X-Git-Url: https://git.llucax.com/z.facultad/75.52/treemulator.git/blobdiff_plain/81763ef5215161bd08100ea98910ae6bb093aea6..a857f3426b101f330a2d7baef64b2ff1f1e39bac:/src/btree.cpp diff --git a/src/btree.cpp b/src/btree.cpp index 38873c6..1bbb755 100644 --- a/src/btree.cpp +++ b/src/btree.cpp @@ -6,7 +6,7 @@ BTree::BTree (const std::string &name, unsigned int block_size, bool create_new_ uchar *node; BTreeNodeHeader nh; - fp = fopen (name.c_str(), "wb"); + fp = fopen (name.c_str(), "wb+"); if (!fp) { /* TODO : mandar una exception ? */ return; @@ -50,13 +50,183 @@ void BTree::WriteBlock (uchar *block, uint num) void BTree::AddKey (const Clave &k) { - AddKeyR (&k, 0); + uint left, right; + Clave *kout = AddKeyR (&k, 0, left, right); + + if (kout) { + unsigned short level; + /* Debo dejar la raiz en el nodo 0, por lo que paso el nodo + * que esta usando el hijo izquierdo a un nuevo nodo */ + std::list node_keys; + BTreeNodeHeader node_header; + uchar *node = ReadBlock (left); + ReadNodoHeader (node, &node_header); + node_keys = ReadKeys (node, node_header); + level = node_header.level + 1; + + uchar *new_node = NewBlock (left); + delete [] new_node; /* No me interesa, voy a usar lo leio antes */ + + WriteKeys (node, node_header, node_keys); + WriteNodoHeader (node, &node_header); + WriteBlock (node, left); + delete [] node; + + /* Leo y actualizo la Raiz */ + node = ReadBlock (0); + ReadNodoHeader (node, &node_header); + node_keys = std::list(); + + node_keys.push_back (new BTreeChildData (left)); + node_keys.push_back (new BTreeData (kout, right)); + + node_header.level = level; + node_header.item_count = 1; + + WriteKeys (node, node_header, node_keys); + WriteNodoHeader (node, &node_header); + WriteBlock (node, 0); + PrintNode (0); + } +} + +Clave* BTree::AddKeyR (const Clave *k, uint node_num, uint &left_child, uint &right_child) +{ + uchar *node = ReadBlock (node_num); + BTreeNodeHeader node_header; + ReadNodoHeader (node, &node_header); + delete [] node; + + if (node_header.level == 0) + return AddKeyLeafR (k, node_num, left_child, right_child); + + return AddKeyOtherR (k, node_num, left_child, right_child); } -Clave* BTree::AddKeyR (const Clave *k, uint node_num) +Clave* BTree::AddKeyLeafR (const Clave *k, uint node_num, uint &left_child, uint &right_child) { Clave *kout = NULL; - std::list node_keys; + std::list node_keys; + + BTreeData *data = new BTreeLeafData (k->Clone ()); + + /* Leo el nodo raiz para empezar a agregar */ + uchar *node = ReadBlock (node_num); + BTreeNodeHeader node_header; + ReadNodoHeader (node, &node_header); + + if (node_header.free_space > data->Size ()) { + BTreeData *datait; + node_keys = ReadKeys (node, node_header); + std::list::iterator it = node_keys.begin (); + + while (it != node_keys.end ()) { + datait = (*it); + if ((*data) < (*datait)) + /* Me pase, lo agrego aca! */ + break; + it++; + } + node_keys.insert (it, data); + WriteKeys (node, node_header, node_keys); + WriteNodoHeader (node, &node_header); + WriteBlock (node, node_num); + + PrintNode (node_num); + } else { + /* Split : Creo e inicializo el nuevo nodo */ + std::list new_node_keys; + std::list old_node_keys; + BTreeNodeHeader new_node_header; + uint new_node_num; + uchar *new_node = NewBlock (new_node_num); + ReadNodoHeader (new_node, &new_node_header); + new_node_header.level = node_header.level; + + node_keys = ReadKeys (node, node_header); + new_node_keys = ReadKeys (new_node, new_node_header); + + /* Agrego la clave en la lista que ya tengo de manera ordenada */ + std::list::iterator it = node_keys.begin (); + std::list::iterator previt = node_keys.begin (); + + while (it != node_keys.end ()) { + BTreeData *datait; + datait = (*it); + if ((*data) < (*datait)) + /* Me pase, lo agrego aca! */ + break; + previt = it; + it++; + } + if (it != node_keys.end ()) + node_keys.insert (it, data); + else + node_keys.push_back (data); + + /* Tengo que guardar claves hasta ocupar nodo size/2 en cada nodo + * y subir la clave del medio */ + node_header.item_count = 0; + node_header.free_space = header.block_size - sizeof (BTreeNodeHeader); + + uint total_size = 0; + it = node_keys.begin (); + while (it != node_keys.end ()) { + BTreeData *datait; + datait = (*it); + total_size += datait->Size (); + it++; + /* Hack : Si me quedo con todas las claves, en el caso de ser + * del mismo tama#o se desbalancea. Hay que ver que efecto + * puede tener en el caso de claves de long. variable + */ + if (it == node_keys.end ()) + total_size -= datait->Size (); + } + + it = node_keys.begin (); + uint used = 0; + while (used < total_size/2) { + BTreeData *d = (*it); + old_node_keys.push_back (d); + used += d->Size (); + it++; + } + kout = (*it++)->getClave (); // Esta se retorna al "padre" para que se la agregue + + while (it != node_keys.end ()) { + BTreeData *d = (*it); + new_node_keys.push_back (d); + it++; + } + + /* Guardo */ + WriteKeys (node, node_header, old_node_keys); + WriteNodoHeader (node, &node_header); + WriteBlock (node, node_num); + WriteKeys (new_node, new_node_header, new_node_keys); + WriteNodoHeader (new_node, &new_node_header); + WriteBlock (new_node, new_node_num); + + PrintNode (node_num); + PrintNode (new_node_num); + + /* Paso los hijos */ + left_child = node_num; + right_child = new_node_num; + delete [] new_node; + delete [] node; + } + + return kout; +} + +Clave* BTree::AddKeyOtherR (const Clave *k, uint node_num, uint &left_child, uint &right_child) +{ + Clave *kout = NULL; + std::list node_keys; + + BTreeData *data = new BTreeLeafData (k->Clone ()); /* Leo el nodo raiz para empezar a agregar */ uchar *node = ReadBlock (node_num); @@ -64,24 +234,138 @@ Clave* BTree::AddKeyR (const Clave *k, uint node_num) ReadNodoHeader (node, &node_header); node_keys = ReadKeys (node, node_header); + + std::list::iterator it = node_keys.begin (); + std::list::iterator posterior; + std::list::iterator ultima; - if (node_header.free_space >= k->Size ()) { - /* TODO : Insertar ordenado */ - /* Siempre se agrega en una hoja */ - node_keys.push_back (BTreeLeafData (k->Clone ())); + /* Se supone que la primera es un hijo :) */ + BTreeData *lchild = (*it++); + posterior = it; + + while (it != node_keys.end ()) { + if ((*data) < (*(*it))) + break; + ultima = it; + it++; + } + + if (it == posterior) { + k = AddKeyR (k, lchild->getChild (), left_child, right_child); + } else { + k = AddKeyR (k, (*ultima)->getChild (), left_child, right_child); + } + /* Nada que hacer */ + if (!k) return NULL; + + data = new BTreeData (k->Clone (), right_child); + + if (node_header.free_space > data->Size ()) { + BTreeData *datait; + node_keys = ReadKeys (node, node_header); + std::list::iterator it = node_keys.begin (); + + while (it != node_keys.end ()) { + datait = (*it); + if ((*data) < (*datait)) + /* Me pase, lo agrego aca! */ + break; + it++; + } + node_keys.insert (it, data); WriteKeys (node, node_header, node_keys); WriteNodoHeader (node, &node_header); WriteBlock (node, node_num); - delete [] node; + + PrintNode (node_num); } else { - /* Split */ - /* Lo que debe pasar : - * 1) Separar N/2 claves en "nodo" - * 2) Separar N/2-1 claves en un nuevo nodo - * 3) kout = clave del medio y mandarla al padre - */ - std::cout << "SPLIT" << std::endl; + /* Split : Creo e inicializo el nuevo nodo */ + std::list new_node_keys; + std::list old_node_keys; + BTreeNodeHeader new_node_header; + uint new_node_num; + uchar *new_node = NewBlock (new_node_num); + ReadNodoHeader (new_node, &new_node_header); + new_node_header.level = node_header.level; + + node_keys = ReadKeys (node, node_header); + new_node_keys = ReadKeys (new_node, new_node_header); + + /* Agrego la clave en la lista que ya tengo de manera ordenada */ + std::list::iterator it = node_keys.begin (); + std::list::iterator previt = node_keys.begin (); + + previt = ++it; + + while (it != node_keys.end ()) { + BTreeData *datait; + datait = (*it); + if ((*data) < (*datait)) + /* Me pase, lo agrego aca! */ + break; + previt = it; + it++; + } + if (it != node_keys.end ()) + node_keys.insert (it, data); + else + node_keys.push_back (data); + + /* Tengo que guardar claves hasta ocupar nodo size/2 en cada nodo + * y subir la clave del medio */ + node_header.item_count = 0; + node_header.free_space = header.block_size - sizeof (BTreeNodeHeader); + + uint total_size = 0; + it = node_keys.begin (); + while (it != node_keys.end ()) { + BTreeData *datait; + datait = (*it); + total_size += datait->Size (); + it++; + /* Hack : Si me quedo con todas las claves, en el caso de ser + * del mismo tama#o se desbalancea. Hay que ver que efecto + * puede tener en el caso de claves de long. variable + */ + if (it == node_keys.end ()) + total_size -= datait->Size (); + } + + it = node_keys.begin (); + uint used = 0; + while (used < total_size/2) { + BTreeData *d = (*it); + old_node_keys.push_back (d); + used += d->Size (); + it++; + } + kout = (*it)->getClave (); // Esta se retorna al "padre" para que se la agregue + + new_node_keys.push_back ( new BTreeChildData ((*it)->getChild ())); + it++; + while (it != node_keys.end ()) { + BTreeData *d = (*it); + new_node_keys.push_back (d); + it++; + } + + /* Guardo */ + WriteKeys (node, node_header, old_node_keys); + WriteNodoHeader (node, &node_header); + WriteBlock (node, node_num); + WriteKeys (new_node, new_node_header, new_node_keys); + WriteNodoHeader (new_node, &new_node_header); + WriteBlock (new_node, new_node_num); + + PrintNode (node_num); + PrintNode (new_node_num); + + /* Paso los hijos */ + left_child = node_num; + right_child = new_node_num; + delete [] new_node; + delete [] node; } return kout; @@ -109,37 +393,104 @@ uchar *BTree::ReadBlock (uint num) return out; } -std::list BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_header) +std::list BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_header) { - std::list keys; + std::list keys; node += sizeof (BTreeNodeHeader); + uint count = node_header.item_count; - for (uint i=0; iSize (); + keys.push_back (d); + count--; + } + + for (uint i=0; iSize (); keys.push_back (data); } return keys; } -void BTree::WriteKeys (uchar *node, BTreeNodeHeader &node_header, std::list &keys) +void BTree::WriteKeys (uchar *node, BTreeNodeHeader &node_header, std::list &keys) { - std::list::iterator it = keys.begin (); + std::list::iterator it = keys.begin (); node += sizeof (BTreeNodeHeader); + node_header.item_count = 0; + node_header.free_space = header.block_size - sizeof (BTreeNodeHeader); + while (it != keys.end ()) { - BTreeData d = (*it); - memcpy (node, d.ToArray(), d.Size ()); - node += d.Size (); + BTreeData *d = (*it); + memcpy (node, d->ToArray(), d->Size ()); + node += d->Size (); + node_header.free_space -= d->Size (); + node_header.item_count++; it++; } /* TODO : incrementar node_header.item_count aca o fuera de este metodo? */ } + +void BTree::PrintNode (uint num) +{ + uchar *node = ReadBlock (num); + BTreeNodeHeader node_header; + ReadNodoHeader (node, &node_header); + + std::list node_keys = ReadKeys (node, node_header); + std::list::iterator it = node_keys.begin (); + + std::cout << "Nodo : " << num << std::endl; + std::cout << "Level : " << node_header.level << std::endl; + std::cout << "Items : " << node_header.item_count << std::endl; + std::cout << "Free : " << node_header.free_space << " (" << (header.block_size - sizeof (BTreeNodeHeader)) << ")" << std::endl; + while (it != node_keys.end ()) { + std::string s = *(*it); + std::cout << s << " "; + it++; + } + std::cout << std::endl; + + delete [] node; +} + +uchar *BTree::NewBlock (uint &num) +{ + long filelen; + uchar *node; + BTreeNodeHeader nh; + + fseek (fp, 0, SEEK_END); + filelen = ftell (fp); + + num = (filelen - sizeof (BTreeFileHeader))/header.block_size; + + node = new uchar[header.block_size]; + ReadNodoHeader (node, &nh); + nh.level = 0; + nh.free_space = header.block_size - sizeof (BTreeNodeHeader); + nh.item_count = 0; + WriteNodoHeader (node, &nh); + WriteBlock (node, num); + + return node; +} +