include/callback.h

/*
 *  Copyright (C) 2002-2020  The DOSBox Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */


#ifndef DOSBOX_CALLBACK_H
#define DOSBOX_CALLBACK_H

#ifndef DOSBOX_MEM_H
#include "mem.h"
#endif 

typedef Bitu (*CallBack_Handler)(void);
extern CallBack_Handler CallBack_Handlers[];

enum { CB_RETN,CB_RETF,CB_RETF8,CB_IRET,CB_IRETD,CB_IRET_STI,CB_IRET_EOI_PIC1,
                CB_IRQ0,CB_IRQ1,CB_IRQ1_BREAK,CB_IRQ9,CB_IRQ12,CB_IRQ12_RET,CB_IRQ6_PCJR,CB_MOUSE,
                /*CB_INT28,*/CB_INT29,CB_INT16,CB_HOOKABLE,CB_TDE_IRET,CB_IPXESR,CB_IPXESR_RET,
                CB_INT21,CB_INT13,CB_VESA_WAIT,CB_VESA_PM,CB_IRET_EOI_PIC2,CB_CPM,
        CB_RETF_STI,CB_RETF_CLI};

/* NTS: Cannot make runtime configurable, because CB_MAX is used to define an array */
#define CB_MAX          128U
#define CB_SIZE         32U

/* we can make THESE configurable though! */
//#define CB_SEG        0xF000
//#define CB_SOFFSET    0x1000
extern Bit16u CB_SEG,CB_SOFFSET;

enum {  
        CBRET_NONE=0,CBRET_STOP=1
};

extern Bit8u lastint;

static INLINE RealPt CALLBACK_RealPointer(Bitu callback) {
        return RealMake(CB_SEG,(Bit16u)(CB_SOFFSET+callback*CB_SIZE));
}
static INLINE PhysPt CALLBACK_PhysPointer(Bitu callback) {
        return PhysMake(CB_SEG,(Bit16u)(CB_SOFFSET+callback*CB_SIZE));
}

static inline PhysPt CALLBACK_GetBase(void) {
        return (PhysPt)(((PhysPt)CB_SEG << (PhysPt)4U) + (PhysPt)CB_SOFFSET);
}

Bit8u CALLBACK_Allocate();

void CALLBACK_Idle(void);


void CALLBACK_RunRealInt(Bit8u intnum);
void CALLBACK_RunRealFar(Bit16u seg,Bit16u off);
void CALLBACK_RunRealFarInt(Bit16u seg,Bit16u off);

bool CALLBACK_Setup(Bitu callback,CallBack_Handler handler,Bitu type,const char* descr);
Bitu CALLBACK_Setup(Bitu callback,CallBack_Handler handler,Bitu type,PhysPt addr,const char* descr);

void CALLBACK_SetDescription(Bitu nr, const char* descr);
const char* CALLBACK_GetDescription(Bitu nr);

void CALLBACK_SCF(bool val);
void CALLBACK_SZF(bool val);
void CALLBACK_SIF(bool val);

extern Bitu call_priv_io;


class CALLBACK_HandlerObject{
private:
        bool installed;
        Bitu m_callback;
        enum {NONE,SETUP,SETUPAT} m_type;
    struct {    
                RealPt old_vector;
                Bit8u interrupt;
                bool installed;
        } vectorhandler;
public:
        CALLBACK_HandlerObject():installed(false),m_callback(0/*NULL*/),m_type(NONE) {
                vectorhandler.installed=false;
        }
        ~CALLBACK_HandlerObject();

        //Install and allocate a callback.
        void Install(CallBack_Handler handler,Bitu type,const char* description);
        void Install(CallBack_Handler handler,Bitu type,PhysPt addr,const char* description);

        void Uninstall();

        //Only allocate a callback number
        void Allocate(CallBack_Handler handler,const char* description=0);
        Bit16u Get_callback() {
                return (Bit16u)m_callback;
        }
        RealPt Get_RealPointer() {
                return CALLBACK_RealPointer(m_callback);
        }
        void Set_RealVec(Bit8u vec,bool reinstall=false);
};
#endif