/* DPMI.H
*
* DPMI functions for protected mode MIDAS
*
* $Id: dpmi.h,v 1.2 1997/01/16 18:41:59 pekangas Exp $
*
* Copyright 1996,1997 Housemarque Inc.
*
* This file is part of the MIDAS Sound System, and may only be
* used, modified and distributed under the terms of the MIDAS
* Sound System license, LICENSE.TXT. By continuing to use,
* modify or distribute this file you indicate that you have
* read the license and understand and accept it fully.
*/
#ifndef __DPMI_H
#define __DPMI_H
/* new errors:
errDPMIFailure DPMI failure
errInvalidDescriptor invalid segment descriptor
*/
/****************************************************************************\
* struct dpmiRealCallRegs
* -----------------------
* Description: Real mode calling register value structure
\****************************************************************************/
typedef struct
{
ulong rEDI;
ulong rESI;
ulong rEBP;
ulong reserved;
ulong rEBX;
ulong rEDX;
ulong rECX;
ulong rEAX;
ushort flags;
ushort rES;
ushort rDS;
ushort rFS;
ushort rGS;
ushort rIP;
ushort rCS;
ushort rSP; /* if SS and SP are zero, DPMI will */
ushort rSS; /* provide a small (30 words) stack */
} dpmiRealCallRegs;
#ifdef __cplusplus
extern "C" {
#endif
/****************************************************************************\
*
* Function: int dpmiAllocDescriptor(unsigned *descriptor);
*
* Description: Allocate LDT descriptor. Use dpmiFreeDescriptor to deallocate.
*
* Input: unsigned *descriptor pointer to descriptor number
*
* Returns: MIDAS error code. Descriptor number is written to *descriptor.
*
\****************************************************************************/
int CALLING dpmiAllocDescriptor(unsigned *descriptor);
/****************************************************************************\
*
* Function: int dpmiFreeDescriptor(unsigned descriptor);
*
* Description: Deallocates an LDT descriptor.
*
* Input: unsigned descriptor descriptor to deallocate
*
* Returns: MIDAS error code
*
\****************************************************************************/
int CALLING dpmiFreeDescriptor(unsigned descriptor);
/****************************************************************************\
*
* Function: int dpmiSetSegmentBase(unsigned selector, ulong baseAddr);
*
* Description: Changes the 32-bit linear base address of a selector.
*
* Input: unsigned selector selector number
* ulong baseAddr 32-bit linear base address for
* selector
*
* Returns: MIDAS error code.
*
\****************************************************************************/
int CALLING dpmiSetSegmentBase(unsigned selector, ulong baseAddr);
/****************************************************************************\
*
* Function: int dpmiGetSegmentBase(unsigned selector, ulong *baseAddr);
*
* Description: Reads the 32-bit linear base address of a selector.
*
* Input: unsigned selector selector number
* ulong *baseAddr pointer to the 32-bit linear base
* address of the selector
*
* Returns: MIDAS error code. Selector base address is written to
* *baseAddr.
*
\****************************************************************************/
int CALLING dpmiGetSegmentBase(unsigned selector, ulong *baseAddr);
/****************************************************************************\
*
* Function: int dpmiSetSegmentLimit(unsigned selector, ulong limit);
*
* Description: Changes the limit of a segment selector.
*
* Input: unsigned selector selector number
* ulong limit 32-bit segment limit
*
* Returns: MIDAS error code.
*
\****************************************************************************/
int CALLING dpmiSetSegmentLimit(unsigned selector, ulong limit);
/****************************************************************************\
*
* Function: int dpmiSetSegmentAccessRights(unsigned selector,
* unsigned accessRights);
*
* Description: Changes the access rights of a selector
*
* Input: unsigned selector selector
* unsigned accessRights new access rights for the segment
*
* Returns: MIDAS error code.
*
\****************************************************************************/
int CALLING dpmiSetSegmentAccessRights(unsigned selector,
unsigned accessRights);
/****************************************************************************\
*
* Function: int dpmiCreateCodeAlias(unsigned codeSelector,
* unsigned *selector);
*
* Description: Creates a data descriptor that has the same base and limit
* as a code segment descriptor. Use dpmiFreeDescriptor() to
* deallocate data descriptor.
*
* Input: unsigned codeSelector code segment selector
* unsigned *selector pointer to data segment selector
*
* Returns: MIDAS error code. New data selector is written to *selector.
*
\****************************************************************************/
int CALLING dpmiCreateCodeAlias(unsigned codeSelector, unsigned *selector);
/****************************************************************************\
*
* Function: int dpmiAllocDOSMem(unsigned numParagraphs, unsigned *segment,
* unsigned *selector);
*
* Description: Allocates memory from DOS free memory pool, below 1MB. Use
* dpmiFreeDOSMem() to deallocate.
*
* Input: unsigned numParagraphs number of paragraphs to allocate
* unsigned *segment pointer to real mode segment
* unsigned *selector pointer to selector
*
* Returns: MIDAS error code. Real mode segment of allocated block is
* written to *segment. Protected mode selector for block is
* written to *selector.
*
\****************************************************************************/
int CALLING dpmiAllocDOSMem(unsigned numParagraphs, unsigned *segment,
unsigned *selector);
/****************************************************************************\
*
* Function: dpmiFreeDOSMem(unsigned selector);
*
* Description: Deallocates memory allocated with dpmiAllocDOSMem().
*
* Input: unsigned selector selector for allocated block
*
* Returns: MIDAS error code
*
\****************************************************************************/
int CALLING dpmiFreeDOSMem(unsigned selector);
/****************************************************************************\
*
* Function: int dpmiRealModeInt(unsigned intNum,
* dpmiRealCallRegs *registers);
*
* Description: Simulates a real mode interrupt using DPMI service 0x0300.
* *register MUST contain appropriate register values for
* interrupt (CS:IP is ignored).
*
* Input: unsigned intNum interrupt number
* dpmiRealCallRegs *registers DPMI real mode calling struct
*
* Returns: MIDAS error code. Register values returned by the interrupt
* are written to *registers.
*
\****************************************************************************/
int CALLING dpmiRealModeInt(unsigned intNum, dpmiRealCallRegs *registers);
/****************************************************************************\
*
* Function: int dpmiLockMemory(ulong start, ulong numBytes);
*
* Description: Locks a region of memory to prevent it from being paged. The
* memory can be unlocked using dpmiUnlockMemory().
*
* Input: ulong start memory region start address
* ulong numBytes memory region length in bytes
*
* Returns: MIDAS error code
*
\****************************************************************************/
int CALLING dpmiLockMemory(ulong start, ulong numBytes);
/****************************************************************************\
*
* Function: int dpmiUnlockMemory(ulong start, ulong numBytes);
*
* Description: Unlocks a region of memory locked with dmpiLockMemory().
*
* Input: ulong start memory region start address
* ulong numBytes memory region length in bytes
*
* Returns: MIDAS error code
*
\****************************************************************************/
int CALLING dpmiUnlockMemory(ulong start, ulong numBytes);
#ifdef __cplusplus
}
#endif
#endif
/*
* $Log: dpmi.h,v $
* Revision 1.2 1997/01/16 18:41:59 pekangas
* Changed copyright messages to Housemarque
*
* Revision 1.1 1996/05/22 20:49:33 pekangas
* Initial revision
*
*/
