Question

我收到Access违规读取位置0xCDCDCDD1错误。我正在使用vc9编译器。

我的代码：

#define SRD_EXPORTS
#include "SRD.h"
#include "ISRDPresenter.h"
#include "ISRDFactory.h"
#include "ISRDevice.h"

#include "AString.h"

int main( int argc, char** argv )
{
    ISRDPresenter* dev = (ISRDPresenter*)malloc(sizeof(ISRDPresenter));     // = NewSRDPresenter();

    char act[ 128 ];
    int commands = argc-1;

do
{
    if( !commands )
    {
        act[ 0 ] = 0;
        printf("SRD> ");
#if defined(__IBMC__) || defined (__IBMCPP__)
        fflush(stdout);
#endif
        fgets( act, 128, stdin );
    }
    else
    {
        strncpy( act, argv[ argc - commands-- ], 128 );
        printf("SRD> %s\n", act);
    }

    if( !strncmp( act, "help", 4 ) )
    {
        dev->showHelp( act );
    }
...
}

错误在行dev-＆gt; showHelp（act）; 问题应该在

行

ISRDPresenter* dev = (ISRDPresenter*)malloc(sizeof(ISRDPresenter));

但我无法修复它。如果我改用：

ISRDPresenter* dev = NewSRDPresenter();

它说标识符无法找到，如果我使用：

ISRDPresenter* dev = new ISRDPresenter();

说ISRDPresenter无法实例化抽象类......

ISRDPresenter.h：

#ifndef __ISRDPRESENTER_H
#define __ISRDPRESENTER_H

#define SRD_EXPORTS
#include "SRD.h"
#include "ISRDDataTypes.h"

#include "AIPClass.h"
class ISRDFactory;

class ISRDPresenter
{    
public:
// -----------------------------------------------------------------------
//  Destructor
// -----------------------------------------------------------------------
virtual ~ISRDPresenter() {};

// -----------------------------------------------------------------------
//  Function prototypes
// -----------------------------------------------------------------------  
virtual void showHelp( char* attr ) const = 0;
virtual void showList( void ) const = 0;
virtual void showInfo( size_t i ) const = 0;
virtual void showFirmware( size_t i ) const = 0; 
};

#endif /* __ISRDPRESENTER_H */

SRDPresenter.h：

#ifndef __SRDPRESENTER_H
#define __SRDPRESENTER_H

#define SRD_EXPORTS
#include "SRD.h"
#include "ISRDPresenter.h"

#include "AString.h"
#include "ISRDFactory.h"

//-----------------------------------------------------------------------------
// ASRDPresenter
//-----------------------------------------------------------------------------
class ASRDPresenter : public ISRDPresenter
{
public:
//-------------------------------------------------------------------------
// ASRDPresenter constructor & destructor
//-------------------------------------------------------------------------
ASRDPresenter();
virtual ~ASRDPresenter(){};

//-------------------------------------------------------------------------
// Function prototypes
//-------------------------------------------------------------------------
void showHelp( char* attr  ) const;
void showList( void ) const;
void showInfo( size_t i ) const;
void showFirmware( size_t i ) const;

private:
    ISRDFactory* f_srds;

};

SRD_EXPORT_PREF ISRDPresenter* SRD_EXPORT_POST NewSRDPresenter()
{
    return new ASRDPresenter();
}


#endif /* __SRDPRESENTER_H */

SRDPresenter.cpp：

#define SRD_EXPORTS
#include "SRDPresenter.h"

#if defined(_MSC_VER)
    #define WIN32_LEAN_AND_MEAN
#endif

// ---------------------------------------------------------------------------
//  ASRDPresenter
// ---------------------------------------------------------------------------

ASRDPresenter::ASRDPresenter()
:f_srds( )
{
    // empty
}

void ASRDPresenter::showHelp( char* attr ) const
{

    if( !strcmp( attr, "help" ) )
    {
        printf( "\nHelp to the ANOVIS SRD command.\n\n" );
        printf( " help                : Print this help.\n" );
        printf( " list                : List all ANOVIS SRD found.\n" );
        printf( " info        
    }    
...
}

我该如何解决？光！ Thanx提前！

Answer 1

使用malloc代替new，您已跳过对象的初始化。模式cdcdcdcd在调试模式构建中写入新分配的内存，以帮助您检测此类问题。您正在尝试访问虚拟功能，该功能正在访问尚未初始化的vtable。

你应该能够：

ISRDPresenter* dev = new ASRDPresenter;

new_srdProg_d.exe中0x0040224d处的未处理异常：0xC0000005：访问冲突读取位置0xcdcdcdd1

1 个答案: