Lectura de claves desde un nodo a memoria.

La idea es que luego de cargar un bloque feo y molesto de trabajar
se carga una std::list con todas las claves. Para agregar o borrar se lo hace
en la lista y luego se llama a WriteKeys (todavia no se implemento) para volver
a poner las claves en el bloque en modo "binario".

diff --git a/src/btree.cpp b/src/btree.cpp
index a2853927f3221f41c149ba4bd56511d5011c1a8a..d1fbab3b13281de444fd20858aef443b0785935f 100644 (file)
--- a/src/btree.cpp
+++ b/src/btree.cpp
@@ -48,13 +48,18 @@ void BTree::write_block (uchar *block, uint num)
        fwrite (block, 1, header.block_size, fp);
 }
 
        fwrite (block, 1, header.block_size, fp);
 }
 

-void BTree::AddKey (Clave &k)
+void BTree::AddKey (const Clave &k)

 {
 {

+       std::list<Clave *> node_keys;
+

        /* Leo el nodo raiz para empezar a agregar */
        uchar *root = ReadBlock (0);
        BTreeNodeHeader root_header;
        ReadNodoHeader (root, &root_header);
 
        /* Leo el nodo raiz para empezar a agregar */
        uchar *root = ReadBlock (0);
        BTreeNodeHeader root_header;
        ReadNodoHeader (root, &root_header);
 

+       node_keys = ReadKeys (root, root_header);
+       std::cout << node_keys.size () << std::endl;
+       

        if (root_header.free_space >= k.Size ()) {
                std::cout << "Hay lugar para meter la clave" << std::endl;
        } else {
        if (root_header.free_space >= k.Size ()) {
                std::cout << "Hay lugar para meter la clave" << std::endl;
        } else {


@@ -64,7 +69,7 @@ void BTree::AddKey (Clave &k)
        delete [] root;
 }
 
        delete [] root;
 }
 

-void BTree::DelKey (Clave &k) {}
+void BTree::DelKey (const Clave &k) {}

 
 void BTree::ReadNodoHeader (uchar *node, BTreeNodeHeader *header)
 {
 
 void BTree::ReadNodoHeader (uchar *node, BTreeNodeHeader *header)
 {


@@ -86,3 +91,21 @@ uchar *BTree::ReadBlock (uint num)
        return out;
 }
 
        return out;
 }
 

+std::list<Clave *> BTree::ReadKeys (uchar *node, BTreeNodeHeader &node_header)
+{
+       std::list<Clave *> keys;
+       node += sizeof (BTreeNodeHeader);
+
+       for (uint i=0; i<node_header.item_count; i++) {
+               /* TODO : El tipo de clave deberia ser usado 
+                * dependiendo de algun dato en el header del
+                * arbol
+                */
+               ClaveFija *k = new ClaveFija (node);
+               node += k->Size ();
+               keys.push_back (k);
+       }
+
+       return keys;
+}
+

diff --git a/src/btree.h b/src/btree.h
index 081c43687c884a4b69fd00fdc3b5878409cc335b..95180b0386f5290862154edac458549cb0fa8d80 100644 (file)
--- a/src/btree.h
+++ b/src/btree.h
@@ -46,8 +46,10 @@
 
 #include <iostream>
 #include <string>
 
 #include <iostream>
 #include <string>

+#include <list>

 #include "common.h"
 #include "clave.h"
 #include "common.h"
 #include "clave.h"

+#include "clave_fija.h"

 
 /* alias para codear menos :) */
 
 
 /* alias para codear menos :) */
 


@@ -86,8 +88,8 @@ class BTree {
                BTree (const std::string &filename, unsigned int block_size, bool create_new_file = false);
                ~BTree ();
 
                BTree (const std::string &filename, unsigned int block_size, bool create_new_file = false);
                ~BTree ();
 

-               void AddKey (Clave &k);
-               void DelKey (Clave &k);
+               void AddKey (const Clave &k);
+               void DelKey (const Clave &k);

 
        private:
                void write_tree_header ();
 
        private:
                void write_tree_header ();


@@ -98,6 +100,8 @@ class BTree {
                void ReadNodoHeader (uchar *node, BTreeNodeHeader *header);
                void WriteNodoHeader (uchar *node, BTreeNodeHeader *header);
 
                void ReadNodoHeader (uchar *node, BTreeNodeHeader *header);
                void WriteNodoHeader (uchar *node, BTreeNodeHeader *header);
 

+               std::list<Clave *> ReadKeys (uchar *node, BTreeNodeHeader &node_header);
+

                std::string filename;
                BTreeFileHeader header;
 
                std::string filename;
                BTreeFileHeader header;