Net2/usr/src/lib/libc/db/btree/utils.c
/*-
* Copyright (c) 1990 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[] = "@(#)utils.c 5.3 (Berkeley) 3/3/91";
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <db.h>
#include <stdlib.h>
#include <string.h>
#include "btree.h"
/*
* _BT_BUILDRET -- Build return key/data pair as a result of search or scan.
*
* This routine manages the statically allocated buffers in which we
* return data to the user.
*
* Parameters:
* t -- btree from which to return datum
* d -- DATUM to be returned to the user.
* data -- data argument supplied by user for return
* key -- key argument supplied by user for return
*
* Returns:
* RET_SUCCESS, RET_ERROR.
*
* Side Effects:
* May free and reallocate static buffers, if the data
* we want to return is bigger than the space we have to
* do so.
*/
int
_bt_buildret(t, d, data, key)
BTREE_P t;
DATUM *d;
DBT *data;
DBT *key;
{
static int _data_s = 0;
static int _key_s = 0;
static char *_data = (char *) NULL;
static char *_key = (char *) NULL;
pgno_t chain;
if (d->d_flags & D_BIGKEY) {
if (_key != (char *) NULL)
(void) free(_key);
(void) bcopy((char *) &(d->d_bytes[0]),
(char *) &chain,
sizeof(chain));
if (_bt_getbig(t, chain, &_key, &_key_s) == RET_ERROR)
return (RET_ERROR);
key->data = (u_char *)_key;
key->size = _key_s;
} else {
/* need more space for key? */
if (d->d_ksize > _key_s) {
if (_key != (char *) NULL)
(void) free (_key);
if ((_key = (char *) malloc((unsigned) d->d_ksize))
== (char *) NULL)
return (RET_ERROR);
_key_s = d->d_ksize;
}
key->data = (u_char *)_key;
if ((key->size = d->d_ksize) > 0)
(void) bcopy(&(d->d_bytes[0]),
_key,
(int) d->d_ksize);
}
if (d->d_flags & D_BIGDATA) {
if (_data != (char *) NULL)
(void) free(_data);
(void) bcopy(&(d->d_bytes[d->d_ksize]),
(char *) &chain,
sizeof(chain));
if (_bt_getbig(t, chain, &_data, &_data_s) == RET_ERROR)
return (RET_ERROR);
data->data = (u_char *)_data;
data->size = _data_s;
} else {
/* need more space for data? */
if (d->d_dsize > _data_s) {
if (_data != (char *) NULL)
(void) free (_data);
if ((_data = (char *) malloc((unsigned) d->d_dsize))
== (char *) NULL)
return (RET_ERROR);
_data_s = d->d_dsize;
}
data->data = (u_char *)_data;
if ((data->size = d->d_dsize) > 0)
(void) bcopy(&(d->d_bytes[d->d_ksize]),
_data,
(size_t) (d->d_dsize));
}
return (RET_SUCCESS);
}
/*
* _BT_CMP -- Compare a key to a given item on the current page.
*
* This routine is a wrapper for the user's comparison function.
*
* Parameters:
* t -- tree in which to do comparison
* p -- pointer to one argument for the comparison function
* n -- index of item to supply second arg to comparison function
*
* Returns:
* < 0 if p is < item at n
* = 0 if p is = item at n
* > 0 if p is > item at n
*/
int
_bt_cmp(t, p, n)
BTREE_P t;
char *p;
index_t n;
{
BTHEADER *h;
IDATUM *id;
DATUM *d;
char *arg;
int ignore;
int free_arg;
pgno_t chain;
int r;
h = t->bt_curpage;
/*
* The left-most key at any level of the tree on internal pages
* is guaranteed (artificially, by the code here) to be less than
* any user key. This saves us from having to update the leftmost
* key when the user inserts a new key in the tree smaller than
* anything we've seen yet.
*/
if (h->h_prevpg == P_NONE && !(h->h_flags & F_LEAF) && n == 0)
return (1);
if (h->h_flags & F_LEAF) {
d = (DATUM *) GETDATUM(h,n);
if (d->d_flags & D_BIGKEY) {
free_arg = TRUE;
bcopy(&(d->d_bytes[0]), (char *) &chain, sizeof(chain));
if (_bt_getbig(t, chain, &arg, &ignore) == RET_ERROR)
return (RET_ERROR);
} else {
free_arg = FALSE;
arg = &(d->d_bytes[0]);
}
} else {
id = (IDATUM *) GETDATUM(h,n);
if (id->i_flags & D_BIGKEY) {
free_arg = TRUE;
bcopy(&(id->i_bytes[0]),
(char *) &chain,
sizeof(chain));
if (_bt_getbig(t, chain, &arg, &ignore) == RET_ERROR)
return (RET_ERROR);
} else {
free_arg = FALSE;
arg = &(id->i_bytes[0]);
}
}
r = (*(t->bt_compare))(p, arg);
if (free_arg)
(void) free(arg);
return (r);
}
/*
* _BT_PUSH/_BT_POP -- Push/pop a parent page number on the parent stack.
*
* When we descend the tree, we keep track of parent pages in order
* to handle splits on insertions.
*
* Parameters:
* t -- tree for which to push parent
* pgno -- page number to push (_bt_push only)
*
* Returns:
* RET_SUCCESS, RET_ERROR.
*/
int
_bt_push(t, pgno)
BTREE_P t;
pgno_t pgno;
{
BTSTACK *new;
if ((new = (BTSTACK *) malloc((unsigned) sizeof(BTSTACK)))
== (BTSTACK *) NULL)
return (RET_ERROR);
new->bts_pgno = pgno;
new->bts_next = t->bt_stack;
t->bt_stack = new;
return (RET_SUCCESS);
}
pgno_t
_bt_pop(t)
BTREE_P t;
{
BTSTACK *s;
pgno_t p = P_NONE;
if ((s = t->bt_stack) != (BTSTACK *) NULL) {
p = s->bts_pgno;
t->bt_stack = s->bts_next;
(void) free ((char *) s);
}
return (p);
}
#ifdef DEBUG
void
_btdump(tree)
BTREE tree;
{
BTREE_P t = (BTREE_P) tree;
DATUM *d;
IDATUM *id;
BTHEADER *h;
pgno_t npages;
pgno_t i;
index_t cur, top;
npages = t->bt_npages;
(void) printf("\"%s\" fd %d pgsz %d curpg %d @ 0x%lx",
t->bt_fname, t->bt_s.bt_d.d_fd,
t->bt_psize, t->bt_curpage);
(void) printf("npg %d cmp 0x%lx flags=(", npages, t->bt_compare);
if (t->bt_flags & BTF_SEQINIT)
(void) printf("BTF_SEQINIT");
(void) printf(")\n");
for (i = P_ROOT; i <= npages; i++) {
if (_bt_getpage(t, i) == RET_ERROR)
_punt();
h = t->bt_curpage;
top = NEXTINDEX(h);
(void) printf(" page %d:\n", i);
(void) printf("\tpgno %d prev %d next %d\n",
h->h_pgno, h->h_prevpg, h->h_nextpg);
(void) printf("\tlower %d upper %d nextind %d flags (",
h->h_lower, h->h_upper, top);
if (h->h_flags & F_LEAF)
(void) printf("F_LEAF");
else
(void) printf("<internal>");
if (h->h_flags & F_DIRTY)
(void) printf("|F_DIRTY");
if (h->h_flags & F_PRESERVE)
(void) printf("|F_PRESERVE");
if (h->h_flags & F_CONT) {
(void) printf("|F_CONT)");
if (h->h_prevpg == P_NONE) {
size_t longsz;
(void) bcopy((char *) &(h->h_linp[0]),
(char *) &longsz,
sizeof(longsz));
printf("\n\t\t(chain start, data length %ld)",
longsz);
}
printf("\n");
continue;
}
(void) printf(")\n");
for (cur = 0; cur < top; cur++) {
(void) printf("\t [%d] off %d ", cur, h->h_linp[cur]);
if (h->h_flags & F_LEAF) {
d = (DATUM *) GETDATUM(h,cur);
(void) printf("ksize %d", d->d_ksize);
if (d->d_flags & D_BIGKEY)
(void) printf(" (indirect)");
(void) printf("; dsize %d", d->d_dsize);
if (d->d_flags & D_BIGDATA)
(void) printf(" (indirect)");
} else {
id = (IDATUM *) GETDATUM(h,cur);
(void) printf("size %d pgno %d",
id->i_size, id->i_pgno);
if (id->i_flags & D_BIGKEY)
(void) printf(" (indirect)");
}
(void) printf("\n");
}
(void) printf("\n");
}
}
#endif /* DEBUG */
#ifdef DEBUG
_punt()
{
int pid;
pid = getpid();
(void) kill(pid, SIGILL);
}
#endif /* DEBUG */