void BTree::WriteBlock (uchar *block, uint num)
{
- fseek (fp, num*header.block_size + sizeof (BTreeFileHeader), SEEK_SET);
+ num++;
+ fseek (fp, num*header.block_size, SEEK_SET);
fwrite (block, 1, header.block_size, fp);
}
return kout;
}
-void BTree::DelKey (const Clave &k) {}
+void BTree::DelKey (const Clave &k)
+{
+ std::string s = k;
+ std::cout << "========= Borrando " << s << " =================\n";
+ DelKeyR (new BTreeLeafData (k.Clone ()), 0, 0);
+}
+
+void BTree::DelKeyR (BTreeData *k, uint node_num, uint padre)
+{
+ std::list<BTreeData *> node_keys;
+ BTreeNodeHeader node_header;
+ uchar *node;
+
+ node = ReadBlock (node_num);
+ ReadNodoHeader (node, &node_header);
+ node_keys = ReadKeys (node, node_header);
+
+ std::list<BTreeData *>::iterator it = node_keys.begin ();
+ std::list<BTreeData *>::iterator ultima;
+ std::list<BTreeData *>::iterator posterior;
+
+ BTreeData *lchild;
+ if (node_header.level != 0) {
+ lchild = (*it++);
+ }
+ posterior = it;
+
+ while (it != node_keys.end ()) {
+ if ((*k) == (*(*it))) {
+ /* La encontre!, retorno */
+ if (node_header.level == 0) {
+ DelKeyFromLeaf (k->getClave (), node_num, padre);
+ } else {
+ uint left, right;
+ if (it == posterior) {
+ left = lchild->getChild ();
+ right = (*it)->getChild ();
+ } else {
+ left = (*ultima)->getChild ();
+ right = (*it)->getChild ();
+ }
+ std::cout << "Eliminar de Nodo con hijos : " << left << " y " << right << std::endl;
+ DelKeyFromNode (k->getClave (), node_num, padre, left, right);
+ }
+ return;
+ }
+
+ if ((*k) < (*(*it)))
+ break;
+ ultima = it;
+ it++;
+ }
+
+ /* Si llego aca y estoy en nivel 0 (una hoja) quiere
+ * decir que no lo encontre
+ */
+ if (node_header.level == 0) {
+ std::cout << "*** Clave no encontrada ***\n";
+ return;
+ }
+
+ /* TODO: Aca faltaria liberar memoria */
+ if (it == posterior) {
+ DelKeyR (k, lchild->getChild (), node_num);
+ } else {
+ DelKeyR (k, (*ultima)->getChild (), node_num);
+ }
+}
+
+void BTree::DelKeyFromLeaf (Clave *k, uint node_num, uint padre)
+{
+ BTreeData *data;
+ uchar *node;
+ BTreeNodeHeader node_header;
+ std::list<BTreeData *> node_keys;
+
+ node = ReadBlock (node_num);
+ ReadNodoHeader (node, &node_header);
+ node_keys = ReadKeys (node, node_header);
+
+ data = new BTreeLeafData (k);
+
+ std::list<BTreeData *>::iterator it;
+ it = node_keys.begin ();
+ while (it != node_keys.end ()) {
+ if ((*data) == (*(*it))) {
+ node_keys.erase (it);
+ break;
+ }
+ it++;
+ }
+
+ delete data;
+
+ /* TODO : que pasa cuando el nodo se queda vacio o con
+ * muy pocas claveS??
+ */
+ WriteKeys (node, node_header, node_keys);
+ WriteNodoHeader (node, &node_header);
+ WriteBlock (node, node_num);
+
+ /* Veo si se cumple la condición de minimalidad */
+ uint min_free = (header.block_size-sizeof(BTreeNodeHeader))/2;
+ if ((node_header.free_space > min_free) && (node_num != 0)) {
+ /* Oops! Debo pedir prestada clave */
+ uint hi, hd;
+ Clave *pedida;
+
+ FindBrothers (node_num, padre, hi, hd);
+
+ if ((pedida = GetKey (hi, 1)) != NULL) {
+ std::string s = *pedida;
+ std::cout << "Clave Pedida : " << s << std::endl;
+
+ pedida = ReplaceKeyInFather (node_num, padre, pedida);
+
+ node_keys.insert (node_keys.begin (), new BTreeLeafData (pedida));
+ } else if ((pedida = GetKey (hd, 0)) != NULL) {
+ std::string s = *pedida;
+ std::cout << "Clave Pedida : " << s << std::endl;
+
+ pedida = ReplaceKeyInFather (node_num, padre, pedida);
+
+ node_keys.push_back (new BTreeLeafData (pedida));
+ } else {
+ std::cout << "NADIE ME PUEDE PRESTAR, FUNDIR NODOS\n";
+ uint join1, join2;
+ if (hi != 0) {
+ std::cout << "Join con Hermano Izquierdo\n";
+ join1 = hi;
+ join2 = node_num;
+ } else {
+ std::cout << "Join con Hermano Derecho\n";
+ join1 = node_num;
+ join2 = hd;
+ }
+
+ JoinNodes (join1, join2, padre);
+ return;
+ }
+
+ WriteKeys (node, node_header, node_keys);
+ WriteNodoHeader (node, &node_header);
+ WriteBlock (node, node_num);
+ }
+
+ DeleteKeys (node_keys);
+ delete [] node;
+ std::cout << "Borrado de una hoja listo\n";
+}
+
+void BTree::JoinNodes (uint node1, uint node2, uint padre)
+{
+ uchar *n1, *n2, *npadre;
+ BTreeNodeHeader nh1, nh2, nhp;
+ std::list<BTreeData *> nk1, nk2, nkpadre;
+
+ /* Leo los nodos */
+ n1 = ReadBlock (node1);
+ n2 = ReadBlock (node2);
+ npadre = ReadBlock (padre);
+
+ ReadNodoHeader (n1, &nh1);
+ ReadNodoHeader (n2, &nh2);
+ ReadNodoHeader (npadre, &nhp);
+
+ /* Apunto de Unir */
+ uint tmp = header.block_size - sizeof (BTreeNodeHeader);
+ uint l = tmp - nh1.free_space;
+ l += tmp - nh1.free_space;
+ l += 4;
+
+ std::cout << "Espacio ocupado despues de unir : " << l << " de " << tmp << std::endl;
+
+ nk1 = ReadKeys (n1, nh1);
+ nk2 = ReadKeys (n2, nh2);
+ nkpadre = ReadKeys (npadre, nhp);
+
+ /* Busco la clave a juntar con los nodos */
+ std::list<BTreeData *>::iterator it = nkpadre.begin ();
+ std::list<BTreeData *>::iterator borrar_padre;
+ std::list<BTreeData *>::iterator sig;
+
+ Clave *cpadre;
+ BTreeData *lchild = (*it++);
+
+ if (lchild->getChild () == node1) {
+ cpadre = (*it)->getClave ();
+ //nkpadre.erase (it);
+ borrar_padre = it;
+ } else {
+ while (it != nkpadre.end ()) {
+ if ((*it)->getChild () == node1)
+ break;
+ it++;
+ }
+ cpadre = (*it)->getClave ();
+ //nkpadre.erase (it);
+ borrar_padre = it;
+ }
+ if (it == nkpadre.end ()) {
+ std::cout << "PANIC : Me pase sin encontrar la clave!!\n";
+ exit(1);
+ }
+ it++;
+ sig = it;
+
+ std::list<BTreeData *> newkeys;
+ std::list<BTreeData *>::iterator i;
+
+ i = nk1.begin ();
+ while (i != nk1.end ()) {
+ newkeys.push_back ( new BTreeLeafData ((*i)->getClave ()->Clone ()));
+ i++;
+ }
+ if (cpadre)
+ newkeys.push_back ( new BTreeLeafData (cpadre->Clone ()));
+ i = nk2.begin ();
+ while (i != nk2.end ()) {
+ newkeys.push_back ( new BTreeLeafData ((*i)->getClave ()->Clone ()));
+ i++;
+ }
+
+ std::cout << "Espacio ocupado por las nuevas claves : " << (newkeys.size()*4) << std::endl;
+ if ((newkeys.size()*4) > tmp) {
+ std::cout << "PANIC : El nodo fundido no entra !!!\n";
+ exit (1);
+ }
+
+/* if (padre == 0) {
+ nhp.level = 0;
+ WriteKeys (npadre, nhp, newkeys);
+ WriteNodoHeader (npadre, &nhp);
+ WriteBlock (npadre, padre);*/
+
+ /* TODO: Recuperar nodo1 y nodo2 */
+// } else {
+ WriteKeys (n1, nh1, newkeys);
+ WriteNodoHeader (n1, &nh1);
+ WriteBlock (n1, node1);
+
+ /* TODO : Recuperar node2 */
+ /* Actualizo punero al padre */
+ (*sig)->setChild (node1);
+
+ nkpadre.erase (borrar_padre);
+ WriteKeys (npadre, nhp, nkpadre);
+ WriteNodoHeader (npadre, &nhp);
+ WriteBlock (npadre, padre);
+ //}
+
+ DeleteKeys (nk1);
+ DeleteKeys (nk2);
+ DeleteKeys (nkpadre);
+ DeleteKeys (newkeys);
+
+ delete [] n1;
+ delete [] n2;
+ delete [] npadre;
+}
+
+Clave *BTree::GetKey (uint node_num, char maxmin)
+{
+ if (node_num == 0) {
+ std::cout << "Nodo no me puede prestar ... es NULL\n";
+ return NULL;
+ }
+
+ uchar *node;
+ BTreeNodeHeader node_header;
+ std::list<BTreeData *> node_keys;
+
+ node = ReadBlock (node_num);
+ ReadNodoHeader (node, &node_header);
+ node_keys = ReadKeys (node, node_header);
+
+ std::list<BTreeData *>::iterator it = node_keys.begin ();
+
+ if (node_header.level != 0) it++;
+
+ Clave *k;
+ uint free = node_header.free_space; // + (*it)->Size ();
+ uint min_free = (header.block_size - sizeof (BTreeNodeHeader))/2;
+ if (free > min_free) {
+ std::cout << "No puedo prestar : Free = " << free << " Minimo = " << min_free << std::endl;
+ PrintNode (node_num);
+ WriteKeys (node, node_header, node_keys);
+ WriteNodoHeader (node, &node_header);
+ WriteBlock (node, node_num);
+ DeleteKeys (node_keys);
+
+ delete [] node;
+
+ return NULL;
+ }
+
+ if (maxmin == 0) {
+ k = (*it)->getClave ()->Clone ();
+ node_keys.erase (it);
+ } else {
+ it = node_keys.end ();
+ it--;
+ k = (*it)->getClave ()->Clone ();
+ node_keys.erase (it);
+ }
+
+ WriteKeys (node, node_header, node_keys);
+ WriteNodoHeader (node, &node_header);
+ WriteBlock (node, node_num);
+ DeleteKeys (node_keys);
+
+ delete [] node;
+
+ return k;
+}
+
+void BTree::FindBrothers (uint node_num, uint padre, uint &left, uint &right)
+{
+ uchar *node;
+ BTreeNodeHeader node_header;
+ std::list<BTreeData *> node_keys;
+
+ node = ReadBlock (padre);
+ ReadNodoHeader (node, &node_header);
+ node_keys = ReadKeys (node, node_header);
+
+ std::list<BTreeData *>::iterator it = node_keys.begin ();
+ std::list<BTreeData *>::iterator anterior = node_keys.begin ();
+ std::list<BTreeData *>::iterator siguiente;
+
+ BTreeData *lchild = (*it++);
+
+ if (lchild->getChild () == node_num) {
+ /* Solo tengo hermano derecho */
+ std::cout << "Hermano Izquierdo : NO TENGO" << std::endl;
+ left = 0;
+ std::cout << "Hermano Derecho : " << (*it)->getChild () << std::endl;
+ right = (*it)->getChild ();
+ return;
+ }
+
+ while (it != node_keys.end ()) {
+ if ((*it)->getChild () == node_num)
+ break;
+ anterior = it;
+ it++;
+ }
+ siguiente = it++;
+
+ std::cout << "Hermano Izquierdo : " << (*anterior)->getChild () << std::endl;
+ left = (*anterior)->getChild ();
+ if (siguiente != node_keys.end ()) {
+ right = (*siguiente)->getChild ();
+ std::cout << "Hermano Derecho : " << (*siguiente)->getChild () << std::endl;
+ } else {
+ right = 0;
+ std::cout << "Hermano Derecho : NO TENGO" << std::endl;
+ }
+}
+
+Clave *BTree::ReplaceKeyInFather (uint node_num, uint padre, Clave *k)
+{
+ uchar *node;
+ BTreeNodeHeader node_header;
+ std::list<BTreeData *> node_keys;
+
+ node = ReadBlock (padre);
+ ReadNodoHeader (node, &node_header);
+ node_keys = ReadKeys (node, node_header);
+
+ std::list<BTreeData *>::iterator it = node_keys.begin ();
+ std::list<BTreeData *>::iterator anterior = node_keys.begin ();
+ std::list<BTreeData *>::iterator siguiente;
+
+ BTreeData *lchild = (*it++);
+
+ if (lchild->getChild () == node_num) {
+ Clave *ret = (*it)->getClave ();
+ (*it)->setClave (k);
+
+ WriteKeys (node, node_header, node_keys);
+ WriteNodoHeader (node, &node_header);
+ WriteBlock (node, padre);
+ DeleteKeys (node_keys);
+
+ delete [] node;
+ return ret;
+ }
+
+ while (it != node_keys.end ()) {
+ if ((*it)->getChild () == node_num)
+ break;
+ anterior = it;
+ it++;
+ }
+
+ Clave *ret = (*it)->getClave ();
+ (*it)->setClave (k);
+
+ WriteKeys (node, node_header, node_keys);
+ WriteNodoHeader (node, &node_header);
+ WriteBlock (node, padre);
+ DeleteKeys (node_keys);
+
+ delete [] node;
+ return ret;
+}
+
+void BTree::DelKeyFromNode (Clave *k, uint node_num, uint padre, uint left, uint right)
+{
+ uint padre_hijo;
+ uchar *node;
+ BTreeNodeHeader node_header;
+ std::list<BTreeData *> node_keys;
+
+ node = ReadBlock (padre);
+ ReadNodoHeader (node, &node_header);
+ node_keys = ReadKeys (node, node_header);
+
+ if (right != 0) {
+ std::cout << "Busco para la derecha y luego todo a la izquierda\n";
+ uchar *node_r;
+ BTreeNodeHeader node_hr;
+ std::list<BTreeData *> node_keyr;
+
+ /* Busco la clave inmediatamente superior en el arbol */
+ padre_hijo = node_num;
+ do {
+ node_r = ReadBlock (right);
+ ReadNodoHeader (node_r, &node_hr);
+ if (node_hr.level != 0) {
+ BTreeData *data_r;
+ node_keyr = ReadKeys (node_r, node_hr);
+ data_r = *(node_keyr.begin ());
+ padre_hijo = right;
+ right = data_r->getChild ();
+
+ DeleteKeys (node_keyr);
+ delete [] node_r;
+ }
+ } while (node_hr.level != 0);
+
+ std::cout << "Voy a reemplazar en el nodo " << right << std::endl;
+
+ /* Reemplazo la clave a borrar por la de la hoja */
+ node_keyr = ReadKeys (node_r, node_hr);
+ BTreeData *reemplazar = *(node_keyr.begin ());
+
+ std::string ss = *reemplazar;
+ std::cout << "Voy a reemplazar por : " << ss << std::endl;
+
+ BTreeData *data = new BTreeLeafData (k->Clone());
+
+ std::list<BTreeData *>::iterator it = node_keys.begin ();
+ while (it != node_keys.end ()) {
+ if ((*data) == (*(*it))) {
+ break;
+ }
+ it++;
+ }
+ if (it == node_keys.end ()) {
+ std::cout << "PANIC : No encontre la clave en el nodo!!!!\n";
+ std::string s = *data;
+ std::cout << s << std::endl;
+ PrintNode (node_num);
+ exit (1);
+ }
+ (*it)->setClave (reemplazar->getClave ());
+ reemplazar->setClave (k->Clone ());
+
+ std::cout << "Tengo todo reemplazado ...\n";
+
+ /* Grabo los nodos */
+ WriteKeys (node, node_header, node_keys);
+ WriteNodoHeader (node, &node_header);
+ WriteBlock (node, padre);
+ DeleteKeys (node_keys);
+ delete [] node;
+
+ WriteKeys (node_r, node_hr, node_keyr);
+ WriteNodoHeader (node_r, &node_hr);
+ WriteBlock (node_r, right);
+ DeleteKeys (node_keyr);
+ delete [] node_r;
+
+ std::cout << "Grabe todo en disco ...\n";
+
+ /* Ahora debo eliminar la clave que puse en el nodo hoja */
+ std::cout << "Borro la clave desde la hoja!\n";
+
+ DelKeyFromLeaf (k, right, padre_hijo);
+
+ std::cout << "Listo, Listo!\n";
+ } else if (left != 0) {
+ std::cout << "PANIC : Deberia poder reemplazar en la derecha!!!!!\n";
+ exit (1);
+ } else {
+ std::cout << "PANIC : No tengo hijos para reemplazar!!!!\n";
+ exit (1);
+ }
+}
void BTree::ReadNodoHeader (uchar *node, BTreeNodeHeader *header)
{
uchar *BTree::ReadBlock (uint num)
{
+ /* Como el bloque 0 se usa para el header, el Nodo "num"
+ * está en el bloque "num+1"
+ */
+ num++;
+
uchar *out = new uchar[header.block_size];
- fseek (fp, num*header.block_size + sizeof (BTreeFileHeader), SEEK_SET);
+ fseek (fp, num*header.block_size, SEEK_SET);
fread (out, 1, header.block_size, fp);
return out;
node_header.item_count = 0;
node_header.free_space = header.block_size - sizeof (BTreeNodeHeader);
+ uint acumulado = 0;
while (it != keys.end ()) {
BTreeData *d = (*it);
uchar *n = d->ToArray ();
+ acumulado += d->Size ();
+ //std::cout << "WriteKeys :: Acumulado = " << acumulado << std::endl;
memcpy (node, n, d->Size ());
delete [] n;
node += d->Size ();
fseek (fp, 0, SEEK_END);
filelen = ftell (fp);
- num = (filelen - sizeof (BTreeFileHeader))/header.block_size;
+ num = filelen/header.block_size - 1;
node = new uchar[header.block_size];
ReadNodoHeader (node, &nh);
return node;
}
-bool BTree::FindKey (const Clave &k)
+BTreeFindResult *BTree::FindKey (const Clave &k)
{
return FindKeyR (&k, 0);
}
-bool BTree::FindKeyR (const Clave *k, uint node_num)
+BTreeFindResult *BTree::FindKeyR (const Clave *k, uint node_num)
{
std::list<BTreeData *> node_keys;
BTreeNodeHeader node_header;
/* La encontre!, retorno */
delete [] node;
DeleteKeys (node_keys);
- return true;
+ BTreeFindResult *result = new BTreeFindResult ();
+ result->node = node_num;
+ result->header = node_header;
+ return result;
}
if ((*data) < (*(*it)))
it++;
}
}
-
projects / z.facultad / 75.52 / treemulator.git / blobdiff