Error when dumping PE file

sawerr

Hi In my program i want to use BOOL MapAndLoad( PSTR ImageName, PSTR DllPath, PLOADED_IMAGE LoadedImage, BOOL DotDll, BOOL ReadOnly ); function in Imagehlp.h . CPE::CPE(CString fileName, CString filePath):fileName(fileName),filePath(filePath) { LOADED_IMAGE loi; ::MapAndLoad((LPSTR)(LPCTSTR)fileName, (LPSTR)(LPCTSTR)filePath, &loi,FALSE, TRUE); int i = loi.NumberOfSections; char q[50]; sprintf(q,"%d",i); MessageBox(NULL, q,NULL,0); } When i compiled and execute it. It gives error Messagebox with value -858993460 . I changed my projects setting use multibyte character set. wchar_t to char. But can not find solution. What is wrong with this code? How can i fix it? Thanks.

David Crow

sawerr wrote:

What is wrong with this code?

You did not check the return value from MapAndLoad(), nor did you call GetLastError().

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

sawerr

I checked the return value, it is not TRUE MapAndLoad() is not working. I changed code because of pstr parameters. CPE::CPE(CString fileName, CString filePath):fileName(fileName),filePath(filePath) { char *ch1 = strdup(fileName); char *ch2 = strdup(filePath); MessageBox(NULL, ch1, ch2, 0); PLOADED_IMAGE loi = ::ImageLoad((PSTR)ch1, (PSTR)ch2); BOOL b = ::MapAndLoad(ch1, ch2, loi,TRUE, TRUE); if(b == TRUE) { MessageBox(NULL, "DONE", NULL, 0); } ULONG i = loi->NumberOfSections; char q[50]; sprintf(q,"%d",i); MessageBox(NULL, q,NULL,0); } fileName and filePath parameters correct (they are coming from CFileDialog) but it gives run-time error in line ULONG i = loi->NumberOfSections; Unhandled exception at 0x76c977f2 in PEInside.exe: 0xC0000005: Access violation writing location 0x00000004. Do you have any suggestions?

David Crow

If MapAndLoad() is returning 0, why are you then proceeding to dereference loi?

sawerr wrote:

Do you have any suggestions?

Yes.

BOOL b = ::MapAndLoad(ch1, ch2, loi, TRUE, TRUE);
if (b)
{
CString q;

q.Format("%lu", loi->NumberOfSections);
AfxMessageBox(q);

}
else
{
CString q;

q.Format("%lu", GetLastError());
AfxMessageBox(q);

}

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

sawerr

Thanks for your help your last post really help me, i understood how i must write. Thank you. Good works...