中国DOS联盟

小弟做嵌入式系统的开发，使用PC104板，CPU为486，内存16M，操作系统为DOS。现在编了一C程序，里面用到动态分配内存空间函数MALLOC用于存储数据，本打算存储10000个数据点，可是由于内存原因，只能存促4000个数据，同时farmalloc函数无法使用，请问各位大侠如何解决这一问题。

可以進到保護模式嗎

#ifndef XMSMEM_H
#define XMSMEM_H

#include
#include

typedef int BOOL;
#define FALSE 0
#define TRUE 1

//-------- XMS class function prototype ---------
class CXMSManager
{
friend class CXMSBlock;

struct XMSMOVE {
unsigned long length;
unsigned int s_handle;
unsigned long s_offset;
unsigned int d_handle;
unsigned long d_offset;
};

BOOL initialize();
BOOL transfer(XMSMOVE*);
unsigned alloc(unsigned nKB);
void free(unsigned handle);

public:
CXMSManager();
~CXMSManager();

unsigned Version();
unsigned TotalKB();
unsigned FreeKB();
};

extern CXMSManager XMSManager;
//---------------------------------------------------------------------
class CXMSBlock
{
unsigned Handle;
unsigned nKB;

public:
CXMSBlock();
CXMSBlock(unsigned nKB);
~CXMSBlock();

BOOL alloc(unsigned nKB);
void free();
unsigned getKB() { return nKB; }

BOOL input(char far *buf, unsigned long offset, unsigned long len); //len must not be odd?
BOOL output(char far *buf, unsigned long offset, unsigned long len); //len must be even?

BOOL input(CXMSBlock *mem, unsigned long offset1, unsigned long offset, unsigned long len);
BOOL output(CXMSBlock *mem, unsigned long offset1, unsigned long offset, unsigned long len);

BOOL loadFile(const char *fname, unsigned long from, unsigned long length);
};

#endif

#include "XMSMEM.H"

CXMSManager XMSManager;

static void far (*XMSVector)() = NULL;

CXMSManager::CXMSManager()
{
initialize();
}

CXMSManager::~CXMSManager()
{
}

BOOL CXMSManager::initialize()
{
union REGS r;
struct SREGS sr;
r.x.ax = 0x4300;
int86(0x2f,&r,&r);
if(r.h.al != 0x80)
{
XMSVector = NULL;
return FALSE;
}

r.x.ax = 0x4310;
int86x(0x2f,&r,&r,&sr);
XMSVector = (void far (*)())MK_FP(sr.es, r.x.bx);
return TRUE;
}

unsigned CXMSManager::Version()
{
if(XMSVector == NULL) return 0;

asm {
MOV AX,0
CALL XMSVector
}
return _AX;
}

unsigned CXMSManager::TotalKB()
{
if(XMSVector == NULL) return 0;

asm {
MOV AH,8
CALL XMSVector
}
if(_BL>=0X80 && _BL=0X80 && _BLnKB = nKB, TRUE) : (this->nKB = 0 , FALSE);
}

void CXMSBlock::free()
{
XMSManager.free(Handle);
Handle = 0;
nKB = 0;
}

BOOL CXMSBlock::input(char far *buf, unsigned long offset, unsigned long len)
{
struct CXMSManager::XMSMOVE xms = {len, 0, (unsigned long)buf, Handle, offset};
return XMSManager.transfer(&xms);
}

BOOL CXMSBlock:<img src="images/smilies/face-surprise.png" align="absmiddle" border="0">utput(char far *buf, unsigned long offset, unsigned long len)
{
struct CXMSManager::XMSMOVE xms = {len, Handle, offset, 0, (unsigned long)buf};
return XMSManager.transfer(&xms);
}

BOOL CXMSBlock::input(CXMSBlock *mem, unsigned long offset1, unsigned long offset, unsigned long len)
{
struct CXMSManager::XMSMOVE xms = {len, mem->Handle, offset1, Handle, offset};
return XMSManager.transfer(&xms);
}

BOOL CXMSBlock:<img src="images/smilies/face-surprise.png" align="absmiddle" border="0">utput(CXMSBlock *mem, unsigned long offset1, unsigned long offset, unsigned long len)
{
struct CXMSManager::XMSMOVE xms = {len, Handle, offset, mem->Handle, offset1};
return XMSManager.transfer(&xms);
}

BOOL CXMSBlock::loadFile(const char *filename, unsigned long from, unsigned long length)
{
FILE *fp = fopen(filename, "rb"<img src="images/smilies/face-wink.png" align="absmiddle" border="0">;
if(fp == NULL) return FALSE;

fseek(fp, 0L, SEEK_END);
long filelen = ftell(fp);
if(filelen = length || result < 1024) break;
}

fclose(fp);
return TRUE;
}

楼上的，人家要的是基于C的，你怎么给了个C++的啊？

我也想过这个问题,只是我会的是quickbasic.解决的方法是,借助硬盘或虚拟内存,把大量的数组写成数据文件, 写两个子程序,一个读文件,一个写文件,这样就可以实现大数组.

可以通过以下两种方式使用
1、进入保护模式修改段大小属性好退出实模式。可用到4G内存
2、同过加载himem.sys或emm386.exe来使用
这两种方式我都用过，第一种是个技巧第二种是常用方法。如果需要我把源代码给你

能否给我发一份，
我知道用EMS（就是你说的himeme.sys和emm386)可以用到16M,

>1、进入保护模式修改段大小属性好退出实模式。可用到4G内存
能否给我发一份源代码。谢谢！

alhanhome@21cn.com

XMS或EMS都是将扩展内存影射到基本内存的某一特定地址段，
如果你的程序不加修改还是无法使用扩展内存

能否也发给我一份，谢谢
psjboy@tom.com

hhmmdd的 程序通过稍加修改就可以访问 4G 的内存, 里面少了判断扩展功能了
如果检查XMS版本不低于3需要用功能号 8 和 9 的扩展功能号 88H 和 89H

2、同过加载himem.sys或emm386.exe来使用256m内存，
的源代码么？
能否发一个给我？
tiger205@163.net

这个程序只需要 himem.sys, 与 emm386.exe 无关, 可访问所有的内存 (4G)

// --- xms.h

#ifndef _Head_XMS_H_
#define _Head_XMS_H_

#ifndef FarPtr
#define FarPtr(seg,ofs) ((void _seg *)(seg) + (void near *)(ofs))
#define GetSeg(p) ((unsigned)(void _seg *)(void far *)(p))
#define GetOfs(p) ((unsigned)(p))
#endif

class far TXmsMem
{
public:
typedef struct
{
unsigned long Size; //must be EVEN number
int SourHandle; //0: Conventional Memory
unsigned long SourOffset; //Offset/Conv. Mem. Address
int DestHandle; //0: Conventional memory
unsigned long DestOffset; //Offset/Conv. Mem. Address
}XMMStrcut;

int far DriverAvailable(void); //return true if xms driver installed
int far ExtendedVersion(void); //return true if > 64M memory supported

unsigned far GetVersion(void); //return BCD XMS Version
unsigned far GetRevision(void); //return BCD XMS Driver Revision
unsigned long far GetBlockFreeXMS(void); //(kb) ErrCode -> _XMS_Err
unsigned long far GetTotalFreeXMS(void); //(kb) ErrCode -> _XMS_Err

int far AllocXMS(int far *XMSHandle, unsigned long kbyte); //(kb) 0:error, ErrCode -> _XMS_Err
int far FreeXMS(int XMSHandle); //0:error, ErrCode -> _XMS_Err

//Size must be an EVEN number
//return 0 -> Error, ErrCode -> _XMS_Err
int far MemCpy(int hD, unsigned long oD, int hS, unsigned long oS, unsigned long Size);

int far LockXMSBlock(int Handle, long *Addr);
int far UnLockXMSBlock(int Handle);

far TXmsMem();

private:
static void far (*_XMS_Proc)(void);
static unsigned far _XMS_Version;
int far fXMSDriverInstalled(void);
void far fInitXMSProc(void);
};
extern TXmsMem far xms;

#endif


//--- xms.cpp


#include "xms.h"

void far (*TXmsMem::_XMS_Proc)(void) = 0;
unsigned far TXmsMem::_XMS_Version = 0x0000;
TXmsMem far xms;

far TXmsMem::TXmsMem()
{
if(!DriverAvailable())
{
if(fXMSDriverInstalled())
fInitXMSProc();
if(DriverAvailable())
_XMS_Version=GetVersion();
}
}

int far TXmsMem:<img src="images/smilies/face-smile-big.png" align="absmiddle" border="0">riverAvailable(void)
{
return _XMS_Proc!=0;
}

int far TXmsMem::ExtendedVersion(void)
{
return _XMS_Version>=0x0300;
}

int far TXmsMem::fXMSDriverInstalled(void) //called only in XMS.CPP, not a public proc.
{
asm mov ax,0x4300
asm int 0x2f
return _AL==0x80;
}

void far TXmsMem::fInitXMSProc(void)
{
unsigned int Sgmt,Ofst;
asm mov ax,0x4310
asm int 0x2f
asm mov Ofst,bx
asm mov bx,es
asm mov Sgmt,bx
_XMS_Proc=(void far(*)(void)) FarPtr(Sgmt,Ofst);
}

unsigned far TXmsMem::GetVersion(void)
{
asm xor ah,ah
_XMS_Proc();
return _AX;
}

unsigned far TXmsMem::GetRevision(void)
{
asm xor ah,ah
_XMS_Proc();
return _BX;
}

unsigned long far TXmsMem::GetBlockFreeXMS(void) //return Size (kb); if Error, ErrCode -> _XMS_Err
{
if(ExtendedVersion())
{
unsigned FreeHi, FreeLo;
asm mov ah, 0x88
asm xor bl, bl
_XMS_Proc();
asm mov FreeLo, ax //OPSIZ:
asm db 0x66,0xc1,0xe8,0x10 //SHR EAX 10H
asm mov FreeHi, ax
return ((long)FreeHi< _XMS_Err
{
if(ExtendedVersion())
{
unsigned FreeHi, FreeLo;
asm mov ah, 0x88
asm xor bl, bl
_XMS_Proc();
asm mov FreeLo, dx //OPSIZ:
asm db 0x66,0xc1,0xea,0x10 //SHR EDX 10H
asm mov FreeHi, dx
return ((long)FreeHi< Success, 0 -> Error, ErrCode -> _XMS_Err
{
int Handle, AllocErr;
unsigned kbhi = kbyte>>16;
unsigned kblo = kbyte&0x0000ffff;

if(ExtendedVersion())
{
asm mov ah, 0x89
asm mov dx, kbhi //OPSIZ:
asm db 0x66,0xc1,0xe2,0x10 //SHL EDX, 10H
asm mov dx, kblo
_XMS_Proc();
asm mov AllocErr,ax
//asm mov _XMS_Err,bl
asm mov Handle,dx
*XMSHandle=Handle;
return AllocErr;
}
else
{
asm mov ah, 9
asm mov dx, kblo
_XMS_Proc();
asm mov AllocErr,ax
//asm mov _XMS_Err,bl
asm mov Handle,dx
*XMSHandle=Handle;
return AllocErr;
}
}

int far TXmsMem::FreeXMS(int XMSHandle) //return 1 -> Success, 0 -> Error, ErrCode -> _XMS_Err
{
asm mov ah,0x0a
asm mov dx,XMSHandle
_XMS_Proc();
//asm mov _XMS_Err,bl
return _AX;
}

int far TXmsMem::MemCpy(int hD, unsigned long oD, int hS, unsigned long oS, unsigned long Size)
{
//Size must be an EVEN number //return 1 -> Success, 0 -> Error, ErrCode -> _XMS_Err
XMMStrcut XMSS;
int XMSSSgmt, XMSSOfst;
void far (*XMS_Proc)(void)=_XMS_Proc;

XMSS.Size=Size; //must be EVEN number
XMSS.SourHandle=hS;
XMSS.SourOffset=oS;
XMSS.DestHandle=hD;
XMSS.DestOffset=oD;
XMSSSgmt=GetSeg(&XMSS);
XMSSOfst=GetOfs(&XMSS);

asm push ds
asm push es
asm mov si,XMSSSgmt
asm mov ds,si
asm mov si,XMSSOfst
asm mov ah,0x0b
XMS_Proc();
asm pop es
asm pop ds
//asm mov _XMS_Err,bl
return _AX;
}

int far TXmsMem::LockXMSBlock(int Handle, long *Addr)
{
unsigned int HighWord,LowWord,ErrCode;
asm mov ah,0x0c
asm mov dx,Handle
_XMS_Proc();
asm mov ErrCode,ax
asm mov HighWord,dx
asm mov LowWord,bx
//asm mov _XMS_Err,bl
*Addr=((unsigned long)HighWord<<16)+(unsigned long)LowWord;
return ErrCode;
}

int far TXmsMem::UnLockXMSBlock(int Handle)
{
asm mov ah,0x0d
asm mov dx,Handle
_XMS_Proc();
//asm mov _XMS_Err,bl
return _AX;
}


//-- 使用：

int XmsHandle;
if(!xms.AllocXMS(&XmsHandle,260)) //分配内存
{
//错误
}

//复制数据(访问XMS)

char Buf;

//把 Buf 的 Bytes 字节复制到 XmsHandle 的第 XMSOffset 字节开始的内存位置
xms.MemCpy(XmsHandle,XMSOffset, 0,(long)Buf, Bytes);

//把XmsHandle 的 XMSOffset 开始的 Bytes 字节复制到 Buf 地址
xms.MemCpy(0,(long)Buf, XmsHandle,XMSOffset, Bytes);

//复制内存函数的句柄为零，偏移量为常规内存的地址
//复制内存函数的句柄不为零，偏移量为访问这个句柄的扩展内存的开始位置

xms.FreeXMS(XmsHandle); //释放内存, 退出程序的时候必须释放 XMS 内存
//如果程序退出时忘记释放了，只有重新启动才可以释放了

同过加载himem.sys或emm386.exe来使用 谁有c的源代码