Resource for Source: C/C++/Resource for Source - C-C++.iso/misc_src/cslib16b/include/csvbase.h

C/C++ Source or Header | 1995-11-01 | 5.5 KB | 184 lines

/***********************************************************************

                                      CSDB Library, Version 1.6.b
                                         Released: March 2nd 1995

       Header file of the VBASE class.
       Database class for records with variable length.

                                           Copyright(c) 1994,1995
                                                           Combis
                                                  The Netherlands
***********************************************************************/

#ifndef __CSVBASE_H
#define __CSVBASE_H

#include "cstypes.h"
#include "cspage.h"
#include "cstaba.h"


typedef U32 VBPO;
typedef U32 PANR;
typedef U16 OFNR;

class VBASE: public PAGE
{

 private:


   typedef struct
   {
     VBPO pos;
   } vbi;          //VBase Index

   typedef struct
   {
     unsigned length: 15;
     unsigned delet:   1;
     U16 alloc;
   } dhd;          //Data HeaDer

   typedef struct
   {
     VBPO   pos;
     S16    alloc;
   } edc;          //Empty Data Chain


protected:

   TABLEa vpi;         // Virtual Page Index.
   ARRAY  vpi_cut;     // Virtual Page Index short CUT.

   U16      ipp;         // Indexes Per Page.
   U16      ipp_offmask;
   U16      ipp_shftrig;
   U16      nip;         // Number of pages currently used by the index.

   U16      pag_s;     // Page Shift.
   U16      pag_o;     // Page OR.

   edc     *eda;         // Empty Data Array
   U16      esr;         // Eda Shift Right
   U16      enr;         // Eda NumbeR
   int      epc;         // Eda Page Changed.

   U32      numrec;     // Number of records.
   U16      maxrlen;     // Max Record Length.

   int      rel_shrink;     // Relocate record when shrunk.

   void   init_vpi(void);
   void   init_eca(void);
   void   init_vars(void);
   void   init_defaults(void);
   void   save_vpi(void);
   void   close_vpi(void);
   void   save_eca(void);
   void   close_eca(void);
   void   reset_vpi(void);
   void   reset_eca(void);

   U32      pag(VBPO &p)            { return p>>pag_s;        }
   U16      off(VBPO &p)            { return p&pag_o;        }
   VBPO   vbpo(PANR &p,OFNR &of)    { return (p<<pag_s)|of; }

   CSCHAR   *pos_poa(PANR p,OFNR of)  { return load_page(p)+of;    }
   CSCHAR   *pos_poda(PANR p,OFNR of) { return load_page_d(p)+of; }
   CSCHAR   *pos_poa(VBPO  p)        { return pos_poa(pag(p),off(p));  }
   CSCHAR   *pos_poz(VBPO  p)        { return pos_poa(p)+sizeof(dhd);  }
   CSCHAR   *pos_poda(VBPO  p)        { return pos_poda(pag(p),off(p)); }
   CSCHAR   *pos_podz(VBPO  p)        { return pos_poda(p)+sizeof(dhd); }


   dhd     *DH(void *p) { return (dhd *)p; }

   VBPO   p2i(U32 rec);
   void   p2i(U32 rec,VBPO pos);

   int      is_index_page(PANR p);

   U16      data_alloc(U16 amount,PANR &page,OFNR &offset,void *&ptr);
   void   data_free(void *ptr,PANR page,OFNR  offset,U16 amount);
   U16      data_alloc_full(U16 amount,PANR &page,OFNR &offset,void *&ptr);

   void   sort_eca(void);
   void   set_num_page(PANR n);
   int      max_buf_locked(void )     { return 4; }
   void   numvrec(U32 l)        { numrec=l; }

   void   head2vars(void);
   void   vars2head(void);

   virtual void check_id(U32 id);
   virtual void set_id(void);

////////////////////////////////////////////////////////////////////////
////////////////////// PUBLIC FUNCTIONS////////////////////////////////
////////////////////////////////////////////////////////////////////////
 public:

   VBASE(void);
   ~VBASE(void);


//////////////////////// Definition//////////////////////////////////////////
   int    define(CSCHAR *name,U16 struclen);
   void relocate_when_shrunk(int TrueOrFalse);

//////////////////////// Open & Close////////////////////////////////////////
   int    open(CSCHAR *name,U16 kb_buf);
   int    close(void);
   int    save(void);

//////////////////////// Locate, Read & Writes records///////////////////////
   void read_rec(U32 pos,void *ptr,U16    &length);
   void read_rec(U32 pos,U16  maxlen,void *ptr,U16  &length);
   void write_rec(U32 i,void *d,U16 len);
   CSCHAR *locate(U32 k)         { return pos_podz(p2i(k)); }

//////////////////////// Add Records/////////////////////////////////////////
   U32    append_rec(void *p,U16 len);

//////////////////////// Number of Records///////////////////////////////////
   U32    numvrec(void)         { return numrec; }

//////////////////////// Data in Header Page/////////////////////////////////
/* Inherited
   int    data_2_header(void * ptr,U16 length);
   int    header_2_data(void * ptr,U16 length);
   U16    max_data_in_header(void);
*/

////////////////////////// Deleting////////////////////////////////////////////
   int    is_delet(U32 k)      { return !DH(pos_poa(p2i(k)))->delet; }
   void delet(U32 k)         { DH(pos_poda(p2i(k)))->delet=0;    }
   void undelet(U32 k )      { DH(pos_poda(p2i(k)))->delet=1;    }

////////////////////////// Record Length///////////////////////////////////////
   U16    rec_len(U32 k)         { return DH(pos_poa(p2i(k)))->length; }
   U16    max_len(void)         { return maxrlen; }

//////////////////////// Report Writing//////////////////////////////////////
   U16    report(CSCHAR *name,S16 sub=1);
   void report(FILE *fipo,S16 sub);

////////////////////////// Miscellaneous///////////////////////////////////////
/* Inherited
   int    background(void)
*/
   int    pack(void);
   int    zap(void);
   void empty(void);
   void info(void);
   int    relocate_when_shrunk(void) { return rel_shrink; }
   virtual int class_ID(void)  { return CS_CLID_VBASE; }


};

#endif