* original file.
*/
if (nrec > t->bt_nrecs) {
if (F_ISSET(t, R_EOF | R_INMEM))
return (RET_SPECIAL);
if ((status = t->bt_irec(t, nrec)) != RET_SUCCESS)
return (status);
}
--nrec;
if ((e = __rec_search(t, nrec, SEARCH)) == NULL)
return (RET_ERROR);
status = __rec_ret(t, e, 0, NULL, data);
if (F_ISSET(t, B_DB_LOCK))
mpool_put(t->bt_mp, e->page, 0);
else
t->bt_pinned = e->page;
return (status);
}
/*
* __REC_FPIPE -- Get fixed length records from a pipe.
*
* Parameters:
* t: tree
* cnt: records to read
*
* Returns:
* RET_ERROR, RET_SUCCESS
*/
int
__rec_fpipe(BTREE *t, recno_t top)
{
DBT data;
recno_t nrec;
size_t len;
int ch;
u_char *p;
if (t->bt_rdata.size < t->bt_reclen) {
t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen);
if (t->bt_rdata.data == NULL)
return (RET_ERROR);
t->bt_rdata.size = t->bt_reclen;
}
data.data = t->bt_rdata.data;
data.size = t->bt_reclen;
for (nrec = t->bt_nrecs; nrec < top;) {
len = t->bt_reclen;
for (p = t->bt_rdata.data;; *p++ = ch)
if ((ch = getc(t->bt_rfp)) == EOF || !--len) {
if (ch != EOF)
*p = ch;
if (len != 0)
memset(p, t->bt_bval, len);
if (__rec_iput(t,
nrec, &data, 0) != RET_SUCCESS)
return (RET_ERROR);
++nrec;
break;
}
if (ch == EOF)
break;
}
if (nrec < top) {
F_SET(t, R_EOF);
return (RET_SPECIAL);
}
return (RET_SUCCESS);
}
/*
* __REC_VPIPE -- Get variable length records from a pipe.
*
* Parameters:
* t: tree
* cnt: records to read
*
* Returns:
* RET_ERROR, RET_SUCCESS
*/
int
__rec_vpipe(BTREE *t, recno_t top)
{
DBT data;
recno_t nrec;
size_t len;
size_t sz;
int bval, ch;
u_char *p;
bval = t->bt_bval;
for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
for (p = t->bt_rdata.data,
sz = t->bt_rdata.size;; *p++ = ch, --sz) {
if ((ch = getc(t->bt_rfp)) == EOF || ch == bval) {
data.data = t->bt_rdata.data;
data.size = p - (u_char *)t->bt_rdata.data;
if (ch == EOF && data.size == 0)
break;
if (__rec_iput(t, nrec, &data, 0)
!= RET_SUCCESS)
return (RET_ERROR);
break;
}
if (sz == 0) {
len = p - (u_char *)t->bt_rdata.data;
t->bt_rdata.size += (sz = 256);
t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_rdata.size);
if (t->bt_rdata.data == NULL)
return (RET_ERROR);
p = (u_char *)t->bt_rdata.data + len;
}
}
if (ch == EOF)
break;
}
if (nrec < top) {
F_SET(t, R_EOF);
return (RET_SPECIAL);
}
return (RET_SUCCESS);
}
/*
* __REC_FMAP -- Get fixed length records from a file.
*
* Parameters:
* t: tree
* cnt: records to read
*
* Returns:
* RET_ERROR, RET_SUCCESS
*/
int
__rec_fmap(BTREE *t, recno_t top)
{
DBT data;
recno_t nrec;
u_char *sp, *ep, *p;
size_t len;
if (t->bt_rdata.size < t->bt_reclen) {
t->bt_rdata.data = reallocf(t->bt_rdata.data, t->bt_reclen);
if (t->bt_rdata.data == NULL)
return (RET_ERROR);
t->bt_rdata.size = t->bt_reclen;
}
data.data = t->bt_rdata.data;
data.size = t->bt_reclen;
sp = (u_char *)t->bt_cmap;
ep = (u_char *)t->bt_emap;
for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
if (sp >= ep) {
F_SET(t, R_EOF);
return (RET_SPECIAL);
}
len = t->bt_reclen;
for (p = t->bt_rdata.data;
sp < ep && len > 0; *p++ = *sp++, --len);
if (len != 0)
memset(p, t->bt_bval, len);
if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
return (RET_ERROR);
}
t->bt_cmap = (caddr_t)sp;
return (RET_SUCCESS);
}
/*
* __REC_VMAP -- Get variable length records from a file.
*
* Parameters:
* t: tree
* cnt: records to read
*
* Returns:
* RET_ERROR, RET_SUCCESS
*/
int
__rec_vmap(BTREE *t, recno_t top)
{
DBT data;
u_char *sp, *ep;
recno_t nrec;
int bval;
sp = (u_char *)t->bt_cmap;
ep = (u_char *)t->bt_emap;
bval = t->bt_bval;
for (nrec = t->bt_nrecs; nrec < top; ++nrec) {
if (sp >= ep) {
F_SET(t, R_EOF);
return (RET_SPECIAL);
}
for (data.data = sp; sp < ep && *sp != bval; ++sp);
data.size = sp - (u_char *)data.data;
if (__rec_iput(t, nrec, &data, 0) != RET_SUCCESS)
return (RET_ERROR);
++sp;
}
t->bt_cmap = (caddr_t)sp;
return (RET_SUCCESS);
}