/*********************************************/
/*** DOS memory allocation - DOSMEM.C      ***/ 
/*** vykostena verze chlumakova memalloc.c ***/
/*********************************************/

#include <dos.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "dosmem.h"


/*** Alokace pole v dolni pameti ***/

void *mem_alloc(int size) 
{
	static union REGS r;
	MEMREC memrec;

   	r.x.eax=0x0100;	      
	r.x.ebx=(size>>4)+1;      
	size=r.x.ebx<<4;      
	int386(0x31,&r,&r);      
	if (r.x.cflag)        
		{
		printf ("No fucking DOS memory left!!!");          
		exit(1);          
		}                
	memrec.ptr=(void *)((r.x.eax&0xFFFF)<<4);      
	Selector=memrec.selector=(short int)r.x.edx;      

	return memrec.ptr;
} 


/*** Uvolneni dolni pameti ***/

void mem_free(void *ptr) 
{
	union REGS r;  

	if(ptr!=NULL)        
		{
		r.x.eax=0x0101;     	     
		r.x.edx=Selector;     	     
		int386(0x31,&r,&r);     	     
		if(r.x.cflag)     	       
			printf("Cannot free DOS memory!!!!");                  
		}

} 


/*** Vyvolani preruseni pomoci protected modu ***/

void WtNs386(int IntNum, DPMIREGS *dpmiregs) 
{
	union REGS r;
	struct SREGS sr;
  
	r.w.ax=0x300;		
	r.h.bl=(char)IntNum;
	r.h.bh=0;
	r.w.cx=0;
	segread(&sr);
	sr.es=FP_SEG(dpmiregs);
	r.x.edi=FP_OFF(dpmiregs);

	int386x(0x31,&r,&r,&sr);
}