X-Git-Url: https://git.llucax.com/z.facultad/75.52/treemulator.git/blobdiff_plain/6fcd86dce909f05de818fdd78d76e70aabc3ad22..2c1d3ea3cf9a25e8f957587d4a1581fc292c831b:/src/btree.cpp diff --git a/src/btree.cpp b/src/btree.cpp index 1ad006d..cf01b2c 100644 --- a/src/btree.cpp +++ b/src/btree.cpp @@ -1,12 +1,12 @@ #include "btree.h" -BTree::BTree (const char *name, unsigned int block_size, bool create_new_file) +BTree::BTree (const std::string &name, unsigned int block_size, bool create_new_file) { uchar *node; + BTreeNodeHeader nh; - - fp = fopen (name, "wb"); + fp = fopen (name.c_str(), "wb"); if (!fp) { /* TODO : mandar una exception ? */ return; @@ -17,11 +17,17 @@ BTree::BTree (const char *name, unsigned int block_size, bool create_new_file) /* Inicializo el header */ header.block_size = block_size; - write_tree_header (); + WriteFileHeader (); /* Creo el primer bloque vacio */ node = new uchar[block_size]; - write_block (node, 0); + ReadNodoHeader (node, &nh); + nh.level = 0; + nh.free_space = block_size - sizeof (BTreeNodeHeader); + nh.item_count = 0; + WriteNodoHeader (node, &nh); + WriteBlock (node, 0); + delete [] node; } @@ -30,18 +36,105 @@ BTree::~BTree () fclose (fp); } -void BTree::write_tree_header () +void BTree::WriteFileHeader () { fseek (fp, 0L, SEEK_SET); - fwrite (&header, 1, sizeof (BTreeHeader), fp); + fwrite (&header, 1, sizeof (BTreeFileHeader), fp); } -void BTree::write_block (uchar *block, uint num) +void BTree::WriteBlock (uchar *block, uint num) { - fseek (fp, num*header.block_size + sizeof (BTreeHeader), SEEK_SET); + fseek (fp, num*header.block_size + sizeof (BTreeFileHeader), SEEK_SET); fwrite (block, 1, header.block_size, fp); } -void BTree::AddKey () {} -void BTree::DelKey () {} +void BTree::AddKey (const Clave &k) +{ + AddKeyR (&k, 0); +} + +Clave* BTree::AddKeyR (const Clave *k, uint node_num) +{ + Clave *kout; + std::list node_keys; + + /* Leo el nodo raiz para empezar a agregar */ + uchar *node = ReadBlock (node_num); + BTreeNodeHeader node_header; + ReadNodoHeader (node, &node_header); + + node_keys = ReadKeys (node, node_header); + + if (node_header.free_space >= k->Size ()) { + /* TODO : Insertar ordenado */ + //node_keys.push_back (BTreek->Clone ()); + } else { + /* Split */ + } + + + WriteKeys (node, node_header, node_keys); + WriteNodoHeader (node, &node_header); + WriteBlock (node, node_num); + + delete [] node; + + return kout; +} + +void BTree::DelKey (const Clave &k) {} + +void BTree::ReadNodoHeader (uchar *node, BTreeNodeHeader *header) +{ + memcpy (header, node, sizeof (BTreeNodeHeader)); +} + +void BTree::WriteNodoHeader (uchar *node, BTreeNodeHeader *header) +{ + memcpy (node, header, sizeof (BTreeNodeHeader)); +} + +uchar *BTree::ReadBlock (uint num) +{ + uchar *out = new uchar[header.block_size]; + + fseek (fp, num*header.block_size + sizeof (BTreeFileHeader), SEEK_SET); + fread (out, 1, header.block_size, fp); + + return out; +} + +std::list BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_header) +{ + std::list keys; + node += sizeof (BTreeNodeHeader); + + for (uint i=0; i &keys) +{ + std::list::iterator it = keys.begin (); + + node += sizeof (BTreeNodeHeader); + while (it != keys.end ()) { + BTreeData d = (*it); + memcpy (node, d.ToArray(), d.Size ()); + node += d.Size (); + it++; + } + + /* TODO : incrementar node_header.item_count aca o fuera de este metodo? */ +}