X-Git-Url: https://git.llucax.com/z.facultad/75.52/treemulator.git/blobdiff_plain/ee619d18f5d688c5ea2f630a80a3560de36a99ed..04db779a8aee626e80fb2d403cd22c7924babb44:/src/btree.cpp

diff --git a/src/btree.cpp b/src/btree.cpp
index a063bef..8747177 100644
--- a/src/btree.cpp
+++ b/src/btree.cpp
@@ -389,7 +389,549 @@ Clave* BTree::AddKeyOtherR (const Clave *k, uint node_num, uint &left_child, uin
 	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;
+			int tipoh;
+			if (hi != 0) {
+				std::cout << "Join con Hermano Izquierdo\n";
+				join1 = hi;
+				join2 = node_num;
+				tipoh = 0;
+			} else {
+				std::cout << "Join con Hermano Derecho\n";
+				join1 = node_num;
+				join2 = hd;
+				tipoh = 1;
+			}
+
+			JoinNodes (join1, join2, padre, tipoh);
+			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, int tipohermano)
+{
+	uchar *n1, *n2, *npadre;
+	BTreeNodeHeader nh1, nh2, nhp;
+	std::list<BTreeData *> nk1, nk2, nkpadre;
+
+	if (node1 == node2) {
+		std::cout << "PANIC : No puedo juntar el mismo nodo con si mismo!!\n";
+		exit (1);
+	}
+	if (node1 == padre) {
+		std::cout << "PANIC : No puedo juntar el mismo nodo con si mismo!!\n";
+		exit (1);
+	}
+	if (node2 == padre) {
+		std::cout << "PANIC : No puedo juntar el mismo nodo con si mismo!!\n";
+		exit (1);
+	}
+
+	PrintNode (padre);
+	PrintNode (node1);
+	PrintNode (node2);
+
+	/* 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 del padre a juntar con los nodos */
+	std::list<BTreeData *>::iterator it = nkpadre.begin ();
+	std::list<BTreeData *>::iterator borrar_padre;
+	std::list<BTreeData *>::iterator sig;
+	std::list<BTreeData *>::iterator anterior = it;
+	
+	Clave *cpadre;
+	BTreeData *lchild = (*it++);
+
+	if (lchild->getChild () == node1) {
+		cpadre = (*it)->getClave ();
+		borrar_padre = it;
+	} else {
+		while (it != nkpadre.end ()) {
+			if (tipohermano == 0) {
+				if ((*it)->getChild () == node2)
+					break;
+			} else {
+				if ((*it)->getChild () == node1)
+					break;
+			}
+			anterior = it;
+			it++;
+		}
+		cpadre = (*it)->getClave ();
+		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 (tipohermano == 0)
+		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);
+	}
+
+	/* Para el padre, tener 2 items significa tener solo 1 clave, ya que
+	 * el otro item es el LeftChild!
+	 */
+	if ((padre == 0) && (nhp.item_count == 2)) {
+		/* Si junte 2 nodos, cuyo padre era la raiz, y esta tenia
+		 * solo una clave, quiere decir que lo que me queda
+		 * es de nuevo solo una raiz con todas las claves
+		 */
+		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 */
+		(*anterior)->setChild (node1);
+	
+		nkpadre.erase (borrar_padre);
+		WriteKeys (npadre, nhp, nkpadre);
+		WriteNodoHeader (npadre, &nhp);
+		WriteBlock (npadre, padre);
+	}
+
+	std::cout << " ----- Luego de Fundir -----\n";
+	PrintNode (node1);
+	PrintNode (padre);
+	std::cout << " ---------------------------\n";
+
+	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 (node_num);
+	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 ()) {
+			std::string ss1, ss2;
+			ss1 = *data;
+			ss2 = *(*it);
+			std::cout << ss1 << " == " << ss2 << std::endl;
+			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, node_num);
+		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";
+		PrintNode (node_num);
+		PrintNode (right);
+		/* 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)
 {
@@ -448,11 +990,44 @@ std::list<BTreeData *> BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_heade
 		keys.push_back (data);
 	}
 
+	DeAbrevKey (keys);
 	return keys;
 }
 
+void BTree::AbrevKey (std::list<BTreeData *> &lst)
+{
+	/* Claves Fijas No se abrevian */
+	if (key_type == KEY_FIXED) return;
+
+	BTreeData *primera = NULL;
+	std::list<BTreeData *>::iterator it = lst.begin ();
+
+	while (it != lst.end ()) {
+		if ((*it)->Abrev (primera) == false)
+			primera = (*it);
+		it++;
+	}
+}
+
+void BTree::DeAbrevKey (std::list<BTreeData *> &lst)
+{
+	/* Claves Fijas No se abrevian */
+	if (key_type == KEY_FIXED) return;
+
+	BTreeData *primera = NULL;
+	std::list<BTreeData *>::iterator it = lst.begin ();
+
+	while (it != lst.end ()) {
+		if ((*it)->DesAbrev (primera) == false)
+			primera = (*it);
+		it++;
+	}
+}
+
 void BTree::WriteKeys (uchar *node, BTreeNodeHeader &node_header, std::list<BTreeData *> &keys)
 {
+	AbrevKey (keys);
+
 	std::list<BTreeData *>::iterator it = keys.begin ();
 
 	node += sizeof (BTreeNodeHeader);
@@ -460,9 +1035,12 @@ void BTree::WriteKeys (uchar *node, BTreeNodeHeader &node_header, std::list<BTre
 	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 ();
@@ -471,7 +1049,7 @@ void BTree::WriteKeys (uchar *node, BTreeNodeHeader &node_header, std::list<BTre
 		it++;
 	}
 
-	/* TODO : incrementar node_header.item_count aca o fuera de este metodo? */
+	DeAbrevKey (keys);
 }
 		
 void BTree::PrintNode (uint num)
@@ -520,12 +1098,12 @@ uchar *BTree::NewBlock (uint &num)
 	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;
@@ -557,7 +1135,10 @@ bool BTree::FindKeyR (const Clave *k, uint node_num)
 			/* 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)))
@@ -583,4 +1164,3 @@ void BTree::DeleteKeys (std::list<BTreeData *> &keys)
 		it++;
 	}
 }
-