/*
* 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);
}
/*
* Big_insert
*
* You need to do an insert and the key/data pair is too big
*
* Returns:
* 0 ==> OK
*-1 ==> ERROR
*/
int
__big_insert(HTAB *hashp, BUFHEAD *bufp, const DBT *key, const DBT *val)
{
uint16_t *p, n;
size_t key_size, val_size;
uint16_t space, move_bytes, off;
char *cp, *key_data, *val_data;
size_t temp;
cp = bufp->page; /* Character pointer of p. */
p = (uint16_t *)(void *)cp;
key_data = (char *)key->data;
_DBFIT(key->size, int);
key_size = key->size;
val_data = (char *)val->data;
_DBFIT(val->size, int);
val_size = val->size;
/* First move the Key */
temp = FREESPACE(p) - BIGOVERHEAD;
_DBFIT(temp, uint16_t);
space = (uint16_t)temp;
while (key_size) {
move_bytes = MIN(space, key_size);
off = OFFSET(p) - move_bytes;
memmove(cp + off, key_data, (size_t)move_bytes);
key_size -= move_bytes;
key_data += move_bytes;
n = p[0];
p[++n] = off;
p[0] = ++n;
temp = off - PAGE_META(n);
_DBFIT(temp, uint16_t);
FREESPACE(p) = (uint16_t)temp;
OFFSET(p) = off;
p[n] = PARTIAL_KEY;
bufp = __add_ovflpage(hashp, bufp);
if (!bufp)
return (-1);
n = p[0];
if (!key_size) {
space = FREESPACE(p);
if (space) {
move_bytes = MIN(space, val_size);
/*
* If the data would fit exactly in the
* remaining space, we must overflow it to the
* next page; otherwise the invariant that the
* data must end on a page with FREESPACE
* non-zero would fail.
*/
if (space == val_size && val_size == val->size)
goto toolarge;
off = OFFSET(p) - move_bytes;
memmove(cp + off, val_data, (size_t)move_bytes);
val_data += move_bytes;
val_size -= move_bytes;
p[n] = off;
p[n - 2] = FULL_KEY_DATA;
FREESPACE(p) = FREESPACE(p) - move_bytes;
OFFSET(p) = off;
} else {
toolarge:
p[n - 2] = FULL_KEY;
}
}
p = (uint16_t *)(void *)bufp->page;
cp = bufp->page;
bufp->flags |= BUF_MOD;
temp = FREESPACE(p) - BIGOVERHEAD;
_DBFIT(temp, uint16_t);
space = (uint16_t)temp;
}
/* Now move the data */
temp = FREESPACE(p) - BIGOVERHEAD;
_DBFIT(temp, uint16_t);
space = (uint16_t)temp;
while (val_size) {
move_bytes = MIN(space, val_size);
/*
* Here's the hack to make sure that if the data ends on the
* same page as the key ends, FREESPACE is at least one.
*/
if (space == val_size && val_size == val->size)
move_bytes--;
off = OFFSET(p) - move_bytes;
memmove(cp + off, val_data, (size_t)move_bytes);
val_size -= move_bytes;
val_data += move_bytes;
n = p[0];
p[++n] = off;
p[0] = ++n;
temp = off - PAGE_META(n);
_DBFIT(temp, uint16_t);
FREESPACE(p) = (uint16_t)temp;
OFFSET(p) = off;
if (val_size) {
p[n] = FULL_KEY;
bufp = __add_ovflpage(hashp, bufp);
if (!bufp)
return (-1);
cp = bufp->page;
p = (uint16_t *)(void *)cp;
} else
p[n] = FULL_KEY_DATA;
bufp->flags |= BUF_MOD;
temp = FREESPACE(p) - BIGOVERHEAD;
_DBFIT(temp, uint16_t);
space = (uint16_t)temp;
}
return (0);
}
/*
* Returns:
* 0 => OK
* -1 => error
*/
int
__big_split(
HTAB *hashp,
BUFHEAD *op, /* Pointer to where to put keys that go in old bucket */
BUFHEAD *np, /* Pointer to new bucket page */
/* Pointer to first page containing the big key/data */
BUFHEAD *big_keyp,
int addr, /* Address of big_keyp */
uint32_t obucket,/* Old Bucket */
SPLIT_RETURN *ret
)
{
BUFHEAD *tmpp;
uint16_t *tp;
BUFHEAD *bp;
DBT key, val;
uint32_t change;
uint16_t free_space, n, off;
size_t temp;
bp = big_keyp;
/* Now figure out where the big key/data goes */
if (__big_keydata(hashp, big_keyp, &key, &val, 0))
return (-1);
change = (__call_hash(hashp, key.data, (int)key.size) != obucket);
if ((ret->next_addr = __find_last_page(hashp, &big_keyp)) != 0) {
if (!(ret->nextp =
__get_buf(hashp, (uint32_t)ret->next_addr, big_keyp, 0)))
return (-1);
} else
ret->nextp = NULL;
/* Now make one of np/op point to the big key/data pair */
_DIAGASSERT(np->ovfl == NULL);
if (change)
tmpp = np;
else
tmpp = op;
tmpp->flags |= BUF_MOD;
#ifdef DEBUG1
(void)fprintf(stderr,
"BIG_SPLIT: %d->ovfl was %d is now %d\n", tmpp->addr,
(tmpp->ovfl ? tmpp->ovfl->addr : 0), (bp ? bp->addr : 0));
#endif
tmpp->ovfl = bp; /* one of op/np point to big_keyp */
tp = (uint16_t *)(void *)tmpp->page;
_DIAGASSERT(FREESPACE(tp) >= OVFLSIZE);
n = tp[0];
off = OFFSET(tp);
free_space = FREESPACE(tp);
tp[++n] = (uint16_t)addr;
tp[++n] = OVFLPAGE;
tp[0] = n;
OFFSET(tp) = off;
temp = free_space - OVFLSIZE;
_DBFIT(temp, uint16_t);
FREESPACE(tp) = (uint16_t)temp;
/*
* Finally, set the new and old return values. BIG_KEYP contains a
* pointer to the last page of the big key_data pair. Make sure that
* big_keyp has no following page (2 elements) or create an empty
* following page.
*/
ret->newp = np;
ret->oldp = op;
tp = (uint16_t *)(void *)big_keyp->page;
big_keyp->flags |= BUF_MOD;
if (tp[0] > 2) {
/*
* There may be either one or two offsets on this page. If
* there is one, then the overflow page is linked on normally
* and tp[4] is OVFLPAGE. If there are two, tp[4] contains
* the second offset and needs to get stuffed in after the
* next overflow page is added.
*/
n = tp[4];
free_space = FREESPACE(tp);
off = OFFSET(tp);
tp[0] -= 2;
temp = free_space + OVFLSIZE;
_DBFIT(temp, uint16_t);
FREESPACE(tp) = (uint16_t)temp;
OFFSET(tp) = off;
tmpp = __add_ovflpage(hashp, big_keyp);
if (!tmpp)
return (-1);
tp[4] = n;
} else
tmpp = big_keyp;
if (change)
ret->newp = tmpp;
else
ret->oldp = tmpp;
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);
}
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);
}
/*
* Big_insert
*
* You need to do an insert and the key/data pair is too big
*
* Returns:
* 0 ==> OK
*-1 ==> ERROR
*/
extern int
__big_insert(HTAB *hashp, BUFHEAD *bufp, const DBT *key, const DBT *val)
{
register uint16 *p;
uint key_size, n, val_size;
uint16 space, move_bytes, off;
char *cp, *key_data, *val_data;
cp = bufp->page; /* Character pointer of p. */
p = (uint16 *)cp;
key_data = (char *)key->data;
key_size = key->size;
val_data = (char *)val->data;
val_size = val->size;
/* First move the Key */
for (space = FREESPACE(p) - BIGOVERHEAD; key_size;
space = FREESPACE(p) - BIGOVERHEAD) {
move_bytes = PR_MIN(space, key_size);
off = OFFSET(p) - move_bytes;
memmove(cp + off, key_data, move_bytes);
key_size -= move_bytes;
key_data += move_bytes;
n = p[0];
p[++n] = off;
p[0] = ++n;
FREESPACE(p) = off - PAGE_META(n);
OFFSET(p) = off;
p[n] = PARTIAL_KEY;
bufp = __add_ovflpage(hashp, bufp);
if (!bufp)
return (-1);
n = p[0];
if (!key_size) {
if (FREESPACE(p)) {
move_bytes = PR_MIN(FREESPACE(p), val_size);
off = OFFSET(p) - move_bytes;
p[n] = off;
memmove(cp + off, val_data, move_bytes);
val_data += move_bytes;
val_size -= move_bytes;
p[n - 2] = FULL_KEY_DATA;
FREESPACE(p) = FREESPACE(p) - move_bytes;
OFFSET(p) = off;
}
else
p[n - 2] = FULL_KEY;
}
p = (uint16 *)bufp->page;
cp = bufp->page;
bufp->flags |= BUF_MOD;
}
/* Now move the data */
for (space = FREESPACE(p) - BIGOVERHEAD; val_size;
space = FREESPACE(p) - BIGOVERHEAD) {
move_bytes = PR_MIN(space, val_size);
/*
* Here's the hack to make sure that if the data ends on the
* same page as the key ends, FREESPACE is at least one.
*/
if (space == val_size && val_size == val->size)
move_bytes--;
off = OFFSET(p) - move_bytes;
memmove(cp + off, val_data, move_bytes);
val_size -= move_bytes;
val_data += move_bytes;
n = p[0];
p[++n] = off;
p[0] = ++n;
FREESPACE(p) = off - PAGE_META(n);
OFFSET(p) = off;
if (val_size) {
p[n] = FULL_KEY;
bufp = __add_ovflpage(hashp, bufp);
if (!bufp)
return (-1);
cp = bufp->page;
p = (uint16 *)cp;
}
else
p[n] = FULL_KEY_DATA;
bufp->flags |= BUF_MOD;
}
return (0);
}