Re: cout << char*

Hi,

I have the following program supposed to show C drawbacks:

CLib.h
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typedef struct CStashTag {
  int size; // Size of each space
  int quantity; // Number of storage spaces
  int next; // Next empty space
  // Dynamically allocated array of bytes:
  unsigned char* storage;
} CStash;

void initialize(CStash* s, int size);
void cleanup(CStash* s);
int add(CStash* s, const void* element);
void* fetch(CStash* s, int index);
int count(CStash* s);
void inflate(CStash* s, int increase);
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library.cpp
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#include "CLib.h"
#include <iostream>
#include <cassert>
using namespace std;
// Quantity of elements to add
// when increasing storage:
const int increment = 100;

void initialize(CStash* s, int sz) {
  s->size = sz;
  s->quantity = 0;
  s->storage = 0;
  s->next = 0;
}

int add(CStash* s, const void* element) {
  if(s->next >= s->quantity) //Enough space left?
    inflate(s, increment);
  // Copy element into storage,
  // starting at next empty space:
  int startBytes = s->next * s->size;
  unsigned char* e = (unsigned char*)element;
  for(int i = 0; i < s->size; i++)
    s->storage[startBytes + i] = e[i];
  s->next++;
  return(s->next - 1); // Index number
}

void* fetch(CStash* s, int index) {
  // Check index boundaries:
  assert(0 <= index);
  if(index >= s->next)
    return 0; // To indicate the end
  // Produce pointer to desired element:
  return &(s->storage[index * s->size]);
}

int count(CStash* s) {
  return s->next; // Elements in CStash
}

void inflate(CStash* s, int increase) {
  assert(increase > 0);
  int newQuantity = s->quantity + increase;
  int newBytes = newQuantity * s->size;
  int oldBytes = s->quantity * s->size;
  unsigned char* b = new unsigned char[newBytes];
  for(int i = 0; i < oldBytes; i++)
    b[i] = s->storage[i]; // Copy old to new
  delete [](s->storage); // Old storage
  s->storage = b; // Point to new memory
  s->quantity = newQuantity;
}

void cleanup(CStash* s) {
  if(s->storage != 0) {
   cout << "freeing storage" << endl;
   delete []s->storage;
  }
}
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main.cpp
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#include "CLib.h"
#include <fstream>
#include <iostream>
#include <string>
#include <cassert>
using namespace std;

int main() {
  // Define variables at the beginning
  // of the block, as in C:
  CStash intStash, stringStash;
  int i;
  char* cp;
  ifstream in;
  string line;
  const int bufsize = 80;
  // Now remember to initialize the variables:
  initialize(&intStash, sizeof(int));
  for(i = 0; i < 100; i++)
    add(&intStash, &i);
  for(i = 0; i < count(&intStash); i++)
    cout << "fetch(&intStash, " << i << ") = "
         << *(int*)fetch(&intStash, i)
         << endl;
  // Holds 80-character strings:
  initialize(&stringStash, sizeof(char)*bufsize);
  in.open("main.cpp");
  assert(in);
  while(getline(in, line))
    add(&stringStash, line.c_str());
  i = 0;
  while((cp = (char*)fetch(&stringStash,i++))!=0)
    cout << "fetch(&stringStash, " << i << ") = "
         << cp << endl;
  cleanup(&intStash);
  cleanup(&stringStash);
  system("pause");
}
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I have 2 questions:
1) why do we include CLib.h in library.cpp while it is already included in
main.cpp
2) in order to print he content of intStash we did :
cout << *(int*)fetch(&intStash, i)
I see we are writing cout << (char*)fetch(&stringStash,i++) for the
structure containing arrays of char
Since cout is always able to display the char array ending with '\0' when I
pass to it a char* (cp in this case), how could I ask him to display the
address contained in cp?

Thank you