//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
#include "windows.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void TForm1::info (AnsiString s)
{
   Memo1->Lines->Append (s);
}
//---------------------------------------------------------------------------

struct FileName
{
   int d;
   char name [];
};

struct FileData
{
   unsigned int d;
   char data [];
};

void * uloz (void * u, char * jm, int n, char v)
{
   FileName * fn = (FileName *) u;
   fn->d = strlen (jm);
   // strcpy (fn->name, jm);
   memcpy (fn->name, jm, fn->d);

   FileData * fd = (FileData *)
                   ((char *) u + sizeof (fn->d) + fn->d);
   fd->d = n;
   for (int i = 0; i < n; i ++)
      fd->data [i] = v;

   return (void *) ((char *) fd + sizeof (fd->d) + fd->d);
}

void __fastcall TForm1::Button1Click(TObject *Sender)
{
   HANDLE f;
   f = CreateFile (
       "C:\\work\\abc.dat", // pointer to name of the file
       GENERIC_READ | GENERIC_WRITE, // access (read-write) mode
       0, // share mode
       NULL, // pointer to security attributes
       CREATE_ALWAYS, // how to create
       0,	// file attributes
       NULL 	// handle to file with attributes to copy
       );

    if (f == INVALID_HANDLE_VALUE)
      info ("Nejde otevrit");
    else
    {
      info ("Otevreno");

      HANDLE m;
      m = CreateFileMapping
          (f,// handle to file to map
           NULL, // optional security attributes
           PAGE_READWRITE, // protection for mapping object
           0,	// high-order 32 bits of object size
           16*1024,	// low-order 32 bits of object size
           NULL // name of file-mapping object
           );

      if (m == NULL)
         info ("Nelze zobrazit");
      else
      {
         info ("Zobrazeno (1)");

         void * p;

         p = MapViewOfFile
               (m,// file-mapping object to map into address space
                FILE_MAP_WRITE,	// access mode
                0,	// high-order 32 bits of file offset
                0,	// low-order 32 bits of file offset
                8*1024 	// number of bytes to map
                );

         if (p == NULL)
            info ("Nelze vytvorit pohled");
         else
         {
            info ("Zobrazeno (2)");

            char * c = (char *) p;

            c[0] = 'K';
            c[1] = 'L';
            c[2] = 'M';

            strcpy (c+3, "Hello");

            void * u = p;
            u = uloz (u, "PrvniSoubor.txt", 100, 'a');
            u = uloz (u, "DruhySoubor.txt", 200, 'b');



            UnmapViewOfFile (p);
         }

         CloseHandle (m);
      }
      CloseHandle (f);
    }

}
//---------------------------------------------------------------------------