/*
* --- UpdatePointer ------
*
* update an internal pointer (usually because a node merged)
*/
void
indexNode::updatePointer(void *keyInModNode, bSize_t keylen,
void *newSep, bSize_t sepLen) {
TOUCH();
//decide which pointer to modify
int targetPointer = locateKey(keyInModNode, keylen);
if ( (tree->comparisonFunction(keyInModNode,
keylen,
nth_key(targetPointer),
nth_keyLen(targetPointer))) )
targetPointer--;
nodeID_t *pointerCopy = new nodeID_t;
*pointerCopy = *(nodeID_t *)nth_value(targetPointer);
printf("MERGE insert: old sep = <%s, %ld>\n", (char *)nth_key(targetPointer), *(nodeID_t *)nth_value(targetPointer));
if (targetPointer >= 0) {
printf("insert: new sep = <%s, %ld>\n", (char *)newSep, *pointerCopy);
record *newSepRec = new record(newSep, sepLen, pointerCopy, sizeof(nodeID_t));
remove(nth_key(targetPointer), nth_keyLen(targetPointer));
insert(newSepRec, kNoDuplicates, wrap(&update_cb_insert));
} //else {
//do nothing
//}
return;
}
/*
* printRep
*
* output a string describing the node
*/
void
indexNode::printRep() {
FILE* debugFile;
char *debugFileName = getenv("BTREE_DEBUG");
if (debugFileName == NULL) {
return;
} else {
debugFile = fopen(debugFileName, "a");
}
fprintf(debugFile, "i ");
fprintf(debugFile, "%ld %d %ld ", ID, 0, header->p_zero);
for (int i = 0; i < header->numElems; i++) {
char key[512];
int len = nth_keyLen(i);
memcpy(key, (char *)nth_key(i), len);
key[len] = 0;
nodeID_t n = *(nodeID_t *)nth_value(i);
fprintf(debugFile, "%s %ld ", key, n);
}
fprintf(debugFile, "\n");
fflush(debugFile);
fclose(debugFile);
}
/*
* Remove -- remove an entry from this node
*
*
*/
void
indexNode::remove(void *key, bSize_t len) {
repOK();
TOUCH();
//find the index of the record corresponding to key
int i=0;
while ( (i < header->numElems) && (tree->comparisonFunction(key, len, nth_key(i),
nth_keyLen(i))) ) i++;
if (i == header->numElems) {
warn("attempt to delete non-existent element (indexNode)");
exit(1);
}
//shuffle the localPointers
for (int j = i; j < header->numElems - 1; j++)
header->localPointers[j] = header->localPointers[j+1];
header->numElems--;
repOK();
compact();
return;
}
void
indexNode::deleteChild(nodeID_t deletedID) {
int pos=0;
if (p_zero == deletedID) {
if (header->numElems == 0) p_zero = kEmptyNode;
else {
p_zero = *((nodeID_t *)nth_value(0));
remove(nth_key(0), nth_keyLen(0));
}
} else {
while ( (pos < header->numElems) && (*((nodeID_t *)nth_value(pos)) != deletedID) ) pos++;
if (pos == header->numElems) warn("error on deleteChild -- key not found");
remove(nth_key(pos), nth_keyLen(pos));
}
TOUCH();
return;
}
/*
* locateKey - determine where key is ordered with respect
* to the node's existing keys. Function returns
* the existing key that immediately follows key
*/
int indexNode::locateKey(void *key, int len) {
int i=0;
while ((i < header->numElems) && (tree->comparisonFunction(nth_key(i),
nth_keyLen(i),
key,
len) < 0)) i++;
return i;
}
/*
* Search - search called on an indexNode will return a nodeID_t. It will
* never return a value since store those only in the leaves
*
* This version uses a binary search
*/
nodeID_t indexNode::search(void *key, bSize_t len, void **retValue, bSize_t *retLen) {
/* int l, h,m, comp;
l=0; h = header->numElems - 1;
do {
m = (l + h) / 2;
void *cKey = nth_key(m);
bSize_t cLen = nth_keyLen(m);
comp = tree->comparisonFunction(key, len, cKey, cLen);
if (comp == 0) {
goto end;
} else if (comp < 0)
if (h==m) goto end; else h = m;
else
l = m+1;
} while (l <= h);
end:
//the search has hit one of the duplicate keys, return the associated pointer
if (comp == 0) return *(nodeID_t *)nth_value(m);
//the key isn't in the list, but return the right pointer
nodeID_t *p = NULL;
if (comp < 0)
if (m > 0)
p = (nodeID_t *)nth_value(m-1);
else
p = &p_zero;
else
p = (nodeID_t *)nth_value(m);
return *p;
*/
int i = 0;
int c = -1;
while ( (i < header->numElems) &&
((c = tree->comparisonFunction(key, len, nth_key(i), nth_keyLen(i))) > 0)) i++;
//hit dup
nodeID_t retVal=-666;
if (c == 0) retVal = *(nodeID_t *)nth_value(i);
//last pointer case
else if (i == header->numElems) retVal = *(nodeID_t *)nth_value(header->numElems - 1);
//p_zero case
else if (i == 0) retVal = p_zero;
else retVal = *(nodeID_t *)nth_value(i-1);
return retVal;
}
int seq_key(BTREE *bt, long page, int m, KEY *key, int *t)
{
PAGE_ADDRESS *p;
KEY *pk, *pkk;
long nx;
int l, r, k;
if (page == BTREE_NULL)
{
*t = m + 1;
return 0;
}
p = (PAGE_ADDRESS *) get_page(bt, page);
pk = (KEY *) (p + 1);
l = 0; r = p->nkeys-1;
do {
k = (l + r) / 2;
pkk = nth_key(bt, p, k);
if (bt->compare_key((void *) key, pkk) < 0) r = k - 1;
else
if (bt->compare_key((void *) key, pkk) > 0) l = k + 1;
else
break;
} while (r >= l);
if (r >= l)
{
m += p->child0+1;
for (r = 0; r < k; r++)
m += p->s[r].child + 1;
*t = m;
return 0; /* chave existe */
}
if (r < 0)
nx = p->next0;
else
{
nx = p->s[r].next;
m += p->child0 + 1;
for (k = 0; k < r; k++)
m += p->s[k].child + 1;
}
return seq_key(bt, nx, m, key, t);
}
int delete_key(BTREE *bt, long page, KEY *key)
{
PAGE_ADDRESS *p;
KEY *pk, *pkk;
long nx;
int l, r, k;
if (page == BTREE_NULL)
{
btree_errno = NON_KEY;
return -1;
}
p = (PAGE_ADDRESS *) get_page(bt, page);
pk = (KEY *) (p + 1);
l = 0; r = p->nkeys-1;
do {
k = (l + r) / 2;
pkk = nth_key(bt, p, k);
if (bt->compare_key((void *) key, pkk) < 0) r = k - 1;
else
if (bt->compare_key((void *) key, pkk) > 0) l = k + 1;
else
break;
} while (r >= l);
if (r >= l)
{
if (p->s[k].size < 0)
{
btree_errno = DEL_KEY;
return -1;
}
p->s[k].size *= -1;
return 0;
}
if (r < 0)
nx = p->next0;
else
nx = p->s[r].next;
return delete_key(bt, nx, key);
}
int search_key(BTREE *bt, long page, KEY *key, ITEM *u)
{
PAGE_ADDRESS *p;
KEY *pk, *pkk;
long nx;
int l, r, k;
if (page == BTREE_NULL)
{
u->next = page;
u->address = BTREE_NULL;
u->size = -1;
btree_errno = NON_KEY;
return -1;
}
p = (PAGE_ADDRESS *) get_page(bt, page);
pk = (KEY *) (p + 1);
l = 0; r = p->nkeys-1;
do {
k = (l + r) / 2;
pkk = nth_key(bt, p, k);
if (bt->compare_key((void *) key, pkk) < 0) r = k - 1;
else
if (bt->compare_key((void *) key, pkk) > 0) l = k + 1;
else
break;
} while (r >= l);
if (r >= l)
{
*u = p->s[k];
return 0; /* chave jah existe */
}
if (r < 0)
nx = p->next0;
else
nx = p->s[r].next;
return search_key(bt, nx, key, u);
}
int get_nth(BTREE *bt, long page, int n, KEY *key, ITEM *u)
{
PAGE_ADDRESS *p;
int i, cont;
if (page == BTREE_NULL)
{
btree_errno = INTERN_MIST;
return -1;
}
p = (PAGE_ADDRESS *) get_page(bt, page);
if (p->child0 >= n)
return get_nth(bt, p->next0, n, key, u);
n -= p->child0;
i = 0;
while (i < p->nkeys-1)
{
if (1 == n)
{
l1:
memcpy(key, nth_key(bt, p, i), bt->realkeysize);
*u = p->s[i];
return 0;
}
n--;
if (n <= p->s[i].child)
return get_nth(bt, p->s[i].next, n , key, u);
n-= p->s[i].child;
i++;
}
if (n == 1)
goto l1;
return get_nth(bt, p->s[i].next, n-1 , key, u);
}
int insert_key(BTREE *bt, long page, KEY *key, ITEM *u, KEY **hkey)
{
PAGE_ADDRESS *p, *b;
KEY *pk, *pkk, *vkey;
long nx;
int k, l, r, n;
ITEM v;
*hkey = NULL;
if (page == BTREE_NULL)
{
u->next = page;
u->child = 0;
*hkey = (KEY *) malloc(bt->keysize);
memcpy(*hkey, key, bt->realkeysize);
return 0;
}
p = (PAGE_ADDRESS *) get_page(bt, page);
pk = (KEY *) (p + 1);
l = 0; r = p->nkeys-1;
do {
k = (l + r) / 2;
pkk = nth_key(bt, p, k);
if (bt->compare_key((void *) key, pkk) < 0) r = k - 1;
else
if (bt->compare_key((void *) key, pkk) > 0) l = k + 1;
else
break;
} while (r >= l);
if (r >= l)
{
if (p->s[k].size < 0) /* chave foi deletada */
{
p->s[k].size = u->size;
p->s[k].address = u->address;
memcpy(nth_key(bt, p, k), key, bt->realkeysize);
return 0;
}
btree_errno = DUP_KEY;
return -1; /* chave jah existe */
}
if (r < 0)
nx = p->next0;
else
nx = p->s[r].next;
v = *u;
if ((k = insert_key(bt, nx, key, &v, &vkey)) < 0)
return k;
if (vkey == NULL)
{
if ( r < 0)
{
p->child0 += v.child;
}
else
{
p->s[r].child += v.child;
}
*u = v;
write_page(bt, p);
return 0;
}
p->s[r].child -= v.child;
if (p->nkeys < bt->order)
{
for (k = p->nkeys; k > r+1; k--)
{
p->s[k] = p->s[k-1];
pkk = nth_key(bt, p, k);
pk = nth_key(bt, p, k-1);
memcpy(pkk, pk, bt->realkeysize);
}
memcpy(nth_key(bt, p, k), vkey, bt->realkeysize);
p->s[k] = v;
p->nkeys++;
u->child = 1;
free(vkey);
write_page(bt, p);
return 0;
}
b = (PAGE_ADDRESS *) new_page(bt);
b->label = BTREE_LABEL;
n = bt->order / 2 - 1;
if (r <= n)
{
if (r != n)
{
*u = p->s[n];
*hkey = (KEY *) malloc(bt->keysize);
memcpy(*hkey, nth_key(bt, p, n), bt->realkeysize);
for (k = n ; k > r+1; k--)
{
p->s[k] = p->s[k-1];
pkk = nth_key(bt, p, k);
pk = nth_key(bt, p, k-1);
memcpy(pkk, pk, bt->realkeysize);
}
memcpy(nth_key(bt, p, k), vkey, bt->realkeysize);
p->s[k] = v;
free(vkey);
}
else
{
*u = v;
*hkey = vkey;
}
n++;
for (k = 0; k < n; k++)
{
b->s[k] = p->s[k+n];
memcpy(nth_key(bt, b, k), nth_key(bt, p, k+n), bt->realkeysize);
}
}
else
{
r = r - n - 1;
*u = p->s[n+1];
*hkey = (KEY *) malloc(bt->keysize);
memcpy(*hkey, nth_key(bt, p, n+1), bt->realkeysize);
for (k = 0; k < r; k++)
{
b->s[k] = p->s[k+n+2];
memcpy(nth_key(bt, b, k), nth_key(bt, p, k+n+2), bt->realkeysize);
}
memcpy(nth_key(bt, b, k), vkey, bt->realkeysize);
b->s[k] = v;
free(vkey);
n++;
for (k = r+1; k < n; k++)
{
b->s[k] = p->s[k+n];
memcpy(nth_key(bt, b, k), nth_key(bt, p, k+n), bt->realkeysize);
}
}
p->nkeys = b->nkeys = n;
b->next0 = u->next;
b->child0 = u->child;
u->next = address_of(bt, b);
u->child = n + b->child0;
for (k = 0; k < n; k++)
u->child += b->s[k].child;
write_page(bt, p);
write_page(bt, b);
return 0;
}