/*
* Add the given pair to the page
*
* Returns:
* 0 ==> OK
* 1 ==> failure
*/
extern int
__addel(HTAB *hashp, BUFHEAD *bufp, const DBT *key, const DBT *val)
{
u_int16_t *bp, *sop;
int do_expand;
bp = (u_int16_t *)bufp->page;
do_expand = 0;
while (bp[0] && (bp[2] < REAL_KEY || bp[bp[0]] < REAL_KEY))
/* Exception case */
if (bp[2] == FULL_KEY_DATA && bp[0] == 2)
/* This is the last page of a big key/data pair
and we need to add another page */
break;
else if (bp[2] < REAL_KEY && bp[bp[0]] != OVFLPAGE) {
bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0);
if (!bufp)
return (-1);
bp = (u_int16_t *)bufp->page;
} else
/* Try to squeeze key on this page */
if (FREESPACE(bp) > PAIRSIZE(key, val)) {
squeeze_key(bp, key, val);
return (0);
} else {
bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0);
if (!bufp)
return (-1);
bp = (u_int16_t *)bufp->page;
}
if (PAIRFITS(bp, key, val))
putpair(bufp->page, key, val);
else {
do_expand = 1;
bufp = __add_ovflpage(hashp, bufp);
if (!bufp)
return (-1);
sop = (u_int16_t *)bufp->page;
if (PAIRFITS(sop, key, val))
putpair((char *)sop, key, val);
else
if (__big_insert(hashp, bufp, key, val))
return (-1);
}
bufp->flags |= BUF_MOD;
/*
* If the average number of keys per bucket exceeds the fill factor,
* expand the table.
*/
hashp->NKEYS++;
if (do_expand ||
(hashp->NKEYS / (hashp->MAX_BUCKET + 1) > hashp->FFACTOR))
return (__expand_table(hashp));
return (0);
}
/*
* Called when we encounter an overflow or big key/data page during split
* handling. This is special cased since we have to begin checking whether
* the key/data pairs fit on their respective pages and because we may need
* overflow pages for both the old and new pages.
*
* The first page might be a page with regular key/data pairs in which case
* we have a regular overflow condition and just need to go on to the next
* page or it might be a big key/data pair in which case we need to fix the
* big key/data pair.
*
* Returns:
* 0 ==> success
* -1 ==> failure
*/
static int
ugly_split(
HTAB *hashp,
uint32_t obucket, /* Same as __split_page. */
BUFHEAD *old_bufp,
BUFHEAD *new_bufp,
int copyto, /* First byte on page which contains key/data values. */
int moved /* Number of pairs moved to new page. */
)
{
BUFHEAD *bufp; /* Buffer header for ino */
uint16_t *ino; /* Page keys come off of */
uint16_t *np; /* New page */
uint16_t *op; /* Page keys go on to if they aren't moving */
size_t temp;
BUFHEAD *last_bfp; /* Last buf header OVFL needing to be freed */
DBT key, val;
SPLIT_RETURN ret;
uint16_t n, off, ov_addr, scopyto;
char *cino; /* Character value of ino */
bufp = old_bufp;
ino = (uint16_t *)(void *)old_bufp->page;
np = (uint16_t *)(void *)new_bufp->page;
op = (uint16_t *)(void *)old_bufp->page;
last_bfp = NULL;
scopyto = (uint16_t)copyto; /* ANSI */
n = ino[0] - 1;
while (n < ino[0]) {
if (ino[2] < REAL_KEY && ino[2] != OVFLPAGE) {
if (__big_split(hashp, old_bufp,
new_bufp, bufp, (int)bufp->addr, obucket, &ret))
return (-1);
old_bufp = ret.oldp;
if (!old_bufp)
return (-1);
op = (uint16_t *)(void *)old_bufp->page;
new_bufp = ret.newp;
if (!new_bufp)
return (-1);
np = (uint16_t *)(void *)new_bufp->page;
bufp = ret.nextp;
if (!bufp)
return (0);
cino = (char *)bufp->page;
ino = (uint16_t *)(void *)cino;
last_bfp = ret.nextp;
} else if (ino[n + 1] == OVFLPAGE) {
ov_addr = ino[n];
/*
* Fix up the old page -- the extra 2 are the fields
* which contained the overflow information.
*/
ino[0] -= (moved + 2);
temp = sizeof(uint16_t) * (ino[0] + 3);
_DIAGASSERT(scopyto >= temp);
FREESPACE(ino) = (uint16_t)(scopyto - temp);
OFFSET(ino) = scopyto;
bufp = __get_buf(hashp, (uint32_t)ov_addr, bufp, 0);
if (!bufp)
return (-1);
ino = (uint16_t *)(void *)bufp->page;
n = 1;
scopyto = hashp->BSIZE;
moved = 0;
if (last_bfp)
__free_ovflpage(hashp, last_bfp);
last_bfp = bufp;
}
/* Move regular sized pairs of there are any */
off = hashp->BSIZE;
for (n = 1; (n < ino[0]) && (ino[n + 1] >= REAL_KEY); n += 2) {
cino = (char *)(void *)ino;
key.data = (uint8_t *)cino + ino[n];
key.size = off - ino[n];
val.data = (uint8_t *)cino + ino[n + 1];
val.size = ino[n] - ino[n + 1];
off = ino[n + 1];
if (__call_hash(hashp, key.data, (int)key.size) == obucket) {
/* Keep on old page */
if (PAIRFITS(op, (&key), (&val)))
putpair((char *)(void *)op, &key, &val);
else {
old_bufp =
__add_ovflpage(hashp, old_bufp);
if (!old_bufp)
return (-1);
op = (uint16_t *)(void *)old_bufp->page;
putpair((char *)(void *)op, &key, &val);
}
old_bufp->flags |= BUF_MOD;
} else {
/* Move to new page */
if (PAIRFITS(np, (&key), (&val)))
putpair((char *)(void *)np, &key, &val);
else {
new_bufp =
__add_ovflpage(hashp, new_bufp);
if (!new_bufp)
return (-1);
np = (uint16_t *)(void *)new_bufp->page;
putpair((char *)(void *)np, &key, &val);
}
new_bufp->flags |= BUF_MOD;
}
}
}
if (last_bfp)
__free_ovflpage(hashp, last_bfp);
return (0);
}
static int
ugly_split(HTAB *hashp, uint32 obucket, BUFHEAD *old_bufp,
BUFHEAD *new_bufp, /* Same as __split_page. */ int copyto, int moved)
/* int copyto; First byte on page which contains key/data values. */
/* int moved; Number of pairs moved to new page. */
{
register BUFHEAD *bufp; /* Buffer header for ino */
register uint16 *ino; /* Page keys come off of */
register uint16 *np; /* New page */
register uint16 *op; /* Page keys go on to if they aren't moving */
uint32 loop_detection = 0;
BUFHEAD *last_bfp; /* Last buf header OVFL needing to be freed */
DBT key, val;
SPLIT_RETURN ret;
uint16 n, off, ov_addr, scopyto;
char *cino; /* Character value of ino */
int status;
bufp = old_bufp;
ino = (uint16 *)old_bufp->page;
np = (uint16 *)new_bufp->page;
op = (uint16 *)old_bufp->page;
last_bfp = NULL;
scopyto = (uint16)copyto; /* ANSI */
n = ino[0] - 1;
while (n < ino[0]) {
/* this function goes nuts sometimes and never returns.
* I havent found the problem yet but I need a solution
* so if we loop too often we assume a database curruption error
* :LJM
*/
loop_detection++;
if (loop_detection > MAX_UGLY_SPLIT_LOOPS)
return DATABASE_CORRUPTED_ERROR;
if (ino[2] < REAL_KEY && ino[2] != OVFLPAGE) {
if ((status = __big_split(hashp, old_bufp,
new_bufp, bufp, bufp->addr, obucket, &ret)))
return (status);
old_bufp = ret.oldp;
if (!old_bufp)
return (-1);
op = (uint16 *)old_bufp->page;
new_bufp = ret.newp;
if (!new_bufp)
return (-1);
np = (uint16 *)new_bufp->page;
bufp = ret.nextp;
if (!bufp)
return (0);
cino = (char *)bufp->page;
ino = (uint16 *)cino;
last_bfp = ret.nextp;
} else if (ino[n + 1] == OVFLPAGE) {
ov_addr = ino[n];
/*
* Fix up the old page -- the extra 2 are the fields
* which contained the overflow information.
*/
ino[0] -= (moved + 2);
FREESPACE(ino) =
scopyto - sizeof(uint16) * (ino[0] + 3);
OFFSET(ino) = scopyto;
bufp = __get_buf(hashp, ov_addr, bufp, 0);
if (!bufp)
return (-1);
ino = (uint16 *)bufp->page;
n = 1;
scopyto = hashp->BSIZE;
moved = 0;
if (last_bfp)
__free_ovflpage(hashp, last_bfp);
last_bfp = bufp;
}
/* Move regular sized pairs of there are any */
off = hashp->BSIZE;
for (n = 1; (n < ino[0]) && (ino[n + 1] >= REAL_KEY); n += 2) {
cino = (char *)ino;
key.data = (uint8 *)cino + ino[n];
key.size = off - ino[n];
val.data = (uint8 *)cino + ino[n + 1];
val.size = ino[n] - ino[n + 1];
off = ino[n + 1];
if (__call_hash(hashp, (char *)key.data, key.size) == obucket) {
/* Keep on old page */
if (PAIRFITS(op, (&key), (&val)))
putpair((char *)op, &key, &val);
else {
old_bufp =
__add_ovflpage(hashp, old_bufp);
if (!old_bufp)
return (-1);
op = (uint16 *)old_bufp->page;
putpair((char *)op, &key, &val);
}
old_bufp->flags |= BUF_MOD;
} else {
/* Move to new page */
if (PAIRFITS(np, (&key), (&val)))
putpair((char *)np, &key, &val);
else {
new_bufp =
__add_ovflpage(hashp, new_bufp);
if (!new_bufp)
return (-1);
np = (uint16 *)new_bufp->page;
putpair((char *)np, &key, &val);
}
new_bufp->flags |= BUF_MOD;
}
}
}
if (last_bfp)
__free_ovflpage(hashp, last_bfp);
return (0);
}
/*
* Add the given pair to the page
*
* Returns:
* 0 ==> OK
* 1 ==> failure
*/
extern int
__addel(HTAB *hashp, BUFHEAD *bufp, const DBT *key, const DBT *val)
{
register uint16 *bp, *sop;
int do_expand;
bp = (uint16 *)bufp->page;
do_expand = 0;
while (bp[0] && (bp[2] < REAL_KEY || bp[bp[0]] < REAL_KEY))
/* Exception case */
if (bp[2] == FULL_KEY_DATA && bp[0] == 2)
/* This is the last page of a big key/data pair
and we need to add another page */
break;
else if (bp[2] < REAL_KEY && bp[bp[0]] != OVFLPAGE) {
bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0);
if (!bufp) {
#ifdef DEBUG
assert(0);
#endif
return (-1);
}
bp = (uint16 *)bufp->page;
} else
/* Try to squeeze key on this page */
if (FREESPACE(bp) > PAIRSIZE(key, val)) {
{
squeeze_key(bp, key, val);
/* LJM: I added this because I think it was
* left out on accident.
* if this isn't incremented nkeys will not
* be the actual number of keys in the db.
*/
hashp->NKEYS++;
return (0);
}
} else {
bufp = __get_buf(hashp, bp[bp[0] - 1], bufp, 0);
if (!bufp) {
#ifdef DEBUG
assert(0);
#endif
return (-1);
}
bp = (uint16 *)bufp->page;
}
if (PAIRFITS(bp, key, val))
putpair(bufp->page, key, (DBT *)val);
else {
do_expand = 1;
bufp = __add_ovflpage(hashp, bufp);
if (!bufp) {
#ifdef DEBUG
assert(0);
#endif
return (-1);
}
sop = (uint16 *)bufp->page;
if (PAIRFITS(sop, key, val))
putpair((char *)sop, key, (DBT *)val);
else if (__big_insert(hashp, bufp, key, val)) {
#ifdef DEBUG
assert(0);
#endif
return (-1);
}
}
bufp->flags |= BUF_MOD;
/*
* If the average number of keys per bucket exceeds the fill factor,
* expand the table.
*/
hashp->NKEYS++;
if (do_expand ||
(hashp->NKEYS / (hashp->MAX_BUCKET + 1) > hashp->FFACTOR))
return (__expand_table(hashp));
return (0);
}
/*
* Returns:
* 0 ==> OK
* -1 ==> Error
*/
extern int
__split_page(HTAB *hashp, uint32 obucket, uint32 nbucket)
{
register BUFHEAD *new_bufp, *old_bufp;
register uint16 *ino;
register uint16 *tmp_uint16_array;
register char *np;
DBT key, val;
uint16 n, ndx;
int retval;
uint16 copyto, diff, moved;
size_t off;
char *op;
copyto = (uint16)hashp->BSIZE;
off = (uint16)hashp->BSIZE;
old_bufp = __get_buf(hashp, obucket, NULL, 0);
if (old_bufp == NULL)
return (-1);
new_bufp = __get_buf(hashp, nbucket, NULL, 0);
if (new_bufp == NULL)
return (-1);
old_bufp->flags |= (BUF_MOD | BUF_PIN);
new_bufp->flags |= (BUF_MOD | BUF_PIN);
ino = (uint16 *)(op = old_bufp->page);
np = new_bufp->page;
moved = 0;
for (n = 1, ndx = 1; n < ino[0]; n += 2) {
if (ino[n + 1] < REAL_KEY) {
retval = ugly_split(hashp, obucket, old_bufp, new_bufp,
(int)copyto, (int)moved);
old_bufp->flags &= ~BUF_PIN;
new_bufp->flags &= ~BUF_PIN;
return (retval);
}
key.data = (uint8 *)op + ino[n];
/* check here for ino[n] being greater than
* off. If it is then the database has
* been corrupted.
*/
if (ino[n] > off)
return (DATABASE_CORRUPTED_ERROR);
key.size = off - ino[n];
#ifdef DEBUG
/* make sure the size is positive */
assert(((int)key.size) > -1);
#endif
if (__call_hash(hashp, (char *)key.data, key.size) == obucket) {
/* Don't switch page */
diff = copyto - off;
if (diff) {
copyto = ino[n + 1] + diff;
memmove(op + copyto, op + ino[n + 1],
off - ino[n + 1]);
ino[ndx] = copyto + ino[n] - ino[n + 1];
ino[ndx + 1] = copyto;
} else
copyto = ino[n + 1];
ndx += 2;
} else {
/* Switch page */
val.data = (uint8 *)op + ino[n + 1];
val.size = ino[n] - ino[n + 1];
/* if the pair doesn't fit something is horribly
* wrong. LJM
*/
tmp_uint16_array = (uint16 *)np;
if (!PAIRFITS(tmp_uint16_array, &key, &val))
return (DATABASE_CORRUPTED_ERROR);
putpair(np, &key, &val);
moved += 2;
}
off = ino[n + 1];
}
/* Now clean up the page */
ino[0] -= moved;
FREESPACE(ino) = copyto - sizeof(uint16) * (ino[0] + 3);
OFFSET(ino) = copyto;
#ifdef DEBUG3
(void)fprintf(stderr, "split %d/%d\n",
((uint16 *)np)[0] / 2,
((uint16 *)op)[0] / 2);
#endif
/* unpin both pages */
old_bufp->flags &= ~BUF_PIN;
new_bufp->flags &= ~BUF_PIN;
return (0);
}
