"Thinkinginc++" 64, reload new and delete, to mimic the allocation of memory

Tag:thinkinginc++    operator overload    new   delete   

/*** book: "thinkinginc++" * Function: Reload new and delete to mimic memory allocation * Time: October 5, 2014 14:30:11* Author: cutter_point*/#include <cstddef> size_t this type of use # include <fstream> #include <iostream> #include <new>using namespace Std;ofstream out    ("Framis.txt"); class framis{enum {sz=10};    static unsigned char pool[];    This force mimics the memory pool static bool alloc_map[];    This is used to mark the allocated or unallocated memory Public:enum {psize=100};    Framis () {out<< "Framis () \ n";}    ~framis () {out<< "~framis () ...";}    void* operator New (size_t) throw (Bad_alloc); Exception here does not say long, behind will specialize in learning void operator delete (void*);};   unsigned char framis::p ool[psize*sizeof (Framis)];  This sets the memory pool to the number of objects that can be initially stored bool Framis::alloc_map[psize]={false}; Full initialization is not assigned, falsevoid* framis::operator New (size_t) throw (Bad_alloc) {for (int i=0; i<psize; ++i) if (!allo  C_map[i])//until it encounters the first block of unallocated space {alloc_map[i]=true; Mark this space has been used by return pool+ (I*sizeof (Framis)); Return to where it was assigned} out<< "Out of Memory" <&Lt;endl;  Throw Bad_alloc ();    Throws an exception}void Framis::operator delete (void* m) {if (!m) return;   unsigned long block= (unsigned long) m (unsigned long) pool; M minus the starting place indicates the size of the memory block/=sizeof (Framis);    A total of several objects to be recycled out<< "freeing block" <<block<<endl; Alloc_map[block]=false;    Recycle to reset to False}int main () {framis* f[framis::p size];        try {for (int i=0; I<framis::p size; ++i) f[i]=new Framis;    New Framis;    } catch (Bad_alloc) {cerr<< "Out of Memory" <<endl;    } Delete f[10];    f[10]=0;    framis* x=new Framis;   Delete x;    This will be recycled f[10], will not be recycled after 10 for (int j=0; J<framis::p size; ++j) Delete f[j]; return 0;}

"Thinkinginc++" 64, reload new and delete, to mimic the allocation of memory