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#include <string.h>
#include "winhack.h"
#include "drvlib.h"
#include "dpmi.h"
#pragma code_seg( _INIT )
void drv_memcpy(void __far *dst, void __far *src, long size)
{
unsigned char __far *psrc = src;
unsigned char __far *pdst = dst;
while(size-- > 0)
{
*pdst = *psrc;
psrc++;
pdst++;
}
}
void __far *drv_malloc(DWORD dwSize, DWORD __far *lpLinear)
{
WORD wSel;
DWORD dwLin;
wSel = DPMI_AllocLDTDesc(1);
if(!wSel)
return NULL;
dwLin = DPMI_AllocMemBlk(dwSize);
if(dwLin)
{
DPMI_SetSegBase(wSel, dwLin);
DPMI_SetSegLimit(wSel, dwSize - 1);
*lpLinear = dwLin;
return wSel :> 0;
}
return NULL;
}
void drv_free(void __far *ptr, DWORD __far *lpLinear)
{
DWORD sel = ((DWORD)ptr) >> 16;
if(*lpLinear != 0)
{
DPMI_FreeMemBlk(*lpLinear);
*lpLinear = 0;
}
if(sel != 0)
{
DPMI_FreeLDTDesc(sel);
}
}
/**
* MEMSET for area larger than one segment. This function is not very effective,
* I assume it will be called only in few speed non critical situation
* (driver/screen inicialization or reset).
*
* @param dwLinearBase: linear address
* @param dwOffset: offset to linear address
* @param value: value to set (same bahaviour as C memset)
* @param dwNum: number of bytes to set;
*
**/
void drv_memset_large(DWORD dwLinearBase, DWORD dwOffset, UINT value, DWORD dwNum)
{
WORD wSel;
DWORD dwLinPtr;
DWORD dwLinPtrMax;
WORD wAddr;
BYTE __far *lpPM16Ptr;
wSel = DPMI_AllocLDTDesc(1);
if(!wSel) return;
dwLinPtr = dwLinearBase + dwOffset;
dwLinPtrMax = dwLinPtr + dwNum;
/* overflow or nothing to do */
if(dwLinPtrMax <= dwLinPtr) return;
DPMI_SetSegBase(wSel, dwLinPtr);
DPMI_SetSegLimit(wSel, 0xFFFF);
for(; dwLinPtr < dwLinPtrMax; dwLinPtr++)
{
wAddr = dwLinPtr & 0xFFFF;
/* move to new segment */
if(wAddr == 0x0000)
{
DPMI_SetSegBase(wSel, dwLinPtr);
}
lpPM16Ptr = (BYTE __far *)(wSel :> wAddr);
*lpPM16Ptr = value;
}
DPMI_FreeLDTDesc(wSel);
}
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